EP2815154A1

EP2815154A1 - Actuator arrangement for a motor vehicle drive train

Info

Publication number: EP2815154A1
Application number: EP13704092.9A
Authority: EP
Inventors: Carsten Buender; Stefan Rothvoss
Original assignee: Getrag Getriebe und Zahnradfabrik Hermann Hagenmeyer GmbH and Co
Current assignee: Magna PT BV and Co KG
Priority date: 2012-02-14
Filing date: 2013-02-12
Publication date: 2014-12-24
Also published as: US20140346002A1; CN104334935A; EP2818766A2; CN104334935B; US9435384B2; DE102012003415A1; WO2013120814A1; EP2818766A3; EP2818766B1

Abstract

An actuator arrangement (30) for a motor vehicle drive train (10) which has at least one friction clutch (20, 24) for transmitting drive torque, in particular in the form of a starting clutch, as well as a gearbox (22, 26) having at least two gears (1, 2,...), which can be engaged and disengaged in a clutch arrangement (23, 25), having: a hydraulic circuit (36) that has a pump (38) driven by means of an electric motor (54); a clutch hydraulic cylinder (48) by means of which the friction clutch (20, 24) can be actuated; and a shift actuator device (55) actuating the clutch arrangement (23, 25). The shift actuator device (55) has a gear-shifting drum (56) which is or can be coupled to the electric motor (54) via a switch roller clutch device (60) in a manner such that the gear-shifting drum (56) can be set in motion by means of the electric motor (54) in order to actuate the clutch arrangement (23, 25).

Description

Actuator arrangement for a motor vehicle drive train

The present invention relates to an actuator assembly for a motor vehicle drive train having at least one friction clutch for transmitting drive torque, in particular in the form of a starting clutch, and a transmission having at least two gear ratios, which are switched on and interpretable by means of a clutch assembly, with a hydraulic circuit comprising a pump which is drivable by means of an electric motor, and which has a clutch hydraulic cylinder, by means of which the friction clutch is actuated, and with a switching actuator means for actuating the clutch assembly. Automated transmissions such as automated manual transmissions, dual-clutch transmissions, torque converter transmissions, etc. are known in the field of automotive powertrains. Automated transmissions are equipped both with regard to the clutch operation as well as the switching operation with suitable actuators to run these processes automated.

For actuating the friction clutch, it is known and preferred to use hydraulic actuators, in which the friction clutch is actuated by means of a clutch hydraulic cylinder. This allows a sensitive and fast control of the torque transmitted via the friction clutch, which is particularly important in dual-clutch transmissions of particular importance. Because here are two friction clutches for torque transfer of a power transmission branch on the other power transmission branch operated overlapping.

As a switching actuator device, it is also known to use hydraulic cylinders for actuating individual clutch packs such as synchronizers. The advantage here is that a uniform fluid source can be used for the friction clutch actuation and for the clutch actuation.

However, it is also known to electrically actuate the clutch assembly, for example by electromagnetic actuators or by electric motors. In the latter case, it is known to use so-called shift rollers for the actuation of clutches, which are driven by means of an electric motor.

It is also also known to provide clutch assemblies with switching shafts which are moved by means of a hydraulic cylinder in the switching direction, and which are moved by means of an electric motor in the direction of selection. For pressure control of a hydraulic fluid, it is known to generate a line pressure via a pump, which is kept constant by means of a pressure control valve. By means of further pressure control valves, the pressures of individual hydraulic cylinders are then adjusted. It is known to couple the pump to the internal combustion engine in the manner of a secondary drive.

However, it is also known to connect the pressure port of a pump directly to a hydraulic cylinder and to drive the pump by means of an electric motor. In this case, it is possible to control the pressure in the hydraulic cylinder by adjusting the rotational speed of the electric motor.

Against the above background, it is an object of the invention to provide an improved actuator assembly for a motor vehicle powertrain, which is particularly cost-effective and can be realized with a few components.

This object is achieved in the actuator assembly mentioned above in that the switching actuator comprises a switching drum which is so coupled or coupled to the electric motor via a shift drum coupling device, that the shift drum by means of the electric motor is set in rotation to to operate the clutch assembly.

The present invention is therefore fundamentally based on the fact that a friction clutch of an automated motor vehicle drive train is hydraulically actuated, wherein the associated hydraulic circuit has an electric motor driven pump. About the shift drum coupling device, it is possible to use the same electric motor also to rotate a shift drum, which serves to actuate the clutch assembly.

When using a shift drum for actuating the clutch assembly, it is advantageous that only a single drive for engaging and disengaging gears or multiple clutches is required. With In other words, a shift drum can also actuate a plurality of clutch packs (in particular synchronizers), for which purpose the shift drum preferably has a plurality of shift drum grooves. The shift drum can be used for example in an automated transmission for operating all the clutch packs of the transmission. However, it is alternatively also possible to provide a plurality of shift rollers, each actuate a subset of the clutch packs. In the latter case, it is possible that the shift drum coupling device couples the electric motor alternatively with different shift rollers. However, it is particularly preferred if each shift drum is assigned its own electric motor. Therefore, it is also possible that a separate electric motor is provided for a further shift drum, which is not used for the pump drive.

When applied to an automated manual transmission, which usually has only a single friction clutch in the form of a starting clutch, it is for example possible to connect the electric motor with a pump which generates a line pressure to actuate the friction clutch via a pressure accumulator is secured. Alternatively, it is also possible to connect the electric motor with a pump whose pressure port is connected directly to a clutch hydraulic cylinder. To this electric motor can then be coupled via the shift drum coupling means a shift drum or optionally a plurality of shift rollers. If only one shift drum can be coupled, a further shift drum can optionally be controlled via a separate electric motor.

Particular advantages, however, arise in motor vehicle powertrains, which have a dual-clutch transmission. Here are two friction clutches available, which preferably each own pump is associated with its own electric motor. Each of the two electric motors can be assigned a shift drum in this case via a shift drum coupling device. It is preferred if a shift drum, the gear stages of a sub-gear on and interpret, and the other shift drum, the gear ratios of the other sub-transmission. In In this case, it is advantageous that in each case that shift drum can be actuated by means of the associated electric motor, which is associated with the clutch actuation of the currently inactive subtransmission. Alternatively, however, it is also conceivable to distribute the gear stages in a different way to two (or even more) shift rollers.

Overall, a multiple use of electric motors can be achieved with the present invention, since in each case an electric motor can be used both to the pump drive and the shift drum drive. As a result, the actuator arrangement can be realized with a few components, in particular a few electric motors and a few electric pumps.

The electric motor can be positioned favorably, so that also package advantages can arise. Furthermore, there are also overall weight and cost advantages due to the small number of components used.

The problem is thus completely solved.

According to a particularly preferred embodiment, the electric motor is rigidly coupled to a drive shaft of the pump.

By this measure, the structure of the actuator assembly can be simplified as a whole. The shift drum coupling device can be coupled at any point to the output shaft of the electric motor or to the drive shaft of the pump.

[0020] It is particularly advantageous if the hydraulic circuit has a pressure reduction valve which, in a valve position, connects at least one pressure connection of the pump to a low pressure section. The pressure relief valve can thus be used to connect the pressure at a pressure port of the pump to the low pressure port, so as to avoid inadvertent operation of the friction clutch during operation of the shift drum. In other words, the pump may be actuated for the purpose of actuating the friction clutch when the shift drum coupling device has decoupled the shift drum from the electric motor. Conversely, when the shift drum coupling device is closed, the electric motor can drive the shift drum without simultaneously actuating the friction clutch or otherwise producing a working pressure on the side of the pressure port of the pump.

It is particularly preferred in this case if the pressure reduction valve in a valve position directly connects a pressure connection with a low pressure section, wherein the low pressure section may be a tank. In a second valve position, however, the pressure reduction valve may be closed, so that the low pressure section is separated from a high pressure section. The pressure reduction valve may preferably be designed as a directional control valve, preferably as a 2/2-way valve. The directional control valve can be actuated electrically or hydraulically.

According to a further preferred embodiment, the electric motor is coupled via a pump-coupling device with a drive shaft of the pump.

In this embodiment, an output shaft of the electric motor can thus be coupled via the pump coupling device with the drive shaft of the pump or decoupled therefrom, and further, the output shaft of the electric motor can be preferably coupled via the shift drum coupling device with the shift drum or decoupled therefrom ,

In this embodiment, it is possible to form the shift drum coupling device and the pump coupling device so that they only alternatively coupled to the output shaft of the electric motor. In this case, it may not be necessary to provide a pressure relief valve in the hydraulic circuit which connects at least one pressure port of the pump to a low pressure section in a valve position.

It is particularly advantageous if the shift drum coupling device and the pump-coupling device are integrated in a coupling device package.

Such a coupling device package may be similar to a clutch pack of a gearbox, so it may for example have a shift sleeve which is connectable to a coupling body of the shift drum coupling device or with a coupling body of the pump coupling device. The coupling device package can be designed in the manner of two clutches, which are designed as synchronized clutches. However, these clutches are preferably designed in each case as non-synchronized clutches, in particular as jaw clutches.

Overall, it is further preferred if the shift drum coupling device and / or a pump-coupling device is actuated by means of an electrically controllable Koppeleinrichtungsaktuators.

It is possible to actuate the shift drum coupling device and / or a pump-coupling device via a parent electrical or electronic control device.

According to an alternative embodiment it is provided that the shift drum coupling device and / or a pump coupling device is actuated by means of a hydraulic Koppeleinrichtungsaktuators. In this case, if necessary, resort to components in the already existing hydraulic circuit, so that there may be a saving of components.

In general, it is possible to use the actuator arrangement according to the invention, for example in automated manual transmissions or also in torque converter automatic transmissions. Further, it is possible to use the actuator assembly in hybrid powertrains, or even in purely electric drives in which a friction clutch and a transmission with at least two gear ratios are available.

Of particular preference, it is, however, if the motor vehicle drive train has a dual-clutch transmission with a first friction clutch and a second friction clutch, wherein the hydraulic circuit can be driven by a first electric motor first pump for the first friction clutch and a second electric motor driven by a second pump for the second friction clutch, wherein the shift actuator device comprises a first shift drum and a second shift drum, wherein the first shift drum via a first shift drum coupling means with the first electric motor is coupled and wherein the second shift drum via a second shift drum coupling means with the second Electric motor can be coupled.

In this embodiment, it is particularly advantageous that one of the two electric motors can be used, for example, to drive the associated pump so that the associated friction clutch is closed to transmit power through the associated power transmission line of the dual clutch transmission. In this case, the other electric motor can be connected via the associated shift drum coupling device with the associated shift drum to, for example, in an inactive partial transmission of the dual clutch gear ratios on and interpreted. In this embodiment, it is preferable if the hydraulic circuit has a cross-circuit portion which can connect at least one terminal of the second pump to a hydraulic first coupling actuator for actuating the first switching drum coupling device, and / or the at least one connection of the first pump a hydraulic second coupling actuator for operating the second shift drum coupling device can connect.

In this embodiment, for example, the pressure generated via the pump associated with the active power transmission branch of the dual clutch transmission may be used to actuate the hydraulic coupling actuator associated with the inactive power transmission path.

In the simplest case, a pressure connection of a pump can be connected to the hydraulic coupling device actuator, which is assigned to the other power transmission path.

It is preferred if the Koppeleinrichtungsaktuator has a spring by means of which the associated shift drum coupling device is pressed in an open state. The spring constant of this spring may preferably be designed such that it is deflected only in the case of a large force of the coupling device actuator. This force may correspond to a pressure at the pressure port of the pump of the other (active) power transmission path, which is so high that the friction clutch is suppressed, ie corresponding to a pressure which exceeds the closing pressure of the friction clutch. In this way it can be ensured that the Koppeleinrichtungsaktuator is only actuated when a targeted high pressure is set, which can be predetermined for example by an electrical control device. Alternatively or additionally, it is possible for the hydraulic coupling device actuator to be connected to a suction port of a pump (preferably to the suction port of the pump of the other power transmission path) in such a way that the coupling device actuator is supplied with fluid when the pump reverses its direction of rotation ,

In this variant, in a dual-clutch transmission, the hydraulic coupling actuator associated with the inactive power transmission path may be operated by the active power transmission path pump even when the friction clutch of the active power transmission path is not closed.

In other words, it can be achieved in this embodiment that gear ratios can also be engaged when none of the two power transmission paths is active, so for example in an idle position of the dual clutch transmission.

Overall, it is further preferred if the shift drum coupling device has at least one translation stage.

In this way, on the one hand the electric motor can be arranged spatially separated from the associated shift drum. Further, the electric motor can be coupled via a suitable translation with the shift drum.

The shift drum coupling device is preferably aligned concentrically with an output shaft of the electric motor and / or to a drive shaft of the associated pump.

Alternatively, however, it is also possible that the shift drum coupling device is integrated in the shift drum. Correspondingly, it is also possible that the electric motor is arranged coaxially with a drive shaft of the pump. Alternatively, it is also possible that the electric motor is arranged coaxially with the associated shift drum and is connected via a transmission stage with a drive shaft of the pump. The pump of the hydraulic circuit can be driven by means of the electric motor so that it generates a line pressure, from which is then derived or regulated by pressure control valves, a suitable pressure for actuating the friction clutch.

Of particular preference, however, it is when the pump has a pressure port which is directly connected to the clutch hydraulic cylinder.

In this case, the pressure in the clutch hydraulic cylinder is adjusted by a flow rate of the pump, which in turn is set via the rotational speed of the electric motor.

In this embodiment, it is advantageous that expensive proportional valves for actuating the friction clutch are not necessary. This not only has cost reasons, but it also simplifies the assembly, since the other components of the hydraulic circuit also preferably do not require proportional valves to the assembly generally increased demands are made in terms of cleanliness.

Furthermore, the above object is achieved by a motor vehicle drive train with an actuator assembly according to the invention, wherein the motor vehicle drive train preferably has a dual-clutch transmission of the type described above.

It is understood that the features mentioned above and those yet to be explained not only in the respectively indicated combination nation, but also in other combinations or in isolation, without departing from the scope of the present invention.

Embodiments of the invention are illustrated in the drawings and are explained in more detail in the following description. Show it:

Fig. 1 is a schematic representation of a first embodiment of a

Motor vehicle drive train with a first embodiment of an actuator assembly according to the invention;

FIG. 2 shows a schematic view of a further embodiment of an actuator arrangement according to the invention; FIG.

3 shows a schematic view of a further embodiment of an actuator arrangement according to the invention;

4 shows a schematic view of a further embodiment of an actuator arrangement according to the invention; and

Fig. 5 is a schematic representation of a shift drum with an integrated shift drum coupling device.

In Fig. 1, a motor vehicle drive train is shown in schematic form and generally designated 10.

The drive train 10 has a drive motor 12, which may be formed for example as an internal combustion engine. Furthermore, the motor vehicle drive train 10 has a dual-clutch transmission 14 whose input is connected to the drive motor 12 and whose output is connected to a differential 16. The differential 16 distributes drive power to two drive shafts 18L, 18R of the motor vehicle. The dual-clutch transmission 14 has two parallel power transmission lines. The first power transmission train includes a first friction clutch 20 and a first partial transmission 22. The first partial transmission 22 is used to set up odd forward gears \, 3, 5, ... and includes a clutch assembly 23, by means of these gear stages are switched on and ausgelegbar. The second power transmission line includes a second friction clutch 24 and a second partial transmission 26 associated with straight speed stages 2, 4, 6, .... The gear stages of the second partial transmission 26 can be switched on and disassembled by means of a clutch assembly 25. The clutch assemblies 23, 25 may have synchronization devices that can be actuated by shift sleeves, for example. The first friction clutch 20 and the second friction clutch 24 may each be designed as wet-running multi-plate clutches, but may also be designed as a dry friction clutches.

For automated actuation of the friction clutches 20, 24 and the clutch assemblies 23, 25, an actuator assembly 30 is provided. The actuator assembly 30 includes a first actuator portion 32 associated with the first power transmission line and a second actuator portion 34 associated with the second power transmission line.

The two actuator sections 32, 34 are constructed essentially identical, so that in the following only the first actuator section 32 will be described. Its elements are provided with the suffix "A", whereas the corresponding elements of the second actuator section 34 are provided with the suffix "B".

The hydraulic circuit 36A has a pump 38A. A suction port 40A of the pump 38A is connected to a low-pressure portion in the form of a tank 44. A pressure port 46A is directly connected to a clutch hydraulic cylinder 48A. The clutch hydraulic cylinder 48A serves to operate the first friction clutch 20 and has a spring 50A by means of which the clutch hydraulic cylinder 48A is brought into a position at which the first friction clutch 20 is opened.

The pump 38A has a drive shaft 52A which is rigidly connected to an unspecified output shaft of an electric motor 54A. The electric motor 54A is designed to be controllable with regard to its position and / or its rotational speed and provides a rotational speed ΠΑ at its motor output shaft.

To close the first friction clutch 20, the electric motor 54A is rotated, such that the pump 38A draws a volume flow from the low-pressure portion 44 via the suction port 40A and provides it at the pressure port 46A. This increases the pressure in the clutch hydraulic cylinder 48 so that it is deflected against the force of the spring 50A to close the friction clutch 20. By adjusting the rotational speed n _A , the degree of the pressure exerted by the clutch hydraulic cylinder 48 A on the first friction clutch 20 and / or the degree of the clutch travel can be adjusted, in particular regulated.

To open the first friction clutch 20 either the rotational speed n _{A is} reduced or even reversed in their direction, so that the clutch hydraulic cylinder 48 A is sucked empty. It goes without saying that, if appropriate, the pressure port 46A is to be connected via a valve to the low-pressure section 44, which will be discussed below.

The actuation of the second friction clutch 24 takes place in a corresponding manner via the second actuator section 34. For actuating the clutch assembly 23 of the first partial transmission 22, the first actuator section 32 includes a shift actuator device 55A. The switching actuator 55A has a shift drum 56A. The shift drum 56A may include one or more cam grooves (in FIG. 1, two cam grooves for operating two clutch packs, that is, four speed stages are shown in an advantageous manner).

Each of the cam grooves is preferably coupled to a shift sleeve of a clutch pack of the clutch assembly 23.

The shift drum 56 is rotatably mounted about an unspecified axis and coupled via a translation stage 58A with a shift drum coupling device 60. The shift drum coupling device 60 has a member non-rotatably connected to the output shaft of the electric motor 54A and a member rotatably supported with respect to the drive shaft of the electric motor 54A. The two members of the shift drum coupling 60A are either separate; In this case, the shift drum 56A is decoupled from the output shaft of the electric motor 54A. When the shift drum coupling device 60A is in the closed state, the output shaft of the electric motor 5A is coupled to the shift drum 56A via the transmission stage 58A, so that the shift drum 56A can be rotated by the electric motor 54A to actuate the clutch assembly 23.

In the present case, the shift drum coupling device 60 A is formed by a Stirnzahnkupplung 62 A. However, the shift drum coupling 60A may also be formed by a dog clutch, by a magnetic powder clutch, etc.

For operating the shift drum coupling device 60A, an electrical coupling actuator 64A is provided in the present case. This may for example include an electromagnet, by means of which the switching roller coupling device 60A is opened or closed. Preferably, the electrical coupling actuator 64A includes a biasing spring 65A by which the switching drum coupling 60A is biased to an open position.

In the present case, the output shaft of the electric motor 54A is rigidly connected to the drive shaft 52A of the pump 38A. Therefore, when the shift drum coupling 60A is closed to rotate the shift drum 56A, the pump 38A is also driven. To avoid accidentally actuating the associated first friction clutch 20, a pressure relief valve 66A is provided in the hydraulic circuit 36A. The pressure reduction valve 66A connects the pressure port 46A of the pump 38A to the low pressure section 44. In the first position shown in FIG. 1, the pressure port 46A is thereby separated from the low pressure section 44. By way of electromagnetic actuation, the pressure reduction valve 66A can be brought into a second valve position, in which the pressure port 46A is connected to the low pressure section 44.

The pressure reduction valve 66A is preferably brought into this position when the shift drum coupling device 60A is closed. In this case, when the shift drum 56A is driven by the electric motor 54A, the pump 38A conveys a flow through the suction port 40A to the pressure port 46A and thence via the pressure relief valve 66A into the low pressure section 44. In the opposite direction of rotation of the shift drum 56A, the pump delivers via the As a result, inadvertent operation of the first friction clutch 20 during the shift drum operation can be prevented. Further, to assist in quickly draining the clutch hydraulic cylinder 48A, the pressure relief valve 66A may connect the pressure port 46A to the low pressure portion 44. For controlling the actuator arrangement 30, a control device 70 is provided. The control device 70 serves, on the one hand, to control the electric motors 54A, 54B, it being possible, if appropriate, to provide corresponding power electronics for both motors as a whole or for each electric motor. Further, the controller 70 is connected to the electric couple actuators 64A, 64B to open or close the shift drum couple 60A, 60B. Further, the controller 70 is connected to the pressure relief valves 66A, 66B to bring them into one or the other valve position. Finally, the controller 70 is connected to a series of sensors, preferably including pressure sensors 72A, 72B, which measure the respective pressures in the pressure ports 46A, 46B and the clutch hydraulic cylinders 48A, 48B, respectively. Also, the controller 70 is preferably connected to rotational angle sensors 74A, 74B which detect the rotational angle of the shift rollers 56A, 56B.

In driving operation, power is transmitted in each case via one of the two power transmission branches or strands. This strand is then the active strand. In this case, the associated friction clutch is closed. During this phase, the shift drum coupling device 60 assigned to this active power transmission branch is preferably open. For example, when power is transmitted via the first power transmission line, the pump 38A is rotated to generate and track a volume flow that produces a corresponding closing pressure in the clutch hydraulic cylinder 48A. The first shift drum coupling device 60A is opened. During this phase, a gear stage in the sub-transmission of the inactive branch can be preselected, in the above example in the second sub-transmission 26. For this purpose, the pressure reduction valve 66B is brought into the second valve position, in which the pressure port 46B is connected to the low-pressure section 44 , Further, the second shift drum coupling device 60B is closed. Now, by turning the second electric motor 54B in the inactive partial transmission 26, a gear ratio can be preselected. In dual-clutch transmissions, transfer from one power transmission branch to the other power transmission branch takes place by overlapping actuation of the two friction clutches. During this phase, the switching drum couplers 60A, 60B are preferably opened respectively, and the pressure relief valves 66A, 66B are preferably in the first position where the respective pressure ports are separate from the low pressure section.

In the following Figs. 2 to 4 alternative embodiments of hydraulic circuits are explained, which generally correspond to the hydraulic circuit 36 of FIG. 1 in terms of structure and function. The same elements are therefore identified by the same reference numerals. The following section essentially explains the differences. 2, an actuator assembly 30 'is shown in which an output shaft 78A of the electric motor 54A is not rigidly coupled to the drive shaft 52A of the pump 38A. Rather, the output shaft 78A is coupled via a pump coupling device 82A to the drive shaft 52A or separable therefrom. As shown, the pump coupling device 82A can be integrated with the switching drum coupling device 60A in a coupling device package 80A. The same applies to the second actuator section.

The coupling device package 80A may be configured such that either the shift drum coupling device 60A or the pump coupling device 82A is closed, such that the output shaft 78A of the electric motor 54A is coupled to the shift drum 56A or to the drive shaft 52A of the pump 38A is. The coupling device package 80A can be constructed in the manner of a clutch pack, as it is also used in the partial transmissions 22, 26.

In this embodiment, it is not necessary to be able to connect the pressure port of the pump 38A to the low pressure section 44 via a pressure relief valve 66A. Rather, the actuator assembly 30 'may be implemented without such pressure relief valves 66. While the coupling devices 60 and 60, 82 are preferably actuated electromagnetically in the embodiments of FIGS. 1 and 2, in the following FIGS. 3 and 4 embodiments are explained in which these coupling devices are hydraulically actuated. In these embodiments, complex solenoid actuators are not required. Here, the general mode of operation of the actuator assembly 30 shown in FIG. 3 corresponds to that of the actuator assembly 30 'of FIG. 2, and the operation of the actuator assembly 30 "' of FIG. 4 corresponds to that of the actuator assembly 30 of FIG. 1.

In the embodiments 30 ", 30"'of FIGS. 3 and 4, instead of the electrical coupling actuators 64A, 64B, hydraulic coupling actuators 86A, 86B are provided. These each have a spring 88A by which the hydraulic couple actuators 86A, 86B are biased to a position. In the embodiment of Fig. 3, a coupling device package 80A is provided corresponding to that of Fig. 2, and the spring 88A biases the associated coupling actuator 86A to the position in which the electric motor 54A is connected to the drive shaft of the pump 38, ie the position in which the pump coupling device 82A is closed and the shift drum coupling device 60A is opened. The hydraulic circuits 36A, 36B of the actuator assembly 30 '' of Fig. 3 have a common crossover portion 90. This includes a first connection line 92A which connects a hydraulic cylinder of the hydraulic coupling actuator 86A to a port of the pump 38B, which may be the pressure port or the suction port In the present case, the pressure port and the suction port of the second pump 38B are connected to each other via a shuttle valve 94B, and the connection line 92A connects the shuttle valve 94B to the coupler actuator 86 A. Similarly, the second hydraulic coupler actuator 86B for the second coupler stack 80B is over Connecting line 92B of the cross-connecting portion 90 connected to a terminal of the first pump 38A, either with the pressure port or the suction port. In the present case, the second connecting line 92B with a corresponding shuttle valve 94A connecting the suction port and the pressure port of the first pump 38A together.

Accordingly, for example, the coupling device package 80A can be brought into the position in which the pump coupling device 82A is opened and the switching roller coupling device 60A closed by the second pump 38B is operated in the reverse direction, so that fluid through the pressure port 46B is sucked and passed through the suction port and the shuttle valve 94B in the first connection line 92A. This alternative mode of actuation is selected when the second friction clutch 24 is open. In contrast, when the second friction clutch 24 is closed, the pressure in the pressure port of the second pump 38B is greater than that in the associated suction port, so that the shuttle valve 94B switches. In this case, the pressure port 46B of the second pump 38B is connected to the first coupling actuator 86A via the first connection line 92A. In order to prevent inadvertent actuation of the coupling actuator 86A, the return spring 88A is designed so that it is not deflected during normal closing of the second friction clutch 24 and a corresponding pressure in the second pressure port 46B, ie the first coupling actuator 86A is not actuated becomes. However, the pressure in the pressure port 46B may be increased by increasing the rotational speed of the second electric motor 54B, so that the second friction clutch is over-pressurized. The pressure established thereby is sufficient to deflect the first coupling actuator 86A against the force of the spring 88A and thus to open the first pump coupling 82A and close the first switching drum coupling 60A, so that from this point on the switching drum 56A is actuated by means of the electric motor 54A can be twisted. Similarly, the second shift drum 56B may be actuated when the first pump 38A is operated in the opposite direction of rotation or at the first pressure port 46A creating a pressure that overruns the first friction clutch 20 and deflects the second linkage actuator 86B against the force of the spring 88B. FIG. 4 shows a further embodiment of an actuator arrangement 30 "', which generally corresponds in terms of structure and mode of operation to the actuator arrangement 30" of FIG. 3. The same elements are therefore identified by the same reference numerals. The following section essentially explains the differences.

In the actuator assembly 30 "', similar to the actuator assembly 30 of Fig. 1, no pump coupler 82 is provided, but an output shaft of the electric motor 54A is rigidly connected to a drive shaft of the associated pump 38A As a result, a pressure relief valve 66 'is provided between the pressure ports and the suction ports of the pumps 38. However, the pressure relief valves 66A', 66B 'of the actuator assembly 30 "' of Figure 4 are not actuated electromagnetically, but hydraulically. For this purpose, the first depressurizing valve 66A 'is connected to the first connecting line 92A, and the second depressurizing valve 66B' is connected to the second connecting line 92B. Accordingly, the closing of the switching drum couplers 60A, 60B are respectively synchronized with the displacement of the pressure relief valves 66A ', 66B' into the respective switching position in which the ports of the pumps are connected to the low pressure section.

Finally, Fig. 5 shows an alternative embodiment of a shift drum 56A ', into which is coaxially integrated a shift drum coupling device 60A', which can be connected directly or via a transmission stage 58A to the output shaft 78A of the electric motor. The shift drum coupling device 60A 'integrated in the shift drum 56A' can basically be constructed as explained above with reference to FIGS. 1 or 4. Optionally, a pump coupling 82 may be disposed between the output shaft 78A of the electric motor and the drive shaft of the associated pump, which is not shown in FIG.

Claims

claims

1. Actuator arrangement (30) for a motor vehicle drive train (10), the at least one friction clutch (20, 24) for transmitting drive torque, in particular in the form of a starting clutch, and a transmission (22, 26) with at least two gear stages (1, 2, ...), which by means of a clutch assembly (23, 25) on and be interpreted, with a hydraulic circuit (36) having a pump (38) which is drivable by means of an electric motor (54), and a clutch Hydraulic cylinder (48), by means of which the friction clutch (20, 24) is actuated, and with a switching actuator means (55) for actuating the clutch assembly (23, 25), characterized in that the switching actuator means (55) a A shift drum (56) which is coupled to the electric motor (54) via a shift drum coupling means (60) or coupled, that the shift drum (56) by means of the electric motor (54) is set in rotation to the Schaltkupplungsa arrangement (23, 25).

Second actuator assembly according to claim 1, characterized in that the electric motor (54) is rigidly coupled to a drive shaft (52) of the pump (38).

3. Actuator arrangement according to claim 2, characterized in that the hydraulic circuit (36) has a pressure reduction valve (66) which connects in a valve position at least one pressure port (46 A) of the pump (38) with a low pressure section (44).

4. actuator assembly according to claim 1, characterized in that the electric motor (54) via a pump-coupling device (82) with a drive shaft (52) of the pump (38) is coupled.

5. actuator assembly according to claim 4, characterized in that the switching roller coupling device (60) and the pump coupling device (82) in a coupling device package (80) are integrated.

6. Actuator arrangement according to one of claims 1 to 5, characterized in that the switching drum coupling device (60) and / or a pump coupling device (82) by means of an electrically controllable Koppeleinrich- tungsaktuators (64) can be actuated.

7. Actuator arrangement according to one of claims 1 to 5, characterized in that the switching drum coupling device (60) and / or a pump coupling device (82) by means of a hydraulic Koppeleinrichtungsaktua- sector (86) can be actuated.

8. Actuator arrangement according to one of claims 1 to 7, characterized in that the motor vehicle drive train (10) has a dual-clutch transmission (14) with a first friction clutch (20) and with a second friction clutch (24), wherein the hydraulic circuit (30) one of a first electric motor (54A) drivable first pump (38A) for the first friction clutch (20) and a second electric motor (54B) drivable second pump (38B) for the second friction clutch (24), wherein the switching actuator (55) a first shift drum (56A) and a second shift drum (56B), wherein the first shift drum (56A) via a first shift drum coupling means (60A) with the first electric motor (54A) is coupled and wherein the second shift drum (56B ) via a second shift drum coupling means (60B) with the second electric motor (54B) can be coupled.

9. actuator assembly according to claim 8, characterized in that the hydraulic circuit (30) has a cross-circuit portion (90) having at least one terminal (46 B, 40 B) of the second pump (38 B) with a hydraulic first Koppeleinrichtungsaktuator (86 A) for actuating the first Shift drum coupling device (60A), and / or the at least one port (46A, 40A) of the first pump (38A) with a hydraulic second coupling actuator (86B) for actuating the second shift drum coupling device (60B) connect.

10. Actuator arrangement according to one of claims 7 to 9, characterized in that the hydraulic Koppeleinrichtungsaktuator (86) with a suction port (40) of a pump (38) is connected, such that the Koppeleinrichtungsaktuator (86) upon reversal of direction of the pump ( 38) is supplied with fluid.

11. actuator assembly according to one of claims 1 to 10, characterized in that the shift drum coupling device (60) has at least one translation stage (58).

12. Actuator arrangement according to one of claims 1 to 11, characterized in that the shift drum coupling device (60Α ') in the shift drum (56A ¹ ) is integrated.

13. Actuator arrangement according to one of claims 1 to 11, characterized in that the pump (38) has a pressure connection (46) which is connected directly to the clutch hydraulic cylinder (48).

14. Motor vehicle drive train (10) with an actuator arrangement (30) according to one of claims 1 to 13.