DE102010033836A1 - Clutch actuator and method for its control - Google Patents

Abstract

The invention relates to a clutch actuator and a method for its control, which actuates a multiple clutch and this has one of the number of friction clutches corresponding actuator modules with separate control units and a higher-level control unit and controlled by these and acting on the friction clutches by means of a release mechanism electric motors. In order to counteract a blocking of the friction clutches, in particular forcibly closed friction clutches, downstream sub-drive trains in the event of a malfunction of an actuator module, the actuator modules are interconnected with a data line and by means of a respective control line to the superordinate control unit, which permits monitoring of the actuator modules and countermeasures. To minimize the number of lines with corresponding connectors, the function of controlling the actuator modules by the higher-level control unit and the function of a safety shutdown of an actuator module are represented by a single control line.

Description

The invention relates to a clutch actuator and a method for controlling it for a multiple clutch in a multiple clutch transmission with a corresponding number of sub-drive trains.

From the state of the art so-called dual-clutch or parallel-shift transmissions are known, which have two sub-drive trains, which can be coupled in each case by means of a friction clutch to an internal combustion engine. A circuit of such dual-clutch transmission takes place by the moment of the internal combustion engine is transferred in a so-called overlap of the friction clutches in slipping operation from one to the other part of the drivetrain in closed in both sub-drive trains, by the previously opened friction clutch is closed and the previously opened friction clutch is closed. During operation outside a circuit therefore always one of the two friction clutches must be opened to prevent blocking of the transmission and subsequently the drive wheels.

In the event of an unforeseen malfunction of a clutch actuator, care must therefore be taken that no blocking of the dual-clutch transmission occurs. For this purpose, for example, specially designed friction clutches are used, which are open in the relaxed state and are pressed by means of a non-self-locking clutch actuator. In the event of a malfunction, both actuator modules are cut off from the current supply so that both friction clutches open. If, as a result of malfunctions, an actuator module jams in the closed or slipping state of the associated friction clutch, the jamming of the transmission is avoided by the simultaneous opening of the other, functional friction clutch. The clutch actuator with the actuator modules must not be designed to be self-holding to a self-opening state in the de-energized state, whereby correspondingly large actuator forces must be provided, in particular electric motors with high performance and appropriate space must be used.

From the DE 10 2008 061 564 A1 For this purpose, a clutch actuator for actuating a multiple clutch with at least two friction clutches with two actuator modules, each with an electric motor and a driven by this disengagement, which acts on a respective friction clutch for their operation, and a higher-level control unit for controlling and powering the electric motors known in the the actuator modules are interconnected by means of a data line. In this case, a control of the actuator modules by means of a control line that connects both actuator modules and a higher-level control unit together. Furthermore, both actuator modules and the higher-level control unit are connected to each other by means of an overarching data bus (CAN bus). To form a safety shutdown, each output stage of an actuator module is additionally connected directly to the higher-level control unit. Such a circuit requires a complicated wiring with corresponding plug contacts.

It results in the task of proposing a clutch actuator and a method for its control, which manages with appropriate functionality with a smaller number of control lines and plug contacts.

The object is achieved by a clutch actuator for actuating a multiple clutch with at least two friction clutches consisting of at least two actuator modules, each with an electric motor and a disengagement mechanism driven by this, which acts on a respective friction clutch for their operation, and a higher-level control unit for activating and functional testing of the actuator modules and a higher-level control unit and actuator modules interconnecting data line and control lines between the parent control unit and each an actuator module for activation and safety shutdown of the actuator modules, which are guided for activation and safety shutdown via a single control line.

In an advantageous manner, the multiple clutch is a double clutch with two friction clutches, wherein in each case one actuator module of the clutch actuator actuates one of the two friction clutches. Each actuator module contains a control unit in which the signals for controlling the electric motor, for example, its commutation in the case of a brushless electronically commutated electric motor determined in this the rotational movement of the rotor detecting sensors such as Hall sensors and forwarded to the electric motor. Furthermore, in the control unit data, for example in the form of maps or mathematical functions, deposited, which deposits an assignment of the clutch to be transmitted via the friction clutch moment, which are constantly updated and adapted to the physical changes of the friction clutch and the release mechanism. In addition, a power electronics for Operation of the electric motor present in the control unit, so that the actuator module is independently capable of generating a necessary during a coupling process manipulated variable, output to the electric motor and monitor their implementation. One of the actuator modules or all may include functional software that may include higher level functions such as monitoring functions, communication with other onboard power supplies, and the like.

Advantageously, the operating states of the individual actuator modules are exchanged via the data line. In each of the actuator modules, for example, corresponding monitoring modules can be provided which check the signals output to the electric motor for their plausibility. If a malfunction of an actuator module results from this monitoring module, for example if the current supply to the electric motor is faulty or defective, the electric motor is defective and therefore does not set a calculated travel, the control unit itself has failed or the like, a corresponding information is sent to the other actuator modules , which - to avoid impending jamming of the transmission - the remaining friction clutches, in the case of a double clutch open the second friction clutch. Therefore, there is a control of the functional actuator modules depending on the operating state of a dysfunctional actuator module. In this case, if an actuator module continues to malfunction, an error signal can be transmitted via the data line to at least one further actuator module and at least one second actuator module can be operated in an emergency mode. In emergency mode, the exclusive function of the still functional actuator modules and the suppression of the dysfunctional actuator module can be initiated. In this case, the electric motor of the dysfunctional actuator module can be stopped immediately in its movement and the still functioning actuator modules cause the opening of their associated friction clutches, so that jamming of the transmission is excluded.

The actuator modules are advantageously connected in each case to a power supply of a vehicle electrical system and are put into operation when the vehicle is put into operation with a corresponding transmission and switched off again after the vehicle has been shut down. It has proven to be advantageous if the power supply permanently applied in the form of a supply line to the actuator modules and connected for example with an ignition switch, an ignition switch or other commissioning indicating switch control line is connected by means of a separate connector to the actuator modules, during the Operating the vehicle provides so much electrical energy that in the event of a cable break or a drop in the plug of the supply line for the power supply, at least the control unit with its low power requirements can be powered by the control line. The redundant supply of the actuator modules can also be done in other ways, for example by means of double plug and cable routing.

In a particularly advantageous manner, the proposed actuator modules for so-called forcibly opened friction clutches, which are closed in the relaxed state and pressed by means of an actuator module can be used. For this purpose, the actuator modules can be designed to be self-holding, so that such a friction clutch only requires very small actuation forces in the opened state. Due to the mutual monitoring of the actuator modules for malfunctions, no self-opening of both friction clutches is necessary in the event of a malfunction. Rather, the malfunction is detected in time by the or the remaining actuator module and the associated friction clutch open, so that the possibly no longer functioning and therefore torque transmitting friction clutch is the only moment transmitting friction clutch and therefore the transmission can not jam. By in contrast to a non-self-holding forcibly forced friction clutch lower holding forces of the open during driving friction clutch, the Aktorkräfte can be reduced and the associated electric motors are designed weaker. This can lead to a cost saving and smaller space requirement of the clutch actuator.

The two actuator modules are monitored by a higher-level control unit, wherein the two actuator modules are also equipped as so-called smart actuator modules equipped with their own processor units units. In this case, at least parts of a control and regulation of a friction clutch in the higher-level control unit and other parts of the control and regulation in the actuator units can be anchored as well as complete data processing for controlling and regulating the friction clutch in the higher-level control unit and in each case for an actuator module in the respective actuator module , In an advantageous manner, monitoring functions for an actuator module in the other actuator module are implemented. In this way, independent of any possibly caused for example by a processor defect investigations of a malfunction by the actuator modules can be mutually monitored or checked. In the same way, the results of the function monitoring of the two actuator modules are monitored by the higher-level control unit. It is particularly advantageous if to recognize a malfunction, the two monitoring units in the parent control unit and in the respective actuator module weighed against each other. Thus, for example, a malfunction can only be assessed as such if a malfunction for an affected actuator module is determined both in the actuator unit and in the higher-level control unit.

Furthermore, it may be advantageous if, in emergency operation, a signal is output to a control unit provided for the transmission control, which interprets a gear which may be engaged in one of the friction clutches with the partial drive train assigned to the faulty actuator module.

The activation of the actuator modules for the driving operation by the higher-level control unit takes place after determining the proper function of the actuator modules by transmitting a control signal to them. If a malfunction of one or both actuator modules occurs during operation, a safety shutdown of the affected actuator module takes place by outputting a shutdown signal from the higher-level control unit to the actuator module. At the same time, the other actuator module can be switched by means of the data line in an emergency operation. For easy transmission of the signals to the activation circuit and safety shutdown via a single control line per actuator module, this control line is maintained in an operating state of the vehicle at a "ON" level. This means that the control line is supplied with a voltage - a level - which is constantly monitored by the actuator modules. In this way, the corresponding actuator module is activated by switching the level. If the level "ON" is set to "OFF" as a result of a detected malfunction of the actuator module or due to a cable break or a connector drop on the actuator module, the actuator module initiates appropriate emergency measures, for example by the friction clutch in a secure final state, in which the friction clutch ever is opened, closed or held in its current position according to a given security concept, and / or the power amplifier is switched off immediately or subsequently.

If the driver initiates the decommissioning of the vehicle, the actuator modules can be controlled by the data line such as CAN bus in the end of the operating state, which is detected by switching off the ignition or other decommissioning significant signals of the vehicle from the parent control unit bring a predetermined end position. Thereafter, the level of the control line is set to "OFF", so that the output stages of the actuator modules are disabled. The actuator modules remain energized in a preferred manner, so that in the actuator module relevant data, such as adaptation parameters, can be stored and communication of the actuator module with the parent control unit is still possible.

According to the inventive idea, the reaching of the end position is transmitted via the data line to the higher-order control unit by means of an acknowledgment signal. After receiving the confirmation signal, the level of the control line is switched to "OFF". In the following Table 1 examples of the function of the clutch actuator in connection with the wiring of the actuator modules by means of a level on the single control line controlling the activation and the safety shutdown are shown. Table 1 shows various functions of the actuator module AM1, AM2, each of which controls a friction clutch K1, K2 of a dual clutch depending on the higher-level control unit OS. Function ÜS Function data line Level control line AM1 Level control line AM2 Function AM1 Function AM2 activation initialization ON ON Open K1 Open K2 operating condition data exchange ON ON K1 control K2 control Switch off operating status detected Control data to AM1, AM2 ON ON K1 in end position K2 in final position Confirmation signal end position received signal exchange OFF OFF Power amplifier disabled Power amplifier disabled Error AM1 Info: Error AM1 on AM2 OFF ON Power amplifier disabled Open K2 Error AM2 Info: Error AM2 on AM1 ON OFF Open K1 Power amplifier disabled Error ÜS initialization ON ON Open K1 Open K2 Table 1

The invention will be explained in more detail with reference to the embodiment shown in the single figure. This shows a schematic representation of a clutch actuator.

The figure shows schematically a clutch actuator 1 with two actuator modules 2 . 3 and a higher-level control unit 4 , The higher-level control unit 4 controls the actuator modules via the data line 5 , which may be part of a vehicle-wide data bus such as CAN bus or other bus systems such as LIN, MOST, FlexRAY or the like, for example. Independent of the data line 5 owns the clutch actuator 1 in each case a further single control line 6 to each actuator module 2 . 3 , on the one hand, the actuator modules 2 . 3 and on the other hand safety shutdowns of the actuator modules 2 . 3 be performed when from the parent control unit 4 a security risk or malfunction in one or both actuator modules 2 . 3 is recognized.

The actuator modules 2 . 3 each have a control part 7 with a logic part and corresponding peripherals in which the control and commutation of the electric motors 8th he follows. The control part 7 also captures and processes data from a sensor system for detecting the movement of the electric motors or their actuating kinematics for the associated clutch, such as friction clutch. Furthermore takes place in the control part 7 the processing of communication with the higher-level control unit 4 instead of. Each actuator module 2 . 3 has its own power supply 9 which is maintained regardless of the operating condition of the vehicle (for example, independent of KI15). The control part 7 controls the power amplifier 10 with preferably three phases via power electronics.

At the electric motor 8th it is an electronically commutated motor with Hall sensors whose signals are in the commutation unit of the control unit 7 be recorded. The commutation signals are sent to the power amplifier 10 transmitted, which is the electric motor 8th supplied with electrical energy. The control part 7 also includes a position controller, which depends on a functional software, in one of the two, in both actuator modules 2 . 3 or in the higher-level control unit 4 can be implemented, appropriate control commands for the affected, by the electric motors 8th by means of an actuating kinematics like release mechanism actuated friction clutch converts into electrical control signals and monitors a converted travel. In the embodiment shown, the actuator modules 2 . 3 the functional software and communicate via the data line 5 like CAN bus with other control units of the vehicle. The transmission of data of the functional software also takes place via the data line 5 ,

The control lines 6 fulfill the functions of activating the actuator modules 2 . 3 for example, at start-up of the vehicle and a safety shutdown at a malfunction according to Table 1, wherein the levels of the control lines 6 be switched to "ON" or "OFF" accordingly.

The actuator modules 2 . 3 monitor each other for malfunctions. This is done in each actuator module 2 . 3 multilevel monitoring, each of which performs a monitoring routine and, when properly functioning, the power amplifier 10 unlock. If a malfunction is detected, the power amplifier becomes 10 switched off and over the data line 5 the continuously updated operating status is switched from normal mode to error mode, for example by setting an error bit. The transmission of the operating state can qualitatively by sending an error message or quantitatively by the nature of the error is transmitted. Depending on the transmitted error message, the higher-level control unit reacts 4 with a setting of the level of the control line of the affected actuator module to "OFF" and the other, not affected by the malfunction actuator module is via the data line 5 controlled, for example by the electric motor 8th energized regulated or unregulated and thus the actuator associated with this module friction clutch is opened. To respond to a malfunction can after transmission of a malfunction in the other actuator module 2 . 3 accessed directly to the position controller and / or a routine for emergency operation of the functional actuator module can be started. In this way, for example, after laying out a possibly in the malfunctioning partial drive train inlaid gear the still functional part drive train can be operated automatically with traction interruption and limited gear selection. The control of the friction clutch can be done by means of the routine or with a running in the functional software routine.

The two actuator modules 2 . 3 be by means of a power supply 9 supplied with electrical energy from the electrical system of the vehicle. The control line 6 controls the activation and deactivation of the actuator modules 2 . 3 depending on a commissioning of the motor vehicle by setting the level to "ON". In the event of a power failure 9 For example, due to a cable break, a blown fuse or a drop in the connector detects the parent control unit via the data line 5 - In this case, by the lack of data communication with the affected actuator module 2 . 3 a malfunction and switches the level of the affected control line to "OFF".

LIST OF REFERENCE NUMBERS

1

clutch actuator

2

actuator module

3

actuator module

4

control unit

5

data line

6

control line

7

control part

8th

electric motor

9

power supply

10

final stage

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102008061564 A1 [0004]

Claims (7)

Coupling actuator ( 1 ) for a vehicle for actuating a multiple clutch with at least two friction clutches consisting of at least two actuator modules ( 2 . 3 ) each with an electric motor ( 8th ) and a driven by this disengagement mechanism, which acts on a respective friction clutch for their operation, and a higher-level control unit ( 4 ) for the activation and functional testing of the actuator modules ( 2 . 3 ) as well as a higher-level control unit ( 4 ) and the actuator modules interconnecting data line ( 5 ) and control lines ( 6 ) between the higher-level control unit ( 4 ) and in each case one actuator module ( 2 . 3 ) for activation and safety shutdown of the actuator modules ( 2 . 3 ), characterized in that signals for control and safety shutdown via a single control line ( 6 ) are guided. Coupling actuator ( 1 ) according to claim 1, characterized in that the control line ( 6 ) is maintained at a "ON" level in an operating condition of the vehicle. Coupling actuator ( 1 ) according to claim 2, characterized in that by the parent control unit ( 4 ) detected shutdown of the operating state, the actuator modules ( 2 . 3 ) bring the friction clutches in a predetermined end position. Coupling actuator ( 1 ) according to claim 3, characterized in that the actuator modules ( 2 . 3 ) when disconnected by means of the data line ( 5 ) to be controlled. Coupling actuator ( 1 ) according to claim 3 or 4, characterized in that reaching the end position by means of an acknowledgment signal via the data line ( 5 ) to the higher-level control unit ( 4 ) is transmitted. Coupling actuator ( 1 ) according to claim 5, characterized in that the higher-level control unit ( 4 ) after receiving the confirmation signal, the level of the control line ( 6 ) switches to "OFF". Coupling actuator ( 1 ) according to one of claims 2 to 6, characterized in that at one by the higher-level control unit ( 4 ) recognized malfunction of at least one actuator module ( 2 . 3 ) the higher-level control unit ( 4 ) the level of the control line of the affected actuator module ( 2 . 3 ) is set to "OFF".

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