DE102022101840A1 - Electromechanical actuation actuator and method for operating an electromechanical actuation actuator - Google Patents

Abstract

The invention relates to an electromechanical actuating actuator (11) with an electric motor (12) which is drivingly connected to a pump (9) which is used to supply cooling and/or lubrication (4) with a suitable medium, and with an actuating element (10) which can be displaced translationally along an actuating path (33) with the aid of the electromechanical actuating actuator (11).
In order to reduce the cost of manufacturing and/or selling the electromechanical actuating actuator (11), the drive connection between the electromechanical actuating actuator (11) and the pump (9) includes an idle spring device (50) which, before torque is transmitted via the drive connection, allows a defined number of relative rotations in opposite directions of rotation without a torque driving the pump (9) being transmitted via the drive connection.

Description

The invention relates to an electromechanical actuation actuator with an electric motor which is drivingly connected to a pump which is used to supply cooling and/or lubrication with a suitable medium, and with an actuation element which can be displaced translationally along an actuation path with the aid of the electromechanical actuation actuator. The invention also relates to a method for operating such an electromechanical actuating actuator in a hydraulic system.

From the German Offenlegungsschrift DE 10 2018 112 213 A1 a transmission actuator with at least one electric motor is known, which drives a pump, the electric motor causing a linear displacement of a selector shaft by means of a transmission converting a rotary drive of a rotor of the electric motor into a linear movement, wherein a drive shaft of the pump is switched into the transmission and is rotationally driven by the latter when the selector shaft is shifted into a central position along the shift gates, or preferably by another electric motor. From the German Offenlegungsschrift DE 10 2018 114 902 A1 discloses a spindle actuator with a spindle drive, which includes a spindle nut that can be rotated by an electric motor and that interacts with a spindle rod in such a way that the spindle rod performs a linear movement when the spindle nut rotates.

The object of the invention is to reduce the costs for producing and/or operating an electromechanical actuating actuator according to the preamble of patent claim 1 .

The object is achieved with an electromechanical actuating actuator with an electric motor, which is drivingly connected to a pump, which is used to supply cooling and/or lubrication with a suitable medium, and with an actuating element, which can be displaced translationally along an actuating path with the aid of the electromechanical actuating actuator, in that the driving connection between the electromechanical actuating actuator and the pump comprises an idle spring device, which defines a idling spring device before torque is transmitted via the driving connection Allows a number of relative rotations in opposite directions of rotation without a torque driving the pump being transmitted via the drive connection. The electromechanical actuating actuator is designed, for example, as a spindle actuator. The pump is, for example, a simple pump that delivers a suitable medium for cooling and/or lubricating purposes in one delivery direction. However, the pump can also be designed as a reversible pump. The medium is, for example, a hydraulic medium such as oil. However, the medium can also be water. Then the pump can be designed as a water pump. The electromechanical actuation actuator is advantageously combined with an engagement and disengagement device. The engagement and disengagement device ensures that the driving connection between the electromechanical actuating actuator and the pump is maintained even when the actuating element reaches the end of the actuating path. To travel through the actuation path, the electromechanical actuation actuator requires a certain number of revolutions, for example ten revolutions. After that, it is spouted. After disengagement, only the pump is driven. The idling spring device advantageously serves to ensure that the pump is not driven by the electromechanical actuating actuator while the actuating element is displaced in a translatory manner with the aid of the electromechanical actuating actuator. This is particularly advantageous when a lot of energy is needed to drive the pump, for example at low temperatures. Among other things, the no-load spring device provides the advantage that the entire energy of the electromechanical actuating actuator can be used for the translatory displacement of the actuating element.

The electromechanical actuating actuator is preferably designed as a spindle actuator with a spindle nut/spindle rod that can be rotated by an electric motor and which interacts with a spindle rod/spindle nut in such a way that the spindle rod/spindle nut performs a linear movement along the actuating path when the spindle nut/spindle rod is rotated. The spindle actuator is advantageously combined with an engagement and disengagement device, which is designed and arranged in such a way that the spindle rod/spindle nut disengages at one end of the actuation path, with the spindle rod/spindle nut engaging again after the spindle nut/spindle rod has reversed its direction of rotation, with the disengagement and engagement device ensuring that the drive connection between the electric motor and the pump is maintained even when the spindle rod/spindle nut reaches one end of the actuation path. After disengagement, further rotation of the spindle nut/spindle rod no longer leads to a linear movement of the spindle rod/spindle nut. If the spindle nut/spindle rod is turned further, the electric motor drive is only used to drive the pump. The engagement and disengagement device can only be effective at one end of the actuation path. Particularly advantageous However, the engagement and disengagement device is effective at both opposite ends of the actuation path. Starting from an end position when a rotor of the electric motor rotates, the actuating element can first be displaced axially by the spindle rod or the spindle nut. As soon as the end of the actuation path, which is also referred to as the end position, is reached, the spindle nut and the spindle rod disengage. When the rotor continues to rotate, only the pump is then driven. If the direction of rotation is reversed, the process takes place in the opposite direction, so that a pump function can also be displayed in both end positions. During actuation, the pump does not run due to the function of the idling device. However, since actuation with the spindle actuator requires only a few turns, there is no risk of unwanted or damaging cooling and/or lubrication. The pump can be designed as a simple pump that delivers in one direction only. This is sufficient, for example, when a parking lock is actuated, since the cooling/lubrication, for example of a transmission, power electronics, a traction machine or the like, is primarily required when the parking lock is in an open state. However, the pump can advantageously also be designed as a reversible pump, which delivers hydraulic medium in two opposite delivery directions. For example, after-cooling can be implemented when the vehicle is parked. The medium is preferably a hydraulic medium, which is also referred to as hydraulic oil. However, the medium can also be water. Analogously, the pump can be a water pump.

A preferred exemplary embodiment of the electromechanical actuating actuator is characterized in that the pump is designed as a reversible pump, which includes two delivery connections, through which a hydraulic medium can be delivered from a tank via a valve arrangement, which only includes passive valves, in opposite delivery directions in order to supply the cooling and/or lubrication with hydraulic medium. The passive valves are advantageously designed as check valves. Among other things, this provides the advantage that an active valve can be dispensed with.

Another preferred exemplary embodiment of the electromechanical actuating actuator is characterized in that the engagement and disengagement device is combined with an overtravel mechanism that includes at least one overtravel spring that ensures correct engagement again after disengagement at the end of the actuation path after the spindle nut/spindle rod has reversed its direction of rotation. This ensures proper operation of the multifunction unit in a simple manner.

Another preferred exemplary embodiment of the electromechanical actuation actuator is characterized in that the overtravel mechanism is integrated into the spindle actuator. In this way, the overtravel mechanism can advantageously be accommodated in a housing of the spindle actuator in a protected manner together with the off and on-gear device.

Another preferred exemplary embodiment of the electromechanical actuating actuator is characterized in that the overtravel mechanism is integrated into the actuating element. This simplifies the use of a conventional spindle actuator, for example.

A further preferred exemplary embodiment of the electromechanical actuating actuator is characterized in that the idling spring device comprises at least two idling springs which act in opposite directions in the event of a relative rotation. The two idler springs are designed and arranged in such a way that when there is a relative rotation, one idler spring unwinds while the other idler spring winds up. As soon as an idler spring is completely wound up or wound up, torque for driving the pump is transmitted via this idler spring, which is then, for example, blocked, when it is rotated further, while the other idler spring simply rotates as well. This process is repeatedly reversible. In this way, it is achieved in a simple manner that the actuating element can be displaced in a translatory manner along its actuating path with the aid of the electromechanical actuating actuator, without the pump being driven at the same time.

A further preferred exemplary embodiment of the electromechanical actuating actuator is characterized in that the idling springs are designed as spiral springs wound in opposite directions. The coil springs can also be referred to as drive springs or torsion springs, with the elastic properties of the coil springs not being used in the claimed application, in contrast to conventional applications, to transmit torque. Torque is only transmitted via one of the idling springs when it is fully wound up or is blocking.

Another preferred exemplary embodiment of the electromechanical actuating actuator is characterized in that the idling springs are arranged in an axially adjacent manner. The term axial refers to an axis of rotation of the electromechanical rule actuating actuator or the pump, in particular a spindle or spindle nut of the designed as a spindle actuator electromechanical actuating actuator and / or a pump shaft of the pump. Axial means towards or parallel to this axis of rotation. Due to the axially adjacent arrangement, radial installation space can be saved.

Another preferred exemplary embodiment of the electromechanical actuating actuator is characterized in that the idle springs are each connected non-rotatably with a radially outer/inner end to a hub-like rotor body of the electric motor and are non-rotatably connected with a radially inner/outer end to a pump shaft. This results in a relatively simple construction of the idling spring device. One of the idler springs is wound onto the pump shaft during operation of the idler spring device, while the other idler spring is wound into the hub-like rotor body.

A further preferred exemplary embodiment of the electromechanical actuating actuator is characterized in that a first no-load spring is wound into the hub-like rotor body with a defined number of no-load windings. The number of no-load windings preferably corresponds essentially to the number of rotations required by the electromechanical actuating actuator in order to translate the actuating element along its actuating path. The number of no-load windings is particularly advantageously slightly larger than the number of revolutions required of the electromechanical actuating actuator to move the actuating element. It is thus ensured in a simple manner that the pump is only driven when the movement of the actuating element has ended.

Another preferred exemplary embodiment of the electromechanical actuating actuator is characterized in that a second no-load spring is wound onto the pump shaft with a defined number of no-load windings. The number of these no-load windings advantageously corresponds to the previously described number of no-load windings with which the first no-load spring is wound in the hub-like rotor body. This simplifies the manufacture and assembly of the idling springs.

Another preferred exemplary embodiment of the electromechanical actuating actuator is characterized in that the idle springs are arranged and designed in such a way that the hub-like rotor body is rotated with little torque relative to the pump shaft until a spring strip of the second idle spring is completely wound up on the pump shaft, before a torque is transmitted to the pump shaft from the hub-like rotor body via the second idle spring. Low-torque means that in this case it is virtually torque-free. The hub-like rotor body is largely non-rotatably connected to the pump shaft via the wound torsion spring. The process described can be reversed any number of times. In the opposite case, the hub-like rotor body is rotated relative to the pump shaft in the opposite direction of rotation with little torque until a spring strip of the first idle spring is completely wrapped in the hub-like rotor body, before a torque is transmitted from the hub-like rotor body to the pump shaft via the first idle spring. It is only necessary to ensure that a sufficiently large counter-torque is always made available on the pump shaft in order to ensure that the idling springs are fully wound up or unwound when the direction of rotation is reversed. This ensures that the idle springs are in the correct condition as soon as the counter-torque caused by the pump increases, for example at low temperatures at the pump.

The invention also relates to an idling spring device, in particular an idling spring, for an electromechanical actuating actuator described above. The idle spring device, in particular the idle spring, can be traded separately.

In a method for operating an above-described electromechanical actuating actuator in a hydraulic system, the above-mentioned object is alternatively or additionally achieved in that a drive of the electromechanical actuating actuator can freely perform a specific number of revolutions relative to an output with the pump until one of the idle springs is wound up/unwound. In this case, free means low-torque, i.e. virtually torque-free.

• 1 eine schematische Längsschnittdarstellung eines elektromechanischen Betätigungsaktors mit einem Spindelaktor und mit einer Pumpe zur Versorgung einer Kühlung und/oder Schmierung mit einem geeigneten Medium gemäß einem ersten Ausführungsbeispiel;
• 2 einen vergrößerten Ausschnitt aus 1 mit einer Leerlauffedereinrichtung, die antriebsmäßig zwischen dem elektromechanischen Betätigungsaktor und der Pumpe angeordnet ist; und
• 3 eine perspektivische Darstellung der Leerlauffedereinrichtung aus 2.

Further advantages, features and details of the invention result from the following description, in which various exemplary embodiments are described in detail with reference to the drawing. Show it:

• 1 a schematic longitudinal sectional view of an electromechanical actuating actuator with a spindle actuator and with a pump for supplying cooling and/or lubrication with a suitable medium according to a first exemplary embodiment;
• 2 an enlarged section 1 with an idle spring device, the drivingly between the electromechanical actuating actuator and the pump is arranged; and
• 3 a perspective view of the idling spring device 2 .

In 1 an electromechanical actuating actuator 11 with an electric motor 12 is shown in different views. The electric motor 12 includes a stator 13 in which a rotor 14 is rotatably arranged with the aid of a bearing device 15 .

The electromechanical actuating actuator 11 is designed as a spindle actuator 30 with a spindle nut 31 and a spindle rod 32 . The spindle nut 31 is connected to the rotor 14 of the electric motor 12 in a torque-proof manner.

The spindle rod 32 is equipped with an anti-twist device. It is thus achieved that the spindle rod 32 is displaced in the axial direction along an actuation path 33 when the spindle nut 31 is rotated relative to the spindle rod 32 . The structure and function of such spindle actuators 30 are known per se.

The rotor 14 of the electric motor 12 is drivingly connected to a pump 9, which is used to supply cooling and/or lubrication 4 with a suitable medium. The medium is preferably a hydraulic medium, such as oil or water, which is sucked in from a tank 6 with the aid of the pump 9 via a filter device 7 which can be designed as a suction filter. The cooling and/or lubrication 4 serves to cool and/or lubricate a transmission 5 indicated by way of example.

The pump 9 is designed as a reversible pump, which delivers hydraulic medium from the tank 6 in a hydraulic system 20 in two opposite delivery directions via a valve arrangement 8 . The valve arrangement 8 comprises a total of four passive valves which are designed as non-return valves. Two of the valves block in the direction of the tank 6. The other two valves open in the direction of cooling and/or lubrication 4.

At the in 1 illustrated embodiment is an actuator 10 for opening and / or closing a parking lock 1. The parking lock 1 includes a parking lock gear 2, which can be locked with the help of a parking lock pawl 3 against rotation. In the state shown, the parking lock 1 is open.

In 1 an engaging and disengaging device 17 is assigned to the actuating element 10 . The disengaging and engaging device 17 is combined with an overtravel mechanism 18 . The overtravel mechanism 18 is integrated into the spindle actuator 30 and comprises a total of four overtravel springs 19.

The driving connection between the rotor 14 of the electric motor 12 of the electromechanical actuating actuator 11 and the pump 9 includes an idle spring device 50. The idle spring device 50 includes a first idle spring 51 and a second idle spring 52. The two idle springs 51, 52 are designed as spiral springs and are arranged between a hub-like rotor body 53 and a pump shaft 54.

The hub-like rotor body 53 is connected in a torque-proof manner to the rotor 14 of the electric motor 12 of the electromechanical actuating actuator 11 . The pump shaft 54 is drivingly connected to the pump 9 .

In 2 the idle spring device 50 is shown enlarged alone. The two idling springs 51, 52 are fastened to the hub-like rotor body 53 radially on the outside. The two idling springs 51, 52 are fastened to the pump shaft 54 radially on the inside. The two idling springs 51, 52 are arranged adjacent in the axial direction.

In 3 the idle spring device 50 with the two idle springs 51, 52 is shown in perspective. The two idle springs 51, 52 are designed as spiral springs and can also be referred to as torsion springs or drive springs.

The hub-like rotor body represents a drive 55. The pump shaft represents an output 56. An arrow 57 indicates in 3 a drive direction indicated.

The first idler spring 51 is partially wound onto the pump shaft of the output 56 . The second idler spring 52 is partially wrapped in the hub-like rotor body of the output 56 . If the drive 55 is now rotated in the drive direction 57 , the first idle spring 51 is wound onto the pump shaft and the second idle spring 52 is wound into the hub-like rotor body of the drive 55 .

As soon as the first idle spring 51 is completely wound onto the pump shaft, a torque is transmitted from the drive 55 to the output 56 when the drive 55 is rotated further in the drive direction 57 .

Reference List

1

parking lock

2

parking lock wheel

3

parking lock pawl

4

cooling and/or lubrication

5

transmission

6

tank

7

filter device

8th

valve assembly

9

pump

10

actuator

11

electromechanical actuating actuator

12

electric motor

13

stator

14

rotor

15

storage facility

17

Alignment and alignment device

18

crossing mechanism

19

overtravel spring

20

hydraulic system

30

spindle actuator

31

spindle nut

32

spindle rod

33

actuation path

50

idle spring device

51

first idle spring

52

second idle spring

53

hub-like rotor body

54

pump shaft

55

drive

56

downforce

57

drive direction

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was 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.

Patent Literature Cited

• DE 102018112213 A1 [0002]
• DE 102018114902 A1 [0002]

Claims (10)

Electromechanical actuating actuator (11) with an electric motor (12) which is drivingly connected to a pump (9) which is used to supply cooling and/or lubrication (4) with a suitable medium, and with an actuating element (10) which can be displaced translationally along an actuating path (33) with the aid of the electromechanical actuating actuator (11), characterized in that the driving connection between the electromechanical actuating actuator (11) and the pump (9) comprises an idle spring device (50) which allows a defined number of relative rotations in opposite directions of rotation before torque is transmitted via the drive connection, without a torque driving the pump (9) being transmitted via the drive connection. Electromechanical actuating actuator claim 1 , characterized in that the idling spring device (50) comprises at least two idling springs (51, 52) which act in opposite directions in the event of a relative rotation. Electromechanical actuating actuator claim 2 , characterized in that the idling springs (51,52) are designed as spiral springs wound in opposite directions. Electromechanical actuating actuator claim 2 or 3 , characterized in that the idling springs (51,52) are arranged axially adjacent. Electromechanical actuating actuator according to one of claims 2 until 4 , characterized in that the idling springs (51, 52) are each connected non-rotatably with a radially outer/inner end to a hub-like rotor body (53) of the electric motor (12) and are non-rotatably connected with a radially inner/outer end to a pump shaft (54). Electromechanical actuating actuator claim 5 , characterized in that a first idle spring (51) is wound with a defined number of idle windings in the hub-like rotor body (53). Electromechanical actuating actuator claim 6 , characterized in that a second idle spring (52) is wound onto the pump shaft (54) with a defined number of idle windings. Electromechanical actuating actuator claim 7 , characterized in that the no-load springs (51,52) are arranged and designed in such a way that the hub-like rotor body (53) is rotated with little torque relative to the pump shaft (54) until a spring band of the second no-load spring (52) is completely wound up on the pump shaft (54), before a torque is transmitted from the hub-like rotor body (53) to the pump shaft (54) via the second no-load spring (52). No-load spring device (50), in particular no-load spring (51, 52), for an electromechanical actuating actuator (11) according to one of the preceding claims. Method for operating an electromechanical actuating actuator (11) according to one of claims 2 until 8th in a hydraulic system (20), characterized in that a drive (55) of the electromechanical actuating actuator (11) can perform a specific number of revolutions freely in relation to an output (56) with the pump (9) until one of the idling springs (51, 52) is wound up/unwound.

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