WO2012028507A1 - Pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine and associated assembly method - Google Patents

Pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine and associated assembly method Download PDF

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Publication number
WO2012028507A1
WO2012028507A1 PCT/EP2011/064537 EP2011064537W WO2012028507A1 WO 2012028507 A1 WO2012028507 A1 WO 2012028507A1 EP 2011064537 W EP2011064537 W EP 2011064537W WO 2012028507 A1 WO2012028507 A1 WO 2012028507A1
Authority
WO
WIPO (PCT)
Prior art keywords
piston
seat
support plate
pump unit
diameter
Prior art date
Application number
PCT/EP2011/064537
Other languages
French (fr)
Inventor
Gaetano Riglietti
Original Assignee
Robert Bosch Gmbh
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 Robert Bosch Gmbh filed Critical Robert Bosch Gmbh
Priority to EP11746265.5A priority Critical patent/EP2612017B1/en
Priority to CN201180040979.XA priority patent/CN103080530B/en
Priority to JP2013526410A priority patent/JP5654682B2/en
Priority to RU2013114165/06A priority patent/RU2573434C2/en
Priority to KR1020137005394A priority patent/KR20130103718A/en
Publication of WO2012028507A1 publication Critical patent/WO2012028507A1/en

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M59/00—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps
    • F02M59/02—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps of reciprocating-piston or reciprocating-cylinder type
    • F02M59/10—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps of reciprocating-piston or reciprocating-cylinder type characterised by the piston-drive
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M59/00—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps
    • F02M59/44—Details, components parts, or accessories not provided for in, or of interest apart from, the apparatus of groups F02M59/02 - F02M59/42; Pumps having transducers, e.g. to measure displacement of pump rack or piston
    • F02M59/48—Assembling; Disassembling; Replacing
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
    • F04B1/04—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
    • F04B1/04—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement
    • F04B1/0404—Details or component parts
    • F04B1/0408—Pistons
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
    • F04B1/04—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement
    • F04B1/0404—Details or component parts
    • F04B1/0426—Arrangements for pressing the pistons against the actuated cam; Arrangements for connecting the pistons to the actuated cam
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B53/00—Component parts, details or accessories not provided for in, or of interest apart from, groups F04B1/00 - F04B23/00 or F04B39/00 - F04B47/00
    • F04B53/14—Pistons, piston-rods or piston-rod connections

Definitions

  • the present invention relates to a pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine.
  • the present invention relates to a pump unit comprising a pump body; a piston pump designed to feed the fuel to an internal combustion engine; and a gear pump designed to feed the fuel to the piston pump.
  • the piston pump comprises at least one cylinder which is formed in the pump body; and a piston engaged slidably inside the cylinder so as to perform an intake stroke for drawing the fuel into the cylinder under the thrust of a spring arranged between the pump body and a support plate mounted on the piston and a compression stroke for compressing the fuel contained inside the cylinder under the thrust of an actuating device.
  • the support plate has an opening, which is formed through the support plate, parallel to a longitudinal axis of the piston, and comprises a seat for inserting the piston through the support plate, a seat for engaging the piston in the support plate, and a communicating section for allowing the piston to pass between the insertion seat and the engaging seat.
  • the piston is provided with an annular groove, which is formed on the outer surface of the piston and has a diameter slightly greater than a width of the communicating section; the insertion seat has a substantially circular shape and a diameter slightly greater than a diameter of the piston; and the engaging seat has a substantially circular shape and a diameter slightly greater than the diameter of the annular groove.
  • the known pump units of the type described above have a number of drawbacks due principally to the fact that assembly of the support plate on the piston may cause damage to the annular groove, separation of metal particles from the piston and, therefore, reduction of the fatigue strength of the piston and seizing of the piston inside the cylinder.
  • the object of the present invention is to provide a pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine, which does not have the drawbacks described above and which is simple and inexpensive to produce.
  • a pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine as claimed in Claims 1 to 12 is provided.
  • the present invention also relates to a method for assembling a pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine.
  • a method for assembling a pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine as claimed in Claims 13 to 17 is provided.
  • Figure 1 is a schematic cross-sectional view, with parts removed for the sake of clarity, of a preferred embodiment of the pump unit according to the present invention
  • Figure 2 is a side view of a first detail of Figure 1; and Figure 3 is a plan view of a second detail of Figure 1.
  • 1 denotes, in its entirety, a pump unit for feeding fuel, in particular diesel fuel, to an internal combustion engine (not shown).
  • the pump unit 1 comprises a pump body 2 provided with a central hole (not shown) having a given longitudinal axis 3; a piston pump 4 designed to feed the fuel to the said internal combustion engine (not shown); and a gear pump, known and not shown, designed to feed the fuel to the pump 4.
  • the pump 4 comprises a plurality of cylinders 5 (only one of which is shown in Figure 1) which are formed in the pump body 2, are uniformly distributed around the axis 3 and have respective longitudinal axes 6 substantially perpendicular to the axis 3.
  • Each cylinder 5 is slidably engaged by an associated piston 7 which is mounted inside the cylinder 5 coaxially with the axis 6, has a diameter Dl and is provided with an annular groove 8 (Figure 2) which is formed on an outer surface of the piston 7 at an intermediate point of the piston 7 itself and has a diameter D2 smaller than the diameter Dl.
  • the pistons 7 are displaced with an alternating rectilinear movement along the associated cylinders 5 by an actuating device 9 comprising, in the case in question, a drive shaft (not shown) which extends through the pump body 2 coaxially with the axis 3, is mounted so as to rotate, relative to the pump body 2, about the axis 3 and has an eccentric portion engaged rotatably, via a rolling bearing (not shown), through a sleeve (not shown).
  • actuating device 9 comprising, in the case in question, a drive shaft (not shown) which extends through the pump body 2 coaxially with the axis 3, is mounted so as to rotate, relative to the pump body 2, about the axis 3 and has an eccentric portion engaged rotatably, via a rolling bearing (not shown), through a sleeve (not shown).
  • the sleeve (not shown) has a longitudinal axis parallel to the axis 3 and is bounded externally by a cylindrical surface provided with a plurality of flat faces equal in number to the number of cylinders 5 and each facing a respective disk element (not shown) arranged between an associated piston 7 and the flat face itself.
  • the actuating device 9 furthermore comprises, for each piston 7, a respective spring 10 which is mounted coaxially with the associated axis 6, is arranged between the pump body 2 and a substantially flat support plate 11 mounted on the piston 7, perpendicularly with respect to the associated axis 6, and is designed to displace - and normally keep - the piston 7 itself in contact with the associated disk element (not shown).
  • each piston 7 is displaced by the associated spring 10 during an outward intake stroke for drawing the fuel into the associated cylinder 5 and by the eccentric portion of the drive shaft (not shown), by the sleeve (not shown) and by the associated washer (not shown) during a return compression stroke for compressing the fuel contained inside the said associated cylinder 5.
  • the plate 11 has an opening 12 which is formed through the plate 11, parallel to the axis 6, has a plane S of symmetry substantially coplanar with the axis 6, is bounded by a shaped side wall 13 and comprises a seat 14 for inserting the piston 7 through the plate 11, a seat 15 for engaging the piston 7 in the plate 11, and a communicating section 16 allowing passage between the seat 14 and the seat 15.
  • the seat 14 has a substantially circular shape, a centre CI of curvature different from the axis 6, and a diameter D3 slightly greater than the diameter Dl of the piston 7; and the seat 15 has a substantially circular shape, a centre C2 of curvature substantially arranged along the axis 6, and a diameter D4 which is slightly smaller than the diameter Dl of the piston 7 and slightly greater than the diameter D2 of the groove 8. It should be pointed out, moreover, that the distance between the centres CI and C2 is smaller than the sum of the radii of curvature of the two seats 14 and 15.
  • the communicating section 16 is bounded laterally by two elastically deformable arms 17 which project from the wall 13 inside the opening 12, extend on opposite sides of the plane S and have respective free ends 18 provided, in the case in question, with respective holes 19 formed in the plate 11, parallel to the axis 6.
  • the arms 17 are arranged, normally, in an initial narrow configuration ( Figure 3) where the section 16 has a width LI, measured perpendicularly with respect to the plane S, which is slightly smaller than the diameter D2 of the groove 8 and where each arm 17 has a substantially V-shaped form and cooperates with the other arm 17 so as to define part of the seat 14 and part of the seat 15.
  • the opening 12 further comprises two recesses 20, which are formed on opposite sides of the plane S and are each bounded by the wall 13 and by an associ ated arm 17.
  • the piston 7 is inserted into the insertion seat 14; the plate 11 is displaced axially along the piston 7 so as to align radially the groove 8 with the communicating section 16; the arms 17 are splayed inside the associated recesses 20, for example by means of a splaying tool (not shown) engaged inside the holes 19, so as to provide the section 16 with a final widened configuration (not shown), where the section 16 has a width L2, measured perpendicularly with respect to the plane S, greater than the width LI and at least equal to the diameter of the groove 8; the piston 7 is displaced radially from the seat 14 into the engaging seat 15 so as to move the groove 8 through the section 16; and the arms 17 are released so as to radially lock the piston 7 inside the seat 15.
  • the groove 8 has, in the case in question, a height H greater than the thickness of the plate 11, the plate 11 is finally displaced axially in contact with the piston 7.
  • the final widened configuration of the arms 17 allows the piston 7 to be displaced radially from the seat 14 into the seat 15 without interfering with the section 16 and therefore avoids damage to the groove 8, separation of metal particles from the piston 7, reduction in the fatigue strength of the piston 7 and seizing of the piston 7 inside the cylinder 5.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Fuel-Injection Apparatus (AREA)
  • Output Control And Ontrol Of Special Type Engine (AREA)
  • Details Of Reciprocating Pumps (AREA)

Abstract

In order to draw fuel inside a cylinder (5) of a pump unit, a piston (7) is displaced along the cylinder (5) by a spring (10) arranged between a pump body (2) and a support plate (11), which is mounted on the piston (7), and has a seat (14) for inserting the piston (7) through the support plate (11), a seat (15) for engaging the piston (7) in the support plate (11), and a communicating section (16) for allowing the piston (7) to pass between the insertion seat (14) and the engaging seat (15); the communicating section (16) being bounded laterally by two elastically deformable arms (17) each having a respective free end (18).

Description

Description Title
PUMP UNIT FOR FEEDING FU EL, PREFERABLY DIESEL FU EL, TO AN INTERNAL COMBUSTION ENGIN E AND ASSOCIATED ASSEMBLY METHOD
The present invention relates to a pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine.
In particular, the present invention relates to a pump unit comprising a pump body; a piston pump designed to feed the fuel to an internal combustion engine; and a gear pump designed to feed the fuel to the piston pump.
The piston pump comprises at least one cylinder which is formed in the pump body; and a piston engaged slidably inside the cylinder so as to perform an intake stroke for drawing the fuel into the cylinder under the thrust of a spring arranged between the pump body and a support plate mounted on the piston and a compression stroke for compressing the fuel contained inside the cylinder under the thrust of an actuating device.
The support plate has an opening, which is formed through the support plate, parallel to a longitudinal axis of the piston, and comprises a seat for inserting the piston through the support plate, a seat for engaging the piston in the support plate, and a communicating section for allowing the piston to pass between the insertion seat and the engaging seat.
Generally, the piston is provided with an annular groove, which is formed on the outer surface of the piston and has a diameter slightly greater than a width of the communicating section; the insertion seat has a substantially circular shape and a diameter slightly greater than a diameter of the piston; and the engaging seat has a substantially circular shape and a diameter slightly greater than the diameter of the annular groove. Once the piston has been introduced into the insertion seat, the piston and the support plate are firstly displaced axially with respect to each other until the annular groove is radially aligned with the communicating section and are then displaced radially with respect to each other so as to transfer the piston from the insertion seat into the engaging seat by moving the annular groove through the communicating section.
Since the width of the communicating section is smaller than the diameter of the annular groove, the annular groove interferes with the communicating section when the piston is displaced from the insertion seat into the engaging seat. Consequently, the known pump units of the type described above have a number of drawbacks due principally to the fact that assembly of the support plate on the piston may cause damage to the annular groove, separation of metal particles from the piston and, therefore, reduction of the fatigue strength of the piston and seizing of the piston inside the cylinder.
The object of the present invention is to provide a pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine, which does not have the drawbacks described above and which is simple and inexpensive to produce.
According to the present invention a pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine as claimed in Claims 1 to 12 is provided.
The present invention also relates to a method for assembling a pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine.
According to the present invention a method for assembling a pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine as claimed in Claims 13 to 17 is provided.
The present invention will now be described with reference to the accompanying drawings which illustrate a non-limiting example of embodiment thereof in which: Figure 1 is a schematic cross-sectional view, with parts removed for the sake of clarity, of a preferred embodiment of the pump unit according to the present invention;
Figure 2 is a side view of a first detail of Figure 1; and Figure 3 is a plan view of a second detail of Figure 1.
With reference to Figure 1, 1 denotes, in its entirety, a pump unit for feeding fuel, in particular diesel fuel, to an internal combustion engine (not shown).
The pump unit 1 comprises a pump body 2 provided with a central hole (not shown) having a given longitudinal axis 3; a piston pump 4 designed to feed the fuel to the said internal combustion engine (not shown); and a gear pump, known and not shown, designed to feed the fuel to the pump 4.
The pump 4 comprises a plurality of cylinders 5 (only one of which is shown in Figure 1) which are formed in the pump body 2, are uniformly distributed around the axis 3 and have respective longitudinal axes 6 substantially perpendicular to the axis 3.
Each cylinder 5 is slidably engaged by an associated piston 7 which is mounted inside the cylinder 5 coaxially with the axis 6, has a diameter Dl and is provided with an annular groove 8 (Figure 2) which is formed on an outer surface of the piston 7 at an intermediate point of the piston 7 itself and has a diameter D2 smaller than the diameter Dl.
The pistons 7 are displaced with an alternating rectilinear movement along the associated cylinders 5 by an actuating device 9 comprising, in the case in question, a drive shaft (not shown) which extends through the pump body 2 coaxially with the axis 3, is mounted so as to rotate, relative to the pump body 2, about the axis 3 and has an eccentric portion engaged rotatably, via a rolling bearing (not shown), through a sleeve (not shown). The sleeve (not shown) has a longitudinal axis parallel to the axis 3 and is bounded externally by a cylindrical surface provided with a plurality of flat faces equal in number to the number of cylinders 5 and each facing a respective disk element (not shown) arranged between an associated piston 7 and the flat face itself.
The actuating device 9 furthermore comprises, for each piston 7, a respective spring 10 which is mounted coaxially with the associated axis 6, is arranged between the pump body 2 and a substantially flat support plate 11 mounted on the piston 7, perpendicularly with respect to the associated axis 6, and is designed to displace - and normally keep - the piston 7 itself in contact with the associated disk element (not shown).
Following rotation of the drive shaft (not shown), each piston 7 is displaced by the associated spring 10 during an outward intake stroke for drawing the fuel into the associated cylinder 5 and by the eccentric portion of the drive shaft (not shown), by the sleeve (not shown) and by the associated washer (not shown) during a return compression stroke for compressing the fuel contained inside the said associated cylinder 5.
In accordance with that shown in Figure 3, the plate 11 has an opening 12 which is formed through the plate 11, parallel to the axis 6, has a plane S of symmetry substantially coplanar with the axis 6, is bounded by a shaped side wall 13 and comprises a seat 14 for inserting the piston 7 through the plate 11, a seat 15 for engaging the piston 7 in the plate 11, and a communicating section 16 allowing passage between the seat 14 and the seat 15.
The seat 14 has a substantially circular shape, a centre CI of curvature different from the axis 6, and a diameter D3 slightly greater than the diameter Dl of the piston 7; and the seat 15 has a substantially circular shape, a centre C2 of curvature substantially arranged along the axis 6, and a diameter D4 which is slightly smaller than the diameter Dl of the piston 7 and slightly greater than the diameter D2 of the groove 8. It should be pointed out, moreover, that the distance between the centres CI and C2 is smaller than the sum of the radii of curvature of the two seats 14 and 15.
The communicating section 16 is bounded laterally by two elastically deformable arms 17 which project from the wall 13 inside the opening 12, extend on opposite sides of the plane S and have respective free ends 18 provided, in the case in question, with respective holes 19 formed in the plate 11, parallel to the axis 6.
The arms 17 are arranged, normally, in an initial narrow configuration (Figure 3) where the section 16 has a width LI, measured perpendicularly with respect to the plane S, which is slightly smaller than the diameter D2 of the groove 8 and where each arm 17 has a substantially V-shaped form and cooperates with the other arm 17 so as to define part of the seat 14 and part of the seat 15.
The opening 12 further comprises two recesses 20, which are formed on opposite sides of the plane S and are each bounded by the wall 13 and by an associ ated arm 17.
In order to assemble the plate 11 on the piston 7: the piston 7 is inserted into the insertion seat 14; the plate 11 is displaced axially along the piston 7 so as to align radially the groove 8 with the communicating section 16; the arms 17 are splayed inside the associated recesses 20, for example by means of a splaying tool (not shown) engaged inside the holes 19, so as to provide the section 16 with a final widened configuration (not shown), where the section 16 has a width L2, measured perpendicularly with respect to the plane S, greater than the width LI and at least equal to the diameter of the groove 8; the piston 7 is displaced radially from the seat 14 into the engaging seat 15 so as to move the groove 8 through the section 16; and the arms 17 are released so as to radially lock the piston 7 inside the seat 15.
Since the groove 8 has, in the case in question, a height H greater than the thickness of the plate 11, the plate 11 is finally displaced axially in contact with the piston 7.
The final widened configuration of the arms 17 allows the piston 7 to be displaced radially from the seat 14 into the seat 15 without interfering with the section 16 and therefore avoids damage to the groove 8, separation of metal particles from the piston 7, reduction in the fatigue strength of the piston 7 and seizing of the piston 7 inside the cylinder 5.

Claims

Claims
1. Pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine, the pump unit comprising a pump body (2); at least one cylinder (5) formed in the pump body (2); a piston (7), which is slidably engaged inside the cylinder (5) and has at least one first diameter (D2); a support plate (11) mounted on the piston (7); a spring (10) arranged between the pump body (2) and the support plate (11) for displacing the piston (7) during an intake stroke for drawing the fuel into the cylinder (5); and an actuating device for displacing the piston (7) during a compression stroke for compressing the fuel contained inside the said cylinder (5); the support plate (11) having an opening (12) which is formed through the support plate (11), parallel to a longitudinal axis (6) of the piston (7), and comprises a seat (14) for inserting the piston (7) through the support plate (11), a seat (15) for engaging the piston (7) in the support plate (11), and a communicating section (16) for allowing the piston (7) to pass between the insertion seat (14) and the engaging seat (15); the communicating section (16) having, in an initial narrow configuration thereof, a first width (LI) which is slightly smaller than the said first diameter (D2); and being characterized in that the communicating section (16) is bounded laterally by two elastically deformable arms (17) each having a respective free end (18).
2. Pump unit according to Claim 1, wherein the communicating section (16) has, in a final widened configuration thereof following widening of the two arms (17), a second width (L2) at least equal to the said first diameter (D2).
3. Pump unit according to Claim 2, wherein the arms (17) have respective gripping means (19) designed to allow displacement of the said arms (17) into the final widened configuration.
4. Pump unit according to Claim 2 or 3, wherein the arms (17) have respective gripping seats (19) designed to be engaged by at least one splaying tool for displacing the arms (17) into the final widened configuration.
5. Pump unit according to any one of the preceding claims, wherein the insertion seat (14) and the engaging seat (15) are substantially circular.
6. Pump unit according to Claim 5, wherein the centres of curvature (CI, C2) of the insertion and engaging seats (14, 15) are arranged at a distance from one another less than the sum of the radii of curvature of the said insertion and engaging seats (14, 15).
7. Pump unit according to any one of the preceding claims, wherein the said opening (12) has, furthermore, two recesses (20) arranged on opposite sides of the communicating section (16) for receiving the arms (17) following elastic deformation of the said arms (17).
8. Pump unit according to any one of the preceding claims, wherein the piston (7) has a second diameter (Dl) and comprises at least one annular groove (8) which is formed on the outer surface of the piston (7) and has the said first diameter (D2).
9. Pump unit according to Claim 8, wherein the insertion seat (14) has a third diameter (D3) slightly greater than the second diameter (Dl) and the engaging seat (15) has a fourth diameter (D4) slightly greater than the first diameter (D2) and slightly smaller than the second diameter (Dl).
10. Pump unit according to Claim 8 or 9, wherein the annular groove (8) has a height (H), measured parallel to the said axis (6), which is greater than a thickness of the support plate (11).
11. Pump unit according to any one of the preceding claims, wherein the two arms (17) project inside the opening (12) from a side wall (13) of the said opening (12).
12. Pump unit according to Claim 11, wherein, at least when the arms (17) are arranged in their initial narrow configuration, each arm (17) has a substan- tially V-shaped form and cooperates with the other arm (17) so as to define part of the insertion seat (14) and part of the engaging seat (15).
13. Method for assembling a pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine, the pump unit comprising a pump body (2); at least one cylinder (5) formed in the pump body (2); a piston (7), which is slidably engaged inside the cylinder (5), extends through a support plate (11) and has at least one first diameter (D2); a spring (10) arranged between the pump body (2) and the support plate (11) for displacing the piston (7) during an intake stroke for drawing the fuel into the cylinder (5); and an actuating device for displacing the piston (7) during a compression stroke for compressing the fuel contained inside the said cylinder (5); the support plate (11) having an opening (12), which is formed through the support plate (11), parallel to a longitudinal axis (6) of the piston (7), and comprises a seat (14) for inserting the piston (7) through the support plate (11), a seat (15) for engaging the piston (7) in the support plate (11), and a communicating section (16) for allowing the piston (7) to pass between the insertion seat (14) and the engaging seat (15); the communicating section (16) being bounded laterally by two elastically deformable arms (17) each having a respective free end (18) and having, in an initial narrow configuration thereof, a first width (LI) which is slightly smaller than the said first diameter (D2); the method comprising the steps of: introducing the piston (7) into the insertion seat (14); widening the two arms (17) so as to impart to the communicating section (16) a final widened configuration, where the communicating section (16) has a second width (L2) at least equal to the said first diameter (D2); and displacing the piston (7) and the support plate (11) with respect to each other transversely with respect to the said axis (6) so as to displace the piston (7) from the insertion seat (14) into the engaging seat (15) through the communicating section (16).
14. Method according to Claim 13, wherein the piston (7) is displaced from the insertion seat (14) into the engaging seat (15) without interfering with the communicating section (16).
15. Method according to Claim 13 or 14 and further comprising the step of: releasing the two arms (17) so as to radially lock the piston (7) inside the engaging seat (15).
16. Method according to any one of Claims 13 to 15, wherein the piston (7) has a second diameter (Dl) and comprises at least one annular groove (8) which is formed on the outer surface of the piston (7) and has the said first diameter (D2); the method further comprising the steps of: axially displacing the piston (7) and the support plate (11) with respect to each other through the insertion seat (14) so as to align the annular groove (8) with the communicating section (16); and radially displacing the piston (7) and the support plate (11) with respect to each other so as to move the annular groove (8) through the communicating section (16).
17. Method according to Claim 16, wherein the annular groove (8) is formed at an intermediate point of the piston (7) and has a height (H), measured parallel to the said axis (6), greater than a thickness of the support plate (11); the method further comprising the step of: axially displacing the piston (7) and the support plate (11) with respect to each other through the engaging seat (15) so as to lock axially the support plate (11) against the said piston (7).
PCT/EP2011/064537 2010-09-01 2011-08-24 Pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine and associated assembly method WO2012028507A1 (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
EP11746265.5A EP2612017B1 (en) 2010-09-01 2011-08-24 Pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine and associated assembly method
CN201180040979.XA CN103080530B (en) 2010-09-01 2011-08-24 The fuel being preferably diesel fuel is supplied to pump unit and the corresponding mounting method thereof of internal-combustion engine
JP2013526410A JP5654682B2 (en) 2010-09-01 2011-08-24 Fuel, preferably a pump unit for supplying diesel fuel to an internal combustion engine, and associated assembly method
RU2013114165/06A RU2573434C2 (en) 2010-09-01 2011-08-24 Pump assembly for diesel oil feed into ice and method of such pump assembly assemblage
KR1020137005394A KR20130103718A (en) 2010-09-01 2011-08-24 Pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine and associated assembly method

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ITMI2010A001594 2010-09-01
ITMI2010A001594A IT1401914B1 (en) 2010-09-01 2010-09-01 PUMPING UNIT FOR FUEL SUPPLEMENT, PREFERABLY GASOIL, TO AN INTERNAL COMBUSTION ENGINE AND RELATIVE ASSEMBLY METHOD

Publications (1)

Publication Number Publication Date
WO2012028507A1 true WO2012028507A1 (en) 2012-03-08

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PCT/EP2011/064537 WO2012028507A1 (en) 2010-09-01 2011-08-24 Pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine and associated assembly method

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EP (1) EP2612017B1 (en)
JP (1) JP5654682B2 (en)
KR (1) KR20130103718A (en)
CN (1) CN103080530B (en)
IT (1) IT1401914B1 (en)
RU (1) RU2573434C2 (en)
WO (1) WO2012028507A1 (en)

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Publication number Priority date Publication date Assignee Title
ITMI20131903A1 (en) * 2013-11-15 2015-05-16 Bosch Gmbh Robert HIGH PRESSURE PUMP FOR FUEL SUPPLY TO AN INTERNAL COMBUSTION ENGINE
US11466649B2 (en) * 2017-12-13 2022-10-11 Robert Bosch Gmbh Pumping unit for feeding fuel, preferably diesel fuel, to an internal combustion engine

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016055294A1 (en) * 2014-10-09 2016-04-14 Robert Bosch Gmbh Pump unit for supplying fuel, preferably diesel oil, to an internal combustion engine

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DE4310192A1 (en) * 1992-07-28 1994-02-03 Matsushita Electric Works Ltd Quick-fit coupling esp. for waste pipes - has insert head with flange and groove engaging in bore of socket to be locked by arms of spring clip engaging in groove.
EP0665402A1 (en) * 1994-01-29 1995-08-02 ARMATURENFABRIK Hermann Voss GmbH + Co. Plug connector for pressure pipe systems
WO2003058064A1 (en) * 2002-01-11 2003-07-17 Robert Bosch Gmbh Fuel pump for an internal combustion engine
DE10236853A1 (en) * 2002-08-10 2004-02-26 Continental Teves Ag & Co. Ohg Radial piston pump for a slippage-controlled brake installation in motor vehicles has a retaining body with working pistons protruding into a crank chamber and a drive shaft to drive the pistons
US20050100466A1 (en) * 2003-01-09 2005-05-12 Nobuo Aoki Fuel supply pump
WO2006037676A1 (en) * 2004-10-06 2006-04-13 Siemens Aktiengesellschaft Radial piston pump comprising a roller tappet

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DE8708761U1 (en) * 1987-06-24 1988-10-20 Robert Bosch Gmbh, 7000 Stuttgart Fuel injection piston pump
DE4310192A1 (en) * 1992-07-28 1994-02-03 Matsushita Electric Works Ltd Quick-fit coupling esp. for waste pipes - has insert head with flange and groove engaging in bore of socket to be locked by arms of spring clip engaging in groove.
EP0665402A1 (en) * 1994-01-29 1995-08-02 ARMATURENFABRIK Hermann Voss GmbH + Co. Plug connector for pressure pipe systems
WO2003058064A1 (en) * 2002-01-11 2003-07-17 Robert Bosch Gmbh Fuel pump for an internal combustion engine
DE10236853A1 (en) * 2002-08-10 2004-02-26 Continental Teves Ag & Co. Ohg Radial piston pump for a slippage-controlled brake installation in motor vehicles has a retaining body with working pistons protruding into a crank chamber and a drive shaft to drive the pistons
US20050100466A1 (en) * 2003-01-09 2005-05-12 Nobuo Aoki Fuel supply pump
WO2006037676A1 (en) * 2004-10-06 2006-04-13 Siemens Aktiengesellschaft Radial piston pump comprising a roller tappet

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ITMI20131903A1 (en) * 2013-11-15 2015-05-16 Bosch Gmbh Robert HIGH PRESSURE PUMP FOR FUEL SUPPLY TO AN INTERNAL COMBUSTION ENGINE
WO2015071149A1 (en) * 2013-11-15 2015-05-21 Robert Bosch Gmbh High-pressure pump for feeding fuel to an internal-combusion engine
US11466649B2 (en) * 2017-12-13 2022-10-11 Robert Bosch Gmbh Pumping unit for feeding fuel, preferably diesel fuel, to an internal combustion engine

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KR20130103718A (en) 2013-09-24
EP2612017A1 (en) 2013-07-10
IT1401914B1 (en) 2013-08-28
JP2013540930A (en) 2013-11-07
CN103080530B (en) 2016-01-13
JP5654682B2 (en) 2015-01-14
RU2573434C2 (en) 2016-01-20
RU2013114165A (en) 2014-10-10
ITMI20101594A1 (en) 2012-03-02
CN103080530A (en) 2013-05-01
EP2612017B1 (en) 2014-12-10

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