Actuator arrangement for a friction plate clutch and differential arrangement with such an actuator arrangement

Abstract

The invention relates to an actuator arrangement comprising: a housing part (3) with a sleeve-shaped section (5) and a flange-shaped section (6); a ball ramp mechanism (4) with a support disc (7) and an actuating disc (8), wherein at least the support disc (7) is radially spaced from an outer surface (36) of the sleeve-shaped section (5); an actuating element (17) which is axially movable coaxially to the ball ramp mechanism (4) on the flange-shaped section (6) of the housing part (3), wherein an annular gap is formed between the outer surface (36) of the sleeve-shaped section (5) and the actuating element (17); and a spring element (23) which is arranged radially outside an actuating surface of the actuating element (17) axially between the housing part (3) and the actuating element (17) in order to exert a restoring force on the actuating element (17). The invention further relates to a differential arrangement with such an actuator arrangement.

Description

[0001] The invention relates to an actuator arrangement, in particular for actuating a controllable friction-disk clutch for locking a differential gear. The invention further relates to a differential arrangement with such an actuator arrangement.

[0002] Friction-disk clutches are used, for example, in lockable differentials, where actuation of the clutch creates a locking torque between the differential carrier and one of the sideshaft gears, and thus indirectly also between the sideshaft gears. In this way, a torque introduced into the differential carrier can be effectively generated at both sideshaft gears even if there is no counter-torque applied to one of the sideshaft gears. Differentials of this type can be used in motor vehicles as axle differentials between the drive wheels of a drive axle or as center differentials between two drive axles. They are also marketed by the applicant under the name "Electronic Controlled Torque Manager" (ETM®).

[0003] DE 10 2008 037 885 B4 shows various embodiments of clutch assemblies. In one embodiment, a ball ramp assembly is provided for actuating the clutch. An actuating disc of the ball ramp assembly acts on an axially movable pressure plate arranged in the outer disk carrier of the clutch.

[0004] DE 37 33 771 A1 discloses a four-wheel drive transfer case with an electromagnetic clutch unit. A magnetic coil acts on a multi-plate clutch via a friction disc. The friction disc is non-rotatably connected to the output shaft and is mounted on an extension of an adjacent planetary gear carrier.

[0005] From DE 32 12 495 A1 a differential gear for motor vehicles is known which can be locked by resiliently compressing a disk pack arranged on it.

[0006] From US 6 436 002 B1 a bevel gear differential mechanism is known which has a main and pilot clutch and a cam mechanism for increasing the engagement force of the pilot clutch, which is transmitted via a transmission element for actuating the main clutch.

[0007] From JP 2008-248 900 A, a differential with a differential limiting mechanism is known, the drive force transmission path from an actuator to a friction clutch is weight-reduced and the structure is simplified.

[0008] WO 2005 / 064206 A1 discloses a differential gear in which the differential carrier has a cup-shaped cage part in which the sideshaft gears and differential gears are housed, and a cup-shaped cover attached to it, in which the plates of the multi-plate clutch are housed. To actuate the multi-plate clutch, a ball-ramp mechanism is provided, which is arranged outside the differential carrier on a sleeve portion of the cover. The ball-ramp mechanism converts a rotary motion into an axial motion, which is transmitted to a pressure plate of the multi-plate clutch via several circumferentially distributed actuating elements extending axially through openings in the cover.

[0009] A differential gear with a controllable friction clutch is known from US Pat. No. 6,537,172 B1. The friction clutch is arranged axially adjacent to one of the output gears and can be actuated between an engaged state, in which relative rotation between the output gears and the differential carrier is retarded, and a disengaged state. The friction clutch is controllable by means of an electromagnetically actuated ball ramp actuator arranged adjacent to the opposite output gear. A plurality of circumferentially distributed elongated engagement parts are provided, which extend axially from the ball ramp actuator through the differential carrier to the friction clutch in order to transmit a ramping action of the ball ramp actuator axially to the friction clutch.

[0010] WO 2007 / 071314 A1 discloses a differential assembly with two friction clutches for variable torque distribution between two shafts in the drive train of a motor vehicle. The two friction clutches are each controlled by a ball ramp arrangement, which is actuated by a common actuator.

[0011] From EP 3 354 920 A1 a transmission arrangement with a friction-disk clutch is known, which can be controlled by means of a ball ramp arrangement.

[0012] DE 10 2014 113 937 B3 discloses a drive train with a longitudinal drive shaft that can be optionally engaged or disengaged by means of clutches. An upstream clutch comprises a friction plate pack and is actuated by means of a ramp arrangement.

[0013] The present invention is based on the object of proposing an actuator assembly, in particular for actuating a controllable friction-disk clutch, that has a simple and compact design. The invention further relates to a differential assembly with such an actuator assembly.

[0014] The object is achieved by a device according to claim 1 or a device according to claim 2. Further developments of the devices are the subject of the subclaims.

[0015] According to a first solution, an actuator arrangement is proposed, comprising: a housing part with a sleeve-shaped portion and a flange-shaped portion; a ball ramp arrangement with a support disc that is axially supported and an adjusting disc that is axially movable, wherein at least one of the support disc and the adjusting disc is rotatably driven by a drive source, and an introduced rotational movement is converted into an axial movement of the adjusting disc, and wherein at least the support disc is radially spaced from an outer surface of the sleeve portion of the housing part;an actuating element that is held axially movable coaxially to the ball ramp mechanism on the flange portion of the housing part, wherein an annular gap is formed between the outer surface of the sleeve portion and the annular actuating element, wherein the annular actuating element is axially supported at least indirectly against the adjusting disc on one side and has an actuating surface for actuating a friction disk clutch on the other side; and at least one spring element that is arranged radially outside the actuating surface of the actuating element axially between the housing part and the actuating element in order to exert a resilient restoring force on the annular actuating element that opposes the actuating force of the ball ramp arrangement; wherein the flange-shaped portion has a plurality of axial through-openings over the circumference;wherein the actuating element has a flange portion which has the actuating surface and has a radial overlap with the through openings, and a centering portion which extends from a radially outer end of the flange portion in the axial direction and engages around the housing part, and wherein the centering portion has an inner circumferential surface which is guided axially movably on an outer circumferential surface of the housing part;

[0016] According to a second solution, an actuator arrangement is proposed, comprising: a housing part with a sleeve-shaped portion and a flange-shaped portion; a ball ramp arrangement with a support disc that is axially supported and an adjusting disc that is axially movable, wherein at least one of the support disc and the adjusting disc is rotatably drivable by a drive source, and an initiated rotational movement is converted into an axial movement of the adjusting disc, and wherein at least the support disc is radially spaced from an outer surface of the sleeve portion of the housing part;an actuating element that is held axially movable coaxially to the ball ramp mechanism on the flange portion of the housing part, wherein an annular gap is formed between the outer surface of the sleeve portion and the annular actuating element, wherein the annular actuating element is axially supported at least indirectly against the adjusting disc on one side and has an actuating surface for actuating a friction-disk clutch on the other side; and at least one spring element that is arranged radially outside the actuating surface of the actuating element axially between the housing part and the actuating element in order to exert a resilient restoring force on the annular actuating element that opposes the actuating force of the ball ramp arrangement;wherein the sleeve-shaped portion of the housing part has a bearing seat on which a pivot bearing for the support ring is seated, wherein the housing part has a concave transition portion between the flange-shaped portion and the bearing seat of the sleeve-shaped portion, which extends axially from a side surface of the flange-shaped portion at least as far as the adjusting ring, and wherein the concave transition portion has a curvature whose radius is at least 0.5 times a smallest axial distance between the adjusting disc and the side wall of the housing part;

[0017] An actuator arrangement according to the invention is particularly suitable for controlling the transmittable torque of a friction-disk clutch in the drive train of a motor vehicle; it can also be referred to as an axial adjustment device. The clutch can be arranged inside the housing, and the actuator outside. To actuate the clutch, force-transmitting elements, such as bolts or pins, can be provided in the housing. These force-transmitting elements extend through through-openings in the housing to transmit the actuating force from the actuator to the clutch. The through-openings can extend through the flange-shaped section that forms a side wall of the housing. The actuator is reset via the spring element, although it is understood that one or more spring elements can be provided.The spring element is functionally located outside the force flow formed between the actuating element and the clutch, in particular radially outside the through-holes or the force transmission elements extending through them. This reduces the installation space between the housing and the actuating element by the space required by the spring.

[0018] The ball ramp arrangement is rotatably driven by a drive source, for example a controllable electric motor, and is designed to convert an initiated rotary movement into an axial movement. For this purpose, the adjusting disc and the support disc can each have a decreasing depth in the same circumferential direction when viewed from above onto their end faces. A ball is each received in pairs of opposing ball grooves, via which the adjusting disc and the support disc support each other axially. The adjusting disc is preferably mounted radially relative to the support disc exclusively via the balls. No further radial bearing is required for the adjusting disc, so that an annular gap can be formed between the outer surface of the sleeve section and the adjusting disc. This, in turn, has a positive effect on the design freedom for the sleeve section, which can be designed to optimize installation space and stress.

[0019] According to one embodiment, the actuating element has a flange portion that surrounds the pressure surface and radially overlaps the through-openings or the force transmission elements, and a centering portion that extends from a radially outer end of the flange portion in the axial direction and encompasses the housing part. This configuration also frees the actuating element from the sleeve portion of the housing part, which provides the aforementioned advantage with regard to the design of the housing part.

[0020] The centering section of the actuating element can have an inner circumferential surface that can be guided for axial movement on an outer circumferential surface of the housing part. Thus, the actuating element is radially centered relative to the housing part via the centering section extending in the axial direction and guided for axial movement. The centering section can be sleeve-shaped, i.e., with a circumferentially closed wall, or it can comprise several guide elements distributed over the circumference, extending in the axial direction and encompassing the housing.

[0021] According to one embodiment, a receiving space for the spring element is formed between the flange portion of the actuating element and an end wall of the housing part. The receiving space can have a greater axial extent than the smallest axial distance between the support surface of the actuating element and the end face of the housing. Thus, the axial length of the spring does not affect the arrangement of the actuating element, resulting in an overall axially compact design. The receiving space is preferably arranged radially outside the through-openings or the force transmission elements extending through them.

[0022] The spring element can have any design suitable for moving the actuating element back into its original direction, counter to the direction of action of the adjusting disc. For example, the spring can be annular, coaxial with the actuating element, and held radially on a circumferential surface of the actuating element. To prevent jamming, the spring is arranged with radial play relative to a circumferential surface of the parts defining the receiving space. The annular spring can be held radially outward relative to an inner circumferential surface of the centering section, or radially inward relative to an outer circumferential surface of a shoulder or sleeve extension of the housing or flange section. In particular, the spring element can be designed as a wave spring or disc spring, although other designs are also possible, such as multiple coil springs distributed around the circumference.

[0023] According to one embodiment, an axial bearing can be arranged between the adjusting disc and the actuating element. The axial bearing transmits axial forces between the adjusting disc and the actuating element, both in the closing and opening directions. At the same time, the axial bearing decouples relative rotational movements of the two elements from one another. The axial bearing can be supported radially on the outside of the actuating element, so that a radial gap is formed radially on the inside between the bearing and the housing. To accommodate the axial bearing, the actuating element can have an axially protruding collar in which the axial bearing is accommodated. Optionally, a washer can be provided between the actuating element and the axial bearing. The washer can be supported radially on the outside of the actuating element via the collar or collar. By designing the actuating element with an outer collar for centering on the housing orWith a collar for the axial bearing, the actuating ring is additionally reinforced and force-induced elastic deformation of the actuating ring is reduced. This leads to improved clutch response and a favorable contact pattern across the circumference during power transmission. This results in a particularly long bearing service life.

[0024] According to one embodiment, the support disc of the ball ramp mechanism is rotatably driven by a drive source, while the adjusting disc is rotationally fixed and axially movable. However, other designs are also possible, for example, the adjusting disc is rotationally driven and axially movable, while the support disc is rotationally fixed and axially supported. The support disc and adjusting disc have circumferentially variable-depth ball grooves on their mutually facing end surfaces. The ball ramp mechanism can be designed such that the centers of the balls received in the ball grooves radially overlap with the axial bearing and / or the support bearing for the support ring. This results in advantageous axial force transmission with low tilting moments.

[0025] According to one embodiment, the sleeve-shaped section of the housing part has a bearing seat on which a pivot bearing for the support ring is seated. The housing part has a concave transition section between the axial side surface and the bearing surface of the sleeve section, which extends axially from the side surface at least as far as the adjusting ring. The transition section has a free outer surface, preferably at least as far as the support disc, i.e., no components are mounted on the housing part between the end surface and the support ring or the support bearing. This section of the housing part, which is subject to large forces during operation, can thus be designed or constructed with stress optimization in mind, which also has a positive effect on the service life of the arrangement.

[0026] In further detail, the smallest outer diameter of the concave transition section can be smaller than the outer diameter of the bearing seat for the pivot bearing. Alternatively or additionally, the concave transition section can have a curvature whose radius is at least 0.5 times the smallest axial distance between the adjusting disc and the flange section of the housing part, in particular at least 0.6 times the smallest axial distance. Further alternatively or additionally, the smallest outer diameter of the concave transition section can be smaller than the radius of the external toothing of the coupling hub. One or more of these details can reduce the load on the housing part in this section.

[0027] The above-mentioned object is further achieved by a differential gear arrangement comprising: a differential gear with a differential carrier which can be driven to rotate about an axis of rotation, a plurality of differential gears which are rotatably mounted in the differential carrier about wheel axes running at an angle to the axis of rotation, and a first sideshaft gear and an opposite second sideshaft gear which are mounted in the differential carrier coaxially to the axis of rotation and are in toothed engagement with the differential gears; a friction multi-disk clutch with outer plates which are positively and axially movably connected to the differential carrier, and inner plates which are non-rotatably and axially movably connected to one of the first and second sideshaft gears, wherein the plate pack formed from the outer plates and inner plates can be axially loaded via a pressure plate;and an actuator arrangement designed according to one or more of the above-mentioned embodiments. The differential carrier comprises the housing part on which the ball ramp arrangement is arranged. Distributed around the circumference, several force transmission elements are provided, which extend axially through the through-openings of the housing part in order to transmit an axial movement of the adjusting disc to the pressure plate of the disk pack. The annular actuating element is arranged in particular between the adjusting disc and the force transmission elements, wherein the force transmission elements are in contact with a contact surface of the actuating element.

[0028] According to a first embodiment, the friction-disk clutch and the ball-ramp mechanism can be arranged on opposite sides of the differential carrier with respect to a plane spanned by the differential gear axes. The circumferentially distributed power transmission elements extend axially through the differential carrier or a casing section of the differential carrier and are axially guided therein. The differential carrier preferably comprises a first bearing seat and a second bearing seat in order to be rotatably mounted in a differential housing via suitable bearing elements. To introduce torque, a drive gear is rigidly connected to the differential carrier. Preferably, a smallest axial distance between the first and second bearing seats is smaller than an average tooth diameter of the drive gear.

[0029] According to a second embodiment, the friction-disk clutch and the ball-ramp mechanism can be arranged on the same side of the differential carrier with respect to the plane spanned by the differential gear axles. In this embodiment, the circumferentially distributed power transmission elements are shorter and extend through the side wall of the differential carrier, where they are axially guided.

[0030] Preferred embodiments are explained below with reference to the drawing figures. Herein: Fig. 1A shows an actuator arrangement according to the invention, for example for a controllable friction-disk clutch, in longitudinal section; Fig. 1B the actuator arrangement from Fig. 1A in perspective exploded view; Fig. 2A a differential arrangement with an actuator arrangement according to the Fig. 1A and Fig. 1B in longitudinal section in a first sectional plane in a first embodiment; Fig. 2B the differential arrangement from Fig. 2A in perspective view; Fig. 2C the differential arrangement from Fig. 2A in longitudinal section in a second cutting plane; Fig. 2D the differential arrangement Fig. 2A in a perspective exploded view; Fig. 3 a differential arrangement with an actuator arrangement according to the Fig. 1A and Fig. 1B in longitudinal section in a second embodiment; and Fig. 4 an actuator arrangement according to the invention in a modified embodiment in a semi-longitudinal section.

[0031] The Fig. 1A and Fig. 1B, which are described together below, show an actuator arrangement 2 according to the invention. This can be used, for example, to actuate a friction-disk clutch in the drive train of a motor vehicle.

[0032] The actuator assembly comprises a housing part 3 and a controllable ball ramp assembly 4, which is arranged coaxially with the housing part and can be driven by a schematically illustrated drive source 9. The housing part 3 can, for example, be part of a transmission or clutch housing and comprises, in particular, a sleeve-shaped section 5 and a flange-shaped section 6. The flange-shaped section 6 extends radially outward from the sleeve-shaped section 5 and forms a side wall of the housing.

[0033] The ball ramp arrangement 4 comprises a support disc 7, which is axially supported on the housing part 3, and an adjusting disc 8, which is axially movable relative to the support disc. In the present embodiment, the support disc 7 can be driven in rotation by the drive source 9, while the adjusting disc 8 is held in rotationally fixed position by anti-rotation means 55. For actuation, the support disc 7 has a toothed segment 10, into which a pinion 12 can engage for rotational drive. It is understood that other designs are also possible, for example, with a rotationally driven adjusting disc or other forms of torque transmission, such as by means of a rack or spindle drive.

[0034] The support disk 7 and the adjusting disk 8 each have, on their mutually facing end faces 13, 14, a plurality of ball grooves 15, 16 running in the circumferential direction, in each of which a ball is guided. The balls are located in a different sectional plane and are therefore not visible here. The ball grooves 15, 16 are designed such that a rotary movement introduced into the support disk 7 by the drive source is converted into an axial movement of the adjusting disk 8. For this purpose, the adjusting disk 8 and the support disk 7 can each have a decreasing depth in the same circumferential direction when viewed from above. However, a design is also possible in which only one of the two disks has ball grooves. In the present case, the adjusting disk 8 is radially mounted relative to the support disk 7 exclusively via the balls.Accordingly, no radial bearing is required relative to the housing part 3, so that in particular the sleeve-shaped section 5 can be designed advantageously with regard to the loads occurring during operation.

[0035] An annular actuating element 17 is provided for transmitting force between the ball ramp mechanism 4 and the component to be actuated. The actuating element 17 is held coaxially to the ball ramp mechanism 4 and axially movable on a guide section of the housing part 3. In further detail, the actuating element 17 has a flange section 18, which serves in particular for axial force transmission, and a centering section 19, which serves in particular for centering the actuating element 17 on the housing part 3.

[0036] The flange section 18, which can also be referred to as the actuating section, is axially supported on one side against the adjusting disc 8 and on the other side against the component to be actuated, for example a clutch. An axial movement of the adjusting disc 8 is thus transmitted to the component via the actuating element 17. It is understood that one or more additional elements can be interposed between the adjusting disc 8 and the actuating element 17 on the one hand, and between the actuating element and the component to be actuated on the other. For particularly good axial force transmission, the flange section 18 can have at least partial radial overlap with the ball grooves 15, 16 or with the balls of the ball ramp mechanism 4.

[0037] The centering section 19 extends from a radially outer end of the flange section 18 in the axial direction and encompasses an outer guide surface 20 of the housing part 3. The centering section 19 of the actuating element 17 can, in particular, have an inner circumferential surface 22 that is guided axially movably on an outer circumferential surface of the housing part 3. The outer circumferential surface thus forms the guide surface 20 for the actuating element 17 on the housing part. Overall, the actuating element 17 is radially centered and axially movably guided relative to the housing part 3 via the centering section extending in the axial direction. The centering section 19 is, in particular, sleeve-shaped, i.e., designed with a circumferentially closed wall, although other designs, for example, with several circumferentially distributed holding elements, are also possible.With the centering section 19, the actuating element 17 is advantageously centered radially outward and thus radially inwardly exposed relative to the housing part 3. The housing part 3 can thus be designed to optimize load capacity.

[0038] The actuator arrangement 2 further comprises a spring element 23, which is arranged axially between the housing part 3 and the actuating element 17 in order to exert a resilient restoring force on the actuating element 17, counteracting the actuating force of the ball ramp mechanism 4. The spring element 23 is designed here as a wave spring arranged coaxially with the actuating element, although it is understood that spring shapes other than restoring springs are possible. The spring element 23 is received or radially held in a receiving space 24 radially outside the flange section 18 and radially inside the centering section 19. Axially, the spring element 23 is arranged between the actuating element 17 and an end wall 25 of the housing part 3. The receiving space 24 has a greater axial extent than the smallest axial distance between the actuating surface 26 of the actuating element and the end wall 25 or end face of the housing.For this purpose, the actuating element 17 has a cranked section 27 radially outside the actuating section, which is axially offset from the actuating section in the direction of the adjusting disc 8. However, an alternative design is also possible in which the flange section 18 is continuously variable up to the centering section 19, but the housing part 3 has a recess or step radially outside. Preferably, the receiving space 24 or the spring element 23 is arranged radially outside and functionally parallel to the actuating surface 26 of the actuating element 17.

[0039] In the present embodiment, the force is transmitted between the adjusting disc 8 and the actuating element 17 via an optional axial bearing 28. The axial bearing 28 is arranged coaxially with the ball ramp mechanism 4; it transmits axial forces and decouples relative rotational movements. The axial bearing 28 is radially supported relative to the actuating element 17. For this purpose, the actuating element 17 has, on its side facing the adjusting disc 8, an axially projecting, in particular circumferential, collar 29, which forms a recess 32 for the axial bearing 28. An optional washer 30 is also provided between the actuating element 17 and the axial bearing 28. The washer 30 is also received in the recess 32 formed by the circumferential collar.

[0040] By designing the actuating element 17 with a centering section 19 or outer collar on the side facing the housing and / or with a collar section 29 or inner collar on the side facing the ramp mechanism 4, high rigidity is achieved and force-induced elastic deformation of the actuating element is reduced. This leads to improved responsiveness of a clutch actuated with this element and a favorable contact pattern across the circumference during power transmission.

[0041] The actuating element 17, the washer 30, the axial bearing 28, the support disk 7, and the adjusting disk 8 are radially spaced from an outer surface 36 of the sleeve-shaped portion 5 of the housing part. The support disk 7 of the ball ramp mechanism is axially supported against the sleeve-shaped portion 5 of the housing part 3. The housing part 3 has a bearing seat 33 on which a pivot bearing 34 sits, which is designed in particular as a combined axial / radial bearing. The bearing 34 is axially supported against the sleeve-shaped portion 5 by means of a retaining ring 54, although other designs are possible. The housing part 3 has a concave transition portion 35 between the flange-shaped portion 6 and the bearing seat 33, which extends axially from the side surface approximately to the support disk 7. The transition section 35 has a free outer surface 36, which means that no components are arranged or positioned between the side surface and the pivot bearing 34 on the housing part 3.A smallest outer diameter D35 of the concave transition section 35 can be smaller than the outer diameter D33 of the bearing seat 33 for the pivot bearing 34. Optionally, the concave transition section 35 can have a curvature whose radius R is at least 0.5 times a smallest axial distance L between the adjusting disc 8 and the flange section 6 of the housing part 3, in particular at least 0.6 times the smallest axial distance L. These configurations contribute to reducing the load on the housing part 3 in this section.

[0042] The actuator assembly 2 is particularly suitable for controlling a clutch for a motor vehicle drivetrain, whereby the clutch can be arranged inside and the actuator outside the housing part 3. The actuator is reset via the spring element 23, which is functionally arranged outside the force flow formed between the actuating element 17 and the clutch. This achieves a particularly compact design.

[0043] The Fig. 2A to 2D, which are described together below, show a differential arrangement 37 according to the invention with a friction disk clutch 41 which can be controlled by an actuator arrangement 2 according to the invention.

[0044] The differential assembly 37, which can be driven by a drive shaft (not shown), is designed to transmit or distribute an introduced rotary motion to two side shafts. The differential assembly 37 comprises a differential carrier 38, which is mounted in a stationary differential housing (not shown) for rotation about the rotation axis A by means of suitable bearings. The differential carrier 38 is constructed in two parts and comprises the housing part 3 and a cover part 39, which are connected to one another at a connecting flange 40. A ring gear (not shown), which can be driven by a drive shaft of the motor vehicle, can be attached to the connecting flange 40.

[0045] In the differential carrier 38, several differential gears 42 are rotatably mounted on bolts 43 arranged perpendicular to the rotational axis A, which rotate with the differential carrier 38. The differential gears 42 mesh with two sideshaft gears 44, 44', which in turn are connected in a rotationally fixed manner to an associated sideshaft. For this purpose, the sideshaft gears 44, 44' have shaft teeth 45, 45', into which the connecting pin of an associated sideshaft can be rotationally fixedly engaged. The differential gears 42 and the sideshaft gears 44, 44' together form a differential gear set for transmitting torque from the differential carrier 38 to the two sideshafts. To absorb spreading forces, low-friction thrust washers 46, 46', which can also be referred to as sliding washers, are provided between the sideshaft gears and the differential carrier 38.

[0046] To control the locking effect of the differential, the friction-disk clutch 41 is provided, which is arranged in the cover part 39, without being limited thereto. The clutch comprises outer plates 47, which are positively connected to the differential carrier 38 and axially movable, and inner plates 48, which are connected to one of the two sideshaft gears 44' in a rotationally fixed and axially movable manner. The plate pack formed from the outer plates and inner plates can be axially loaded via a pressure plate 49. The pressure force is controlled by means of the actuator arrangement 2, which is Fig. 1A and Fig. 1B, to whose description reference is made in this respect. The force is transmitted from the actuator to the pressure plate 49 via several force transmission elements 50 distributed over the circumference. The force transmission elements are designed in particular as bolts that extend axially through through openings 52 of the housing part 3. At one end, the bolts are axially supported against the actuating element 17, and at the other end against the pressure plate 49. An axial movement of the adjusting disc 8 is transmitted to the pressure plate 49 via the axial bearing, the actuating element, and the force transmission elements.

[0047] The pressure plate 49 acts on the disk pack, thereby reducing any compensating movement between the sideshaft gear 44' and the differential carrier 38, and thus also between the two sideshaft gears 44, 44'. The torque transmittable by the friction disk clutch 41 can be variably adjusted as required by appropriate control of the ball ramp mechanism 4. The clutch can be fully opened, allowing the two sideshaft gears to rotate freely relative to each other ("open" differential), or fully closed, completely blocking any compensating movement between the sideshaft gears ("closed" differential), or it can be operated in any intermediate state, partially blocking any compensating movement between the sideshaft gears.

[0048] In the Fig. In the embodiment shown in Figures 2A to 2D, the friction-disk clutch 41 and the ball-ramp mechanism 4 are arranged on opposite sides of the differential carrier 38 with respect to a plane E spanned by the differential gear axes B. The circumferentially distributed force transmission elements 50 extend axially through the casing section 51 of the differential carrier 38 and are guided axially movably therein.

[0049] At its opposite ends, the differential carrier 38 comprises a first bearing seat 53 and a second bearing seat 53'. Corresponding bearings can be mounted onto these, with which the differential carrier 38 is to be rotatably mounted in a differential housing (not shown). A minimum axial distance L53 between the two bearings or bearing seats can be smaller than an average tooth diameter of the drive flange. The actuating element 17 is arranged axially displaceably at the end of the casing section of the differential carrier 38. The spring element and the axial bearing are accommodated in the actuating element. Overall, the actuator arrangement 2 according to the invention in conjunction with the differential results in a particularly compact design.

[0050] Fig. 3 shows a differential arrangement 37 in a second embodiment with an actuator arrangement 2 according to the invention. This corresponds in terms of structure and function essentially to that of Fig. 2, to whose description reference is made. Identical or corresponding components are provided with the same reference numerals as in Fig. 2.

[0051] In contrast to the above embodiment, the friction-disk clutch 41 and the ball ramp mechanism 4 are arranged on the same side of the differential carrier 38 with respect to the plane E spanned by the differential gear axles B. In this embodiment, the circumferentially distributed force transmission elements 50 are shorter and extend axially through the side wall of the differential carrier 38. In the present embodiment, the actuating element 17 with its centering section 19 is also arranged axially displaceably on the outer surface of the differential carrier 38. In the present embodiment, the differential carrier 38 comprises a pot-shaped housing part in which the differential and the clutch are accommodated, as well as the housing part 3, which here is designed as a cover part.The housing part 5 has a connecting flange 56, which is inserted into a sleeve extension 57 of the cup-shaped housing part and is firmly connected thereto, in particular by means of a weld seam 58, but is not limited thereto. The actuator arrangement 2 corresponds in terms of structure and function to that shown in FIGS. Fig. 1 and Fig. 2, to whose description reference is made in this respect.

[0052] The Fig. Figure 4 shows an actuator arrangement 2 according to the invention in a modified embodiment. This largely corresponds to the embodiment according to the above Fig. 1A to 1B, to whose description reference is made. Identical or corresponding details are provided with the same reference numerals as in the above figures.

[0053] The only difference is that the annular spring element 23 in the embodiment according to Fig.4 is not held radially on an inner circumferential surface in the centering section 19 of the actuating element 17, but rather on an outer circumferential surface 11 of a shoulder 59 of the housing part 3. As in the above embodiments, the spring element 23 is arranged in the receiving space 24, in particular with radial play.

[0054] It is understood that the actuator arrangements 2 according to the invention are not limited to the applications described above, but can be used in any other devices in the drive train of a motor vehicle. For example, an actuator arrangement 2 according to the invention can also be used to actuate a hang-on clutch or a so-called twin-clutch arrangement, which does not require a differential. Reference symbol 2 Actuator arrangement 3 Housing part 4 ball ramp mechanism 5 sleeve-shaped section 6 flange-shaped section 7 Support disc 8 adjusting disc 9 Power source 10 gear segment 11 Circumferential surface 12 pinions 13 Front face (7) 14 Front face (8) 15 ball groove (7) 16 ball groove (8) 17 Actuating element 18 Flange section 19 Centering section 20 guide surface 21 outer peripheral surface 22 inner circumferential surface 23 Spring element 24 recording room 25 front wall 26 operating surface 27 Offset section 28 thrust bearings 29 collars 30 Washer 31 differential gears 32 recess 33 bearing seat 34 pivot bearings 35 Transition section 36 exterior area 37 Differential arrangement 38 Differential cage 39 Lid part 40 connecting flange 41 Friction-disk clutch 42 Differential gear 43 bolts 44, 44' sideshaft gear 45 Shaft splines 46 Thrust washer 47 outer slats 48 inner slats 49 printing plate 50 power transmission element 51 Sheath section 52 passage opening 53, 53' bearing seat 54 Retaining ring 55 Anti-rotation devices 56 Connecting flange 57 Sleeve attachment 58 Connection 59 shoulder A axis of rotation B Differential wheel axle E Level L distance R radius

Claims

[1] Actuator arrangement, in particular for actuating a friction-disk clutch (41) in the drive train of a motor vehicle, comprising: a housing part (3) with a sleeve-shaped section (5) and a flange-shaped section (6); a ball ramp mechanism (4) with a support disc (7) which is axially supported against the housing part (3) and an adjusting disc (8) which is axially movable, wherein at least the support disc (7) is radially spaced from an outer surface (36) of the sleeve-shaped section (5) of the housing part (3), an actuating element (17) which is held axially movable coaxially to the ball ramp mechanism (4) on the flange-shaped section (6) of the housing part (3), wherein an annular gap is formed between an outer surface (36) of the sleeve-shaped section (5) and the actuating element (17), wherein the actuating element (17) is axially supported at least indirectly against the adjusting disc (8) on one side and has an actuating surface (26) for acting on a friction disk clutch (41) on the other side, a spring element (23) arranged radially outside the actuating surface (26) of the actuating element (17) axially between the housing part (3) and the actuating element (17) in order to exert a resilient restoring force on the actuating element (17) opposite to the actuating force of the ball ramp mechanism (4), wherein the flange-shaped section (6) has a plurality of axial through-openings (52) over the circumference, wherein the actuating element (17) has a flange section (18) which has the actuating surface (26) and has a radial overlap with the through-openings (52), and a centering section (19) which extends from a radially outer end of the flange section (18) in the axial direction and engages around the housing part (3), wherein the centering section (19) has an inner circumferential surface (22) which is guided axially movably on an outer circumferential surface (21) of the housing part (3). [2] Actuator arrangement, in particular for actuating a friction-disk clutch (41) in the drive train of a motor vehicle, comprising: a housing part (3) with a sleeve-shaped section (5) and a flange-shaped section (6); a ball ramp mechanism (4) with a support disc (7) which is axially supported against the housing part (3), and an adjusting disc (8) which is axially movable, wherein at least one of the support disc (7) and the adjusting disc (8) is rotatably driven by a drive source, and an introduced rotary movement is converted into an axial movement of the adjusting disc (8), wherein at least the support disc (7) is radially spaced from an outer surface (36) of the sleeve-shaped section (5) of the housing part (3), an actuating element (17) which is held axially movable coaxially to the ball ramp mechanism (4) on the flange-shaped section (6) of the housing part (3), wherein an annular gap is formed between an outer surface (36) of the sleeve-shaped section (5) and the actuating element (17), wherein the actuating element (17) is axially supported at least indirectly against the adjusting disc (8) on one side and has an actuating surface (26) for acting on a friction disk clutch (41) on the other side, a spring element (23) arranged radially outside the actuating surface (26) of the actuating element (17) axially between the housing part (3) and the actuating element (17) in order to exert a resilient restoring force on the actuating element (17) opposite to the actuating force of the ball ramp mechanism (4), wherein the sleeve-shaped section (5) of the housing part (3) has a bearing seat (33) on which a pivot bearing (34) for the support disc (7) is seated, wherein the housing part (3) has a concave transition section (35) between the flange-shaped section (6) and the bearing seat (33) of the sleeve-shaped section (5), which extends axially from a side surface of the flange-shaped section (6) at least as far as the adjusting disc (8), and wherein the concave transition section (35) has a curvature whose radius (R) is at least 0.5 times a smallest axial distance (L) between the adjusting disc (8) and the side wall of the housing part (3). [3] Actuator arrangement according to claim 2, characterized by , that the flange-shaped section (6) has a plurality of axial through openings (52) over the circumference, wherein the actuating element (17) has a flange section (18) which has the actuating surface (26) and has a radial overlap with the through openings (52), and a centering section (19) which extends from a radially outer end of the flange section (18) in the axial direction and engages around the housing part (3), wherein the centering section (19) has an inner circumferential surface (22) which is guided axially movably on an outer circumferential surface (21) of the housing part (3). [4] Actuator arrangement according to one of claims 1 to 3, characterized by that a receiving space (24) for the spring element (23) is formed between the flange section (18) of the actuating element (17) and an end wall (25) of the housing part (3), wherein the receiving space (24) is arranged radially outside the through openings (52). [5] Actuator arrangement according to one of claims 1 to 4, characterized bythat the spring element (23) is annular and is held radially on a peripheral surface of the actuating element (17) or the housing (3). [6] Actuator arrangement according to one of claims 1 to 5, characterized by that the spring element (23) is designed in the form of a corrugated spring. [7] Actuator arrangement according to one of claims 1 to 6, characterized by , that the support disc (7) can be driven in rotation by a drive source, and the adjusting disc (8) is held in a rotationally fixed and axially movable manner, wherein the support disc (7) and the adjusting disc (8) each have on their mutually facing end faces (13, 14) a plurality of ball grooves (15, 16) extending in the circumferential direction, in each of which a ball is guided, wherein the ball grooves (15, 16) are designed such that a rotational movement introduced into the support disc (7) is converted into an axial movement of the adjusting disc (8), wherein an axial bearing (28) is arranged axially between the adjusting disc (8) and the actuating element (17), wherein the actuating element (17) has an axially projecting collar (29) against which the axial bearing (28) is radially supported. [8] Actuator arrangement according to claim 7, characterized by that the centers of the balls accommodated in the ball grooves (15, 16) have a radial overlap with the axial bearing (28). [9] Actuator arrangement according to claim 2, characterized by that a smallest outer diameter (D35) of the concave transition section (35) is smaller than the outer diameter (D33) of the bearing seat (33) for the pivot bearing (34). [10] Differential gear arrangement (37) comprising: a differential gear (31) with a differential carrier (38) which can be driven to rotate about an axis of rotation (A), a plurality of differential gears (42) which are rotatably mounted in the differential carrier (38) about wheel axes (B) running at an angle to the axis of rotation (A), and a first sideshaft gear (44) and an opposite second sideshaft gear (44') which are mounted in the differential carrier (38) coaxially to the axis of rotation (A) and are in toothed engagement with the differential gears (42), a friction-disk clutch (41) with outer disks (47) which are positively and axially movably connected to the differential carrier (38), and inner disks (48) which are rotationally fixed and axially movably connected to one of the first and second sideshaft gears (44, 44'), wherein the disk pack formed from the outer disks (47) and inner disks (48) can be axially loaded via a pressure plate (49), characterized by an axial adjustment device (2) according to one of claims 1 to 9, wherein the differential carrier (38) comprises the housing part (3) on which the axial adjustment device (2) is arranged, wherein a plurality of force transmission elements (50) are provided distributed over the circumference, which extend axially through the through openings (52) of the housing part (3) in order to transmit an axial movement of the adjusting disc (8) to the pressure plate (49) of the disk pack. [11] Differential gear arrangement (37) according to claim 10, characterized by that the annular actuating element (17) is arranged between the adjusting disc (8) and the force transmission elements (50), wherein the force transmission elements (50) are in contact with a contact surface of the actuating element (17). [12] Differential gear arrangement (37) according to claim 10 or 11, characterized bythat the friction-disk clutch (41) and the ball ramp mechanism (4) are arranged on opposite sides of the differential carrier (38) with respect to a plane (E) spanned by the differential wheel axes (B), wherein the circumferentially distributed force transmission elements (50) extend axially through the differential carrier (38) and are guided axially therein. [13] Differential gear arrangement (37) according to one of claims 10 to 12, characterized by , that the differential carrier (38) has a first bearing seat (53) and a second bearing seat (53') in order to be rotatably mounted in a stationary differential housing by means of bearing elements, wherein the differential carrier (38) has a connecting flange (40) to which a drive wheel can be firmly connected for introducing a torque, wherein a smallest axial distance (L53) between the first and second bearing seat (53, 53') is smaller than a mean diameter (D) of the connecting flange (40) or drive wheel. [14] Differential gear arrangement (37) according to one of claims 10 to 12, characterized by that the friction-disk clutch (41) and the ball ramp mechanism (4) are arranged on the same side of the differential carrier (38) with respect to a plane (E) spanned by the differential wheel axes (B), wherein the circumferentially distributed force transmission elements (50) extend axially through a side wall of the differential carrier (38) and are guided axially therein.

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