WO2008064641A1 - Power transmission device - Google Patents

Abstract

The invention relates to a power transmission device (1) to be interposed in a drive train between a driving engine and a transmission. Said power transmission device comprises an input (E) and an output (A) configured by a shaft, and two switchable clutch devices (2, 5) - a first and a second clutch device - that are arranged in an interior (10) that is enclosed by a housing (56) and defines a first pressure compartment (55), every clutch device having at least one piston element (4, 7) that can be supplied with a pressure medium. The invention is characterized in that both piston elements are guided on the output or an element (28) that is non-rotatably connected thereto, while defining a second pressure compartment (8) that is pressure and liquid-tight in relation to the interior. The individual pressure compartments can be supplied with a pressure medium via intersecting channels (16, 17) that are arranged off-set from one another in the peripheral direction in the output or the non-rotatably connected element.

Description

 Kraftübertraqunqsvorrichtung

The invention relates to a power transmission device, in detail with the features of the preamble of claim 1.

Power transmission devices disposed between a prime mover and a transmission assembly are known in a variety of prior art designs. These usually include an input and at least one output, wherein the input at least indirectly, that is directly or via further transmission elements with the drive motor is coupled and at least one output connected to a power transmission device downstream transmission unit, usually a change gear is and is formed by a transmission input shaft. Between the input and the output, a hydrodynamic component, preferably in the form of a hydrodynamic speed / torque converter, is arranged. This comprises at least one impeller and a turbine wheel. To bridge the hydrodynamic power transmission, a device is provided, which is also called bridging clutch. This comprises a first coupling part and a second coupling part, which are at least indirectly engageable with each other in operative connection. The lock-up clutch serves for the coupling between the input or the connection between the input and the impeller and the turbine wheel. The actuation of the switchable coupling via an actuating device, which comprises in the simplest case, an adjusting device in the form of a pressurizable piston element. Depending on the design of the hydrodynamic speed / torque converter or the entire power transmission device is designed as a two-channel or three-channel unit. When training in three-channel design while the actuator is subjected to a separately controllable pressure. The remaining connections to the working space of the hydrodynamic component and the spaces between hydrodynamic speed / torque converter and lockup clutch and actuator are then either centripetal or centrifugal flows, depending on the coupling of the connections in a pressure medium supply system to achieve an internal circuit, external to self-adjusting flow circuit in the hydrodynamic speed / torque converter in operation and is guided either within the power transmission device or externally. As a rule, the power in an operating range is transmitted purely hydrodynamically via the hydrodynamic power branch. In this case, the power flow between the input and the output via the hydrodynamic component takes place. The primary impeller acting as impeller is coupled directly to the engine and the turbine wheel to the output or the input of a downstream Change gear, which can be done with the interposition of a damping device. In order to avoid the disadvantages of hydrodynamic power transmission, which arise at higher speeds, especially when used in vehicles, the lock-up clutch is activated and the power is transmitted between the input and the output of the power transmission device mechanically, bypassing the hydrodynamic power branch. When idling the engine, especially in overrun, the lockup clutch can disconnect the prime mover from the output in the mechanical branch. However, if the hydrodynamic component remains filled, which is the case with the hydrodynamic speed / torque converter even in the bridged state, a torque is introduced into the hydrodynamic component during coasting, which in turn leads to losses when the engine is idling. Furthermore, torque shocks are introduced from the side of the output in the hydrodynamic component. For decoupling the drive machine from the transmission therefore a coupling device is provided, which serves for decoupling of the pump impeller and thus for decoupling the drive machine of a power transmission device downstream transmission unit. The impeller clutch is required only for separation in this operating range. This is often arranged in an area that leads to increase the required installation space in the radial or axial direction. To control this further coupling device corresponding pressure chambers are to be provided, which at least one connection is to be assigned to the supply of pressure medium, for which corresponding further channels are to be provided.

The invention is therefore based on the object, a power transmission device of the type mentioned in such a way that it is designed as a multi-function converter, that is, at least one more switchable clutch device in addition to the lock-up clutch and further the already known for power transmission devices three-channel principle is maintained, that is more than three connections should be avoided if possible.

The solution according to the invention is characterized by the features of claim 1. Advantageous embodiments are described in the subclaims.

A power transmission device for arrangement in a drive train between a prime mover and a transmission comprising an input and an output formed by a shaft and two switchable clutch devices arranged in an inner space enclosed by a housing and forming a first pressure chamber - a first te and a second coupling device - each having at least one acted upon by a pressure medium piston element is inventively characterized in that both piston elements to form a second pressure-tight and liquid-tight against the other interior pressure chamber at the output or a non-rotatably coupled thereto element are guided and the individual pressure chambers via in the output or with this rotatably coupled element in the circumferential direction offset from one another and intersecting channels can be acted upon with pressure medium.

The solution according to the invention allows a space-saving arrangement of the individual actuating devices and an independent supply of individual pressure chambers with operating or pressure medium, usually oil. The term pressure chamber generally stands for a space that can be acted upon by any pressure.

According to a particularly advantageous embodiment, the second switchable coupling device on the first piston element, i. arranged the piston member of the first coupling means and the second piston member on the first piston member guided to form the pressure medium acted upon pressure chamber in the axial direction displaceable. The first piston element is characterized by a high functional concentration.

Preferably, a plurality of the individual channels - first channels and / or second channels are provided for uniform supply, which are arranged in the circumferential direction alternately to each other. To avoid imbalances, the arrangement of the channels takes place in an advantageous manner in the circumferential direction symmetrically.

The supply of the second pressure chamber with pressure medium takes place through the first pressure chamber. For this purpose, a subdivision of the first pressure chamber in the connection region in the axial direction into two sub-chambers, which are again coupled to each other via at least one channel. The connection channels extend in the axial direction through the connection element or guide element for the individual piston elements, so that the partial pressure chambers are coupled to one another on both sides of the piston arrangement. Preferably, a plurality of such axially extending channels are provided in the circumferential direction. These are arranged spaced from each other. Between two adjacent channels arranged at least one connecting channel for coupling a central supply line with the second pressure chamber in the radial direction is aligned. This means that the individual pressure chambers are closed in the circumferential direction. - A - other offset arranged and projecting in a plane intersecting channels with resources or control means are acted upon. The solution according to the invention thus makes it possible on the one hand to provide a high functional concentration with respect to the arrangement and mounting of the individual piston elements and the individual coupling devices, while maintaining the three-channel principle, a supply of the two piston elements of the two switchable coupling devices can be done separately by the both piston elements are displaceable relative to each other in the axial direction and by adjusting the pressures or pressure difference of the individual surrounding the piston assembly pressure chambers.

Depending on the design of the power transmission device and the functions of the individual shiftable clutch devices, the connection element for supporting or guiding the piston arrangement or the individual piston elements can either be a transmission input shaft of a downstream transmission unit which simultaneously forms the output of the power transmission device, a rotation-proof one Transmission input shaft coupling element, for example in the form of a hub element. In the latter case, the hub member itself rotatably with the transmission input shaft directly or at least indirectly, that is connected via other transmission elements, such as a device for damping vibrations. The hub element may be the hub which can be coupled to a turbine wheel or, for example, a hub element of a device for damping vibrations, in particular of the hub element connected to the secondary part.

In the case of the guide directly on the transmission input shaft, this is provided in the radial direction in the guide region with a projection which extends in the axial direction at least over the entire displacement range of the piston assembly. This solution offers the advantage that the number of sealing devices required for sealing the individual pressure chambers with one another, in particular the first and second pressure chambers, can be kept low. In contrast, the design with support on a separate intermediate hub, which is either rotatably coupled to the transmission input shaft or at least indirectly via further transmission elements with this, in which case at least one pressure and liquid-tight guide against the first pressure chamber in the connection area for the second Provide pressure chamber is the advantage that the transmission input shaft can still be designed very simple and compact and is suitable for a variety of different applications and the appropriate hub design is set only for the specific configuration in this embodiment. With regard to the cross-sectional geometry as well as the guidance of the individual connection channels, there are no restrictions. The connecting channel for the individual pressure chamber areas of the first pressure chamber is preferably aligned parallel to the axis of rotation and thus extends quasi in the horizontal direction. Also conceivable, depending on the design and space conditions, are inclined formations over the extension in the axial direction, as well as embodiments of the channel with subsections which are characterized with respect to their position relative to one another by changes in direction. This can be optimally influenced on the structural conditions. By analogy, this also applies to the connection channel designed for coupling with the second pressure chamber, viewed in the radial direction in the installed position. Here, too, positional differences of an intentional or unintended nature can be realized and compensated by the corresponding guidance.

With regard to the number and type of arrangement, there are a number of possibilities. In this case, embodiments in the circumferential direction with a symmetrical arrangement are preferable to those with an asymmetrical arrangement in order to introduce no additional imbalances into the system. Preferably, the respective connection channels for the sub-chambers of the first pressure chamber and for the second pressure chamber are each arranged alternately in the circumferential direction with uniform distances from each other.

With regard to the type of guidance of the second piston element on the first piston element, there are a large number of possibilities. In this case, the guide can be made on a partial area forming an inner circumference or on an outer area forming an outer circumference. However, this depends on the installation situation and the function of the individual piston elements with respect to the coupling devices associated therewith.

The piston assembly of the two piston elements can be designed such that the individual piston elements are characterized in terms of the closing direction of the individual coupling devices by the same actuating direction or different actuation directions. The former case has the advantage that the actuation of the one coupling device upon actuation of the second pressure chamber simultaneously causes an opening of the other coupling device or a pressure counteracting the closing pressure is generated on the other piston element. This embodiment is quasi characterized by a kind of positive coupling, which is determined by the pressure in the second pressure chamber and the ambient pressure, ie in the interior. If the direction of actuation of one of the two piston elements is opposite to one another, at least on one piston element, a further piston surface defining the pressure chamber is to be provided, which allows the piston element to be acted upon via the first pressure chamber.

The power transmission devices are generally hydrodynamic-mechanical power transmission devices, that is, these are characterized at least by the possibility of power transmission via a first power branch and a second power branch, wherein the first power branch through the hydrodynamic power transmission between the input and at least one output Power transmission device is characterized, while the second power branch includes the purely mechanical power transmission between the input and the output. The hydrodynamic power transmission is realized by the arrangement of a hydrodynamic component. This comprises at least one pump wheel which can be coupled at least indirectly to the input and a turbine wheel which can be coupled at least indirectly to the output, this being either free from a stator in the form of a hydrodynamic coupling or with at least one stator as a hydrodynamic speed / torque converter is. The latter offers the advantage in the starting range of stepless speed and simultaneous torque conversion between input and output.

Depending on the type of multi-function converter, the first clutch device may be a so-called pump or primary wheel clutch. This allows an optional coupling or decoupling of the impeller from the input. Furthermore, it is conceivable to design the first coupling device as a turbine coupling. In this case, the turbine wheel is selectively decoupled from the output, in particular the transmission input shaft, or can be coupled thereto. The former design has the advantage that in power transmission between input and output, the hydrodynamic component is completely decoupled in the bridged state from the input, that is no entrainment of the impeller takes place. The second embodiment with a possible turbine wheel clutch offers the advantage of a complete decoupling of the hydrodynamic component from the transmission output shaft in overrun mode, so that the idling losses can be considerably reduced here, in particular during idling. In this case, in the case of a version with a pump wheel clutch, a separate co-rotating housing is required, whereas in designs with turbine wheel coupling this can be dispensed with and the housing is formed by an element coupled to a rotationally fixed pump shell. Due to the formation of a pressure chamber by combining the two piston elements of the individual coupling devices to form a piston arrangement, the individual coupling devices can be arranged in the smallest possible space. Preferably, the arrangement takes place in the axial direction next to each other with minimal offset. Accordingly, the individual piston surfaces are interpreted. As a rule, the piston elements themselves are disc-shaped elements which, viewed in the axial direction in cross-section, are characterized by a corresponding shaping in order to ensure the possible contact surfaces or contact surfaces. In the radial direction, the individual coupling devices with different diameters, in particular outer and inner diameters, are formed, so that the simplest possible configuration of the first piston element with connection possibility for the second coupling device is provided. With regard to the concrete embodiment of the coupling possibilities between the first coupling part of the second coupling device and the piston element, there are a plurality of possibilities. This applies analogously also for the connection of the first coupling part to the first piston element. Preferably non-positive or positive connections are selected, which ensure a rotationally fixed connection in the circumferential direction, but viewed in the axial direction in cross-section, ensure a displacement.

The power transmission device according to the invention is suitable for use in drive trains, in particular for coupling with a prime mover and a transmission. This is characterized by three pressure chambers, a first pressure chamber, which is formed by the inner circumference of the housing and the outer circumference of the hydrodynamic component, a second pressure chamber, which is formed by the piston assembly and a third pressure chamber, of the hydrodynamic component, in particular the working space, is formed. Each of these pressure chambers is associated with a corresponding port for coupling to a Betriebsmittelversorgungs- or leadership system. The term connection is to be understood in terms of its function and not in terms of a concrete structural design. It is therefore understood that a plurality of corresponding terminals can be provided viewed in the circumferential direction.

The solution according to the invention is explained below with reference to figures. The following is shown in detail:

FIG. 1 illustrates, on the basis of an axial section, a particularly advantageous embodiment of a power transmission device, in particular a multi-function transducer unit according to a first embodiment; Figure 2 illustrates on the basis of a section in a view from the right, the resource guide in the first and second channels;

FIG. 3 illustrates another possible second embodiment of a power transmission device designed according to the invention with a clutch device designed as a turbine wheel clutch.

1 shows in an axial section a particularly advantageous embodiment of an inventively designed power transmission device 1. This is arranged in a drive train between a prime mover, not shown here and a transmission not shown here in detail and serves the power, in particular torque transmission. For this purpose, the power transmission device 1 at least one input E and an output A. The input E is at least indirectly coupled to the drive machine, not shown here, while the output A with an output, usually one of the power transmission device 1 downstream transmission is connected and is formed by a shaft, in particular transmission input shaft 22. Between the input E and the output A, a first switchable coupling device 2 is provided. This has an adjusting device 3, comprising at least a first pressurizable piston element with pressure element 4. Furthermore, a further second switchable coupling device 5 is provided. Each of the switchable coupling devices - first switchable coupling device 2 and second switchable coupling device 5 - comprise at least one first coupling part 2.1 or 5.1 and a second coupling part 2.2 or 5.2, at least indirectly can be brought into operative connection with each other. The active compound is generated via adjusting devices 3 and 6 respectively. Both coupling devices 2 and 5 are arranged in a, an interior 10 enclosing housing 56. The interior 10 acts as a pressure medium acted upon first pressure chamber 55. According to the invention, both piston elements 4 and 7 were supported in a piston assembly 9 to form a further second pressure medium acted upon chamber 8, which is pressure and liquid-tight against the first pressure chamber 10, on a common connection element at least indirectly at the output A from. For this purpose, the second coupling device 5 is arranged on the adjusting device 3 of the first switchable coupling device 2, in particular one of the coupling parts, here 5.1 mounted on the pressurizable with pressure medium first piston member 4. Furthermore, the second piston element 7 of the second switchable coupling device 5 on the first piston element 4 can be displaced in the axial direction to form the chamber 8 which can be subjected to pressure medium. leads. The two piston elements 7 and 4 thereby form a piston arrangement 9, which is arranged in the interior 10 of the force transmission device 11 functioning as the first pressure chamber 55, wherein the first piston element 4 can be subjected to pressure medium via the interior 10. In this case, the inner space 10 and the pressure medium can be acted upon by the respective chamber 8 at least one port 11 and 12 are assigned, via which the pressure medium guide, in particular resource management. The term connection is to be understood in the functional sense and not limited to a specific structural design. Connection means only a connection to the respective interior 10 or to the chamber 8 toward the purpose of pressurization, in particular supply o- the removal and / or application of pressures. The chamber 8 is thereby limited as already stated by the two piston elements 4 and 7, wherein the second piston member 7 pressure and liquid-tight on the first piston member 4 is performed. Further, to form the chamber 8, the second piston element 7 at the output A or on a non-rotatably coupled to the output A element also pressure and liquid-tight in the axial direction, for example, via a sealing device 13.1 in the region of the radial outer periphery 14 of the second piston element Directed displaced. This takes place here, for example, via a further sealing device 13.2, which is arranged in the radial direction in the region of the inner circumference or a partial region of the piston element 7 which forms an inner circumference and which is designated here by 15. The chamber 8 is thus virtually in the interior 10 and is enclosed by the pressure chamber 55 formed. So that a corresponding pressure medium can be applied, intersecting channels 16 and 17 are provided on the radially inwardly located connection elements for the pressure chambers for acting on the first and second piston elements 4, 7, viewed in the circumferential direction of the connection element are arranged offset to one another, that is, are fluidically decoupled from each other. These channels 16 and 17 are guided by the piston elements 4 and 7 supporting elements in the radial or in the axial direction, in which it is the output A forming the transmission input shaft 22 or a non-rotatably coupled with this hub member 28.

1 illustrates an embodiment in which the first shiftable clutch device 2 is designed as a so-called impeller clutch 18, while the second shiftable clutch device 5 is designed as a lock-up clutch 19. In this case, the lockup clutch 19 functions with regard to the bypassing of a hydrodynamic power branch, which is formed by a hydrodynamic component 20, which is preferably in the form of a hydrodynamic speed / torque converter 21 and at least a first as impeller P during power transmission from the input E to the output A acting paddle wheel and a second, at power transmission between a gear E and output A acting as a turbine wheel and at least indirectly connected to the output A paddle wheel comprises. When designed as a hydrodynamic speed / torque converter 21 at least one stator L is also provided. The hydrodynamic speed / torque converter 21 serves for the simultaneous conversion of speed and torque during power transmission. In embodiments of hydrodynamic components 20 in the form of a hydrodynamic coupling not shown here, this is free of a stator and acts only as a speed converter at the same torque. The impeller clutch 18 is arranged between the input E and the impeller P and is used for the selective coupling or decoupling of the impeller P of this. The connection between input E and impeller assembly 18, for example, via a co-rotating housing part 56, which can simultaneously take over the function of the input E or is connected to another element for non-rotatable coupling with this. The second switchable coupling device 5 acting as a bridging clutch 19 serves to bypass the power transmission via the hydrodynamic component 20 and thus the direct coupling between the input E and the output A. The output A is in the case illustrated by a shaft which can be coupled to the downstream transmission Also referred to as transmission input shaft 22 is formed. All components, in particular hydrodynamic component 20, first switchable coupling device 2 and second coupling device 5 are arranged coaxially with each other and also coaxial to a rotation axis R of the power transmission device 1. Further, in the case shown, a device 23 for damping vibrations is provided. This is designed as a torsional or torsional vibration damper and comprises at least one damper stage, which of a primary part 24 and a secondary part 25 which are rotatable in the circumferential direction limited relative to each other, is formed, wherein the primary part 24 and secondary part 25 via means 26 for spring and / or damping coupling connected to each other. The means 26 for spring and / or damping coupling can be designed in various ways. In purely mechanical damper versions, the coupling is done only via spring units 27, which in addition to the torque transmission and the function of damping, that is absorption of torque surges take over. In other embodiments, such as combined hydraulic mechanical damper designs, in addition to spring units, for example, with damping medium, in particular fat-filled damping chambers are provided. The concrete selection of the respective device for damping vibrations is at the discretion of the competent expert and also depends on the requirements of the application in detail. This also applies to the specific structural design with respect to the primary part 24 and secondary part 25. It is crucial that the secondary part 25 as the output part of acting as a flexible coupling device 23 for damping vibrations rotatably connected to the output A and The primary part 24 is at least indirectly rotatably coupled to the input E, the coupling depending on the type of power transmission - hydrodynamic or purely mechanical - on the hydrodynamic component 20, in particular the turbine wheel T, with this or a non-rotatably coupled thereto element, in particular connection element, which in turn is rotatably connected to the primary part 24, takes place. In purely mechanical power transmission, the coupling of the primary part 24 takes place with the second coupling part 5.2 of the lock-up clutch 19 and thus the output of the second switchable coupling device 5. In hydrodynamic power transmission, the power transmission takes place by the coupling of the turbine wheel T with the primary part 24 via a hub member 28. This Hub member 28 serves to support the first piston member 4 and further at least indirectly the leadership and support of the second piston member 7. As already stated, the second piston member 7 via the sealing device 13.1 on the first piston member 4 pressure and liquid tight in the axial direction slidably guided and In the case illustrated, the first coupling device 2, in particular the first piston element 4, likewise supports itself on the hub element 28 via the second sealing device 13. 2 in a pressure- and liquid-tight manner relative to the hub element 28 corresponding axial and radial bearing 30 from. This is preferably designed as a sliding bearing. The first piston element 4 is designed such that it forms a plate carrier 31 for the first coupling part 5.1 of the second switchable coupling device 5 in the embodiment of the switchable coupling devices 2 and 5 as frictional coupling devices. Furthermore, this forms a plate carrier 32 for the first coupling part 2.1 of the first coupling device 2, which is designed as a pump gear 18. The second coupling part 2.2 of the first coupling device 2 is at least indirectly rotatably connected to the impeller P. In the case shown, this takes place via the impeller shell 33, wherein the impeller shell 33 acts as a plate carrier 34 for the lamellae of the second coupling part 2.2 of the first coupling device 2. The first piston element 4 of the first switchable clutch device 2 is thus formed in cross section with a projection 35 formed in the axial direction for the realization of said support functions for the individual clutch parts, here 2.1 and 5.1 of the individual switchable clutch devices 2 and 5. Further, on this projection 35, which is viewed in the radial direction in each case as a plate carrier in the formation of the first and second coupling devices 2.5 is formed as a switchable frictional coupling devices 2.5 in the form of multi-plate clutches, the rotationally fixed coupling with the input E, in particular a rotatable housing part 55th This takes place in the illustrated case via a further device 36 for damping vibrations. This also comprises a primary part 37 and a secondary part 38, wherein the primary part 37 at least indirectly rotationally fixed to the input E, in particular is connected to the housing part 55, while the secondary part 38 is connected at least indirectly non-rotatably connected to the piston member 5. Again, the primary part 37 and the secondary part 38 are coupled to each other at least indirectly via means 39 for spring and / or damping coupling and limited to each other in the circumferential direction rotatable limited. Depending on the embodiment, the means 39 for spring and / or damping coupling comprise either only spring units which serve for torque transmission and at the same time for damping or else additional, differently designed damping elements, for example friction damping pairings or chambers which can be filled with damping medium etc.

The non-rotatable connections between the individual elements, depending on the function and requirements solvable or non-detachable, for example by welding, done. Furthermore, a form or adhesion or a combined mounting is conceivable. In the case of desired axial displaceability, non-rotatable connections preferably take place by means of splined shaft connections. In addition, for the device 23 whose secondary part 25 is rotatably connected via the hub member 29 to the output A, a Verdrehwinkelbegrenzung between the primary part 24 and the secondary part 25 are realized via the hub member 29, for example, arranged on this in the circumferential direction and extending recesses or Projections which engage in the projections or recesses on the primary part 24, wherein the tolerances are dimensioned so that a certain predefined angle of rotation is permitted.

The function of the power transmission device is designed as followsjm essentially two different modes of operation, the power transmission via the hydrodynamic branch in the form of the hydrodynamic component 20 and the purely mechanical power transmission, bypassing the hydrodynamic component 20, in particular the hydrodynamic speed / torque converter. In the former case, the adjusting device 3, in particular the first piston element 7, is actuated and brings the two coupling parts 2.1 and 2.2 of the first switchable coupling with each other in operative connection, so that here a coupling with the input E of the power transmission device 1 is produced, said coupling indirectly takes place via the device 36 for damping vibrations. This, in particular their secondary part 38, is rotatably coupled to the piston member 4, in particular the projection 35. The coupling can be designed in many forms. In order to realize an axial displaceability of the piston element 4 or a relative movement between the secondary part 38 of the device 36 and the piston element 4, this is for example designed as a rotationally fixed connection with axial displaceability, in the simplest case chosen here a spline becomes. In the illustrated case, the secondary part 38 has in the region of its inner circumference 40 toothed elements 41 which are in engagement with complementary toothed elements 42 on the piston element 4 and the projection 35, wherein the arrangement on a, an outer circumference 43 forming portion of the projection 35 and des Piston element 4 takes place. In this functional state, a contact pressure force is generated via the piston element 4, which brings the individual coupling parts 2.1 and 2.2, in particular the lamellae having them, in operative connection by pressing. Due to the coupling, the pump impeller P is driven and, due to the operating medium present in the working space 57, which is formed by the individual impellers, the turbine wheel T is driven in accordance with the speed / torque conversion via the stator L. The piston assembly 9, which is formed by the two individual piston elements 4 and 7, divided in connection with their coupling to the output A, here via the hub member 28, while the interior 10 in two sub-chambers 10.1 and 10.2, whose size depending on the position of both piston elements 4 and 7 is mutually variable. The connection of these takes place via the channels 16.

From the turbine wheel T, the power is transmitted to the transmission input shaft 22 via the coupling with the turbine hub 28, the primary part 24 of the device 23 for damping vibrations on the secondary part 25 and the hub 29 coupled thereto. In this mode of operation, the second shiftable clutch 5 in the form of the lock-up clutch 19 is not actuated. When desired bridging the hydrodynamic component 20, the lock-up clutch 19 is actuated. For this purpose, the second piston element 7 of the piston assembly 9 is acted upon, in particular the chamber 8 formed by the two piston elements 4 and 7, which is coupled to the connection 12. The supply channel 50 is guided through the transmission input shaft 22 and extends coaxially to the axis of rotation R. From this, the corresponding connecting channel extends to the chamber 8 in the form of a extending in the radial direction of the sub-channel 49, which is arranged in the hub member 28 channel 16 opens into the pressure chamber 8. The first port 11, which serves to couple with the interior 10, is preferably between the transmission input shaft 22, in particular the outer periphery 44 of the transmission input shaft 22, and a support shaft 45, which preferably corresponds to the support shaft for the stator L, is provided. The subdivision of the inner space 10 in the two sub-chambers 10.1 and 10.2 is over the connecting channel 16, which extends substantially parallel to the axis of rotation R through the hub member 28, repealed. Other resource guides are conceivable. The decisive factor here is that at least one individual connecting channel 16 is formed in the axial direction, which can also compensate for differences in height in the radial direction. Preferably, a channel is selected, which preferably runs parallel to the axis of rotation R. By the Druckmittelbeaufschlagung at the desired bridging the piston member 7 is moved in the direction of the second coupling part 5.2 and brings the first and the second coupling part 5.1 and 5.2 in operative connection, so that the rotationally fixed coupling between the first coupling part 5.1 and the primary part 24 of the device 23 for damping is made of vibrations through the second coupling part 5.2. In this case, in the illustrated case, preferably a stop 46 is provided on the first piston element 4, which simultaneously causes pressurization in the chamber 8, the first piston member 4 is claimed to train and in its position relative to the second piston member 7 at a further stop for the piston element 4 is fixed, with an appropriate design of the piston surfaces, the entire piston assembly 9 is free of axial forces on other connection elements. The entire arrangement can furthermore be designed in such a way that the first clutch device 2 is always actuated in the unloaded state, in particular in the unloaded state of the pressure chamber 8, while upon activation of the lock-up clutch 19 due to the pressure setting on the piston element 7 Wheel clutch 18 is solved. The stop 46 is preferably non-rotatably arranged on the piston element 4, in particular the projection 35.

Furthermore, the hydrodynamic component 20 is assigned a further third connection 47 for coupling to the working space 57. Depending on the operating medium guide, the hydrodynamic component 20 can then be flowed through centrifugally or centripetally, that is to say either from the region of the inner diameter to the outer diameter or vice versa. It is crucial that in the resource guide outside of the hydrodynamic component 20 in the power transmission device 1, the exchange between the two sub-chambers 10.1 and 10.2 on the preferably horizontally running transverse bores, in particular the channels 16, while the application of the pressure chamber 8 via the substantially radial Direction aligned channel 17 takes place.

With regard to the specific configuration of the corresponding connection channels 16 and 17, there are no restrictions. In each case, a single such channel may be provided 16 or 17 or a plurality of channels, the latter option is preferably applied. In this case, the individual connection channels 16.1 to 16.n are preferably arranged alternately in the circumferential direction with the connection channels 17.1 and 17.n. As already stated, the connection between the two sub-chambers 10.1 and 10.2 can be realized differently. In the simplest case, this is done via a mounting position in the horizontal direction, that is aligned parallel to the axis of rotation R passage opening. The cross-sectional profile may preferably over the entire axial extent be identical. Changes are also conceivable for influencing the flow conditions. Furthermore, it is conceivable, in particular depending on the structural conditions, to compensate for radial differences via such a connecting channel. By analogy, these statements also apply to the connecting channel 17 for coupling a central supply line 50 with the pressure chamber 8. Preferably, the orientation of the connecting channel takes place directly in the radial direction. In embodiments with additional hub elements 28, an annular circumferential groove 48 is preferably provided in the transition region between the transmission input shaft 22 and the inner circumference of the hub member 28, in which via the first in the transmission input shaft 22 guided sub-channel 49, the central supply line 50 with the corresponding connecting channel 17 in the hub member 28th is coupled. Since the rotationally fixed coupling between the turbine hub, in particular the hub member 28 and the transmission input shaft 22, not directly but indirectly via the device 23 for damping vibrations, here is a seal assembly 52 is provided which seals the pressure chamber 10 relative to 8 in the axial direction.

FIG. 2 shows, in a schematized simplified illustration, a possible channel guidance for the connection channels 16.1 to 16.n and 17.1 to 17.n. in a view from the right in the form of a section from a sectional view through a hub 28. In the illustrated embodiment, it can be seen here a plurality of such channels can be provided, which are arranged alternately in the circumferential direction, and each offset from one another, wherein the alignment in the axial direction is free from the parallel position to each other, so that they substantially intersect or inclined in projecting in a plane extend to each other and extend through the hub member 28.

The embodiment shown in Figure 1 describes the specific embodiment of the subdivision of the inner space 10 by means of the piston assembly 9 and the coupling with the transmission input shaft 22 through the hub member 28 in the two Teilkammem 10.1 and 10.2. It would also be conceivable, depending on the design, a corresponding projection in the radial direction on the transmission input shaft 22 itself, in which case additional sealing measures can be dispensed with, but the corresponding connection channels 16, 17 would have to be pre-drilled.

The actuation of the individual coupling devices 2, 5 is preferably carried out independently of each other by the possible displaceability of the individual piston elements 4, 7 in axia- ler direction relative to each other by the pressure differences between the individual pressure chambers 55, 8 and 57. Here, according to Figure 1, the design is designed such that the piston elements 4 and 7 have the same direction of actuation for closing the coupling devices 2, 5.

1 illustrates an embodiment according to a particularly advantageous embodiment with a pump clutch 18, it is also conceivable to provide a pressure chamber 8 formed between two piston elements 4 and 7 of two coupling devices 2, 5, wherein one of the two coupling devices 2.5 of a so-called Turbine coupling 53 is formed. This embodiment is shown here only highly schematic. Concrete constructive designs are then at the discretion of the competent expert. The first clutch device 2 is formed by the turbine clutch 53. This has a first coupling part 53.1, which is non-rotatably connected to the turbine wheel T and a second coupling part 53.2, which is at least indirectly non-rotatably connected to the transmission input shaft 22. The second clutch device 5 is also formed here by the lock-up clutch 19.

Figures 1 and 3 illustrate only possible embodiments. The embodiment according to FIG. 1 is characterized in that the actuation or closing direction and opening directions of the two switchable coupling devices are identical in each case; in FIG. 3, these are opposite to one another. The illustrated embodiments are further designed such that here is a guide of the two piston elements 4, 7 to each other, wherein the first piston member 4 may be performed on the second 7 or vice versa. The guide can take place in the region of an inner circumference forming partial area or of an outer circumference forming partial area. The actual design depends on the individual space conditions and the execution of the power transmission device 1. It is also essential, which type are the switchable clutches, in particular whether they are designed as a lock-up clutch or as corresponding turbine or impeller clutches. LIST OF REFERENCES

1 power transmission device

2 first switchable coupling device

3 actuating device first piston element

5 second switchable coupling device

6 adjusting device

7 second piston element

8 chamber

9 piston arrangement

10 interior

10.1 first compartment

10.2 second compartment

11 first connection

12 second connection

13 sealing device

14 outer circumference of the second piston element

15 inner circumference forming partial area

16 channel

17 channel

18 impeller clutch

19 lock-up clutch

20 hydrodynamic component

21 hydrodynamic speed / torque converter

22 wave

23 Device for damping vibrations

24 primary part

25 abutment

26 means for spring and / or damping coupling

27 spring unit

28 hub element

29 hub element

30 Axial and / or radial bearings

31 plate carrier 32 plate carrier

33 impeller shell

34 plate carrier

35 lead

36 Device for damping vibrations

37 primary part

38 Secondary section

39 means for spring and / or damping coupling

40 inner circumference

41 toothing element

42 toothing element

43 outer circumference

44 outer circumference

45 support shaft

46 stop

47 connection

48 groove

49 subchannel

50 central supply channel

51 connecting channel

52 sealing arrangement

53 turbine wheel clutch

53.1 first coupling part

53.2 second coupling part

55 first pressure chamber

56 housing

57 workspace

E entrance

A output

P impeller

T turbine wheel

L stator

Claims

claims 1. A power transmission device (1) for arrangement in a drive train between a prime mover and a transmission, comprising an input (E) and an output formed by a transmission input shaft (A) and two in one of a housing (56) and a first pressure chamber (55) forming the interior (10) arranged switchable coupling means (2, 4) - a first (2) and a second coupling means (4) - each having at least one acted upon by a pressure medium piston element (5, 7), characterized in that both Piston elements (5, 7) to form a second with respect to the interior (10) pressure and liquid-tight further pressure chamber (8) at the output (A) or a non-rotatably coupled thereto element (28) are guided and the individual pressure chambers (55, 8 ) via in the output (A) or the rotatably coupled element in the circumferential direction offset from each other and intersecting channels (16, 17) with pressure medium can be acted upon. 2. Power transmission device (1) according to claim 1, characterized in that the second switchable coupling device (5) is arranged on the first piston element (4) and the second piston element (7) on the first piston element (4) to form the pressure medium acted upon by pressure medium ( 8) is guided displaceably in the axial direction. 3. Power transmission device (1) according to claim 1 or 2, characterized in that in each case a plurality of the individual channels (16, 17) - first channels (16.1 to 16. n) and / or second channels (17.1 to 17. n) - are provided, which are viewed in the circumferential direction alternately arranged to each other. 4. Power transmission device (1) according to claim 3, characterized in that the arrangement of the channels (16, 17) takes place symmetrically in the circumferential direction. 5. Power transmission device (1) according to one of claims 1 to 4, characterized in that the alignment of the first pressure chamber (55) coupled to the first channels (16) takes place in the axial direction. 6. Power transmission device (1) according to one of claims 1 to 5, characterized in that the single second channel (17) in the radial direction of the rotation axis (R) toward the outer periphery of the output (A) or a non-rotatably connected thereto Element (28) extends. 7. Power transmission device (1) according to one of claims 1 to 6, characterized in that the first and second piston element (7, 4) form a piston assembly (9), wherein the two piston elements (7, 4) independently of one another in the axial Direction are displaced. 8. A power transmission device (1) according to any one of claims 1 to 7, characterized in that it comprises a hydrodynamic component (20) which has at least one impeller (P) and a turbine wheel (T). 9. A power transmission device (1) according to claim 8, characterized in that the hydrodynamic component (20) as a hydrodynamic speed / torque converter (21) is formed. 10. Power transmission device (1) according to one of claims 1 to 9, characterized in that the piston assembly (9) on the transmission input shaft (22) is guided and this in the region of the arrangement of the piston assembly (9) oriented in the radial direction projection under training a support surface area for the piston assembly (9). 11. Power transmission device (1) according to one of claims 1 to 9, characterized in that with the output (A) non-rotatably connected element (28) by a rotationally fixed to the turbine wheel (T) coupled hub member (28) is formed. 12. A power transmission device (1) according to claim 11, characterized in that the hub element (28) rotatably with a transmission input shaft (22) via the rotationally fixed connection of a power flow between input (E) and output (A) acting as an output part secondary part (25). a device (23) for damping vibrations is connected. 13. Power transmission device (1) according to one of claims 1 to 12, characterized in that the first and the second switchable coupling device (2, 5) are designed as frictional coupling device, in particular in lamellar construction, each switchable coupling device (2, 5) has at least a first coupling part (2.1, 5.1) and a second coupling part (2.2, 5.2), which are at least indirectly engageable with each other in operative connection. 14. Power transmission device (1) according to one of claims 1 to 13, characterized in that the first coupling device (2) by an impeller clutch (18) is formed. 15. Power transmission device (1) according to one of claims 1 to 13, characterized in that the first switchable coupling device (2) by a turbine wheel clutch (53) is formed. 16. Power transmission device (1) according to one of claims 1 to 15, characterized in that the second coupling device (5) by a bridging clutch (19) is formed. 17. Power transmission device (1) according to one of claims 1 to 16, characterized in that the actuating direction of the piston elements (47) in the closing direction of the individual coupling devices (2, 5) is the same. 18. Power transmission device (1) according to one of claims 1 to 16, characterized in that the actuating direction of the piston elements (4, 7) in the closing direction of the individual coupling devices (2, 5) is different.