Abstract
A disconnect clutch for a drive train of a motor vehicle includes a torque transfer component with a contact region, an outer disc carrier, an application element, and a return spring. The outer disc carrier is rotationally and axially fixed on the torque transfer component, and arranged for receiving rotationally fixed and axially displaceable friction discs arranged for torque transmission with counter friction discs. The application element is for axially displacing at least one of the friction discs for a frictional connection and the return spring is for releasing the frictional connection. The return spring contacts the application element, the return spring comprises a radially outer portion that bears against the contact region, and the contact region is designed to modify a preload of the return spring.
Claims
1.-10. (canceled)
11. A disconnect clutch for a drive train of a motor vehicle, comprising: a torque transfer component comprising a contact region; an outer disc carrier: rotationally and axially fixed on the torque transfer component; and arranged for receiving rotationally fixed and axially displaceable friction discs arranged for torque transmission with counter friction discs; an application element for axially displacing at least one of the friction discs for a frictional connection; and a return spring for releasing the frictional connection, wherein: the return spring contacts the application element; the return spring comprises a radially outer portion that bears against the contact region; and the contact region is designed to modify a preload of the return spring.
12. The disconnect clutch of claim 11, wherein the contact region is provided by a radially outwardly projecting contact cam that is arranged for: a forming displacement during an adjustment process of a return force of the return spring; or receiving a shim.
13. The disconnect clutch of claim 12, wherein: a wedge is formed on a surface of the contact cam facing away from the friction disc; and the wedge comprises a ramp leading to a plateau extending in an axial plane.
14. The disconnect clutch of claim 12, wherein: the torque transfer component is a hub; the hub comprises a recess; and the contact cam is circumferentially adjacent to the recess.
15. The disconnect clutch of claim 14, wherein: the hub comprises a plurality of recesses with respective radially inner ends; and the plurality of recesses are aligned with one another at their radially inner ends.
16. The disconnect clutch of claim 15 wherein the radially inner ends predefine a bending range of the contact cam.
17. The disconnect clutch of claim 11, wherein the contact region is formed as a single piece or formed in multiple pieces.
18. A drive train of a motor vehicle comprising: a pair of electric motors; and the disconnect clutch of claim 11 arranged between the pair of electric motors.
19. A method for adjusting a spring force of the return spring of the disconnect clutch of claim 11, comprising: adjusting an air gap of the disconnect clutch; and axially moving a radially outer force transfer region between the torque transfer component and the return spring.
20. The method of claim 19, wherein the step of axially moving a radially outer force transfer region is effected before operation of the disconnect clutch by: bending a contact cam; or interposing a shim between a contact cam and the return spring.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] The present disclosure is further explained below with the aid of a drawing. In the figures:
[0042] FIG. 1 shows a longitudinal section through a disconnect clutch according to the disclosure,
[0043] FIG. 2 shows a perspective view of the disconnect clutch of FIG. 1, with the rivet inserted between two tabs of the return spring acting as a rotation lock,
[0044] FIG. 3 shows a longitudinal section through a section of a drive train according to the disclosure, in which the embodiment of the disconnect clutch of FIGS. 1 and 2 is inserted,
[0045] FIG. 4 shows a top view of the disconnect clutch of FIGS. 1 to 3, wherein the return feet of the return springs project into recesses in a hub so that they can be operated through a window and then snapped in behind the pressure cup feet,
[0046] FIG. 5 shows a longitudinal section along the line V of FIG. 4 at the point in time before the return spring is rotated and the engagement from behind/form fit is produced, wherein the return spring is actuated/preloaded to such an extent that the return feet of the return spring can snap in behind the pressure cup,
[0047] FIG. 6 shows a point in time during assembly after the assembly times of the FIGS. 4 and 5, at which the disconnect clutch is shown in a similar way to FIG. 4, wherein, however, the position of the return spring is now secured by a rivet after the return spring has been rotated, although a bending operation of a protruding part of a lug would also be available as an alternative,
[0048] FIG. 7 shows the disconnect clutch of FIG. 1 in a transport state which never exists in operation, wherein, due to the spring property of the return spring, it is in a force-free position in which the pressure cup is pressed against the hub, whereby a transport lock is established and the clutch can be handled as a whole,
[0049] FIG. 8 shows a more detailed longitudinal sectional view of the embodiment of the disconnect clutch of FIG. 1, wherein an air gap to be kept constant is marked as well as an offset/location/position of the return spring kept variable by bending is shown in order to allow tolerance compensation during fine adjustment of the return force,
[0050] FIG. 9 shows a section of FIG. 8 on a respective section of the hub, the return spring of the pressure pad and a shim at the time before the return spring force is set and after the return spring position has been set, wherein bending of the contact cam prevents excessive loading of the return spring during operation, but without then falling below the required minimum force, the undirected height corresponds to the maximum tolerance position, thus ensuring that bending can only ever take place in one direction, and the same force conditions always act on the return spring, i.e., the same spring load is always present, and
[0051] FIG. 10 shows a top view of the torque transfer component designed as a hub and an exposed contact cam for subsequent plasticizing/straightening of the spring force and.
[0052] The figures are only schematic in nature and serve only for comprehension of the disclosure. The same elements are provided with the same reference signs.
DETAILED DESCRIPTION
[0053] FIG. 1 shows a first embodiment of a disconnect clutch 1. The disconnect clutch 1 is designed as a multi-disc clutch 2 and has an outer disc carrier 3. The outer disc carrier 3 accommodates friction discs 4, Which are designed as steel discs 5. These interact with counter friction discs 6, which are designed as lining discs 7. The lining discs 7 are rotationally fixed to a coupling component 27 (see FIG. 3), not shown.
[0054] If there is a frictional connection between the steel discs 5 and the lining discs 7, torque is transmitted from a torque transfer component 8, which is designed as a hub 9, to the coupling component, since the outer disc carrier 3 is connected to the hub 9 by a rivet, which is only indicated here (see FIG. 1). The rivet has the reference sign 10. It realizes a riveting 11. The frictional connection is created when an application element/activation element 12 acts on the friction disc 4 closest to it, in a pressure-transmitting manner.
[0055] As soon as an air gap 13, as indicated in FIG. 8, is overcome, a complete or partial frictional connection between the friction discs 4 and the counter friction discs 6 is created for torque transmission. FIG. 1 shows the moment shortly before the frictional connection is attained. The application element 12 can be in the form of a lever or, as shown in the embodiment of FIGS. 1 to 10, can be designed as a pressure pad 14.
[0056] A return spring 15 engages through and behind the application element 12. The return spring 15 has an integral section 16, which is present at the radially inner end. This integral section 16 extends at least in sections in the circumferential direction, which can be seen well in FIG. 2. This integral section 16 thus form's a return foot. It could also be said that the integral section 16 forms a hook 17.
[0057] In FIGS. 1 and 2, it can be seen that when the return spring 15 is screwed in/rotated in the circumferential direction after assembly, that hook 17 has come into contact with the pressure pad feet/pressure pad tabs relative to the application element 12/pressure pad 14. An engagement from behind is forced. This effects a form fit between the return spring 15 and the pressure pad 14. The return spring 15 shown in FIG. 1 is already preloaded and rests with its radially outer side against a contact region 19 of the hub 9 in the region of the riveting 11.
[0058] However, at least three of the rivets 10 have a special role in that they provide a rotation lock 20 between the return spring 15 and the hub 9. At least three of the rivets 10 engage exactly between two radially outer tabs 21 of the return spring 15 in order to realize a flank centering. In the present embodiment, six such special rivets 10 are used, which entail said flank centering.
[0059] In addition to the disconnect clutch 1, FIG. 3 also shows a suitable engagement system 22. This engagement system 22 can employ a piston 23 that engages a shim 24 to mate the installation position of the disconnect clutch 1 with the installation position of the engagement system 22. An actuating bearing 25 is axially displaced from the piston 23 via the shim 24, wherein the actuating bearing 25 then engages the application element 12 in an axially displaced manner. If the air gap 13 is then overcome, a stack of discs 26 composed of the friction discs 4 and counter friction discs 6 reaches a state in which it can transmit torque. The air gap 13 is set when the disconnect clutch 1 is in the set state, as shown in FIG. 3.
[0060] While in the FIGS. 4 and 5, the return spring 15 is not yet in a form fit, in particular in contact with the pressure pad 14 in the region of the hook 17, in FIG. 6 the return spring 15 is already rotated into its operating position and the hook 17 at the free end of the integral section 16 of the return spring 15 is in engagement from behind with a pressure pad foot/tab 18 of the pressure pad 14. This condition was achieved by rotating the return spring in the direction of arrow 28.
[0061] Looking at FIG. 6, it is noticeable that only every second rivet, viewed in the circumferential direction, implements the rotation lock 20, whereas every first rivet 10 only serves to fasten the outer disc carrier 3 to the torque transfer component 8.
[0062] In FIG. 7, the pressure pad 14 is in contact with the hub 9. The contact region 19 is provided by a contact cam 29. The state shown in FIG. 7 only occurs before operation, in the transport state, namely when a transport lock is implemented. The return spring 15 then positions such that the pressure pad 14 rests against the hub 9. However, it is not completely powerless even in this state. In operation, however, no contact of the pressure pad 14 with the hub 9 should occur, which is why the preload of the return spring 15 should be skillfully selected in advance. For this purpose, it is recommended that the force of the return spring be adjustable after setting the air gap 13. The distances are selected such that the return spring 15 is always under preload, even in the transport state.
[0063] In FIG. 8, as already explained, the air gap 13 to be kept constant is visualized, wherein, however, a bending of the contact cam 29 by a bending distance 30 covered during the adjustment is shown to illustrate the necessity of a positional alignment of the return spring 15. The contact cam 29 can be integral with the torque transmitting member 8 as a single piece or can be attached thereto as a separate part.
[0064] In addition, the axial position of the contact cam 29 itself can be changed during the adjustment process in the case of a single-piece design, or the axial position of a displacement part attached to the hub can be changed in the case of a multi-part design.
[0065] This bending distance 30 allows the return spring 15 to be adjusted after shims 24 have been used (see FIG. 9). By bending, a narrowed tolerance in relation to the return force is achieved here. A height difference 31 is achieved by using shims 24, i.e., by effecting a “shimming”. Tolerances are thus compensated.
[0066] In the singular illustration of hub 9 in FIG. 10, the presence of six exposed contact cams 29 can be seen. Each contact cam 29 is delimited by two recesses 32. Inner ends of two recesses 32, adjacent to a contact cam 29, run toward one another. They define a bending range 34. If a die moves onto the contact cam 29 after performing the “shimming”, i.e., compensating for axial offsets caused by tolerances, bending can be forced in one direction to effect a position correction on the return spring 15. For screwing the return spring 15 into its end position, it is advantageous to have a wedge on the contact cam 29, which has a ramp 36 that transitions into a plateau 37. This is beneficial regarding the precision of the clutch, since the lug 21 of the return spring 15 comes into contact precisely on the plateau 37 in order to determine the axial position exactly.
REFERENCE NUMERALS
[0067] 1 Disconnect clutch [0068] 2 Multi-disc clutch [0069] 3 Outer disc carrier [0070] 4 Friction disc [0071] 5 Steel disc [0072] 6 Counter friction disc [0073] 7 Lining disc [0074] 8 Torque transfer component [0075] 9 Hub [0076] 10 Rivet [0077] 11 Riveting [0078] 12 Application element/Activation element [0079] 13 Air gap [0080] 14 Pressure pad [0081] 15 Return spring [0082] 16 Integral section [0083] 17 Hook [0084] 18 Pressure pad foot/pressure pad tab [0085] 19 Contact region [0086] 20 Rotation lock [0087] 21 Tab [0088] 22 Engagement system [0089] 23 Piston [0090] 74 Shim [0091] 25 Actuating bearing [0092] 26 Stack of discs [0093] 27 Coupling component [0094] 28 Direction of rotation [0095] 29 Contact cam [0096] 30 Bending distance [0097] 31 Height difference [0098] 32 Recess [0099] 33 Inner end [0100] 34 Bending range [0101] 35 Wedge [0102] 36 Ramp [0103] 37 Plateau
