Multi-disc brake / clutch with a wear adjustment device

Abstract

The invention relates to a multi-plate brake / clutch with a disc pack (1) and an actuator with which the disc pack (1) can be subjected to a contact pressure, and with an adjusting device (15) by means of which an excess of clearance formed in the disc pack (1) due to wear can be reduced. According to the invention, the adjusting device (15) is a ramp unit (21) formed between the disc pack (1) and the actuator (3) with at least one surface ramp (25) that is fixed to rotation about a disc brake axis and an axially adjacent rotatable surface ramp (23). When the rotatable surface ramp (23) is actuated, the ramp unit (21) expands axially by an adjustment travel (n) by compensating for the excess of clearance.

Description

[0001] The invention relates to a multi-disc brake / clutch with a wear adjustment device according to the preamble of claim 1.

[0002] A typical multi-disc brake comprises a disc assembly and an actuator that applies pressure to the disc assembly to engage the brake. The multi-disc brake also features an adjustment mechanism to reduce excessive clearance in the disc assembly caused by wear, which exceeds a factory-set nominal clearance.

[0003] DE 10 2015 201 872 A1 discloses a multi-plate clutch with an adjusting mechanism for automatically compensating for wear-related positional changes of a sliding element guided for displacement in a sliding direction. DE 26 52 060 A1 discloses a disc brake with a self-acting mechanical adjusting device comprising a spring mechanism. DE 103 51 464 A1 discloses a multi-plate brake or a multi-plate clutch comprising a mechanical adjusting device with an annular piece in conjunction with a spring.

[0004] The object of the invention is to provide a multi-disc brake / clutch in which an automatic adjustment of axial wear of the multi-disc brake / clutch can be carried out in a structurally simple manner.

[0005] The problem is solved by the features of claim 1. Preferred embodiments of the invention are disclosed in the dependent claims.

[0006] The invention relates to a multi-plate brake / clutch with a plate pack and an actuator with which the plate pack can be subjected to a contact pressure. Furthermore, the multi-plate brake / clutch has an adjusting device by means of which any wear-related excess clearance in the plate pack, exceeding a factory-set nominal clearance, can be reduced. According to the characterizing part of claim 1, the following measures are taken to achieve a structurally simple and automatic adjustment of the clearance: The adjusting device has a ramp unit formed between the plate pack and the actuator. The ramp unit is designed with at least one surface ramp that is rotationally fixed about a plate brake axis and an axially adjacent rotatable surface ramp.When the rotatable surface ramp is rotated, the ramp unit expands axially by an adjustment path, thereby using up or compensating for the excess clearance and restoring the nominal clearance.

[0007] In one technical implementation, the adjusting device can have an adjusting ring arranged axially between the lamella assembly and the actuator. In this case, the rotatable surface ramp is a single, integral component of the adjusting ring, while the non-rotatable surface ramp is a single, integral component of a non-rotatable fixed lamella of the lamella assembly.

[0008] In a space-saving design variant in the axial direction, the actuator can have a pair of discs: a fixed disc that is adjustable axially by an actuator stroke but is rotationally fixed, and a loose disc that is rotatable but not axially adjustable. A ball ramp mechanism can act between the loose disc and the fixed disc. To load the multi-disc brake / clutch, a rotary drive rotates the loose disc by a specific angle. This causes the fixed disc to adjust by the actuator stroke to exert the contact pressure on the multi-disc assembly. The fixed disc can be arranged axially adjacent to the adjusting ring, while the loose disc is positioned axially away from it, with the fixed disc interposed.

[0009] For simple rotary actuation of the adjusting ring, the adjusting device can have a ratchet mechanism with a ratchet pawl. This pawl can engage with the teeth of an adjusting ring and be guided in a circumferential direction, allowing for adjustment over a certain actuation path.

[0010] A ratchet pawl adjustment can be integrated upstream of the actual rotary adjustment ring. The ratchet pawl adjustment can be performed along the adjustment ring's toothing while the multi-plate brake / clutch is under load. In this case, the adjustment ring is pressed firmly between the plate pack and the actuator to prevent rotation. The ratchet pawl adjustment can be performed with the build-up of a spring return force.

[0011] Following the ratchet pawl adjustment, the adjusting ring rotary actuation is performed with the multi-plate brake / clutch unloaded. With the multi-plate brake / clutch unloaded, the adjusting ring is no longer pressed rotationally fixed between the disc pack and the actuator, but rather is freely rotatable. This allows the adjusting ring rotary actuation to occur, during which the ratchet pawl, which is engaged with the teeth of the adjusting ring, returns to its initial position as the spring return force dissipates. Simultaneously, the ratchet pawl rotates the adjusting ring by the actuation travel. The ramp unit expands accordingly by the adjustment travel. The ratchet pawl can preferably be mounted on the fixed disc in a circumferentially adjustable manner.

[0012] The following describes an automated ratchet pawl adjustment that is upstream of the actual adjusting ring rotary actuation: The ratchet pawl can have a driver by means of which the ratchet pawl can be coupled to a movement stop of the loose disc.

[0013] The ratchet pawl driver and the loose disc movement stop interact as follows: With a multi-plate brake / clutch set with nominal clearance (i.e., without any excess clearance), the rotary drive rotates the loose disc by a nominal angle from the unloaded state to the loaded state. During such a rotation of the loose disc beyond the nominal angle, the ratchet pawl driver remains decoupled from the loose disc movement stop.

[0014] In contrast, with a multi-disc brake / clutch featuring excessive clearance, the following situation arises: The rotary drive now rotates the loose disc by an angle from the unloaded state to the loaded state, which is an additional angle greater than the nominal angle. In this case, the ratchet pawl driver remains decoupled from the loose disc's movement stop during rotation until the nominal angle is reached. However, after exceeding the nominal angle, the loose disc's movement stop comes into contact with the ratchet pawl driver, so that the ratchet pawl adjustment is carried out, and this occurs while the multi-disc brake is closing.

[0015] After the ratchet pawl has been adjusted, it initially remains in its spring-loaded position, engaging with the adjusting ring, as the ring is pressed firmly between the clutch pack and the actuator. Only when the multi-plate brake / clutch is released towards the unloaded state is the adjusting ring free to rotate, allowing the adjusting ring to be actuated. During this actuation, the ratchet pawl, engaged with the teeth of the adjusting ring, is returned to its initial position by releasing the spring return force. Simultaneously, the adjusting ring is rotated by the actuation stroke, causing the ramp unit to expand axially by the adjustment stroke.

[0016] Exemplary embodiments of the invention are described below with reference to the accompanying figures.

[0017] They show: Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7, Fig. 8 to Fig. 9 different views, based on which the structure and function of a multi-disc brake / clutch according to the invention are described.

[0018] In the Fig. Figure 1 shows a multi-disc brake with a disc pack 1 and an actuator 3, which can be used to apply a contact pressure to the disc pack 1 in order to load the multi-disc brake. The actuator 3 has a pair of discs consisting of a fixed disc 5 and a loose disc 7, between which a ball ramp mechanism 9 ( Fig. 2 or Fig. 9) acts. The fixed disk 5 is axially adjustable by an actuator travel a, but guided in a rotationally fixed manner, while the loose disk 7 is rotatably mounted about the lamella pack axis, but is axially fixed. The loose disk 7 is actuated by means of a rotary drive 13 ( Fig. 1) can be driven. The rotary drive 13 is located in the Fig. Figure 1 shows only a toothed spindle which engages with an external tooth 11 of the loose disk 7. To load the multi-disc brake, the rotary drive rotates the loose disk 7 by an angle of rotation, so that the fixed disk 5 moves by the actuator travel a in order to exert the contact pressure on the multi-disc pack 1.

[0019] In a wear-free state, the unloaded multi-disc brake exhibits a nominal clearance. Accordingly, the rotary drive 13 rotates the loose disc 7 from the unloaded state to the loaded state by a nominal rotation angle α. N . Due to wear, an excess of the nominal clearance may occur, which can be reduced by means of an adjusting device 15 described below.

[0020] The adjusting device 15 has in the Fig. 2 an adjusting ring 17, which is arranged axially between the lamella assembly 1 and the fixed disk 5 of the actuator 3. A ramp unit 21 is formed between the adjusting ring 17 and an axially adjacent fixed lamella 19 of the lamella assembly 1. This consists of three surface ramps 23 of the adjusting ring 17 and three corresponding surface ramps 25 of the fixed lamella 19, as shown in the Fig. 3 and Fig. Figure 4 shows the adjusting ring 17. The adjusting ring 17 can be rotated by a ratchet mechanism 27 by means of an actuation travel b. When the adjusting ring 17 is rotated relative to the rotationally fixed fixed lamella 19, the ramp unit 21 expands by an adjustment travel n ( Fig. 2) axially, thereby using up the excess clearance.

[0021] The ratchet mechanism 27 has a ratchet pawl 29 which is located in the Fig. Figure 5 shows the ratchet pawl 29 in isolation. Accordingly, the ratchet pawl 29 is formed with a ratchet toothing 31, a radial spring 32, a driver 33, a return spring 35, and beveled guide tabs 37. In the installed position, the ratchet pawl 29, with its ratchet toothing 31 (spring-loaded by the radial spring 32), engages with the toothing of an adjusting ring 39. The ratchet pawl 29 is held on the fixed disk 5 by means of its beveled guide tabs 37 (and by means of a guide wall 38 formed on the adjusting ring 17). The ratchet pawl 29 is guided in a circumferentially adjustable position about the actuation travel b. In the assembled position, the guide tabs 37 of the ratchet pawl 29 project into corresponding axial recesses 36 of the fixed disk 5, of which only in the Fig. 6 an axial rebound 36 is shown.

[0022] In the, in the Fig. In the installation position shown in Figure 2, the ratchet pawl driver 33 extends axially beyond the fixed disk 5 to the loose disk 7. A movement stop 41 is formed on the inner circumference of the loose disk 7, which can be brought into contact with the ratchet pawl driver 33. The ratchet pawl driver 33, together with the return spring 35 formed thereon, is located between two projections 43 formed on the inner circumference of the loose disk ( Fig. 2) tense.

[0023] The following describes the engagement of the multi-disc brake set with a nominal clearance (i.e., without excess clearance): Accordingly, the rotary drive 13 rotates the loose disk 7 by a nominal rotation angle α. N ( Fig. 2) from the unloaded state to the loaded state. In this case, the ratchet pawl driver 33 remains stationary during the rotation of the loose pulley over the nominal rotation angle α. Nmovement decoupled from the loose disc movement stop 41. Thus, no ratchet pawl adjustment occurs via the actuation path b and therefore no adjusting ring rotation actuation by means of the ratchet mechanism 27 as well as no wear-related readjustment.

[0024] If the multi-disc brake has an excess clearance, the following situation arises: The rotary drive 13 rotates the loose disk 7 by an angle of rotation from the unloaded state to the loaded state, which is further rotated by an additional angle α Z ( Fig. 2) is greater than the nominal rotation angle α N . Until the nominal rotation angle α is reached N The ratchet pawl driver 33 remains decoupled from the loose disc movement stop 41. After exceeding the nominal rotation angle α NHowever, the loose disc movement stop 41 is coupled to the ratchet pawl driver 33. Accordingly, when the multi-disc brake is loaded, the ratchet pawl 29 adjusts itself along the adjusting ring toothing 39, for example by one tooth, while the adjusting ring 17 is pressed rotationally fixed between the disc assembly 1 and the loose disc 7 of the actuator 3. This ratchet pawl adjustment occurs by building up a spring return force, which is exerted by the return spring 35 of the ratchet pawl 29. The ratchet pawl 29 remains in its pre-tensioned position as long as the multi-disc brake is loaded.

[0025] To relieve the load on the lamellar brake, the rotary drive 13 rotates the loose disk 7 in the opposite direction, causing the fixed disk 5 to also rotate in the opposite direction by the actuator travel a ( Fig. 2) is reset. This relieves the multi-disc brake. With the multi-disc brake relieved, the adjusting ring is no longer rotationally fixed, but rather rotatably held between the disc assembly 1 and the loose disk 7 of the actuator 3. Therefore, a rotary actuation of the adjusting ring can be carried out with the aid of the ratchet mechanism 27, in which the ratchet pawl 29, which is in tooth engagement with the adjusting ring toothing 39, is returned to its initial position by releasing the spring return force, and at the same time the adjusting ring 17 is rotated by the actuation travel b, so that the ramp unit 21 expands axially by the adjustment travel n.

[0026] In the Fig. 6, Fig. 7, Fig. 8 to Fig. Figure 9 shows a multi-disc brake according to a second embodiment. Its basic design and function are approximately the same as the multi-disc brake of the first embodiment. Therefore, reference is made to the preliminary description. In contrast to the first embodiment, in the Fig. 6 and Fig. 8 The adjusting ring toothing 39 is formed directly on an inner circumferential edge of the guide wall 38 of the adjusting ring 17. The web-like radial spring 32 is positioned laterally next to a detent body via a sheet metal fold, as shown in the Fig. 7 is indicated.

[0027] In the Fig.Figure 9 shows a further view of the axial assembly consisting of the actuator 3, the adjusting ring 17, and the clutch pack 1. Accordingly, wave springs 45 are positioned between the individual clutch pack 1 plates, ensuring sufficient clearance between the plates when the brake is released. A wave spring is also positioned between the fixed disc 5 of the actuator 3 and the axially opposite fixed disc 19 of the clutch pack 1. This ensures that, when the clutch pack brake is released, the adjusting ring 17 can rotate as smoothly as possible between the fixed disc 19 and the fixed disc 5. LIST OF DESIGNATION MARKS: 1 slat package 3 Actuator 5 fixed disk 7 Lottery wheel 9 ball ramp mechanism 11 External teeth 13 Rotary drive 15 Adjustment device 17 Adjustment ring 19 Fixed slat 21 ramp units 23 surface ramps of the adjusting ring 25 surface ramps of the fixed lamella 27 Ratchet mechanism 29 ratchet handle 31 Ratchet teeth 32 Radial spring 33 drivers 35 Return spring 36 axial retraction 37 angled guide tabs 38 guide wall 39 Adjusting ring teeth 41 Movement stop 43 protrusions 4 wave springs a actuator path b. Actuation method n Adjustment path α N Nominal rotation angle α Z Additional angle QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2015 201 872 A1

[0003] DE 26 52 060 A1

[0003] DE 103 51 464 A1

[0003]

Claims

Multi-plate brake / clutch with a multi-plate pack (1) and with an actuator (3) with which the multi-plate pack (1) can be subjected to a contact pressure, and with an adjusting device (15) by means of which a wear-related excess clearance in the multi-plate pack (1) can be reduced, characterized in that the adjusting device (15) is a ramp unit (21) formed between the multi-plate pack (1) and the actuator (3) with at least one surface ramp (25) which is rotationally fixed about a multi-plate pack axis and an axially adjacent rotatable surface ramp (23), and that when the rotatable surface ramp (23) is rotated, the ramp unit (21) expands axially by an adjustment path (n) by compensating for the excess clearance. Multi-plate brake / clutch according to claim 1, characterized in that the adjusting device (15) has an adjusting ring (17) arranged axially between the multi-plate pack (1) and the actuator (3), and that the rotatable surface ramp (23) is part of the adjusting ring (17), while the non-rotatable surface ramp (25) is part of a non-rotatable fixed plate (19) of the multi-plate pack (1). Multi-disc brake / clutch according to claim 1 or 2, characterized in that the actuator (3) has a pair of discs consisting of a fixed disc (5) adjustable in the axial direction by an actuator travel (a) but not rotatable and a loose disc (7) rotatable but not axially adjustable, and that to load the multi-disc brake / clutch a rotary drive (13) rotates the loose disc (7) by an angle of rotation, so that the fixed disc (5) is adjusted by the actuator travel (a) in order to exert the contact pressure on the multi-disc pack (1). Multi-disc brake / clutch according to claim 3, characterized in that the fixed disc (5) of the actuator (3) is arranged axially adjacent to the adjusting ring (17), while the loose disc (7) of the actuator (3) is axially spaced from it with the fixed disc (5) interposed, and / or that a ball ramp mechanism (9) acts between the loose disc (7) and the fixed disc (5). Multi-plate brake / clutch according to one of claims 3 to 4, characterized in that the adjusting ring (17) is rotatable by means of the adjusting device (15), that the adjusting device (15) has a ratchet mechanism (27) with a ratchet pawl (29) for rotary actuation of the adjusting ring (17), that the ratchet pawl (29) with its ratchet teeth (31) is in tooth engagement with an adjusting ring toothing (39), and that the ratchet pawl (29) is guided adjustably in the circumferential direction about an actuation path (b). Multi-plate brake / clutch according to claim 5, characterized in that a ratchet pawl adjustment takes place before the adjusting ring rotary actuation, that the ratchet pawl adjustment along the adjusting ring toothing (39) takes place when the multi-plate brake / clutch is loaded, in which the adjusting ring (15) is pressed rotationally fixed between the plate pack (1) and the actuator (3), and that the ratchet pawl adjustment takes place under the build-up of a spring return force. Multi-disc brake / clutch according to claim 6, characterized in that, following the ratchet pawl adjustment, the adjusting ring rotary actuation takes place with the multi-disc brake / clutch unloaded, in which the adjusting ring (17) is arranged to rotate freely between the lamellar pack (1) and the actuator (3), so that, for adjusting ring rotary actuation, the ratchet pawl (29) which is in tooth engagement with the adjusting ring toothing (39) is returned to its initial position by releasing the spring return force, and at the same time the adjusting ring (17) is rotated by the actuation path (b), whereby the ramp unit (21) expands axially by the adjustment path (n). Multi-plate brake / clutch according to claim 5, 6 or 7, characterized in that the ratchet pawl (29) is adjustable in the circumferential direction on the fixed disc (5) by means of guide elements (32, 38). Multi-plate brake / clutch according to claim 6, 7 or 8, characterized in that, for carrying out the ratchet pawl adjustment, the ratchet pawl (29) has a driver (33) by means of which the ratchet pawl (29) can be coupled to a movement stop (41) of the loose disc (7). Multi-disc brake / clutch according to claim 9, characterized in that, in a multi-disc brake / clutch set with a nominal clearance, i.e. without clearance interference, the rotary drive (13) rotates the loose disc (7) by a nominal rotation angle (αN) from the unloaded state to the loaded state, and that the ratchet pawl driver (33) remains decoupled from the loose disc movement stop (41) during a loose disc rotation beyond the nominal rotation angle (αN), or that, in a multi-disc brake with clearance interference, the rotary drive (13) rotates the loose disc (7) by a rotation angle from the unloaded state to the loaded state, which is greater than the nominal rotation angle (αN) by an additional angle (αZ), so that the ratchet pawl driver (33) remains decoupled from the loose disc movement stop (41) during the loose disc rotation until the The nominal rotation angle (αN) remains decoupled from the loose disc motion stop (41),However, after exceeding the nominal rotation angle (αN) via the additional rotation angle (αZ), the movement is coupled with the loose disc movement stop (41) in order to perform the ratchet pawl adjustment.

Images