ROLLER TAPPET FOR A FUEL PUMP

Abstract

A roller tappet for a fuel pump is provided that has a guide housing which includes a drive-side and output-side section of the same external diameter, and a separate support body extending longitudinally through the guide housing. An upper face on the drive-side section carries a pin with a roller thereon. A lower face of the output-side section interacts at least indirectly with an arrangement for a pump piston. The guide housing includes a drive-side section and an output side section that are separate, axially spaced rings connected to one another via the support body. The support body has a first ring area with the upper face and a second ring area with the lower face. The first ring area is connected to an inner jacket of the drive-side section and the second ring area is connected to an inner jacket of the output-side section.

Claims

1. A roller tappet for an internal combustion engine, the roller tappet comprising: a guide housing having: a drive-side section, and an output-side section axially spaced and separated from the drive-side section, each of the drive-side section and the output-side section configured with a same outer diameter, a separate support body having: a first end having a first ring area fixedly connected to the drive-side section, the first ring area having a pin configured to receive a roller, a second end having a second ring area fixedly connected to the output-side section, the second ring area arranged to receive a pump piston, and longitudinal struts arranged to fixedly connect the first ring area to the second ring area.

2. The roller tappet of claim 1, wherein the support body with the longitudinal struts and the first and second ring areas is in one piece and is produced from thin-walled sheet steel by punching and bending.

3. The roller tappet of claim 1, wherein the first and second ring areas of the support body are connected via two longitudinal struts, and at least the first ring area of the support body is formed with opposed flat, indented extensions, each of the flat, indented extensions: i) adjoined with one of the two longitudinal struts, and ii) having a bore configured to receive the pin.

4. The roller tappet of claim 1, wherein a first inner jacket of the drive-side section is fixedly connected to the first ring area and a second inner jacket of the output-side section is fixedly connected to the second ring area.

5. The roller tappet of claim 1, wherein an exposed length of the longitudinal struts of the support body exceeds a sum of a first length of the longitudinal struts covered by the drive-side section and a second length of the longitudinal struts covered by the output-side section

6. The roller tappet of claim 1, wherein the output-side section of the guide housing is formed with a cross strut, and a lower face of the second ring area abuts with the cross strut.

7. The roller tappet of claim 1, wherein at least one of the drive-side section or the output-side section of the guide housing is produced from sheet steel.

8. The roller tappet of claim 1, wherein the drive-side section and the output-side section are welded, riveted, clipped or press-fitted to the corresponding first and second ring areas of the support body.

9. The roller tappet of claim 1, wherein: the first ring area further comprises a first bore and a second bore, each of the first and second bores configured to receive the pin, and the drive-side section further comprises a third bore aligned with the first bore, and a fourth bore aligned with the second bore.

10. The roller tappet of claim 1, wherein the output-side section further comprises an anti-rotation body protruding from an outer jacket of the output-side section.

11. The roller tappet of claim 3, wherein the at least the first ring area further comprises two opposed end faces configured to form a portion of the at least the first ring area arranged outside of the opposed flat, indented extensions.

12. The roller tappet of claim 11, wherein a first end face of the two opposed end faces is offset from a second end face of the two opposed end faces.

13. The roller tappet of claim 11, wherein a first end face of the two opposed end faces engages a second end face of the two opposed end faces.

14. A tappet for an internal combustion engine, the tappet comprising: a drive-side housing, an output-side housing axially spaced and separated from the drive-side housing, the output-side housing and the drive-side housing having a same outer diameter, and a support body having: a first ring area at a first end, the first ring area fixedly connected to the drive-side housing, and a second ring area at a second end, the second ring area fixedly connected to the output-side housing, and at least one longitudinal strut fixedly connecting the first ring area to the second ring area, and the first ring area, the second ring area, and the at least one longitudinal strut are integrally formed from one piece.

15. The tappet of claim 14, wherein the first ring area, the second ring area, and the at least one longitudinal strut are integrally formed via bending of sheet steel.

16. The tappet of claim 15, wherein the drive-side housing and the output-side housing are formed as steel rings via a drawing process.

17. The tappet of claim 16, wherein a first inner jacket of the drive-side housing is fixedly connected to the first ring area and a second inner jacket of the output-side housing is fixedly connected to the second ring area.

18. The tappet of claim 17, wherein the output-side housing is formed with a transverse strut configured to abut with an end of the support body.

19. The tappet of claim 17, wherein at least one of the first ring area or the second ring area is formed with two opposed flat, indented extensions configured with bores to receive a pin configured for a roller.

20. A tappet for an internal combustion engine, the tappet comprising: a drive-side housing ring, an output-side housing ring having a same outer diameter as the drive-side housing ring, and a support body having: a first ring area fixedly connected to the drive-side housing ring, the first ring area having two flat, indented extensions configured to receive a pin configured for a roller, a second ring area fixedly connected to the output-side housing ring and axially offset from the first ring area, and at least one longitudinal strut configured to fixedly connect the first ring area to the second ring area, and the drive-side housing ring is axially offset from the output-side housing ring such that a portion of the at least one longitudinal strut is not surrounded by either of the drive-side housing ring or the output-side housing ring, defining an exposed portion arranged between the drive-side housing ring and the output-side housing ring in a longitudinal direction of the at least one longitudinal strut.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The disclosure is explained with reference to the drawings.

[0025] FIG. 1 shows a three-dimensional view of the roller tappet, partially broken up; and

[0026] FIG. 2 shows the roller tappet in an exploded view.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] The figures show a roller tappet 1 for a fuel pump of an internal combustion engine. The roller tappet 1 is suitable for large installation spaces.

[0028] The roller tappet 1 has a guide housing 2. This consists of a drive-side and an output-side section 3, 4 of the same external diameter. Both sections 3, 4 are separate and axially spaced rings made of sheet steel. A thin-walled and separate support body 5, likewise made of sheet steel, extends longitudinally through the two-part guide housing 2. The support body 5 carries a roller 9 on its upper face 7 on the drive-side section 3. The latter sits on a pin 21 which is inserted at the end into bores 20 of the support body 5.

[0029] It can be seen that the support body 5 has a first ring area 12 with the upper face 7 and a second, axially spaced apart ring area 13 with the lower face 10. The ring areas 12, 13 are welded to the respective inner jackets 14, 15 of the sections 3, 4 and lie within their height. A one-piece connection of the ring areas 12, 13 is established via longitudinal struts 16 which extend from opposing inner faces 17, 18 of the ring areas 12, 13. As can best be seen in FIG. 1, the longitudinal struts 16 of the support body 5 are exposed over most of their length with respect to the sections 3, 4 of the guide housing 2.

[0030] The aforementioned bores 20 for the pin 21 in the first ring area 12 lie in the circumferential section of the longitudinal struts 16, which are designed as planar, indented extensions 19. In alignment with these, the upper, drive-side section 3 has two bores 28. As shown in FIG. 1, the pin 21 does not protrude into these bores 28. The pin 21 can, however, sit in the bores 28, which would additionally fix the upper section 3.

[0031] From FIG. 2 it can be seen that the support body 5, after punching of its contour, is simply bent around an imaginary center in the blank, which coincides with the axial line of its ring areas 12, 13 and at the same time of the roller tappet 1. End faces 22, 23 of the ring areas 12, 13 run towards one another in the final stage of the bending process, where the end faces 22 of the first, upper ring area 12 adjoin one another.

[0032] As can also be seen from FIG. 2, the output-side section 4 of the guide housing 2 is provided in one piece with a transverse strut 25 at its output-side end 24. The areas lying on both sides of the cross brace 25 are punched out. An arrangement 11 for a pump piston is formed on an underside 26 of the cross strut 25. As shown, the second ring area 13 of the support body 5 rests with its lower end 10 on an inner surface 8 of the cross strut 25.

[0033] A separate anti-rotation body 6 also protrudes from an outer jacket 27 of the lower, output-side section 4 of the guide housing 2. It has a mushroom-shaped cross-section.

LIST OF REFERENCE CHARACTERS

[0034] 1 Roller

[0035] 2 Guide housing

[0036] 3 Drive-side section

[0037] 4 Output-side section

[0038] 5 Support body

[0039] 6 Anti-rotation body

[0040] 7 Upper face

[0041] 8 Inner face

[0042] 9 Roller

[0043] 10 Lower face

[0044] 11 Arrangement

[0045] 12 First ring area

[0046] 13 Second ring area

[0047] 14 Inner jacket

[0048] 15 Inner jacket

[0049] 16 Longitudinal strut

[0050] 17 Inner face

[0051] 18 Inner face

[0052] 19 Extension

[0053] 20 Bore

[0054] 21 Pin

[0055] 22 End face

[0056] 23 End face

[0057] 24 End

[0058] 25 Cross brace

[0059] 26 Underside

[0060] 27 Outer jacket

[0061] 28 Bore