PUMP ACTUATOR FOR CLUTCH AND GEAR ACTIVATION IN A MOTOR VEHICLE TRANSMISSION

Abstract

Pump actuator for clutch and gear actuator actuation in a motor vehicle transmission, comprising a pump (12, 46, 50) for pumping a working fluid, a drive (14, 52, 82, 86, 94, 100, 108) for actuating the pump (12, 46, 50), a local control unit (16) for controlling the drive (14, 52, 82, 86, 94, 100, 108), and at least one hydraulic interface (A, B) for actuating at least one consumer, wherein at least one cooling device (24, 30, 102) cools the drive (14, 52, 82, 86, 94, 100, 108) and the local control unit (16).

Description

[0001] The invention relates to a pump actuator for clutch and gear selector actuation in a motor vehicle transmission. In particular, the pump actuator can be used in a hydraulic system such as those commonly used in multi-clutch transmissions for motor vehicles.

[0002] Clutches for automated manual transmissions, dual-clutch or multi-clutch transmissions, as well as separable transfer cases and differentials, are designed as either dry or wet clutches. They are actuated either electromechanically or hydraulically, with hydraulic actuation offering advantages in terms of spatial arrangement within the transmission due to the high power density of the actuators. This allows the clutches to be actuated directly, for example, via a central engagement or disengagement mechanism, thus avoiding additional friction losses caused by mechanical gears or similar components.

[0003] German patent application DE 10 2014 216 648 A1 discloses a hydraulic control system with a hydraulic energy source for dual-clutch transmissions of vehicles with an internal combustion engine, in particular commercial vehicles, which can be used for actuating and cooling the clutches. The hydraulic energy source can be driven by either the internal combustion engine or an electric motor.

[0004] From DE 11 2005 000814 B4, a hydraulic system for clutch and gear actuator actuation is known. The system comprises a pump which, via a valve logic with several different valves, can actuate a dual-clutch transmission. The valves are distributed throughout the system. This increases the assembly effort and results in losses in the hydraulic lines due to viscous wall friction caused by long distances between the valves.

[0005] The task is therefore to provide a pump actuator with a simple and compact design and an increased service life.

[0006] The problem is solved according to the invention by a pump actuator having the features of claim 1. Preferred embodiments of the invention are specified in the dependent claims, each of which can individually or in combination represent an aspect of the invention.

[0007] The invention relates to a pump actuator for clutch and gear actuator actuation in a transmission of a motor vehicle, comprising a pump for conveying a working fluid, a drive for actuating the pump, a local control unit for controlling the drive, and at least one hydraulic interface for actuating at least one consumer, wherein at least one cooling device cools the drive and the local control unit.

[0008] The pump actuator can be designed as a controllable, electrically driven, hydraulically acting flow control unit. The pump, the drive, and the local control unit can together form an electric pump actuator, also abbreviated as EPA.

[0009] The pump actuator can integrate all components into a single compact unit, providing a simple, space-saving, and inherently safe hydraulic system for controlling a clutch transmission. This allows the pump actuator to be highly integrated into a clutch transmission and, for example, easily incorporated into existing systems. Furthermore, the pump actuator's design allows for robust construction.

[0010] In particular, the use of a local control unit allows the pump actuator to be installed almost anywhere in the vehicle and to operate independently of the vehicle's central control unit, also known as the electronic control unit (ECU). Furthermore, long cables to the vehicle's central control unit can be eliminated, thus providing shorter signal and power transmission paths.

[0011] The pump can be configured as a single-stage pump or a reversing pump. In a single-stage pump configuration, the pump can only deliver working fluid, such as hydraulic oil, engine oil, or gear oil, from a reservoir to a consumer, such as a partial clutch of a dual-clutch transmission, a gear selector, or a parking brake, to actuate the consumer. A second pump or a return element, such as a return spring, can be used to return the consumer to its resting state. In a reversing pump configuration, the pump can have a first and second delivery direction for the working fluid, such as hydraulic oil, engine oil, machine oil, or gear oil. The first or second delivery direction of the reversing pump can be set by the direction of rotation of the drive, particularly an electric motor.The reversing pump is preferably a fluid pump capable of operating in opposite directions. In particular, the fluid pump can be a hydraulic pump. The hydraulic pump is preferably of positive displacement design. The hydraulic pump can be a vane pump, a gear pump (e.g., external or internal gear pump), a gerotor pump, or a piston pump (e.g., axial or radial piston pump). Specifically, the reversing pump can operate a first consumer, such as a partial clutch, a gear selector, or a parking brake, in the first direction of flow, and a second consumer in the second direction of flow, or pump the working fluid from the first consumer into a reservoir. The connection between the pump and the consumers can be made using hydraulic interfaces.

[0012] The drive can be designed as an electric motor. Depending on the intended use of the pump actuator, the drive can be, for example, a synchronous motor, an asynchronous motor, a permanent magnet motor (e.g., with a ferrite or rare earth magnet), a separately excited motor, or a motor with a variable motor constant.

[0013] In a reversing pump where the first delivery direction actuates a first consumer and the second delivery direction actuates a second consumer, a valve arrangement, such as a dual-pressure valve or directional control valve, can be connected to the first and second delivery directions of the reversing pump to connect the pump to a reservoir for the working fluid. For example, in a dual-pressure valve configuration, the first delivery direction outlet of the reversing pump can be connected to a first side of the dual-pressure valve, and a second side of the dual-pressure valve, opposite the first side, can be connected to the second delivery direction outlet of the reversing pump. The dual-pressure valve can be configured as an AND valve. The dual-pressure valve ensures that only one delivery direction side can be connected to the reservoir.When configured as a directional control valve, the valve can have different switching positions to connect the first or second flow direction output to the reservoir. This allows for a pump actuator with a simple and compact design.

[0014] The cooling device can be designed as a heat exchanger or an electric fan to dissipate the heat generated during operation of the pump actuator from the drive and the local control unit. If designed as an electric fan, the cooling device blows cool air onto the drive and the local control unit. If designed as a heat exchanger, the cooling device can either be located directly on the drive and / or the local control unit or dissipate the heat via cooling lines. The cooling device can dissipate heat passively, for example, using a metallic heat sink attached to the drive and / or the local control unit, or actively, for example, using a pump and a coolant.This prevents the temperature in the drive and / or the local control unit from rising too high during operation of the pump actuator. This ensures a pump actuator with good operational reliability and increases its service life.

[0015] It is preferred that at least one sensor line connects the local control unit to an output of the pump, in particular to a hydraulic section extending to the at least one hydraulic interface, for the purpose of detecting and transmitting a parameter for controlling the drive by the local control unit. The sensor line can either transmit an electrical signal to the local control unit or be a hydraulic section that, for example, transmits the pressure of a flow rate to the local control unit. In particular, the sensor line can be arranged not directly with the pump output, but rather in a hydraulic section between a pump output, for example, a first delivery direction output of the pump, and the hydraulic interface.The parameter detected by the sensor line can be, for example, the pressure of the flow rate of the pumped working fluid, the temperature of the working fluid, and / or the rotational speed of the pump. This simplifies the control of the pump actuator drive.

[0016] Preferably, at least one cooling device, in particular a heat exchanger, is arranged on the drive and / or the local control unit for cooling the drive and / or the local control unit. The heat generated in the drive and / or the local control unit can thus be transferred directly to the cooling device. In this way, the cooling device can cool the drive and the local control unit immediately. The cooling device can dissipate the heat from the drive and / or the local control unit using a coolant. This eliminates the need for long coolant lines, allowing for a simpler and more compact pump actuator. The coolant can be the working fluid or another coolant, such as water, liquid metals, oil, or alcohol.

[0017] In a preferred embodiment, the at least one hydraulic interface is connected to a second cooling device, in particular a heat exchanger. The second heat exchanger can dissipate the heat present in the working fluid to the environment, so that the subsequent actuation of a consumer connected to the hydraulic interface, for example a partial clutch, is not adversely affected by an excessively warm working fluid. In this way, the operational reliability of the transmission actuated by the pump actuator can be improved.

[0018] It is preferred that the cooling device for cooling the drive and / or the local control unit is integrated into a drive housing and / or a local control unit housing. The cooling device can be designed as cooling channels, which are, for example, integrated into the drive housing. A coolant can flow through the cooling channels to, for example, directly dissipate the heat generated in the drive. In this way, an external cooling device that would otherwise need to be attached to the drive or local control unit can be eliminated, allowing for a more compact pump actuator.

[0019] Preferably, a drive housing and / or a local control unit housing is arranged within the cooling device, and the cooling device uses the working fluid as a coolant to cool the drive and / or the local control unit. The cooling device can be designed as a cooling sleeve with cooling channels that completely surrounds the drive and / or the local control unit, or it can be designed as a housing that completely encloses the drive and / or the local control unit. In this way, the drive and / or the local control unit can be completely surrounded by the coolant, allowing the generated heat to be dissipated directly into the coolant. This improves the operational reliability of the pump actuator and increases its service life.

[0020] In a preferred embodiment, a sensor, in particular a differential pressure sensor, is arranged on the local control unit, with at least one sensor line connected to the sensor. In a reversing pump, the differential pressure sensor can determine the pressure on both the first and second delivery directions. Since only one delivery direction in a reversing pump has an elevated pressure at any given time, while the other is at ambient pressure, a signal from one delivery direction is sufficient to determine the pressure. This simplifies the design of the pump actuator; instead of providing a separate pressure sensor for each delivery direction of the pump, the pressure can be determined by a single differential pressure sensor. The sensor can then transmit the signals required to control the actuator to the control unit.In particular, the differential pressure sensor can measure the pressure of the working fluid flow. Using the differential pressure sensor, the drive can operate the pump in such a way that the pump can provide the required pressure to actuate the clutch and / or the gear selector.

[0021] It is preferred that the pump be a variable displacement pump. In this way, the pump's flow rate can be adjusted by changing the volume of a variable displacement piston. In particular, in a reversing pump, a variable displacement piston can be arranged on both sides of the pumping direction, or a variable displacement piston can be arranged only on one side of the pumping direction, and the other side of the pumping direction has a constant flow volume.

[0022] Preferably, the drive and the pump are connected via a main shaft, which is supported in both the drive and the pump. The main shaft can be supported in the drive by a bearing and in the pump by pump mounting brackets. Furthermore, the main shaft's bearing arrangement in the drive can be positioned closer to or further away from the pump, depending on the pump actuator's requirements. The bearing arrangement in the drive can be a ball bearing supported by a bearing holder on the drive housing. In this way, the drive and the pump can be combined into a single module, resulting in a compact and simple pump actuator.

[0023] In a preferred embodiment, a component of the pump, in particular a gear, can be used as a sensor target. This allows the sensor cable to be shortened, resulting in a more compact and simpler pump actuator.

[0024] The invention is explained below by way of example with reference to the accompanying drawings and preferred embodiments, wherein the features shown below can represent an aspect of the invention, either individually or in combination. The drawings show: Fig. 1 a schematic view of a first embodiment of a pump actuator; Fig. 2 a schematic view of a second embodiment of a pump actuator; Fig. 3 a schematic view of a third embodiment of a pump actuator; Fig. 4 a schematic view of a fourth embodiment of a pump actuator; Fig. 5 a schematic view of a fifth embodiment of a pump actuator; Fig. 6 a schematic view of a sixth embodiment of a pump actuator; Fig. 7 a schematic view of a seventh embodiment of a pump actuator; Fig. 8 a schematic view of an eighth embodiment of a pump actuator; Fig. 9 a schematic view of a ninth embodiment of a pump actuator; Fig. 10 a schematic view of a tenth embodiment of a pump actuator; Fig. 11 a schematic view of an eleventh embodiment of a pump actuator; Fig. 12 a schematic view of a twelfth embodiment of a pump actuator; and Fig. 13 a schematic view of a thirteenth embodiment of a pump actuator.

[0025] In the following figure description, the same reference symbols are used for the same components / terms.

[0026] In Fig. Figure 1 shows a first embodiment of a pump actuator 10. The pump actuator 10 comprises a pump 12 in the form of a reversible pump. The pump 12 is connected to a drive 14 in the form of an electric motor. The drive 14 is connected to a local control unit 16. The local control unit 16 controls the drive 14 and thereby the pump 12. The pump 12 is a reversible pump with a first delivery direction and a second delivery direction opposite to the first. The delivery direction is selected by means of the direction of rotation of the drive 14. In this embodiment, the first delivery direction of the pump 12 is shown as an arrow pointing to the left, and the second delivery direction of the pump 12 is shown as an arrow pointing to the right. The first delivery direction of the pump 12 is connected to a reservoir 18 for the working fluid, in this embodiment a hydraulic oil.The second delivery direction of pump 12 is connected via a hydraulic line to a hydraulic interface A for actuating a consumer (not shown) of a transmission (not shown), for example, a partial clutch of a dual clutch. Furthermore, the pump actuator 10 has a sensor line 20 which connects the hydraulic line to the hydraulic interface A with the local control unit 16, so that a sensor in the local control unit 16 can monitor an actuation parameter in the hydraulic line, for example, the flow rate of the working fluid, and the local control unit 16 can control the drive 14 depending on the measured sensor value.

[0027] Fig. Figure 2 shows a second embodiment of a pump actuator 22. The pump actuator 22 comprises a pump 12, a drive 14, and a local control unit 16. The first delivery outlet of the pump 12 is connected to the reservoir 18 via a cooling device 24, for example, a heat exchanger. The cooling device 24 is arranged on the local control unit 16 and the drive 14 and cools them using the working fluid. The heat generated by the local control unit 16 and / or the drive 14 is transferred to the working fluid via the cooling device 24. In this embodiment, the hydraulic interface A of the pump actuator 22 is connected to a second cooling device 26 in the form of an external heat exchanger to dissipate the heat present in the working fluid to the environment. The local control unit 16 uses the sensor line 20 to monitor a parameter in the hydraulic system in order to control the drive 14 and thus the pump 12.

[0028] In Fig. Figure 3 shows a third embodiment of a pump actuator 28. The pump actuator 28 comprises a pump 12, a drive 14, and a local control unit 16. In this embodiment, the local control unit 16 and the drive 14 are arranged in a cooling device 30, for example, a housing, and are completely surrounded by working fluid. The hydraulic interface A is connected to a second cooling device 26 to dissipate the heat absorbed by the working fluid in the cooling device 30 from the local control unit 16 and / or the drive to the environment.

[0029] Fig. Figure 4 shows a fourth embodiment of a pump actuator 32. The pump actuator 32 comprises a pump 12, a drive 14, and a local control unit 16. The first discharge outlet of the pump 12 is connected to a hydraulic interface B for actuating a second consumer, for example, a gear selector. The pump actuator 32 also includes a dual-pressure valve 34. The dual-pressure valve 34 is connected on one side to the first discharge outlet of the pump 12 and on the other side, opposite the first side, to the second discharge outlet of the pump 12. Furthermore, the dual-pressure valve 34 is connected to the reservoir 18 for the working fluid. Only the hydraulic interface A or the second hydraulic interface B can be connected to the reservoir 18 via the dual-pressure valve 34 at any given time. This is determined by the discharge direction of the pump 12.

[0030] In Fig. Figure 5 shows a fifth embodiment of a pump actuator 36. The pump actuator 36 comprises a pump 12, a drive 14, and a local control unit 16. The first delivery direction output of the pump 12 is connected to the hydraulic interface B via a cooling device 24. Furthermore, the pump actuator 36 has a dual-pressure valve 34.

[0031] Fig. Figure 6 shows a sixth embodiment of a pump actuator 38. The pump actuator 38 comprises a pump 12, a drive 14, and a local control unit 16. A differential pressure sensor 40 is arranged on the local control unit 16. The differential pressure sensor 40 is connected to the hydraulic line leading to hydraulic interface A via sensor line 20. Furthermore, the differential pressure sensor 40 is connected to the hydraulic line leading to hydraulic interface B via sensor line 42. Since there is only ever a working pressure in either the hydraulic line leading to hydraulic interface A or the hydraulic interface B at any given time, and the other hydraulic line is balanced with the environment, receiving a signal is sufficient for the local control unit 16 to control the drive 14.

[0032] In Fig. Figure 7 shows a seventh embodiment of a pump actuator 44. The pump actuator 44 comprises a pump 46, a drive 14, and a local control unit 16. In this embodiment, the pump 46 is a variable displacement pump, which can be adjusted by the local control unit 16 depending on the value transmitted via the sensor line 20. In this embodiment, the delivery volume of the pump 46 is adjustable only at the second delivery direction output and remains constant at the first delivery direction output.

[0033] Fig. Figure 8 shows an eighth embodiment of a pump actuator 48. The pump actuator 48 comprises a pump 50, a drive 52, and a local control unit 16. The pump 50 and the drive 52 are connected via a common main shaft 54. The hydraulic path to the hydraulic interface A or B, as well as the dual-pressure valve and the reservoir, are not shown.

[0034] The main shaft 54 ​​is supported in the pump 50 by means of pump brackets 56. The pump 50 also has a countershaft 58. The countershaft 58 and the main shaft 54 ​​each have a gear 60. The countershaft 58 is connected to the main shaft 54 ​​by means of the gears 60 in order to transmit torque from the main shaft 54. The pump 50 comprises a pump housing 62 in which all components of the pump 50 are arranged.

[0035] In the drive 52, the main shaft 54 ​​is supported by a bearing 64, for example, a ball bearing. The bearing 64 is held in a bearing holder 66. Furthermore, the drive 52 has a rotor 68 arranged on the main shaft and a stator 70 surrounding the rotor 68. At the end of the main shaft 54 ​​facing away from the pump 50, there is a magnet holder 72 in which a rotor position magnet 74 is arranged. With the aid of the rotor position magnet 74, a rotor position sensor 76 located in the local control unit 16 can determine the position of the rotor. The drive 52 also includes a drive housing 78 in which all components of the drive 52 are arranged.

[0036] In Fig. Figure 9 shows a ninth embodiment of a pump actuator 80. The pump actuator 80 comprises a pump 50, a drive 82, and a local control unit 16. The hydraulic path to the hydraulic interface A or B, as well as the dual-pressure valve and the reservoir, are not shown. In contrast to Fig. In the drive 82, the positions of the stator 70 and the rotor 68 were interchanged with the positions of the bearing 64 and the bearing holder 66, resulting in a longer bearing distance between the two bearing points. For cooling the drive 82 and the local control unit 16, these can be arranged and operated in a cooling device (not shown), for example, in a surrounding housing, in the working fluid (not shown).

[0037] Fig. Figure 10 shows a tenth embodiment of a pump actuator 84. The pump actuator 84 comprises a pump 50, a drive 14, and a local control unit 16. The hydraulic path to the hydraulic interface A or B, as well as the dual-pressure valve and the reservoir, are not shown. In contrast to the Fig. The drive 86 has cooling channels 90 in the drive housing 88 for cooling the drive 86.

[0038] In Fig. Figure 11 shows an eleventh embodiment of a pump actuator 92. The pump actuator 92 comprises a pump 50, a drive 94, and a local control unit 16. The hydraulic path to the hydraulic interface A or B, as well as the dual-pressure valve and the reservoir, are not shown. In contrast to the Fig. The local control unit 16 is arranged laterally on the drive housing 96, so that the local control unit 16 can be cooled by means of the cooling channels 90 of the drive housing 96. Furthermore, the rotor position sensor 76 is integrated in the drive housing 96.

[0039] Fig. Figure 12 shows a twelfth embodiment of a pump actuator 98. The pump actuator 98 comprises a pump 50, a drive 100, and a local control unit 16. The hydraulic path to the hydraulic interface A or B, as well as the dual-pressure valve and the reservoir, are not shown. In contrast to the Fig. The drive housing 101 has no cooling channels, however, the rotor position sensor 76 is integrated into the drive housing 101. The drive housing 101 is enclosed by a cooling device 102. The cooling device 102 is designed in the form of a sleeve which has cooling channels 104. The local control unit is arranged on the outside of the cooling device 102.

[0040] In Fig. Figure 13 shows a pump actuator 106. The pump actuator 106 comprises a pump 12, a drive 108, and a local control unit 16. The hydraulic line to the hydraulic interface A or B, as well as the dual-pressure valve and the reservoir, are not shown. The drive housing 110 has cooling channels 90. The local control unit 16 is arranged laterally on the drive housing 110 to be cooled by the cooling channels 90. Furthermore, an element of the pump 50 is used as a sensor target for controlling the pump actuator 106. The sensor 112 detects the gear 60 of the countershaft 58. Reference symbol list 10 pump actuator 12 Pump 14 Drive 16 local control unit 18 Reservoir 20 Sensor cable 22 Pump actuator 24 Cooling device 26 second cooling device 28 Pump actuator 30 Cooling device 32 Pump actuator 34 Dual pressure valve 36 Pump actuator 38 Pump actuator 40 Differential pressure sensor 42 Sensor cable 44 Pump actuator 46 Pump 48 Pump actuator 50 pump 52 Drive 54 Main shaft 56 Pump glasses 58 secondary shaft 60 gear 62 Pump housings 64 warehouses 66 Bearing bracket 68 Rotor 70 Stator 72 magnetic holders 74 Rotor position magnet 76 Rotor position sensor 78 Drive housings 80 Pump actuator 82 Drive 84 Pump actuator 86 Drive 88 Drive housings 90 cooling channels 92 Pump actuator 94 Drive 96 drive housings 98 Pump actuator 100 drive 101 Drive housings 102 Cooling device 104 cooling channels 106 Pump actuator 108 Drive 110 drive housings 112 Sensor A hydraulic interface B hydraulic interface

Claims

[1] Pump actuator for clutch and gear actuator actuation in a transmission of a motor vehicle, comprising a pump (12, 46, 50) for conveying a working fluid, a drive (14, 52, 82, 86, 94, 100, 108) for actuating the pump (12, 46, 50), a local control unit (16) for controlling the drive (14, 52, 82, 86, 94, 100, 108), and at least one hydraulic interface (A, B) for actuating at least one consumer, wherein at least one cooling device (24, 30, 102) cools the drive (14, 52, 82, 86, 94, 100, 108) and the local control unit (16). [2] Pump actuator according to claim 1, characterized by that at least one sensor line (20, 42) connects the local control unit (16) to an output of the pump (14, 46, 50) for detecting and transmitting a parameter for controlling the drive (14, 52, 82, 86, 94, 100, 108) by the local control unit (16). [3] Pump actuator according to claim 1 or 2, characterized by that at least one cooling device (24, 30, 102) is arranged on the drive (14, 52, 82, 86, 94, 100, 108) and / or on the local control unit (16) for cooling the drive (14, 52, 82, 86, 94, 100, 108) and / or the local control unit (16). [4] Pump actuator according to one of claims 1 to 3, characterized by that the at least one hydraulic interface (A, B) is connected to a second cooling device (26). [5] Pump actuator according to one of claims 3 or 4, characterized by that the cooling device (24, 30) for cooling the drive (14, 52, 82, 86, 94, 100, 108) and / or the local control unit (16) is integrated in a drive housing (88, 96, 110) and / or in a housing of the local control unit (16). [6] Pump actuator according to one of claims 3 or 4, characterized bythat a drive housing (78, 101) and / or a housing of the local control unit (16) is arranged in the cooling device (30) and the cooling device uses the working fluid as a cooling liquid for cooling the drive (14, 52, 82, 86, 94, 100, 108) and / or the local control unit (16). [7] Pump actuator according to one of claims 1 to 6, characterized by that a sensor is arranged on the local control unit (16), wherein at least one sensor line (20, 42) is connected to the sensor. [8] Pump actuator according to one of claims 1 to 7, characterized by that the pump is a variable displacement pump (46). [9] Pump actuator according to one of claims 1 to 8, characterized by that the drive (14, 52, 82, 86, 94, 100, 108) and the pump (12, 46, 50) are connected to one another via a main shaft (54), wherein the main shaft (54) is mounted both in the drive (14, 52, 82, 86, 94, 100, 108) and in the pump (12, 46, 50). [10] Pump actuator according to one of claims 2 to 9, characterized by that an element of the pump (50) can be used as a sensor target.

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