Ramp release device

Abstract

Ramp release device, comprising a position-fixed support disk (2), a release disk (3) which is rotatable and axially movable relative to the support disk (2) and has a coupled release bearing (4), a plurality of balls (6) provided between the support disk (2) and the release disk (3), which balls are guided in a ball guide (5) provided on the support disk (2) and the release disk (3) and which comprises a ramp structure (7) with a plurality of ramps (24, 25), and an axially position-fixed drive disk (8) which is coupled to the release disk (3) and is rotatable relative to the support disk (2) via a drive means (15), wherein upon rotation of the drive disk (8), the release disk (3) is carried along and the balls (6) run onto the ramps (24, 25) with axial displacement of the release disk (3).

Description

[0001] The invention relates to a ramp release device.

[0002] Such a ramp release device, as known, for example, from DE 10 2014 208 693 A1, serves, for example, to actuate a clutch device via which a drive means such as an internal combustion engine or an electric motor can be coupled to and decoupled from an output element. The ramp release device makes it possible to convert a rotational movement into an axial actuating movement via a ramp structure, via which axial actuating movement the clutch device is actuated. For example, such a ramp release device can be used to actuate a clutch device that is part of a hybrid module comprising an internal combustion engine and an electric motor, both of which operate on a common output element. The clutch device can be used to couple or decouple the internal combustion engine to or from the output element as needed, while the electric motor is permanently coupled to the output element.

[0003] The invention is based on the problem of providing an improved ramp release device.

[0004] To solve the problem, according to the invention, a ramp release device is provided, comprising a position-fixed support disc, a release disc which is rotatable and axially movable relative to the support disc and has a coupled release bearing, a plurality of balls provided between the support disc and the release disc, which balls are guided in a ball guide provided on the support disc and the release disc comprising a ramp structure with a plurality of ramps, and an axially position-fixed drive disc which is coupled to the release disc and is rotatable relative to the support disc via a drive means, wherein upon rotation of the drive disc, the release disc is carried along and the balls run onto the ramps with axial displacement of the release disc.

[0005] The ramp release device according to the invention has two disks that are rotatable relative to one another and axially movable relative to one another, namely a position-fixed support disk that is neither rotated nor axially movable and is, for example, fixed to a housing or is itself part of the housing. Secondly, a rotatable release disk that is axially movable relative to the support disk, to which a release bearing is coupled, which in turn is coupled, for example, to the clutch device, which rotates, wherein an axial movement of the release disk can be transmitted to the clutch device via the release bearing, but at the same time the clutch device is also rotatably mounted relative to the release disk. Furthermore, a ramp structure is provided, to which a plurality of balls are assigned, which are received or guided in a ball guide on the support disk and the release disk.A rotation of the release disc also causes a movement of the balls relative to the ramp structure, during which the balls run onto the ramps of the ramp structure, resulting in an axial displacement of the release disc and, with it, of the release bearing. To enable the rotation of the release disc, the invention provides a drive disc which is coupled to a drive means and which is rotatable but axially fixed. The drive disc is connected to the release disc, so that a rotation of the drive disc results in a rotation of the release disc. The connection between the two discs is such that the connection is maintained even during the axial displacement of the release disc relative to the fixed drive disc, i.e.that the connection is so flexible that it maintains the rotationally fixed coupling in every relative position, but at the same time also allows axial displacement.

[0006] During operation, therefore, only the drive disk is rotated by a specific angular increment via the drive means, for example an electric motor that is suitably mechanically coupled to the drive disk. This results in a rotation of the release disk, which is simultaneously axially displaced via the balls running onto the ramps, so that the release bearing, which is also axially displaced, can actuate the coupled clutch device. The drive disk therefore retains its axial position, i.e. it only needs to be mounted in a rotational manner. This allows a correspondingly simple design of the drive coupling to the drive means, for example via a gearing within which no disengagement is necessary, or via other simple drive connections, for example via a traction device or similar. The drive can therefore be designed as simply as possible.

[0007] According to the invention, the drive disc can be coupled to the release disc via one or more spring elements serving as drivers, wherein the drive disc is preferably preloaded against the support disc via the spring element(s). Forming the mechanical connection between the drive disc and release disc via the spring element(s) is advantageous in several respects. Firstly, these spring elements, for example simple leaf springs, can be used to create a simple, non-rotatable, yet axially elastic driver connection, which thus easily allows the torque introduced at the drive disc to be transmitted to the release disc, while at the same time enabling and reversing the axial displacement of the release disc relative to the drive disc.On the other hand, the spring element(s) can also be used to achieve an axially fixed arrangement of the drive pulley on the support pulley through the achievable preload, if necessary. This preload, which secures the drive pulley against the support pulley, is useful when this axial fixation cannot be achieved through other bearing means. If the spring elements are used to brace the drive pulley against the support pulley, the spring elements, for example, the leaf springs, are designed to always press the drive pulley against the support pulley at all operating points.

[0008] In principle, it is advisable for the drive pulley to be mounted against the support pulley via an axial bearing or a friction disc. This means that the axial bearing or friction disc provides the lowest possible friction between the drive pulley and the support pulley.

[0009] A leaf spring is expediently used as the spring element, with at least two leaf springs distributed around the circumference of the rotationally symmetrical arrangement of the two drive and release discs, designed as annular discs. However, an arrangement of three or more leaf springs is also conceivable.

[0010] The axial displacement of the release disc occurs, as described, via the ramp structure and the associated balls. Preferably, at least three balls and at least one associated ramp are arranged, preferably equidistantly, around the circumference. These at least three balls support the two discs relative to each other at three support positions, preferably equidistantly distributed around the circumference, ensuring symmetrical support and thus symmetrical axial movement. Of course, more than three balls and a corresponding number of ramps can also be provided distributed around the circumference.

[0011] It is also expedient to provide ramps on both the release disc and the support disc, with each ball being assigned a ramp on the release disc and the support disc. This effectively creates a double-sided ramp arrangement, so that when the discs rotate relative to each other, each ball simultaneously runs onto two ramps. This results in a virtually double axial travel compared to a design with only one ramp. This, in turn, allows the axial travel to be achieved with a correspondingly small rotation of the drive disc and thus also of the release disc.

[0012] To limit the rotational movement of the release disc relative to the support disc, circumferential stops are advantageously provided in the ramp structure. Consequently, the balls can only run up to the stops on the ramp(s), which limit the run-up movement and thus the maximum rotation angle, as well as the maximum axial displacement. The stops can, for example, be designed as corresponding end stops at the end of the ramps; a ramp flank pointing in the circumferential direction can also serve as the end stop.

[0013] The ramps themselves can rise straight, progressively, degressively or in steps, depending on how the desired force-displacement curve is to be set.

[0014] The balls themselves can run freely, but they can also be held in a cage that positions them relative to each other, so that their relative position does not change due to the cage guide. The cage can also be used to limit the travel at a stop.

[0015] As already described, different drive options are conceivable for the rotary drive of the drive pulley. The drive pulley can have a toothing with which a toothed drive element of the drive means meshes. The toothing or design of the drive element can be of a different nature. Possible options are spur gear toothing, crown gear toothing, bevel gear toothing or worm gear toothing with a corresponding positioning of the toothing on the drive pulley and a corresponding design of the drive element, which is driven via the drive means, for example an electric motor. Alternatively, the drive pulley can also be connected to a traction device of the drive means. Such a traction device could, for example, be a cable or a lever, which is moved via the drive means, for example an electric motor.

[0016] In addition to the ramp release device itself, the invention further relates to a coupling device for a hybrid drive device comprising an internal combustion engine and an electric machine for detachably connecting the internal combustion engine to an output element which is coupled to the electric machine, comprising an input element to be coupled to the internal combustion engine, a damper device connected downstream of this input element, a clutch device connected to the damper device and to which the output element is coupled, a gear to be coupled to the electric machine, connected to the output element and carrying a disk carrier of the clutch device, as well as a ramp release device of the type described above, the release bearing of which is coupled to the disk carrier of the clutch device, which is actuated upon an axial movement of the release bearing as a result of an axial displacement of the release disc.The coupling device is therefore part of a hybrid drive system or is integrated into it and serves to couple or decouple the internal combustion engine with the output element as needed. The output element is permanently coupled to the electric motor and can therefore always be driven by this electric motor when switched to motor mode. If necessary, the internal combustion engine can be coupled and provide additional torque, just as the drive is to be provided solely by the internal combustion engine when the rotor of the electric motor is merely driven. The internal combustion engine can also be decoupled if necessary, namely when the electric motor is switched to generator mode and the rotor is driven by the output element coupled to it for the purpose of recuperation.

[0017] The invention is explained below using exemplary embodiments with reference to the drawings. The drawings are schematic representations and show: Fig. 1 a schematic diagram of a ramp release device of a first embodiment, Fig. 2 a schematic diagram of a ramp release device of a second embodiment, Fig. 3-7 different designs of a mechanical drive connection of a drive means with the drive pulley of the ramp release device, Fig. 8 a schematic diagram of a ramp release device in the retracted position, Fig. 9 a partial view along the line IX-IX Fig. 8, Fig. 10 a partial view along the line XX from Fig. 8, Fig. 11 a schematic diagram of the ramp release device from Fig. 8 in the extended position, Fig. 12 a partial view along the line XII-XII from Fig. 11, Fig. 13 a partial view along the line XIII-XIII from Fig. 11, Fig. 14-16 different partial views of the ramp structure with different stop variants, and Fig. 17 a schematic diagram of a coupling device comprising a ramp release device according to the invention.

[0018] Fig. 1 shows a schematic diagram of a ramp release device 1 according to the invention, comprising a fixed support disk 2, which is arranged in a fixed position, for example, on a housing or is part of a housing. Also provided is a release disk 3 which is rotatable and axially movable relative to the support disk 2 and on which a release bearing 4 is arranged, which in the assembled position is coupled to an element to be actuated, for example a clutch device. Furthermore, a plurality of balls 6 guided in a ball guide 5 are provided, wherein the ball guide 5 has a ramp structure 7 comprising a plurality of ramps onto which the balls 6 can run upon rotation of the release disk 3 relative to the support disk 7, which results in an axial displacement of the release disk 3 relative to the fixed support disk 2. The support disk 2 and the release disk 8 are designed as metal annular disks.

[0019] Furthermore, a drive disk 8 is provided, which in the example shown is supported on the support disk 2 via an axial bearing 9. The drive disk 8, which in the assembled position is coupled to a suitable drive means, is rotatably mounted and thus rotatable relative to the support disk 2. It is further connected to the release disk 3 via spring elements in the form of leaf springs 11 serving as drivers 10, wherein the ends of the leaf springs 11 are connected via corresponding rivet connections 12, 13 to the drive disk 8 on the one hand and to the release disk 3 on the other. The drive disk 8 is also designed as a metal annular disk.

[0020] To carry out an adjusting movement, the drive disk 8 is rotated about the central axis of rotation 14 of the ramp release device 1 via the drive means (not shown in detail). The release disk 3 is driven in the same way via the drivers 10 or leaf springs 11, i.e. it is also rotated relative to the support disk 2. The balls 6 run onto the ramps of the ramp structure 7, so that the rotation of the release disk 3 also leads to an axial displacement of the release disk 3 and with it the release bearing 4. Due to the design of the drivers 10 as leaf springs 11, this mechanical connection ensures, on the one hand, that the release disk 3 is driven during an active rotation of the drive disk 8, and on the other hand, the leaf springs 11 also allow an elastic connection that enables the axial displacement of the release disk 3, which also occurs relative to the axially fixed drive disk 8.The design is preferably such that the leaf springs 11 preload the drive disk 8 axially against the support disk 2 at every operating point via the axial bearing 9. Distributed around the circumference, at least two leaf springs 11 are provided, optionally also more than two leaf springs 11, preferably equidistantly spaced. Furthermore, at least three balls 6 with correspondingly assigned ramps are provided; optionally, more than three balls and then a correspondingly higher number of ramps can also be provided.

[0021] Fig. Figure 2 shows a second embodiment of a ramp release device 1 according to the invention, wherein the same reference numerals are used for the same components. The structure is almost identical to the design according to Fig. 1. A support disc 2 and a release disc 3 are provided for the associated release bearing 4 and a ball guide 5 together with balls 6 and a ramp structure 7. A drive disc 8 is also provided, which is connected to the release disc 3 via corresponding drivers 10 in the form of the leaf springs 11 via suitable rivet connections 12, 13. Unlike the design according to Fig. 1, the angled or bent drive disc 8 is mounted via the axial bearing 9 on the side of the support disc 2, which is bent in the principle example here, facing away from the release disc 3. Here, too, the design of the leaf springs 11 is expediently such that the leaf springs 11 again preload the drive disc 8 axially against the support disc 2 at every operating point.

[0022] Fig. 3 shows a first variant of the ramp release device 1, such as from Fig. 2 is known, wherein here a spur gear 16 is provided as a drive connection between the drive disk 8 and the drive means 15, which is provided on the support disk 8 and a drive element 17 of the drive means 15, which further has, for example, an electric motor 18.

[0023] When designing according to Fig. 4, the mechanical coupling between the support disk 8 and the drive means 15 is realized via a bevel gear or crown gear toothing 19, for which purpose corresponding toothings are provided on the drive disk 8 and the drive element 17.

[0024] When designing according to Fig. 5, the mechanical coupling between the drive disk 8 and the drive means 15 is realized via a worm gear toothing 20, for which purpose a worm gear toothing is provided on the outer circumference of the drive disk 8 and a worm gear toothing is also provided on the drive element 17 designed as a worm gear.

[0025] When designing according to Fig. 6, the drive means 15 comprises a traction means 21, here in the form of a rope 22, which can be wound onto and unwound from a winding shaft via an electric motor 18.

[0026] When designing according to Fig. 7, a traction means 21 is also provided, but here in the form of a lever 23 which is coupled to the electric motor 18 and can be pulled or pushed.

[0027] All in the Fig. The mechanical connections shown in Figures 3 - 7 allow the drive disk 8 to be rotated about the axis of rotation 14 and thereby realize the corresponding rotation of the release disk 3.

[0028] The Fig. 8 - 13 show the ramp release device 1 as well as enlarged views of the mechanical connection of the drive disc 8 and the release disc 3 as well as the ramp structure 7 in the non-actuated, retracted position ( Fig. 8, Fig. 9, Fig. 10) and corresponding views in the actuated, extended position ( Fig. 11, Fig. 12, Fig. 13.

[0029] in the in the Fig. 8, Fig. 9, Fig. In the position shown in Figure 10, the drive disc 8 is not actuated. The release disc 3 is located in close proximity to the support disc 2, the leaf springs 11 are not deformed, as the Fig. 8 and Fig. 9. The balls 6 are accommodated between two ramps 24, 25 and rest against their front flanks 26, 27, as Fig. 10 shows. The ramps 24 are provided on the support disc 2, while the ramps 25 are provided on the release disc 3. If, starting from this non-actuated position, the drive disc 8 is rotated, as indicated by the arrow P in Fig. 9, the release disc 3 is also rotated via the connection via the leaf springs 11, as described, which causes the ramp structure to be twisted. This means that the balls 6 run onto the ramps 24, 25, resulting in an axial displacement of the release disc relative to the fixed support disc 2, but also relative to the likewise fixed drive disc 8. Fig. 11, Fig. 12 show the axial displacement, the distance between the release disc 3 and the drive disc 8 or the support disc 3 is clearly increased, compared to the Fig. 8 and Fig. 9. The leaf springs 11 are deformed accordingly, whereby due to the deformability of the leaf springs 11, this axial displacement is possible without any problems. At the same time, as Fig. 13, the balls 6 on both ramps fell 20, 25, which is the cause of the axial stroke. The rotational movement is conveniently limited by stops. The Fig. 8 and Fig. The release bearing 4 shown in Figure 11 is also axially displaced together with the release disc 3. Since the clutch device is coupled to the release bearing 4, it is also actuated axially. Consequently, an axial force is introduced into the clutch device, which, depending on the design of the clutch device, leads to the opening or closing of the clutch device.

[0030] The force-displacement ratio can be adjusted depending on the design of the gradient of the ramps 24, 25—i.e., whether the ramp surface is straight, progressive, degressive, or stepped. For example, the steeper the ramps 24, 25 are, the greater the displacement per degree by which the drive disk 8 is rotated. Furthermore, since the ramps 24, 25 are provided on both sides and the balls 6 run on two ramps, twice the displacement in the axial direction can be covered compared to the design in which a ramp structure is provided on only one side.

[0031] If the drive disc 8 is rotated back again, which is effected via the drive means 15 or the electric motor 18, the arrangement resets itself, i.e., the drive disc 8 rotates the release disc 3 back again, the balls 6 run down the ramps 24, 25 again, and the release disc 3 returns to its initial position adjacent to the drive disc 8. The clutch device is no longer actuated.

[0032] The Fig. 14 - 16 show different designs of a stop limiter. In Fig. 14, the backward movement into the retracted basic position is limited by the balls 6 striking the end faces 26, 27 of the ramps 24, 25. In the opposite direction, the end stop can be achieved, for example, by a rotation limiter 28, which limits the rotation of the release disc 3 relative to the support disc 2, as shown in Fig. 15. Alternatively, corresponding stops 29, 30 can be provided at the ends of the ramps 24, 25, against which the balls 6 run, as in Fig. 16 shown.

[0033] Fig.17 finally shows a schematic diagram of a coupling device 31 comprising a ramp release device 1 according to the invention. The coupling device couples, for example, an input element such as a crankshaft stub 32 to an output element 33, which is connected, for example, to a transmission shaft (not shown). A torque generated by an internal combustion engine connected to the crankshaft stub 32 is introduced via the crankshaft stub 32. This torque is initially applied to a damper device 34, via which corresponding rotational irregularities of the crankshaft stub 32 resulting from the operation of the internal combustion engine are damped. Downstream of the damper device 34 is a clutch device 35, which in turn is coupled to a preferably helical gear 36, which is coupled to an axially parallel electric motor (not shown in detail). The gear 36 serves as a clutch carrier.The clutch device 35 can be actuated axially via the ramp release device 1, to which the clutch device is connected via the release bearing 4, so that a disk pack 37 of the clutch device can be opened and closed. In the closed state, the internal combustion engine is connected in a rotationally fixed connection to the output element 33 via the crankshaft stub 32, i.e., an introduced torque is transmitted to the output element 33 via the damper device 34 and the clutch device 35. At the same time, the electric motor is also permanently engaged with the gear 36 and therefore permanently connected to the output element 33. Consequently, a torque can be transmitted to the output element 33 via both drive units.

[0034] However, if the internal combustion engine is to be decoupled, for example when the electric motor is switched to generator mode to recuperate energy, the ramp release device 1 is actuated and, as described above, the release disc 3 and with it the release bearing 4 are axially displaced, so that a disk carrier 38 of the clutch device 35, which engages with fingers through openings provided on the gear 36 and is thereby carried along by the gear 36, is axially displaced, which leads to the disk pack 37 being opened, i.e., released, and the rotationally fixed connection being released. Therefore, in this steep position, a torque can no longer be transmitted from the internal combustion engine to the output element 33, or the internal combustion engine 33 is not driven via the output element 33.The torque of the output element 33 is transmitted exclusively to the gear 36, which drives the rotor of the electric motor connected as a generator, generating and recuperating energy there. If the internal combustion engine is to be reconnected, the ramp release device 1 is reset, so that the clutch device 35 closes again and the rotationally fixed connection is reestablished. List of reference symbols 1 ramp release device 2 support discs 3 release disc 4 release bearings 5 Ball bearing 6 balls 7 Ramp structure 8 release disc 9 thrust bearings 10 carriers 11 Leaf spring 12 riveted joint 13 Riveted connection 14 axis of rotation 15 Propulsion means 16 spur gearing 17 Drive element 18 electric motor 19 Bevel gear or conrad gearing 20 Worm gear teeth 21 traction devices 22 rope 23 levers 24 Ramp 25 Ramp 26 Front flank 27 Front flank 28 Rotation limit 29 stop 30 stops 31 Coupling device 32 Crankshaft stub 33 Output element 34 Damper device 35 Coupling device 36 gear 37 disc pack 38 slat carriers P Arrow QUOTES CONTAINED IN THE DESCRIPTION

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

[0000] DE 10 2014 208 693 A1

[0002]

Claims

[1] Ramp release device comprising a position-fixed support disk (2), a release disk (3) rotatable and axially movable relative to the support disk (2) with a coupled release bearing (4), several balls (6) provided between the support disk (2) and the release disk (3), which are guided in a ball guide (5) provided on the support disk (2) and the release disk (3) comprising a ramp structure (7) with several ramps (24, 25), and an axially position-fixed drive disk (8) coupled to the release disk (3) and rotatable relative to the support disk (2) via a drive means (15), wherein when the drive disk (8) rotates the release disk (3) and the balls (6) run onto the ramps (24, 25) with axial displacement of the release disk (3). [2] Ramp release device according to claim 1, characterized bythat the drive disc (8) is coupled to the release disc (3) via one or more spring elements serving as drivers (10), wherein preferably the drive disc (8) is preloaded against the support disc (2) via the spring element(s). [3] Ramp release device according to claim 2, characterized by , that the drive disc (8) is supported against the support disc (2) via an axial bearing (9) or a friction disc. [4] Ramp release device according to claim 2 or 3, characterized by , that the spring element(s) are leaf springs (11). [5] Ramp release device according to one of the preceding claims, characterized by , that at least three spheres (6) and at least one associated ramp (24, 25) are arranged, preferably equidistantly, around the circumference. [6] Ramp release device according to one of the preceding claims, characterized by, that ramps (24, 25) are provided on both the release disc (3) and the support disc (2), wherein each ball (6) is assigned a ramp (24, 25) of the release disc (3) and the support disc (2). [7] Ramp release device according to one of the preceding claims, characterized by , that the ramp structure (7) has circumferentially acting stops (29, 30) which limit the rotational movement of the release disc (3) relative to the support disc (2). [8] Ramp release device according to one of the preceding claims, characterized by , that the balls (6) are held in a cage. [9] Ramp release device according to one of the preceding claims, characterized by , that the drive disc (8) has a toothing with which a toothed drive element (17) of the drive means (15) meshes, or that the drive disc (8) is connected to a pull element (21) of the drive means (15). [10] Coupling device for a hybrid drive system comprising an internal combustion engine and an electric machine for separably connecting the internal combustion engine to an output element (33) coupled to the electric machine, comprising an input element (32) to be coupled to the internal combustion engine, a damper device (34) downstream of the input element, a clutch device (35) connected to the damper device (34) with which the output element (33) is coupled, a gear to be coupled to the electric machine, connected to the output element and supporting a plate carrier of the clutch device, and a ramp release device (1) according to one of the preceding claims, the release bearing (4) of which is coupled to the plate carrier of the clutch device (35), which is actuated by an axial movement of the release bearing (4) as a result of an axial displacement of the release disc (3).

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