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

{
  "publication_number": "US10815836B2",
  "country": "US",
  "kind": "B2",
  "title": "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. 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.",
    "2. The method of claim 1 wherein the sealing ring comprises polytetrafluoroethylene (PTFE).",
    "3. The method of claim 1 comprising introducing the camshaft into bearings of the bearing line, wherein the bearings are mounted on a cylinder head of the internal combustion engine.",
    "4. The method of claim 3 comprising pulling or stripping the calibrating tool off the camshaft before or during the introduction of the camshaft into the bearing line.",
    "5. The method of claim 3 comprising cooling the camshaft before introducing the camshaft into the bearings of the bearing line.",
    "6. The method of claim 3 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.",
    "7. The method of claim 1 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.",
    "8. The method of claim 1 comprising cooling the camshaft before positioning the calibrating tool relative to the sealing ring.",
    "9. The method of claim 1 comprising cooling the camshaft before mounting the sealing ring.",
    "10. The method of claim 1 wherein after the sealing ring is mounted on the camshaft, the method comprises cooling the camshaft and the sealing ring together.",
    "11. The method of claim 1 comprising: pushing the calibrating tool over the sealing ring, which presses the sealing ring deeper into the groove; and then cooling the camshaft.",
    "12. The method of claim 1 comprising: cooling the camshaft; and then pushing the calibrating tool over the sealing ring, which presses the sealing ring deeper into the groove.",
    "13. The method of claim 1 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.",
    "14. The method of claim 1 comprising cooling the camshaft with the mounted sealing ring and the calibrating tool.",
    "15. The method of claim 1 comprising cooling the camshaft with the mounted sealing ring but without the calibrating tool.",
    "16. The method of claim 1 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.",
    "17. The camshaft referenced in claim 1 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 1.",
    "18. 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.",
    "19. The method of claim 18 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_excerpt": "The present disclosure generally relates to camshafts, including methods for mounting sealing rings on camshafts in bearing lines of internal combustion engines.\n\nCamshafts are mounted rotatably on a cylinder head of an internal combustion engine under a sealed cylinder head cover in bearings which form a bearing line. A suitable lubricating oil is used for lubrication, and therefore, in addition to the sealing of the cylinder head cover on the cylinder head, sealing elements are also required on a camshaft. For this purpose, sealing rings are fixed on a suitable surface of the camshaft, in particular in the region of an end piece, in each case by an encircling groove formed radially on the surface.\n\nFor cost reasons, camshafts are inserted as a whole part into the bearings which form a bearing line. The bearings are generally already closed here, and therefore the camshaft has to be introduced through the openings of the individual bearings.\n\nHowever, problems arise here with those regions of the sealing rings which protrude over the outer circumference of the camshaft and which may be damaged during the mounting of the camshaft. The excess length is increased by the mounting of the sealing rings on the camshaft since sealing rings expand. The expansion is also not sufficiently reduced by the elasticity on its own. A sealing ring is thereby held in a force- and form-fitting manner in a groove formed on the outer circumferential surface. However, the fixing which can thus be achieved does not sufficiently meet the requirements for a secure sealing action and fastening of the respective sealing ring to the camshaft.",
  "cpc": [
    "F01L 1/047",
    "B25B 27/0028",
    "F01L 2001/0476",
    "F01L 2800/09",
    "F01L 2810/02",
    "F16J 15/3268"
  ],
  "ipc": [
    "B25B 27/00",
    "F01L 1/02",
    "F01L 1/047",
    "F16J 15/3268"
  ],
  "assignees": [
    "ThyssenKrupp AG",
    "ThyssenKrupp Presta TecCenter AG"
  ],
  "inventors": [
    "Marko Curlic",
    "Aaron Pfitscher",
    "Manfred Muster",
    "Kanwar Bir Singh SIDHU",
    "Reinhard Schlemmer"
  ],
  "filing_date": "2017-11-28",
  "publication_date": "2020-10-27",
  "grant_date": "2020-10-27",
  "priority_date": "2016-12-02",
  "application_number": "US-201716465640-A",
  "family_id": "60915467",
  "cited_by_count": 1,
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}