ACTIVATING A PARKING BRAKE

Abstract

An actuator element is provided for a parking brake that has a mechanically acting actuating mechanism and that can be coupled via a shiftable clutch device to a pump drive of a hydraulic system of a primary assembly by means of a shiftable clutch device in order to activate the parking brake

Claims

1-17. (canceled)

18. A system for activating a parking brake of a motor vehicle, which parking brake is provided as a secondary part of primary components of a primary assembly to be supplied with pressurized oil, cooling oil, and/or lubricating oil, the system comprising: an actuator element for transferring the parking brake at least one of from a release position into a locking position and from the locking position into the release position; and a pump device for generating at least one of a hydraulic pressure and a hydraulic volume flow for supplying the primary components with pressurized oil, cooling oil and/or lubricating oil; wherein the pump device is assigned pump drive elements; wherein the actuator element includes a mechanical actuating mechanism and can be coupled at least indirectly via a shiftable clutch device to one of the pump device and the pump drive elements assigned to the pump device such that the parking brake can be transferred at least one of from the release position into the locking position and from the locking position into the release position by the mechanically acting actuating mechanism.

19. The system of claim 18, wherein the mechanical actuating mechanism has a drive element and an output element, wherein the drive element is placed in positive locking engagement with the output element by closing the clutch device.

20. The system of claim 18, wherein the mechanical actuating mechanism has a drive element and an output element, and the drive element is set in rotation by closing the clutch device.

21. The system of claim 20, wherein the drive element and the output element are continuously in positively locking engagement with one another such that by closing the clutch device the output element is moved in a translational fashion.

22. The system of claim 18, wherein the actuating mechanism is a spindle drive.

23. The system of claim 18, wherein the clutch device is electromagnetically activatable.

24. The system of claim 18, wherein the pump device is drivable by an electric motor that at least also indirectly drives the actuator element when the clutch device is closed.

25. The system of claim 18, further comprising an electric motor configured to rotate in a release direction of rotation to transfer the parking brake from the locking position into the release position, and further configured to rotate in a locking direction of rotation opposed to the release direction of rotation to transfer the parking brake from the release position into the locking position.

26. The system of claim 18, further comprising an electronic control unit programmed to cause actuation of the actuatable actuating mechanism.

27. A method for activating a parking brake of a motor vehicle, which parking brake is provided as a secondary part of primary components of a primary assembly to be supplied with pressurized oil, cooling oil, and/or lubricating oil, the method comprising: closing a shiftable clutch device to couple a mechanical actuating mechanism and at least one of a pump device and pump drive elements assigned to the pump device; transferring the parking brake from at least one of from a release position into a locking position and from the locking position into the release position by the actuating mechanism which is provided on an actuator element; and releasing the clutch device after transferring the parking brake from one of into the locking position from the release position and into the release position from the locking position.

28. The method of claim 27, wherein the mechanical actuating mechanism has a drive element and an output element, the method further comprising placing the drive element in positive locking engagement with the output element by closing the clutch device.

29. The method of claim 27, wherein the mechanical actuating mechanism has a drive element and an output element, the method further comprising setting the drive element in rotation by closing the clutch device.

30. The method of claim 28, further comprising converting a rotational movement of the drive element into a translational movement of the output element to transfer the parking brake from one of into the locking position from the release position and into the release position from the locking position.

31. The method of claim 29, further comprising converting a rotational movement of the drive element into a translational movement of the output element to transfer the parking brake from one of into the locking position from the release position and into the release position from the locking position.

32. The method of claim 27, wherein an electric motor is provided for driving the pump device, and in order to transfer the parking brake from the locking position into the release position the electric motor rotates in a release direction of rotation, and in order to transfer the parking brake from the release position into the locking position it rotates in a locking direction of rotation which is opposed to the release direction of rotation.

33. An electronic control unit for controlling an activation system for activating a parking brake of a motor vehicle, which parking brake is provided as a secondary part of primary components of a primary assembly to be supplied with pressurized oil, cooling oil, and/or lubricating oil, programming of the electronic control unit including programming for: closing a shiftable clutch device to couple a mechanical actuating mechanism and at least one of a pump device and the pump drive elements assigned to the pump device; transferring the parking brake from at least one of from a release position into a locking position and from the locking position into the release position by the actuating mechanism which is provided on an actuator element; and releasing the clutch device after transferring the parking brake from one of into the locking position from the release position and into the release position from the locking position.

34. The electronic control unit of claim 33, wherein the mechanical actuating mechanism has a drive element and an output element, the electronic control unit further programmed for placing the drive element in positive locking engagement with the output element by closing the clutch device.

35. The electronic control unit of claim 33, wherein the mechanical actuating mechanism has a drive element and an output element, the electronic control unit further programmed for setting the drive element in rotation by closing the clutch device.

Description

[0022] Further features and advantages can be found in the dependent claims and the following description of exemplary embodiments with reference to the drawings, in which:

[0023] FIG. 1 shows an activation system for hydraulically activating a parking brake of a motor vehicle according to the prior art, and

[0024] FIG. 2 shows an activation system for activating a parking brake of a motor vehicle having an actuator element which has a mechanical actuating mechanism.

[0025] FIG. 1 shows a concept which is basically known from the prior art, for activating a parking brake of a motor vehicle by means of an actuator element which has a hydraulic actuating mechanism.

[0026] Hydraulic pressure is built up in a pressure line 2 by means of a pump device 1 which is driven by means of an electric motor M. The pressure line is connected to a slide valve 6 (4/2 spool type solenoid valve) which can be actuated electromagnetically and by means of the circuit of which a first line strand 3 or a second line strand 4 can optionally be used as a pressure feed line leading to a hydraulic actuator element 5, while the respective other line strand functions as a largely pressure-free return line.

[0027] When hydraulic pressure is applied to the first line strand 3 (this corresponds to the position of the slide valve 6 illustrated in FIG. 1) the parking brake is transferred into a release position by means of the hydraulically activated actuator element 5. In this release positon, an engagement lever 7 of the parking brake, pre-tensioned by means of a spring, is disengaged from a corresponding opposing element, here for example a locking ring 9 which interacts, in a manner not illustrated in the Figure, with a part of the drive train in such a way that when the engagement lever 7 is in engagement with the locking ring 9 the parking brake is activated.

[0028] If the 4/2 slide valve 6 is switched starting from the position shown in FIG. 1, and therefore pressure is applied to the second line strand 4, the actuator element 5 is pulled back from the position shown in FIG. 1, with the result that an actuator cam 8, which is pre-tensioned, is positioned against the engagement lever 7 and forces the engagement lever 7 against the locking ring 9 in such a way that the engagement lever enters into a positive locking engagement with the locking ring 9 as soon as the position of the locking ring 9 permits such positive locking engagement to come about (blocking position of the parking brake).

[0029] In order to hold the parking brake in the release position shown in FIG. 1, a locking latching means 12 which can be actuated by means of a control device (ECU) is provided, which locking latching means 12 is capable of acting on the actuator element 5 in order to secure it in a position which ensures the release positon of the parking brake.

[0030] A supply line 13 which is provided with a hydraulic control valve 11 is connected to the pressure line 2. When the control valve 11 is open, hydraulic fluid as pressurized oil, cooling oil, or lubricating oil can be extracted from the hydraulic circuit shown in FIG. 1 or the hydraulic fluid reservoir 10 and fed via the supply line 13 to other primary components of a primary assembly to which the parking brake activation system is assigned.

[0031] The hydraulic activation concept illustrated in FIG. 1, by means of a hydraulic actuating mechanism, has a comparatively costly hydraulic system with a multiplicity of, in particular, hydraulic components, which leads to the disadvantages described at the beginning.

[0032] In FIG. 2 the reference symbols which have already been used in FIG. 1 are retained insofar as these reference symbols are assigned to functionally identical components.

[0033] FIG. 2 shows, in contrast to FIG. 1, an activation system for activating a parking brake of a motor vehicle which is purely mechanical and therefore does not require a hydraulic actuating mechanism and with which the parking brake can be transferred from the release position shown in FIG. 2 into a locking position or from the locking position into the release position shown in FIG. 2 by coupling to the hydraulic pump 1 and/or to the electric motor M or other pump drive components via a mechanical actuating mechanism of an actuator element 5.

[0034] In FIG. 2, a pump device (hydraulic pump 1) is driven electromotively by means of the motor M. The electric motor M can be driven in two opposing directions of rotation, specifically a locking direction of rotation and a release direction of rotation. Furthermore, the pump device 1 can be embodied as a hydraulic pump which is capable of operating bidirectionally. Depending on the direction of rotation in which the motor M rotates, the parking brake, which is constructed in FIG. 2 according to the parking brake described already with respect to FIG. 1, can be engaged or released by coupling a mechanical actuator element 5 to a part of the pump device 1 which is driven in rotation or to a drive element of the drive chain which drives the pump, by means of a clutch device 16.

[0035] By closing the clutch device 16 and the associated production of a power-transmitting drive connection between the pump device or the drive elements driving the pump device on the clutch drive side and the actuator element 5 on the clutch output side, a drive element 14 of a mechanical actuating mechanism, which can be formed by a spindle rod or spindle nut, is driven in rotation. The drive element 14 is in engagement with an output element 15 of the mechanical actuating mechanism in such a way that the rotational movement of the drive element 14 is converted into a translational movement of the output element 15 (either a spindle nut or a spindle rod depending on the refinement of the drive element 14). The parking brake is released or engaged depending on the direction of rotation of the electric motor in the release direction of rotation or locking direction of rotation.

[0036] Suitable measures ensure that the spindle rod, which functions in FIG. 2 by way of example as the output element 15 of the actuating mechanism, which moves in a translational function, does not rotate along with the spindle nut which is driven in rotation by means of the clutch device 16 and functions in FIG. 2 as a drive element 14 of the mechanical actuating mechanism. When driven by the rotating spindle nut, the spindle rod forces the actuator cam 8, by means of the drive thread of the spindle drive, in the axial direction either into the release position shown in FIG. 2 (motor M rotates in the release direction), or else permits the actuator cam 8 which is pre-tensioned to slide in the opposite direction in that the spindle rod 15 draws back from the position shown in FIG. 2 into a locking position (motor M rotates in the locking direction) in such a way that the actuator cam forces the engagement lever 7, driven by pre-tensioning, into engagement with the locking ring 9 as soon as the locking ring enters into a position which permits engagement of the engagement lever in the locking ring.

[0037] As a result of the fact that the output element 15 is secured against rotation about its own axis, the parking brake is also permanently secured in the release position which it assumes when the clutch device is released, without a need for an additional securing mechanism. This is because the internal self-locking of the thread of the spindle drive, together with the securement of the output element 15 against rotation, prevents undesired sliding of the actuator cam 8.

[0038] The clutch 16 can be actuated by the same electronic control unit (ECU) which also actuates the hydraulic pump 1 and is activated by means of an actuator 17 which is preferably actuated electromagnetically.

[0039] A supply line 13 for supplying primary components of a primary assembly into which the parking brake activation system is integrated is connected to the hydraulic pump 1. Hydraulic fluid can be fed to the respective components via the supply line 13 in order to activate hydraulic actuators or to lubricate components (gearwheels, bearings, clutches etc.).