WO2014061086A1 - Internal combustion engine equipped with blow-by gas recirculation device - Google Patents

Internal combustion engine equipped with blow-by gas recirculation device Download PDF

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Publication number
WO2014061086A1
WO2014061086A1 PCT/JP2012/076632 JP2012076632W WO2014061086A1 WO 2014061086 A1 WO2014061086 A1 WO 2014061086A1 JP 2012076632 W JP2012076632 W JP 2012076632W WO 2014061086 A1 WO2014061086 A1 WO 2014061086A1
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WO
WIPO (PCT)
Prior art keywords
cylinder
wall
internal combustion
combustion engine
end portion
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Application number
PCT/JP2012/076632
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French (fr)
Japanese (ja)
Inventor
松本　功
Original Assignee
トヨタ自動車株式会社
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Priority to PCT/JP2012/076632 priority Critical patent/WO2014061086A1/en
Publication of WO2014061086A1 publication Critical patent/WO2014061086A1/en

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
    • F02F1/00—Cylinders; Cylinder heads 
    • F02F1/18—Other cylinders

Definitions

  • the present invention relates to a piston reciprocating internal combustion engine including a blow-by gas recirculation device that recirculates (inflows) blow-by gas in a crankcase into an intake passage.
  • blow-by gas contains fine particles (particulate matter, PM) such as soot.
  • the diameter of the particulate matter is, for example, about 0.1 ⁇ m.
  • oil mist liquid fine particles of lubricating oil
  • the diameter of the oil mist is, for example, about 5 ⁇ m and is larger than the diameter of the particulate matter.
  • This oil mist OM is recirculated from the crankcase to the intake passage by a blow-by gas recirculation device. At this time, since the oil mist OM receives heat, the easily evaporated component in the oil mist OM evaporates. Therefore, as shown in FIG. 13B, the diameter of the oil mist OM is reduced, and the density of the particulate matter PM in the oil mist OM is increased. Therefore, the oil mist OM including the particulate matter PM is likely to adhere to other members.
  • the reduced “oil mist containing particulate matter PM” is a member constituting the intake passage (hereinafter referred to as “intake passage constituting member”).
  • intake passage constituting member a member constituting the intake passage
  • a deposit is generated in the intake passage constituting member.
  • Such a deposit is not preferable due to the characteristics of the engine.
  • the oil mist OM rapidly increases in temperature in the compressor and decreases in diameter, so that the density of the particulate matter PM in the oil mist OM greatly increases.
  • a large amount of particulate matter may adhere to the diffuser of the turbocharger and the efficiency of the turbocharger may be significantly reduced.
  • the present invention has been made to address the above-described problems. That is, one of the objects of the present invention is a piston reciprocating motion capable of reducing the amount of deposit generated (attached) to the intake passage constituting member by reducing the amount of oil mist generated in the crankcase.
  • An internal combustion engine is provided.
  • An internal combustion engine is an engine in which a piston provided with an oil ring reciprocates in a cylinder, and a cylinder inner wall portion constituting an inner wall of the cylinder and a blow-by gas in a crankcase that houses a crankshaft are A blow-by gas recirculation device for recirculating to the intake passage of the engine.
  • the cylinder inner wall portion is a cylinder liner when the internal combustion engine is provided with a cylinder liner, and indicates a portion that forms a cylinder bore of the engine body when the internal combustion engine is not provided with a cylinder liner.
  • the cylinder inner wall portion has a special structure for reducing the amount of oil mist generated. That is, the cylinder inner wall portion removes lubricating oil scraped off from the inner wall of the cylinder toward the crankcase by the oil ring, “the portion of the inner wall of the cylinder on the crankcase side (the inner wall of the cylinder "The end opposite to the cylinder head side, that is, the lower end of the inner wall of the cylinder)", and "when the cylinder inner wall is viewed along the axis of the cylinder (that is, the upper surface of the cylinder inner wall). (When viewed) it has a structure in which it is concentrated toward at least one of “a first end and a second end” which is a “pair of portions overlapping with the axis of the crankshaft”.
  • the lubricating oil scraped off from the inner wall of the cylinder toward the crankcase by the oil ring is collected toward at least one of the “first end portion and the second end portion”.
  • the first end portion and the second end portion are both continuous to a “crankshaft journal mounting portion (bearing portion)”. Therefore, the lubricating oil scraped off toward the crankcase flows along the wall surface of the mounting portion of the crankshaft journal from the first end or the second end, and then falls into the oil pan. Therefore, the lubricant that is scraped off toward the crankcase “collises and scatters while falling” on members (crank arms, crankpins, balance weights and / or connecting rods, etc.) that rotate and move at high speed. There is nothing. As a result, since the amount of oil mist (oil splash) generated in the crankcase can be reduced, the amount of deposit attached to the intake passage constituting member can be reduced.
  • the fact that the lubricating oil scraped off by the oil ring concentrates toward the “specific end” means that most of the lubricating oil scraped off by the oil ring collects at the specific end.
  • the fact that the lubricating oil scraped off by the oil ring concentrates toward the “specific end” means that the portion of the lubricating oil scraped off by the oil ring from the portion other than the “predetermined region including the specific end” This means that the amount of lubricant that falls to the side is very small compared to the amount of lubricant that falls to the crankcase side from the ⁇ predetermined region including the specific end portion '' of the lubricant that is scraped off by the oil ring, Therefore, it does not mean that there is no lubricating oil falling from the portion other than the “predetermined region including the specific end portion” to the crankcase side.
  • the cylinder inner wall portion has a structure that concentrates the scraped lubricating oil toward each of the first end portion and the second end portion (that is, both the first end portion and the second end portion). Can have.
  • the cylinder inner wall portion has an end portion on the crankshaft side of the inner wall of the cylinder (a lower end portion of the inner wall of the cylinder) that directs the lubricant to be scraped off to each of the first end portion and the second end portion.
  • an end portion on the crankshaft side of the inner wall of the cylinder a lower end portion of the inner wall of the cylinder that directs the lubricant to be scraped off to each of the first end portion and the second end portion.
  • the oil mist generated in the crankcase is simply changed by changing the shape of the lower end portion of the inner wall of the cylinder (for example, the lower end portion of the cylinder liner or the lower end portion of the engine main body constituting the cylinder). The amount can be reduced.
  • the cylinder inner wall can be configured as described below.
  • the first end portion is separated from a reference virtual plane which is a plane including the axis of the crankshaft and is orthogonal to the axis of the cylinder by a first distance.
  • the second end portion is separated from the reference virtual plane by a second distance;
  • a thrust direction portion which is a portion of the inner wall of the cylinder on the crankcase side and is located in the thrust direction of the piston, is separated from the reference virtual plane by a third distance.
  • An anti-thrust direction portion that is a portion of the inner wall of the cylinder on the crankcase side and is located in the anti-thrust direction of the piston is separated from the reference virtual plane by a fourth distance.
  • the first distance is shorter than any of the third distance and the fourth distance.
  • the second distance is shorter than any of the third distance and the fourth distance.
  • the end on the crankcase side of the inner wall of the cylinder between the first end and the thrust direction portion gradually approaches the reference virtual plane as it approaches the first end from the thrust direction portion.
  • the end on the crankcase side of the inner wall of the cylinder between the second end and the thrust direction portion gradually approaches the reference virtual plane as it approaches the second end from the thrust direction portion.
  • the end on the crankcase side of the inner wall of the cylinder between the first end and the anti-thrust direction portion gradually approaches the reference virtual plane as it approaches the first end from the anti-thrust direction portion. It has a shape that approaches.
  • the end on the crankcase side of the inner wall of the cylinder between the second end and the anti-thrust direction portion gradually approaches the reference virtual plane as it approaches the second end from the anti-thrust direction portion. It has a shape that approaches.
  • the cylinder inner wall portion is configured to have a structure described below.
  • the end of the inner wall of the cylinder on the crankcase side is parallel to a reference virtual plane that is a plane that includes the axis of the crankshaft and is orthogonal to the axis of the cylinder.
  • the end of the inner wall of the cylinder on the crankcase side is located in a portion excluding both the “first region including the first end” and the “second region including the second end”.
  • a flange portion extending in the axial direction of the cylinder from the inner wall of the cylinder.
  • the lubricating oil scraped off from the inner wall of the cylinder toward the crankcase by the oil ring reaches the flange portion provided at the lower end portion of the inner wall of the cylinder, and is changed along the flange portion. It moves toward the first and second ends, and then moves along the “mounting portion of the crankshaft journal” from the vicinity of the first and second ends to the crankcase side. Therefore, the amount of oil mist (oil splash) generated in the crankcase can be reduced.
  • the cylinder inner wall portion may be “from the inner wall of the cylinder toward the inside of the cylinder.
  • a projecting convex portion that extends continuously along the inner wall of the cylinder so as to concentrate the scraped lubricating oil toward the first end and the second end, respectively. It is comprised so that the convex-shaped part which carries out may be provided.
  • the cylinder inner wall portion is a “concave portion provided on the cylinder inner wall”. And “the concave portion extending continuously along the inner wall of the cylinder so that the lubricant to be scraped off is concentrated toward each of the first end portion and the second end portion”. Configured.
  • Lubricating oil scraped off from the inner wall of the cylinder toward the crankcase by the oil ring moves toward the first and second ends along these convex portions or concave portions, and then the first And it moves along the “mounting portion of the crankshaft journal” from the vicinity of the second end portion toward the crankcase side. Therefore, the amount of oil mist (oil splash) generated in the crankcase can be reduced.
  • the cylinder inner wall portion may have a structure that concentrates the lubricating oil scraped off toward only the first end portion of the first end portion and the second end portion.
  • the inner wall portion of the cylinder has an end portion on the crankshaft side of the inner wall of the cylinder (a lower end portion of the inner wall of the cylinder) that says “the lubricating oil to be scraped off and the first end portion and the It is comprised so that it may have a shape which concentrates toward only the said 1st edge part among 2nd edges.
  • the oil mist generated in the crankcase is simply changed by changing the shape of the lower end portion of the inner wall of the cylinder (for example, the lower end portion of the cylinder liner or the lower end portion of the engine main body constituting the cylinder). The amount can be reduced.
  • the cylinder inner wall can be configured as described below.
  • the first end portion is separated by a fifth distance from a reference virtual plane that is a plane that includes the axis of the crankshaft and is orthogonal to the axis of the cylinder.
  • the second end portion is separated from the reference virtual plane by “sixth distance longer than the fifth distance”.
  • the end portion on the crankcase side of the inner wall of the cylinder has a shape that gradually approaches the reference imaginary plane as it approaches the first end portion from the second end portion.
  • the inner wall portion of the cylinder has a structure described below. Configured as follows.
  • the end of the inner wall of the cylinder on the crankcase side is parallel to a reference virtual plane that is a plane that includes the axis of the crankshaft and is orthogonal to the axis of the cylinder.
  • the end portion on the crankcase side of the inner wall of the cylinder includes a flange portion extending from the inner wall of the cylinder in the axial direction of the cylinder in a portion excluding the first region including the first end portion.
  • the lubricating oil scraped off from the inner wall of the cylinder toward the crankcase by the oil ring reaches the flange portion provided at the lower end portion of the inner wall of the cylinder, and is changed along the flange portion. It moves toward one end, and then moves along the “crankshaft journal mounting portion” from the vicinity of the first end toward the crankcase. Therefore, the amount of oil mist (oil splash) generated in the crankcase can be reduced.
  • the inner wall portion of the cylinder is “the inner wall of the cylinder” A convex portion projecting toward the inside of the cylinder ”, and“ the scraped lubricating oil is concentrated toward only the first end portion of the first end portion and the second end portion ”.
  • the inner wall portion of the cylinder is “the inner wall of the cylinder” A convex portion projecting toward the inside of the cylinder ”, and“ the scraped lubricating oil is concentrated toward only the first end portion of the first end portion and the second end portion ”.
  • the cylinder inner wall portion may be “the cylinder inner wall portion”.
  • a concave portion provided on the inner wall of the cylinder so that the lubricant to be scraped is concentrated toward only the first end portion of the first end portion and the second end portion.
  • These internal combustion engines can include a turbocharger including a compressor provided in the intake passage and a turbine provided in the exhaust passage of the engine.
  • the blow-by gas recirculation device may be configured to flow the blow-by gas in the crankcase into the intake passage of the engine and upstream of the compressor.
  • FIG. 1 is a schematic view of an internal combustion engine according to a first embodiment of the present invention.
  • FIG. 2 is a cross-sectional view of the internal combustion engine shown in FIG. 3A and 3B are views showing the cylinder liner shown in FIG. 1, wherein FIG. 3A is a perspective view of the cylinder liner as viewed obliquely from below, and FIG. 3B is a side view of the cylinder liner as viewed along the anti-thrust direction.
  • C is a side view of the cylinder liner as viewed along the axial direction of the crankshaft.
  • D is the cylinder as viewed from the cylinder liner (cylinder) along the axis (center axis). It is a top view (top view) of a liner.
  • FIG. 4 is a perspective view of a cut model of an internal combustion engine according to a modification of the first embodiment of the present invention.
  • FIG. 5 is a view showing a cylinder liner included in an internal combustion engine according to a second embodiment of the present invention.
  • FIG. 5A is a view of the cylinder liner cut by “a plane passing through the axis of the cylinder liner and the axis of the crankshaft”.
  • FIG. 5C is a cross-sectional view (cross-section 1-1 of FIG. 5C)
  • FIG. 5B is a cross-sectional view of the cylinder liner cut along a “plane passing through the axis and thrust direction of the cylinder liner” (FIG. 5C).
  • FIG. 5A is a view of the cylinder liner cut by “a plane passing through the axis of the cylinder liner and the axis of the crankshaft”.
  • FIG. 5C is a cross-sectional view (cross-section 1-1 of FIG. 5C
  • FIG. 2C is a plan view (top view) of the cylinder liner when the cylinder liner is viewed along the axis (center axis) of the cylinder liner (cylinder).
  • FIG. 6A is a cross-sectional view (end view) of the cylinder liner included in the internal combustion engine of the second embodiment of the present invention cut along a “plane passing through the axis and thrust direction of the cylinder liner”.
  • (B) is a cross-sectional view (end view) of a cylinder liner included in an internal combustion engine according to a modification of the second embodiment, cut along a “plane passing through the axis and thrust direction of the cylinder liner”.
  • FIG. 6A is a cross-sectional view (end view) of the cylinder liner included in the internal combustion engine of the second embodiment of the present invention cut along a “plane passing through the axis and thrust direction of the cylinder liner”.
  • (B) is a cross-sectional view (end view) of a
  • FIG. 7 is a cross-sectional view (end view) of the cylinder liner included in the internal combustion engine according to the third embodiment of the present invention cut along a “plane passing through the axis and thrust direction of the cylinder liner”.
  • 8A and 8B are views showing a cylinder liner included in an internal combustion engine according to a fourth embodiment of the present invention.
  • FIG. 8A is a perspective view of the cylinder liner as viewed obliquely from below
  • FIG. 8B is a view showing the cylinder liner.
  • FIG. 8C is a plan view (top view) of the cylinder liner as viewed along the axis (center axis) of the cylinder liner (cylinder), and FIG.
  • FIG. 8C is a plan view of the cylinder liner along line 3-3 in FIG. 8B.
  • FIG. 6D is a cross-sectional view of the cylinder liner cut along a plane along line 4-4 in FIG. 8B.
  • 9A and 9B are views showing a cylinder liner included in an internal combustion engine according to a fifth embodiment of the present invention.
  • FIG. 9A is a perspective view of the cylinder liner as viewed obliquely from below
  • (C) is a side view of the cylinder liner as viewed along the axial direction of the crankshaft
  • (D) is an axis (center axis) of the cylinder liner (cylinder).
  • FIG. 9A is a perspective view of the cylinder liner as viewed obliquely from below
  • (C) is a side view of the cylinder liner as viewed along the axial direction of the crank
  • FIG. 4 is a plan view (top view) of the cylinder liner as viewed along the line ().
  • FIG. 10 is a view showing a cylinder liner included in an internal combustion engine according to a sixth embodiment of the present invention.
  • FIG. 10A shows the cylinder liner as viewed along the axis (center axis) of the cylinder liner (cylinder).
  • a plan view (top view) and (B) of the cylinder liner are cross-sectional views of the cylinder liner cut along a plane along line 7-7 in FIG. 10 (A).
  • FIG. 11 is a cross-sectional view of a cylinder liner included in an internal combustion engine according to a seventh embodiment of the present invention cut along a “plane passing through the axis and thrust direction of the cylinder liner”.
  • FIG. 12A and 12B are views showing a cylinder liner included in an internal combustion engine according to an eighth embodiment of the present invention.
  • FIG. 12A is a perspective view of the cylinder liner as viewed obliquely from below
  • (C) is a plan view of the cylinder liner along line 8-8 in FIG. 12 (B).
  • (D) is a cross-sectional view of the cylinder liner cut along a plane along line 9-9 in FIG. 12 (B).
  • FIG. 13 is a conceptual diagram showing how oil mist and particulate matter change.
  • an internal combustion engine including a blow-by gas recirculation device according to each embodiment of the present invention will be described with reference to the drawings.
  • the internal combustion engine of each embodiment is a piston reciprocating type, in-line, multi-cylinder (4-cylinder), and diesel engine.
  • the present invention can be applied to other types of engines as long as they are piston reciprocating internal combustion engines.
  • the internal combustion engine 10 includes an engine body portion 20, an intake passage portion 30, an exhaust passage portion 40, and a blow-by gas recirculation device 50.
  • the engine body 20 includes a crankcase 21, an oil pan 22, a cylinder block 23, and a cylinder head 24.
  • crankcase 21 rotatably supports the crankshaft 21a.
  • the oil pan 22 is fixed to the crankcase 21 below the crankcase 21.
  • the oil pan 22, together with the crankcase 21, forms a space for accommodating the crankshaft 21 a and the lubricating oil OL (hereinafter also referred to as “crankcase chamber”).
  • the cylinder block 23 is fixed to the crankcase 21 above the crankcase 21.
  • the cylinder block 23 is made of aluminum and includes a plurality of hollow cylinders (cylinder bores) 23a (for four cylinders).
  • a cast iron cylinder liner 23b is fitted into the inner periphery of the cylinder 23a. Therefore, the cylinder liner 23b is “a cylinder inner wall portion constituting the inner wall of the cylinder 23a”.
  • a piston 23c is accommodated in the cylinder 23a.
  • the piston 23c is substantially cylindrical and includes a plurality of piston rings on the side surface.
  • the lowermost ring (crankcase 21 side) of the plurality of piston rings is a so-called “oil ring OR”.
  • the oil ring OR scrapes the lubricating oil (oil film) on the inner wall of the cylinder 23a toward the crankcase 21 while sliding on the inner wall of the cylinder 23a (that is, the inner peripheral wall of the cylinder liner 23b).
  • the piston 23c is connected to the crankshaft 21a by a connecting rod 23d.
  • the upper surface (top surface) of the piston 23 c forms a combustion chamber CC together with the inner wall surface of the cylinder liner 23 b and the lower surface of the cylinder head portion 24.
  • the cylinder head portion 24 is fixed to the cylinder block 23 above the cylinder block 23.
  • the cylinder head portion 24 is formed with an intake port communicating with the combustion chamber CC and an exhaust port communicating with the combustion chamber CC.
  • the intake port is opened and closed by an intake valve.
  • the intake valve is driven by “a cam of an intake cam shaft (not shown)” accommodated in the cylinder head portion 24.
  • the exhaust port is opened and closed by an exhaust valve.
  • the exhaust valve is driven by “a cam of an exhaust cam shaft (not shown)” accommodated in the cylinder head portion 24.
  • the cylinder head portion 24 is covered with a cylinder head cover 24a. Further, a fuel injection valve (not shown) is provided in the cylinder head portion 24.
  • the intake passage 30 includes an intake pipe 31, an intercooler 32, and a compressor 61 of a turbocharger 60.
  • the intake pipe 31 is connected to the intake port. Therefore, the intake pipe 31 and the intake port constitute an intake passage.
  • the compressor 61 is interposed in the intake pipe 31 and compresses intake air.
  • the intercooler 32 is interposed in the intake pipe 31 at a position downstream of the compressor 61, and cools intake air.
  • the exhaust passage section 40 includes an exhaust pipe 41 and a turbine 62 of the turbocharger 60.
  • the exhaust pipe 41 is connected to the exhaust port. Therefore, the exhaust pipe 41 and the exhaust port constitute an exhaust passage.
  • the turbine 62 is interposed in the exhaust pipe 41 and is rotated by exhaust gas. As a result, the compressor 61 connected to the turbine 62 rotates, whereby the turbocharger 60 performs supercharging.
  • the blow-by gas recirculation device 50 includes a first gas passage portion 51, a second gas passage portion 52, and a third gas passage portion 53.
  • the first gas passage portion 51 is formed in the cylinder block 23.
  • the first gas passage portion 51 connects the crankcase chamber to the second gas passage portion 52 in the cylinder head portion 24.
  • the second gas passage portion 52 passes through a predetermined path in the cylinder head portion 24 and is connected to one end of the third gas passage portion 53.
  • the third gas passage portion 53 is constituted by a gas pipe provided outside the engine 10. The other end of the third gas passage portion 53 is the intake pipe 31 and is connected to a position upstream of the compressor 61.
  • the blow-by gas leaked from the combustion chamber CC into the crankcase chamber is recirculated (inflowed) to the intake passage portion 30 through the first gas passage portion 51, the second gas passage portion 52, and the third gas passage portion 53. It is done.
  • the third gas passage portion 53 may be provided with a well-known PCV valve (not shown).
  • FIG. 2 is a detailed sectional view of the engine 10.
  • the crankshaft 21 a includes a crank journal 211, a crankpin 212, a crank arm 213, and a balance weight 214.
  • the crank pin 212 is rotatably connected to the connecting rod 23d.
  • the crank arm 213 connects the crank journal 211 and the crank pin 212.
  • the crank arm 213 is connected to the balance weight 214.
  • the crankcase 21 includes a vertical wall portion (plate-shaped crank journal mounting portion) 21b extending from an end portion of the cylinder 23a in the axial direction of the crankshaft 21a toward the oil pan 22, and a lower end surface of the vertical wall portion. And a crank cap 21c fixed to a bolt. Therefore, the vertical wall portion 21b forms a vertical wall (vertical wall surface) parallel to the thrust direction (and anti-thrust direction) of the piston 23c. Further, a crank journal 211 is rotatably held via a bearing at a bearing portion constituted by the vertical wall portion 21b and the crank cap 21c.
  • the definitions of the thrust direction and the anti-thrust direction are the same as the definitions of the thrust direction and the anti-thrust direction that are well known in the field of internal combustion engines.
  • the cylinder liner of the conventional internal combustion engine has a cylindrical shape (a hollow cylindrical shape with the upper and lower surfaces open). Therefore, the lower end of the conventional cylinder liner (the end of the cylinder liner on the crankcase side) is flat and parallel to the axis of the crankshaft.
  • the cylinder liner 23b of the engine 10 is located below the movable region of the piston 23c (on the crankcase 21 side). It has a special shape devised so as not to generate oil mist.
  • the cylinder liner 23b is a portion of the end 23b1 on the crankcase 21 side of the cylinder liner 23b. As shown in FIG. 3D, the cylinder liner 23b is connected to the center axis of the cylinder 23a (accordingly, the cylinder liner 23b). 23b toward the first end A1 and the second end A2 that are a pair of portions overlapping the axis SC of the crankshaft 21a when viewed along the center axis CL) (ie, the first end A2).
  • the oil ring OR has a structure (lubricating oil guiding structure) for “concentrating” the lubricating oil scraped off from the inner wall of the cylinder liner 23b toward the crankcase 21. is doing.
  • the end 23b1 of the cylinder liner 23b on the crankcase 21 side is the end 23b1 of the cylinder liner 23b opposite to the cylinder head 24, and is hereinafter also referred to as “the lower end 23b1 of the cylinder liner 23b”. .
  • This naming method is used in other embodiments as well.
  • the first end A1 is a lower end 23b1 of the cylinder liner 23b and is one part of a pair of parts located in the direction of the axis SC of the crankshaft 21a.
  • the second end portion A2 is the lower end portion 23b1 of the cylinder liner 23b and is another one portion of the pair of portions located in the axis SC direction of the crankshaft 21a.
  • the reference virtual plane VP shown in (B) and (C) of FIG. 3 is defined as a plane including the axis SC of the crankshaft 21a and orthogonal to the axis CL of the cylinder 23a.
  • This definition also applies to other embodiments.
  • the thrust direction of the piston 23c is parallel to the reference virtual plane VP and is orthogonal to the axis SC direction of the crankshaft 21a.
  • the anti-thrust direction of the piston 23c is opposite to the thrust direction.
  • the shape of the lower end portion 23b1 of the cylinder liner 23b will be described in accordance with these definitions.
  • the first end A1 is separated from the reference virtual plane VP by a first distance L1.
  • the second end A2 is separated from the reference virtual plane VP by the second distance L2.
  • a thrust direction portion A3, which is a portion of the lower end portion 23b1 of the cylinder liner 23b and is located in the thrust direction of the piston 23c, is separated from the reference virtual plane VP by a third distance L3.
  • An anti-thrust direction portion A4 that is a portion of the lower end portion 23b1 of the cylinder liner 23b and is located in the anti-thrust direction of the piston 23c is separated from the reference virtual plane VP by a fourth distance L4.
  • the first distance L1 is shorter than both the third distance L3 and the fourth distance L4.
  • the second distance L2 is shorter than both the third distance L3 and the fourth distance L4.
  • the first distance L1 may be equal to or different from the second distance L2.
  • the third distance L3 may be equal to or different from the fourth distance L4.
  • the lower end portion 23b1 of the cylinder liner 23b between the first end portion A1 and the thrust direction portion A3 gradually approaches the reference virtual plane VP as it approaches the first end portion A1 from the thrust direction portion A3.
  • “the lower end portion 23b1 of the cylinder liner 23b between the first end portion A1 and the thrust direction portion A3” is smooth when the cylinder liner 23b is viewed along the thrust direction (FIG. 3B).
  • the distance between the “lower end 23b1 of the cylinder liner 23b between the first end A1 and the thrust direction part A3” and the “reference virtual plane VP” is from the thrust direction part A3 to the first end A1. It decreases monotonously as it gets closer.
  • “monotonically decreasing” is synonymous with “monotonically decreasing” used in the mathematical field.
  • the lower end portion 23b1 of the cylinder liner 23b between the second end portion A2 and the thrust direction portion A3 gradually approaches the reference virtual plane VP as it approaches the second end portion A2 from the thrust direction portion A3.
  • “the lower end portion 23b1 of the cylinder liner 23b between the second end portion A2 and the thrust direction portion A3” is smooth when the cylinder liner 23b is viewed along the thrust direction (FIG. 3B).
  • the distance between the “lower end portion 23b1 of the cylinder liner 23b between the second end portion A2 and the thrust direction portion A3” and the “reference virtual plane VP” is from the thrust direction portion A3 to the second end portion A2. It decreases monotonously as it gets closer.
  • the lower end portion 23b1 of the cylinder liner 23b between the first end portion A1 and the anti-thrust direction portion A4 gradually approaches the reference virtual plane VP as it approaches the first end portion A1 from the anti-thrust direction portion A4.
  • the distance between the “lower end 23b1 of the cylinder liner 23b between the first end A1 and the anti-thrust direction portion A4” and the “reference virtual plane VP” is the anti-thrust direction. It decreases monotonously as it approaches the first end A1 from the part A4.
  • the lower end portion 23b1 of the cylinder liner 23b between the second end portion A2 and the anti-thrust direction portion A4 gradually approaches the reference virtual plane VP as it approaches the second end portion A2 from the anti-thrust direction portion A4.
  • the distance between the “lower end 23b1 of the cylinder liner 23b between the second end A2 and the anti-thrust direction portion A4” and the “reference virtual plane VP” is the anti-thrust. It decreases monotonously as it approaches the second end A2 from the direction part A4.
  • the lubricating oil scraped off from the inner wall of the cylinder 23a (that is, the inner wall of the cylinder liner 23b) toward the crankcase 21 (and the oil pan 22) by the oil ring OR is ( It concentrates toward the first end A1 and the second end A2 (see the broken arrows in each of FIGS. 1 to 3) due to the viscosity and surface tension of the lubricating oil.
  • the lubricating oil scraped off from the inner wall of the cylinder 23a (that is, the inner wall of the cylinder liner 23b) toward the crankcase 21 (and the oil pan 22) is along the surface of the vertical wall portion (crank journal mounting portion) 21b. Since it slides down, it does not “collision and scatter while falling” on members (crank pin 212, crank arm 213, balance weight 214, connecting rod 23d, etc.) that rotate and move at high speed. Therefore, it is possible to reduce the amount of oil mist (lubricant splash) generated in the crankcase chamber.
  • the cylinder 23a has “a special shape devised so as not to generate oil mist in the crankcase chamber”.
  • the cylinder 23a is a portion of the lower end portion of the cylinder 23a (that is, the end portion on the crankcase side of the cylinder 23a), and the cylinder 23a is viewed along the cylinder axis CL.
  • lubrication is scraped off from the inner wall of the cylinder 23a toward the crankcase 21 by the oil ring toward each of the "first end portion and second end portion" which are a pair of portions overlapping the axis of the crankshaft 21a. It has a structure that concentrates oil.
  • the lubricating oil scraped off from the inner wall of the cylinder 23a toward the crankcase 21 (and the oil pan 22) slides along the vertical wall portion (crank journal mounting portion) 21b, so that it rotates and moves at high speed. There is no “clashing and scattering while falling”. Therefore, since the amount of oil mist in the crankcase chamber can be reduced, the amount of oil mist OM incorporating particulate matter such as soot can be reduced. Accordingly, it is possible to reduce the amount of deposit accumulated on the members constituting the intake passage portion 30.
  • the internal combustion engine according to the second embodiment of the present invention is an internal combustion engine only in that the shape of the cylinder liner 123 b replaced with the cylinder liner 23 b of the internal combustion engine 10 is different from the shape of the cylinder liner 23 b. It is different from the engine 10. Therefore, hereinafter, this difference will be mainly described.
  • This cylinder liner 123b has a cylindrical shape (a hollow cylindrical shape with an open upper surface and a lower surface), similar to a conventional cylinder liner. Therefore, the lower end portion (end portion of the cylinder liner 123b on the crankcase 21 side) 123b1 of the cylinder liner 123b is flat and parallel to the reference virtual plane VP.
  • the cylinder liner 123b can also be referred to as a convex portion (an “uplift portion, a protruding portion, a ridge portion, or a lubricating oil guide path forming portion”) that protrudes inward of the cylinder liner 123b on its inner wall (inner peripheral wall). ) 123b2.
  • the axis of the convex portion 123b2 is substantially the same as the line drawn by the lower end portion 23b1 of the cylinder liner 23b. Accordingly, the convex portion 123b2 is provided below (on the crankcase 21 side) the movable region of the piston 23c.
  • the convex portion 123b2 has a height (the length in the radial direction of the cylinder liner 123b) that does not hinder the movement of members (crank pin 212, crank arm 213, balance weight 214, connecting rod 23d, etc.) that rotate and move at high speed. A).
  • the convex portion 123b2 is formed on the crankshaft 21a when the cylinder liner 123b is viewed along the center axis of the cylinder (accordingly, the center axis CL1 of the cylinder liner 123b).
  • a cylinder liner is connected to each of the “first end B1 and second end B2” (that is, to both the first end B1 and the second end B2) which are a pair of portions overlapping the axis SC by an oil ring OR. It extends so as to have a structure / shape (lubricating oil guiding structure) for concentrating lubricating oil scraped off from the inner wall of 123b toward the crankcase 21.
  • the shape of the cross section perpendicular to the axis of the convex portion 123b2 is a substantially rectangular shape as shown in FIG.
  • the length of the convex portion 123b2 in the “direction along the central axis CL1 of the cylinder liner 123b” is constant “H”.
  • the length of the convex portion 123b2 in the “direction toward the central axis CL1 of the cylinder liner 123b” is constant “L”. As shown in FIG.
  • the shape of the cross section orthogonal to the axis of the convex portion 123b2 is that the bottom portion T1 extends in the direction of the central axis CL1 of the cylinder liner 123b, and the cylinder liner extends from the end of the bottom portion T1. It may have a slope portion T2 that is bent obliquely toward the upper end (cylinder head side) of 123b.
  • the shape of the convex portion 123b2 will be described more specifically with reference to FIG.
  • the first end B1 is a lower end 123b1 of the cylinder liner 123b and is one part of a pair of parts located in the axis SC direction of the crankshaft 21a.
  • the second end B2 is the lower end 123b1 of the cylinder liner 123b, and is another part of the pair of parts located in the direction of the axis SC of the crankshaft 21a.
  • the convex portion 123b2 is provided in a portion excluding the predetermined region including the first end B1 and the predetermined region including the second end B2.
  • the convex portion 123b2 is symmetric with respect to a plane including the axis CL1 of the cylinder liner 123b and the axis SC of the crankshaft 21a. Accordingly, hereinafter, the shape of the convex portion 123b2 provided on the side opposite to the thrust direction of the cylinder liner 123b will be described.
  • the upper surface of the end portion (the first end portion vicinity portion) closest to the first end portion B1 of the convex portion 123b2 is separated from the reference virtual plane VP by the first distance L11.
  • the upper surface of the end portion (second end vicinity portion) closest to the second end B2 of the convex portion 123b2 is separated from the reference virtual plane VP by the first distance L12.
  • the upper surface of the anti-thrust direction portion B4 which is the portion of the convex portion 123b2 located in the anti-thrust direction of the piston 23c, is separated from the reference virtual plane VP by the fourth distance L14.
  • the first distance L11 is shorter than the fourth distance L14.
  • the second distance L12 is shorter than the fourth distance L14.
  • the first distance L11 may be equal to or different from the second distance L12.
  • the upper surface of the convex portion 123b2 between the vicinity of the first end portion and the anti-thrust direction portion B4 gradually approaches the reference virtual plane VP as it approaches the vicinity of the first end portion from the anti-thrust direction portion B4.
  • the upper surface of the convex portion 123b2 between the vicinity of the second end portion and the anti-thrust direction portion B4 gradually approaches the reference virtual plane VP from the anti-thrust direction portion B4 toward the vicinity of the second end portion.
  • the lubricating oil scraped off from the inner wall of the cylinder 23a that is, the inner wall of the cylinder liner 123b
  • the crankcase 21 and the oil pan 22
  • the oil ring OR It concentrates toward the 1st edge part B1 and 2nd edge part B2 (refer the arrow of the broken line in FIG. 5).
  • the lubricating oil scraped off from the inner wall of the cylinder 23a that is, the inner wall of the cylinder liner 123b) toward the crankcase 21 (and the oil pan 22) flows along the upper surface of the convex portion 123b2 and becomes “first It concentrates toward the end portion B1 and the second end portion B2 ", and then slides down along the surface of the vertical wall portion (crank journal mounting portion) 21b. Therefore, the lubricant to be scraped off does not “collision and scatter while falling” to members (crank pin 212, crank arm 213, balance weight 214, connecting rod 23d, etc.) rotating and moving at high speed. .
  • the cylinder liner 223b which replaces the cylinder liner 123b, includes the “concave portion 223b2 whose cross-sectional shape is shown in FIG. 7” instead of the convex portion 123b2.
  • the axis of the concave portion 223b2 is substantially the same as the axis of the convex portion 123b2 of the cylinder liner 123b.
  • the concave portion 223b2 is provided below the movable region of the piston 23c (on the crankcase 21 side). It can also be said that the concave portion 223b2 is a groove (lubricating oil guide path forming portion) formed in the inner wall (inner peripheral wall) of the cylinder liner 223b.
  • the lubricating oil scraped off from the inner wall of the cylinder 23a (that is, the inner wall of the cylinder liner 123b) toward the crankcase 21 by the oil ring OR flows along the concave portion 223b2, and the first end. It concentrates toward the part B1 and the second end part B2, and then slides down along the surface of the vertical wall part (crank journal attaching part) 21b. Therefore, the lubricant to be scraped off does not “collision and scatter while falling” on a member that is rotating and moving at high speed. As a result, for the same reason as in the first embodiment and the second embodiment, it is possible to reduce the amount of deposit deposited on the members constituting the intake passage portion 30.
  • the cylinder liner 323b has a cylindrical shape (a hollow cylindrical shape with an open upper surface and a lower surface) as in the conventional cylinder liner. Accordingly, the lower end portion of the cylinder liner 323b (the end portion of the cylinder liner 323b on the crankcase 21 side) 323b1 is flat and parallel to the reference virtual plane VP.
  • the cylinder liner 323b is provided with a collar portion 323b2 projecting inward (in the direction of the central axis CL3 of the cylinder liner 323b) from the lower end portion 323b1 at the lower end portion 323b1 of the cylinder liner 323b.
  • the flange 323b2 has a position and a length (the length of the cylinder liner 323b in the radial direction) that does not hinder the movement of the members (crank pin 212, crank arm 213, balance weight 214, connecting rod 23d, etc.) that rotate and move at high speed. A).
  • the flange portion 323b2 is a portion of the lower end portion 323b1 of the cylinder liner 323b, and when the cylinder liner 323b is viewed along the center axis of the cylinder 23a (therefore, the center axis CL3 of the cylinder liner 323b) (see FIG. 8). (See (B).), “First end portion C1 and second end portion C2” that are portions of a pair of portions overlapping the axis SC of the crankshaft 21a (ie, the first end portion C1 and the second end portion). It is provided in a portion excluding a predetermined region including both of the part C2.
  • the lubricating oil scraped off from the inner wall of the cylinder liner 323b toward the crankcase 21 by the oil ring OR is “concentrated” toward a predetermined region including each of the “first end C1 and second end C2”.
  • the flange 323b2 has a lubricating oil guiding structure that concentrates the lubricating oil on each of the “first end C1 and second end C2”.
  • the lubricating oil scraped off toward the crankcase 21 slides along the surface of the vertical wall portion (crank journal mounting portion) 21b. Therefore, the lubricant to be scraped off does not “collision and scatter while falling” on a member that is rotating and moving at high speed. As a result, for the same reason as in the first embodiment and the second embodiment, it is possible to reduce the amount of deposit deposited on the members constituting the intake passage portion 30.
  • the shape of the cylinder liner 423b replaced with the cylinder liner 23b of the internal combustion engine 10 is the same as that of the cylinder liner 23b. It differs from the internal combustion engine 10 only in the point different from the shape. Therefore, hereinafter, this difference will be mainly described.
  • the cylinder liner 423b is a portion of the end portion 423b1 of the cylinder liner 423b on the crankcase 21 side, and the cylinder liner 423b is viewed along the center axis of the cylinder 23a (therefore, the center axis CL4 of the cylinder liner 423b) ( 9D), only one of “first end D1 and second end D2” that is a pair of portions overlapping the axis SC of the crankshaft 21a (in this case, the first end portion).
  • D1 only) has a structure (lubricating oil guiding structure) for “concentrating” the lubricating oil scraped off from the inner wall of the cylinder liner 423b toward the crankcase 21 by the oil ring OR.
  • first end D1 is separated from the reference virtual plane VP by the fifth distance L41.
  • the second end D2 is separated from the reference virtual plane VP by “a sixth distance L42 longer than the fifth distance L41”.
  • the lower end portion 423b1 of the cylinder liner 423b between the first end portion D1 and the second end portion D2 gradually approaches the reference virtual plane VP from the second end portion D2 toward the first end portion D1.
  • the lower end 423b1 of the cylinder liner 423b between the first end D1 and the second end D2 is viewed when the cylinder liner 423b is viewed along the thrust direction (or anti-thrust direction) ( B).
  • the distance between the lower end 423b1 of the cylinder liner 423b and the reference virtual plane VP between the first end D1 and the second end D2 is the second end D2. Decreases monotonically as it approaches the first end D1.
  • the lubricating oil scraped off from the inner wall of the cylinder 23a (that is, the inner wall of the cylinder liner 423b) toward the crankcase 21 by the oil ring OR is directed toward the first end D1. (See the dashed arrows in FIG. 9).
  • the lubricating oil scraped off by the oil ring OR flows along the lower end portion of the cylinder liner 423b and concentrates toward the first end portion D1, and then the vertical wall portion (crank journal mounting portion) 21b. Slide down along the surface. Therefore, the lubricant to be scraped off does not “collision and scatter while falling” to members (crank pin 212, crank arm 213, balance weight 214, connecting rod 23d, etc.) rotating and moving at high speed. . As a result, for the same reason as in the first embodiment and the second embodiment, it is possible to reduce the amount of deposit deposited on the members constituting the intake passage portion 30.
  • ⁇ Modification of Fifth Embodiment> when the internal combustion engine 10 is an engine that does not include a cylinder liner, a lower end portion (crankcase) of a cylinder (bore) formed by the cylinder block 23 instead of the cylinder liner 423b.
  • the end portion on the 21st side is different from the fifth embodiment only in that it has the same shape as the cylinder liner 423b of the fifth embodiment.
  • the lubricating oil scraped off from the inner wall of the cylinder 23a toward the crankcase 21 slides along the vertical wall portion (crank journal mounting portion) 21b, so that it “drops” on the member that rotates and moves at high speed. "There is no collision and scattering". Therefore, since the amount of oil mist in the crankcase chamber can be reduced, the amount of oil mist OM incorporating particulate matter such as soot can be reduced. Accordingly, it is possible to reduce the amount of deposit accumulated on the members constituting the intake passage portion 30.
  • the sixth embodiment of the present invention differs from the fifth embodiment only in that the shape of the cylinder liner 523b replaced with the cylinder liner 423b is different from the shape of the cylinder liner 423b. . Therefore, hereinafter, this difference will be mainly described.
  • the cylinder liner 523b has a cylindrical shape (a hollow cylindrical shape with an open upper surface and a lower surface) as in the conventional cylinder liner. Therefore, the lower end portion of the cylinder liner 523b (the end portion of the cylinder liner 523b on the crankcase 21 side) 523b1 is flat and parallel to the reference virtual plane VP.
  • the cylinder liner 523b can also be referred to as a projecting portion ("a raised portion, a protruding portion, a ridge portion, or a lubricating oil guide path forming portion") that protrudes inward of the cylinder liner 523b on its inner wall (inner peripheral wall). ) 523b2.
  • the convex portion 523b2 extends so that the axis of the convex portion 523b2 is substantially the same as the “line drawn by the lower end portion 23b1 of the cylinder liner 423b”. Accordingly, the convex portion 523b2 is provided below the movable region of the piston 23c (on the crankcase 21 side).
  • the convex portion 523b2 has a height (the length of the cylinder liner 523b in the radial direction) that does not hinder the movement of members (crank pin 212, crank arm 213, balance weight 214, connecting rod 23d, etc.) that rotate and move at high speed. A).
  • the convex portion 523b2 has the axis of the crankshaft 21a when the cylinder liner 523b is viewed along the center axis of the cylinder (therefore, the center axis CL5 of the cylinder liner 523b) (see FIG. 10A). Crank from the inner wall of the cylinder liner 523b by an oil ring OR to only one of the first end E1 and the second end E2 (in this case, only the first end E1) that is a pair of portions overlapping the SC. It extends so as to have a structure / shape (lubricating oil guiding structure) that “concentrates” the lubricating oil scraped off toward the case 21.
  • a structure / shape lubricating oil guiding structure
  • the shape of the cross section orthogonal to the axis of the convex portion 523b2 may be a substantially rectangular shape as shown in FIG. 10B, and is the same shape as the shape shown in FIG. 523b having a bottom portion T1 extending in the direction of the central axis CL5, and a slope portion T2 that is obliquely bent from the end portion of the bottom portion T1 toward the upper end (cylinder head side) of the cylinder liner 523b). Also good.
  • the convex portion 523b2 is provided in a portion excluding a predetermined region including the first end E1.
  • the distance L51 between the upper surface (cylinder head side surface) of the convex portion 523b2 near the first end E1 and the reference virtual plane VP is equal to the upper surface of the convex portion 523b2 and the reference virtual plane VP at the second end E3. Is smaller than the distance L52.
  • the upper surface of the convex portion 523b2 gradually approaches the reference virtual plane VP as it approaches the first end E1 from the second end E2.
  • the upper surface of the convex portion 523b2 between the first end E1 and the second end E2 is viewed from the cylinder liner 523b along the thrust direction (or anti-thrust direction) ((B of FIG. 10).
  • the distance between the upper surface of the cylinder liner 523b and the reference virtual plane VP between the first end E1 and the second end E2 is the first end E2 to the first end E2. It decreases monotonously as it approaches the end E1.
  • the lubricating oil scraped off by the oil ring OR flows along the upper surface of the convex portion 523b2 and concentrates toward the first end E1, and then the vertical wall portion (crank journal mounting portion) 21b. Slide down along the surface. Therefore, the lubricant to be scraped off does not “collision and scatter while falling” to members (crank pin 212, crank arm 213, balance weight 214, connecting rod 23d, etc.) rotating and moving at high speed. . As a result, for the same reason as in the first embodiment and the second embodiment, it is possible to reduce the amount of deposit deposited on the members constituting the intake passage portion 30.
  • a cylinder liner 623b replacing the cylinder liner 523b includes a “concave portion 623b2 whose sectional shape is shown in FIG. 11” instead of the convex portion 523b2.
  • the concave portion 623b2 extends so that the axis of the concave portion 623b2 is substantially the same as the axis of the convex portion 523b2 of the cylinder liner 523b.
  • the concave portion 623b2 is provided below (on the crankcase 21 side) the movable region of the piston 23c.
  • the recessed portion 623b2 is a groove (lubricating oil guide path forming portion) formed in the inner wall (inner peripheral wall) of the cylinder liner 223b.
  • the lubricating oil scraped off from the inner wall of the cylinder 23a (that is, the inner wall of the cylinder liner 623b) toward the crankcase 21 by the oil ring OR flows along the concave portion 623b2, and the first end. It concentrates toward the part E1, and then slides down along the surface of the vertical wall part (crank journal attaching part) 21b. Therefore, the lubricant to be scraped off does not “collision and scatter while falling” on a member that is rotating and moving at high speed. As a result, for the same reason as in the first embodiment and the second embodiment, it is possible to reduce the amount of deposit deposited on the members constituting the intake passage portion 30.
  • the cylinder liner 723b replaced with the cylinder liner 23b of the internal combustion engine 10 has a cylinder liner 23b shape. It differs from the internal combustion engine 10 only in the point different from the shape. Therefore, hereinafter, this difference will be mainly described.
  • This cylinder liner 723b has a cylindrical shape (a hollow cylindrical shape with the upper surface and the lower surface opened) as in the conventional cylinder liner. Accordingly, the lower end portion of the cylinder liner 723b (the end portion of the cylinder liner 723b on the crankcase 21 side) 723b1 is flat and parallel to the reference virtual plane VP.
  • the cylinder liner 723b is provided with a collar portion 723b2 projecting inward (in the direction of the central axis CL7 of the cylinder liner 723b) from the lower end portion 723b1 at the lower end portion 723b1 of the cylinder liner 723b.
  • the flange portion 723b2 has a position and a length (the length of the cylinder liner 723b in the radial direction) that does not hinder the movement of members (crank pin 212, crank arm 213, balance weight 214, connecting rod 23d, etc.) that rotate and move at high speed. A).
  • the flange portion 323b2 is a portion of the lower end portion 323b1 of the cylinder liner 323b, and when the cylinder liner 723b is viewed along the center axis of the cylinder 23a (therefore, the center axis CL7 of the cylinder liner 723b) (see FIG. 12). (See (B).), Provided in a portion excluding the “predetermined region including the first end portion F1” that is a pair of portions overlapping the axis SC of the crankshaft 21a.
  • the lubricating oil scraped off from the inner wall of the cylinder liner 723b toward the crankcase 21 by the oil ring OR is “concentrated” toward the “predetermined region including the first end portion F1”. That is, the flange portion 723b2 has a “lubricating oil guiding structure that concentrates the lubricating oil toward the first end portion F1”.
  • the lubricating oil scraped off toward the crankcase 21 slides along the surface of the vertical wall portion (crank journal mounting portion) 21b. Therefore, the lubricant to be scraped off does not “collision and scatter while falling” on a member that is rotating and moving at high speed. As a result, for the same reason as in the first embodiment and the second embodiment, it is possible to reduce the amount of deposit deposited on the members constituting the intake passage portion 30.
  • the internal combustion engine according to each embodiment of the present invention is the lower end portion (the end portion on the crankcase side) of the inner wall of the cylinder (the inner wall of the cylinder liner or the cylinder itself) in the crankshaft direction.
  • the lubricating oil scraped off from the inner wall of the cylinder toward the crankcase by the oil ring OR is concentrated toward at least one of the pair of first and second end portions.
  • the lubricating oil scraped off from the inner wall of the cylinder toward the crankcase does not drop, collide, or scatter on members that rotate and move at high speed (such as crank arms, crank pins, balance weights and / or connecting rods). . Therefore, the amount of oil mist generated in the crankcase can be reduced, and as a result, the amount of deposit attached to the intake passage constituting member can be reduced.
  • the present invention is not limited to the above embodiment, and various modifications can be employed within the scope of the present invention.
  • a “strip-like film having very good wettability with the lubricating oil” may be formed on the portion where the convex portion exists.
  • the present invention may be applied to a V-type engine.
  • the present invention can also be applied to an internal combustion engine that does not include a turbocharger.
  • the cylinder liner 23b shown in FIG. 3 has a cylinder portion 23b1 at the lower end portion 23b1 except for both the “predetermined region including the first end portion A1 and the predetermined region including the second end portion A2”. You may have the collar part "extended in the central axis CL direction of a cylinder liner from the inner wall of the liner 23b.
  • the cylinder liner 423b shown in FIG. 9 has a lower end portion 423b1 other than the “predetermined region including the first end portion D1” in the direction from the inner wall of the cylinder liner 423b toward the centerline CL4 of the cylinder liner. You may have an extending heel part.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Lubrication Details And Ventilation Of Internal Combustion Engines (AREA)

Abstract

An internal combustion engine (10) according to one embodiment of the present invention is a piston reciprocating internal combustion engine wherein a piston (23c) provided with an oil ring (OR) moves reciprocally within a cylinder (23a). The internal combustion engine (10) is equipped with a cylinder inner wall part (a cylinder liner (23b)) forming the inner wall of the cylinder, and a blow-by gas recirculation device (50) that recirculates blow-by gas in the crankcase (21) housing the crankshaft to the intake passage of the internal combustion engine (10). Furthermore, the cylinder liner (23b) is constructed such that lubricating oil scraped toward the crankcase (21) from the inner wall of the cylinder liner (23) by the oil ring (OR) is concentrated toward at least one of a pair of parts (that is, a first end part and a second end part), which are the end parts of the inner wall of the cylinder liner (the lower end parts of the cylinder liner) on the crankshaft (21a) side, and are located in the axial direction of the crankshaft (21a).

Description

ブローバイガス還流装置を備える内燃機関Internal combustion engine provided with blow-by gas recirculation device
　本発明は、クランクケース内のブローバイガスを吸気通路へ還流（流入）させるブローバイガス還流装置、を備えるピストン往復動型内燃機関に関する。 The present invention relates to a piston reciprocating internal combustion engine including a blow-by gas recirculation device that recirculates (inflows) blow-by gas in a crankcase into an intake passage.
　従来から、ピストン往復動型内燃機関（以下、単に「内燃機関」又は「機関」とも称呼する。）の燃焼室からクランクケース内に漏出したブローバイガスを吸気通路に還流させることにより、クランクケース内の換気を行うシステムが知られている。係るシステムは、「ブローバイガス還流装置」又は「ＰＣＶ（ポジティブ・クランクケース・ベンチレーション）」とも称呼される（例えば、特許文献１を参照。）。 Conventionally, the blow-by gas leaked from the combustion chamber of a piston reciprocating internal combustion engine (hereinafter also simply referred to as “internal combustion engine” or “engine”) into the crank case is recirculated to the intake passage, thereby Systems for ventilating the air are known. Such a system is also referred to as “blow-by gas recirculation device” or “PCV (positive crankcase ventilation)” (see, for example, Patent Document 1).
　ところで、ブローバイガスには煤（ｓｏｏｔ）等の微粒子（パティキュレートマター、ＰＭ）が含まれている。パティキュレートマターの径は例えば０．１μｍ程度である。一方、クランクケース内においてはオイルミスト（潤滑油の液体状微粒子）が発生している。このオイルミストの径は例えば５μｍ程度であって、パティキュレートマターの径よりも大きい。その結果、図１３の（Ａ）に示したように、パティキュレートマターＰＭはオイルミストＯＭに取り込まれオイルミストＯＭ内に分布（存在）するようになる。 By the way, blow-by gas contains fine particles (particulate matter, PM) such as soot. The diameter of the particulate matter is, for example, about 0.1 μm. On the other hand, oil mist (liquid fine particles of lubricating oil) is generated in the crankcase. The diameter of the oil mist is, for example, about 5 μm and is larger than the diameter of the particulate matter. As a result, as shown in FIG. 13A, the particulate matter PM is taken into the oil mist OM and distributed (exists) in the oil mist OM.
　このオイルミストＯＭは、ブローバイガス還流装置によってクランクケースから吸気通路へと還流される。このとき、オイルミストＯＭは受熱するので、オイルミストＯＭ中の蒸発し易い成分が蒸発する。従って、図１３の（Ｂ）に示したように、オイルミストＯＭは小径化し、オイルミストＯＭ中のパティキュレートマターＰＭの密度が増大する。よって、パティキュレートマターＰＭを含むオイルミストＯＭは他の部材に付着し易くなる。 This oil mist OM is recirculated from the crankcase to the intake passage by a blow-by gas recirculation device. At this time, since the oil mist OM receives heat, the easily evaporated component in the oil mist OM evaporates. Therefore, as shown in FIG. 13B, the diameter of the oil mist OM is reduced, and the density of the particulate matter PM in the oil mist OM is increased. Therefore, the oil mist OM including the particulate matter PM is likely to adhere to other members.
　そのため、、図１３の（Ｃ）及び（Ｄ）に示したように、その小径化した「パティキュレートマターＰＭを含むオイルミストＯＭ」は吸気通路を構成する部材（以下、「吸気通路構成部材」とも称呼する。）に付着して固体状（又はゲル状）となる。即ち、吸気通路構成部材にデポジットが発生する。係るデポジットは機関の特性上好ましくない。特に、吸気通路にターボチャージャのコンプレッサが設けられている場合、オイルミストＯＭはコンプレッサ内において急激に高温となって小径化するので、オイルミストＯＭにおけるパティキュレートマターＰＭの密度が大きく上昇する。その結果、パティキュレートマターがターボチャージャのディフューザ等に多量に付着し、ターボチャージャの効率が著しく低下する虞がある。 Therefore, as shown in FIGS. 13C and 13D, the reduced “oil mist containing particulate matter PM” is a member constituting the intake passage (hereinafter referred to as “intake passage constituting member”). To form a solid (or gel). That is, a deposit is generated in the intake passage constituting member. Such a deposit is not preferable due to the characteristics of the engine. In particular, when a turbocharger compressor is provided in the intake passage, the oil mist OM rapidly increases in temperature in the compressor and decreases in diameter, so that the density of the particulate matter PM in the oil mist OM greatly increases. As a result, a large amount of particulate matter may adhere to the diffuser of the turbocharger and the efficiency of the turbocharger may be significantly reduced.
特開２０００－８８２８号公報Japanese Patent Laid-Open No. 2000-8828
　本発明は上記課題に対処するためになされたものである。即ち、本発明の目的の一つは、クランクケース内に発生するオイルミストの量を低減させることによって、吸気通路構成部材に発生（付着）するデポジットの量を低減することが可能なピストン往復動型内燃機関を提供することにある。 The present invention has been made to address the above-described problems. That is, one of the objects of the present invention is a piston reciprocating motion capable of reducing the amount of deposit generated (attached) to the intake passage constituting member by reducing the amount of oil mist generated in the crankcase. An internal combustion engine is provided.
　本発明による内燃機関は、オイルリングが設けられたピストンがシリンダ内を往復動する機関であり、前記シリンダの内壁を構成するシリンダ内壁部と、クランクシャフトを収容するクランクケース内のブローバイガスを前記機関の吸気通路へ還流させるブローバイガス還流装置と、を備える。 An internal combustion engine according to the present invention is an engine in which a piston provided with an oil ring reciprocates in a cylinder, and a cylinder inner wall portion constituting an inner wall of the cylinder and a blow-by gas in a crankcase that houses a crankshaft are A blow-by gas recirculation device for recirculating to the intake passage of the engine.
　シリンダ内壁部は、内燃機関がシリンダライナを備える場合にはシリンダライナであり、内燃機関がシリンダライナを備えない場合には機関本体のシリンダボアを形成している部分を指す。 The cylinder inner wall portion is a cylinder liner when the internal combustion engine is provided with a cylinder liner, and indicates a portion that forms a cylinder bore of the engine body when the internal combustion engine is not provided with a cylinder liner.
　更に、本発明においては、前記シリンダ内壁部がオイルミストの発生量を低減する特殊構造を備える。即ち、前記シリンダ内壁部が、前記オイルリングにより前記シリンダの内壁から前記クランクケースに向けて掻き落とされる潤滑油を、「前記シリンダの内壁の前記クランクケース側の端部の部分（シリンダの内壁のシリンダヘッド側と反対側の端部、即ち、シリンダの内壁の下端部）」であって、「前記シリンダ内壁部を前記シリンダの軸線に沿って見た場合に（即ち、前記シリンダ内壁部の上面視において）前記クランクシャフトの軸線と重なる一対の部分」である「第１端部及び第２端部」の少なくとも一方に向けて、集中させる構造を有している。 Furthermore, in the present invention, the cylinder inner wall portion has a special structure for reducing the amount of oil mist generated. That is, the cylinder inner wall portion removes lubricating oil scraped off from the inner wall of the cylinder toward the crankcase by the oil ring, “the portion of the inner wall of the cylinder on the crankcase side (the inner wall of the cylinder "The end opposite to the cylinder head side, that is, the lower end of the inner wall of the cylinder)", and "when the cylinder inner wall is viewed along the axis of the cylinder (that is, the upper surface of the cylinder inner wall). (When viewed) it has a structure in which it is concentrated toward at least one of “a first end and a second end” which is a “pair of portions overlapping with the axis of the crankshaft”.
　この内燃機関によれば、オイルリングによりシリンダの内壁からクランクケースに向けて掻き落とされる潤滑油が、「前記第１端部及び前記第２端部」の少なくとも一方へ向けて集められる。前記第１端部及び前記第２端部は、何れも「クランクシャフトジャーナルの取付け部（軸受け部）」へと連続している。従って、クランクケースに向けて掻き落とされる潤滑油は、第１端部又は第２端部からクランクシャフトジャーナルの取付け部の壁面に沿って流れ、その後、オイルパン内に落下する。従って、クランクケースに向けて掻き落とされる潤滑油が、高速で回転・運動している部材（クランクアーム、クランクピン、バランスウエイト及び／又はコネクティングロッド等）に「落下しながら衝突して飛散する」ことがない。その結果、クランクケース内に発生するオイルミスト（オイルの飛沫）の量を低減できるので、吸気通路構成部材に付着するデポジットの量を低減することができる。 According to this internal combustion engine, the lubricating oil scraped off from the inner wall of the cylinder toward the crankcase by the oil ring is collected toward at least one of the “first end portion and the second end portion”. The first end portion and the second end portion are both continuous to a “crankshaft journal mounting portion (bearing portion)”. Therefore, the lubricating oil scraped off toward the crankcase flows along the wall surface of the mounting portion of the crankshaft journal from the first end or the second end, and then falls into the oil pan. Therefore, the lubricant that is scraped off toward the crankcase “collises and scatters while falling” on members (crank arms, crankpins, balance weights and / or connecting rods, etc.) that rotate and move at high speed. There is nothing. As a result, since the amount of oil mist (oil splash) generated in the crankcase can be reduced, the amount of deposit attached to the intake passage constituting member can be reduced.
　なお、本明細書及び請求の範囲において、オイルリングにより掻き落とされる潤滑油が「特定端部」に向けて集中するとは、オイルリングにより掻き落とされる潤滑油の大部分が特定端部に集まることを意味する。換言すると、オイルリングにより掻き落とされる潤滑油が「特定端部」に向けて集中することは、オイルリングにより掻き落とされる潤滑油のうち「特定端部を含む所定領域」以外の部分からクランクケース側に落下する潤滑油の量が、オイルリングにより掻き落とされる潤滑油のうち「特定端部を含む所定領域」からクランクケース側に落下する潤滑油の量に比べて極めて少ないことを意味し、従って、「特定端部を含む所定領域」以外の部分からクランクケース側に落下する潤滑油が皆無であることを意味しない。 In the present specification and claims, the fact that the lubricating oil scraped off by the oil ring concentrates toward the “specific end” means that most of the lubricating oil scraped off by the oil ring collects at the specific end. Means. In other words, the fact that the lubricating oil scraped off by the oil ring concentrates toward the “specific end” means that the portion of the lubricating oil scraped off by the oil ring from the portion other than the “predetermined region including the specific end” This means that the amount of lubricant that falls to the side is very small compared to the amount of lubricant that falls to the crankcase side from the `` predetermined region including the specific end portion '' of the lubricant that is scraped off by the oil ring, Therefore, it does not mean that there is no lubricating oil falling from the portion other than the “predetermined region including the specific end portion” to the crankcase side.
　この場合、前記シリンダ内壁部は、前記掻き落とされる潤滑油を前記第１端部及び前記第２端部のそれぞれ（即ち、前記第１及び第２端部の双方）に向けて集中させる構造を有することができる。 In this case, the cylinder inner wall portion has a structure that concentrates the scraped lubricating oil toward each of the first end portion and the second end portion (that is, both the first end portion and the second end portion). Can have.
　係る内燃機関の一態様において、
　前記シリンダ内壁部は、前記シリンダの内壁の前記クランクシャフト側の端部（シリンダの内壁の下端部）が「前記掻き落とされる潤滑油を前記第１端部及び前記第２端部のそれぞれに向けて集中させる形状」を有するように、構成される。 In one aspect of the internal combustion engine,
The cylinder inner wall portion has an end portion on the crankshaft side of the inner wall of the cylinder (a lower end portion of the inner wall of the cylinder) that directs the lubricant to be scraped off to each of the first end portion and the second end portion. To have a “concentrated shape”.
　これによれば、シリンダの内壁の下端部（例えば、シリンダライナの下端部又はシリンダを構成している機関本体部分の下端部）の形状を変更するだけで、クランクケース内に発生するオイルミストの量を低減することができる。 According to this, the oil mist generated in the crankcase is simply changed by changing the shape of the lower end portion of the inner wall of the cylinder (for example, the lower end portion of the cylinder liner or the lower end portion of the engine main body constituting the cylinder). The amount can be reduced.
　より具体的に述べると、前記シリンダ内壁部は、以下に述べるように構成され得る。
・前記第１端部が、前記クランクシャフトの軸線を含む平面であって前記シリンダの軸線と直交する平面である基準仮想平面から第１距離だけ離間する。
・前記第２端部が、前記基準仮想平面から第２距離だけ離間する。
・前記シリンダの内壁の前記クランクケース側の端部の部分であって前記ピストンのスラスト方向に位置する部分であるスラスト方向部は、前記基準仮想平面から第３距離だけ離間する。
・前記シリンダの内壁の前記クランクケース側の端部の部分であって前記ピストンの反スラスト方向に位置する部分である反スラスト方向部が、前記基準仮想平面から第４距離だけ離間する。 More specifically, the cylinder inner wall can be configured as described below.
The first end portion is separated from a reference virtual plane which is a plane including the axis of the crankshaft and is orthogonal to the axis of the cylinder by a first distance.
The second end portion is separated from the reference virtual plane by a second distance;
A thrust direction portion, which is a portion of the inner wall of the cylinder on the crankcase side and is located in the thrust direction of the piston, is separated from the reference virtual plane by a third distance.
An anti-thrust direction portion that is a portion of the inner wall of the cylinder on the crankcase side and is located in the anti-thrust direction of the piston is separated from the reference virtual plane by a fourth distance.
・前記第１距離が前記第３距離及び前記第４距離の何れよりも短い。
・前記第２距離が前記第３距離及び前記第４距離の何れよりも短い。 The first distance is shorter than any of the third distance and the fourth distance.
The second distance is shorter than any of the third distance and the fourth distance.
・前記第１端部と前記スラスト方向部との間の前記シリンダの内壁の前記クランクケース側の端部が、前記スラスト方向部から前記第１端部に近づくにつれて前記基準仮想平面に徐々に近づく形状を有する。
・前記第２端部と前記スラスト方向部との間の前記シリンダの内壁の前記クランクケース側の端部が、前記スラスト方向部から前記第２端部に近づくにつれて前記基準仮想平面に徐々に近づく形状を有する。
・前記第１端部と前記反スラスト方向部との間の前記シリンダの内壁の前記クランクケース側の端部が、前記反スラスト方向部から前記第１端部に近づくにつれて前記基準仮想平面に徐々に近づく形状を有する。
・前記第２端部と前記反スラスト方向部との間の前記シリンダの内壁の前記クランクケース側の端部が、前記反スラスト方向部から前記第２端部に近づくにつれて前記基準仮想平面に徐々に近づく形状を有する。 The end on the crankcase side of the inner wall of the cylinder between the first end and the thrust direction portion gradually approaches the reference virtual plane as it approaches the first end from the thrust direction portion. Has a shape.
The end on the crankcase side of the inner wall of the cylinder between the second end and the thrust direction portion gradually approaches the reference virtual plane as it approaches the second end from the thrust direction portion. Has a shape.
The end on the crankcase side of the inner wall of the cylinder between the first end and the anti-thrust direction portion gradually approaches the reference virtual plane as it approaches the first end from the anti-thrust direction portion. It has a shape that approaches.
The end on the crankcase side of the inner wall of the cylinder between the second end and the anti-thrust direction portion gradually approaches the reference virtual plane as it approaches the second end from the anti-thrust direction portion. It has a shape that approaches.
　この構造によれば、前記オイルリングにより前記シリンダの内壁から前記クランクケースに向けて掻き落とされる潤滑油は、その大部分が前記シリンダの内壁の下端部に沿って第１及び第２端部に向けて移動し、その後、第１及び第２端部近傍からクランクケース側へと「クランクシャフトジャーナルの取付け部」に沿って移動する。従って、クランクケース内に発生するオイルミスト（オイルの飛沫）の量を低減することができる。 According to this structure, most of the lubricating oil scraped off from the inner wall of the cylinder toward the crankcase by the oil ring is directed to the first and second end portions along the lower end portion of the inner wall of the cylinder. Then, it moves along the “mounting portion of the crankshaft journal” from the vicinity of the first and second ends toward the crankcase side. Therefore, the amount of oil mist (oil splash) generated in the crankcase can be reduced.
　前記掻き落とされる潤滑油を前記第１及び前記第２端部のそれぞれに向けて集中させる構造の他の態様においては、前記シリンダ内壁部が以下に述べる構造を有するように構成される。
・前記シリンダの内壁の前記クランクケース側の端部が、前記クランクシャフトの軸線を含む平面であって前記シリンダの軸線と直交する平面である基準仮想平面と平行である。
・前記シリンダの内壁の前記クランクケース側の端部が、「前記第１端部を含む第１領域」及び「前記第２端部を含む第２領域」の両領域を除く部分に「前記シリンダの内壁から前記シリンダの軸線方向に延びる庇部」を備える。 In another aspect of the structure in which the scraped lubricating oil is concentrated toward each of the first and second end portions, the cylinder inner wall portion is configured to have a structure described below.
The end of the inner wall of the cylinder on the crankcase side is parallel to a reference virtual plane that is a plane that includes the axis of the crankshaft and is orthogonal to the axis of the cylinder.
The end of the inner wall of the cylinder on the crankcase side is located in a portion excluding both the “first region including the first end” and the “second region including the second end”. A flange portion extending in the axial direction of the cylinder from the inner wall of the cylinder.
　この構造によれば、前記オイルリングにより前記シリンダの内壁から前記クランクケースに向けて掻き落とされる潤滑油は、シリンダの内壁の下端部に設けられた庇部に到達し、庇部に沿って第１及び第２端部に向けて移動し、その後、第１及び第２端部近傍からクランクケース側へと「クランクシャフトジャーナルの取付け部」に沿って移動する。従って、クランクケース内に発生するオイルミスト（オイルの飛沫）の量を低減することができる。 According to this structure, the lubricating oil scraped off from the inner wall of the cylinder toward the crankcase by the oil ring reaches the flange portion provided at the lower end portion of the inner wall of the cylinder, and is changed along the flange portion. It moves toward the first and second ends, and then moves along the “mounting portion of the crankshaft journal” from the vicinity of the first and second ends to the crankcase side. Therefore, the amount of oil mist (oil splash) generated in the crankcase can be reduced.
　前記掻き落とされる潤滑油を前記第１及び前記第２端部のそれぞれに向けて集中させる構造の他の態様においては、前記シリンダ内壁部は、「前記シリンダの内壁から前記シリンダの内部に向けて突出する凸状部」であって「前記掻き落とされる潤滑油を前記第１端部及び前記第２端部のそれぞれに向けて集中させるように、前記シリンダの内壁に沿って連続的に延在する凸状部」を備えるように構成される。 In another aspect of the structure in which the scraped lubricating oil is concentrated toward each of the first and second end portions, the cylinder inner wall portion may be “from the inner wall of the cylinder toward the inside of the cylinder. A projecting convex portion that extends continuously along the inner wall of the cylinder so as to concentrate the scraped lubricating oil toward the first end and the second end, respectively. It is comprised so that the convex-shaped part which carries out may be provided.
　或いは、前記掻き落とされる潤滑油を前記第１及び前記第２端部のそれぞれに向けて集中させる構造の他の態様において、前記シリンダ内壁部は、「前記シリンダ内壁に設けられた凹状部」であって「前記掻き落とされる潤滑油を前記第１端部及び前記第２端部のそれぞれに向けて集中させるように、前記シリンダの内壁に沿って連続的に延在する凹状部」を備えるように構成される。 Alternatively, in another aspect of the structure in which the scraped lubricating oil is concentrated toward each of the first and second ends, the cylinder inner wall portion is a “concave portion provided on the cylinder inner wall”. And “the concave portion extending continuously along the inner wall of the cylinder so that the lubricant to be scraped off is concentrated toward each of the first end portion and the second end portion”. Configured.
　前記オイルリングにより前記シリンダの内壁から前記クランクケースに向けて掻き落とされる潤滑油は、これらの凸状部又は凹状部に沿って第１及び第２端部に向けて移動し、その後、第１及び第２端部近傍からクランクケース側へと「クランクシャフトジャーナルの取付け部」に沿って移動する。従って、クランクケース内に発生するオイルミスト（オイルの飛沫）の量を低減することができる。 Lubricating oil scraped off from the inner wall of the cylinder toward the crankcase by the oil ring moves toward the first and second ends along these convex portions or concave portions, and then the first And it moves along the “mounting portion of the crankshaft journal” from the vicinity of the second end portion toward the crankcase side. Therefore, the amount of oil mist (oil splash) generated in the crankcase can be reduced.
　一方、前記シリンダ内壁部は、前記第１端部及び前記第２端部のうち前記第１端部のみに向けて前記掻き落とされる潤滑油を集中させる構造を有していてもよい。 On the other hand, the cylinder inner wall portion may have a structure that concentrates the lubricating oil scraped off toward only the first end portion of the first end portion and the second end portion.
　係る内燃機関の一態様において、前記シリンダ内壁部は、前記シリンダの内壁の前記クランクシャフト側の端部（シリンダの内壁の下端部）が「前記掻き落とされる潤滑油を前記第１端部及び前記第２端部のうち前記第１端部のみに向けて集中させる形状」を有するように、構成される。 In one aspect of the internal combustion engine, the inner wall portion of the cylinder has an end portion on the crankshaft side of the inner wall of the cylinder (a lower end portion of the inner wall of the cylinder) that says “the lubricating oil to be scraped off and the first end portion and the It is comprised so that it may have a shape which concentrates toward only the said 1st edge part among 2nd edges.
　これによれば、シリンダの内壁の下端部（例えば、シリンダライナの下端部又はシリンダを構成している機関本体部分の下端部）の形状を変更するだけで、クランクケース内に発生するオイルミストの量を低減することができる。 According to this, the oil mist generated in the crankcase is simply changed by changing the shape of the lower end portion of the inner wall of the cylinder (for example, the lower end portion of the cylinder liner or the lower end portion of the engine main body constituting the cylinder). The amount can be reduced.
　より具体的に述べると、前記シリンダ内壁部は、以下に述べるように構成され得る。
・前記第１端部が、前記クランクシャフトの軸線を含む平面であって前記シリンダの軸線と直交する平面である基準仮想平面から第５距離だけ離間する。
・前記第２端部が、「前記第５距離よりも長い第６距離」だけ前記基準仮想平面から離間する。
・前記シリンダの内壁の前記クランクケース側の端部が、前記第２端部から前記第１端部に近づくにつれて前記基準仮想平面に徐々に近づく形状を有する。 More specifically, the cylinder inner wall can be configured as described below.
The first end portion is separated by a fifth distance from a reference virtual plane that is a plane that includes the axis of the crankshaft and is orthogonal to the axis of the cylinder.
The second end portion is separated from the reference virtual plane by “sixth distance longer than the fifth distance”.
The end portion on the crankcase side of the inner wall of the cylinder has a shape that gradually approaches the reference imaginary plane as it approaches the first end portion from the second end portion.
　この構造によれば、前記オイルリングにより前記シリンダの内壁から前記クランクケースに向けて掻き落とされる潤滑油は、その大部分が前記シリンダの内壁の下端部に沿って第１端部に向けて移動し、その後、第１端部近傍からクランクケース側へと「クランクシャフトジャーナルの取付け部」に沿って移動する。従って、クランクケース内に発生するオイルミスト（オイルの飛沫）の量を低減することができる。 According to this structure, most of the lubricating oil scraped off from the inner wall of the cylinder toward the crankcase by the oil ring moves toward the first end along the lower end of the inner wall of the cylinder. Then, it moves along the “mounting portion of the crankshaft journal” from the vicinity of the first end portion toward the crankcase side. Therefore, the amount of oil mist (oil splash) generated in the crankcase can be reduced.
　前記掻き落とされる潤滑油を前記第１端部及び前記第２端部のうち前記第１端部のみに向けて集中させる構造の他の態様においては、前記シリンダ内壁部が以下に述べる構造を有するように構成される。
・前記シリンダの内壁の前記クランクケース側の端部が、前記クランクシャフトの軸線を含む平面であって前記シリンダの軸線と直交する平面である基準仮想平面と平行である。
・前記シリンダの内壁の前記クランクケース側の端部が、前記第１端部を含む第１領域を除く部分に前記シリンダの内壁から前記シリンダの軸線方向に延びる庇部を備える。 In another aspect of the structure in which the lubricant to be scraped is concentrated toward only the first end portion of the first end portion and the second end portion, the inner wall portion of the cylinder has a structure described below. Configured as follows.
The end of the inner wall of the cylinder on the crankcase side is parallel to a reference virtual plane that is a plane that includes the axis of the crankshaft and is orthogonal to the axis of the cylinder.
The end portion on the crankcase side of the inner wall of the cylinder includes a flange portion extending from the inner wall of the cylinder in the axial direction of the cylinder in a portion excluding the first region including the first end portion.
　この構造によれば、前記オイルリングにより前記シリンダの内壁から前記クランクケースに向けて掻き落とされる潤滑油は、シリンダの内壁の下端部に設けられた庇部に到達し、庇部に沿って第１端部に向けて移動し、その後、第１端部近傍からクランクケース側へと「クランクシャフトジャーナルの取付け部」に沿って移動する。従って、クランクケース内に発生するオイルミスト（オイルの飛沫）の量を低減することができる。 According to this structure, the lubricating oil scraped off from the inner wall of the cylinder toward the crankcase by the oil ring reaches the flange portion provided at the lower end portion of the inner wall of the cylinder, and is changed along the flange portion. It moves toward one end, and then moves along the “crankshaft journal mounting portion” from the vicinity of the first end toward the crankcase. Therefore, the amount of oil mist (oil splash) generated in the crankcase can be reduced.
　前記掻き落とされる潤滑油を前記第１端部及び前記第２端部のうち前記第１端部のみに向けて集中させる構造の他の態様においては、前記シリンダ内壁部は、「前記シリンダの内壁から前記シリンダの内部に向けて突出する凸状部」であって「前記掻き落とされる潤滑油を前記第１端部及び前記第２端部のうち前記第１端部のみに向けて集中させるように前記シリンダの内壁に沿って連続的に延在する凸状部」を備えるように構成される。 In another aspect of the structure in which the lubricant to be scraped is concentrated toward only the first end portion of the first end portion and the second end portion, the inner wall portion of the cylinder is “the inner wall of the cylinder” A convex portion projecting toward the inside of the cylinder ”, and“ the scraped lubricating oil is concentrated toward only the first end portion of the first end portion and the second end portion ”. Are provided with a convex portion extending continuously along the inner wall of the cylinder.
　或いは、前記掻き落とされる潤滑油を前記第１端部及び前記第２端部のうち前記第１端部のみに向けて集中させる構造の他の態様において、前記シリンダ内壁部は、「前記シリンダ内壁に設けられた凹状部」であって「前記掻き落とされる潤滑油を前記第１端部及び前記第２端部のうち前記第１端部のみに向けて集中させるように前記シリンダの内壁に沿って連続的に延在する凹状部」を備えるように構成される。 Alternatively, in another aspect of the structure in which the scraped lubricating oil is concentrated toward only the first end portion of the first end portion and the second end portion, the cylinder inner wall portion may be “the cylinder inner wall portion”. A concave portion provided on the inner wall of the cylinder so that the lubricant to be scraped is concentrated toward only the first end portion of the first end portion and the second end portion. And a concave portion extending continuously.
　前記オイルリングにより前記シリンダの内壁から前記クランクケースに向けて掻き落とされる潤滑油は、これらの凸状部又は凹状部に沿って第１端部に向けて移動し、その後、第１端部近傍からクランクケース側へと「クランクシャフトジャーナルの取付け部」に沿って移動する。従って、クランクケース内に発生するオイルミスト（オイルの飛沫）の量を低減することができる。 The lubricating oil scraped off from the inner wall of the cylinder toward the crankcase by the oil ring moves toward the first end along these convex portions or concave portions, and then the vicinity of the first end portion. Moves along the “crankshaft journal mounting portion” from the crankcase side to the crankcase side. Therefore, the amount of oil mist (oil splash) generated in the crankcase can be reduced.
　これらの内燃機関は、前記吸気通路に設けられたコンプレッサと前記機関の排気通路に設けられたタービンとを含むターボチャージャを備えることができる。この場合、前記ブローバイガス還流装置は前記クランクケース内のブローバイガスを前記機関の吸気通路であって前記コンプレッサの上流へと流入させるように構成され得る。 These internal combustion engines can include a turbocharger including a compressor provided in the intake passage and a turbine provided in the exhaust passage of the engine. In this case, the blow-by gas recirculation device may be configured to flow the blow-by gas in the crankcase into the intake passage of the engine and upstream of the compressor.
　本発明の他の目的、他の特徴及び付随する利点は、以下の図面を参照しつつ記述される本発明の各実施形態についての説明から容易に理解されるであろう。 Other objects, other features, and attendant advantages of the present invention will be easily understood from the description of each embodiment of the present invention described with reference to the following drawings.
図１は、本発明の第１実施形態に係る内燃機関の概略図である。FIG. 1 is a schematic view of an internal combustion engine according to a first embodiment of the present invention. 図２は、図１に示した内燃機関の断面図である。FIG. 2 is a cross-sectional view of the internal combustion engine shown in FIG. 図３は図１に示したシリンダライナを示した図であり、（Ａ）は同シリンダライナを斜め下方から見た斜視図、（Ｂ）は同シリンダライナを反スラスト方向に沿って見た側面図、（Ｃ）は同シリンダライナをクランクシャフトの軸線方向に沿って見た側面図、（Ｄ）は同シリンダライナを同シリンダライナ（シリンダ）の軸線（中心軸線）に沿って見た同シリンダライナの平面図（上面図）である。3A and 3B are views showing the cylinder liner shown in FIG. 1, wherein FIG. 3A is a perspective view of the cylinder liner as viewed obliquely from below, and FIG. 3B is a side view of the cylinder liner as viewed along the anti-thrust direction. (C) is a side view of the cylinder liner as viewed along the axial direction of the crankshaft. (D) is the cylinder as viewed from the cylinder liner (cylinder) along the axis (center axis). It is a top view (top view) of a liner. 図４は、本発明の第１実施形態の変形例に係る内燃機関のカットモデルの斜視図である。FIG. 4 is a perspective view of a cut model of an internal combustion engine according to a modification of the first embodiment of the present invention. 図５は本発明の第２実施形態の内燃機関が有するシリンダライナを示した図であり、（Ａ）は同シリンダライナを「同シリンダライナの軸線及びクランクシャフトの軸線を通る平面」にて切断した断面図（図５（Ｃ）の１－１断面）、（Ｂ）は同シリンダライナを「同シリンダライナの軸線及びスラスト方向を通る平面」にて切断した断面図（図５（Ｃ）の２－２断面）、（Ｃ）は同シリンダライナを同シリンダライナ（シリンダ）の軸線（中心軸線）に沿って見た同シリンダライナの平面図（上面図）である。FIG. 5 is a view showing a cylinder liner included in an internal combustion engine according to a second embodiment of the present invention. FIG. 5A is a view of the cylinder liner cut by “a plane passing through the axis of the cylinder liner and the axis of the crankshaft”. FIG. 5C is a cross-sectional view (cross-section 1-1 of FIG. 5C), and FIG. 5B is a cross-sectional view of the cylinder liner cut along a “plane passing through the axis and thrust direction of the cylinder liner” (FIG. 5C). FIG. 2C is a plan view (top view) of the cylinder liner when the cylinder liner is viewed along the axis (center axis) of the cylinder liner (cylinder). 図６の（Ａ）は本発明の第２実施形態の内燃機関が有するシリンダライナを「同シリンダライナの軸線及びスラスト方向を通る平面」にて切断した断面図（端面図）であり、図６の（Ｂ）は第２実施形態の変形例に係る内燃機関が有するシリンダライナを「同シリンダライナの軸線及びスラスト方向を通る平面」にて切断した断面図（端面図）である。FIG. 6A is a cross-sectional view (end view) of the cylinder liner included in the internal combustion engine of the second embodiment of the present invention cut along a “plane passing through the axis and thrust direction of the cylinder liner”. (B) is a cross-sectional view (end view) of a cylinder liner included in an internal combustion engine according to a modification of the second embodiment, cut along a “plane passing through the axis and thrust direction of the cylinder liner”. 図７は本発明の第３実施形態の内燃機関が有するシリンダライナを「同シリンダライナの軸線及びスラスト方向を通る平面」にて切断した断面図（端面図）である。FIG. 7 is a cross-sectional view (end view) of the cylinder liner included in the internal combustion engine according to the third embodiment of the present invention cut along a “plane passing through the axis and thrust direction of the cylinder liner”. 図８は、本発明の第４実施形態の内燃機関が有するシリンダライナを示した図であり、（Ａ）は同シリンダライナを斜め下方から見た斜視図、（Ｂ）は同シリンダライナを同シリンダライナ（シリンダ）の軸線（中心軸線）に沿って見た同シリンダライナの平面図（上面図）、（Ｃ）は同シリンダライナを図８の（Ｂ）の３－３線に沿った平面にて切断した断面図、（Ｄ）は同シリンダライナを図８の（Ｂ）の４－４線に沿った平面にて切断した断面図である。8A and 8B are views showing a cylinder liner included in an internal combustion engine according to a fourth embodiment of the present invention. FIG. 8A is a perspective view of the cylinder liner as viewed obliquely from below, and FIG. 8B is a view showing the cylinder liner. FIG. 8C is a plan view (top view) of the cylinder liner as viewed along the axis (center axis) of the cylinder liner (cylinder), and FIG. 8C is a plan view of the cylinder liner along line 3-3 in FIG. 8B. FIG. 6D is a cross-sectional view of the cylinder liner cut along a plane along line 4-4 in FIG. 8B. 図９は、本発明の第５実施形態の内燃機関が有するシリンダライナを示した図であり、（Ａ）は同シリンダライナを斜め下方から見た斜視図、（Ｂ）は同シリンダライナを反スラスト方向に沿って見た側面図、（Ｃ）は同シリンダライナをクランクシャフトの軸線方向に沿って見た側面図、（Ｄ）は同シリンダライナを同シリンダライナ（シリンダ）の軸線（中心軸線）に沿って見た同シリンダライナの平面図（上面図）である。9A and 9B are views showing a cylinder liner included in an internal combustion engine according to a fifth embodiment of the present invention. FIG. 9A is a perspective view of the cylinder liner as viewed obliquely from below, and FIG. A side view as viewed along the thrust direction, (C) is a side view of the cylinder liner as viewed along the axial direction of the crankshaft, and (D) is an axis (center axis) of the cylinder liner (cylinder). FIG. 4 is a plan view (top view) of the cylinder liner as viewed along the line (). 図１０は、本発明の第６実施形態の内燃機関が有するシリンダライナを示した図であり、（Ａ）は同シリンダライナを同シリンダライナ（シリンダ）の軸線（中心軸線）に沿って見た同シリンダライナの平面図（上面図）、（Ｂ）は同シリンダライナを図１０の（Ａ）の７－７線に沿った平面にて切断した断面図である。FIG. 10 is a view showing a cylinder liner included in an internal combustion engine according to a sixth embodiment of the present invention. FIG. 10A shows the cylinder liner as viewed along the axis (center axis) of the cylinder liner (cylinder). A plan view (top view) and (B) of the cylinder liner are cross-sectional views of the cylinder liner cut along a plane along line 7-7 in FIG. 10 (A). 図１１は、本発明の第７実施形態の内燃機関が有するシリンダライナを「同シリンダライナの軸線及びスラスト方向を通る平面」にて切断した断面図である。FIG. 11 is a cross-sectional view of a cylinder liner included in an internal combustion engine according to a seventh embodiment of the present invention cut along a “plane passing through the axis and thrust direction of the cylinder liner”. 図１２は、本発明の第８実施形態の内燃機関が有するシリンダライナを示した図であり、（Ａ）は同シリンダライナを斜め下方から見た斜視図、（Ｂ）は同シリンダライナを同シリンダライナ（シリンダ）の軸線（中心軸線）に沿って見た同シリンダライナの平面図（上面図）、（Ｃ）は同シリンダライナを図１２の（Ｂ）の８－８線に沿った平面にて切断した断面図、（Ｄ）は同シリンダライナを図１２の（Ｂ）の９－９線に沿った平面にて切断した断面図である。12A and 12B are views showing a cylinder liner included in an internal combustion engine according to an eighth embodiment of the present invention. FIG. 12A is a perspective view of the cylinder liner as viewed obliquely from below, and FIG. A plan view (top view) of the cylinder liner as viewed along the axis (center axis) of the cylinder liner (cylinder), (C) is a plan view of the cylinder liner along line 8-8 in FIG. 12 (B). (D) is a cross-sectional view of the cylinder liner cut along a plane along line 9-9 in FIG. 12 (B). 図１３は、オイルミスト及びパティキュレートマターの変化の様子を示した概念図である。FIG. 13 is a conceptual diagram showing how oil mist and particulate matter change.
　以下、本発明の各実施形態に係る「ブローバイガス還流装置を備える内燃機関」について図面を参照しながら説明する。各実施形態の内燃機関は、ピストン往復動型・直列・多気筒（４気筒）・ディーゼル機関である。但し、本発明は、ピストン往復動型内燃機関であれば、他の形式の機関にも適用することができる。 Hereinafter, “an internal combustion engine including a blow-by gas recirculation device” according to each embodiment of the present invention will be described with reference to the drawings. The internal combustion engine of each embodiment is a piston reciprocating type, in-line, multi-cylinder (4-cylinder), and diesel engine. However, the present invention can be applied to other types of engines as long as they are piston reciprocating internal combustion engines.
＜第１実施形態＞
（概略構成）
　図１に示したように、内燃機関１０は、機関本体部２０、吸気通路部３０、排気通路部４０及びブローバイガス還流装置５０を備えている。 <First Embodiment>
(Outline configuration)
As shown in FIG. 1, the internal combustion engine 10 includes an engine body portion 20, an intake passage portion 30, an exhaust passage portion 40, and a blow-by gas recirculation device 50.
　機関本体部２０は、クランクケース２１、オイルパン２２、シリンダブロック２３及びシリンダヘッド部２４を含んでいる。 The engine body 20 includes a crankcase 21, an oil pan 22, a cylinder block 23, and a cylinder head 24.
　クランクケース２１は、クランクシャフト２１ａを回転可能に支持している。
　オイルパン２２は、クランクケース２１の下方においてクランクケース２１に固定されている。オイルパン２２は、クランクケース２１とともに、クランクシャフト２１ａ及び潤滑油ＯＬを収容する空間（以下、「クランクケース室」とも称呼する。）を形成している。 The crankcase 21 rotatably supports the crankshaft 21a.
The oil pan 22 is fixed to the crankcase 21 below the crankcase 21. The oil pan 22, together with the crankcase 21, forms a space for accommodating the crankshaft 21 a and the lubricating oil OL (hereinafter also referred to as “crankcase chamber”).
　シリンダブロック２３は、クランクケース２１の上方においてクランクケース２１に固定されている。シリンダブロック２３は、アルミニウム製であって、中空円筒状のシリンダ（シリンダボア）２３ａを複数個（４気筒分）備えている。シリンダ２３ａの内周には鋳鉄製のシリンダライナ２３ｂが嵌入されている。従って、シリンダライナ２３ｂは「シリンダ２３ａの内壁を構成するシリンダ内壁部」である。 The cylinder block 23 is fixed to the crankcase 21 above the crankcase 21. The cylinder block 23 is made of aluminum and includes a plurality of hollow cylinders (cylinder bores) 23a (for four cylinders). A cast iron cylinder liner 23b is fitted into the inner periphery of the cylinder 23a. Therefore, the cylinder liner 23b is “a cylinder inner wall portion constituting the inner wall of the cylinder 23a”.
　シリンダ２３ａにはピストン２３ｃが収容されている。
　ピストン２３ｃは略円筒形であり、側面に複数のピストンリングを備えている。複数のピストンリングのうちの最も下方（クランクケース２１側）のリングは、所謂「オイルリングＯＲ」である。オイルリングＯＲは、シリンダ２３ａの内壁（即ち、シリンダライナ２３ｂの内周壁）を摺動しながら同内壁の潤滑油（油膜）をクランクケース２１側に掻き落とすようになっている。ピストン２３ｃは、コネクティングロッド２３ｄによってクランクシャフト２１ａに連結されている。ピストン２３ｃの上面（頂面）はシリンダライナ２３ｂの内壁面及びシリンダヘッド部２４の下面と共に燃焼室ＣＣを形成している。 A piston 23c is accommodated in the cylinder 23a.
The piston 23c is substantially cylindrical and includes a plurality of piston rings on the side surface. The lowermost ring (crankcase 21 side) of the plurality of piston rings is a so-called “oil ring OR”. The oil ring OR scrapes the lubricating oil (oil film) on the inner wall of the cylinder 23a toward the crankcase 21 while sliding on the inner wall of the cylinder 23a (that is, the inner peripheral wall of the cylinder liner 23b). The piston 23c is connected to the crankshaft 21a by a connecting rod 23d. The upper surface (top surface) of the piston 23 c forms a combustion chamber CC together with the inner wall surface of the cylinder liner 23 b and the lower surface of the cylinder head portion 24.
　シリンダヘッド部２４は、シリンダブロック２３の上方においてシリンダブロック２３に固定されている。シリンダヘッド部２４には、燃焼室ＣＣに連通する吸気ポート、及び、燃焼室ＣＣに連通する排気ポートが形成されている。吸気ポートは吸気弁により開閉される。吸気弁は、シリンダヘッド部２４に収容された「図示しないインテークカムシャフトのカム」により駆動される。排気ポートは排気弁により開閉される。排気弁は、シリンダヘッド部２４に収容された「図示しないエグゾーストカムシャフトのカム」により駆動される。シリンダヘッド部２４は、シリンダヘッドカバー２４ａにより覆われている。更に、シリンダヘッド部２４内には図示しない燃料噴射弁が備えられている。 The cylinder head portion 24 is fixed to the cylinder block 23 above the cylinder block 23. The cylinder head portion 24 is formed with an intake port communicating with the combustion chamber CC and an exhaust port communicating with the combustion chamber CC. The intake port is opened and closed by an intake valve. The intake valve is driven by “a cam of an intake cam shaft (not shown)” accommodated in the cylinder head portion 24. The exhaust port is opened and closed by an exhaust valve. The exhaust valve is driven by “a cam of an exhaust cam shaft (not shown)” accommodated in the cylinder head portion 24. The cylinder head portion 24 is covered with a cylinder head cover 24a. Further, a fuel injection valve (not shown) is provided in the cylinder head portion 24.
　吸気通路部３０は、吸気管３１、インタークーラー３２及びターボチャージャ６０のコンプレッサ６１を含んでいる。吸気管３１は吸気ポートと接続されている。従って、吸気管３１及び吸気ポートは吸気通路を構成している。 The intake passage 30 includes an intake pipe 31, an intercooler 32, and a compressor 61 of a turbocharger 60. The intake pipe 31 is connected to the intake port. Therefore, the intake pipe 31 and the intake port constitute an intake passage.
　コンプレッサ６１は吸気管３１に介装されていて、吸入空気を圧縮するようになっている。インタークーラー３２は、吸気管３１であってコンプレッサ６１よりも下流の位置に介装されていて、吸入空気を冷却するようになっている。 The compressor 61 is interposed in the intake pipe 31 and compresses intake air. The intercooler 32 is interposed in the intake pipe 31 at a position downstream of the compressor 61, and cools intake air.
　排気通路部４０は、排気管４１及びターボチャージャ６０のタービン６２を含んでいる。排気管４１は排気ポートと接続されている。従って、排気管４１及び排気ポートは排気通路を構成している。 The exhaust passage section 40 includes an exhaust pipe 41 and a turbine 62 of the turbocharger 60. The exhaust pipe 41 is connected to the exhaust port. Therefore, the exhaust pipe 41 and the exhaust port constitute an exhaust passage.
　タービン６２は排気管４１に介装されていて、排ガスにより回転されるようになっている。この結果、タービン６２に連結されたコンプレッサ６１が回転し、それによりターボチャージャ６０は過給を行なうようになっている。 The turbine 62 is interposed in the exhaust pipe 41 and is rotated by exhaust gas. As a result, the compressor 61 connected to the turbine 62 rotates, whereby the turbocharger 60 performs supercharging.
　ブローバイガス還流装置５０は、第１ガス通路部５１と、第２ガス通路部５２と、第３ガス通路部５３と、を含む。 The blow-by gas recirculation device 50 includes a first gas passage portion 51, a second gas passage portion 52, and a third gas passage portion 53.
　第１ガス通路部５１はシリンダブロック２３内に形成されている。第１ガス通路部５１はクランクケース室をシリンダヘッド部２４内の第２ガス通路部５２に接続するようになっている。第２ガス通路部５２は、シリンダヘッド部２４内の所定の経路を通り、第３ガス通路部５３の一端に接続されている。第３ガス通路部５３は機関１０の外部に設けられたガス管により構成されている。第３ガス通路部５３の他端は吸気管３１であってコンプレッサ６１よりも上流位置に接続されている。 The first gas passage portion 51 is formed in the cylinder block 23. The first gas passage portion 51 connects the crankcase chamber to the second gas passage portion 52 in the cylinder head portion 24. The second gas passage portion 52 passes through a predetermined path in the cylinder head portion 24 and is connected to one end of the third gas passage portion 53. The third gas passage portion 53 is constituted by a gas pipe provided outside the engine 10. The other end of the third gas passage portion 53 is the intake pipe 31 and is connected to a position upstream of the compressor 61.
　従って、燃焼室ＣＣからクランクケース室に漏出したブローバイガスは、第１ガス通路部５１、第２ガス通路部５２及び第３ガス通路部５３を通って吸気通路部３０へと還流（流入）させられる。なお、第３ガス通路部５３には図示しない周知のＰＣＶバルブが備えられてもよい。 Accordingly, the blow-by gas leaked from the combustion chamber CC into the crankcase chamber is recirculated (inflowed) to the intake passage portion 30 through the first gas passage portion 51, the second gas passage portion 52, and the third gas passage portion 53. It is done. The third gas passage portion 53 may be provided with a well-known PCV valve (not shown).
　図２は機関１０の詳細な断面図である。図２に示したように、クランクシャフト２１ａは、クランクジャーナル２１１、クランクピン２１２、クランクアーム２１３及びバランスウエイト２１４を含んでいる。クランクピン２１２はコネクティングロッド２３ｄと回転自在に連結されている。クランクアーム２１３は、クランクジャーナル２１１とクランクピン２１２とを連結している。クランクアーム２１３は、バランスウエイト２１４と連結されている。 FIG. 2 is a detailed sectional view of the engine 10. As shown in FIG. 2, the crankshaft 21 a includes a crank journal 211, a crankpin 212, a crank arm 213, and a balance weight 214. The crank pin 212 is rotatably connected to the connecting rod 23d. The crank arm 213 connects the crank journal 211 and the crank pin 212. The crank arm 213 is connected to the balance weight 214.
　クランクケース２１は、シリンダ２３ａのクランクシャフト２１ａの軸線方向における端部からオイルパン２２に向けて延設された縦壁部（板状のクランクジャーナル取付け部）２１ｂと、その縦壁部の下端面にボルト固定されるクランクキャップ２１ｃと、を含んでいる。従って、縦壁部２１ｂは、ピストン２３ｃのスラスト方向（及び反スラスト方向）と平行な縦壁（縦壁面）を構成している。更に、縦壁部２１ｂとクランクキャップ２１ｃとにより構成される軸受け部にクランクジャーナル２１１がベアリングを介して回転自在に保持されている。なお、係るスラスト方向及び反スラスト方向の定義は、内燃機関の分野において周知であるスラスト方向及び反スラスト方向の定義とそれぞれ同一である。 The crankcase 21 includes a vertical wall portion (plate-shaped crank journal mounting portion) 21b extending from an end portion of the cylinder 23a in the axial direction of the crankshaft 21a toward the oil pan 22, and a lower end surface of the vertical wall portion. And a crank cap 21c fixed to a bolt. Therefore, the vertical wall portion 21b forms a vertical wall (vertical wall surface) parallel to the thrust direction (and anti-thrust direction) of the piston 23c. Further, a crank journal 211 is rotatably held via a bearing at a bearing portion constituted by the vertical wall portion 21b and the crank cap 21c. The definitions of the thrust direction and the anti-thrust direction are the same as the definitions of the thrust direction and the anti-thrust direction that are well known in the field of internal combustion engines.
　ところで、従来の内燃機関が有するシリンダライナは円筒形（上面及び下面が開放した中空円筒形）である。従って、従来のシリンダライナの下端部（シリンダライナのクランクケース側の端部）は平坦であって、クランクシャフトの軸線と平行である。 Incidentally, the cylinder liner of the conventional internal combustion engine has a cylindrical shape (a hollow cylindrical shape with the upper and lower surfaces open). Therefore, the lower end of the conventional cylinder liner (the end of the cylinder liner on the crankcase side) is flat and parallel to the axis of the crankshaft.
　これに対し、機関１０のシリンダライナ２３ｂは、図１乃至図３（特に、図３）に示したように、ピストン２３ｃの可動領域よりも下方（クランクケース２１側）において、「クランクケース室にオイルミストを発生させないように工夫された特殊な形状」を有する。 On the other hand, as shown in FIGS. 1 to 3 (particularly, FIG. 3), the cylinder liner 23b of the engine 10 is located below the movable region of the piston 23c (on the crankcase 21 side). It has a special shape devised so as not to generate oil mist.
　即ち、シリンダライナ２３ｂは、シリンダライナ２３ｂのクランクケース２１側の端部２３ｂ１の部分であって、図３の（Ｄ）に示したようにシリンダライナ２３ｂをシリンダ２３ａの中心軸線（従って、シリンダライナ２３ｂの中心軸線ＣＬ）に沿って見た場合にクランクシャフト２１ａの軸線ＳＣと重なる一対の部分である「第１端部Ａ１及び第２端部Ａ２」のそれぞれに向けて（即ち、第１端部Ａ１及び第２端部Ａ２の双方に向けて）、オイルリングＯＲによりシリンダライナ２３ｂの内壁からクランクケース２１に向けて掻き落とされる潤滑油を「集中」させる構造（潤滑油誘導構造）を有している。なお、シリンダライナ２３ｂのクランクケース２１側の端部２３ｂ１は、シリンダヘッド部２４と反対側のシリンダライナ２３ｂの端部２３ｂ１であって、以下において「シリンダライナ２３ｂの下端部２３ｂ１」とも称呼される。この称呼方法は他の実施形態においても同様に使用される。 That is, the cylinder liner 23b is a portion of the end 23b1 on the crankcase 21 side of the cylinder liner 23b. As shown in FIG. 3D, the cylinder liner 23b is connected to the center axis of the cylinder 23a (accordingly, the cylinder liner 23b). 23b toward the first end A1 and the second end A2 that are a pair of portions overlapping the axis SC of the crankshaft 21a when viewed along the center axis CL) (ie, the first end A2). (Toward both the part A1 and the second end part A2), the oil ring OR has a structure (lubricating oil guiding structure) for “concentrating” the lubricating oil scraped off from the inner wall of the cylinder liner 23b toward the crankcase 21. is doing. The end 23b1 of the cylinder liner 23b on the crankcase 21 side is the end 23b1 of the cylinder liner 23b opposite to the cylinder head 24, and is hereinafter also referred to as “the lower end 23b1 of the cylinder liner 23b”. . This naming method is used in other embodiments as well.
　この第１端部Ａ１は、シリンダライナ２３ｂの下端部２３ｂ１であって、クランクシャフト２１ａの軸線ＳＣ方向に位置する一対の部位のうちの一つ部位である。更に、第２端部Ａ２は、シリンダライナ２３ｂの下端部２３ｂ１であって、クランクシャフト２１ａの軸線ＳＣ方向に位置する一対の部位のうちの他の一つ部位である。 The first end A1 is a lower end 23b1 of the cylinder liner 23b and is one part of a pair of parts located in the direction of the axis SC of the crankshaft 21a. Further, the second end portion A2 is the lower end portion 23b1 of the cylinder liner 23b and is another one portion of the pair of portions located in the axis SC direction of the crankshaft 21a.
　ここで、図３の（Ｂ）及び（Ｃ）等に示した基準仮想平面ＶＰを、クランクシャフト２１ａの軸線ＳＣを含む平面であってシリンダ２３ａの軸線ＣＬと直交する平面と定義する。この定義は他の実施形態にも適用される。この場合、ピストン２３ｃのスラスト方向は基準仮想平面ＶＰと平行であってクランクシャフト２１ａの軸線ＳＣ方向と直交する方向となる。ピストン２３ｃの反スラスト方向はスラスト方向の反対向きである。以下、これらの定義に従って、シリンダライナ２３ｂの下端部２３ｂ１の形状について記述する。 Here, the reference virtual plane VP shown in (B) and (C) of FIG. 3 is defined as a plane including the axis SC of the crankshaft 21a and orthogonal to the axis CL of the cylinder 23a. This definition also applies to other embodiments. In this case, the thrust direction of the piston 23c is parallel to the reference virtual plane VP and is orthogonal to the axis SC direction of the crankshaft 21a. The anti-thrust direction of the piston 23c is opposite to the thrust direction. Hereinafter, the shape of the lower end portion 23b1 of the cylinder liner 23b will be described in accordance with these definitions.
　第１端部Ａ１は、基準仮想平面ＶＰから第１距離Ｌ１だけ離間している。
　第２端部Ａ２は、基準仮想平面ＶＰから第２距離Ｌ２だけ離間している。
　シリンダライナ２３ｂの下端部２３ｂ１の部分であってピストン２３ｃのスラスト方向に位置する部分であるスラスト方向部Ａ３は、基準仮想平面ＶＰから第３距離Ｌ３だけ離間している。
　シリンダライナ２３ｂの下端部２３ｂ１の部分であってピストン２３ｃの反スラスト方向に位置する部分である反スラスト方向部Ａ４は、基準仮想平面ＶＰから第４距離Ｌ４だけ離間している。 The first end A1 is separated from the reference virtual plane VP by a first distance L1.
The second end A2 is separated from the reference virtual plane VP by the second distance L2.
A thrust direction portion A3, which is a portion of the lower end portion 23b1 of the cylinder liner 23b and is located in the thrust direction of the piston 23c, is separated from the reference virtual plane VP by a third distance L3.
An anti-thrust direction portion A4 that is a portion of the lower end portion 23b1 of the cylinder liner 23b and is located in the anti-thrust direction of the piston 23c is separated from the reference virtual plane VP by a fourth distance L4.
　第１距離Ｌ１は、第３距離Ｌ３及び第４距離Ｌ４の何れよりも短い。
　第２距離Ｌ２は、第３距離Ｌ３及び第４距離Ｌ４の何れよりも短い。
　第１距離Ｌ１は第２距離Ｌ２と等しくてもよく、相違していてもよい。
　第３距離Ｌ３は第４距離Ｌ４と等しくてもよく、相違していてもよい。 The first distance L1 is shorter than both the third distance L3 and the fourth distance L4.
The second distance L2 is shorter than both the third distance L3 and the fourth distance L4.
The first distance L1 may be equal to or different from the second distance L2.
The third distance L3 may be equal to or different from the fourth distance L4.
　第１端部Ａ１とスラスト方向部Ａ３との間のシリンダライナ２３ｂの下端部２３ｂ１は、スラスト方向部Ａ３から第１端部Ａ１に近づくにつれて基準仮想平面ＶＰに徐々に近づく。換言すると、「第１端部Ａ１とスラスト方向部Ａ３との間のシリンダライナ２３ｂの下端部２３ｂ１」はスラスト方向に沿ってシリンダライナ２３ｂを見た場合（図３の（Ｂ））において滑らかな曲線状であり、「第１端部Ａ１とスラスト方向部Ａ３との間のシリンダライナ２３ｂの下端部２３ｂ１」と「基準仮想平面ＶＰ」との距離はスラスト方向部Ａ３から第１端部Ａ１に近づくにつれて単調減少する。なお、「単調減少」は数学分野で用いられる「単調に減少すること」と同義である。 The lower end portion 23b1 of the cylinder liner 23b between the first end portion A1 and the thrust direction portion A3 gradually approaches the reference virtual plane VP as it approaches the first end portion A1 from the thrust direction portion A3. In other words, “the lower end portion 23b1 of the cylinder liner 23b between the first end portion A1 and the thrust direction portion A3” is smooth when the cylinder liner 23b is viewed along the thrust direction (FIG. 3B). The distance between the “lower end 23b1 of the cylinder liner 23b between the first end A1 and the thrust direction part A3” and the “reference virtual plane VP” is from the thrust direction part A3 to the first end A1. It decreases monotonously as it gets closer. Note that “monotonically decreasing” is synonymous with “monotonically decreasing” used in the mathematical field.
　第２端部Ａ２とスラスト方向部Ａ３との間のシリンダライナ２３ｂの下端部２３ｂ１は、スラスト方向部Ａ３から第２端部Ａ２に近づくにつれて基準仮想平面ＶＰに徐々に近づく。換言すると、「第２端部Ａ２とスラスト方向部Ａ３との間のシリンダライナ２３ｂの下端部２３ｂ１」はスラスト方向に沿ってシリンダライナ２３ｂを見た場合（図３の（Ｂ））において滑らかな曲線状であり、「第２端部Ａ２とスラスト方向部Ａ３との間のシリンダライナ２３ｂの下端部２３ｂ１」と「基準仮想平面ＶＰ」との距離はスラスト方向部Ａ３から第２端部Ａ２に近づくにつれて単調減少する。 The lower end portion 23b1 of the cylinder liner 23b between the second end portion A2 and the thrust direction portion A3 gradually approaches the reference virtual plane VP as it approaches the second end portion A2 from the thrust direction portion A3. In other words, “the lower end portion 23b1 of the cylinder liner 23b between the second end portion A2 and the thrust direction portion A3” is smooth when the cylinder liner 23b is viewed along the thrust direction (FIG. 3B). The distance between the “lower end portion 23b1 of the cylinder liner 23b between the second end portion A2 and the thrust direction portion A3” and the “reference virtual plane VP” is from the thrust direction portion A3 to the second end portion A2. It decreases monotonously as it gets closer.
　第１端部Ａ１と反スラスト方向部Ａ４との間のシリンダライナ２３ｂの下端部２３ｂ１は、反スラスト方向部Ａ４から第１端部Ａ１に近づくにつれて基準仮想平面ＶＰに徐々に近づく。換言すると、「第１端部Ａ１と反スラスト方向部Ａ４との間のシリンダライナ２３ｂの下端部２３ｂ１」は反スラスト方向（又はスラスト方向）に沿ってシリンダライナ２３ｂを見た場合（図３の（Ｂ））において滑らかな曲線状であり、「第１端部Ａ１と反スラスト方向部Ａ４との間のシリンダライナ２３ｂの下端部２３ｂ１」と「基準仮想平面ＶＰ」との距離は反スラスト方向部Ａ４から第１端部Ａ１に近づくにつれて単調減少する。 The lower end portion 23b1 of the cylinder liner 23b between the first end portion A1 and the anti-thrust direction portion A4 gradually approaches the reference virtual plane VP as it approaches the first end portion A1 from the anti-thrust direction portion A4. In other words, “the lower end portion 23b1 of the cylinder liner 23b between the first end portion A1 and the anti-thrust direction portion A4” when the cylinder liner 23b is viewed along the anti-thrust direction (or the thrust direction) (see FIG. 3). (B)), the distance between the “lower end 23b1 of the cylinder liner 23b between the first end A1 and the anti-thrust direction portion A4” and the “reference virtual plane VP” is the anti-thrust direction. It decreases monotonously as it approaches the first end A1 from the part A4.
　第２端部Ａ２と反スラスト方向部Ａ４との間のシリンダライナ２３ｂの下端部２３ｂ１は、反スラスト方向部Ａ４から第２端部Ａ２に近づくにつれて基準仮想平面ＶＰに徐々に近づく。換言すると、「第２端部Ａ２と反スラスト方向部Ａ４との間のシリンダライナ２３ｂの下端部２３ｂ１」は、反スラスト方向（又はスラスト方向）に沿ってシリンダライナ２３ｂを見た場合（図３の（Ｂ））において滑らかな曲線状であり、「第２端部Ａ２と反スラスト方向部Ａ４との間のシリンダライナ２３ｂの下端部２３ｂ１」と「基準仮想平面ＶＰ」との距離は反スラスト方向部Ａ４から第２端部Ａ２に近づくにつれて単調減少する。 The lower end portion 23b1 of the cylinder liner 23b between the second end portion A2 and the anti-thrust direction portion A4 gradually approaches the reference virtual plane VP as it approaches the second end portion A2 from the anti-thrust direction portion A4. In other words, “the lower end portion 23b1 of the cylinder liner 23b between the second end portion A2 and the anti-thrust direction portion A4” when the cylinder liner 23b is viewed along the anti-thrust direction (or the thrust direction) (FIG. 3). (B)), the distance between the “lower end 23b1 of the cylinder liner 23b between the second end A2 and the anti-thrust direction portion A4” and the “reference virtual plane VP” is the anti-thrust. It decreases monotonously as it approaches the second end A2 from the direction part A4.
　このように構成された内燃機関１０によれば、オイルリングＯＲによりシリンダ２３ａの内壁（即ち、シリンダライナ２３ｂの内壁）からクランクケース２１（及びオイルパン２２）に向けて掻き落とされる潤滑油は（潤滑油の粘性及び表面張力等により）、第１端部Ａ１及び第２端部Ａ２に向けて集中する（図１乃至図３の各図における破線の矢印を参照。）。 According to the internal combustion engine 10 configured as described above, the lubricating oil scraped off from the inner wall of the cylinder 23a (that is, the inner wall of the cylinder liner 23b) toward the crankcase 21 (and the oil pan 22) by the oil ring OR is ( It concentrates toward the first end A1 and the second end A2 (see the broken arrows in each of FIGS. 1 to 3) due to the viscosity and surface tension of the lubricating oil.
　従って、シリンダ２３ａの内壁（即ち、シリンダライナ２３ｂの内壁）からクランクケース２１（及びオイルパン２２）に向けて掻き落とされる潤滑油は、縦壁部（クランクジャーナル取付け部）２１ｂの表面に沿って滑落するので、高速で回転・運動している部材（クランクピン２１２、クランクアーム２１３、バランスウエイト２１４及びコネクティングロッド２３ｄ等）に「落下しながら衝突して飛散する」ことがない。よって、クランクケース室において発生するオイルミスト（潤滑油の飛沫）の量を低減することができる。その結果、ブローバイガス還流装置５０によって吸気通路部３０を構成する部材（特に、コンプレッサ６１）に流入する「煤等のパティキュレートマターを取り込んだオイルミストＯＭ」の量を低減することができる。従って、吸気通路部３０を構成する部材へのデポジットの堆積量を低減することができる。 Accordingly, the lubricating oil scraped off from the inner wall of the cylinder 23a (that is, the inner wall of the cylinder liner 23b) toward the crankcase 21 (and the oil pan 22) is along the surface of the vertical wall portion (crank journal mounting portion) 21b. Since it slides down, it does not “collision and scatter while falling” on members (crank pin 212, crank arm 213, balance weight 214, connecting rod 23d, etc.) that rotate and move at high speed. Therefore, it is possible to reduce the amount of oil mist (lubricant splash) generated in the crankcase chamber. As a result, it is possible to reduce the amount of “oil mist OM incorporating particulate matter such as soot” that flows into the members (particularly the compressor 61) constituting the intake passage portion 30 by the blow-by gas recirculation device 50. Accordingly, it is possible to reduce the amount of deposit accumulated on the members constituting the intake passage portion 30.
＜第１実施形態の変形例＞
　本発明の第１実施形態の変形例は、内燃機関がシリンダライナ２３ｂを備えない機関である場合において、シリンダライナ２３ｂに代えて、シリンダブロック２３が形成するシリンダ２３ａ（シリンダボア）の下端部（クランクケース２１側の端部）が、第１実施形態のシリンダライナ２３ｂと同様の形状を有している点のみにおいて、第１実施形態と相違している。 <Modification of First Embodiment>
In a modification of the first embodiment of the present invention, when the internal combustion engine is an engine that does not include the cylinder liner 23b, the lower end (crank) of the cylinder 23a (cylinder bore) formed by the cylinder block 23 is used instead of the cylinder liner 23b. The case 21 is different from the first embodiment only in that the end portion on the case 21 side has the same shape as the cylinder liner 23b of the first embodiment.
　即ち、第１実施形態の変形例においては、シリンダ２３ａが「クランクケース室にオイルミストを発生させないように工夫された特殊な形状」を有する。換言すると、シリンダ２３ａは、図４に示したように、シリンダ２３ａの下端部（即ち、シリンダ２３ａのクランクケース側の端部）の部分であって、シリンダ２３ａをシリンダの軸線ＣＬに沿って見た場合にクランクシャフト２１ａの軸線と重なる一対の部分である「第１端部及び第２端部」のそれぞれに向けて、オイルリングによりシリンダ２３ａの内壁からクランクケース２１に向けて掻き落とされる潤滑油を集中させる構造を有している。 That is, in the modification of the first embodiment, the cylinder 23a has “a special shape devised so as not to generate oil mist in the crankcase chamber”. In other words, as shown in FIG. 4, the cylinder 23a is a portion of the lower end portion of the cylinder 23a (that is, the end portion on the crankcase side of the cylinder 23a), and the cylinder 23a is viewed along the cylinder axis CL. In this case, lubrication is scraped off from the inner wall of the cylinder 23a toward the crankcase 21 by the oil ring toward each of the "first end portion and second end portion" which are a pair of portions overlapping the axis of the crankshaft 21a. It has a structure that concentrates oil.
　従って、シリンダ２３ａの内壁からクランクケース２１（及びオイルパン２２）に向けて掻き落とされる潤滑油は、縦壁部（クランクジャーナル取付け部）２１ｂに沿って滑落するので、高速で回転・運動している部材に「落下しながら衝突して飛散する」ことがない。よって、クランクケース室内のオイルミストの量を低減することができるので、煤等のパティキュレートマターを取り込んだオイルミストＯＭの量を低減することができる。従って、吸気通路部３０を構成する部材へのデポジットの堆積量を低減することができる。 Accordingly, the lubricating oil scraped off from the inner wall of the cylinder 23a toward the crankcase 21 (and the oil pan 22) slides along the vertical wall portion (crank journal mounting portion) 21b, so that it rotates and moves at high speed. There is no “clashing and scattering while falling”. Therefore, since the amount of oil mist in the crankcase chamber can be reduced, the amount of oil mist OM incorporating particulate matter such as soot can be reduced. Accordingly, it is possible to reduce the amount of deposit accumulated on the members constituting the intake passage portion 30.
＜第２実施形態＞
　本発明の第２実施形態に係る内燃機関は、図５に示したように、内燃機関１０のシリンダライナ２３ｂに置換されるシリンダライナ１２３ｂの形状がシリンダライナ２３ｂの形状と相違する点においてのみ内燃機関１０と相違している。従って、以下、この相違点を中心として説明する。 Second Embodiment
As shown in FIG. 5, the internal combustion engine according to the second embodiment of the present invention is an internal combustion engine only in that the shape of the cylinder liner 123 b replaced with the cylinder liner 23 b of the internal combustion engine 10 is different from the shape of the cylinder liner 23 b. It is different from the engine 10. Therefore, hereinafter, this difference will be mainly described.
　このシリンダライナ１２３ｂは、従来のシリンダライナと同様に円筒形（上面及び下面が開放した中空円筒形）である。従って、シリンダライナ１２３ｂの下端部（シリンダライナ１２３ｂのクランクケース２１側の端部）１２３ｂ１は平坦であって、基準仮想平面ＶＰと平行である。 This cylinder liner 123b has a cylindrical shape (a hollow cylindrical shape with an open upper surface and a lower surface), similar to a conventional cylinder liner. Therefore, the lower end portion (end portion of the cylinder liner 123b on the crankcase 21 side) 123b1 of the cylinder liner 123b is flat and parallel to the reference virtual plane VP.
　但し、シリンダライナ１２３ｂは、その内壁（内周壁）にシリンダライナ１２３ｂの内方に突出した凸状部（「***部、突出部、尾根部又は潤滑油誘導路形成部」とも言うことができる。）１２３ｂ２を備えている。この凸状部１２３ｂ２の軸線は、シリンダライナ２３ｂの下端部２３ｂ１が描く線と略同一である。従って、凸状部１２３ｂ２は、ピストン２３ｃの可動領域よりも下方（クランクケース２１側）に設けられている。更に、凸状部１２３ｂ２は、高速で回転・運動している部材（クランクピン２１２、クランクアーム２１３、バランスウエイト２１４及びコネクティングロッド２３ｄ等）の運動を阻害しない高さ（シリンダライナ１２３ｂの径方向長さ）を有している。 However, the cylinder liner 123b can also be referred to as a convex portion (an “uplift portion, a protruding portion, a ridge portion, or a lubricating oil guide path forming portion”) that protrudes inward of the cylinder liner 123b on its inner wall (inner peripheral wall). ) 123b2. The axis of the convex portion 123b2 is substantially the same as the line drawn by the lower end portion 23b1 of the cylinder liner 23b. Accordingly, the convex portion 123b2 is provided below (on the crankcase 21 side) the movable region of the piston 23c. Further, the convex portion 123b2 has a height (the length in the radial direction of the cylinder liner 123b) that does not hinder the movement of members (crank pin 212, crank arm 213, balance weight 214, connecting rod 23d, etc.) that rotate and move at high speed. A).
　即ち、凸状部１２３ｂ２は、図５の（Ｃ）に示したように、シリンダライナ１２３ｂをシリンダの中心軸線（従って、シリンダライナ１２３ｂの中心軸線ＣＬ１）に沿って見た場合にクランクシャフト２１ａの軸線ＳＣと重なる一対の部分である「第１端部Ｂ１及び第２端部Ｂ２」のそれぞれへ（即ち、第１端部Ｂ１及び第２端部Ｂ２の双方へ）、オイルリングＯＲによりシリンダライナ１２３ｂの内壁からクランクケース２１に向けて掻き落とされる潤滑油を集中させる構造・形状（潤滑油誘導構造）を有するように延在している。 That is, as shown in FIG. 5C, the convex portion 123b2 is formed on the crankshaft 21a when the cylinder liner 123b is viewed along the center axis of the cylinder (accordingly, the center axis CL1 of the cylinder liner 123b). A cylinder liner is connected to each of the “first end B1 and second end B2” (that is, to both the first end B1 and the second end B2) which are a pair of portions overlapping the axis SC by an oil ring OR. It extends so as to have a structure / shape (lubricating oil guiding structure) for concentrating lubricating oil scraped off from the inner wall of 123b toward the crankcase 21.
　凸状部１２３ｂ２の軸線に直交する断面の形状は、図６（Ａ）に示したような略長方形である。凸状部１２３ｂ２の「シリンダライナ１２３ｂの中心軸線ＣＬ１に沿う方向」の長さは一定「Ｈ」である。凸状部１２３ｂ２の「シリンダライナ１２３ｂの中心軸線ＣＬ１に向かう方向」の長さは一定「Ｌ」である。なお、図６（Ｂ）に示したように、凸状部１２３ｂ２の軸線に直交する断面の形状は、シリンダライナ１２３ｂの中心軸線ＣＬ１方向へ延びる底部Ｔ１と、その底部Ｔ１の端部からシリンダライナ１２３ｂの上端（シリンダヘッド側）に向けて斜めに屈曲した斜面部Ｔ２と、を有していてもよい。 The shape of the cross section perpendicular to the axis of the convex portion 123b2 is a substantially rectangular shape as shown in FIG. The length of the convex portion 123b2 in the “direction along the central axis CL1 of the cylinder liner 123b” is constant “H”. The length of the convex portion 123b2 in the “direction toward the central axis CL1 of the cylinder liner 123b” is constant “L”. As shown in FIG. 6B, the shape of the cross section orthogonal to the axis of the convex portion 123b2 is that the bottom portion T1 extends in the direction of the central axis CL1 of the cylinder liner 123b, and the cylinder liner extends from the end of the bottom portion T1. It may have a slope portion T2 that is bent obliquely toward the upper end (cylinder head side) of 123b.
　図５を参照しながら凸状部１２３ｂ２の形状について、より具体的に説明する。第１端部Ｂ１は、シリンダライナ１２３ｂの下端部１２３ｂ１であって、クランクシャフト２１ａの軸線ＳＣ方向に位置する一対の部位のうちの一つ部位である。更に、第２端部Ｂ２は、シリンダライナ１２３ｂの下端部１２３ｂ１であって、クランクシャフト２１ａの軸線ＳＣ方向に位置する一対の部位のうちの他の一つ部位である。 The shape of the convex portion 123b2 will be described more specifically with reference to FIG. The first end B1 is a lower end 123b1 of the cylinder liner 123b and is one part of a pair of parts located in the axis SC direction of the crankshaft 21a. Furthermore, the second end B2 is the lower end 123b1 of the cylinder liner 123b, and is another part of the pair of parts located in the direction of the axis SC of the crankshaft 21a.
　凸状部１２３ｂ２は、図５の（Ｃ）から理解されるように、第１端部Ｂ１を含む所定領域及び第２端部Ｂ２を含む所定領域を除く部分に設けられている。凸状部１２３ｂ２は、シリンダライナ１２３ｂの軸線ＣＬ１及びクランクシャフト２１ａの軸線ＳＣを含む平面に関して対称である。従って、以下、シリンダライナ１２３ｂの反スラスト方向側に設けられている凸状部１２３ｂ２の形状について説明する。 As can be understood from FIG. 5C, the convex portion 123b2 is provided in a portion excluding the predetermined region including the first end B1 and the predetermined region including the second end B2. The convex portion 123b2 is symmetric with respect to a plane including the axis CL1 of the cylinder liner 123b and the axis SC of the crankshaft 21a. Accordingly, hereinafter, the shape of the convex portion 123b2 provided on the side opposite to the thrust direction of the cylinder liner 123b will be described.
　凸状部１２３ｂ２の第１端部Ｂ１に最も接近している端部（第１端部近傍部）の上面は基準仮想平面ＶＰから第１距離Ｌ１１だけ離間している。
　凸状部１２３ｂ２の第２端部Ｂ２に最も接近している端部（第２端部近傍部）の上面は基準仮想平面ＶＰから第１距離Ｌ１２だけ離間している。
　凸状部１２３ｂ２のピストン２３ｃの反スラスト方向に位置する部分である反スラスト方向部Ｂ４の上面は基準仮想平面ＶＰから第４距離Ｌ１４だけ離間している。 The upper surface of the end portion (the first end portion vicinity portion) closest to the first end portion B1 of the convex portion 123b2 is separated from the reference virtual plane VP by the first distance L11.
The upper surface of the end portion (second end vicinity portion) closest to the second end B2 of the convex portion 123b2 is separated from the reference virtual plane VP by the first distance L12.
The upper surface of the anti-thrust direction portion B4, which is the portion of the convex portion 123b2 located in the anti-thrust direction of the piston 23c, is separated from the reference virtual plane VP by the fourth distance L14.
　第１距離Ｌ１１は、第４距離Ｌ１４よりも短い。
　第２距離Ｌ１２は、第４距離Ｌ１４よりも短い。
　第１距離Ｌ１１は第２距離Ｌ１２と等しくてもよく、相違していてもよい。 The first distance L11 is shorter than the fourth distance L14.
The second distance L12 is shorter than the fourth distance L14.
The first distance L11 may be equal to or different from the second distance L12.
　第１端部近傍部と反スラスト方向部Ｂ４との間の凸状部１２３ｂ２の上面は、反スラスト方向部Ｂ４から第１端部近傍部に近づくにつれて基準仮想平面ＶＰに徐々に近づく。
　第２端部近傍部と反スラスト方向部Ｂ４との間の凸状部１２３ｂ２の上面は、反スラスト方向部Ｂ４から第２端部近傍部に近づくにつれて基準仮想平面ＶＰに徐々に近づく。 The upper surface of the convex portion 123b2 between the vicinity of the first end portion and the anti-thrust direction portion B4 gradually approaches the reference virtual plane VP as it approaches the vicinity of the first end portion from the anti-thrust direction portion B4.
The upper surface of the convex portion 123b2 between the vicinity of the second end portion and the anti-thrust direction portion B4 gradually approaches the reference virtual plane VP from the anti-thrust direction portion B4 toward the vicinity of the second end portion.
　このように構成された内燃機関によれば、オイルリングＯＲによりシリンダ２３ａの内壁（即ち、シリンダライナ１２３ｂの内壁）からクランクケース２１（及びオイルパン２２）に向けて掻き落とされる潤滑油は、第１端部Ｂ１及び第２端部Ｂ２に向けて集中する（図５における破線の矢印を参照。）。 According to the internal combustion engine thus configured, the lubricating oil scraped off from the inner wall of the cylinder 23a (that is, the inner wall of the cylinder liner 123b) toward the crankcase 21 (and the oil pan 22) by the oil ring OR is It concentrates toward the 1st edge part B1 and 2nd edge part B2 (refer the arrow of the broken line in FIG. 5).
　即ち、シリンダ２３ａの内壁（即ち、シリンダライナ１２３ｂの内壁）からクランクケース２１（及びオイルパン２２）に向けて掻き落とされる潤滑油は、凸状部１２３ｂ２の上面に沿って流動して「第１端部Ｂ１及び第２端部Ｂ２」に向けて集中し、その後、、縦壁部（クランクジャーナル取付け部）２１ｂの表面に沿って滑落する。よって、掻き落とされる潤滑油が、高速で回転・運動している部材（クランクピン２１２、クランクアーム２１３、バランスウエイト２１４及びコネクティングロッド２３ｄ等）に「落下しながら衝突して飛散する」ことがない。その結果、クランクケース室において発生するオイルミストの量を低減することができるので、ブローバイガス還流装置５０によって吸気通路部３０を構成する部材（特に、コンプレッサ６１）に流入する「煤等のパティキュレートマターを取り込んだオイルミストＯＭ」の量を低減することができる。従って、吸気通路部３０を構成する部材へのデポジットの堆積量を低減することができる。 That is, the lubricating oil scraped off from the inner wall of the cylinder 23a (that is, the inner wall of the cylinder liner 123b) toward the crankcase 21 (and the oil pan 22) flows along the upper surface of the convex portion 123b2 and becomes “first It concentrates toward the end portion B1 and the second end portion B2 ", and then slides down along the surface of the vertical wall portion (crank journal mounting portion) 21b. Therefore, the lubricant to be scraped off does not “collision and scatter while falling” to members (crank pin 212, crank arm 213, balance weight 214, connecting rod 23d, etc.) rotating and moving at high speed. . As a result, it is possible to reduce the amount of oil mist generated in the crankcase chamber, so that the blow-by gas recirculation device 50 flows into the members (particularly, the compressor 61) constituting the intake passage portion 30 as “particulates such as soot”. It is possible to reduce the amount of oil mist OM incorporating the matter. Accordingly, it is possible to reduce the amount of deposit accumulated on the members constituting the intake passage portion 30.
＜第３実施形態＞
　本発明の第３実施形態に係る内燃機関は、シリンダライナ１２３ｂに代わるシリンダライナ２２３ｂが、凸状部１２３ｂ２に代わる「図７に断面形状を示した凹状部２２３ｂ２」を備えている点においてのみ、第２実施形態に係る内燃機関と相違している。凹状部２２３ｂ２の軸線は、シリンダライナ１２３ｂの凸状部１２３ｂ２の軸線と略同一である。また、凹状部２２３ｂ２は、ピストン２３ｃの可動領域よりも下方（クランクケース２１側）に設けられている。凹状部２２３ｂ２は、シリンダライナ２２３ｂの内壁（内周壁）に形成された溝（潤滑油誘導路形成部）であると言うこともできる。 <Third Embodiment>
In the internal combustion engine according to the third embodiment of the present invention, only in that the cylinder liner 223b, which replaces the cylinder liner 123b, includes the “concave portion 223b2 whose cross-sectional shape is shown in FIG. 7” instead of the convex portion 123b2. This is different from the internal combustion engine according to the second embodiment. The axis of the concave portion 223b2 is substantially the same as the axis of the convex portion 123b2 of the cylinder liner 123b. The concave portion 223b2 is provided below the movable region of the piston 23c (on the crankcase 21 side). It can also be said that the concave portion 223b2 is a groove (lubricating oil guide path forming portion) formed in the inner wall (inner peripheral wall) of the cylinder liner 223b.
　この第３実施形態によっても、オイルリングＯＲによりシリンダ２３ａの内壁（即ち、シリンダライナ１２３ｂの内壁）からクランクケース２１に向けて掻き落とされる潤滑油は、凹状部２２３ｂ２に沿って流れ、第１端部Ｂ１及び第２端部Ｂ２に向けて集中し、その後、縦壁部（クランクジャーナル取付け部）２１ｂの表面に沿って滑落する。よって、掻き落とされる潤滑油が、高速で回転・運動している部材に「落下しながら衝突して飛散する」ことがない。その結果、第１実施形態及び第２実施形態と同様の理由により、吸気通路部３０を構成する部材へのデポジットの堆積量を低減することができる。 Also in the third embodiment, the lubricating oil scraped off from the inner wall of the cylinder 23a (that is, the inner wall of the cylinder liner 123b) toward the crankcase 21 by the oil ring OR flows along the concave portion 223b2, and the first end. It concentrates toward the part B1 and the second end part B2, and then slides down along the surface of the vertical wall part (crank journal attaching part) 21b. Therefore, the lubricant to be scraped off does not “collision and scatter while falling” on a member that is rotating and moving at high speed. As a result, for the same reason as in the first embodiment and the second embodiment, it is possible to reduce the amount of deposit deposited on the members constituting the intake passage portion 30.
＜第４実施形態＞
　本発明の第４実施形態に係る内燃機関は、図８の（Ａ）乃至（Ｄ）に示したように、内燃機関１０のシリンダライナ２３ｂに置換されるシリンダライナ３２３ｂの形状がシリンダライナ２３ｂの形状と相違する点においてのみ内燃機関１０と相違している。従って、以下、この相違点を中心として説明する。 <Fourth embodiment>
In the internal combustion engine according to the fourth embodiment of the present invention, as shown in FIGS. 8A to 8D, the shape of the cylinder liner 323b replaced with the cylinder liner 23b of the internal combustion engine 10 is the same as that of the cylinder liner 23b. It differs from the internal combustion engine 10 only in the point different from the shape. Therefore, hereinafter, this difference will be mainly described.
　このシリンダライナ３２３ｂは、従来のシリンダライナと同様に円筒形（上面及び下面が開放した中空円筒形）である。従って、シリンダライナ３２３ｂの下端部（シリンダライナ３２３ｂのクランクケース２１側の端部）３２３ｂ１は平坦であって、基準仮想平面ＶＰと平行である。 The cylinder liner 323b has a cylindrical shape (a hollow cylindrical shape with an open upper surface and a lower surface) as in the conventional cylinder liner. Accordingly, the lower end portion of the cylinder liner 323b (the end portion of the cylinder liner 323b on the crankcase 21 side) 323b1 is flat and parallel to the reference virtual plane VP.
　但し、シリンダライナ３２３ｂは、シリンダライナ３２３ｂの下端部３２３ｂ１に同下端部３２３ｂ１から内方（シリンダライナ３２３ｂの中心軸線ＣＬ３の方向）に突出した庇（ひさし）部３２３ｂ２を備えている。この庇部３２３ｂ２は、高速で回転・運動している部材（クランクピン２１２、クランクアーム２１３、バランスウエイト２１４及びコネクティングロッド２３ｄ等）の運動を阻害しない位置及び長さ（シリンダライナ３２３ｂの径方向長さ）を有している。 However, the cylinder liner 323b is provided with a collar portion 323b2 projecting inward (in the direction of the central axis CL3 of the cylinder liner 323b) from the lower end portion 323b1 at the lower end portion 323b1 of the cylinder liner 323b. The flange 323b2 has a position and a length (the length of the cylinder liner 323b in the radial direction) that does not hinder the movement of the members (crank pin 212, crank arm 213, balance weight 214, connecting rod 23d, etc.) that rotate and move at high speed. A).
　更に、庇部３２３ｂ２は、シリンダライナ３２３ｂの下端部３２３ｂ１の部分であって、シリンダライナ３２３ｂをシリンダ２３ａの中心軸線（従って、シリンダライナ３２３ｂの中心軸線ＣＬ３）に沿って見た場合（図８の（Ｂ）を参照。）、クランクシャフト２１ａの軸線ＳＣと重なる一対の部分の部分である「第１端部Ｃ１及び第２端部Ｃ２」のそれぞれ（即ち、第１端部Ｃ１及び第２端部Ｃ２の双方）を含む所定領域を除く部分に設けられている。 Further, the flange portion 323b2 is a portion of the lower end portion 323b1 of the cylinder liner 323b, and when the cylinder liner 323b is viewed along the center axis of the cylinder 23a (therefore, the center axis CL3 of the cylinder liner 323b) (see FIG. 8). (See (B).), “First end portion C1 and second end portion C2” that are portions of a pair of portions overlapping the axis SC of the crankshaft 21a (ie, the first end portion C1 and the second end portion). It is provided in a portion excluding a predetermined region including both of the part C2.
　これにより、オイルリングＯＲによりシリンダライナ３２３ｂの内壁からクランクケース２１に向けて掻き落とされる潤滑油は、「第１端部Ｃ１及び第２端部Ｃ２」のそれぞれを含む所定領域に向けて「集中」させられる。即ち、庇部３２３ｂ２は、潤滑油を「第１端部Ｃ１及び第２端部Ｃ２」のそれぞれに集中させる潤滑油誘導構造を有している。 Thus, the lubricating oil scraped off from the inner wall of the cylinder liner 323b toward the crankcase 21 by the oil ring OR is “concentrated” toward a predetermined region including each of the “first end C1 and second end C2”. " That is, the flange 323b2 has a lubricating oil guiding structure that concentrates the lubricating oil on each of the “first end C1 and second end C2”.
　従って、第４実施形態によっても、クランクケース２１に向けて掻き落とされる潤滑油は、縦壁部（クランクジャーナル取付け部）２１ｂの表面に沿って滑落する。よって、掻き落とされる潤滑油が、高速で回転・運動している部材に「落下しながら衝突して飛散する」ことがない。その結果、第１実施形態及び第２実施形態等と同様の理由により、吸気通路部３０を構成する部材へのデポジットの堆積量を低減することができる。 Therefore, also in the fourth embodiment, the lubricating oil scraped off toward the crankcase 21 slides along the surface of the vertical wall portion (crank journal mounting portion) 21b. Therefore, the lubricant to be scraped off does not “collision and scatter while falling” on a member that is rotating and moving at high speed. As a result, for the same reason as in the first embodiment and the second embodiment, it is possible to reduce the amount of deposit deposited on the members constituting the intake passage portion 30.
＜第５実施形態＞
　本発明の第５実施形態に係る内燃機関は、図９の（Ａ）乃至（Ｄ）に示したように、内燃機関１０のシリンダライナ２３ｂに置換されるシリンダライナ４２３ｂの形状がシリンダライナ２３ｂの形状と相違する点においてのみ内燃機関１０と相違している。従って、以下、この相違点を中心として説明する。 <Fifth Embodiment>
In the internal combustion engine according to the fifth embodiment of the present invention, as shown in FIGS. 9A to 9D, the shape of the cylinder liner 423b replaced with the cylinder liner 23b of the internal combustion engine 10 is the same as that of the cylinder liner 23b. It differs from the internal combustion engine 10 only in the point different from the shape. Therefore, hereinafter, this difference will be mainly described.
　シリンダライナ４２３ｂは、シリンダライナ４２３ｂのクランクケース２１側の端部４２３ｂ１の部分であって、シリンダライナ４２３ｂをシリンダ２３ａの中心軸線（従って、シリンダライナ４２３ｂの中心軸線ＣＬ４）に沿って見た場合（図９の（Ｄ）を参照。）、クランクシャフト２１ａの軸線ＳＣと重なる一対の部分である「第１端部Ｄ１及び第２端部Ｄ２」の何れか一方のみ（この場合、第１端部Ｄ１のみ）へ、オイルリングＯＲによりシリンダライナ４２３ｂの内壁からクランクケース２１に向けて掻き落とされる潤滑油を「集中」させる構造（潤滑油誘導構造）を有している。 The cylinder liner 423b is a portion of the end portion 423b1 of the cylinder liner 423b on the crankcase 21 side, and the cylinder liner 423b is viewed along the center axis of the cylinder 23a (therefore, the center axis CL4 of the cylinder liner 423b) ( 9D), only one of “first end D1 and second end D2” that is a pair of portions overlapping the axis SC of the crankshaft 21a (in this case, the first end portion). D1 only) has a structure (lubricating oil guiding structure) for “concentrating” the lubricating oil scraped off from the inner wall of the cylinder liner 423b toward the crankcase 21 by the oil ring OR.
　より具体的に述べると、第１端部Ｄ１は、基準仮想平面ＶＰから第５距離Ｌ４１だけ離間している。第２端部Ｄ２は、基準仮想平面ＶＰから「第５距離Ｌ４１よりも長い第６距離Ｌ４２」だけ離間している。 More specifically, the first end D1 is separated from the reference virtual plane VP by the fifth distance L41. The second end D2 is separated from the reference virtual plane VP by “a sixth distance L42 longer than the fifth distance L41”.
　そして、第１端部Ｄ１と第２端部Ｄ２との間のシリンダライナ４２３ｂの下端部４２３ｂ１は、第２端部Ｄ２から第１端部Ｄ１に近づくにつれて基準仮想平面ＶＰに徐々に近づく。換言すると、第１端部Ｄ１と第２端部Ｄ２との間のシリンダライナ４２３ｂの下端部４２３ｂ１は、スラスト方向（又は反スラスト方向）に沿ってシリンダライナ４２３ｂを見た場合（図９の（Ｂ）を参照。）において滑らかな曲線状であり、第１端部Ｄ１と第２端部Ｄ２との間のシリンダライナ４２３ｂの下端部４２３ｂ１と基準仮想平面ＶＰとの距離は第２端部Ｄ２から第１端部Ｄ１に近づくにつれて単調減少する。 The lower end portion 423b1 of the cylinder liner 423b between the first end portion D1 and the second end portion D2 gradually approaches the reference virtual plane VP from the second end portion D2 toward the first end portion D1. In other words, the lower end 423b1 of the cylinder liner 423b between the first end D1 and the second end D2 is viewed when the cylinder liner 423b is viewed along the thrust direction (or anti-thrust direction) ( B).), The distance between the lower end 423b1 of the cylinder liner 423b and the reference virtual plane VP between the first end D1 and the second end D2 is the second end D2. Decreases monotonically as it approaches the first end D1.
　このように構成された内燃機関によれば、オイルリングＯＲによりシリンダ２３ａの内壁（即ち、シリンダライナ４２３ｂの内壁）からクランクケース２１に向けて掻き落とされる潤滑油は、第１端部Ｄ１に向けて集中する（図９における破線の矢印を参照。）。 According to the internal combustion engine thus configured, the lubricating oil scraped off from the inner wall of the cylinder 23a (that is, the inner wall of the cylinder liner 423b) toward the crankcase 21 by the oil ring OR is directed toward the first end D1. (See the dashed arrows in FIG. 9).
　即ち、オイルリングＯＲにより掻き落とされる潤滑油は、シリンダライナ４２３ｂの下端部に沿って流動して第１端部Ｄ１に向けて集中し、その後、、縦壁部（クランクジャーナル取付け部）２１ｂの表面に沿って滑落する。よって、掻き落とされる潤滑油が、高速で回転・運動している部材（クランクピン２１２、クランクアーム２１３、バランスウエイト２１４及びコネクティングロッド２３ｄ等）に「落下しながら衝突して飛散する」ことがない。その結果、第１実施形態及び第２実施形態と同様の理由により、吸気通路部３０を構成する部材へのデポジットの堆積量を低減することができる。 That is, the lubricating oil scraped off by the oil ring OR flows along the lower end portion of the cylinder liner 423b and concentrates toward the first end portion D1, and then the vertical wall portion (crank journal mounting portion) 21b. Slide down along the surface. Therefore, the lubricant to be scraped off does not “collision and scatter while falling” to members (crank pin 212, crank arm 213, balance weight 214, connecting rod 23d, etc.) rotating and moving at high speed. . As a result, for the same reason as in the first embodiment and the second embodiment, it is possible to reduce the amount of deposit deposited on the members constituting the intake passage portion 30.
＜第５実施形態の変形例＞
　本発明の第５実施形態の変形例は、内燃機関１０がシリンダライナを備えない機関である場合において、シリンダライナ４２３ｂに代えて、シリンダブロック２３が形成するシリンダ（ボア）の下端部（クランクケース２１側の端部）が、第５実施形態のシリンダライナ４２３ｂと同様の形状を有している点のみにおいて、第５実施形態と相違している。 <Modification of Fifth Embodiment>
In a modification of the fifth embodiment of the present invention, when the internal combustion engine 10 is an engine that does not include a cylinder liner, a lower end portion (crankcase) of a cylinder (bore) formed by the cylinder block 23 instead of the cylinder liner 423b. The end portion on the 21st side is different from the fifth embodiment only in that it has the same shape as the cylinder liner 423b of the fifth embodiment.
　従って、シリンダ２３ａの内壁からクランクケース２１に向けて掻き落とされる潤滑油は、縦壁部（クランクジャーナル取付け部）２１ｂに沿って滑落するので、高速で回転・運動している部材に「落下しながら衝突して飛散する」ことがない。よって、クランクケース室内のオイルミストの量を低減することができるので、煤等のパティキュレートマターを取り込んだオイルミストＯＭの量を低減することができる。従って、吸気通路部３０を構成する部材へのデポジットの堆積量を低減することができる。 Accordingly, the lubricating oil scraped off from the inner wall of the cylinder 23a toward the crankcase 21 slides along the vertical wall portion (crank journal mounting portion) 21b, so that it “drops” on the member that rotates and moves at high speed. "There is no collision and scattering". Therefore, since the amount of oil mist in the crankcase chamber can be reduced, the amount of oil mist OM incorporating particulate matter such as soot can be reduced. Accordingly, it is possible to reduce the amount of deposit accumulated on the members constituting the intake passage portion 30.
＜第６実施形態＞
　本発明の第６実施形態は、図１０に示したように、シリンダライナ４２３ｂに置換されるシリンダライナ５２３ｂの形状がシリンダライナ４２３ｂの形状と相違する点においてのみ第５実施形態と相違している。従って、以下、この相違点を中心として説明する。 <Sixth Embodiment>
As shown in FIG. 10, the sixth embodiment of the present invention differs from the fifth embodiment only in that the shape of the cylinder liner 523b replaced with the cylinder liner 423b is different from the shape of the cylinder liner 423b. . Therefore, hereinafter, this difference will be mainly described.
　このシリンダライナ５２３ｂは、従来のシリンダライナと同様に円筒形（上面及び下面が開放した中空円筒形）である。従って、シリンダライナ５２３ｂの下端部（シリンダライナ５２３ｂのクランクケース２１側の端部）５２３ｂ１は平坦であって、基準仮想平面ＶＰと平行である。 The cylinder liner 523b has a cylindrical shape (a hollow cylindrical shape with an open upper surface and a lower surface) as in the conventional cylinder liner. Therefore, the lower end portion of the cylinder liner 523b (the end portion of the cylinder liner 523b on the crankcase 21 side) 523b1 is flat and parallel to the reference virtual plane VP.
　但し、シリンダライナ５２３ｂは、その内壁（内周壁）にシリンダライナ５２３ｂの内方に突出した凸状部（「***部、突出部、尾根部又は潤滑油誘導路形成部」とも言うことができる。）５２３ｂ２を備えている。この凸状部５２３ｂ２は、凸状部５２３ｂ２の軸線が「シリンダライナ４２３ｂの下端部２３ｂ１が描く線」と略同一となるように延在している。従って、凸状部５２３ｂ２は、ピストン２３ｃの可動領域よりも下方（クランクケース２１側）に設けられている。更に、凸状部５２３ｂ２は、高速で回転・運動している部材（クランクピン２１２、クランクアーム２１３、バランスウエイト２１４及びコネクティングロッド２３ｄ等）の運動を阻害しない高さ（シリンダライナ５２３ｂの径方向長さ）を有している。 However, the cylinder liner 523b can also be referred to as a projecting portion ("a raised portion, a protruding portion, a ridge portion, or a lubricating oil guide path forming portion") that protrudes inward of the cylinder liner 523b on its inner wall (inner peripheral wall). ) 523b2. The convex portion 523b2 extends so that the axis of the convex portion 523b2 is substantially the same as the “line drawn by the lower end portion 23b1 of the cylinder liner 423b”. Accordingly, the convex portion 523b2 is provided below the movable region of the piston 23c (on the crankcase 21 side). Further, the convex portion 523b2 has a height (the length of the cylinder liner 523b in the radial direction) that does not hinder the movement of members (crank pin 212, crank arm 213, balance weight 214, connecting rod 23d, etc.) that rotate and move at high speed. A).
　即ち、凸状部５２３ｂ２は、シリンダライナ５２３ｂをシリンダの中心軸線（従って、シリンダライナ５２３ｂの中心軸線ＣＬ５）に沿って見た場合（図１０の（Ａ）を参照。）にクランクシャフト２１ａの軸線ＳＣと重なる一対の部分である「第１端部Ｅ１及び第２端部Ｅ２」の何れか一方のみ（この場合、第１端部Ｅ１のみ）へ、オイルリングＯＲによりシリンダライナ５２３ｂの内壁からクランクケース２１に向けて掻き落とされる潤滑油を「集中」させる構造・形状（潤滑油誘導構造）を有するように延在している。 That is, the convex portion 523b2 has the axis of the crankshaft 21a when the cylinder liner 523b is viewed along the center axis of the cylinder (therefore, the center axis CL5 of the cylinder liner 523b) (see FIG. 10A). Crank from the inner wall of the cylinder liner 523b by an oil ring OR to only one of the first end E1 and the second end E2 (in this case, only the first end E1) that is a pair of portions overlapping the SC. It extends so as to have a structure / shape (lubricating oil guiding structure) that “concentrates” the lubricating oil scraped off toward the case 21.
　凸状部５２３ｂ２の軸線に直交する断面の形状は、図１０（Ｂ）に示したような略長方形であってもよく、図６（Ｂ）に示した形状と同様の形状（即ち、シリンダライナ５２３ｂの中心軸線ＣＬ５方向へ延びる底部Ｔ１と、その底部Ｔ１の端部からシリンダライナ５２３ｂの上端（シリンダヘッド側）に向けて斜めに屈曲した斜面部Ｔ２とを有している形状）であってもよい。 The shape of the cross section orthogonal to the axis of the convex portion 523b2 may be a substantially rectangular shape as shown in FIG. 10B, and is the same shape as the shape shown in FIG. 523b having a bottom portion T1 extending in the direction of the central axis CL5, and a slope portion T2 that is obliquely bent from the end portion of the bottom portion T1 toward the upper end (cylinder head side) of the cylinder liner 523b). Also good.
　より具体的に述べると、図１０の（Ａ）から理解されるように、凸状部５２３ｂ２は第１端部Ｅ１を含む所定領域を除く部分に設けられている。第１端部Ｅ１の近傍における凸状部５２３ｂ２の上面（シリンダヘッド側の面）と基準仮想平面ＶＰとの距離Ｌ５１は、第２端部Ｅ３における凸状部５２３ｂ２の上面と基準仮想平面ＶＰとの距離Ｌ５２よりも小さい。凸状部５２３ｂ２の上面は、第２端部Ｅ２から第１端部Ｅ１に近づくにつれて基準仮想平面ＶＰに徐々に近づく。換言すると、第１端部Ｅ１と第２端部Ｅ２との間の凸状部５２３ｂ２の上面は、スラスト方向（又は反スラスト方向）に沿ってシリンダライナ５２３ｂを見た場合（図１０の（Ｂ）を参照。）において滑らかな曲線状であり、第１端部Ｅ１と第２端部Ｅ２との間のシリンダライナ５２３ｂの上面と基準仮想平面ＶＰとの距離は第２端部Ｅ２から第１端部Ｅ１に近づくにつれて単調減少する。 More specifically, as can be understood from FIG. 10A, the convex portion 523b2 is provided in a portion excluding a predetermined region including the first end E1. The distance L51 between the upper surface (cylinder head side surface) of the convex portion 523b2 near the first end E1 and the reference virtual plane VP is equal to the upper surface of the convex portion 523b2 and the reference virtual plane VP at the second end E3. Is smaller than the distance L52. The upper surface of the convex portion 523b2 gradually approaches the reference virtual plane VP as it approaches the first end E1 from the second end E2. In other words, the upper surface of the convex portion 523b2 between the first end E1 and the second end E2 is viewed from the cylinder liner 523b along the thrust direction (or anti-thrust direction) ((B of FIG. 10). The distance between the upper surface of the cylinder liner 523b and the reference virtual plane VP between the first end E1 and the second end E2 is the first end E2 to the first end E2. It decreases monotonously as it approaches the end E1.
　従って、オイルリングＯＲによりシリンダ２３ａの内壁（即ち、シリンダライナ５２３ｂの内壁）からクランクケース２１に向けて掻き落とされる潤滑油は、第１端部Ｅ１に向けて集中する（図１０の（Ｂ）における破線の矢印を参照。）。 Accordingly, the lubricating oil scraped off from the inner wall of the cylinder 23a (that is, the inner wall of the cylinder liner 523b) by the oil ring OR toward the crankcase 21 is concentrated toward the first end E1 ((B) of FIG. 10). (See the dashed arrows in.)
　即ち、オイルリングＯＲにより掻き落とされる潤滑油は、凸状部５２３ｂ２の上面に沿って流動して第１端部Ｅ１に向けて集中し、その後、、縦壁部（クランクジャーナル取付け部）２１ｂの表面に沿って滑落する。よって、掻き落とされる潤滑油が、高速で回転・運動している部材（クランクピン２１２、クランクアーム２１３、バランスウエイト２１４及びコネクティングロッド２３ｄ等）に「落下しながら衝突して飛散する」ことがない。その結果、第１実施形態及び第２実施形態と同様の理由により、吸気通路部３０を構成する部材へのデポジットの堆積量を低減することができる。 That is, the lubricating oil scraped off by the oil ring OR flows along the upper surface of the convex portion 523b2 and concentrates toward the first end E1, and then the vertical wall portion (crank journal mounting portion) 21b. Slide down along the surface. Therefore, the lubricant to be scraped off does not “collision and scatter while falling” to members (crank pin 212, crank arm 213, balance weight 214, connecting rod 23d, etc.) rotating and moving at high speed. . As a result, for the same reason as in the first embodiment and the second embodiment, it is possible to reduce the amount of deposit deposited on the members constituting the intake passage portion 30.
＜第７実施形態＞
　本発明の第７実施形態に係る内燃機関は、シリンダライナ５２３ｂに代わるシリンダライナ６２３ｂが、凸状部５２３ｂ２に代わる「図１１に断面形状を示した凹状部６２３ｂ２」を備えている点においてのみ、第６実施形態に係る内燃機関と相違している。凹状部６２３ｂ２は、凹状部６２３ｂ２の軸線がシリンダライナ５２３ｂの凸状部５２３ｂ２の軸線と略同一となるように、延在している。また、凹状部６２３ｂ２は、ピストン２３ｃの可動領域よりも下方（クランクケース２１側）に設けられている。凹状部６２３ｂ２は、シリンダライナ２２３ｂの内壁（内周壁）に形成された溝（潤滑油誘導路形成部）であると言うこともできる。 <Seventh embodiment>
In the internal combustion engine according to the seventh embodiment of the present invention, only in that a cylinder liner 623b replacing the cylinder liner 523b includes a “concave portion 623b2 whose sectional shape is shown in FIG. 11” instead of the convex portion 523b2. This is different from the internal combustion engine according to the sixth embodiment. The concave portion 623b2 extends so that the axis of the concave portion 623b2 is substantially the same as the axis of the convex portion 523b2 of the cylinder liner 523b. The concave portion 623b2 is provided below (on the crankcase 21 side) the movable region of the piston 23c. It can also be said that the recessed portion 623b2 is a groove (lubricating oil guide path forming portion) formed in the inner wall (inner peripheral wall) of the cylinder liner 223b.
　この第７実施形態によっても、オイルリングＯＲによりシリンダ２３ａの内壁（即ち、シリンダライナ６２３ｂの内壁）からクランクケース２１に向けて掻き落とされる潤滑油は、凹状部６２３ｂ２に沿って流れ、第１端部Ｅ１に向けて集中し、その後、縦壁部（クランクジャーナル取付け部）２１ｂの表面に沿って滑落する。よって、掻き落とされる潤滑油が、高速で回転・運動している部材に「落下しながら衝突して飛散する」ことがない。その結果、第１実施形態及び第２実施形態と同様の理由により、吸気通路部３０を構成する部材へのデポジットの堆積量を低減することができる。 Also according to the seventh embodiment, the lubricating oil scraped off from the inner wall of the cylinder 23a (that is, the inner wall of the cylinder liner 623b) toward the crankcase 21 by the oil ring OR flows along the concave portion 623b2, and the first end. It concentrates toward the part E1, and then slides down along the surface of the vertical wall part (crank journal attaching part) 21b. Therefore, the lubricant to be scraped off does not “collision and scatter while falling” on a member that is rotating and moving at high speed. As a result, for the same reason as in the first embodiment and the second embodiment, it is possible to reduce the amount of deposit deposited on the members constituting the intake passage portion 30.
＜第８実施形態＞
　本発明の第８実施形態に係る内燃機関は、図１２の（Ａ）乃至（Ｄ）に示したように、内燃機関１０のシリンダライナ２３ｂに置換されるシリンダライナ７２３ｂの形状がシリンダライナ２３ｂの形状と相違する点においてのみ内燃機関１０と相違している。従って、以下、この相違点を中心として説明する。 <Eighth Embodiment>
In the internal combustion engine according to the eighth embodiment of the present invention, as shown in FIGS. 12A to 12D, the cylinder liner 723b replaced with the cylinder liner 23b of the internal combustion engine 10 has a cylinder liner 23b shape. It differs from the internal combustion engine 10 only in the point different from the shape. Therefore, hereinafter, this difference will be mainly described.
　このシリンダライナ７２３ｂは、従来のシリンダライナと同様に円筒形（上面及び下面が開放した中空円筒形）である。従って、シリンダライナ７２３ｂの下端部（シリンダライナ７２３ｂのクランクケース２１側の端部）７２３ｂ１は平坦であって、基準仮想平面ＶＰと平行である。 This cylinder liner 723b has a cylindrical shape (a hollow cylindrical shape with the upper surface and the lower surface opened) as in the conventional cylinder liner. Accordingly, the lower end portion of the cylinder liner 723b (the end portion of the cylinder liner 723b on the crankcase 21 side) 723b1 is flat and parallel to the reference virtual plane VP.
　但し、シリンダライナ７２３ｂは、シリンダライナ７２３ｂの下端部７２３ｂ１に同下端部７２３ｂ１から内方（シリンダライナ７２３ｂの中心軸線ＣＬ７の方向）に突出した庇（ひさし）部７２３ｂ２を備えている。この庇部７２３ｂ２は、高速で回転・運動している部材（クランクピン２１２、クランクアーム２１３、バランスウエイト２１４及びコネクティングロッド２３ｄ等）の運動を阻害しない位置及び長さ（シリンダライナ７２３ｂの径方向長さ）を有している。 However, the cylinder liner 723b is provided with a collar portion 723b2 projecting inward (in the direction of the central axis CL7 of the cylinder liner 723b) from the lower end portion 723b1 at the lower end portion 723b1 of the cylinder liner 723b. The flange portion 723b2 has a position and a length (the length of the cylinder liner 723b in the radial direction) that does not hinder the movement of members (crank pin 212, crank arm 213, balance weight 214, connecting rod 23d, etc.) that rotate and move at high speed. A).
　更に、庇部３２３ｂ２は、シリンダライナ３２３ｂの下端部３２３ｂ１の部分であって、シリンダライナ７２３ｂをシリンダ２３ａの中心軸線（従って、シリンダライナ７２３ｂの中心軸線ＣＬ７）に沿って見た場合（図１２の（Ｂ）を参照。）、クランクシャフト２１ａの軸線ＳＣと重なる一対の部分である「第１端部Ｆ１を含む所定領域」を除く部分に設けられている。 Further, the flange portion 323b2 is a portion of the lower end portion 323b1 of the cylinder liner 323b, and when the cylinder liner 723b is viewed along the center axis of the cylinder 23a (therefore, the center axis CL7 of the cylinder liner 723b) (see FIG. 12). (See (B).), Provided in a portion excluding the “predetermined region including the first end portion F1” that is a pair of portions overlapping the axis SC of the crankshaft 21a.
　これにより、オイルリングＯＲによりシリンダライナ７２３ｂの内壁からクランクケース２１に向けて掻き落とされる潤滑油は、「第１端部Ｆ１を含む所定領域」に向けて「集中」させられる。即ち、庇部７２３ｂ２は、潤滑油を「第１端部Ｆ１に向けて集中させる潤滑油誘導構造」を有している。 Thereby, the lubricating oil scraped off from the inner wall of the cylinder liner 723b toward the crankcase 21 by the oil ring OR is “concentrated” toward the “predetermined region including the first end portion F1”. That is, the flange portion 723b2 has a “lubricating oil guiding structure that concentrates the lubricating oil toward the first end portion F1”.
　従って、第８実施形態によっても、クランクケース２１に向けて掻き落とされる潤滑油は、縦壁部（クランクジャーナル取付け部）２１ｂの表面に沿って滑落する。よって、掻き落とされる潤滑油が、高速で回転・運動している部材に「落下しながら衝突して飛散する」ことがない。その結果、第１実施形態及び第２実施形態等と同様の理由により、吸気通路部３０を構成する部材へのデポジットの堆積量を低減することができる。 Therefore, also in the eighth embodiment, the lubricating oil scraped off toward the crankcase 21 slides along the surface of the vertical wall portion (crank journal mounting portion) 21b. Therefore, the lubricant to be scraped off does not “collision and scatter while falling” on a member that is rotating and moving at high speed. As a result, for the same reason as in the first embodiment and the second embodiment, it is possible to reduce the amount of deposit deposited on the members constituting the intake passage portion 30.
　以上、説明したように、本発明の各実施形態に係る内燃機関は、シリンダの内壁（シリンダライナー又はシリンダそのものの内壁）の下端部（クランクケース側の端部の部分）であってクランク軸方向に存在する一対の部分である第１及び第２端部の少なくとも一方に向けて、オイルリングＯＲによりシリンダの内壁からクランクケースに向けて掻き落とされる潤滑油を集中させる構造を有している。 As described above, the internal combustion engine according to each embodiment of the present invention is the lower end portion (the end portion on the crankcase side) of the inner wall of the cylinder (the inner wall of the cylinder liner or the cylinder itself) in the crankshaft direction. The lubricating oil scraped off from the inner wall of the cylinder toward the crankcase by the oil ring OR is concentrated toward at least one of the pair of first and second end portions.
　従って、シリンダの内壁からクランクケースに向けて掻き落とされる潤滑油が、高速で回転・運動している部材（クランクアーム、クランクピン、バランスウエイト及び／又はコネクティングロッド等）に落下・衝突及び飛散しない。よって、クランクケース内に発生するオイルミストの量を低減することができ、その結果、吸気通路構成部材に付着するデポジットの量を低減することができる。 Therefore, the lubricating oil scraped off from the inner wall of the cylinder toward the crankcase does not drop, collide, or scatter on members that rotate and move at high speed (such as crank arms, crank pins, balance weights and / or connecting rods). . Therefore, the amount of oil mist generated in the crankcase can be reduced, and as a result, the amount of deposit attached to the intake passage constituting member can be reduced.
　本発明は上記実施形態に限定されることはなく、本発明の範囲内において種々の変形例を採用することができる。例えば、オイルリングＯＲによりシリンダ２３ａの内壁からクランクケースに向けて掻き落とされる潤滑油の全てが、第１及び第２端部の何れかからクランクケース２１側へと落下する必要はなく、掻き落とされる潤滑油の大部分が第１及び第２端部の何れかからクランクケース２１側へと落下すればよい。 The present invention is not limited to the above embodiment, and various modifications can be employed within the scope of the present invention. For example, it is not necessary for all of the lubricating oil scraped off from the inner wall of the cylinder 23a toward the crankcase by the oil ring OR to fall to the crankcase 21 side from either the first or second end, and is scraped off. It suffices for most of the lubricating oil to fall from either the first or second end to the crankcase 21 side.
　更に、例えば、図３及び図１０に示した凸状部に代え、同凸状部が存在している部分に「潤滑油との濡れ性が極めて良好な帯状の皮膜」を形成してもよい。また、本発明は、Ｖ型エンジンに適用しても差し支えない。更に、本発明はターボチャージャを備えない内燃機関に適用することもできる。加えて、図３に示したシリンダライナ２３ｂは、その下端部２３ｂ１であって「第１端部Ａ１を含む所定領域及び第２端部Ａ２を含む所定領域」の両領域を除く部分に「シリンダライナ２３ｂの内壁からシリンダライナの中心軸ＣＬ方向に延びる庇部」を有していてもよい。同様に、図９に示したシリンダライナ４２３ｂは、その下端部４２３ｂ１であって「第１端部Ｄ１を含む所定領域」を除く部分に「シリンダライナ４２３ｂの内壁からシリンダライナの中心軸ＣＬ４方向に延びる庇部」を有していてもよい。 Further, for example, instead of the convex portion shown in FIG. 3 and FIG. 10, a “strip-like film having very good wettability with the lubricating oil” may be formed on the portion where the convex portion exists. . The present invention may be applied to a V-type engine. Furthermore, the present invention can also be applied to an internal combustion engine that does not include a turbocharger. In addition, the cylinder liner 23b shown in FIG. 3 has a cylinder portion 23b1 at the lower end portion 23b1 except for both the “predetermined region including the first end portion A1 and the predetermined region including the second end portion A2”. You may have the collar part "extended in the central axis CL direction of a cylinder liner from the inner wall of the liner 23b. Similarly, the cylinder liner 423b shown in FIG. 9 has a lower end portion 423b1 other than the “predetermined region including the first end portion D1” in the direction from the inner wall of the cylinder liner 423b toward the centerline CL4 of the cylinder liner. You may have an extending heel part.

Claims (14)

  1. 　オイルリングが設けられたピストンがシリンダ内を往復動するピストン往復動型内燃機関であって、
    　前記シリンダの内壁を構成するシリンダ内壁部と、
    　クランクシャフトを収容するクランクケース内のブローバイガスを前記機関の吸気通路へ還流させるブローバイガス還流装置と、
    　を備え、
    　前記シリンダ内壁部は、前記シリンダの内壁の前記クランクケース側の端部の部分であって前記シリンダ内壁部を前記シリンダの軸線に沿って見た場合に前記クランクシャフトの軸線と重なる一対の部分である第１及び第２端部の少なくとも一方に向けて、前記オイルリングにより前記シリンダの内壁から前記クランクケースに向けて掻き落とされる潤滑油を集中させる構造を有してなる内燃機関。     A piston reciprocating internal combustion engine in which a piston provided with an oil ring reciprocates in a cylinder;
    A cylinder inner wall constituting the inner wall of the cylinder;
    A blow-by gas recirculation device for recirculating blow-by gas in a crankcase housing the crankshaft to the intake passage of the engine;
    With
    The cylinder inner wall portion is a portion of an end portion on the crankcase side of the inner wall of the cylinder, and a pair of portions that overlap with the axis of the crankshaft when the cylinder inner wall portion is viewed along the axis of the cylinder. An internal combustion engine having a structure in which lubricating oil scraped off from an inner wall of the cylinder toward the crankcase by the oil ring is concentrated toward at least one of a first end and a second end.
  2. 　請求項１に記載の内燃機関において、
    　前記シリンダ内壁部は、前記掻き落とされる潤滑油を前記第１端部及び前記第２端部のそれぞれに向けて集中させる構造を有してなる内燃機関。     The internal combustion engine according to claim 1,
    The cylinder inner wall portion is an internal combustion engine having a structure in which the scraped lubricating oil is concentrated toward each of the first end portion and the second end portion.
  3. 　請求項２に記載の内燃機関において、
    　前記シリンダ内壁部は、前記シリンダの内壁の前記クランクシャフト側の端部が前記掻き落とされる潤滑油を前記第１端部及び前記第２端部のそれぞれに向けて集中させる形状を有するように構成されてなる内燃機関。     The internal combustion engine according to claim 2,
    The inner wall portion of the cylinder has a shape in which an end portion on the crankshaft side of the inner wall of the cylinder has a shape that concentrates the lubricant to be scraped off toward each of the first end portion and the second end portion. An internal combustion engine.
  4. 　請求項３に記載の内燃機関において、
    　前記シリンダ内壁部は、
    　前記第１端部が、前記クランクシャフトの軸線を含む平面であって前記シリンダの軸線と直交する平面である基準仮想平面から第１距離だけ離間し、
    　前記第２端部が、前記基準仮想平面から第２距離だけ離間し、
    　前記シリンダの内壁の前記クランクケース側の端部の部分であって前記ピストンのスラスト方向に位置する部分であるスラスト方向部は、前記基準仮想平面から第３距離だけ離間し、
    　前記シリンダの内壁の前記クランクケース側の端部の部分であって前記ピストンの反スラスト方向に位置する部分である反スラスト方向部が、前記基準仮想平面から第４距離だけ離間し、
    　前記第１距離が前記第３距離及び前記第４距離の何れよりも短く、
    　前記第２距離が前記第３距離及び前記第４距離の何れよりも短く、
    　前記第１端部と前記スラスト方向部との間の前記シリンダの内壁の前記クランクケース側の端部が、前記スラスト方向部から前記第１端部に近づくにつれて前記基準仮想平面に徐々に近づく形状を有し、
    　前記第２端部と前記スラスト方向部との間の前記シリンダの内壁の前記クランクケース側の端部が、前記スラスト方向部から前記第２端部に近づくにつれて前記基準仮想平面に徐々に近づく形状を有し、
    　前記第１端部と前記反スラスト方向部との間の前記シリンダの内壁の前記クランクケース側の端部が、前記反スラスト方向部から前記第１端部に近づくにつれて前記基準仮想平面に徐々に近づく形状を有し、且つ、
    　前記第２端部と前記反スラスト方向部との間の前記シリンダの内壁の前記クランクケース側の端部が、前記反スラスト方向部から前記第２端部に近づくにつれて前記基準仮想平面に徐々に近づく形状を有する、
    　ように構成されてなる内燃機関。     The internal combustion engine according to claim 3,
    The cylinder inner wall is
    The first end portion is a plane including the axis of the crankshaft and is separated from a reference virtual plane that is a plane orthogonal to the axis of the cylinder by a first distance;
    The second end is spaced a second distance from the reference virtual plane;
    A thrust direction portion, which is a portion of the inner wall of the cylinder on the crankcase side and located in the thrust direction of the piston, is separated from the reference virtual plane by a third distance,
    An anti-thrust direction portion that is a portion of the inner wall of the cylinder on the crankcase side and is located in the anti-thrust direction of the piston is separated from the reference virtual plane by a fourth distance,
    The first distance is shorter than both the third distance and the fourth distance;
    The second distance is shorter than either the third distance or the fourth distance;
    A shape in which an end on the crankcase side of an inner wall of the cylinder between the first end portion and the thrust direction portion gradually approaches the reference virtual plane from the thrust direction portion toward the first end portion. Have
    A shape in which an end on the crankcase side of the inner wall of the cylinder between the second end and the thrust direction portion gradually approaches the reference imaginary plane as it approaches the second end from the thrust direction portion. Have
    As the end on the crankcase side of the inner wall of the cylinder between the first end and the anti-thrust direction portion approaches the first end from the anti-thrust direction portion, it gradually approaches the reference virtual plane. Has an approaching shape, and
    As the end on the crankcase side of the inner wall of the cylinder between the second end and the anti-thrust direction portion approaches the second end from the anti-thrust direction portion, it gradually approaches the reference virtual plane. Having an approaching shape,
    An internal combustion engine configured as described above.
  5. 　請求項３に記載の内燃機関において、
    　前記シリンダ内壁部は、
    　前記シリンダの内壁の前記クランクケース側の端部が、
    　前記クランクシャフトの軸線を含む平面であって前記シリンダの軸線と直交する平面である基準仮想平面と平行であり、且つ、
    　前記第１端部を含む第１領域及び前記第２端部を含む第２領域の両領域を除く部分に前記シリンダの内壁から前記シリンダの軸線方向に延びる庇部を備える、
    　ように構成されてなる内燃機関。     The internal combustion engine according to claim 3,
    The cylinder inner wall is
    An end of the inner wall of the cylinder on the crankcase side is
    A plane including the axis of the crankshaft and parallel to a reference virtual plane which is a plane orthogonal to the axis of the cylinder, and
    A flange extending in the axial direction of the cylinder from the inner wall of the cylinder is provided in a portion excluding both the first region including the first end and the second region including the second end.
    An internal combustion engine configured as described above.
  6. 　請求項２に記載の内燃機関において、
    　前記シリンダ内壁部は、前記シリンダの内壁から前記シリンダの内部に向けて突出する凸状部であって前記掻き落とされる潤滑油を前記第１端部及び前記第２端部のそれぞれに向けて集中させるように前記シリンダの内壁に沿って連続的に延在する凸状部を備えるように構成されてなる内燃機関。     The internal combustion engine according to claim 2,
    The cylinder inner wall portion is a convex portion projecting from the inner wall of the cylinder toward the inside of the cylinder, and the lubricant to be scraped is concentrated toward each of the first end portion and the second end portion. An internal combustion engine configured to include a convex portion extending continuously along the inner wall of the cylinder.
  7. 　請求項２に記載の内燃機関において、
    　前記シリンダ内壁部は、前記シリンダ内壁に設けられた凹状部であって前記掻き落とされる潤滑油を前記第１端部及び前記第２端部のそれぞれに向けて集中させるように前記シリンダの内壁に沿って連続的に延在する凹状部を備えるように構成されてなる内燃機関。     The internal combustion engine according to claim 2,
    The cylinder inner wall portion is a concave portion provided in the cylinder inner wall, and is formed on the inner wall of the cylinder so as to concentrate the lubricant to be scraped off toward each of the first end portion and the second end portion. An internal combustion engine configured to include a concave portion extending continuously along the same.
  8. 　請求項１に記載の内燃機関において、
    　前記シリンダ内壁部は、前記第１端部及び前記第２端部のうち前記第１端部のみに向けて前記掻き落とされる潤滑油を集中させる構造を有してなる内燃機関。     The internal combustion engine according to claim 1,
    The internal combustion engine having a structure in which the cylinder inner wall portion has a structure for concentrating the lubricant oil scraped off toward only the first end portion of the first end portion and the second end portion.
  9. 　請求項８に記載の内燃機関において、
    　前記シリンダ内壁部は、前記シリンダの内壁の前記クランクシャフト側の端部が前記掻き落とされる潤滑油を前記第１端部及び前記第２端部のうち前記第１端部のみに向けて集中させる形状を有するように構成されてなる内燃機関。     The internal combustion engine according to claim 8,
    The cylinder inner wall portion concentrates lubricating oil scraped off at the crankshaft side end portion of the inner wall of the cylinder toward only the first end portion of the first end portion and the second end portion. An internal combustion engine configured to have a shape.
  10. 　請求項９に記載の内燃機関において、
    　前記シリンダ内壁部は、
    　前記第１端部が、前記クランクシャフトの軸線を含む平面であって前記シリンダの軸線と直交する平面である基準仮想平面から第５距離だけ離間し、
    　前記第２端部が、前記第５距離よりも長い第６距離だけ前記基準仮想平面から離間し、
    　前記シリンダの内壁の前記クランクケース側の端部が、前記第２端部から前記第１端部に近づくにつれて前記基準仮想平面に徐々に近づく形状を有する、
    　ように構成されてなる内燃機関。     The internal combustion engine according to claim 9,
    The cylinder inner wall is
    The first end is a plane including the axis of the crankshaft and is spaced by a fifth distance from a reference virtual plane that is a plane orthogonal to the axis of the cylinder;
    The second end is separated from the reference imaginary plane by a sixth distance longer than the fifth distance;
    The crankcase side end of the inner wall of the cylinder has a shape that gradually approaches the reference virtual plane as it approaches the first end from the second end.
    An internal combustion engine configured as described above.
  11. 　請求項９に記載の内燃機関において、
    　前記シリンダ内壁部は、
    　前記シリンダの内壁の前記クランクケース側の端部が、
    　前記クランクシャフトの軸線を含む平面であって前記シリンダの軸線と直交する平面である基準仮想平面と平行であり、且つ、
    　前記第１端部を含む第１領域を除く部分に前記シリンダの内壁から前記シリンダの軸線方向に延びる庇部を備える、
    　ように構成されてなる内燃機関。     The internal combustion engine according to claim 9,
    The cylinder inner wall is
    An end of the inner wall of the cylinder on the crankcase side is
    A plane including the axis of the crankshaft and parallel to a reference virtual plane which is a plane orthogonal to the axis of the cylinder, and
    A portion excluding the first region including the first end includes a flange extending from the inner wall of the cylinder in the axial direction of the cylinder.
    An internal combustion engine configured as described above.
  12. 　請求項８に記載の内燃機関において、
    　前記シリンダ内壁部は、前記シリンダの内壁から前記シリンダの内部に向けて突出する凸状部であって前記掻き落とされる潤滑油を前記第１端部及び前記第２端部のうち前記第１端部のみに向けて集中させるように前記シリンダの内壁に沿って連続的に延在する凸状部を備えるように構成されてなる内燃機関。     The internal combustion engine according to claim 8,
    The cylinder inner wall portion is a convex portion projecting from the inner wall of the cylinder toward the inside of the cylinder, and the lubricating oil to be scraped off is the first end of the first end and the second end. An internal combustion engine configured to include a convex portion that continuously extends along the inner wall of the cylinder so as to be concentrated toward only the portion.
  13. 　請求項８に記載の内燃機関において、
    　前記シリンダ内壁部は、前記シリンダ内壁に設けられた凹状部であって前記掻き落とされる潤滑油を前記第１端部及び前記第２端部のうち前記第１端部のみに向けて集中させるように前記シリンダの内壁に沿って連続的に延在する凹状部を備えるように構成されてなる内燃機関。     The internal combustion engine according to claim 8,
    The cylinder inner wall portion is a concave portion provided on the cylinder inner wall and concentrates the scraped lubricating oil toward only the first end portion of the first end portion and the second end portion. An internal combustion engine configured to include a concave portion that continuously extends along the inner wall of the cylinder.
  14. 　請求項１乃至請求項１３の何れか一項に記載の内燃機関であって、
    　前記吸気通路に設けられたコンプレッサと前記機関の排気通路に設けられたタービンとを含むターボチャージャを備え、
    　前記ブローバイガス還流装置は前記クランクケース内のブローバイガスを前記機関の吸気通路であって前記コンプレッサの上流へと流入させるように構成された内燃機関。     An internal combustion engine according to any one of claims 1 to 13,
    A turbocharger including a compressor provided in the intake passage and a turbine provided in an exhaust passage of the engine;
    The blow-by gas recirculation device is an internal combustion engine configured to cause blow-by gas in the crankcase to flow into an intake passage of the engine and upstream of the compressor.
PCT/JP2012/076632 2012-10-15 2012-10-15 Internal combustion engine equipped with blow-by gas recirculation device WO2014061086A1 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102022100000A1 (en) 2022-01-03 2023-07-06 Ford Global Technologies Llc diesel engine

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0791312A (en) * 1993-09-24 1995-04-04 Honda Motor Co Ltd Siamese type cylinder block and casting method thereof
JP2008025369A (en) * 2006-07-18 2008-02-07 Toyota Motor Corp Oil recovering unit
JP2011214446A (en) * 2010-03-31 2011-10-27 Nippon Soken Inc Internal combustion engine

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0791312A (en) * 1993-09-24 1995-04-04 Honda Motor Co Ltd Siamese type cylinder block and casting method thereof
JP2008025369A (en) * 2006-07-18 2008-02-07 Toyota Motor Corp Oil recovering unit
JP2011214446A (en) * 2010-03-31 2011-10-27 Nippon Soken Inc Internal combustion engine

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102022100000A1 (en) 2022-01-03 2023-07-06 Ford Global Technologies Llc diesel engine

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