EP1904756A1

EP1904756A1 - Clutch release bearing in contact with a disk spring

Info

Publication number: EP1904756A1
Application number: EP06762069A
Authority: EP
Inventors: Ludwig Winkelmann; Steffen Dittmer
Original assignee: Schaeffler KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2005-07-13
Filing date: 2006-06-17
Publication date: 2008-04-02
Also published as: KR20080025401A; WO2007006394A1; JP5140845B2; BRPI0613472A2; BRPI0613472A8; DE102005032676A1; US20080210515A1; CN101218449B; RU2386060C2; JP2009501299A; DE102005032676B4; RU2008105394A; US8286775B2; CN101218449A

Abstract

The invention relates to a clutch release bearing (21) that is in contact with a disk spring. Said clutch release bearing (21) comprises at least one curved stop face (12, 28, 30, 33) that is located at a radial distance from the axis of rotation (4) of the clutch release bearing (21) and is used for stopping at least one end (39) of at least one spring tongue (40) of the disk spring.

Description

Name of the invention

Clutch release bearing in contact with a diaphragm spring

description

Field of the invention

The invention relates to a Kupplungsausrϋcklager in contact with a plate spring, wherein the clutch release bearing has at least one curved and radially to the axis of rotation of the clutch release bearing spaced starting surface for the start of at least one end of at least one spring tongue of the plate spring.

Background of the invention

A clutch release bearing of the generic type describes DE 37 438 53 A1. The contact surface is formed either on an inner ring or on an outer ring of the clutch release bearing. The ends of the spring tongues are in touching contact with the contact surface. In this case, the contact surface is either an annular surface extending around the axis of rotation. As an alternative, a plurality of contact surfaces which are segment-like and circumferentially adjacent to one another are formed on the clutch release bearing. If several of the segment-like contact surfaces are formed on the clutch release bearing, as described in DE 37 438 53 A1, for example, see ribs between the contact surfaces for engagement between the spring tongues provided.

When separating the clutch, the circumferential contact surface on the bearing ring of the release bearing is pressed with force on the spring tongue (s), the spring tongues thereby spring axially. The contact on which the spring tongues meet the contact surface, shifts during compression and rebound on the contact surface radially inwardly in the direction of the axis of rotation of the release bearing or radially away from the axis of rotation. The contact also shifts with increasing wear in the coupling.

The meeting on the contact surface ends of the spring tongues are therefore often bent so curved that they are convexly bulged to the contact surface at the camp and that they always run with compression and rebound with line contact to often curved also convex towards the end of the spring tongue contact surface , An example of such a release bearing assembly is described in DE 37 438 53 A1.

However, there are clutch or vehicle manufacturers who use disc springs for various reasons, the ends of the spring tongues are currently running. Such a release bearing arrangement is described in EP 015 383 59 A1. The ends are usually in contact with a curved contact surface. These release bearing arrangements generally have optimum line contact only at one operating point, which changes into two-point contact when displaced in a radial direction and becomes progressively smaller when displaced in the other radial direction and finally ends in a one-point contact. Upon actuation of the clutch, the contact will move radially outward into a single-point contact and when moving up due to wear in a two-point contact. Such minimizations of contact lead to high surface pressures and promote impermissible wear in contact at the contact and contact surfaces. The effects in contact with release bearing arrangements of the prior art are described with the figures 1 and 2.

Figure 1 shows schematically the contact and contact conditions during contact of a spring tongue to Ausrücklageranordnung, as described in EP 015 383 5A1. As a curved contact surface, a part of a lateral surface of a toroidal body 1 is considered by way of example. The toroidal Body 1 is shown in simplified form by grid lines 2 and 3. The axial bulge of the contact surface is symbolized by the grid lines 2. The grid lines 2 extend in planes in which the axis of rotation 4 extends and which are rectified with the axis of rotation 4. Circumferential curvatures of the contact surface in planes which are pierced perpendicularly by the axis of rotation 4 are symbolized by the grid lines 3. The contact surface of the non-curved end of a spring tongue is symbolized by the surface 5.

The generating line marked with 3.1 symbolizes the axial line 3.1 of the contact surface which projects axially the most. In FIG. 2, a longitudinal section through the body along the axis of rotation 4, the surface line 3.1 marks the reversal point (vertex) of a curvature described in the longitudinal section through one of the grid lines 2.

The contact of the surface 5 with the surface line 3.1 at the apex of the curvature results in an optimal line contact 6. The line described by the line contact 6 is shown in Figure 1 the course of the surface line 3.1 corresponding curved. If the surface 5 runs tilted in the direction of the arrow 7 on the contact surface, finally results in the contacts 8 and 9, a two-point contact. As surface 5 tilts in the direction of arrow 10 on the start-up surface, the line contact becomes progressively smaller as long as surface 5 and the abutment surface are finally in point 11 in single-point contact.

Summary of the invention

The object of the invention is therefore to provide a clutch release bearing, with which an optimal contact is made to the spring tongues, in particular to reduce the wear in the assembly.

This object is achieved with a clutch release bearing according to the features of claim 1 and by the features of further dependent claims designed.

The release bearing has a plurality of circumferentially successive following contact surfaces. The contact surfaces are either directly adjacent to one another and thereby overlap at chamfers or the contact surfaces are separated from one another, so that e.g. Functional elements of the release bearing between the contact surfaces are arranged.

Thus, an embodiment of the invention that between at least two circumferentially successive of the contact surfaces an axial rippenarti- ger extension is formed, wherein the axial extension is provided for engagement in a circumferential distance between two circumferentially adjacent to each other of the spring tongues. The extension is tapered roof-shaped in the axial direction.

The disc springs have any number of spring tongues, which are distributed to one another with uniform pitch to each other or on the circumference with different distances. The spring tongues of a diaphragm spring have either the same or different shape from each other. Each of the contact surfaces is / are preferably assigned to one of the ends alternatively also more ends of a spring tongue.

Each of the abutment surfaces is curved in the planes running along the axis of rotation, but not in the circumferential direction. The contact surface is described in vertically pierced by the axis of rotation planes of any number of mutually adjacent and parallel aligned rectilinear generatrices. Each of the generating lines runs tangentially and rectilinearly in each case to an imaginary circle located in one of the planes. The axis of rotation of the clutch release bearing pierces the circle at the center of the circle vertically.

The contact surface is convexly convex towards the end and described by generatrices, for example, by a radius, the course of the Curve of an ellipse correspond or any other convex curved.

An embodiment of the invention provides that the contact surface is described by at least one segment of an outer circumferential surface of a cylinder. The axis of symmetry of the cylinder is tangent to an imaginary circumferential line about the axis of rotation and is parallel to the surface lines. The parallel distance between the axis of symmetry and each of the surface lines of the contact surface is preferably at least 5 mm and thus corresponds to the radius of the cylinder.

The contact surfaces are fixed either to the inner ring or to the outer ring of Kuppiungsausrickiagers. The contact surfaces are either fixed directly to the material of the ring in question or at least one pressure piece or the like. As materials for the inner ring, outer ring or for the annular pressure piece is preferably a tempering steel such as C45; CF 53, C75 or a deep-drawing tool steel such as C80 U used.

The run-up piece is produced, for example, as a deep-drawing, embossing or extruded part and subjected to a heat treatment. The run-flat surfaces are alternatively provided with a wear-resistant, heat-resistant, low-roughness surface of hard coatings, e.g. made of plastic, hard materials or ceramic or nickel-aluminum alloys. The coatings are also provided, for example, by plasma coating, sintering, chemical coating or by spraying in the flame spraying, arc spraying, plasma or high-speed coating, with the trade name "Tritonur". Spraying or by vapor deposition or sputtering, vacuum or plasma-assisted method applied.

The pressure piece or any other suitable component, for example, optionally of plastic, hard metal, hardened sheet or other suitable materials or any combination of these. The pressure pieces are optionally snapped onto the corresponding bearing ring, glued on, welded on, sprayed on (applied by spraying, overmolding or the like) or fastened in another suitable manner to the bearing ring in a material, positive or non-positive manner. Fastening options are eg non-positive by interference fit, positive fit by snap connections and cohesively by soldering, ultrasonic bonding and hot stamping and gluing.

Alternative materials for the pressure pieces with contact surfaces or alternatively at least for the contact surfaces are thermosets or thermosets. Preferred thermoplastics are, for example, highly heat-resistant polyamides, polyaryl ether ketones (PEAK). Polyamide 46 (PA 46) or partially aromatic polyamides, preferably polyphthalamide (PPA) or polyhexamethylene terephthalamide (PA6T) or copolymer, polyhexamethylene isophthalamide (PA6T / 6I), are preferably used in the field of polyamides. and / or polyhexamethylene adipamide (PA6T / 66, PA6T / 6I / 66) or poly-methyl pentamethylene terephthalamide (PA6T / MPMDT) with friction and wear-resistant and strength-increasing additives. Suitable additives are carbon fibers and / or aramid fibers in a weight fraction of 1 to 40%, preferably carbon fibers with a weight fraction of 20 to 30%, aramid fibers with a weight fraction of 1 to 15% and solid lubricants such as molybdenum disulfide with a weight fraction of 1 to 5%. together with or alternatively graphite in a weight proportion of 1 to 10%, together with or alternatively polytetrafluoroethylene (PTFE) in a weight proportion of 1 to 30%, preferably a PTFE portion of 5 to 15% by weight, together with or alternatively polyphenylene sulfone (PPSo2, ceramer) in a weight proportion of 1 to 30%, preferably 1 to 15% by weight.

The contact surface is preferably introduced into the bearing rings and pressure plates made of sheet metal front side by forming.

Hard metals are, for example, tungsten carbides or titanium-containing, which are provided with binder and sintered accordingly. Brief description of the drawings

The invention will be explained in more detail with reference to embodiments. Show it.

Figure 1 principle and the different Berührverhältnisse in contact a spring tongue with a contact surface on release bearings of the

Prior art,

FIG. 2 shows a partial section, which is rectified with the axis of rotation, through the toroidal body according to FIG. 1,

FIG. 3 Description of the geometric conditions at the contact surfaces of an embodiment of the invention,

FIG. 4 shows a longitudinal section along the axis of rotation through an exemplary embodiment of a clutch release bearing,

FIG. 5 shows a partial view of an exemplary embodiment of a bearing ring, in which peripheral surfaces are introduced directly adjacent to one another of the contact surfaces,

FIG. 6 shows a front view of a pressure piece with a plurality of contact surfaces which are peripherally separated from one another by ribs,

7 shows a longitudinal section through the pressure piece according to FIG. 6 along the line VII-VII, FIG.

FIG. 8 shows the detail Z from FIG. 7, enlarged and not to scale, with the description of the geometry of one of the contact surfaces;

FIG. 9 shows a sectional partial view of a bearing ring with an attached pressure piece, 10 shows a further partial view of a bearing ring with an attached pressure piece in section,

11 is a sectional partial view of a bearing ring with an attached pressure piece,

FIG. 12 shows a partial section along a further exemplary embodiment of an inner ring on which contact surfaces are formed directly,

13 shows a partial section through an inner ring produced by cold forming with embossed contact surfaces.

Detailed description of the drawing

The illustrations in FIGS. 1 and 2 are described in the chapter "Background of the invention".

FIG. 3 shows a roughly schematic example of the geometric relationships of a contact surface 12. The contact surface 12 is a partial surface of a cylinder 13. The axis of symmetry 18 of the cylinder 13 intersects tangentially at the point of intersection 18a the circumferential line 19 of a circle 14 or a circle plane 14. The rotational axis 15 of a release bearing (not further illustrated) penetrates the circular plane 14 in the center 16 of the circle 14. The contact surface 12 is described by any number of generatrices 17 and curved in planes that are rectified with the rotational axis 15. The generatrices 17 of the contact surface 12 are aligned parallel to each other and to the axis of symmetry 18 of the cylinder 13, and thus also in the image plane. Since the contact surface 12 is part surface of a cylinder 13, R is the radius of the cylinder and therefore the distance for all generatrices 17 to the symmetry axis 18 is equal. The distance between the respective generatrix and an imaginary axis which is in the same position relative to the axis of symmetry becomes, as an alternative to the embodiment described above, ever greater, the farther the respective generatrix is away from the apex line 20. Alternatively, this distance becomes smaller and smaller on cam-shaped contact surfaces the farther the respective surface line is from the top line.

FIG. 4 shows a clutch release bearing 21 comprising an outer ring 22, an inner ring 23, balls 24 in a cage 25 and a guide and centering sleeve of the release bearing housing 26. The inner ring 23 has contact surfaces 28 on a rim 27 folded radially inward by cold forming , The contact surfaces 28 are embossed in the board 27. Corresponding contact surfaces may also be formed on the guide and centering sleeve as an alternative to the variant just mentioned.

Figure 5 shows a bearing ring 29, either an inner ring or an outer ring, are stamped on the thrust surfaces 30 of the release bearing according to the invention, which are immediately adjacent to each other and merge into bevels 31 into each other.

FIG. 6 and FIG. 7 show an annular pressure piece 32 with stop faces 33 spaced from one another on the circumferential side. The generatrices of the stop faces 33 are aligned tangentially. Between the contact surfaces 33 axial projections 34 are formed, which are tapered roof-shaped at the ends.

FIG. 8 shows the curvature 35 of the contact surface 33 in a plane aligned parallel to the axis of rotation 4, in this case the plane of the drawing of FIG. 8. The curvature 35 is described by a radius R. The generatrices in a plane perpendicular to the plane of the drawing are rectilinearly aligned without curvature. The pressure piece 32 is attached to the front side to an inner or outer ring by gluing or welding. Figure 9 shows an embodiment of an inner ring 36 with a pressure piece 37. The pressure piece has a plurality of contact surfaces 33 and is pressed firmly on the inner ring 36 and / or glued.

Figure 10 shows the contact of one end 39 of a spring tongue 40 only partially shown to a contact surface 33. The spring tongues 40 and their ends 39 are in the end positions radially inward or radially outward in the line contacts 41 and 42 with the contact surface 33rd Die Ends 39 are compressed in the end positions in each case by the angle α of any size. The angle α is preferably 7 ° - 8 °. The pressure piece 43 with the contact surfaces 33 is welded to an inner ring 44.

FIG. 11 shows a detail of an inner ring 44, on which a pressure piece 46 is snapped and held by at least one snap element 38. The snap element 38 is for example a snap board or the snap elements are snap-in lugs. Alternatively, the pressure piece 46 is sprayed.

FIGS. 12 and 13 show inner rings 47 and 48, on whose material the contact surfaces 33 are formed directly on a radial board 49 and 50. The inner ring 47 also has integrally formed with the inner ring 47 axial extensions 51 for the positive engagement between the spring tongues of a plate spring. The inner ring 48 is a forming part, which is produced for example by combined methods of deep drawing, pressing and or rolling and embossing. LIST OF REFERENCE NUMBERS

Toroidal body 29 bearing ring

Grid line 30 contact surface

Grid line 31 chamfer

Mantle line 32 pressure piece

Rotation axis 33 contact surface

Surface 34 extension

Line contact 35 curvature

Arrow 36 inner ring

Contact 37 pressure piece

Contact 38 snap element

Arrow 39 End of a spring tongue

Point 40 spring tongue

Contact surface - 41 line contact

Cylinder 42 line contact

Circle / circle level 43 pressure piece

Rotation axis 44 inner ring

Center 45 inner ring

Mantellie 46 pressure piece

Symmetry axis 47 Inner ring a Intersection 48 Inner ring

Circumference 49 Radial board

Crest line 50 Radial board

Clutch release bearing 51 extension

outer ring

inner ring

roll

Cage

Ausrücklagergehäuse

shelf

approach surface

Claims

claims

1. clutch release bearing (21) in contact with a plate spring, wherein the clutch release bearing (21) at least one curved and radially to the rotational axis (4) of the clutch release bearing (21) spaced starting surface (12, 28, 30, 33) for the start of at least one end (39) at least one spring tongue (40) of the disc spring, characterized in that the contact surface (12, 28, 30, 33) by any number of mutually adjacent and parallel aligned rectilinear generatrices (17) is described, each of the Manteiiinien (17) each tangent to an imaginary circle (14) is rectilinear in alignment and while the axis of rotation (4) of the clutch release bearing (21) the circle (14) in the circle center (16) pierces vertically.

2. clutch release bearing according to claim 1, characterized in that the contact surface (12, 28, 30, 33) to the end (39) of the spring tongue (40) is convexly bulged out.

3. clutch release bearing according to claim 1, characterized in that the contact surface (12) by at least one segment of an outer circumferential surface of a cylinder (13) is described, wherein the axis of symmetry (18) of the cylinder (13) tangential to an imaginary about the rotation axis (4) is aligned extending circumferential line (19) and wherein the axis of symmetry (18) parallel to the generatrices lines (17).

4. clutch release bearing according to claim 3, characterized in that the parallel distance between the axis of symmetry (18) and each of the generatrices (17) of the contact surface (12) is at least 5mm.

5. clutch release bearing according to claim 1, characterized in that circumferentially about the axis of rotation (4) more of the Anlaufflä- Chen (12, 28, 30, 33) are arranged, wherein each of the contact surfaces (12, 28, 30, 33) is associated with at least one of the ends (39).

6. clutch release bearing according to claim 5, characterized in that the contact surfaces (30) circumferentially immediately adjacent to each other follow each other.

7. clutch release bearing according to claim 5, characterized in that the contact surfaces (33) circumferentially spaced from one another follow each other.

8. Kuppiungsausrückiager according to claim 7, characterized in that between at least two circumferentially successive of the contact surfaces (33) an axial extension (34, 51) is formed.

9. clutch release bearing according to claim 8, characterized in that the extension (34) is tapered roof-shaped in the axial direction.

10. clutch release bearing having at least one inner ring (23, 36, 44, 45, 48) and at least one row on the inner ring (23, 36, 44, 45,

48) rolling rolling element according to claim 1, characterized in that the contact surface (12, 28, 30, 33) on an axially facing end face of the inner ring (23, 36, 44, 45, 48) is formed.

11. A clutch release bearing according to claim 10, characterized in that the contact surface (28, 30, 33) on a non-cutting produced by forming from sheet metal radial plate (27, 50) of the inner ring (23, 48) is formed.

12. clutch release bearing according to claim 11, characterized in that a plurality of the contact surfaces (28, 30, 33) directly on the radial board (27, 50) are formed.

13. A clutch release bearing according to claim 10, characterized in that the contact surface (33) on at least one of the inner ring connected to the pressure piece (32, 37, 43, 46) is formed.

14. Clutch release bearing according to claim 13, characterized in that the annular pressure piece (32, 37, 43, 46) is made of plastic.

15. Clutch release bearing according to claim 14, characterized in that the plastic is a thermoplastic.

16. Clutch release bearing according to claim 13, characterized in that the pressure piece (43) is made of hard metal.

17. Clutch release bearing according to claim 11 or 13, characterized in that the contact surface (12, 28, 30, 33) is provided with a wear-resistant surface.