High-pressure pump

Patent metadata

Field	Value
Publication number	US-10060420-B2
Application number	US-201414898986-A
Country	US
Kind code	B2
Filing date	Apr 29, 2014
Priority date	Jun 21, 2013
Publication date	Aug 28, 2018
Grant date	Aug 28, 2018

Abstract

A high-pressure pump including a drive shaft (2) supported about an axis of rotation (26) and having at least one cam (3). The pump includes at least two pistons (5); at least two cylinders (6) supporting the pistons (5); wherein the pistons (5) have longitudinal axes (16) oriented at an angle to each other in a projection of the piston longitudinal axes (16) in the direction of the axis of rotation (26) onto a fictitious projection plane perpendicular to the axis of rotation (26). Each of the pistons (5) is supported on a shaft rolling surface (4) of the drive shaft (2) having the at least one cam (3) indirectly by means of a respective supporting element (14) having a supporting rolling surface (15), such that a translational motion can be performed by the pistons (5) as the result of a rotational motion of the drive shaft (2), wherein the piston longitudinal axes (16) have an axial distance in the direction of the axis of rotation (26).

First claim

The invention claimed is:

1. A high-pressure pump ( 1 ), comprising
a drive shaft ( 2 ) mounted rotatably about a rotation axis ( 26 ) and having at least one cam ( 3 ),
at least two pistons ( 5 ),
at least two cylinders ( 6 ) for mounting of the at least two pistons ( 5 ), the pistons ( 5 ) each having a piston longitudinal axis ( 16 ), wherein on a projection of the piston longitudinal axes ( 16 ) in a direction of the rotation axis ( 26 ) of the drive shaft ( 2 ) onto a theoretical projection plane perpendicular to the rotation axis ( 26 ), the piston longitudinal axes ( 16 ) are oriented at an angle to each other,
wherein the at least two pistons ( 5 ) rest indirectly, each by means of a support element ( 14 ) having a support rolling face ( 15 ), on a shaft rolling face ( 4 ) of the drive shaft ( 2 ) having the at least one cam ( 3 ), so that the at least two pistons ( 5 ) can perform a translational movement as a result of rotational movement of the drive shaft ( 2 ),
characterized in that
the piston longitudinal axes ( 16 ) have an axial spacing ( 17 ) in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ),
contact rolling faces ( 18 ), of the support rolling faces ( 15 ) of the support elements ( 14 ) on the shaft rolling face ( 4 ) of the drive shaft ( 2 ) are separate from each other along the rotation axis ( 26 ) so as not to overlap each other, and
all support elements ( 14 ) with the support rolling faces ( 15 ) rest on just one common shaft rolling face ( 4 ) of the drive shaft ( 2 ) having the at least one cam ( 3 ).

2. The high-pressure pump as claimed in claim 1 , characterized in that the axial spacing ( 17 ) of the piston longitudinal axes ( 16 ) of the pistons ( 5 ) in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ) amounts to at least 30% of an axial extension ( 40 ) of the support rolling faces ( 15 ) in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ).

3. The high-pressure pump as claimed in claim 1 , characterized in that on a projection of the piston longitudinal axes ( 16 ) in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ) onto the theoretical projection plane, the piston longitudinal axes ( 16 ) are oriented at a minimum angle to each other of between 0° and 180°.

4. The high-pressure pump as claimed in claim 1 , characterized in that all pistons ( 5 ) rest indirectly, each by means of the support element ( 14 ) with the support rolling face ( 15 ), on the shaft rolling face ( 4 ) of just one drive shaft ( 2 ) having the at least one cam ( 3 ).

5. The high-pressure pump as claimed in claim 1 , characterized in that each one of a plurality of theoretical straight lines oriented parallel to the rotation axis ( 26 ) and lying continuously without interruption on the common shaft rolling face ( 4 ) has a constant distance from the rotation axis ( 26 ) of the drive shaft ( 2 ) in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ).

6. The high-pressure pump as claimed in claim 1 , characterized in that, on the projection of the piston longitudinal axes ( 16 ) in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ) onto the theoretical projection plane, all piston longitudinal axes ( 16 ) are arranged within an angular range of 120°.

7. A high-pressure injection system ( 36 ) for an internal combustion engine ( 39 ), comprising
a high-pressure pump ( 1 ),
a high-pressure rail ( 30 ), and
a pre-delivery pump ( 35 ) for delivering a fuel from a fuel tank ( 32 ) to the high-pressure pump ( 1 ),
characterized in that the high-pressure pump ( 1 ) is configured as a high-pressure pump ( 1 ) as claimed in claim 1 .

8. The high-pressure pump as claimed in claim 1 , characterized in that the axial spacing ( 17 ) of the piston longitudinal axes ( 16 ) of the pistons ( 5 ) in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ) amounts to at least 50% of an axial extension ( 40 ) of the support rolling faces ( 15 ) in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ).

9. The high-pressure pump as claimed in claim 1 , characterized in that the axial spacing ( 17 ) of the piston longitudinal axes ( 16 ) of the pistons ( 5 ) in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ) amounts to at least 70% of an axial extension ( 40 ) of the support rolling faces ( 15 ) in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ).

10. The high-pressure pump as claimed in claim 1 , characterized in that the axial spacing ( 17 ) of the piston longitudinal axes ( 16 ) of the pistons ( 5 ) in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ) amounts to at least 100% of an axial extension ( 40 ) of the support rolling faces ( 15 ) in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ).

11. The high-pressure pump as claimed in claim 1 , characterized in that in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ), the support rolling faces ( 15 ) of the support elements ( 14 ) have an axial spacing ( 41 ) of at least 1% of an axial extension ( 40 ) of the support rolling faces ( 15 ) in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ).

12. The high-pressure pump as claimed in claim 1 , characterized in that in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ), the support rolling faces ( 15 ) of the support elements ( 14 ) have an axial spacing ( 41 ) of at least 3% of an axial extension ( 40 ) of the support rolling faces ( 15 ) in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ).

13. The high-pressure pump as claimed in claim 1 , characterized in that in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ), the support rolling faces ( 15 ) of the support elements ( 14 ) have an axial spacing ( 41 ) of at least 5% of an axial extension ( 40 ) of the support rolling faces ( 15 ) in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ).

14. The high-pressure pump as claimed in claim 1 , characterized in that in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ), the support rolling faces ( 15 ) of the support elements ( 14 ) have an axial spacing ( 41 ) of at least 10% of an axial extension ( 40 ) of the support rolling faces ( 15 ) in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ).

15. The high-pressure pump as claimed in claim 1 , characterized in that all contact rolling faces ( 18 ) of the support rolling faces ( 15 ) of the support elements ( 14 ) on the shaft rolling face ( 4 ) of the drive shaft ( 2 ) have axial spacing therebetween.

16. The high-pressure pump as claimed in claim 1 , characterized in that on the projection of the piston longitudinal axes ( 16 ) in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ) onto the theoretical projection plane, the piston longitudinal axes ( 16 ) are oriented at a minimum angle to each other of between 2° and 178°.

17. The high-pressure pump as claimed in claim 1 , characterized in that on the projection of the piston longitudinal axes ( 16 ) in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ) onto the theoretical projection plane, the piston longitudinal axes ( 16 ) are oriented at a minimum angle to each other of between 10° and 120°.

18. The high-pressure pump as claimed in claim 1 , characterized in that on the projection of the piston longitudinal axes ( 16 ) in the direction of the rotation axis ( 26 ) of the drive shaft ( 2 ) onto the theoretical projection plane

Assignees

• Bosch Gmbh Robert

Inventors

• Dohms Ralf

Classifications

• F04B9/042 Primary

  the means being cams · CPC title

• F02M63/0265 Primary

  Pumps feeding common rails · CPC title

• F02M59/102

  Mechanical drive, e.g. tappets or cams (F02M45/063 takes precedence) · CPC title

• F02M2200/02

  Fuel-injection apparatus having means for reducing wear · CPC title

• F04B1/0417

  consisting of two or more cylindrical elements, e.g. rollers · CPC title