Power transmission device

Abstract

Power transmission device (1) with at least one input (E), one output (A), a switchable friction-fit coupling device (6) arranged in the power flow between these, and a device (7) downstream of this for damping vibrations, comprising at least two damper parts (10, 11) which are rotatable relative to each other in the circumferential direction to a relatively limited extent and are coupled to each other via means (8, 9) for torque transmission and / or damping coupling, and with means for discharging the axial forces caused by the actuation of the switchable coupling device (6) from the device (7) for damping vibrations, characterized in that the means for discharging comprise at least one axial bearing (3) between the damper part (10) non-rotatably connected to the switchable coupling device (6) and the input (E) of the power transmission device (1) or an element non-rotatably connected to it.wherein the axial bearing (3) is designed as a rolling bearing or as a sliding bearing, wherein the outlet (A) or an element non-rotatably connected to the outlet (A) comprises at least two sub-areas (19, 20) each forming an outer circumference, wherein the first sub-area (19) corresponds to the arrangement area of ​​the axial bearing (3) and the second sub-area (20) forms an axial contact surface (22) for the damper part (10) on its end face (13.2) facing away from the axial bearing (3), wherein the first sub-area (19) and the second sub-area (20) are arranged directly adjacent to each other in the axial direction.

Description

[0001] The present invention relates to a power transmission device according to the preamble of patent claim 1. In particular, the invention relates to a power transmission device with at least one input, one output, a switchable frictional coupling device arranged in the power flow between these and a device for damping vibrations arranged downstream of this, comprising at least two damper parts which are rotatable relative to one another in the circumferential direction to a limited extent and are coupled to one another via means for torque transmission and / or damping coupling and with means for discharging the axial forces caused by the actuation of the switchable coupling device from the device for damping vibrations.

[0002] Power transmission devices for use in drive trains, comprising at least one input and one output and a switchable clutch device arranged therebetween, with a first and a second clutch part that can be brought into operative connection with one another at least indirectly by means of an actuating device, are known in a variety of designs from the prior art. The design of switchable clutch devices in the form of frictional clutches depends on the torque to be transmitted and the available installation space, usually as a single-disk clutch or a multi-disk clutch, in particular a multi-plate clutch.For this purpose, the individual clutch parts comprise at least one, preferably a plurality of friction surface-bearing and / or friction surface-forming elements, which are frictionally connected to one another via a corresponding actuating force, resulting in an axial clutch force, forming friction pairs. Such power transmission devices are integrated into drivetrains between a drive, in the form of an internal combustion engine when used in vehicles, and other transmission elements, in particular a transmission. To compensate for the rotational irregularities introduced into the drivetrain via the drive engine, a vibration damping device with a predefined damping capacity is arranged downstream of the switchable clutch device in the power flow.This comprises at least two damper parts that are circumferentially rotatable relative to one another to a limited extent and coupled to one another via means for torque transmission and damping coupling, wherein the second clutch part of the switchable clutch device is non-rotatably connected to a first damper part that forms the damper input. When the switchable clutch device is actuated, axial forces are introduced into the vibration damping device via the connection to the vibration damping device. These axial forces are supported within the device, generating uncontrollable frictional moments and / or leading to a relative movement of damper parts. Both of these cause a deterioration in the isolating effect of the vibration damping device and thus a reduction in the actually available damping capacity.

[0003] One embodiment of a power transmission device is previously known, for example, from US Pat. No. 4,693,348. This describes a two-channel design with a switchable clutch device of single-disk construction, wherein the function of the clutch output and thus of the second clutch part is formed by the actuating device in the form of a piston element actuated by pressure medium, which is rotationally fixedly coupled to the damper input in the region of its outer circumference. The piston element is guided so as to be displaceable in the axial direction on an element that is rotationally fixedly coupled to the output of the power transmission device. The guidance takes place without a rotationally fixed connection. Through the coupling between the second clutch part, which forms the clutch output, and the damper input, the forces acting in the axial direction during clutch actuation are also introduced into the vibration damping device and supported by it.

[0004] From the publication DE 10 2007 055 145 A1, a design of a power transmission device is previously known in which the outer disk carrier of the switchable clutch device, as a component of the second output-side clutch part, is rotationally fixedly coupled to the damper input in the power flow between the input and output of the power transmission device. In this design, the axial clutch forces are essentially supported on an element that functions as an end disk and is rotationally fixedly coupled to the input of the power transmission device and forms a guide element for the cooling medium. This design is very complex.Furthermore, however, axial forces due to the hydrodynamic components can be introduced into the vibration damping device. Increased frictional forces due to axial displacement of damper components, which can also negatively impact the damping behavior, cannot be ruled out here either. In this embodiment, a bearing arrangement comprising at least one axial bearing is provided between the input or the element in the form of a piston hub that is non-rotatably coupled thereto and the output or an element that is non-rotatably coupled thereto and the damper output, in particular a damper hub.

[0005] An alternative design for supporting and transmitting axial forces resulting from clutch actuation toward the input of the power transmission device or toward the drive side is characterized by the damper component acting as the damper input in this direction being axially supported toward the engine by additional components, in particular a retaining ring. The retaining ring is arranged in a groove, preferably in the damper hub. The disadvantage of the groove, in addition to the additional manufacturing effort, is the notch effect.

[0006] As further prior art, reference is made to DE 10 2009 042 078 A1 and US 4 143 561 A, which disclose a power transmission device according to the preamble of claim 1.

[0007] The invention is therefore based on the object of further developing a power transmission device of the type mentioned above, in particular a design and arrangement of a device for damping vibrations within a power transmission device such that the coupling forces acting in the axial direction and toward the drive engine by actuating the switchable clutch device can be introduced into the respective connecting elements with low friction. This is intended to significantly improve the insulating effect of the vibration damping device and eliminate the need for complex additional components and their installation. The solution according to the invention is intended to be characterized by low design and manufacturing complexity.

[0008] The inventive solution is characterized by the features of claim 1. Advantageous embodiments are described in the subclaims.

[0009] A power transmission device according to the invention with at least one input, one output, a switchable frictional coupling device arranged in the power flow between these and a device for damping vibrations arranged downstream of this, comprising at least two damper parts which are rotatable relative to one another in the circumferential direction to a limited extent and are coupled to one another via means for torque transmission and / or damping coupling and with means for discharging the axial forces caused by the actuation of the switchable coupling device from the device for damping vibrations, is characterized in that the means for discharging comprise at least one axial bearing between the damper part which is connected in a rotationally fixed manner to the switchable coupling device and the input of the power transmission device or an element which is connected in a rotationally fixed manner to this.

[0010] The inventive solution enables the axial forces caused by clutch actuation to be easily diverted from the vibration damping device, in particular directly from the damper input to another component, thus preventing the axial forces from being supported within the vibration damping device. This prevents displacement of the individual damper components relative to one another and undesirably high additional frictional forces, which occur when axial forces are supported within the vibration damping device and lead to a reduction in damper capacity. The inventive solution makes it possible to introduce and compensate for the axial forces with low friction in elements that are non-rotatably connected to the input. Complex additional components can be eliminated.

[0011] The axial bearing can be a separate axial bearing designed specifically for this function, or, in a particularly advantageous embodiment, the axial bearing's function for dissipating the axial forces caused by the actuation of the switchable clutch device is at least partially taken over by an axial bearing arranged between the input or an element connected to it in a rotationally fixed manner and the output or an element connected to it in a rotationally fixed manner. This allows the axial support between the input and output to be ensured with a single component, while simultaneously dissipating the axial forces caused by clutch actuation.

[0012] The damper part, which is connected in a rotationally fixed manner to the switchable clutch device, is preferably arranged and designed such that it extends radially into the region of the radial extent of an axial bearing surface of the axial bearing, at least indirectly, preferably directly, contacting at least a partial region of this axial bearing surface. Preferably, the entire available axial bearing surface is used as a contact surface for the device for damping vibrations, in particular the damper input. Since the contact area with the axial bearing is located radially near the connection area between the damper part and the switchable clutch device, the axial forces can be diverted via the axial bearing via the shortest possible route from the damper part acting as the damper input. The effort required for such a design of the damper part is low and can be implemented in the axial direction without requiring additional installation space.

[0013] Structurally, the output or an element connected to the output in a rotationally fixed manner has at least two sub-regions, each forming an outer circumference, wherein the first sub-region corresponds to the arrangement region of the axial bearing and the second sub-region forms an axial contact surface for the damper part on its end face facing away from the axial bearing. According to the invention, both sub-regions are arranged directly adjacent to one another in the axial direction. The axial contact surface formed on the second sub-region corresponds in its extent in a particularly advantageous manner to the extension of the axial bearing surface in the radial direction. This ensures that the axial forces acting on the damper part are supported equally, regardless of their direction.

[0014] The input of the power transmission device is usually formed by a housing enclosing the switchable clutch device. In this case, support is preferably provided by a component coupled to it in a rotationally fixed manner, in particular a hub, which also performs other functions, in particular for guiding, centering, and supporting an actuating device for actuating the switchable clutch device.

[0015] In order to enlarge the centering surface of the damper part, the latter has an annular projection in the area of ​​its inner circumference directed in the axial direction away from the axial bearing, which has the axial contact surface for contact with the contact surface on the second part area.

[0016] In a further embodiment with only partial utilization of the axial bearing surface, a further third partial area forming an outer circumference is provided between the first and the second partial area of ​​the output or the element connected thereto in a rotationally fixed manner, which forms a contact surface for the axial bearing surface not stressed by the damper part and in whose axial extension area the damper part is arranged.

[0017] According to the invention, the axial bearing is a rolling bearing, preferably in the form of a needle bearing, or a plain bearing.

[0018] The input of the power transmission device is preferably formed by a housing part enclosing the switchable clutch device, to which a hub for centering and / or guiding the actuating device of the switchable clutch device is connected in a rotationally fixed manner. The axial bearing is then arranged between the damper part and the hub.

[0019] The output or the element connected to the output in a rotationally fixed manner is preferably formed by a damper hub connected in a rotationally fixed manner to the damper part forming the damper output.

[0020] The individual damper parts, in particular the damper part connected to the switchable clutch device, can comprise one or more disc-shaped elements. If the damper part formed with the switchable clutch device is designed in at least two parts, it preferably comprises at least two drive plates that are connected to one another in a rotationally fixed manner and arranged at a distance from one another in the axial direction. In this case, the axial bearing is arranged between the drive plate connected to the switchable clutch device and the input or the element connected to it in a rotationally fixed manner.

[0021] In an alternative embodiment, the damper part connected to the switchable clutch device is designed as a flange.

[0022] There are numerous possibilities regarding the remaining design of the power transmission device. This further includes a starting element, preferably in the form of a hydrodynamic component, in particular a hydrodynamic speed / torque converter. The entire power transmission device can be designed as at least a two-channel, preferably also as a three-channel unit. The two-channel unit is characterized in that the actuating device of the switchable clutch device is not assigned a separate chamber that can be pressurized with pressure medium; instead, the pressurization occurs as part of the control of the flow guidance and the pressure conditions.The power transmission device is characterized by at least two connections: a first connection coupled to the working chamber of the hydrodynamic component and a second connection connected to an interior space formed by a housing that is non-rotatably coupled to the impeller of a hydrodynamic component. Designs with a three-channel design are characterized in that the actuating device, in particular the piston element, is assigned at least one chamber that can be actuated with pressure medium and can be supplied with operating fluid as required.

[0023] However, in versions with a two- or three-channel design, it is sometimes provided that the input formed by the housing or its function is taken over by elements connected to it in a rotationally fixed manner, in particular hub elements, for example, in order to arrange the actuating device. At least one axial bearing is provided between the input and the output, preferably between the elements connected to it in a rotationally fixed manner in the form of a damper hub connected to the input and referred to as a housing or piston hub, and the damper output. This utilizes an already existing component and assigns it an additional function to increase the functional concentration.

[0024] The inventive solution is explained below with reference to figures, which show the following in detail: Fig. 1 illustrates a first embodiment of an axial support according to the invention using a section of an axial section of a force transmission device; Fig. 2 illustrates, using a section of an axial section of a force transmission device, a second embodiment of an axial support according to the invention with partial utilization of the axial bearing surface; Fig. 3 illustrates a third embodiment of an axial support according to the invention using a section of an axial section of a force transmission device.

[0025] The Fig. 1 illustrates, in an axial section, a first embodiment of a power transmission device 1 which can be rotated about an axis of rotation R and with, according to the invention, the axial forces acting in the direction of the drive machine being dissipated via a bearing arrangement 2, comprising at least one axial bearing 3. The power transmission device 1 comprises at least one input E and one output A, wherein, in the embodiment shown, at least one starting element 4 in the form of a hydrodynamic component 5 is provided between these in the power flow, and a device for at least partially bridging the power flow via the hydrodynamic component 5 in the form of a switchable clutch device 6. The switchable clutch device 6 is therefore also referred to as a lock-up clutch. A device 7 for damping vibrations is arranged downstream of this in the power flow between input E and output A and, in the embodiment shown, also downstream of the hydrodynamic component 5.The device 7 can be designed in various ways and comprises at least two damper parts 10, 11 coupled to one another via means 8 for torque transmission and means 9 for damping coupling, a damper input and a damper output, which are rotatable relative to one another to a limited extent in the circumferential direction. The function of the means 8 for torque transmission and the means 9 for damping coupling can be performed by the same components, in the case shown, spring units. Depending on the design, the device 7 for damping vibrations can be a single damper arrangement or a plurality of damper assemblies D1 to Dn connected in series and / or parallel. The first damper part 10, which also forms the damper input in the power flow from the input E to the output A, is connected in a rotationally fixed manner to the switchable clutch device 6.The second damper part 11, which forms the damper output in this force flow direction, is in the case shown non-rotatably connected to the output A of the power transmission device 1 or to an element non-rotatably coupled thereto, in particular a damper hub 12.

[0026] In the case illustrated, the device 7 for damping vibrations is designed, for example, as a two-stage damper, comprising a first damper arrangement D1 and a second damper arrangement D2, which are connected in series. Both damper assemblies D1 and D2 are arranged at different diameters, viewed in the radial direction. The first damper part 10 forms the input of the first damper arrangement D1. In the case illustrated, the damper part 10 is designed in the form of drive plates 13 and 14, which are connected to one another in a rotationally fixed manner and are arranged at a distance from one another in the axial direction. The output of the first damper arrangement D1 is formed by a flange 15, which is arranged in the axial direction between the two drive plates 13 and 14. This simultaneously forms the input of the second damper arrangement D2.The output of the second damper arrangement D2 is in turn formed by two drive plates 16 and 17 which are coupled to one another in a rotationally fixed manner and which simultaneously form the second damper part 11, which functions as the damper output and is connected in a rotationally fixed manner to the output A of the power transmission device 1. Other designs of the device 7 for damping vibrations, in particular with regard to the design and arrangement of the individual damper parts 10, 11 and the means 8 for torque transmission and 9 for damping coupling, are also conceivable. What is crucial is that the damper input, which here is formed by the damper part 10, is arranged and designed in such a way that it is supported in the axial direction directly via a bearing arrangement 2, in particular an axial bearing 3 at the input E of the power transmission device 1 or an element directly coupled to it in a rotationally fixed manner, here the hub 18. In the design shown in . Fig. In the particularly advantageous embodiment shown in Figure 1, the bearing arrangement 2, in particular the axial bearing 3, which is already arranged between the damper hub 12 and the hub 18, is used for this function for axial support. The axial bearing 3 is arranged between the input E, in particular the hub 18, and the first damper part 10 and the damper hub 12. For this purpose, the first damper part 10, in particular the drive plate 13, is designed such that it at least partially overlaps the bearing arrangement 2, in particular the axial bearing 3, in the radial direction, with at least indirect contact, preferably direct contact, with the axial bearing surface 34.

[0027] In the illustrated case, the drive plate 13 of the first damper part 10 of the damper input extends radially toward the damper hub 12. The damper hub 12 is designed such that it comprises at least two sub-regions, a first outer periphery forming sub-region 19 and a second outer periphery forming sub-region 20, which are arranged directly adjacent to one another and are characterized by different diameters. The diameters are designated d here. 19 and d 20In this case, the axial bearing 3 is arranged in the area of ​​the first sub-area 19 forming the outer circumference and, when viewed in the installed position, is arranged between the hub 18 and the end face 13.1 of the driving plate 13 which is aligned therewith. The driving plate 13 extends in the area of ​​its inner circumference 21 up to the outer diameter which can be described as the outer circumference of the sub-area 19. The driving plate 13, in particular the end face 13.1, is supported over a portion of its extension in the radial direction on the axial bearing surface 34 of the bearing arrangement 2. The sub-area 20 forming the outer circumference forms, with the sub-area 19 forming the outer circumference, an annular contact surface 22 which is aligned in the axial direction and runs in the circumferential direction and on which the end face 13.2 of the driving plate 13 is supported over a portion of its radial extension.As a result, the forces acting in the axial direction at the damper input, in particular the damper part 10, can be introduced into the hub 18 or 12 depending on the direction of force introduction.

[0028] The basic structure of the illustrated power transmission device corresponds to a so-called three-channel arrangement. The switchable clutch device 6 is designed as a frictionally engaged, wet-running multi-plate clutch, comprising a first clutch part 6E, which is at least indirectly connected in a rotationally fixed manner to the input E, and a second clutch part 6A, which is at least indirectly connected, here via the vibration damping device 7, to the output A of the power transmission device 1. The first and second clutch parts 6E, 6A can be brought into operative connection with one another at least indirectly by means of an actuating device 23.In the illustrated case, each of the clutch parts 6E and 6A comprises a plurality of friction surface-bearing and / or friction surface-forming elements which are mounted on a carrier so as to be displaceable in the axial direction and rotationally fixedly coupled thereto, wherein the coupling to the connection elements input E and the device 7 for damping vibrations is achieved by coupling the respective carriers of the clutch parts 6E and 6A to them. The actuating device 23 comprises at least one pressure-medium-actuated piston element 24 which is rotationally fixedly coupled to the input E and is guided so as to be displaceable in the axial direction relative thereto. In the illustrated case, the piston element 24 is guided in a pressure- and liquid-tight manner on the carrier of the first clutch part 6E, which is designed as an outer disk carrier, and on the outer circumference of the hub 18 so as to be displaceable in the axial direction.The rotationally fixed coupling takes place here in the area of ​​the inner circumference 25 of the piston element 24 with the hub 18 and is designated 26. In the illustrated case, the rotationally fixed connection is designed as a positive connection, in particular an intermeshing toothing.

[0029] The pressure- and fluid-tight guidance is achieved via appropriately arranged sealing devices 27 and 28 in the area of ​​the outer circumference and the inner circumference 25 of the piston element 24 on the connecting elements. A chamber 29, which can be pressurized with pressure medium, is formed between the piston element 24 and the inlet E. A connection A3 is assigned to this chamber. The adjusting movement of the piston element 24 and thus the actuation of the individual coupling parts 6E and 6A is achieved via the pressure difference at the piston end faces 24.1 and 24.1 facing away from one another and thus the corresponding prevailing pressures in the interior 30 of the power transmission device 1 and the chamber 29, which can be pressurized with pressure medium.

[0030] In the illustrated case, the power transmission device 1 is designed as a three-channel arrangement comprising at least three connections, wherein connection A3 is assigned to the chamber 29 to which pressurized medium can be applied, while another connection A1 is coupled to the working chamber AR of the hydrodynamic component 5 and connection A2 to the interior space 30. The flow direction within the power transmission device 1 can be controlled by controlling the pressure conditions and the flow of operating fluid. Due to the pressure- and liquid-tight demarcation of the chamber 29 to which pressurized medium can be applied from the interior space 30, the actuating device 24 can be pressurized as desired, regardless of the conditions at the other connections A1 and A2.

[0031] The hydrodynamic component 5 of the power transmission device 1 is designed as a hydrodynamic speed / torque converter, comprising a pump wheel P, which is at least indirectly connected in a rotationally fixed manner to the input E of the power transmission device or to an element coupled thereto in a rotationally fixed manner, and a turbine wheel T, which forms the working chamber AR with the pump wheel P. Furthermore, hydrodynamic speed / torque converters include at least one reaction element in the form of a stator L.

[0032] The element forming the input E and coupled thereto in a rotationally fixed manner is formed by a component or assembly forming the housing 31 of the power transmission device 1. The housing 31 is designed and arranged such that it is connected in a rotationally fixed manner to the pump impeller P, wherein the connection is made force-fitting, form-fitting, or preferably non-detachably by means of a welded connection. Furthermore, the housing 31 is designed and arranged such that it encloses the switchable clutch device 6 and the device 7 for damping vibrations in the axial and circumferential directions, forming the interior space 30. Connected in a rotationally fixed manner to the housing 31 is the hub 18, which is also referred to as the piston hub due to the support of the piston element 24. The power flow within the power transmission device 1 can occur either in a first power branch via the hydrodynamic component 5 alone.In this case, the switchable clutch device 6 is not actuated. Due to the coupling of the turbine wheel T with the damper input and thus the damper part 10, the device 7 for damping vibrations 7 is also connected downstream of the hydrodynamic component in the power flow. In a second operating mode, the power flow can be directed to output A via the switchable clutch device alone, bypassing the hydrodynamic component 5, while in a third case the power flow in power split occurs via both in appropriate portions. In particular, when the switchable clutch device 6 is actuated, high axial forces arise at the damper input and thus damper part 10, which can impair the functioning of the device 7 for damping vibrations and can only be dissipated via additional components.

[0033] The inventive solution of supporting the damper input via the bearing assembly 2, in particular the axial bearing 3 on the hub 18 and thus the input E, optimally transmits the forces to the components arranged on the engine side without the need for any additional components. Preferably, the bearing assembly 2, which in known designs is arranged between the individual hubs 18 and 12 anyway, is used in the form of an axial bearing, thus eliminating the need for additional retaining elements. In particular, the notch effect caused by the groove required for the retaining ring can be eliminated, and an optimal support surface for the drive plate 13 in the radial direction is provided.

[0034] Clarifies the Fig. 1 shows an embodiment in which the support or axial bearing surface 34 of the axial bearing 3 is preferably completely covered by the driving plate 13, in that the axial bearing 3 is arranged directly between the end faces 18.1 of the hub 18 and 13.1 of the driving plate 13, which face each other in the axial direction, and thus of the damper input, which is provided by the design of the driving plate 13 which is drawn in the radial direction up to the area of ​​the partial area 19. Fig. 2 a further development according to Fig. 1, in which only a partial overlap of the radial extent of the axial bearing surface 34 of the axial bearing 3 and the corresponding end face 13.1 of the drive plate 13, which is supported on this face, and thus of the damper part 10, is provided. The structure of the power transmission device 1 essentially corresponds to that shown in the Fig. 1, which is why the same reference numerals are used for identical elements. The axial bearing 3 is arranged between the hub 18, which is connected in a rotationally fixed manner to the input E, and the damper hub 12. Only a partial area of ​​the axial bearing surface 34, which points in the axial direction and extends in the radial direction and is designed as an annular surface in the circumferential direction, serves to directly support the damper part 10, in particular the drive plate 13. For this purpose, the damper hub 12 has at least one further third partial area 35, which forms an outer circumference and is arranged between the partial areas 19 and 20, and an axial contact surface 36 facing the partial area 19 for that part of the axial bearing surface 34 which is not intended for the direct support of the damper part 10.The third sub-area 35 is characterized by a diameter that is larger than that of the first sub-area 19 and smaller than that of the second sub-area 20. The contact surface 22 on the second sub-area 20 supports the damper part 10, in particular the drive plate 13 on the end face 13.2.

[0035] In contrast, the Fig. 3 a further development of a design according to Fig. 1, which is essentially characterized by the arrangement of the support of the damper input and thus of the damper part 10 in its design. The remaining structure corresponds to that in the Fig. 1, which is why the same reference numerals are used for the same elements. Fig. 3, the design of the drive plate 13 in the area of ​​its inner circumference is characterized by a projection oriented in the axial direction, which is designated 32 here and forms an axial contact surface 33 for contact with the damper hub 12. Here, too, the damper hub 12 is characterized by areas of different diameters or by different outer circumference-forming partial areas 19 and 20, which differ from one another in terms of their dimensions and profiles. In this design, too, the drive plate 13 is drawn in the radial direction into the area of ​​the outer circumference-forming partial area 19, wherein the axial projection 32 simultaneously forms a radial contact surface for contact with the outer circumference-forming partial area 19. The projection 32 extends from the end face 13.1 in the opposite direction to the inlet E, so that the end face 13.1 is fully available for support on the axial bearing 3. Here, too, there is an overlap of the drive plate 13 and the axial bearing 3 in the radial direction.

[0036] The solution according to the invention is not limited to the Fig. 1 to 3. These merely represent variants for the specific design of a support for a damper part, which is connected in a rotationally fixed manner to the output of the switchable clutch device, at the input E of the power transmission device 1. In the Fig.The designs of the damper input shown in Figures 1 to 3 are designed as a drive plate. Designs as a flange are also conceivable here, for which the inventive solution applies analogously. The design of the axial bearing 3 itself can be varied. According to the invention, rolling bearings are used, in particular in the form of needle bearings, or plain bearings, although in this case corresponding high-quality sliding surfaces must be provided or sliding surfaces of a corresponding size must be provided. In all of these designs, the axial forces introduced into the torsion damper from the clutch side can be transmitted and the uncontrollable frictional moments otherwise generated therein can be eliminated. Complex additional components such as retaining rings and the provision of corresponding grooves can be avoided.The design of the damper input part in the area supported in the axial direction is very simple and is not subject to any special requirements.

Claims

[1] Power transmission device (1) with at least one input (E), one output (A), a switchable frictional coupling device (6) arranged in the power flow between them and a device (7) arranged downstream of this for damping vibrations, comprising at least two damper parts (10, 11) which are rotatable relative to one another in the circumferential direction to a limited extent and are coupled to one another via means (8, 9) for torque transmission and / or damping coupling and with means for discharging the axial forces caused by the actuation of the switchable coupling device (6) from the device (7) for damping vibrations, characterized byin that the means for diverting comprise at least one axial bearing (3) between the damper part (10) connected in a rotationally fixed manner to the switchable clutch device (6) and the input (E) of the power transmission device (1) or an element connected in a rotationally fixed manner to the latter, wherein the axial bearing (3) is designed as a rolling bearing or as a plain bearing, wherein the output (A) or an element connected in a rotationally fixed manner to the output (A) comprises at least two partial regions (19, 20), each forming an outer circumference, wherein the first partial region (19) corresponds to the arrangement region of the axial bearing (3) and the second partial region (20) forms an axial contact surface (22) for the damper part (10) on its end face (13.2) directed away from the axial bearing (3), wherein the first partial region (19) and the second partial region (20) are arranged directly adjacent to one another in the axial direction. [2] Power transmission device (1) according to claim 1, characterized bythat the function of the axial bearing (3) for discharging the axial forces caused by the actuation of the switchable clutch device (6) is at least partially taken over by an axial bearing arranged between the input (E) or an element connected thereto in a rotationally fixed manner and the output (A) or an element connected thereto in a rotationally fixed manner. [3] Power transmission device (1) according to claim 1 or 2, characterized by that the damper part (10) connected in a rotationally fixed manner to the switchable clutch device (1) is arranged and designed in such a way that it extends in the radial direction into the region of the radial extension of an axial bearing surface (34) of the axial bearing (3) with at least indirect, preferably direct contact with at least a partial region of this axial bearing surface (34). [4] Power transmission device (1) according to one of the preceding claims, characterized bythat the axial contact surface (22) formed by the second partial region (20) corresponds in the radial direction to the extension of the axial bearing surface (34) in the radial direction. [5] Force transmission device (1) according to one of the preceding claims, characterized by that the damper part (10) comprises, in the region of its inner circumference (21), an annular projection (32) directed in the axial direction away from the axial bearing (3), which has an axial contact surface (33) for contact with the axial contact surface (22) on the second partial region (20). [6] Power transmission device (1) according to one of claims 1 to 5, characterized bythat the input (E) of the power transmission device (1) or an element connected thereto in a rotationally fixed manner is formed by a housing part (31), to which a hub (18) for centering and / or guiding the actuating device (23) of the switchable clutch device (6) is connected in a rotationally fixed manner and the axial bearing (3) is arranged between the damper part (10) and the hub (18). [7] Power transmission device (1) according to one of claims 1 to 6, characterized by that the element which is connected in a rotationally fixed manner to the output (A) is formed by a damper hub (12) which is connected in a rotationally fixed manner to the damper part (11) forming the damper output. [8] Power transmission device (1) according to one of claims 1 to 7, characterized by that it comprises a starting element (4), and the switchable clutch device (6) and the starting element (4) can be switched at least in parallel. [9] Power transmission device (1) according to claim 8, characterized bythat the starting element (4) is designed as a hydrodynamic component (5). [10] Power transmission device (1) according to claim 8 or 9, characterized by in that the actuating device (23) of the switchable clutch device (6) comprises a pressure-medium-actuated piston element (24) which is guided in a pressure- and liquid-tight manner to form a chamber (29) which can be pressurized with pressure medium at the inlet (E) and / or an element (18) which is coupled non-rotatably thereto, the power transmission device (1) is designed as a three-channel unit, comprising a first connection (A1) for coupling to a working chamber (AR) of the starting element (4), a second connection (A2) for coupling to an interior space (30) enclosed by a housing (31) and a further third connection (A3) for coupling to the chamber (29) of the actuating device (23) which can be pressurized with pressure medium.

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