SYSTEM CONSISTING OF CLUTCH DISC OR FRICTION DISC AND CLUTCH BELL TO EFFECT NOISE OPTIMIZATION

Description

[0001] The present invention relates to a system comprising a clutch disc or friction disc and a clutch bell for achieving noise optimization.

[0002] Commercial vehicles have compressed air consumers, such as a pneumatic braking system, an air suspension system, or a pneumatic clutch. A compressed air generator, such as a compressor, is provided for these compressed air consumers. Such a compressor is typically driven by the vehicle engine, for example, by a commercial vehicle's internal combustion engine.

[0003] Commercial vehicles also have compressed air reservoirs. These reservoirs temporarily store the compressed air generated by a compressed air generator until it is used by a compressed air consumer.

[0004] When a compressed air reservoir is filled with compressed air to a corresponding cut-off pressure, the compressed air generator is temporarily disconnected from its drive according to the state of the art to save energy. Such decoupling is achieved by means of a multi-plate clutch, which is installed between the vehicle engine and the compressed air generator to interrupt and restore the torque transmission.

[0005] For this purpose, this multi-plate clutch is designed in such a way that torque transmission between a radially outer clutch bell and a radially inner shaft can be established and separated again by means of frictional engagement.

[0006] This frictional engagement is achieved by means of clutch discs (e.g. made of steel) and friction discs (e.g. with embossed friction lining), whereby the clutch discs engage positively and torque-tightly in the clutch bell, and the friction discs engage positively and torque-tightly in the shaft (although an alternative arrangement is also possible).

[0007] Oil-lubricated (wet-running) multi-plate clutches according to the prior art, as already described in the introduction, comprise a clutch bell housing and clutch discs that transmit torque with the clutch bell housing by means of positive engagement. For this purpose, the clutch discs have radially outwardly projecting teeth on their circumference, with the clutch bell housing having grooves on its inner surface for receiving the teeth. Alternatively, according to the "reverse arrangement," the friction discs (instead of the clutch discs) transmit torque with the clutch bell housing by means of positive engagement, and the clutch discs (instead of the friction discs) transmit torque with the shaft by means of positive engagement.

[0008] In this context, for example, JP 2009 144890 A discloses the provision of a friction clutch device that prevents or reduces damage to an intermediate disc and has high power transmission performance and a longer service life.

[0009] EP 3 181 932 A1 relates to a clutch arrangement with an input element and with an output element connected in a rotationally fixed manner to a clutch bell housing, with a clutch pack arranged within the clutch bell housing between the input element and the output element, and with a spring arrangement which acts on the clutch pack in a closed state. The clutch bell housing has a hollow cylinder provided with a hub profile on its inner circumferential surface. A first annular stop disc is arranged at an axial end region of the hollow cylinder, and a second annular stop disc is arranged at a region spaced apart from the axial end region. The hub profile of the hollow cylinder has a plurality of radially inwardly extending profile elements, such as in particular teeth or wedges, each of which has a circumferentially identical first width and the same first distance from one another.

[0010] DE 10 2015 216270 A1 also discloses a friction element carrier for a multi-disk friction clutch, comprising a rotational axis, an axial section with teeth having flanks extending in the axial and radial directions for positive engagement with friction elements, wherein each tooth forms a radial bulge on a radial inner side of the axial section, and wherein a recess is provided in each of the radially outer sections of at least some of the teeth to allow the radial passage of a fluid. Different teeth, through whose recesses different volume flows of the fluid are to be achieved, have different dimensions in the circumferential direction.

[0011] JP 2005 161422 A is directed to providing a phase adjusting method and a phase adjusting apparatus of a laminated part that efficiently and safely adjusts a phase.

[0012] In the context of this patent application, a system consisting of a clutch bell housing and clutch disc(s) is described below, wherein the clutch bell housing and clutch disc(s) engage with each other in a form-fitting and torque-resistant manner. As already described in the introduction as a "reverse arrangement," configurations are also conceivable in which the friction discs, rather than the clutch discs, engage with the clutch bell housing. For simplicity, however, only one of these two variants is described below. Nevertheless, the described features are also disclosed analogously for a friction disc according to the "reverse arrangement."

[0013] Fig. 1 shows a separating contour Tk between a clutch disc 1 (radially inside) and a clutch bell 2 (radially outside). Fig. 1an area B of the interaction between a tooth Z (of the clutch disc 1) and a groove (of the clutch bell 2) is marked with a circle, whereby this area in Fig. 1a is presented in detail.

[0014] Fig. 1a shows the above-mentioned area of ​​interaction between a tooth Z (of the clutch disc 1) and a groove N (of the clutch bell 2) in detail. The illustrated groove N of the clutch bell 2 has lateral flanks 21, 23 extending in the radial direction, as well as a radially outer circumferential edge 22 extending in the circumferential direction. The groove N is designed to receive the illustrated tooth Z of the clutch disc 1.

[0015] The tooth Z shown has lateral flanks 11, 13 running in the radial direction, as well as a radially outer circumferential edge 12 running in the circumferential direction and connecting the lateral flanks 11, 13.

[0016] Between the circumferential edge 12 of the clutch disc 1 and the lateral flanks 21, 23 of the clutch bell 2 as well as the radially outer circumferential edge 22 of the clutch bell 2, an oil return cross-section Ar is formed, which in Fig. 1a is shown hatched. The oil return cross-section in the area of ​​interaction between all teeth Z (of clutch disc 1) and all grooves (of clutch bell housing 2) is defined as the total oil return cross-section.

[0017] When such a clutch is to be disengaged, the clutch discs are not disengaged actively, but passively. To disengage the clutch, it must be ensured that the oil can flow as freely as possible between the individual clutch discs and friction discs. Since the oil in a rotating clutch is forced radially outward due to centrifugal force, the oil must be able to flow out of the spaces between the individual clutch discs and friction discs in the area of ​​the (radially outer) interaction between the teeth and grooves.

[0018] In detail, the separation of the clutch discs is achieved by axially moving the clutch discs within the clutch bell.

[0019] One problem with clutch discs and a clutch bell housing according to the state of the art is that undesirable noise occurs due to the circumferential play of the clutch discs within the clutch bell housing. This occurs particularly when the clutch is engaged and a change between "pushing and pulling operation" occurs, i.e., when the torque curve intended to drive the compressed air generator has a zero crossing. This means that although the compressed air generator is generally driven by the drive, the compressed air generator temporarily drives the drive. At this moment, a change in the clutch disc toothing within the clutch bell housing grooves occurs (illustrated by Fig. 1aThis would mean, for example, that initially surfaces 11 and 21 are in contact with each other, but after a change of the clutch disc toothing, surfaces 13 and 23 are in contact with each other), resulting in undesirable noise.

[0020] It is therefore an object of the invention to offer a clutch disc or friction disc, a clutch bell, as well as a system comprising a clutch disc or friction disc and a clutch bell for achieving noise optimization.

[0021] This problem is solved by the subject matter of the independent claim.

[0022] Preferred further training is the subject of the subclaims.

[0023] The claimed clutch disc or friction disc according to the independent claim defines and claims the component that engages the clutch bell housing in a form-fitting and torque-resistant manner, regardless of whether this component has the friction lining (according to the aforementioned "reverse arrangement") and is thus considered a friction disc or not. However, the following only discusses a claimed clutch disc. The statements made apply analogously to a claimed friction disc according to the "reverse arrangement."

[0024] Noise optimization can be achieved in particular if the grooves of a clutch bell are manufactured using a broaching process, which enables very precise production of the grooves.

[0025] In order to be able to use a broaching process, such a clutch bell must be made of several parts and have a separate cylindrical base body, with grooves being introduced into the inside of the cylindrical base body by means of a broaching process.

[0026] A clutch disc considered here has large and small teeth, with each tooth having a specific distance between its lateral flanks (=tooth width). The tooth width of a large tooth is defined as "ZSg," and the tooth width of a small tooth as "ZSk."

[0027] Furthermore, the clutch bell housing considered here has a groove for each tooth of the clutch disc: a large groove for each large tooth, and a small groove for each small tooth. Each groove has a specific distance between its lateral flanks (=groove width). The groove width of a large groove is defined as "NSg," and the groove width of a small groove as "NSk."

[0028] Furthermore, the clutch bell preferably has additional grooves that do not accommodate a tooth in order to increase the oil return cross-section.

[0029] Tests have surprisingly shown that the dimensions of the teeth of a clutch disc or friction disc and the grooves of the clutch bell housing are crucial for achieving noise optimization. The following table shows the ranges of tooth and groove widths, along with the resulting noise levels. ZSk [mm] ZSg [mm] NSk [mm] NSg [mm] Sounds 5,5 - 6,0 9,0 - 9,5 6,0, - 6,5 9,5 - 10,0 bad 6,0 - 6,5 9,5 - 10,0 6,5 - 7,0 10,0 - 10,5 bad 6,5 - 7,0 10,0 - 10,5 7,0 - 7,5 10,5 - 11,0 optimal 7,0 - 7,5 10,5 - 11,0 7,5 - 8,0 11,0 - 11,5 bad 7,5 - 8,0 11,0 - 11,5 8,0 - 8,5 11,5 - 12,0 bad

[0030] The middle row with "optimal noise" shows the preferred dimensions for tooth and groove width to achieve noise optimization.

[0031] As described above, a clutch disc has a plurality of radially outwardly projecting teeth with lateral flanks for transmitting torque between the clutch disc and a clutch bell. The clutch disc further has circumferentially extending, radially outward peripheral edges connecting the lateral flanks of each tooth.

[0032] Furthermore, the clutch bell housing has lateral flanks for transmitting torque between it and the clutch disc. Furthermore, the clutch bell housing has radially outer, i.e., radially inwardly directed, circumferential edges that connect its lateral flanks. A single groove of the clutch bell housing is formed by two lateral flanks and a radially outer circumferential edge connecting these flanks.

[0033] When assembled, the teeth of the clutch disc are located within the grooves of the clutch bell housing. An oil return cross-section is formed between each groove containing a tooth and that tooth. Furthermore, an oil return cross-section is also formed through each groove that does not contain a tooth. The sum of all oil return cross-sections is referred to as the total oil return cross-section.

[0034] An oil return cross-section is formed between a groove containing a tooth and this tooth, as described below. A cross-section is formed between the radially outer peripheral edge of the tooth and the lateral flanks of the groove, as well as the radially outer peripheral edge of the groove, which is considered the oil return cross-section.

[0035] Preferably, a recess is provided in the radially outer peripheral edge of at least one tooth of the clutch disc in order to increase the oil return cross-section between this tooth and the groove in which it is located.

[0036] As a result, the contact area of ​​the lateral flanks of the tooth and groove is not reduced despite an increase in the oil return cross-section, which means that the clutch discs separate more quickly without any deterioration in wear.

[0037] This reduces the drag power of a clutch without increasing wear.

[0038] Furthermore, providing a recess in a clutch disc is more cost-effective than in a clutch bell, thus reducing manufacturing costs.

[0039] By forming the recess in an arc shape, the increase in the oil return cross-section is maximized while simultaneously minimizing material stresses.

[0040] Preferably, not just a single tooth of the clutch disc has a recess, but rather several teeth of the clutch disc. Preferably, the teeth having a recess are arranged opposite one another.

[0041] Preferably, all teeth of the clutch disc have a recess.

[0042] Preferably, all grooves of a clutch bell housing are filled by a clutch disc tooth. At least one of these teeth has a recess. This minimizes wear despite increasing the overall oil return cross-section.

[0043] Alternatively, according to another preferred embodiment, in addition to a clutch disc having at least one tooth with a recess, at least one tooth is also "omitted." This means that, due to this at least one omitted tooth, at least one groove of the clutch bell housing is not filled by a tooth. This also increases the overall oil return cross-section.

[0044] Preferably, a system consisting of a clutch bell and clutch discs has exactly three clutch discs. Fig. 1 shows a separating contour Tk between a clutch disc 1 and a clutch bell 2. Fig. 1a shows an enlarged section B of Fig. 1. Fig. 2 shows a separating contour Tk between a clutch disc 1 and a clutch bell 2. Fig. 3 shows a separating contour Tk between a clutch disc 1 and a clutch bell 2. Fig. 4 shows a clutch disc 1 in interaction with a clutch bell 2. Fig. 4a shows an enlarged section C from Fig. 4 . Fig. 5 shows a separating contour Tk between a clutch disc 1 and a clutch bell 2. Fig. 6 shows tooth widths ZSg, ZSk and groove widths NSg, NSk.

[0045] The Figs. 1 and 1a were already acknowledged in the introduction to the description.

[0046] Fig. 2 shows a separating contour Tk between a clutch disc 1 and a clutch bell 2 according to an embodiment. In comparison to Fig. 1The separating contour Tk differs only in that two teeth Zx, shown here in black, are omitted from the design. An omitted tooth Zx represents a groove in the clutch bell housing 2 in which no tooth is located when the clutch disc 1 is mounted.

[0047] Furthermore, the Fig. 2 The construction shown differs from that shown in Fig. 1 or in Fig. 1a shown construction that all teeth Z* in Fig. 2 have a recess, as detailed in Fig. 4 shown.

[0048] Fig. 3 shows analogous to Fig. 2 a separating contour Tk between a clutch disc 1 and a clutch bell 2 according to an embodiment. In the Fig. 3 In the embodiment shown, four teeth Zx, shown in black, are omitted from the design, in contrast to two omitted teeth Zx in Fig. 2. Other differences lie between the designs of the Figs. 2 and 3 not present.

[0049] Fig. 4 shows again the clutch disc 1 from Fig. 3 , compared to the Fig. 1 , 2 and 3 However, the separating contour between clutch disc 1 and clutch bell 2 is not merely shown schematically. Rather, Fig. 4 Teeth Z* can be identified by their recesses, whereby these recesses are described in the following Fig. 4a with reference to section C (see Fig. 4 ) will be explained in detail.

[0050] All teeth in Fig. 4 The clutch disc 1 shown also has a recess.

[0051] Fig. 4a shows analogous to Fig. 1aThe above-mentioned area (section C) of the interaction between a tooth Z* (of the clutch disc 1) and a groove N (of the clutch bell 2) in detail. The illustrated groove N of the clutch bell 2 has lateral flanks 21, 23 extending in the radial direction, as well as a radially outer, circumferential edge 22 extending in the circumferential direction. The groove N is designed to receive the illustrated tooth Z* of the clutch disc 1.

[0052] The circumferential direction in this detailed view corresponds to the horizontal direction in Fig. 4a , where the radial direction is the vertical direction in Fig. 4a The same applies to Fig. 1a analogue.

[0053] The tooth Z* shown has lateral flanks 11, 13 running in the radial direction, as well as a radially outer circumferential edge 12 running in the circumferential direction, which is, however, interrupted by a recess 12*.

[0054] An (enlarged) oil return cross-section Ar* is formed between the two-part circumferential edge 12 and the recess 12* of the clutch disc 1 and the lateral flanks 21, 23 of the clutch bell housing 2, as well as the radially outer circumferential edge 22 of the clutch bell housing 2, which is shown hatched. The oil return cross-section in the area of ​​the interaction between all teeth Z (of the clutch disc 1) and all grooves N (of the clutch bell housing 2) is defined as the total oil return cross-section. If teeth have been omitted as described above, the total oil return cross-section is further increased.

[0055] The recess 12* is arcuate in this embodiment. Furthermore, the recess 12* is arranged in this embodiment such that the lateral flanks 11, 13 are not shortened by the recess 12*. This means that the recess 12* does not intersect the lateral flanks 11, 13.

[0056] According to a further embodiment not shown, the recess 12* is indeed curved, but is not necessarily arranged in such a way that the lateral flanks 11, 13 are not shortened by the recess 12*.

[0057] According to a further embodiment not shown, the recess 12* is not necessarily curved, but is arranged such that the lateral flanks 11, 13 are not shortened by the recess 12*.

[0058] The remaining features of these two variations correspond to those described with reference to the Figs. 4 and 4a described characteristics.

[0059] Fig. 5shows a separating contour Tk between clutch disc 1 and clutch bell housing 2 to illustrate an arrangement of teeth Zg (=large teeth) and Zk (=small teeth) within grooves of clutch bell housing 2. For better clarity, the grooves of clutch bell housing 2 have not been labeled in this illustration; however, each large tooth Zg is accommodated by a groove Ng (=large groove, not labeled), and each small tooth Zk by a groove Nk (=small groove, not labeled). In addition, clutch disc 1 has four "omitted teeth" Zx, shown here in black. This means that although clutch bell housing 2 has a groove at each of these locations, clutch disc 1 has no teeth, leaving these grooves unfilled.

[0060] The large teeth Zg, which in this embodiment are arranged opposite each other (here: top / bottom), form an axis of symmetry Y, with the small teeth Zk being arranged around the circumference of the clutch disc 1 in such a way that an axial symmetry is established with respect to the axis of symmetry Y. The same applies analogously to the grooves of the clutch bell 2.

[0061] In this embodiment, the small teeth Zk are arranged at an angular spacing of a = (360 / 22) degrees. The same applies analogously to the grooves of clutch bell housing 2.

[0062] Fig. 6 shows analogous to the above Figures 1a and 4a an interaction between a tooth and a groove to illustrate the dimensions of teeth and grooves, especially tooth width and groove width.

[0063] In the above Fig. 5 Large teeth Zg and small teeth Zk were described, which have different tooth widths. Nevertheless, Fig. 6the measurements for large and small teeth are explained (for illustration purposes) using a single tooth, although it is clear that these teeth have different widths in reality.

[0064] Both a small tooth Zk and a large tooth Zg each have lateral flanks 11, 13. The distance between these flanks 11, 13 defines the tooth width. A small tooth Zk has a width of ZSk, and a large tooth Zg has a width of ZSg.

[0065] Each large tooth Zg of the clutch disc 1 is received by a large groove Ng of the clutch bell 2, the same applies to each small tooth Zk of the clutch disc 1, which is received by a small groove Nk of the clutch bell 2.

[0066] Both a small groove Nk and a large groove Ng each have lateral flanks 21, 23. The distance between these flanks 21, 23 defines the groove width. A small groove Nk has a width of NSk, and a large groove Ng has a width of NSg.

[0067] In this embodiment, the circumferential edges of the teeth Zg, Zk do not have any recesses to enlarge the oil return cross-section Ar.

[0068] In a further embodiment not shown, which otherwise corresponds exactly to the embodiment shown in Figs. 5 and 6 corresponds, the peripheral edges of the teeth Zg, Zk have recesses for enlarging the oil return cross-section Ar to the oil return cross-section Ar*, as in. Fig. 4a described.

[0069] The lateral flanks 21, 23 of the grooves Ng, Nk as well as the lateral flanks 11, 13 of the teeth Zg, Zk are arranged parallel to one another in the embodiments shown here.

[0070] In a further embodiment not shown, which otherwise corresponds exactly to the embodiment shown in Figs. 5 and 6 corresponds, and optionally corresponds to the above-mentioned design with recesses, these are not arranged parallel to each other, whereby the tooth and groove widths do not correspond to a fixed value, but to a fixed range of values.

Claims

1. System comprising at least a clutch disc (1) or a friction disc as well as a clutch case (2) for effecting noise optimization, wherein the clutch case (2) has a cylindrical main body with axially extending grooves (N, Ng, Nk) on the inside of the cylindrical main body, wherein the grooves (N, Ng, Nk) have lateral flanks (21, 23), the clutch disc (1) or the friction disc have a plurality of radially outwardly projecting teeth (Z, Zg, Zk) with lateral flanks (11, 13) for transmitting a torque between the clutch disc (1) and / or the friction disc and grooves (N) provided in the clutch case (2) with lateral flanks (21, 23), characterized in that at least one of the teeth (Zk) has a distance (ZSk) between the lateral flanks (11, 13), which is in a range of 6.5 mm to 7.0 mm, as a result of which a small tooth (Zk) is defined and at least one of the grooves (Nk) has a distance (NSk) between the lateral flanks (21, 23), which is in a range of 7.0 mm to 7.5 mm, as a result of which a small groove (Nk) is defined, wherein each small tooth (Zk) of a clutch disc (1) and / or friction disc is engaged in a small groove (Nk) of the clutch case (2).

2. System according to the preceding claim, wherein at least one of the teeth (Zg) has a distance (ZSg) between the lateral flanks (11, 13), which is in a range of 10.0 mm to 10.5 mm, as a result of which a large tooth (Zg) is defined.

3. System according to any one of the preceding claims, wherein the clutch disc (1) and / or friction disc has exactly two of the large teeth (Zg), which are arranged opposite one another on the circumference of the clutch disc (1) and / or friction disc.

4. System according to any one of the preceding claims, wherein the clutch disc (1) and / or friction disc has exactly sixteen of the small teeth (Zk), which are distributed on the circumference of the clutch disc (1) and / or friction disc.

5. System according to claim 2, wherein the clutch disc (1) and / or friction disc has exactly two of the large teeth (Zg), which are arranged opposite one another on the circumference of the clutch disc (1) and / or friction disc, and has exactly sixteen of the small teeth (Zk), which are distributed on the circumference of the clutch disc (1) and / or friction disc.

6. System according to the preceding claim, wherein an axis of symmetry (Y) is defined by the two large teeth (Zg), wherein eight of the small teeth (Zk) are arranged on both sides of the axis of symmetry (Y) in each case.

7. System according to the preceding claim, wherein the small teeth (Zk) are arranged on both sides of the axis of symmetry (Y) in each case at an angular distance of 360 / 22 degrees from one another, and / or the arrangement of the small teeth (Zk) is axially symmetrical relative to the axis of symmetry (Y).

8. System according to any one of the preceding claims, wherein at least one of the grooves (Ng) has a distance (NSg) between the lateral flanks (21, 23), which is in a range of 10.5 mm to 11.0 mm, as a result of which a large groove (Ng) is defined.

9. System according to any one of the preceding claims, wherein the clutch case (2) has exactly two of the large grooves (Ng), which are arranged opposite one another on the circumference of the clutch case (2).

10. System according to the preceding claim, wherein the clutch case (2) has at least sixteen of the small grooves (Nk), which are distributed on the circumference of the clutch case (2).

11. System according to claim 8, wherein the clutch case (2) has exactly two of the large grooves (Ng), which are arranged opposite one another on the circumference of the clutch case (2), and has at least sixteen of the small grooves (Nk), which are distributed on the circumference of the clutch case (2).

12. System according to the preceding claim, wherein an axis of symmetry (Y) is defined by the two large grooves (Ng), wherein eight of the small grooves (Nk) are arranged on both sides of the axis of symmetry (Y) in each case.

13. System according to the preceding claim, wherein the small grooves (Nk) are arranged on both sides of the axis of symmetry (Y) in each case at an angular distance of 360 / 22 degrees from one another, and / or the arrangement of the small grooves (Nk) is axially symmetrical relative to the axis of symmetry (Y).

14. System according to any one of claims 2 to 13, wherein each large tooth (Zg) of a clutch disc (1) and / or friction disc is engaged in a large groove (Ng) of the clutch case (2).