Actuator with clutch actuator and integrated coolant pump function

Abstract

The invention relates to an actuating device (1) for a powertrain of a motor vehicle, comprising: an electromechanical clutch actuator (2) for actuating a clutch (3), the clutch actuator being electrically drivable; and an electrically drivable pump (4) for supplying a hydraulic medium, wherein the clutch actuator (2) and the pump (4) can be driven by a common electric motor (5).

Description

Technical Field

[0001] The invention relates to an actuating device for a drive train of a motor vehicle, in particular for a motor vehicle with a dedicated hybrid transmission (DHT transmission), having an electromechanical clutch actuator for actuating a clutch, the clutch actuator being electrically drivable, and having an electrically drivable pump for supplying a hydraulic medium. Background Art

[0002] Electric pump actuators (EPA) are already known from the prior art, in which an electric motor as a pump motor drives a pump for supplying a hydraulic medium, such as for supplying a coolant or for actuating a clutch. For example, WO 2012 / 113 368 A2 discloses a hydraulic device, in particular a hydraulic device for actuating a clutch, having a hydraulic working cylinder arranged close to the clutch, wherein the working cylinder is connected to a volume flow source via a hydraulic line, and wherein the volume flow of the volume flow source can be controlled by a control unit as a function of signals from a sensor associated with the hydraulic device, wherein the volume flow source is formed by a combination of an electric motor and a hydraulic pump arranged in a common housing.

[0003] Another document, such as WO 2015 / 149 778 A1, discloses a transmission control device for a fluid-operated transmission, the transmission comprising a plurality of gears which can be selected and shifted by means of a transmission actuator device and for fluid-operating two sub-clutches of a dual clutch. Here, the transmission control device comprises two reversible pump actuators, each of which is associated with one of the sub-clutches, and each of the reversible pump actuators has two ports, to which a fluid AND valve is connected, and the AND valve has a tank port as a third port, wherein the transmission actuator device is connected to the two reversible pump actuators via a fluid OR valve.

[0004] Furthermore, another document, such as WO 2015 / 117 612 A2, discloses a modular clutch actuator having a planetary gear rolling screw for actuating a clutch of a motor vehicle. The coolant pump is driven via a separate drive.

[0005] However, the prior art always has the disadvantage that two separate motors are always required to electromechanically drive the clutch actuator and the coolant pump, which is cost-intensive due to the provision of two motors, or the coolant circulation and the clutch actuation are driven electrohydraulically by means of a common pump, such as by an electric pump actuator (EPA), which is not possible for dry electromechanical actuators. Summary of the invention

[0006] The object of the present invention is therefore to avoid or at least reduce the disadvantages of the prior art. In particular, an operating device should be provided which enables the hydraulic medium supply and clutch actuation to be driven by a (dry) electromechanical actuator. In addition, the number of components of the operating device should be reduced.

[0007] The object is achieved in this device according to the invention in that the clutch actuator and the pump can be driven by a common electric motor. Thus, a common electric motor is used to drive the pump and the electromechanical actuator for actuating the clutch. In other words, the pump can also be driven for each revolution of the electric motor for actuating the clutch.

[0008] This has the advantage that no separate pump is required for supplying the hydraulic medium, in particular for driving the hydraulic medium circuit, so that the number of required components is reduced and the actuating device can be designed to be more compact and more cost-effective.

[0009] Advantageous embodiments are explained in detail below.

[0010] According to a preferred embodiment, the operating device can have a freewheel, which is arranged between the clutch actuator and the pump. That is to say, a freewheel is arranged between the electromechanical clutch actuator and the combination composed of the pump and the electric motor, and the freewheel can realize the clutch operation for the electric motor. By providing a freewheel, the electric motor cannot actively reset the clutch actuator, but this is not necessary due to the energy stored in the clutch for resetting, such as the energy stored by the return spring. Because the clutch operation usually does not transmit a pulling force, with the help of the pulling force, the clutch actuator can reset the clutch faster when the freewheel is not provided, so there is no dynamic disadvantage compared to the reset by the energy stored in the clutch, such as by the return spring. The clutch actuator can slow down the reset of the clutch in a targeted manner when necessary. According to the present invention, it is therefore possible to continue to rotate the electric motor when the final position of the clutch is reached, which is not possible without a freewheel. Therefore, the pump can be driven for any length of time by continuing to rotate the electric motor, up to the moment when the clutch must be re-operated.

[0011] In an advantageous development of this embodiment, the pump can be arranged between the freewheel and the electric motor or the electric motor can be arranged between the freewheel and the pump. That is to say, the pump can be arranged on the same side of the electric motor as the freewheel or on the opposite side. It is therefore decisive that the freewheel is not arranged between the electric motor and the pump.

[0012] It is also advantageous that the clutch actuator is designed as a linear actuator, by which the rotary motion of the electric motor can be converted into a linear motion for actuating the clutch by means of a rotary-linear transmission. Thus, the clutch can be actuated electromechanically in a simple manner.

[0013] The rotary-linear drive of the linear actuator is expediently designed as a ball screw drive. Ball screw drives have advantageously proven to be particularly robust and compact for converting a rotary motion into a linear motion.

[0014] It is also preferred that the rotary-linear transmission of the linear actuator is designed to be non-self-locking. Thus, automatic resetting of the clutch can be achieved, so that when the clutch actuator is decoupled from the rotary motion of the electric motor via the freewheel, the clutch can occupy its stable state.

[0015] It is also advantageous if the clutch actuator has a lever actuator. The lever actuator can be designed as an automatically opening lever actuator or an articulated lever actuator. Preferably, the lever actuator has a crossbar, the displacement of which by the linear movement of the linear actuator forces the clutch to be actuated. Therefore, the electric motor must be energized in order to keep the clutch actuated. In the absence of current, the clutch assumes its non-actuated / stable state. The arrangement according to the invention is therefore particularly advantageous in the case when the clutch must be actuated only for a relatively short period of time in order to prevent overheating of the components to be cooled.

[0016] According to a preferred embodiment, another freewheel can be provided between the pump and the drive shaft of the electric motor. Thus, the actuation dynamics of the clutch can be improved, because the pump no longer rotates together when the clutch is actuated.

[0017] In a development of the preferred embodiment, the electric motor can be driven in a first rotational direction to actuate the clutch and can be driven in a second rotational direction to drive the pump. The pump is thus driven only when the electric motor is reversed. This allows the use of an electric motor with a lower power, since the pump and the electromechanical clutch actuation do not have to be driven simultaneously.

[0018] In a preferred embodiment, the clutch is configured as a normally closed clutch, which can be operated to disconnect, or as a normally open clutch, which can be operated to close. That is to say, the clutch has exactly one stable state. Preferably, the clutch is configured as a normally closed clutch when the clutch must be closed for a larger time fraction than when disconnected. Preferably, the clutch is configured as a normally open clutch when the clutch must be disconnected for a larger time fraction than when closed. The clutch is configured so that it must be energized for operation and assumes its stable state in a currentless state. The stable state in the normally open clutch is the disconnected state. The stable state in the normally closed clutch is the closed state.

[0019] In other words, the present invention relates to an operating device, wherein a freewheel is provided between a clutch actuator for operating a clutch, which is configured as a screw, for example, and a motor-pump combination. Thus, the clutch can be operated via a motor. The motor-pump combination can be formed, for example, by a coolant pump and an electric motor, wherein the coolant pump is, for example, directly flange-connected to the electric motor. The pump can be arranged on the side of the motor facing the freewheel or on the side of the motor facing away from the freewheel. Therefore, the freewheel is not directly arranged between the electric motor and the pump. By arranging the freewheel in the operating device, the clutch actuator cannot be actively pulled back by the electric motor. The resetting of the clutch is usually carried out via a resetting spring of the clutch. That is to say, the energy for resetting is stored in the clutch and is available. The clutch actuator can slow down the resetting in a targeted manner when necessary.

[0020] By providing a freewheel, it is now possible to continue rotating the electric motor after reaching the end position of the clutch, which is not possible without the freewheel. Thus, by continuing to rotate the electric motor, the pump can be driven for any length of time until the clutch needs to be actuated again. This arrangement is particularly advantageous when the clutch must be actuated for only a relatively short period of time, because otherwise, i.e. during a long period of time for clutch actuation, overheating of the components to be cooled cannot be prevented. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The invention is explained below with the aid of the accompanying drawings. The accompanying drawings show:

[0022] Figure 1 A schematic diagram shows an operating device according to the present invention.

[0023] The drawings are only schematic and are only useful for understanding the invention. Identical elements are provided with the same reference numerals. DETAILED DESCRIPTION

[0024] Figure 1A schematic diagram of an actuating device 1 according to the invention for a powertrain of a motor vehicle is shown. The actuating device 1 has an electromechanical clutch actuator 2. The clutch actuator 2 is designed to actuate a clutch 3. The clutch actuator 2 can be driven electrically. The actuating device 1 has a pump 4 for supplying a hydraulic medium. The pump 4 can be driven electrically. According to the invention, the clutch actuator 2 and the pump 4 can be driven by a common electric motor 5.

[0025] A freewheel 6 is arranged between the clutch actuator 2 and the combination of the pump 4 and the electric motor 5. The freewheel 6 enables the clutch 3 to be actuated via the electric motor 5. In the embodiment shown, the pump 4 is arranged between the freewheel 6 and the electric motor 5. However, the electric motor 5 can also be arranged between the freewheel 6 and the pump 4. This means that the pump 4 is arranged on the side of the electric motor 5 facing the freewheel 6 or on the side of the electric motor 5 facing away from the freewheel 6, even if the latter case is not shown. The freewheel 6 for clutch actuation cannot be arranged between the pump 4 and the electric motor 5, because the freewheel 6 decouples the resetting of the clutch 3 from the operation of the electric motor 5 according to the invention.

[0026] In particular, the pump 4 is designed as a coolant pump 7. The coolant pump 7 can be flange-connected directly to the electric motor 5, for example. An additional freewheel can be provided between the drive shaft of the electric motor 5 and the pump 4, although this is not shown. As a result, the pump 4 can be connected to the electric motor 5 in such a way that the clutch actuator 2 can be driven in a first rotational direction of the electric motor 5 and the pump 4 can be driven in a second rotational direction of the electric motor 5. This means that the pump 4 is driven only when the clutch 3 is not actuated.

[0027] The clutch actuator 2 is designed as a linear actuator 8. Through the linear actuator 8, the rotary motion of the electric motor 5 can be converted into a linear motion for actuating the clutch 3 by means of a rotary-linear transmission. For example, the rotary-linear transmission is designed as a ball screw transmission. In particular, the rotary-linear transmission of the linear actuator 8 is designed to be non-self-locking, so that the clutch 3 can be reset.

[0028] The clutch actuator 2 has a rod actuator 9. The rod actuator 9 has an articulated actuator rod 10 and a crossbar 11. The linear movement of the rotary-linear drive moves the crossbar 11, so that the articulated actuator rod 10 moves about its rod joint 12 to actuate, and here disconnect, the clutch 3, which is designed as a normally open clutch 13 in the embodiment shown. The actuation bearing 14, i.e. the release bearing or the engagement bearing, is moved by the articulated actuator rod 10.

[0029] Description of Reference Numerals

[0030] 1 Control device

[0031] 2 Clutch actuator

[0032] 3 Clutch

[0033] 4 Pumps

[0034] 5. Electric Motor

[0035] 6 Freewheel

[0036] 7 Coolant pump

[0037] 8 Linear Actuators

[0038] 9-Rod Actuator

[0039] 10 Hinge actuator rod

[0040] 11 Crossbar

[0041] 12 rod joint

[0042] 13 Normally open clutch

[0043] 14 Manipulator bearing

Claims

1. An actuating device (1) for a powertrain of a motor vehicle, comprising: a dry electromechanical clutch actuator (2) for actuating a clutch (3), the clutch actuator being electrically drivable; and an electrically drivable pump (4) for supplying a hydraulic medium, It is characterized in that The clutch actuator (2) and the pump (4) are driven by a common electric motor (5); the actuating device (1) has a freewheel (6) which is arranged between the clutch actuator (2) and the combination of the pump (4) and the electric motor (5); the freewheel (6) decouples the resetting of the clutch (3) from the operation of the electric motor (5); the resetting of the clutch (3) is carried out via a resetting spring of the clutch (3); when the clutch actuator (2) is decoupled from the operation of the electric motor (5) via the freewheel (6), the clutch (3) assumes its stable state.

2. The operating device (1) according to claim 1, It is characterized in that The pump (4) is arranged between the free wheel (6) and the electric motor (5), or the electric motor (5) is arranged between the free wheel (6) and the pump (4).

3. The operating device (1) according to any one of claims 1 or 2, It is characterized in that The clutch actuator (2) is designed as a linear actuator (8), by means of which the rotational movement of the electric motor (5) can be converted into a linear movement for actuating the clutch (3) by means of a rotary-linear transmission.

4. The operating device (1) according to claim 3, It is characterized in that The rotary-linear transmission of the linear actuator (8) is designed as a ball screw transmission.

5. The operating device (1) according to claim 4, It is characterized in that The rotary-linear transmission of the linear actuator (8) is designed to be non-self-locking.

6. The operating device (1) according to claim 1 or 2, It is characterized in that The clutch actuator (2) has a rod actuator (9).

7. The operating device (1) according to claim 4 or 5, It is characterized in that The clutch actuator (2) has a rod actuator (9).

8. The operating device (1) according to claim 7, It is characterized in that The rod actuator (9) has an articulated actuator rod (10) and a crossbar (11), wherein the movement of the crossbar (11) is coupled to the linear movement of the rotary / linear transmission.

9. A manipulator (1) according to claim 1, 2, 4, 5 or 8, It is characterized in that A further free wheel is arranged between the pump (4) and the drive shaft of the electric motor (5).

10. The operating device (1) according to claim 5, It is characterized in that The electric motor (5) is drivable in a first rotational direction to actuate the clutch (3) and is drivable in a second rotational direction to drive the pump (4).

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