Cover assembly for friction clutch with disc spring centering tab

Abstract

Cover assembly (1) for a friction clutch (2), comprising a cover (3) and a disc spring (4) arranged axially offset thereto, wherein the disc spring (4) is provided for actuating a clutch disc, and the cover (3) has at least one centering tab (9) for centering the disc spring (4), wherein the centering tab (9) is specifically machined such that the material of the centering tab (9) offers greater resistance upon contact with the material of the disc spring (4) than an area (10) of the cover (3) adjacent to the centering tab (9), characterized in that a separate, hardened component (22) is incorporated into the centering tab (9), and the geometry of the hardened component (22) is dimensioned and the hardened component (22) is arranged such that the respective circumferentially (Z) facing end faces (25) of the hardened component (22) are aligned in the respective circumferential direction (Z). (Z) pointing tab mounting surfaces (16) pass over.

Description

[0001] The present invention relates to a cover assembly for a friction clutch, comprising a cover and a disc spring arranged axially offset therefrom, wherein the disc spring is provided for actuating a pressure plate, and the cover has at least one centering tab for centering the disc spring.

[0002] A friction clutch of the aforementioned type is used, for example, in automotive engineering to couple and decouple a crankshaft of an internal combustion engine with an input shaft of a manual transmission, with an output shaft of the manual transmission being rotationally connected to at least one drive gear. Typically, a clutch disc is rotationally fixed to the transmission input shaft, and the crankshaft is rotationally fixed to the cover assembly. The diaphragm spring displaces, for example, like a lever, the pressure plate for clamping the clutch disc with, for example, a pressure plate rotationally fixed to the cover assembly and the crankshaft.

[0003] For the purpose of increased repeatability during actuation, it is desirable to position the disc spring precisely relative to the cover.

[0004] For example, DE 10 2014 203 416 A1 discloses a friction clutch for coupling a drive shaft of a motor vehicle engine to a transmission input shaft of a motor vehicle transmission, comprising a counterplate for introducing a torque, a pressure plate displaceable relative to the counterplate for frictionally pressing a clutch disc to discharge the torque, a clutch cover connected to the counterplate for at least partially covering the pressure plate, a lever spring, in particular a disc spring, pivotably supported on the clutch cover for displacing the pressure plate, a servo spring, in particular designed as a lever spring, for reducing an actuating force required to displace the pressure plate and which can be applied by an actuating system in the event of wear, and a support element, in particular designed as a retaining hook and spaced from the pressure plate, for axially supporting the servo spring.The support element has a web extending in the axial direction and a support stop projecting in the radial direction and / or substantially in the tangential direction for axially engaging a first force edge of the servo spring. The lever spring has a spring opening, and the web of the support element extends through the spring opening. In a further development, at least one spacer bolt is connected to the clutch cover for axially engaging a second force edge of the servo spring, which is different from the first force edge, the spacer bolt extending, in particular, through the lever spring. It is proposed that the lever spring be centered on the spacer bolt. Furthermore, it is proposed that the spacer bolt be designed as a single piece with the clutch cover and as a component bent from the clutch cover.

[0005] The component, which is integral with the clutch cover and bent from the clutch cover, is referred to below as the tab. Centering the lever spring or disc spring on the tab is referred to as tab centering, and the tab is therefore referred to as the centering tab.

[0006] During plate centering, repeated contact occurs between the centering plate and the diaphragm spring due to rotational movements. At the same time, a relatively soft material, such as unhardened sheet steel, is used for the clutch cover, whereas a relatively hard material, such as hardened sheet metal, is used for the diaphragm spring. As a result, the centering plate wears upon repeated contact with the diaphragm spring. This wear is undesirable in itself. This wear also has the undesirable consequence of increasing the force required to actuate the friction clutch, resulting in an increase in hysteresis in an actuation force-actuation travel map. In an undesirable extreme case, the wear can not only hinder but even prevent clutch actuation.

[0007] Furthermore, from DE 34 20 109 A1 a friction clutch is known, in particular for motor vehicles, with a disc spring which is pivotally mounted on a clutch cover in that it is pivotally held between a support on the cover side and a support provided on the side of the disc spring facing away from the cover, the cover / disc spring / supports unit is held together by holding means which are punched out of the cover and folded along an at least approximately radial bending line into a plane running at least approximately in the radial direction and perpendicular to the plane of rotation of the friction clutch and which penetrate the disc spring in the axial direction, characterized in that the holding means have a radially outwardly extending extension with which they engage under the support formed by a wire ring, provided at the same radial height as the cover-side support, by means of a support zone.

[0008] Furthermore, a cover assembly is known from DE 31 41 795 A1, which can be read in the preamble of claim 1.

[0009] The present invention aims to overcome the disadvantages known from the prior art. In particular, a centering method is to be found that reduces wear when the centering tab comes into contact with the diaphragm spring. As a secondary condition, care must be taken to maintain the essential properties of the clutch cover and the diaphragm spring, such as the respective hardnesses, and to avoid, if possible, restricting the designer in the selection of these properties. The centering tab according to the invention is intended to enable an adjustable position of the diaphragm spring. Furthermore, the centering of the diaphragm spring is to be as cost-effective as possible.

[0010] This object is achieved according to the invention by a cover assembly according to claim 1.

[0011] Further developments according to the invention are claimed in the subclaims and are explained below.

[0012] When the contact surface of the centering plate is enlarged, the resistance of the centering plate material increases proportionally with the increase in the contact surface. Accordingly, wear on the centering plate material is reduced.

[0013] It is particularly cost-effective if the centering tab is machined using a non-cutting process. This is especially true for non-cutting machined covers, such as those machined by forming and / or stamping. Stamping allows for an adjustable position of the disc spring.

[0014] If a separate hardened component is attached to the centering tab, the resistance of the centering tab can be increased without making any specifications regarding the selection and / or material processing of the cover in general and the centering tab in particular.

[0015] Especially when the lid is manufactured by forming, it is advantageous to create the centering tab by folding, flanging, or upsetting, in order to form the centering tab during an existing production step for forming the lid. This saves costs.

[0016] The resistance of the centering tab material can also be increased by adding a material with an already increased resistance to the centering tab. Specifically, according to the invention, a separate hardened component is inserted into the centering tab. Or the hardened component can be attached to the centering tab. These variants have the advantage that the hardness of the separate component can be combined with the cover as required. These variants advantageously provide a high degree of design freedom with regard to the choice of material or material features of the cover.

[0017] A receptacle for the hardened component can be provided in the centering tab, for example, by inserting the hardened component into a groove or slot. This ensures a tight fit of the hardened component on the centering tab.

[0018] A firm fit of the hardened component on the centering tab is also achieved if the hardened component is placed over the centering tab, at least partially surrounding an outer contour of the centering tab.

[0019] It is particularly preferred if the hardened component is a sleeve, since the sleeve can have a large contact area with the centering tab and can accordingly be firmly connected to the (remaining) centering sleeve.

[0020] If the sleeve has a square cross-section, the complementary or opposite cross-section of the centering lug, namely a square cross-section of the centering lug, is easy to produce. On the other hand, a square cross-section of the sleeve can be used to create a flat contact area for the centering lug for the disc spring, whereby a flat contact area ultimately results in high resistance of the centering lug material when it comes into contact with the disc spring material. Due to the aforementioned advantages, the feature of a flat or planar contact surface of the centering lug can be claimed separately.

[0021] The hardened component can, in particular, be a piece of hard metal. Hard metal pieces are easy and cost-effective to manufacture.

[0022] It can further be provided that the hardened component is formed as a piece of hard metal with an outer contour or contour adjacent to the centering tab. An outer contour adjacent to the centering tab has two advantages: first, that a notch effect can be controlled and reduced, and second, that the piece of hard metal contributes to reducing manufacturing costs as a die during a forming step.

[0023] The cover assembly can also be provided with a wire ring to form a pivot bearing for the disc spring. Such a pivot bearing is cost-effective and proven. If the centering tab is also designed to center the wire ring, synergistic effects are achieved, while at the same time eliminating the need for a separate centering tab for centering the wire ring. Ultimately, the manufacturing costs for the cover assembly are further reduced.

[0024] In summary, and in other words, various possibilities are proposed for centering a disc spring in a friction clutch, such as a so-called hook clutch, using cover-side tabs or centering tabs. The hooks or hook tabs, by means of which the disc spring is held on a clutch cover so that it can be tilted or pivoted in the axial direction, possibly with the interposition of a support spring or sensor spring, are arranged circumferentially next to the tab. According to the invention, the contact surfaces of the cover-side tab are to be enlarged, for example at the edges of centering windows of the disc spring. This can be achieved, for example, by doubling the tab, by interposing a piece of hard metal, by attaching a hard metal sleeve, or by upsetting the tab.

[0025] The invention is described below using several embodiments. They depict: Fig. 1 a plan view of a cover assembly according to a first embodiment of the invention and of attachments, Fig. 2 an enlarged view of the Fig. 1 area marked II, Fig. 3 is an enlarged partial cross-section of the cover assembly according to the first embodiment of the invention along the line III-III in Fig. 1 marked line, Fig. 4 a perspective cross-section through the cover assembly according to the first embodiment along a line marked IV-IV in Fig. 1, Fig. 5 is an enlarged, cut-out and perspective view of a cover of the cover assembly according to the first embodiment with a centering tab, Fig. 6 a representation of an intermediate step in the formation of the Fig. 5, viewed from a longitudinal axis of the cover assembly according to the first embodiment, Fig. 7 one of the Fig. 5 corresponding representation of a cover of a cover assembly according to a second embodiment of the invention with a centering tab, Fig. 8 one of the Fig. 5 corresponding representation of a cover of a cover assembly according to a third embodiment of the invention with a centering tab, Fig. 9 one of the Fig. 5 corresponding representation of a cover of a cover assembly according to a fourth embodiment of the invention with a centering tab, Fig. 10 the lid of Fig. 9 with a hard metal piece inserted into the centering tab, Fig. 11 one of the Fig. 5 corresponding representation of a cover of a cover assembly according to a fifth embodiment of the invention with a centering tab, and Fig. 12 one of the Fig. 5 corresponding representation of a cover of a cover assembly according to a sixth embodiment of the invention with a centering tab.

[0026] The figures are merely schematic and serve only to clarify the invention. The same or comparable elements are provided with the same reference numerals and will not be described again.

[0027] A first embodiment of the invention will be described below with reference to the Fig. 1-6. A cover assembly 1 of a friction clutch 2 has a cover designated as a whole by 3, a disc spring 4, and a wire ring 5. The wire ring 5 is part of a pivot bearing 6, around which the disc spring 4 can pivot. The friction clutch 2 is rotatable about a longitudinal axis X. A radial direction Y is defined perpendicular to the longitudinal axis X, and a circumferential direction Z is defined circulating around the longitudinal axis X.

[0028] Retaining tabs 7 are integrally formed on the cover 3 by means of a forming process. The retaining tabs 7 support a sensor spring 8, which, together with the wire ring 5, essentially forms the pivot bearing 6.

[0029] Centering tabs 9 are also formed on the cover 3. The centering tabs 9 are formed integrally with the cover 3.

[0030] A lid main section 10 of the lid 3 extends essentially in a radial plane around the main longitudinal axis X. Each centering tab 9 has a connecting section 11, which protrudes radially inward from the lid main section 10. The connecting section 11 is bent in the direction of the longitudinal axis X. A tab main section 12 adjoins the connecting section 11.

[0031] In the first embodiment, the main tab section 12 has a first axially oriented section 13, a bent section 14, and a second axially oriented section 15. The first axially oriented section 13 preferably directly adjoins the connecting section 11 and extends substantially parallel to the longitudinal axis X. The bent section 14 preferably directly adjoins the first axially oriented section and is bent radially, preferably radially inward, by approximately 180 degrees. The second axially oriented section 15 preferably directly adjoins the bent section 14 and extends substantially parallel to the longitudinal axis X. The first axially oriented section 13, the bent section 14, and the second axially oriented section 15 have two common tab contact surfaces 16, each located at the end in the circumferential direction.The tab contact surfaces 16 are formed by punching, spaced apart from each other by a predetermined width (not shown) in the circumferential direction Z. This width allows for a particularly well-adjustable position of the disc spring 4.

[0032] The main plate section 12 protrudes through a spring window 17 of the disc spring 4. The spring window 17 is formed, for example, between two disc spring tongues 19 of the disc spring 4, which project radially inward from a force edge 18 of the disc spring 4. The spring window 17 defines at least two disc spring contact surfaces 20, which point from the respective disc spring tongue 19 essentially in the circumferential direction Z. The spring contact surfaces 20 are adjacent to the respective plate contact surface 16.

[0033] The respective tab contact surface 16 and the adjacent disc spring contact surface 20 are arranged and designed such that they can be brought into contact in pairs upon rotation of the disc spring 4 in the circumferential direction Z. It is preferred if these can be brought into contact with one another in pairs over a flat surface.

[0034] When the tab contact surface 16 and the respective disc spring contact surface 20 come into contact, a resistance of the centering tab 9 results from at least two properties, namely firstly global properties of the cover 3 and secondly local properties of the centering tab 9.

[0035] The term "global properties" refers to all properties that affect the entire part. The global properties of the entire part include material properties, such as material properties, or properties resulting from processing the entire part, such as heat treatment measures, such as toughness. The entire part is the cover 3 with the main cover section 10, the retaining tabs 7, and the centering tabs 9. The global properties of the cover 3 are evenly distributed in the main cover section 10 and the centering tab 9.

[0036] The term "local properties" also refers to all properties that affect the area of ​​the part. The local properties of the area include properties resulting from processing of the area, such as forming steps, such as hardening, or geometric properties, such as a notch shape factor. The area is the centering tab 9. In the first embodiment, the local properties of the centering tab 9 result from the two parallel sections lying next to one another: the first axially oriented section 13 and the second axially oriented section 15.

[0037] The centering tab 9 is therefore specifically machined in such a way that the material of the centering tab 9, when it comes into contact with the material of the disc spring 4, offers greater resistance than an area of ​​the cover 3 adjacent to the centering tabs 9, namely the main cover section 10. More precisely, the contact surface 16 of the centering tab 16 is enlarged.

[0038] In the Fig. 6 shows an intermediate step in the manufacture of the centering tab 9. Namely, the tab main section 12 is bent axially in the direction of the longitudinal axis X to form the connecting section 11. In the Fig. However, in the state shown in Figure 6, the axially oriented sections 13, 15 are not yet finally formed by forming the surrounding section 14.

[0039] Since the centering tab 9 is formed by forming, it is machined without cutting. Furthermore, the centering tab 9 is formed by folding, namely during the formation of the connecting section 11 and the bent section 13.

[0040] The first embodiment of the invention can be summarized as a forming of the centering tab 9, wherein the width dimension of the centering tab 9 is predetermined by the design, the deviation of which should be as small as possible.

[0041] A second embodiment of the invention is described below with reference to Fig. 7. The same elements or comparable elements as in the first embodiment are provided with the same reference numerals and will not be described again.

[0042] In the second embodiment of the invention, a separate, hardened component 22 is inserted into a groove 21, which extends in the radial and axial direction between the first axially oriented section 13 and the second axially oriented section 15. The hardened component 22 is preferably a piece of hard metal, but can also be made of any other material. A thickness of the hardened component 22 corresponds to a thickness of the groove 21. The groove 21 can also be referred to as a gap or slot. The hardened component 22, if it is made thicker, can also be pressed into the gap. Other joining methods such as welding or forming are also conceivable. Gluing the component in place is also possible as a variant.

[0043] The bent section 14 has an inner contour 23. An outer contour 24 of the hardened component 22 preferably abuts the inner contour 23. The inner contour 23 can also be referred to as an inner radius, inner diameter, rounding, or the like, and the outer contour 24 can also be referred to as an outer radius, outer diameter, rounding, or the like. Based on this understanding, it can be stated that the outer radius 24 of the hardened component 22 is formed such that it corresponds to the inner radius 23 of the bent section 14 or the centering tab 9. A different contour is also conceivable, as long as the additional component can be held stably in its position.

[0044] The centering tab 9 according to the second embodiment of the invention can be manufactured, for example, as follows. In a first step, a blank of the centering tab 9 or the cover 3 is produced, for example, by punching. Then, in a second step, the connecting section 11 is produced by bending, so that one of the Fig. 6 results. Then, in a third step, the hardened component 22 is pressed against a section or region of the main tab section 12 adjacent to the connecting section 11. This section adjacent to the connecting section 11 will become the first axially oriented section 13. Then, in a fourth step, the “protruding” section or region of the main tab section 12 is bent. This bending point becomes the bent section 14. In the process, the main tab section 12 is formed, preferably finally. More precisely, the first axially oriented section 13, the bent section 14 and the second axially oriented section 15 are preferably finally formed. During the fourth step, the hardened component 22 is clamped between the axially oriented sections 13, 15.The second step can also be referred to as a first bending step, and the fourth step can also be referred to as a second bending step. The four steps do not necessarily have to be separate and do not necessarily have to occur in this order. Further and / or different steps are possible. For example, the centering tab 9 can be positioned over a die after punching before the centering tab 9 is finally formed by the hardened component 22, which acts as a punch, being pressed into the die.

[0045] A geometry of the hardened component 22 is dimensioned according to the invention and the hardened component 22 is arranged according to the invention such that respective end faces 25 of the hardened component 22 pointing in the circumferential direction Z merge into the respective tab contact surface 16 pointing in the circumferential direction Z, preferably continuously in the radial direction Y and preferably with a continuous curvature in the radial direction Y or particularly preferably without curvature.

[0046] Thus, the resistance of the centering tab 9 is increased because the contact surface 16 of the centering tab 9 results from twice the thickness of the cover material and once the thickness of the hardened component 21. Thus, the contact surface 16 of the centering tab 9 is enlarged. Due to tolerances, it would also be conceivable for the hardened component to be longer than the tab is wide, so that it protrudes beyond the tab on both sides and consequently only the additional component is in contact with the disc spring.

[0047] Since the centering tab 9 is formed by forming, the centering tab 9 is machined without cutting. Furthermore, the centering tab is formed by folding, namely during the formation of the connecting section 11 and the bent section 13. The separate, hardened component 22 is inserted into the centering tab 9 or attached to the centering tab 9 according to the above description, specifically the hardened component 22 is inserted into the groove 21. The hardened component 22 is preferably designed as a hard metal piece. The hardened component 22 preferably bears against the centering tab 9 with an outer contour 24.

[0048] Otherwise, the description of the first embodiment applies.

[0049] The second embodiment of the invention can be summarized as follows: a reshaping of the centering tab 9 is proposed, wherein the centering tab 9 has a predetermined width dimension, wherein a deviation of the width dimension should be as small as possible, and wherein a hard metal piece 22 is attached to the centering tab 9.

[0050] A third embodiment of the invention is described below with reference to Fig. 8. The same or comparable elements as in the first and / or second embodiment are provided with the same reference numerals and will not be described again.

[0051] The separate, hardened component 22 is attached to the centering tab 9. The hardened component 22 is slipped over the centering tab 9, surrounding an outer contour 26 of the centering tab 9. In this case, the hardened component 22 is a sleeve 27. The sleeve 27 has a square cross-section. More precisely, the sleeve 27 has a rectangular cross-section. The sleeve 27 forms the tab contact surfaces 16 at each end in the circumferential direction Z. The hardened component can also be made of any other material. Likewise, the shape of this component can deviate from the shape shown here. In the third embodiment, the main tab section 12 comprises only the first axially oriented section 13.

[0052] The contact surface 16 of the centering tab 9 is thus enlarged by at least twice the wall thickness of the sleeve 27. The centering tab 9 is preferably machined by punching, forming, and pressing, thus without cutting. The separate, hardened component 22 is attached to the centering tab 9 as described above, namely by the hardened component 22 being slipped over the centering tab 9, at least partially surrounding the outer contour 26 of the centering tab 9. The hardened component 22 is the sleeve 27, which has a square or any other cross-section.

[0053] In a modification of the third embodiment (not shown in the figure), the main tab portion 12 comprises, as in the first embodiment, the first axially oriented portion 13, the surrounding portion 14, and the second axially oriented portion 15, and the sleeve 27 is slipped over the main tab portion 12. The modification of the third embodiment has a tab contact surface 16 that is even larger than in the third embodiment.

[0054] The centering tab 9 can therefore also be formed by folding.

[0055] Otherwise, what has been described for the first and / or second embodiment applies.

[0056] The third embodiment of the invention can therefore be summarized as follows: the sleeve 27, which is made of a hard metal, for example, is fastened to / on the centering tab 9.

[0057] A fourth embodiment of the invention is described below with reference to Fig. 9 to 10. The same or comparable elements as in one of the embodiments one to three are provided with the same reference numerals and will not be described again.

[0058] In the fourth embodiment of the invention, a forked section 28 adjoins the connecting section 11 in the axial direction. The forked section 28 connects the first axially oriented section 13, the second axially oriented section 15, and the connecting section 11 to one another. The groove 21 is located between the axially oriented sections 13, 15. The groove 21 can also be referred to as a gap or slot. The separate, hardened component 22 can be inserted into the groove 21 in the axial direction. The opening direction or mouth direction of the groove 21 along the longitudinal axis X is opposite to the opening or mouth direction of the groove 21 according to the first embodiment.

[0059] The groove 21 can be produced, for example, by driving a cutting edge (not shown) into the main tab section 12 after bending the connecting section 11, which cutting edge radially offsets and / or exposes the axially oriented sections 13, 15.

[0060] The contact surface 16 of the centering tab 9 is thus enlarged by at least the width of the groove 21. The centering tab 9 is preferably machined by punching, forming, and pressing, thus without cutting. The separate, hardened component 22 is inserted into the centering tab 9 or attached to the centering tab 9 by inserting the hardened component 22 into the groove 21. Here, too, the material and shape can be designed as desired. As in the second embodiment, the additional component can be made longer than the tab is wide.

[0061] According to a modification of the fourth embodiment (not shown in the figure), the groove 21 has the inner contour 23 of the centering tab 9, and the hardened component 22 has the outer contour 24. The properties correspond to those described in the first embodiment. Thus, the hardened component 22 can be formed as a hard metal piece with an outer contour 24 adjacent to the centering tab 9.

[0062] Otherwise, what has been described for embodiments one to three applies.

[0063] A fifth embodiment of the invention is described below with reference to Fig. 11. The same elements or comparable elements as in one of the embodiments one to four are provided with the same reference numerals and will not be described again.

[0064] The centering tab 9 of the cover 3 of the cover assembly 1 according to the fifth embodiment of the invention has the connecting section 11, to which the main tab section 12 is axially oriented or extending. A lower surface 29 of the centering tab 9 faces the connecting section 11 on the main tab section 12.

[0065] A final shape of the centering tab 9 according to the fifth embodiment is formed by a die (not shown) surrounding at least the contact surfaces 16 of the tab main body 12 before a punch presses against the surface 29 and compresses the tab main portion 12. This compression achieves two effects.

[0066] On the one hand, the material of the tab main section 12 is solidified so that the material of the cover 3, which forms the centering tab 9, has a higher resistance when coming into contact with the material of the disc spring 4 than an area of ​​the cover adjacent to the centering tab 9, such as the cover main section 10.

[0067] On the other hand, the main section 12 of the tab is widened in the radial direction Y, so that the material of the cover 3, which forms the centering tab 9, has an even higher resistance when coming into contact with the material of the disc spring 4 than an area of ​​the cover adjacent to the centering tab 9, such as the main section 10 of the cover.

[0068] The contact surface 16 of the centering tab 9 is thus enlarged, namely by the amount of the compressed material. The centering tab is machined by punching and forming, in particular by upsetting, and is thus machined without cutting.

[0069] Otherwise, what has been described for embodiments one to four applies.

[0070] The fifth embodiment of the invention can be summarized as follows, namely that the centering tab 9 is compressed in the axial direction so that the contact surfaces 16 are enlarged in the radial direction.

[0071] A sixth embodiment of the invention is described below with reference to Fig. 12. The same elements or comparable elements as in one of the embodiments one to five are provided with the same reference numerals and will not be described again.

[0072] The centering tab 9 of the cover 3 of the cover assembly 1 according to the sixth embodiment of the invention has the connecting section 11 and the main tab section 12. The main tab section 12 is originally formed as a blank (not shown) with an oversize in the circumferential direction Z. The centering tab 9 is given its final shape by two punches (not shown) preferably simultaneously or synchronously pressing against the blank in the circumferential direction Z, thereby forming the contact surfaces 16. Firstly, this results in the contact surfaces 16 having a greater thickness in the radial direction Y than the thickness of the remaining centering tab 9 or the area of ​​the cover 3 adjacent to the centering tab 9, such as the main lid section 10. Secondly, this results in the centering tab 9 being hardened at least in the area of ​​the contact surface 16, and preferably in the area of ​​the entire main tab section 12.

[0073] The contact surface 16 of the centering tab 9 is thus enlarged, namely by the amount of the compressed material. The centering tab 9 is machined by punching and forming, in particular by compression, and is thus machined without cutting.

[0074] Otherwise, what has been described for embodiments 1 to 5 applies.

[0075] The sixth embodiment of the invention can be summarized as follows, namely that the centering tab 9 is compressed in the circumferential direction so that the contact surfaces 16 are enlarged in the radial direction. List of reference symbols 1 cover assembly 2 friction clutch 3 lids 4 disc spring 5 wire ring 6 swivel bearings 7 Retaining tab 8 Sensor spring 9 Centering tab 10 Main cover section 11 Connection section of the centering tab 12 Main section of the link 13 first axially oriented section 14 Turnaround section 15 second axially oriented section 16 Tab contact surface 17 spring windows 18 Power edge 19 Disc spring tongue 20 Disc spring contact surface 21 gutter 22 hardened component 23 Inner contour of the bent section of the centering tab 24 Outer contour of the hardened component 25 Front side of the hardened component 26 Outer contour of the centering tab 27 sleeve 28 Fork section 29 Surface X Longitudinal axis Y radial direction Z circumferential direction

Claims

[1] Cover assembly (1) for a friction clutch (2), with a cover (3) and a disc spring (4) arranged axially offset therefrom, wherein the disc spring (4) is provided for actuating a clutch disc, and the cover (3) has at least one centering tab (9) for centering the disc spring (4), wherein the centering tab (9) is specifically machined such that the material of the centering tab (9) offers a higher resistance when coming into contact with the material of the disc spring (4) than an area (10) of the cover (3) adjacent to the centering tab (9), characterized by that a separate, hardened component (22) is introduced into the centering tab (9), and a geometry of the hardened component (22) is dimensioned and the hardened component (22) is arranged such that respective end faces (25) of the hardened component (22) pointing in the circumferential direction (Z) merge into the respective tab contact surfaces (16) pointing in the circumferential direction (Z). [2] Cover assembly (1) according to claim 1, characterized by that a contact surface (16) of the centering tab (9) is enlarged. [3] Cover assembly (1) according to claim 1 or 2, characterized by that the centering tab (9) is machined without cutting. [4] Cover assembly (1) according to one of claims 1 to 3, characterized by that the centering tab (9) is formed by folding or by upsetting. [5] Cover assembly (1) according to one of claims 1 to 4, characterized by that the hardened component (22) is placed in a groove (21), a trough or a slot. [6] Cover assembly (1) according to one of claims 1 to 5, characterized by that the hardened component (22) is formed as a hard metal piece with an outer contour (24) adjacent to the centering tab (9).

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