METHOD FOR MOUNTING AT LEAST ONE SEALING RING ON A CAMSHAFT IN A BEARING LINE OF AN INTERNAL COMBUSTION ENGINE, AND CAMSHAFT HAVING AT LEAST ONE SEALING RING MOUNTED IN SUCH A WAY

Abstract

A method for mounting a camshaft in a bearing line of a cylinder head cover of an internal combustion engine may involve mounting a sealing ring in a groove extending radially circumferentially on an outer diameter of the camshaft. The sealing ring may be at least partly formed of an elastically deformable polymer such as polytetrafluoroethylene (PTFE). The method may further involve sliding a calibrating tool having a rotationally symmetrical opening onto the camshaft or sliding the camshaft into the calibrating tool. A smallest inside diameter of the rotationally symmetrical opening may be greater than an outside diameter of the camshaft in a region of the groove but less than an outside diameter of the sealing ring. Consequently, the sealing ring is pressed into the groove and is frictionally and interlockingly held in the groove.

Claims

1.-14. (canceled)

15. A method for mounting a camshaft in a bearing line of a cylinder head cover of an internal combustion engine, the method comprising: mounting a sealing ring on the camshaft by positioning the sealing ring in a groove that radially encircles an outer diameter in a region of the camshaft, the sealing ring comprising an elastically deformable polymer; and positioning a calibrating tool relative to the sealing ring, wherein the calibrating tool has a rotationally symmetrical opening, wherein a smallest inside diameter of the rotationally symmetrical opening is greater than the outer diameter of the camshaft in the region of the camshaft but is less than an outside diameter of the sealing ring, wherein the calibrating tool is pushed over the sealing ring or the camshaft is pushed into the calibrating tool such that the sealing ring is pressed into and held in the groove in a force-fitting and form-fitting manner.

16. The method of claim 15 wherein the sealing ring comprises polytetrafluoroethylene (PTFE).

17. The method of claim 15 comprising introducing the camshaft into bearings of the bearing line, wherein the bearings are mounted on a cylinder head of the internal combustion engine.

18. The method of claim 17 comprising pulling or stripping the calibrating tool off the camshaft before or during the introduction of the camshaft into the bearing line.

19. The method of claim 17 comprising cooling the camshaft before introducing the camshaft into the bearings of the bearing line.

20. The method of claim 17 wherein upon introducing the camshaft into the bearings, the camshaft with the mounted sealing ring is pushed by the calibrating tool disposed in front of a first of the bearings in an introduction direction of the camshaft, thereby pressing the sealing ring deeper into the groove such that the sealing ring is held in the groove in the force-fitting and form-fitting manner.

21. The method of claim 15 wherein the calibrating tool includes a conically tapering region that starts at a first side of an opening of the calibrating tool, wherein the first side of the opening of the calibrating tool is pushed onto the sealing ring first, wherein an inside diameter of the opening at the first side is greater than the outside diameter of the sealing ring after the sealing ring has been positioned in the groove.

22. The method of claim 15 comprising cooling the camshaft before positioning the calibrating tool relative to the sealing ring.

23. The method of claim 15 comprising cooling the camshaft before mounting the sealing ring.

24. The method of claim 15 wherein after the sealing ring is mounted on the camshaft, the method comprises cooling the camshaft and the sealing ring together.

25. The method of claim 15 comprising: pushing the calibrating tool over the sealing ring, which presses the sealing ring deeper into the groove; and then cooling the camshaft.

26. The method of claim 15 comprising: cooling the camshaft; and then pushing the calibrating tool over the sealing ring, which presses the sealing ring deeper into the groove.

27. The method of claim 15 wherein the calibrating tool presses the sealing ring into the groove to an extent such that an outer circumferential surface of the sealing ring, in a region of its smallest inside diameter, does not reach a base of the groove.

28. The method of claim 15 comprising cooling the camshaft with the mounted sealing ring and the calibrating tool.

29. The method of claim 15 comprising cooling the camshaft with the mounted sealing ring but without the calibrating tool.

30. The method of claim 15 wherein the sealing ring is a first sealing ring and the groove is a first groove, the method comprising positioning a second sealing ring in a second groove on the camshaft in a force-fitting and form-fitting manner such that the second sealing ring is spaced apart from the first sealing ring along a longitudinal axis of the camshaft.

31. The camshaft referenced in claim 15 wherein the sealing ring is disposed in the groove in the form-fitting and force-fitting manner, where the sealing ring is disposed in the groove according to the method recited in claim 15.

32. A method for mounting a camshaft in a bearing line of a cylinder head cover of an internal combustion engine, the method comprising: mounting a polytetrafluoroethylene (PTFE) sealing ring on a groove of the camshaft; and positioning a calibrating tool relative to the sealing ring, wherein a smallest inside diameter of an opening of the calibrating tool is greater than an outer diameter of the camshaft in a region adjacent to the groove but is less than an outside diameter of the sealing ring, wherein the calibrating tool is pushed over the sealing ring or the camshaft is pushed into the calibrating tool such that the opening of the calibrating tool presses the sealing ring into the groove in a force-fitting and form-fitting manner.

33. The method of claim 32 wherein positioning the calibrating tool relative to the sealing ring comprises passing the sealing ring through a conically tapering region of the opening of the calibrating tool.

Description

[0023] The invention will be explained in more detail below by way of example. The features described and identified in the individual examples and figures can be combined with one another irrespective of the particular example or the figure. Individual features are not restricted to the respective example or the respective figure.

[0024] In the figures:

[0025] FIG. 1 shows a view of part of a camshaft on an end side without sealing rings;

[0026] FIG. 2 shows the illustration from FIG. 1 with preassembled expanded sealing rings;

[0027] FIG. 3 shows that part of the camshaft which is shown in FIGS. 1 and 2 with a calibrating tool pushed onto the sealing ring;

[0028] FIG. 4 an illustration of a camshaft with an end piece which is provided with sealing rings and at which a calibrating tool is present during the mounting of the camshaft in a bearing line of a cylinder head;

[0029] FIG. 5 shows, in schematic form, a calibrating tool which is arranged on a bearing of a bearing line and with which pressing in of expanded sealing rings can be achieved;

[0030] FIG. 6 shows, in schematic form, an illustration of possible sequences for conducting the method during the mounting of at least one sealing ring on a camshaft.

[0031] FIG. 1 shows part of a camshaft 2, on the one end side of which an end piece 2.1 is part of the camshaft 2 or the end piece 2.1 is connected to the camshaft 2. In the region of the end piece 2.1, two parallel grooves 3 are formed in a radially encircling manner perpendicular to the longitudinal axis of the camshaft 2.

[0032] In the illustration of FIG. 2, two sealing rings 1 made of PTFE have been pushed onto the end piece 2.1 from the side shown on the left here to such an extent that the sealing rings 1 are also held in the respective groove 3 in a form-fitting manner, but protrude to too high an extent over the outer surface in the region of the end piece 2.1. The elastic sealing rings 1 have expanded upon being pushed on.

[0033] By the calibrating tool 4 being pushed from one side onto the region of the end piece 2.1 of the camshaft 2, the sealing rings 1 are pressed deeper into the respective groove 3. In the example shown in FIG. 3, the calibrating tool 4 comprises a hollow cylinder. In the example shown in FIG. 3, the inner side of the calibrating tool 4 comprises, on the end side which is pushed first onto the end piece 2.1 and the sealing rings 1, a conically tapering region 4.1, the largest inside diameter of which is arranged on the end side which is pushed first onto the end piece 2.1. The conically tapering region 4.1 is adjoined by a region at which its inside diameter is constant and with the smallest inside diameter which in turn corresponds to the largest outside diameter of the sealing rings 1 and which the sealing rings 1 are intended to have during the mounting of the camshaft 2 in the bearing line. The region of the calibrating tool 4 with the constant inside diameter has a width in the direction of the longitudinal axis of the camshaft 2, with which it can be ensured that all of the sealing rings 1 are pressed into the respective groove 3 to a corresponding depth when the calibrating tool 4 has been pushed onto the end piece 2.1 and the sealing rings 1.

[0034] By the calibrating tool 4 being pushed on, the sealing rings are pressed deeper into the grooves 3 to such an extent that they protrude with their outer diameter over the outer surface of the end piece 2.1 and do not touch the base of the respective groove 3.

[0035] The arrow in FIG. 3 is intended to clarify the direction of movement of the calibrating tool 4 as the latter is being pushed onto the respective sealing ring 1, by means of which direction of movement the respective sealing ring 1 can be introduced in a defined manner in to the corresponding groove 3 and fixed therein in a form-fitting and force-fitting manner.

[0036] FIG. 4 shows in schematic form a view of a camshaft 2 which has been pushed into the bearing line, formed by the bearings 5.1, 5.2 and 5.3, of an internal combustion engine, here from the left to the right. The two sealing rings 1 which are fixed in the grooves 3 of the end piece 2.1 have been pressed by means of the calibrating tool 4 deeper into the respective groove 3 after being pushed on and correspondingly expanding.

[0037] After the mounting of the camshaft 2, the calibrating tool 4 can be pulled off again. The pulling off during the mounting of the camshaft 2 can be assisted by one of the bearings 5.x, against which the calibrating tool 4 abuts upon introduction of the camshaft 2 into the bearing line, and is thereby stripped off. This state of affairs is not illustrated in FIG. 4.

[0038] FIG. 5 shows an example in which a calibrating tool 4 is supported on one of the bearings 5.x during the mounting of a camshaft 2 in the closed bearing line.

[0039] However, a calibrating tool 4 can also be correspondingly moved by a manipulator unit (not shown) such that pushing on and pulling off are possible.

[0040] FIG. 6 shows various possibilities for the mounting of at least one sealing ring on a camshaft. A camshaft with or without a sealing ring already mounted can be cooled prior to the introduction into the bearing line of an internal combustion engine, as is mentioned in the general part of the description.

[0041] The cooling of the camshaft can also take place with the at least one sealing ring already mounted, together with the calibrating tool or after the calibrating tool is pulled off before the camshaft is mounted in the bearing line of the internal combustion engine.