EP1380729A1 - Dekompressionsanordnung für Brennkraftmaschine - Google Patents

Dekompressionsanordnung für Brennkraftmaschine Download PDF

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Publication number
EP1380729A1
EP1380729A1 EP03015089A EP03015089A EP1380729A1 EP 1380729 A1 EP1380729 A1 EP 1380729A1 EP 03015089 A EP03015089 A EP 03015089A EP 03015089 A EP03015089 A EP 03015089A EP 1380729 A1 EP1380729 A1 EP 1380729A1
Authority
EP
European Patent Office
Prior art keywords
flyweight
cam member
camshaft
cam
internal combustion
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP03015089A
Other languages
English (en)
French (fr)
Inventor
Giuseppe Ghelfi
Luciano Golzio
Stefano Albanello
Giovanni Arisio
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Tecumseh Products Co
Original Assignee
Tecumseh Products Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Tecumseh Products Co filed Critical Tecumseh Products Co
Publication of EP1380729A1 publication Critical patent/EP1380729A1/de
Withdrawn legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
    • F02N19/00—Starting aids for combustion engines, not otherwise provided for
    • F02N19/004—Aiding engine start by using decompression means or variable valve actuation
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L13/00—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations
    • F01L13/08—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for decompression, e.g. during starting; for changing compression ratio
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
    • F01L13/00—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations
    • F01L13/08—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for decompression, e.g. during starting; for changing compression ratio
    • F01L13/085—Modifications of valve-gear to facilitate reversing, braking, starting, changing compression ratio, or other specific operations for decompression, e.g. during starting; for changing compression ratio the valve-gear having an auxiliary cam protruding from the main cam profile

Definitions

  • the present invention relates to compression release mechanisms for small internal combustion engines of the type used in a variety of applications, such as lawnmowers, generators, pumps, tillers, pressure washers and other lawn and garden implements, or in small utility vehicles such as riding lawnmowers, lawn tractors, and the like.
  • the intake and exhaust valves of small internal combustion engines are actuated directly by a camshaft located in the cylinder head, or indirectly through the use of rocker arms, tappets, or other similar means.
  • the crankshaft drives a camshaft which is parallel to the crankshaft and located in the crankcase, and lobes on the camshaft actuate push rods and rocker arms to open and close the valves.
  • One type of overhead cam engine, in which a camshaft in the cylinder head directly actuates the valves is discussed in U.S. Patent No. 6,295,959, assigned to the assignee of the present invention, the disclosure of which is expressly incorporated herein by reference.
  • Compression release mechanisms for small internal combustion engines are usually operable at cranking speeds to prevent the exhaust valve from fully closing as the piston reaches its top dead center position, thereby allowing venting of pressure from the combustion chamber. In this manner, cranking of the engine is much easier and requires less force to be exerted by the operator.
  • the compression release mechanism is automatically rendered inoperative, such that the exhaust valve fully seats or closes as the piston approaches its top dead center position to allow combustion to proceed in a conventional manner.
  • a problem in many known compression release devices is that such devices incorporate a large number of parts, and are often mechanically complex. Further, such devices typically take up an undesirably large amount of space around the camshaft of the engine.
  • the present invention provides a compression release device for a small internal combustion engine, including a flyweight operatively coupled to a cam member via a cam pivot shaft, wherein a lever arm associated with the flyweight is longer than a lever arm associated with the cam member, such that a relatively small component of pivotal movement of the flyweight is translated into a relatively large component of rotation of the cam member.
  • a spring biases the flyweight to a first position, such that a cam surface of the cam member extends beyond the base circle of the exhaust cam lobe to partially open the exhaust valve and allow release of pressure within the combustion chamber of the engine.
  • the flyweight is moved under centrifugal force to a second position, rotating the cam member to a corresponding second position in which the cam surface is disposed within the base circle of the exhaust cam lobe, such that combustion may occur in a conventional manner.
  • the flyweight has a thin profile, reducing the overall size of the compression release device. Further, the construction of the compression release mechanism allows a relatively small pivotal movement of the flyweight to be transferred into a relatively large rotational movement of the cam member, thereby reducing the amount of space around the camshaft in which the flyweight must operate to actuate the compression release mechanism.
  • the body of the cam member is closely received for rotation within a recess in a support hub of the camshaft, such that forces from the contact between the cam surface of the cam member and the exhaust valve are transferred directly through the cam member to the support hub, and are not transferred to the other moving parts of the compression release mechanism, thereby increasing the operational life of the compression release mechanism.
  • a pivot shaft of the cam member is closely received within a slot of the flyweight such that, in each of the first and second positions of the flyweight, the pivot shaft is positively retained by the flyweight. Therefore, rotational movement of the cam member independent of corresponding pivotal movement of the flyweight is prevented, such that pivotal movement of the flyweight is accurately transferred to corresponding rotational movement of cam member.
  • the present invention provides an internal combustion engine, including a camshaft having at least one cam lobe, the cam lobe including a portion projecting beyond a base circle of the cam lobe for periodically engaging a valve; and a compression release mechanism, including a flyweight having a first end attached at a flyweight pivot to the camshaft, and a second end opposite the first end, the flyweight pivotally movable between first and second positions; a cam member rotatable with respect to the camshaft, the cam member having a body portion with an axis of rotation and a head portion eccentric to the body portion axis, the head portion coupled to the second end of the flyweight, wherein a first lever arm defined between the flyweight pivot and the head portion of the cam member is longer than a second lever arm defined between the body portion axis and the head portion of the cam member, such that a relatively small pivotal movement of the flyweight translates into a relatively large rotational movement of the cam member; and the cam member including a cam surface, the
  • the present invention provides an internal combustion engine, including a camshaft having at least one cam lobe, the cam lobe including a portion projecting beyond a base circle of the cam lobe for periodically engaging a valve; and a compression release mechanism, including a flyweight attached at a flyweight pivot to the camshaft for pivotal movement between first and second positions, the flyweight including an opening therein; a cam member rotatable with respect to the camshaft, the cam member having a body portion and a pivot shaft eccentric to the body portion and extending therefrom, the pivot shaft closely received within the flyweight opening, wherein a first lever arm defined between the flyweight pivot and the pivot shaft of the cam member is longer than a second lever arm defined between the body portion and the pivot shaft of the cam member, such that a relatively small pivotal movement of the flyweight translates into a relatively large rotational movement of the cam member; and the cam member including a cam surface, the cam surface projecting outwardly of the base circle when the flyweight is in the first position to
  • Fig. 1 is a perspective cutaway view of an overhead cam engine, showing the crankshaft, timing shaft with timing gear and timing pulley, timing belt, camshaft and camshaft pulley, with the crankcase, cylinder block and cylinder head partially shown;
  • Fig. 2 is a longitudinal sectional view of the engine of Fig. 1;
  • Fig. 3 is an elevational, partially cut away view of the camshaft, showing the compression release mechanism of the present invention in a first operational position in which the exhaust valve is partially opened;
  • Fig. 4 is a elevational, partially cut away view of the camshaft, showing the compression release mechanism of Fig. 3 in a second operational position in which the exhaust valve is allowed to fully close;
  • Fig. 5A is a perspective, exploded view of the compression release mechanism of Figs. 3 and 4;
  • Fig. 5B is a top view of the flyweight of the compression release mechanism of Fig. 5A viewed along line 5B-5B of Fig. 5A;
  • Fig. 6 is an end view of the compression release mechanism in the first operational position of Fig. 3;
  • Fig. 7 is an end view of the compression release mechanism in the second operational position of Fig. 4.
  • FIGs. 1 and 2 part of the drive train 10 of an overhead cam (“OHC”) engine, which can be either a vertical crankshaft or horizontal crankshaft engine, is shown.
  • OOC overhead cam
  • the engine is described in further detail in the above-incorporated U.S. Patent No. 6,295,959.
  • the present compression release mechanism 70 described further below, may be used with such overhead cam engines, or alternatively, may also be used in other types of small internal combustion engines, such as overhead valve (“OHV”) engines and side valve or L-head engines.
  • OCV overhead valve
  • L-head engines side valve or L-head engines.
  • crankcase 8 generally comprises crankcase base 14 and crankcase upper casing 12, where the upper portion of casing 12 defines a first side 12a of crankcase 8, and the lower portion of casing 12 and crankcase base 14 defines a second side 12b of crankcase 8 opposite the first side of crankcase 8.
  • Crankcase casing 12 includes upper crankshaft bearing 20 and upper timing shaft bearing 24.
  • Crankcase base 14 includes lower crankshaft bearing 22, lower timing shaft bearing 26, mounting flange 23, and oil sump 28.
  • Crankcase casing 12 and crankcase base 14 are attached to one another in a conventional manner.
  • crankshaft 32 Journals 32a and 32b of crankshaft 32 are rotatably carried in upper and lower crankshaft bearings 20 and 22, respectively, and crankshaft 32 is disposed along an axis L 1- L 1 .
  • Piston 25 (Fig. 2) is slidably received in cylinder bore 15 within cylinder block 16 along axis L 2 -L 2 perpendicular to crankshaft axis L 1 -L 1 .
  • Cylinder block 16 has integral supports 43 for mounting an electric ignition module (not shown) thereon, and integral cooling fins 34 for dissipating heat.
  • connecting rod 37 is rotatably connected to piston 25 by wrist pin 39, and is also rotatably connected to crankshaft 32 between throws 36 in a conventional manner.
  • Drive gear 38 secured to crankshaft 32 between upper and lower crankshaft bearings 20 and 22 and disposed in the second or lower side 12b of crankcase 8, is driven by crankshaft 32, and drive gear 38 drives timing gear 40, which is twice the diameter of drive gear 38.
  • Timing gear 40 is secured to timing shaft 42, which is rotatably carried in upper and lower timing shaft bearings 24 and 26, respectively, and extends substantially completely across crankcase 8.
  • Timing gear 40 is disposed in the lower side of crankcase 8. Therefore, crankshaft 32 is directly rotatably coupled to timing shaft 42, via drive gear 38 and timing gear 40, at a location in crankcase base 14, and crankshaft 32 drives timing shaft 42 at half the speed of crankshaft 32 through a gear set including drive gear 38 and timing gear 40.
  • Timing shaft 42 is disposed parallel to crankshaft axis L 1 -L 1 , and extends externally out of crankcase first or upper side 12a at one end, on which is secured a drive member in the form of toothed timing shaft pulley 44 held in place by snap ring 45 (Fig. 2).
  • Timing shaft pulley 44 drives toothed timing belt 46 and toothed camshaft pulley 48 (Fig. 2) which is secured to an end of camshaft 50 which extends externally of cylinder head 18.
  • Belt guard 52 substantially covers timing belt 46, and is fixed to cylinder head 18 and crankcase casing 12. As shown in Fig. 1, a portion of timing belt 46 around timing shaft pulley 44 is not covered by belt guard 52 but rather is exposed.
  • Camshaft 50 is carried in upper and lower camshaft bearings 54 and 56, respectively, within cylinder head 18, and is disposed along an axis substantially parallel to crankshaft axis L 1 -L 1 .
  • Camshaft 50 has spaced intake and exhaust cam lobes 58a, 58b, which periodically actuate tappets 60 as camshaft 50 rotates.
  • Tappets 60 are connected to intake and exhaust valves 62a, 62b extending through valve guides 64 within the cylinder head 18. Valves 62a, 62b seat against valve seats 66 which are press-fitted into cylinder head 18.
  • crankshaft 32 drives timing gear 40 at half crankshaft speed, which in turn drives timing shaft 42, timing pulley 44, timing belt 46, camshaft pulley 48, and camshaft 50 at a rotational speed equal to timing gear 40.
  • Rotational camshaft 50 rotates intake and exhaust lobes 58a, 58b, which engage tappets 60 to actuate intake and exhaust valves 62a, 62b in a conventional manner.
  • Camshaft 50 includes support hub 72 disposed adjacent exhaust lobe 58b, and support hub includes curved recess 74. Disposed adjacent support hub 72 is collar 76, which includes cam member hole 78 therethrough in alignment with recess 74, and which also includes pivot shaft aperture 80 and spring aperture 82. Support hub 84 is disposed adjacent collar 76, and includes stop ridge 86 projecting therefrom. Exhaust lobe 58b, support hub 72, collar 76, and support hub 84 may each comprise separate pieces secured individually to camshaft 50. Alternatively, each of the foregoing components may be integrally formed into a single component such as a rigid plastic, for example, which is secured to camshaft 50 in a suitable manner.
  • Cam member 90 generally includes body portion 92 and head portion 94.
  • Body portion 92 includes cam surface 96 and flat surface 98
  • head 94 includes cam pivot shaft 100 extending therefrom.
  • the longitudinal axis A 2 of cam pivot shaft 100 is spaced from, and therefore is eccentric with respect to, the longitudinal axis A 1 of body portion 92 of cam member 90.
  • Flyweight 102 is curved in shape to generally complement the outer surface of camshaft 50, and includes first end 102a disposed proximate a first side of camshaft 50, and second end 102b opposite first end 102a which is disposed proximate a second side of camshaft 50.
  • First end 102a of flyweight 102 includes pivot shaft aperture 104 for receipt of flyweight pivot shaft 106 therein.
  • Flyweight pivot shaft 106 is also received within pivot shaft aperture 80 in collar 76 to pivotally attach flyweight 102 to collar 76.
  • flyweight pivot shaft 106 may be integrally formed with either flyweight 102 or collar 76.
  • Flyweight 102 includes first side 103a which is disposed along a plane which is perpendicular to camshaft 50, and second side 103b opposite first side 103a which, as shown in Fig. 5B, is disposed along a plane which is slightly oblique with respect to camshaft 50. In this manner, the thickness of flyweight 102 decreases, or tapers, from a maximum thickness at first end 102a of flyweight 102 to a minimum thickness at second end 102b of flyweight 102. With further reference to Fig. 3, a clearance area 105 is defined between second end 102b of flyweight 102 and collar 76.
  • flyweight 102 When cam member 90 is inserted through cam member hole 78 of collar 76, head portion 94 of cam member 90 is disposed within clearance area 105, and cam pivot shaft 100 of cam member 90 is closely received within open-ended slot 110 in flyweight 102.
  • Flyweight 102 further includes finger 116 for engaging stop ridge 86 to limit the extent of rotational movement of flyweight 102 with respect to support hub 84, as described below.
  • Spring 112 includes opposite ends which are respectively received within spring aperture 114 in flyweight 102 and within spring aperture 82 of collar 76. Washer 118 is received about camshaft 50, and with reference to Fig. 2, it may be seen that washer 118 is sandwiched between flyweight 102 and camshaft bearing 54.
  • compression release mechanism 70 is disposed on camshaft 50 adjacent exhaust cam lobe 58b such that compression release mechanism 70 acts upon exhaust valve 62b to vent pressure from the combustion chamber of engine 10 at cranking speeds.
  • compression release mechanism 70 may also be disposed on camshaft 50 adjacent intake cam lobe 58a such that compression release mechanism 70 acts upon intake valve 62a to vent pressure from the combustion chamber of engine 10 at cranking speeds.
  • crankshaft 32 of the engine may be more easily rotated by an operator through the recoil starter mechanism of the engine (not shown), for example, to ease engine starting.
  • flyweight 102 due to the increased speed of rotation of camshaft 50 causes flyweight 102 to rotate upon flyweight pivot shaft 106 outwardly of support hub 84, overcoming the bias of spring 112, until finger 116 of flyweight 102 engages stop ridge 86 to limit the extent of outward movement of flyweight 102.
  • the foregoing rotation of flyweight 102 also rotationally translates cam pivot shaft 100 of cam member 90 within slot 110 of flyweight 102, thereby rotating cam member 90 such that flat 98 of cam 90 is exposed to tappet 60 of exhaust valve 62b and cam surface of cam member 90 is rotated within recess 74 of support hub 72.
  • flyweight 102 has a thin overall profile, and further, flyweight 102 has a particularly thin profile at second end 102b thereof, such that clearance area 105 is provided between flyweight 102 and collar 76 in which head portion 94 of cam member 90 is received, thereby reducing the overall width of compression release mechanism 70.
  • body portion 92 of cam member 90 is closely supported for rotation within recess 74 of support hub 72. Therefore, in the first operational position of compression release mechanism 70 shown in Fig.
  • pivot shaft 100 of cam member 90 is closely received within slot 110 of flyweight 102 such that, in each of the first and second positions of flyweight 102 shown in Figs. 6 and 7, respectively, pivot shaft 100 is positively retained by flyweight 102 in the positions which are shown in Figs. 6 and 7. Therefore, rotational movement of cam member 90 independent of corresponding pivotal movement of flyweight 102 is prevented, and pivotal movement of flyweight 102 is accurately and precisely transferred to corresponding rotational movement of cam member 90.
  • a relatively small component of rotational movement of flyweight 102 is transferred into a relatively large component of rotational movement of body portion 92 of cam member 90.
  • a first lever arm LA 1 -LA 1 associated with flyweight 102 is much longer than a second lever arm LA 2 -LA 2 associated with cam member 90, as defined between cam pivot shaft 100 and the longitudinal axis A 1 of body portion 92 of cam member 90.
  • Figs. 6 and 7 it may be seen that a relatively small component of rotational movement of flyweight 102 is transferred into a relatively large component of rotational movement of body portion 92 of cam member 90.
  • the ratio of the length of the first lever arm to the length of the second lever arm is about 8:1; however, such ratio may be from about 10:1 to about 3:1 to enable a relatively small pivotal movement of flyweight 102 to translate into a relatively large rotational movement of cam member 90.
  • flyweight 102 moves from its first operational position (Fig. 6) to its second operational position (Fig. 7), cam pivot shaft 100 rotationally translates within slot 110 of flyweight 102. Further, flyweight 102 rotates through a relatively small angle ⁇ , defined between the first and second positions of lever arm LA 1 -LA 1 , which may be about 5-10° for example, whereas cam member 90 rotates through a much greater angle of up to about 90°. Therefore, the overall extent of movement of flyweight 102 is minimized during operation of compression release mechanism 70, conserving space within the cylinder head of the engine.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Valve Device For Special Equipments (AREA)
  • Valve-Gear Or Valve Arrangements (AREA)
EP03015089A 2002-07-08 2003-07-03 Dekompressionsanordnung für Brennkraftmaschine Withdrawn EP1380729A1 (de)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US39444502P 2002-07-08 2002-07-08
US394445P 2002-07-08
US10/328,290 US20040003791A1 (en) 2002-07-08 2002-12-23 Compression release mechanism
US328290 2002-12-23

Publications (1)

Publication Number Publication Date
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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1557542A1 (de) * 2004-01-22 2005-07-27 Yamaha Hatsudoki Kabushiki Kaisha Brennkraftmaschine mit federbelasteter Dekompressionsanordnung
EP1892388A1 (de) 2006-08-08 2008-02-27 HONDA MOTOR CO., Ltd. Motor mit Dekompressionsvorrichtung
EP1995417A1 (de) * 2007-05-22 2008-11-26 Mahle International GmbH Nockenwelle
TWI451031B (zh) * 2010-05-12 2014-09-01 Sanyang Industry Co Ltd Engine decompression mechanism
EP2949888A3 (de) * 2014-05-27 2016-01-27 Yamaha Hatsudoki Kabushiki Kaisha Motor und fahrzeug
EP2949890A3 (de) * 2014-05-27 2016-02-24 Yamaha Hatsudoki Kabushiki Kaisha Motor und fahrzeug
TWI611094B (zh) * 2014-05-27 2018-01-11 山葉發動機股份有限公司 引擎及車輛
CN107575274A (zh) * 2016-07-05 2018-01-12 铃木株式会社 可变气门机构、发动机和自动二轮车
CN112384683A (zh) * 2018-07-05 2021-02-19 本田技研工业株式会社 发动机的减压装置及发动机

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WO2005019634A2 (en) * 2003-08-20 2005-03-03 Kohler Co. Automatic compression release mechanism including feature to prevent unintentional disablement during engine shutdown
US8210008B2 (en) * 2008-08-08 2012-07-03 Lear Corporation Ignition module with multi-beam spring
CN101881198A (zh) * 2010-03-09 2010-11-10 于宥源 一种发动机变功率配气控制***
US20150198083A1 (en) * 2014-01-14 2015-07-16 Electro-Motive Diesel Inc. Dual-fuel engine having extended valve opening
JP6386290B2 (ja) * 2014-08-13 2018-09-05 株式会社工進 エンジンのデコンプ装置
JP6378988B2 (ja) * 2014-09-22 2018-08-22 株式会社オティックス 内燃機関の可変動弁機構
US9581187B2 (en) * 2015-06-05 2017-02-28 Achates Power, Inc. Minimizing oil leakage from rocking journal bearings of two-stroke cycle engines
JP6673986B2 (ja) * 2018-07-18 2020-04-01 本田技研工業株式会社 内燃機関
JP7286940B2 (ja) * 2018-10-19 2023-06-06 スズキ株式会社 動弁機構

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US4898133A (en) * 1988-12-07 1990-02-06 Kohler Co. Automatic compression release apparatus for an internal combustion engine
EP0407699A1 (de) * 1989-07-12 1991-01-16 Tecumseh Products Company Mechanische Dekompressionsvorrichtung
US5197422A (en) * 1992-03-19 1993-03-30 Briggs & Stratton Corporation Compression release mechanism and method for assembling same
EP1101903A1 (de) * 1999-11-17 2001-05-23 Tecumseh Products Company Mechanische Dekompressionsvorrichtung
US6295959B1 (en) * 1999-03-19 2001-10-02 Tecumseh Products Company External drive double shaft overhead cam engine
US6394054B1 (en) * 2001-01-15 2002-05-28 Tecumseh Products Company Mechanical compression and vacuum release

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US4898133A (en) * 1988-12-07 1990-02-06 Kohler Co. Automatic compression release apparatus for an internal combustion engine
EP0407699A1 (de) * 1989-07-12 1991-01-16 Tecumseh Products Company Mechanische Dekompressionsvorrichtung
US5197422A (en) * 1992-03-19 1993-03-30 Briggs & Stratton Corporation Compression release mechanism and method for assembling same
US6295959B1 (en) * 1999-03-19 2001-10-02 Tecumseh Products Company External drive double shaft overhead cam engine
EP1101903A1 (de) * 1999-11-17 2001-05-23 Tecumseh Products Company Mechanische Dekompressionsvorrichtung
US6394054B1 (en) * 2001-01-15 2002-05-28 Tecumseh Products Company Mechanical compression and vacuum release

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1557542A1 (de) * 2004-01-22 2005-07-27 Yamaha Hatsudoki Kabushiki Kaisha Brennkraftmaschine mit federbelasteter Dekompressionsanordnung
US7137375B2 (en) 2004-01-22 2006-11-21 Yamaha Motor Co., Ltd. Decompression mechanism for engine
EP1892388A1 (de) 2006-08-08 2008-02-27 HONDA MOTOR CO., Ltd. Motor mit Dekompressionsvorrichtung
US7726271B2 (en) 2006-08-08 2010-06-01 Honda Motor Co., Ltd. Engine with decompression device
CN101122247B (zh) * 2006-08-08 2010-10-27 本田技研工业株式会社 具备减压装置的发动机
EP1995417A1 (de) * 2007-05-22 2008-11-26 Mahle International GmbH Nockenwelle
US8720055B2 (en) 2007-05-22 2014-05-13 Mahle International Gmbh Method of assembling a cam shaft that includes a thermal interference fit between the cam shaft and a bearing
TWI451031B (zh) * 2010-05-12 2014-09-01 Sanyang Industry Co Ltd Engine decompression mechanism
EP2949888A3 (de) * 2014-05-27 2016-01-27 Yamaha Hatsudoki Kabushiki Kaisha Motor und fahrzeug
CN105317500A (zh) * 2014-05-27 2016-02-10 雅马哈发动机株式会社 发动机以及车辆
EP2949890A3 (de) * 2014-05-27 2016-02-24 Yamaha Hatsudoki Kabushiki Kaisha Motor und fahrzeug
CN105317500B (zh) * 2014-05-27 2017-11-03 雅马哈发动机株式会社 发动机以及车辆
TWI611095B (zh) * 2014-05-27 2018-01-11 山葉發動機股份有限公司 引擎及車輛
TWI611094B (zh) * 2014-05-27 2018-01-11 山葉發動機股份有限公司 引擎及車輛
CN107575274A (zh) * 2016-07-05 2018-01-12 铃木株式会社 可变气门机构、发动机和自动二轮车
CN107575274B (zh) * 2016-07-05 2020-02-07 铃木株式会社 可变气门机构、发动机和自动二轮车
CN112384683A (zh) * 2018-07-05 2021-02-19 本田技研工业株式会社 发动机的减压装置及发动机
EP3800333A4 (de) * 2018-07-05 2021-06-09 Honda Motor Co., Ltd. Motorsteuerungsvorrichtung und motor
US11384725B2 (en) 2018-07-05 2022-07-12 Honda Motor Co., Ltd. Engine decompression device and engine

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