DE102016115300B4 - Actuator arrangement for actuating an actuating unit in a motor vehicle and coupling arrangement with such an actuator arrangement - Google Patents

Abstract

An actuator assembly for actuating an actuator (36) in a motor vehicle, comprising: a hydraulic actuator (3) for acting on the actuator (36), a piston pump (7) having a piston (8) movably seated in a housing (9) in which hydraulic pressure is built up by oscillating movement of the piston (8) to pressurize the hydraulic actuating unit (3); an electrically controllable electromagnet (11) with an axially movable armature (12), the electromagnet (11) being designed around a To convert the current pulse into an axial movement of the armature (12), the armature (12) of the electromagnet (11) being fixedly connected to the piston (8) of the piston pump (7), and the piston (8) being energized by energizing the electromagnet (11 ) with at least three voltages (V1, V2, V3) can be converted into at least three positions, such that when a first voltage (V1) is applied to the electromagnet (11), the piston (8) assumes a first position (S1) When a second voltage (V2) is applied to the electromagnet (11), the piston (8) assumes a second position (S2) and a third position is applied when a third voltage (V3) is applied to the electromagnet (11) of the pistons (8) (S3) occupies.

Description

The invention relates to an actuator arrangement with for actuating an actuating unit in a motor vehicle and a coupling arrangement with such an actuator arrangement.

From the DE 10 2007 063 360 A1 a hydraulic arrangement for actuating an actuating unit in the drive train of a motor vehicle is known. The hydraulic assembly comprises a hydraulic actuator and a piston pump with a piston. The piston is movably seated in a housing, wherein hydraulic pressure is built up by oscillating movement of the piston for acting on the actuating unit. The piston pump is driven by a drive shaft of the motor vehicle, which has an eccentric, so that upon rotation of the shaft hydraulic pressure is built up.

From the DE 10 2004 042 208 A1 a piston pump for conveying a hydraulic fluid for a hydraulic control system of a motor vehicle is known. A linear electric motor is provided to drive a piston attached thereto via a piston rod. The piston rod is connected at its end opposite the linear motor with a valve control unit having a multi-way valve.

From the DE 10 2004 050 021 A1 a magnetic piston pump with a delivery piston is known, which is displaceable by cooperation of a magnet armature provided thereon with a solenoid between a first and a second end position. From the DE 10 2015 201 463 A1 For example, a method and a control device for operating a piston pump are known. The piston pump is driven by means of a coil of an electromagnet, wherein the piston is movable against a restoring force of a spring.

From the US 2007/0025861 A1 For example, a method of driving an electromagnetic pump is known. To move a piston, a pulsating current is used.

From the WO 2010/124668 A1 a method for operating a metering pump is known, comprising a reciprocating piston and an electrically energizable by applying a voltage drive unit.

From the US Pat. No. 6,386,842 B1 a fluid pump arrangement for a hydraulic brake system is known. The pump has a piston which is movably received in a housing. A piston rod connected to the piston extends axially out of the housing, and has an anchor portion at the end located outside the housing. An electrical coil is disposed coaxially with the piston rod on the housing. By applying the electric coil, a magnetic field is generated, which acts on the armature section in the direction of the housing, so that the piston is moved into the cylinder chamber.

From the DE 890 307 A is known an electromagnetic piston pump for pumping liquids. Pistons working in two separate, mirror-inverted cylinders are connected by a rod. The rod carries in the middle of an iron core, which is surrounded by two adjacent, alternately traversed by current coils.

The present invention has for its object to provide an actuator for actuating an actuating unit in a motor vehicle, in particular in a vehicle drive train, which is simple and compact and allows a simple and accurate control. Furthermore, a clutch arrangement for the drive train of a motor vehicle with such an actuator to be proposed.

A solution consists in an actuator for actuating an actuating unit in a motor vehicle according to claim 1.

An advantage of the actuator according to the invention is that it is simple and compact. Only one solenoid and one piston pump are required to produce a hydraulic actuating force. The solenoid is easily controlled by appropriate control of the input current. There are thus no further units, such as a relatively expensive electric motor, or mechanical transmission elements required, so that the present actuator is simple and has a small footprint. The actuator can be arranged spatially close to the actuator, which also has a favorable effect on the packaging and the weight. The hydraulic actuating unit may comprise, for example, a piston-cylinder unit, with a hydraulic chamber and a displaceable in the hydraulic chamber einitzendem actuating piston which acts on the actuating unit of the motor vehicle.

According to the armature of the electromagnet and the piston of the piston pump are rigidly connected together, and in particular designed in one piece. The electromagnet has, in addition to the armature, one or more coils which, upon application of an electric current, generate a magnetic field which acts on the armature to drive it move. When moving the armature of the associated pump piston is moved at the same time.

For controlling the electromagnet, an electronic control unit is provided, wherein the electromagnet is controlled by the control unit in particular by pulse width modulation of an electrical voltage. Pulse width modulation (PWM) is understood as a type of modulation in which a technical variable, for example an electrical voltage, changes between two values. In particular, at constant frequency, the duty cycle of a rectangular pulse can be modulated, that is to say the width of the individual pulses.

According to the invention, it is provided that the piston can be converted into at least three positions by energizing the electromagnet with at least three voltages such that, when a first voltage is applied to the electromagnet, the piston assumes a first position, when a second voltage is applied to the electromagnet, the piston becomes one assumes second position, and upon application of a third voltage to the electromagnet, the piston assumes a third position. By this configuration, two functions are realized in a simple manner by appropriate control of the electromagnet, namely conveying the hydraulic fluid for applying the actuating unit on the one hand and switching off or Drucklosschalten the system on the other.

The assignment of the piston positions to the voltages can be designed according to the requirements. It is particularly contemplated that the controllable solenoid and the piston pump cooperate such that upon pulsation of the current between two of the three voltages from the piston pump, hydraulic pressure is developed to pressurize the hydraulic actuator, and upon application of a third of the three voltages, the piston pump is depressurized. The assignment of the voltages of the electromagnet to the positions of the piston is arbitrary and can be designed individually according to the requirements of the actuator assembly. In an exemplary embodiment, the first and third voltages may correspond to the end positions of the piston and the second voltage to an intermediate position of the piston. Depending on the arrangement of the hydraulic line which connects the piston chamber with the hydraulic actuator, the piston pump by pulsating energizing the electromagnet between the first and second voltage (or between the second and third voltage), corresponding to an oscillating movement of the piston between an end position and the Intermediate position (or the intermediate position and the other end position) are actuated, while concerns the third voltage (or first voltage) would lead to de-pressure switching.

According to a first embodiment, the electromagnet can be designed in the form of a monostable electromagnet, such that the armature is acted upon when the electromagnet is energized in a first position. In de-energized state of the electromagnet, the armature can be moved by a spring in the opposite second position. In other words, the spring and the solenoid act on the piston with forces acting in opposite directions. Energizing the electromagnet moves the piston in a first direction, whereas the piston is urged in the opposite direction by the spring when the electromagnet is de-energized. In this embodiment, a single power supply is required, which may be, for example, a pulse width modulated DC power source, or else a pulse width modulated AC power source that may be combined with a permanent magnet.

In one embodiment of the actuator with a spring can be provided in particular that the piston is acted upon by the spring fluidly in the direction of the hydraulic actuator unit. In this way, the hydraulic pressure on the hydraulic actuator, or the force for the lifting movement, built by the spring. In contrast, the force for the return stroke is generated by the electromagnet, which counteracts the spring.

According to a second embodiment, the controllable electromagnet can be designed in the form of a bi-stable electromagnet, such that the armature can adopt two stable positions by appropriate control of the electromagnet. This can be achieved, in particular, by providing a first magnet, which acts on the armature in a first direction, and a second magnet, which acts on the armature in the opposite, second direction. At least one of the two magnets is designed in the form of an electrically controllable electromagnet, which builds up a magnetic field when energized. The other magnet may also be designed in the form of an electrically controllable electromagnet. In this case, two power supplies would be required for control, in particular a pulse width modulated DC power source. Alternatively, the second Manget can also be designed as a permanent magnet. In this case, a power supply is sufficient as described in connection with the first embodiment.

The electronic control unit is in particular designed to control the amplitude and the To control frequency of the electromagnet. The amplitude and the frequency of the electromagnet or of the armature determine the volume flow of the piston pump connected to the armature. That is, an electrical control of the amplitude and the frequency of the armature cause a corresponding control of the pump flow rate of the piston pump.

Furthermore, the electronic control unit is in particular designed to control the electric current for the electromagnet. In this case, the magnitude of the electric current of the electromagnet determines the force which acts on the armature, so that the pump pressure of the piston pump is controlled by controlling the electric current.

The piston pump has a pump chamber which is spatially limited by the piston and which is hydraulically connected to a reservoir via a first line and to the hydraulic actuating unit via a second line, wherein a check valve is arranged in at least one of the first and second lines. That is, there may be provided a check valve between the reservoir and the pump chamber and / or between the pump chamber and the hydraulic actuator.

Instead of a check valve on the inlet side, that is to say in the first line, an inlet control can also be provided at the inlet of the piston pump, in particular integrated into the piston pump. Such an inlet control may comprise a feed channel which opens into an annular groove in the piston chamber. The annular groove is axially covered in a first position of the piston, so that no hydraulic fluid from the hydraulic chamber can flow back into the reservoir. In a second position of the piston, the annular groove or the mouth of the feed channel is released, so that hydraulic fluid can be sucked from the reservoir into the hydraulic chamber.

According to one embodiment, at least one control valve may be provided in a connecting channel between the piston pump and the hydraulic chamber of the actuating unit. The control valve can be designed as a proportional valve, that is, as a continuous valve, or as a multi-way valve. The control valve regulates the hydraulic pressure and thus the travel of the actuating piston; It can also be called a control valve. Furthermore, at least one pressure limiting valve can be provided in the connecting channel. One or more check valves in the connection channels prevent unwanted reflux of the pumped hydraulic fluid. According to a preferred embodiment, a reservoir for the hydraulic fluid is provided, which is hydraulically connected to the piston pump. Between the reservoir and the pump, a further check valve is preferably provided.

After a possible concretization, at least one pressure sensor for detecting a signal representing the hydraulic pressure can be provided in the hydraulic system. The determined pressure can be used as an input signal for controlling the piston pump or the electromagnet, in order to control the hydraulic actuating unit in dependence on the applied pressure. The use of a sensor allows a particularly high positioning accuracy, in particular by means of a closed loop.

In a simple embodiment, a throttle may be provided in the hydraulic circuit, which may in particular be arranged between the hydraulic actuating unit and the reservoir. A control valve is not required in this embodiment.

According to a possible embodiment, a storage arrangement may be provided with a storage chamber, wherein the storage chamber is hydraulically connected to the at least one piston pump and can be filled by the latter with hydraulic fluid for generating a pre-pressure. The storage arrangement is particularly useful for supplying the hydraulic actuating unit with hydraulic fluid at peak loads, since this can be used to cover a demand exceeding the delivery volume of the piston pump. The storage arrangement preferably has pressure storage means, which are arranged in particular in the storage chamber. The pressure storage means may have various configurations, and include, for example, spring means or a gas reservoir.

The storage arrangement preferably comprises a pressure piston, which is movably seated in the storage chamber and which can be prestressed by conveying hydraulic fluid into the storage chamber in order to generate a pre-pressure. Preferably, the pressure piston is acted upon by a spring which biases the pressure piston against the pressure of the hydraulic fluid. Alternatively, a membrane may be provided which is seated in the storage chamber and forms a system boundary between the hydraulic fluid and a storage medium. The storage medium is gas, for example nitrogen.

According to a possible development, the power-actuated actuating unit has an actuating element for a shut-off system or for a transmission circuit in the drive train of a motor vehicle. For example, the actuating unit can be a clutch for connecting or disconnecting an optional drivable drive train, a clutch for switching a transmission circuit, or a lock-up clutch for blocking the compensating movement of a differential gear. Alternatively, the power actuator may also include actuators an active suspension control, in particular spring struts, or a stabilizer.

The object is further achieved by a hydraulically actuable clutch arrangement for the drive train of a motor vehicle, comprising: an actuator assembly which may be designed according to at least one of the above embodiments, and at least one friction clutch as an actuating unit, which is actuated by the actuator assembly, wherein the friction clutch a first coupling part connectable to a first drive part of the drive train, a second coupling part rotatable relative to the first coupling part and connectable to a second drive part of the drive train, and a pressure plate for drivingly connecting the first and second coupling parts.

With the hydraulically actuated clutch assembly the same advantages, ie simple and compact design with simple controllability, achieved as with the above-mentioned actuator assembly. In this respect, reference is made in this regard to the above description. The actuator assembly may have any of the above configurations.

By means of the actuator arrangement, the pressure plate of the friction clutch is acted upon, so that the friction clutch is actuated in particular in the closing direction. In this case, the hydraulic pressure determines the degree of torque transmission of the friction clutch between an open position in which no torque between the clutch input part and the clutch output part is transmitted, and a closed position in which the full torque between the clutch input part and the clutch output part is transmitted. By appropriate control of the electromagnet, any intermediate position of the clutch can be adjusted, in which only part of the full torque is transmitted as needed.

• 1 eine erfindungsgemäße Aktuatoranordnung in einer ersten Ausführungsform;
• 2 eine erfindungsgemäße Aktuatoranordnung in einer zweiten Ausführungsform;
• 3 eine erfindungsgemäße Aktuatoranordnung in einer dritten Ausführungsform;
• 4 einen Elektromagneten für eine erfindungsgemäße Aktuatoranordnung im Längsschnitt in einer Ausführungsform;
• 5 einen Elektromagneten für eine erfindungsgemäße Aktuatoranordnung im Längsschnitt in einer weiteren Ausführungsform;
• 6 einen Aktuator für eine erfindungsgemäße Aktuatoranordnung im Längsschnitt in einer Ausführungsform;
• 7 eine erfindungsgemäße Aktuatoranordnung in einer weiteren Ausführungsform;
• 8 ein Diagramm für einen möglichen Verlauf der Spannung und des Kolbenhubs über der Zeit; und
• 9 eine erfindungsgemäße Kupplungsanordnung mit einer erfindungsgemäßen Aktuatoranordnung nach Anspruch 1.

Preferred embodiments of the invention are illustrated in the drawings and will be described below with reference to the drawing figures. It shows:

• 1 an actuator assembly according to the invention in a first embodiment;
• 2 an actuator assembly according to the invention in a second embodiment;
• 3 an actuator assembly according to the invention in a third embodiment;
• 4 an electromagnet for an actuator assembly according to the invention in longitudinal section in one embodiment;
• 5 an electromagnet for an actuator assembly according to the invention in longitudinal section in a further embodiment;
• 6 an actuator for an actuator assembly according to the invention in longitudinal section in one embodiment;
• 7 an actuator assembly according to the invention in a further embodiment;
• 8th a diagram for a possible course of the voltage and the piston stroke over time; and
• 9 A coupling arrangement according to the invention with an actuator arrangement according to the invention according to claim 1.

The 1 to 8th will be described together below in terms of their similarities.

An actuator arrangement according to the invention 2 for actuating a power-operated actuating unit ( 36 ) or assembly of a motor vehicle (not shown) comprises at least one hydraulic actuator unit 3 with a hydraulic chamber 4 and one in the hydraulic chamber 4 slidably fitted actuating piston 5 , a piston pump 7 for generating a hydraulic pressure on the actuating piston 5 and an electrically controllable electromagnet 11 as a drive for the piston pump 7 ,

The adjusting piston 5 the hydraulic actuator 3 is by means of at least one ring seal 6 placed in a circumferential groove of the actuator piston 5 is seated, sealed against the cylinder wall and serves to actuate the actuating unit ( 36 ). The power-operated actuator ( 36 ), for example, a friction clutch, in particular a Reiblamellenkupplung be for the drive train of the motor vehicle, which in connection with 9 will be explained in more detail. For example, the friction clutch may be designed for switching on or disconnecting an optionally drivable drive train as required, or in the form of a blocking clutch for blocking the compensatory movement of a differential gear. Alternatively or in addition, the actuator arrangement can also be used for actuating actuators of an active chassis control, in particular struts, or a stabilizer.

The electromagnet 11 has an axially movable anchor 12 and at least one electrically switchable coil 13 . 13 ' on, which at Bestromen on the anchor 12 acts. Specifically, the electromagnet 11 designed to be a current pulse of the electric coil 13 . 13 ' in an axial movement of the armature 12 convert. When an electric current is applied, the at least one coil generates 13 . 13 ' a magnetic field, leaving the anchor 12 towards the coil 13 . 13 ' is attracted.

The control of the electromagnet 11 takes place electrically by means of an electronic control unit 31 , which is shown here only schematically. In particular, it is provided that the control takes place by pulse width modulation of the electrical voltage with which the electromagnet 11 is charged.

The piston pump 7 has a piston 8th on that in a pump housing 9 sits axially movable. The pump housing 9 forms a pump chamber 32 , It is envisaged that the anchor 12 of the electromagnet 11 firmly with the piston 8th the piston pump 7 connected is. Consequently, when moving the anchor 12 the associated pump piston 8th with moves, leaving the anchor 12 or the electromagnet 11 as a drive for the piston 8th serves. The piston 8th moves in the housing 9 back and forth, so in the pump chamber 32 a hydraulic pressure is built up.

The connection of the anchor 12 with the piston 8th can be at least one of positive, non-positive and / or cohesive. In particular, it is provided that the anchor 12 and the piston 8th rigidly connected so that they move together. In a manufacturing technology favorable design of the anchor 12 and the piston 8th be designed in one piece.

The pump chamber 32 is on the inlet side via a connecting channel 15 with a reservoir 14 hydraulically connected. On the outlet side, the pump chamber is via a connecting channel 16 with the operating unit 3 hydraulically connected. As further components are in the connecting channels 15 . 16 check valves 17 . 17 ' recognizable, which prevent a backflow of the hydraulic fluid, and a filter element 18 in the supply line 15 ,

Optional is a pressure sensor 21 provided for detecting a pressure signal which is the hydraulic pressure in the hydraulic line 16 or on the hydraulic actuator 3 represents. The determined pressure is used as input to control the electromagnet 11 used to the hydraulic actuator 3 to control depending on the applied pressure.

The operation of the actuator assembly 2 is such that by energizing the electromagnet 11 by means of the control unit 31 Hydraulic fluid from the reservoir 14 through the connection channels 15 . 16 in the hydraulic chamber 4 is promoted, so that the adjusting piston 5 for actuating the actuating unit ( 36 ) is moved axially. The volume flow of the hydraulic fluid can by appropriate energization of the electromagnet 11 by means of the control unit 31 be set. Because, the amplitude and the frequency of the anchor 12 are dependent on the amplitude and the frequency with which the coil 13 . 13 ' of the electromagnet 11 is energized. The armature or piston force is determined by the amount of electrical current with which the coil 13 . 13 ' is stimulated. Accordingly, by controlling the electric current, the pump pressure of the piston pump 7 to be controlled.

Hereinafter, the specifics of the various embodiments will be discussed.

In the embodiment according to 1 is in the drain line 20 , which can also be referred to as return, a throttle 27 be provided. About the throttle 27 can hydraulic fluid after disabling the piston pump 7 from the pressure room 4 in the reservoir 14 flow back so that the hydraulic pressure in the hydraulic actuator unit 3 decreases and the actuator ( 36 ) is opened.

2 shows an actuator assembly according to the invention 2 in an alternative embodiment, which in terms of their structure and operation of those 1 largely corresponds. In this respect, reference may be made to the above description, wherein like components are given the same reference numerals. The only difference is that in the present embodiment, a control valve 28 in the form of a multi-way valve (instead of a throttle) is provided. The multiway valve 28 is in the return line 20 arranged and designed in the form of a 2/2-way valve. In the valve position shown, the multi-way valve 28 closed so that upon actuation of the piston pump 7 a hydraulic pressure on the hydraulic actuator 3 is transmitted. Will the multiway valve 28 moved to the right, the hydraulic fluid from the actuator unit 3 drain to the reservoir, so that the actuator piston 5 hydraulic pressure is no longer applied and the power-operated actuating unit ( 36 ) of the motor vehicle is enabled accordingly.

3 shows an actuator assembly according to the invention 2 in a further embodiment, which in terms of their structure and operation of those 1 respectively 2 largely corresponds. In this respect, reference may be made to the above description, wherein the same components are provided with the same reference numerals as in the above figures.

In the present embodiment according to 3 is optionally a memory array 22 integrated as an accumulator in the hydraulic system. The memory arrangement 22 includes a storage chamber 23 passing through the connection channel 16 with the pump 7 on the one hand and the hydraulic chamber 4 on the other hand is hydraulically connected. Upon actuation of the electromagnet 11 promotes the piston pump 7 Hydraulic fluid in the storage chamber 23 against the force of elastic spring means 24 , This forms a pressure piston 25 in the impression cylinder 26 axially movable, a system boundary between the storage chamber 23 and the receiving space for the spring means 24 , Through the memory arrangement 22 a larger volume of hydraulic fluid is provided, if necessary for pressurizing the hydraulic actuator unit 3 can be used. In particular, peak loads with an increased demand for hydraulic pressure oil supply can be handled hereby.

Another difference from the above embodiments is that according to the present embodiment 3 a control valve 28 is provided in the form of a proportional valve. The proportional valve 28 is in the supply line 16 arranged. With a proportional valve 28 the hydraulic pressure or the flow can be set very precisely, so that a particularly sensitive control of the actuating force of the hydraulic actuator 3 is possible.

It is in 3 also with dashed line recognizable that a second hydraulic actuator unit 3 ' with an associated control valve 28 ' can be provided. This is in parallel arrangement to the first hydraulic actuator unit 3 ' arranged. Upon actuation of the piston pump 7 Both are actuators 3 . 3 ' subjected to hydraulic fluid. It is understood that the number is not limited to one or two, but that also more hydraulic actuation units can be connected. This also applies to the embodiments according to the 1 and 2 which may also have one, two or more hydraulic actuators.

4 shows a first embodiment of the electromagnet 11 designed in the form of a bi-stable electromagnet. That is, the electromagnet 11 is designed such that the anchor 12 can hold and hold two different positions stably. For this purpose, the electromagnet 11 two coils 13 . 13 ' on, of which a first coil 13 when energized the anchor 12 in a first direction R1 magnetically attracts or moves, and of which the second coil 13 ' when energized the anchor 12 in the opposite direction R2 magnetically attracts or moves. Both coils 13 . 13 ' are designed as electrically controllable coils by a control unit 31 . 31 ' be charged with electric current and build up a magnetic field when energized accordingly. In doing so, the coils become 13 . 13 ' controlled such that alternately the first or the second coil 13 . 13 ' be energized so that the anchor 12 is moved back and forth due to the magnetic forces acting on it. The control of the two coils 13 . 13 ' takes place in each case in particular by means of a pulse width modulated DC power source. In a modified embodiment, instead of one of the coils 13 . 13 ' , which build a magnetic field during energizing, also a permanent magnet can be used. In this case, a power supply or electrical control would suffice.

It can also be seen that the electromagnet 11 a feather 10 that has the anchor 12 or the associated piston rod 8th towards the pump chamber 32 applied. The feather 10 in particular, it serves to anchor 12 or the associated piston rod 8th in de-energized state of the electromagnet 11 occupies a defined position. In the present embodiment, this is a right-shifted end position of the anchor 12 , as in 4 shown. When the coil is energized 13 becomes the anchor 12 and with it the piston rod 8th moved to the left. It is understood that in a modified embodiment, the spring 10 also acting in the opposite direction, that is, to the left, can be installed. The feather 10 is here in the form of a coil spring, without being limited thereto.

The in 4 shown electromagnet 11 can be for anyone in the 1 to 3 shown embodiment of an actuator assembly according to the invention 2 be used.

5 shows a further embodiment of the electromagnet 11 , which in the present case is designed in the form of a monostable electromagnet. This means in particular that the anchor 12 in de-energized state of the electromagnet 11 or the coil 13 occupies a defined position. In the present case, the anchor 12 during energization of the electromagnet 11 in a first direction R1 acted upon, or moved to the first position (to the left in 5 ). This is done by the coil 13 creates a magnetic field that is the anchor 12 from the coil 13 acted upon. Accordingly, the material of the anchor is to be chosen so that it is repelled magnetically. In de-energized state of the electromagnet 11 becomes the anchor 12 from the spring 10 in the second direction R2 acted upon, or moved to the second position. In other words, the spring work 10 and the electromagnet 11 with in the opposite direction acting forces on the anchor 12 or the associated piston 8th one. In this embodiment, a single power supply 31 required, for example, a pulse width modulated DC power source.

In the present embodiment, the spring force acts in the direction of the pump chamber 32 , that is, the hydraulic pressure (stroke) is defined by the spring force. The return stroke of the piston 8th gets through the coil 13 which, when energized, produces a force acting in the opposite direction on the anchor 12 exercises. However, it is also a reverse arrangement conceivable, that is, that of the hydraulic pressure (stroke) through the coil 13 is accomplished during the return stroke by the spring 10 he follows.

The in 5 shown electromagnet 11 can be for anyone in the 1 to 3 shown embodiment of an actuator assembly according to the invention 2 be used.

6 shows the piston pump 7 in a modified embodiment. It can be seen that in the case 9 the piston pump 7 an inlet control 29 is provided. The inlet control 29 includes a feed channel 30 which is in an annular groove 31 in the inner wall of the pump chamber 32 empties. In a first position of the piston 8th - In the present case shifted to the right, as shown - is the annular groove 31 from the piston 8th axially covered, so that no hydraulic fluid from the pump chamber 32 in the reservoir 14 can flow back. In a second position of the piston 8th - Moved from the position shown to the left - is the annular groove 31 or the mouth of the feed channel 30 released, leaving hydraulic fluid from the reservoir 14 in the pump chamber 32 can flow in.

The electromagnet 11 the in 6 shown assembly according to one of the embodiments according to the 4 or 5 be designed. The electromagnet 11 and piston pump 7 The constructional unit formed can also be referred to as an actuator.

The 7 and 8th will be described together below. 7 shows an actuator assembly according to the invention 2 in a further embodiment, which in terms of their structure and operation of those according to the 1 to 3 largely corresponds. In this respect, reference may be made to the above description in terms of similarities, wherein like components are given the same reference numerals as in the above figures. 8th shows an example graphically the piston stroke S (Way) and the tension V (Current) at the electromagnet 11 over time t ,

A special feature of the present embodiment is that the piston 8th by appropriate energization of the electromagnet 11 with three voltages V1 . V2 . V3 in at least three positions S1 . S2 . S3 is convertible. When applying a first voltage V1 at the electromagnet 11 takes the piston 8th a first position S1 on, if a second voltage is applied V2 takes the piston 8th a second position S2 and in case of a third tension V3 takes the piston 8th a third position S3 one. By this configuration, the actuator assembly by appropriate driving of the electromagnet 11 in addition to the pumping function, realize a pressure-less switching of the system. In this case, the Drucklosschalt due to the fast reaction time of the electromagnet 11 and the rapid return of the hydraulic fluid take place particularly quickly, in particular faster than with a throttle (such as in 1 shown) or a valve (such as in 2 shown).

It can be seen that the spring 10 in the present embodiment so on the piston 7 acts to make a return stroke. The stroke for loading the pump chamber 32 with hydraulic pressure is generated by the electromagnet 11 causes. When applying a first voltage V1 becomes the anchor 12 by the magnetic force of the coil 13 in the direction of the pump chamber 32 applied. Accordingly, the one with the anchor 12 connected pistons 8th in one in the pump chamber 32 inserted first position S1 , When setting a second voltage V2 which is lower than the first voltage V1 , the piston becomes 8th from the spring 10 in the direction of the electromagnet 11 in a second position S2 applied, which lies between the maximum end positions. This second position S2 is in 7 drawn as a dashed line, which is the front side of the piston 8th should symbolize when the piston is in the second position S2 located. By oscillating movement of the piston 8th between the first and second stroke position S1 . S2 from the pump 7 Hydraulic fluid is discharged from the reservoir 14 to the operating unit 3 promoted. When the coil is switched off 13 that means tension V3 equal to zero, the piston becomes 8th from the spring 10 in the extended end position S3 acted upon, in which the pump chamber 32 is maximum. In this position, the end of the piston (dashed line at S3) has the mouth 33 the return line 34 and the mouth of the supply line 15 released, allowing the hydraulic fluid from the hydraulic chamber 4 the operating unit 3 over the pump chamber 32 in the reservoir 14 can drain off, leaving the actuator unit 3 quickly depressurized. This unpressurized state is in 8th represented by the line at time t3. Consequently, in the present embodiment, no additional control valve for the Control of the hydraulic pressure in the hydraulic chamber required. Rather, the pressure control and the pressure-less switching via the corresponding current supply of the electromagnet 11 ,

In 9 is a coupling arrangement according to the invention 35 with an actuator arrangement according to the invention 2 according to 1 shown. The coupling arrangement 35 includes a Reiblamellenkupplung 36 with a hydraulic actuator 3 according to the preceding figures. In a housing 37 is an input shaft 38 with a flange 39 around a rotation axis A rotatably mounted, wherein the input shaft, the clutch hub 40 the multi-plate clutch 36 wearing. The multi-plate clutch 36 further comprises a clutch basket 41 that with a hollow shaft 42 can be connected, in which an output shaft can be inserted. The alternately as inner disks 43 with the clutch hub 40 and as outer plates 44 with the clutch basket 41 connected clutch plates are supported on a flange 45 the clutch hub 40 and are from one in the clutch basket 41 sliding pressure plate 46 acted upon axially. printing plate 46 and clutch hub 40 are over a plate spring 48 supported axially against each other. The present designed as an annular piston pistons 5 the hydraulic actuator 3 acts via a thrust bearing 49 on the printing plate 46 when pressurized with hydraulic fluid. The interior 50 the multi-plate clutch 36 is filled with gear fluid.

About the feed line 16 and a housing bore 51 becomes the hydraulic chamber 4 , which is designed as an annular cylinder space, of the actuator assembly 2 Supplied hydraulic fluid. The ring piston 5 is about two sets of outer ring seals 6 and two sets of inner ring seals 6 ' opposite the oil-filled interior 50 the multi-plate clutch 36 sealed. At a wall portion of the hydraulic chamber 4 is the pressure sensor 21 via a housing bore 52 connected. In a print job by the actuator assembly 2 becomes the ring piston 5 in the direction of the pressure plate 46 shifted so that the multi-plate clutch 36 is closed. At a pressure relief of the actuator assembly 2 pushes the diaphragm spring 48 the pressure plate 46 back against the ring piston 5 , so that the multi-plate clutch 36 is relieved.

It is understood that the coupling arrangement shown 35 is only exemplary and that the actuator assembly according to the invention 2 also for any other clutch in the drive train of the motor vehicle or other actuators, such as for actuators of an active suspension control or a stabilizer is used. Furthermore, it is understood that any other actuator assembly 2 in accordance with the above in connection with the 2 to 8th described embodiments for the clutch assembly 35 can be used.

An advantage of the actuator assembly according to the invention 2 or a clutch assembly 36 with such an actuator arrangement 2 is that this is simple in that only one electromagnet 11 and a piston pump 7 are required to produce a hydraulic actuating force. The electromagnet 11 This can be done in a simple manner by appropriate modulation of the control current for the electromagnet 11 to be controlled.

LIST OF REFERENCE NUMBERS

2

actuator

3

Hydraulic actuator

4

hydraulic chamber

5

actuating piston

6

ring seal

7

piston pump

8th

piston

9

pump housing

10

spring means

11

electromagnet

12

anchor

13

Kitchen sink

14

reservoir

15

connecting channel

16

connecting channel

17, 17 '

check valve

18

filter element

20

Backflow channel

21

pressure sensor

22

memory array

23

storage chamber

24

spring means

25

pressure piston

26

pressure cylinder

27

throttle

28

control valve

29

intake control

30

connecting channel

31

ring groove

32

pump chamber

33

muzzle

34

Return line

35

clutch assembly

36

multi-plate clutch

37

casing

38

Belleville spring

39

flange

40

clutch

41

clutch basket

42

hollow shaft

43

inner disk

44

outer disk

45

flange

46

printing plate

48

Belleville spring

49

thrust

50

inner space

51

housing bore

52

housing bore

A

axis of rotation

S

Stroke / position

t

Time

V

tension

Claims (15)

Actuator arrangement for actuating an actuating unit (36) in a motor vehicle, comprising: a hydraulic actuator (3) for acting on the actuator (36); a piston pump (7) having a piston (8) which is movably seated in a housing (9), wherein hydraulic pressure is developed by oscillating movement of the piston (8) to pressurize the hydraulic actuator unit (3); an electrically controllable electromagnet (11) having an axially movable armature (12), the electromagnet (11) being configured to convert a current pulse into an axial movement of the armature (12), wherein the armature (12) of the electromagnet (11) is fixedly connected to the piston (8) of the piston pump (7), and wherein the piston (8) can be converted into at least three positions by energizing the electromagnet (11) with at least three voltages (V1, V2, V3) such that when a first voltage (V1) is applied to the electromagnet (11) the piston ( 8) occupies a first position (S1), when a second voltage (V2) is applied to the electromagnet (11) the piston (8) assumes a second position (S2), and when a third voltage (V3) is applied to the electromagnet (11) the piston (8) assumes a third position (S3). Actuator arrangement according to Claim 1 , characterized in that the controllable electromagnet (11) and the piston pump (7) cooperate such that upon pulsation of the current between two (V1, V2) of the three voltages (V1, V2, V3) of the piston pump (7) hydraulic Pressure for applying the hydraulic actuating unit (3) is constructed, and in the presence of a third (V3) of the three voltages, the piston pump (7) is depressurized. Actuator assembly according to one of Claims 1 or 2 , characterized in that a control unit (31) for controlling the electromagnet (11) is provided, wherein the electromagnet (11) from the control unit (31) by pulse width modulation of an electrical voltage (V) is controlled. Actuator assembly according to one of Claims 1 to 3 , characterized in that the controllable electromagnet (11) is designed in the form of a bi-stable electromagnet, which is designed such that the armature (12) in the de-energized state of the electromagnet (11) maintains its position. Actuator assembly according to one of Claims 1 to 3 , characterized in that the controllable electromagnet (11) is designed in the form of a mono-stable electromagnet, which is designed such that the armature (12) is energized in energizing the electromagnet (11) in a first position and in de-energized state of the Electromagnet (11) is acted upon by a spring (10) in a second position. Actuator assembly according to one of Claims 3 to 5 characterized in that the control unit (31) is arranged to control the amplitude and frequency of the armature (10) so as to control a pump volume flow of the piston pump (7) by controlling the amplitude and frequency, and / or in that the control unit (31) is designed to control the electric current for the electromagnet (11) so that a pump pressure of the piston pump (7) is controlled by controlling the electric current. Actuator assembly according to one of Claims 1 to 6 , characterized in that the piston pump (7) has a pump chamber (32) delimited by the piston (8), which via a first line (15) with a reservoir (14) and via a second line (16) with the hydraulic actuating unit (3) is hydraulically connected, at least in one of the first and second lines (15, 16) is arranged a check valve (17, 17 '). Actuator assembly according to one of Claims 1 to 7 , characterized in that at least one of a throttle (27) and a control valve (28), in particular in the form of a multi-way valve, is provided in a hydraulic line (20). Actuator assembly according to one of Claims 1 to 8th , characterized in that a pressure sensor (21) is provided for detecting a signal representing the hydraulic pressure in a hydraulic line (16). Actuator assembly according to one of Claims 1 to 9 , characterized in that an inlet control (29) is provided at the inlet of the piston pump (7), which in particular comprises a feed channel (30) and an annular groove (31) in the pump chamber (32). Actuator assembly according to one of Claims 1 to 10 , characterized in that the piston (8) by a spring (10) fluidly in the direction of the hydraulic actuating unit (3) is acted upon, so that by the spring (10), a hydraulic pressure on the hydraulic actuator unit (3) is constructed. Actuator assembly according to one of Claims 1 to 11 , characterized in that a storage arrangement (22) with a storage chamber (23) for storing hydraulic fluid is provided, wherein the storage chamber (23) is hydraulically connected to the piston pump (7) and can be filled by the latter with hydraulic fluid for generating a pre-pressure. Actuator arrangement according to Claim 12 , characterized in that the storage arrangement (22) has pressure storage means (24, 25) which are arranged in particular in the storage chamber (23). Actuator assembly according to one of Claims 1 to 13 , characterized in that the adjusting unit (36) has an actuating element for a shutdown system or for a transmission circuit in the drive train of a motor vehicle, in particular a clutch for connecting or disconnecting an optionally drivable drive train, a clutch for switching a transmission circuit, or a lock-up clutch of a differential gear. Hydraulically operable clutch assembly (35) for the powertrain of a motor vehicle, comprising: an actuator assembly (2) according to any one of Claims 1 to 14 ; and at least one friction clutch (36) as an actuator, which is actuated by the actuator assembly (2); the friction clutch (36) having a first coupling part (40) connectable to a first drive part of the drive train, a second coupling part (42) rotatable relative to the first coupling part (41) and connectable to a second drive part of the drive train, and a pressure plate (46) for drivingly connecting the first and second coupling parts (41, 42).

Images