KR20210047809A - Electromechanical parking lock actuator - Google Patents

Abstract

The present invention relates to an electro-mechanical parking lock actuator (10) for actuating a parking lock (12) in a vehicle. The parking lock actuator comprises: an electric motor (40); a rotatably or pivotally mounted actuating shaft (46) used for directly or indirectly driving an actuating element (26) acting on a locking pawl (18) of the parking lock (12); and a gear mechanism (44), operably connecting the actuating shaft (46) to the output shaft (42) of the electric motor (40), wherein the gear mechanism (44) includes two gear elements (80, 82) located in an operable connection chain between the output shaft (42) of the electric motor (40) and the actuating shaft, the first gear element (80) between the two gear elements (80, 82) is movably mounted between two positions (N, F), and the first gear element is at least temporarily movable from a normal position (N), in which the first gear element is directly and operably connected to the second gear element (82), to an emergency unlocking position (F), in which the first gear element is moved, from the second gear element (82), sufficiently far away to disconnect the operative connection.

Description

Electromechanical parking lock actuator {ELECTROMECHANICAL PARKING LOCK ACTUATOR}

The present invention relates to an electromechanical parking lock actuator according to the preamble of claim 1. This type of parking lock actuator is used to actuate a parking lock arranged on the vehicle, the lock being provided in turn to prevent the vehicle from rolling inadvertently when the lock is in the locked position. In particular, the invention relates to an electromechanical parking lock actuator of the type used in the automotive industry, for example in electric driven vehicles or vehicles including hybrid transmissions, automated transmissions or automatic transmissions.

A parking lock is required, in particular, in cases where the inhibitory effect of the stationary drive (motor) is insufficient to hold the vehicle in place or cannot be used, for example due to the normally open coupling element. In general, then, the drive train is installed non-rotatably on the output shaft of the transmission and is locked by a parking gear containing toothing, and the parking gear is pivotally mounted on a parallel shaft. pawl) can be locked to the teeth in an interlocking manner. In this case, the parking pawl is prestressed by the force of the return spring to the locked position towards the parking gear or away from the parking gear to the unlocked position. In order to pivot the parking pawl against the force of the return spring, in addition to a hydraulic parking lock actuator, it may be in the form of, for example, a cam or cone or a carrier with two rollers. Electric or electromechanical parking lock used to create a linear motion or at least a substantially linearly extending motion, by means of which an actuating element can be moved against the parking pawl to pivot the pawl. Device actuators may also be used. In order to ensure that the vehicle does not roll away, the parking lock can engage even when the parking pawl does not engage the teeth during operation and stops against the teeth of the parking gear. ) Is usually provided on the actuating element, which, if the vehicle rolls, advances the parking pawl by means of the actuating element so that the pawl engages the teeth of the parking gear.

In addition, as in the present invention, in many cases an option of emergency operation is provided which allows activation in the event of an actuator failure, in particular unlocking the parking lock in the locked position.

From the prior art, an arrangement of a parking lock comprising an electromechanical parking lock actuator is known in which an additional mechanism for emergency unlocking is provided.

Thus, for example DE 10 2010 029 401 A1 is a parking lock assembly with emergency unlocking, including a locking mechanism with an actuating element that is moved back and forth linearly between two axial positions by an actuator in normal operation. In the first axial position of the actuating element, the locking pawl can be adjusted to a release position, and in the second axial position of the actuating element, the pawl can be adjusted to a locking position. . Moreover, the parking lock assembly includes an unlocking mechanism for forcibly unlocking the locking mechanism, and in emergency operation, an actuating element provided with a special recess can be rotated in a second axial position of the actuating element, That way, the locking pawl can occupy the unlocked position by dipping into the recess of the rotated actuating element. For this purpose, the unlocking element is provided with an actuating lever connected to the actuating element for conjoint rotation. In the case of such an assembly, it is disadvantageous in that the emergency unlocking occurs directly from the parking lock itself, not the parking lock actuator, and as a result, the modular configuration required for the selective use of the emergency unlocking mechanism is not possible.

DE 10 2017 219 208 A1 uses an electric motor to displace an actuator rod eccentrically articulated thereto by a translational component acting on the locking pawl of the parking lock via an actuating element. A parking lock assembly for pivoting the shaft is disclosed. In this case, for emergency operation, a manual unlocking device including an idling mechanism is provided, which is operated by an attachable tool to move the locking pawl to the unlocked state in case the electric motor fails. The shaft can also be manually pivoted by rotating the lever. In the case of this design, it is disadvantageous in that an additional idling mechanism is required, and as a result, the complexity of the design of the parking lock assembly is increased as a whole.

Further, WO 2018/228686 A1 discloses a parking lock assembly comprising an emergency unlocking mechanism. The locking mechanism, in normal operation, moves linearly back and forth by a spindle shaft that can be rotated by an electric motor with a spindle nut to adjust the locking pawl of the parking lock to the locked or unlocked position. It has a working element that can be used. The parking lock assembly further includes an unlocking mechanism for forcibly unlocking the locking mechanism. In emergency operation, the spindle shaft is manually operated by the unlocking element after the unlocking element has been displaced from the normal position where the element is at a position away from the spindle shaft to the engaged position where the element is connected to the spindle shaft for torque transmission. Can be rotated. To this end, the unlocking element is connected to an actuator shaft, whereby it can be linearly displaced and rotated. In this case, the relatively large design complexity associated with the additionally required rotatable and linearly displaceable mounted unlocking element is a disadvantage. In addition, since the spindle shaft must be rotated many times and the electric motor must be rotated additionally in order to transfer the locking pawl from the locked position to the unlocked position, the manual operation turns out to be very complex.

The present invention addresses the task of proposing the simplest possible design of an electromechanical parking lock actuator of the type mentioned at the outset, providing the option of manual emergency unlocking for actuating a parking lock in a vehicle.

This problem is solved according to the invention by means of an electromechanical parking lock actuator according to claim 1. Advantageous embodiments and suitable developments of the invention can be found in the dependent claims.

Specifically, in the case of an electromechanical parking lock actuator for actuating a parking lock in a vehicle, the parking lock actuator includes an electric motor having an actuating shaft and an output shaft rotatably or pivotably mounted, the The actuating shaft is used to move the actuating element acting on the locking pawl of the parking lock to lock or unlock the parking lock, either directly or indirectly by means of an interposed element. The parking lock actuator further comprises a gear mechanism, by means of which an actuation shaft or an actuation shaft sleeve suitable for receiving the actuation shaft is operatively connected to the output shaft of the electric motor. According to the invention, the gear mechanism of the parking lock actuator comprises two gear elements located in an actuatable connection chain between the output shaft and the actuation shaft of the electric motor, one of which is designated as the first gear element. The gear element is separated from a normal position that is operably connected directly to another gear element, which is designated as a second gear element, at least in a normal position, such that the operable connection between the first gear element and the second gear element is separated. Adjustable between the two positions in an adjustable manner, at least temporarily so that the working shaft can rotate or pivot independently of the electric motor, with the first gear element away from the second gear element to an emergency unlock position. To be installed.

Unless otherwise specified, within the context of the present application, an operable connecting chain between two components means an assembly of elements, each of which are operably connected to each other in pairs, which together the flow of torque between these two components and/ Or it guarantees the flow of force.

In the case of the design according to the invention, one essential advantage is that the option of emergency unlocking is integrated into the parking lock actuator, so it is not necessary to install it on the parking lock itself in the vehicle. In this way, since a modular configuration of the parking lock actuator can be obtained, the parking lock actuator can be designed selectively with or without an emergency unlocking mechanism with only very small modifications.

Further, in the case of a simple design that does not require complicated mechanisms such as an idling device, an unlocking element, etc., the parking lock actuator according to the present invention is cost effective in production and easy to install. In addition, its compact design allows it to be easily stored even in narrow spaces.

It is particularly advantageous when the gear mechanism comprises at least one pair of gear wheels having two externally toothed gear wheels forming a first and a second gear element and meshing with each other in a normal position. As an alternative, the two gear elements may be operably connected by means of a friction fit in the normal position.

Preferably, in this case, the two gear wheels are separated in the emergency unlock position so that one gear wheel does not drive the other and at least their teeth can only slide past each other.

According to a particularly preferred embodiment of the invention, the parking lock actuator comprises at least one spring element, by means of which the first gear element is urged into a normal position in an elastically restorative manner, 1 The gear element can be moved against the prestressing force of the spring element to the emergency unlock position.

Preferably, the gear mechanism comprises a gear wheel driven by a worm attached to the output shaft of the electric motor. Since the worm gear is self-locking, the gear wheel cannot be rotated when the electric motor is switched off in a de-energized state.

In this case, it is particularly advantageous when the first gear element can be moved to the emergency unlock position by rotation of the second gear element. In the case of a gear wheel having a correspondingly shaped toothed flank, the second gear is rotated when the first gear wheel forming the first gear element is unable to rotate by, for example, a self-locking worm gear. This can be achieved because it can only be deflected outward with respect to the gear wheel.

Moreover, it is advantageous when the second gear element is non-rotatably mounted on the actuating shaft. Thus, rotation of the actuating shaft may first unlock the locked parking lock, and thereby secondly move the first gear element to the emergency unlock position. Thus, even when the electric motor fails, for example, when its power supply is interrupted, the parking lock can be unlocked by rotating the actuating shaft during emergency operation. If the fault is corrected, the parking lock can be activated immediately and smoothly again by the electric motor during normal operation.

According to another particularly preferred embodiment, it is proposed that the first gear element is arranged on a gear shaft mounted such that it can be pivoted or tilted about a pivot axis extending preferably perpendicular to the axis of rotation. , The gear shaft is pivoted or tilted from a normal position in which the first and second gear elements are directly operatively connected to each other, to an emergency unlock position in which the operable connection between the first gear element and the second gear element is separated. Can be.

The pivotable or tiltable mounting of the gear shaft can be achieved in a particularly simple manner in which the end regions of the shaft are respectively mounted on a self-aligning bearing.

Furthermore, it is particularly advantageous if one of the two self-aligning bearings on which the gear shaft is mounted is guided transversely displaceable with respect to the axis of rotation of the gear shaft.

According to another particularly preferred embodiment, the at least one spring element is capable of pushing the displaceably guided self-aligning bearing to the normal position of the gear shaft. Advantageously, the spring element may be a coil spring or a bundle of a plurality of disc springs connected in series, which exerts pressure on the displaceably guided self-aligning bearing.

Advantageously, the actuating shaft may comprise at least one contact surface or one contact profile or one contact hole for an emergency actuating tool that can be attached to or inserted into it, whereby the required operation for emergency operation The rotation of the shaft can be carried out particularly easily.

According to a further preferred embodiment of the invention, the parking lock actuator comprises a housing, in particular formed from a plurality of parts, in which at least an electric motor and a gear mechanism are accommodated and an actuating shaft or an actuating shaft sleeve is mounted. In this case, the free end of the actuating shaft protrudes out of the housing and is intended to be operatively connected to the actuating element outside the housing therein so as to be able to drive the actuating element for action on the locking pawl of the parking lock.

Additional advantages and features of the present invention can be found in the following description of an exemplary embodiment shown in the drawings, wherein:
1 is a schematic diagram of a parking lock including an electromechanical parking lock actuator.
2 is a side view of an electromechanical parking lock actuator according to the present invention.
FIG. 3A is a cross-sectional view of the parking lock actuator from FIG. 2 along section line AA in normal operation.
3B is a cross-sectional view of the parking lock actuator from FIG. 2 along section line AA in emergency operation.
FIG. 4 is a cross-sectional view of the parking lock actuator from FIG. 3A along section line BB.
5 is a cross-sectional view of the parking lock actuator from FIG. 3A along the cross-section line CC.

For simplicity, in the drawings, the same elements are denoted by the same reference numerals even when used in other embodiments.

1 shows an electromechanical parking lock actuator 10 provided for actuating a parking lock 12 arranged in a vehicle. In a manner known per se, the parking lock 12 is mounted in an axially fixed manner and non-rotatably to a gear shaft (not shown) of a vehicle transmission, and has teeth 16 on its outer circumferential side. It includes (14). In order to lock the drive train of the vehicle in an interlocking manner, the parking lock 12 additionally includes a locking pawl 18. The locking pawl 18 is articulate to a transmission housing (not shown) so as to be pivotable about the pivot axis 20, and the locking pawl 18 is pivoted about the pivot axis 20. It includes locking teeth 22 that can be engaged with teeth 16 of the parking gear 14 in a mutually engaging manner. A return spring (not shown) supported against or suspended from the transmission housing acts on the locking pawl 18, and the return spring moves the locking pawl 18 away from the parking gear 14 in an unlocked position. Prestress with.

In order to pivot the locking pawl 18 about the pivot axis 20, an actuating element 26 is provided in the illustrated exemplary embodiment. The actuating element 26 comprises two rollers 28, which can be selectively axially displaced in the locking direction S or the unlocking direction E as indicated by the arrows in FIG. 1 by means of a parking lock actuator 10. I can. Two rollers 28 are guided in a guide element 30 fixed relative to the transmission housing, so that during the axial movement of the actuating element 26 in the locking direction S, one of the rollers 28 is a locking pawl 18 ), while colliding with the inclined contact surface 24, the other roller 28 is supported by the guide element 30. As a result, the locking pawl 18 is opposed to the force of the return spring (not shown in Fig. 1) so that the locking teeth 22 engage the teeth 16 of the parking gear 14. It is pivoted to rotate clockwise around ). Conversely, during the axial movement of the actuating element 26 in the unlocking direction E, the roller 28 is removed from the contact surface 24, and as a result, the locking pawl 18, in FIG. It is pivoted to rotate counterclockwise about the pivot axis 20 due to the force of, and the locking teeth 22 are removed from the teeth 16 and separated from the parking gear 14.

The parking lock actuator 10 shown in Fig. 1 comprises an actuator housing 32, preferably injection molded from a plastic material and molded with a fastening eye 33, the hole ( eye) is used in a vehicle to fix the parking lock actuator 10 to a gear wall (not shown) in a manner known per se, for example by means of screws. In this case, a separately formed motor housing 34 is fixed to the actuating housing 32 by a bayonet joint, and the motor housing accommodates the electric motor therein. The electric motor is used to rotatably drive the actuating shaft of the parking lock actuator 10 by a gear mechanism, the actuating shaft performing rotational motion by a motion conversion device (not shown), in particular by an eccentric device. It converts into an axial motion extending at least approximately axially of the actuating rod 36 carrying the actuating element 26 for the parking lock 12. In normal operation of the parking lock actuator 10, the actuating rod 36 can be driven by an electric motor in the locking direction S or vice versa in the unlocking direction E. In this case, an advancing spring 38 in the form of a helical compression spring and surrounding the actuating rod 36 prestresses the actuating rod 36 and/or the actuating element 26 toward the locked position. do. Both the parking lock 12 and the parking lock actuator 10 according to the present invention can be arranged inside or outside the transmission housing (not shown here) of the vehicle.

The exemplary embodiments shown in Figs. 2 to 5 of the parking lock actuator 10 according to the present invention, in the same manner as the parking lock actuator shown in Fig. Can be placed. For normal operation, the parking lock actuator comprises an electric motor 40 and its output shaft 42 is operably connected to the actuation shaft 46 by a gear mechanism 44. At its free end projecting out of the actuating housing 32, the actuating shaft 46 is in the form of a bushing with an inner splined shaft profile 48 for connection to an eccentric mechanism (not shown here), The mechanism converts the rotational motion of the actuation shaft 46 into at least approximately linear motion of the actuation element 26 acting on the locking pawl 18 of the parking lock 12.

3A-5, the gear mechanism 44, in the exemplary embodiment shown herein, comprises a self-locking worm gear 50, and the worm gear 50 The worm 52 fixed to the output shaft 42 of the motor 40 drives the circumferential teeth of the first gear wheel 54. Due to self-locking, the gear wheel 54 cannot be rotated when the electric motor 40 is switched off in a de-energized state. The gear wheel 54 is integrally formed with a second gear wheel 56 having a smaller diameter to be fixed to rotate, and the second gear wheel 56 is positioned non-rotatably with respect to the gear shaft 58 The third gear wheel 60 is meshed with. The third gear wheel 60 is also integrally formed with the smaller fourth gear wheel 62 to be fixed to rotate, and in turn, the fourth gear wheel 62 is integrated with the operating shaft 46 to rotate. Engages with a fifth gear wheel 64 formed to be fixed, in which case the fifth gear wheel covers an angle of approximately 90° covering the pivot range of the actuating shaft 46 required to drive the parking lock 12 It is only in the form of a gear wheel segment that extends over the rim. The actuating shaft 46 is mounted at its inner end opposite the inner spline shaft profile 48 so that the first gear wheel 54 can rotate together with the second gear wheel 56, a central shaft extension It has a part 66. The shaft extension 66 is mounted on the actuating housing 32 by means of a bearing 68, and a portion of the actuating shaft 46 located in the region of the housing feedthrough is provided by the bearing 70 to the actuating housing. Is mounted on. In this case, the two bearings 68 and 70 are each in the form of a ball bearing.

Both ends of the gear shaft 58 supporting the third gear wheel 60 and the fourth gear wheel 62 are mounted on self-aligning bearings 72 and 74, respectively. The first self-aligning bearing 72, located away from the fourth gear wheel 62, is arranged in a fixed position of the working housing 32 in the inward facing housing rib, while on the fourth gear wheel 62. The adjacent second self-aligning bearing 74 is located in a guide block 76 which is guided in a transversely displaceable manner with respect to the axis of rotation of the gear shaft 58 in the working housing 32. In this case, the guide block 76 is prestressed to the normal position N shown in Fig. 3A by the spring assembly 78 under pressure.

In the normal position (N), in normal operation, the electric motor 40 drives the actuating shaft 46 in the manner described above to lock (S) or unlock (E) the parking lock 12. In this case, the gear wheel 62 forming the first gear element 80 within the context of the invention is directly to the gear wheel 64 forming the second gear element 82 within the context of the present invention. It is operatively connected. In this case, the two gear elements 80 and 82 are located in an operable connection chain between the output shaft 42 and the actuating shaft 46 of the electric motor 40. In the normal position N of the guide block 76 shown in Fig. 3A, the gear shaft 58 and the gear wheel 62 disposed thereon are also arranged in their normal position N, respectively.

In order to be able to unlock the parking lock device 12 located in the locked position during emergency operation, even if the electric motor 40 fails, for example, even if the power supply is interrupted, the present invention can be used. According to this, the first gear element 80 formed by the gear wheel 62 is at least a second gear such that the meshing engagement and thus the operable connection to the second gear element 82 formed by the gear wheel 64 are separated. It can be moved at least temporarily to the emergency unlocking position F, which is moved away from the element 82. To occupy the emergency unlock position F, the guide block 76 is displaced (to the right in Fig. 3b) against the prestressing force exerted by the spring assembly 78, resulting in the gear shaft 58 It is tilted by tilting the two self-aligning bearings 72 and 74.

The gear to the emergency unlock position (F), for example in the case of manual rotation of the actuation shaft 46, which can be easily carried out by hand by means of a tool that can be attached to a pair of flat or cross holes. The inclination of the shaft 58 causes the teeth of the manually rotated gear wheel 64 to disengage from the teeth of the gear wheel 62 that are non-rotatably blocked as a result of the self-locking of the worm gear 50. Because it pushes outward to an extent, it adjusts itself by itself, and the gear wheel 64 can be rotated further with the working shaft 46. As soon as the teeth slide past each other, the spring assembly 78 pushes the guide block 76 so that the first gear element 80 formed by the gear shaft 58 and the gear wheel 62 reaches its normal position (N). Back towards, and thereafter this process is repeated with the subsequent teeth of the gear wheel 64 which is rotated manually. In this regard, the emergency unlocking position F is shown exaggeratedly deflected for clarity in FIG. 3B. In this way, the locking pawl 18 including the locking teeth 22 is completely pivoted out of the teeth 16 of the parking gear 14 by the force of the return spring and thus the parking lock 12 is unlocked again. To the extent, until the actuating element 26 is retracted in the E direction, the manually performed rotation of the actuating shaft 46 can continue.

The parking lock actuator 10 has an electrical interface 84 integrated in the actuating housing 32, which interface is connected to a printed circuit board 86 located in the actuating housing 32. By means of the interface 84 and the printed circuit board 86 the electric motor 40 can be connected to and controlled by an external control device. Furthermore, an additional electrical component of the parking lock actuator 10, for example a position detector (not shown in the figure) for detecting the angular position of the actuation shaft 46, is likewise a printed circuit board 86 and an electrical interface. Can be connected by (84).

Claims (13)

As an electromechanical parking lock actuator 10 for operating the parking lock 12 in a vehicle,
-Electric motor 40,
-An actuating shaft used to directly or indirectly drive an actuating element 26 acting on the locking pawl 18 of the parking lock 12 and mounted rotatably or pivotally; (actuator shaft)(46),
-A gear mechanism 44 operatively connecting the actuating shaft 46 to the output shaft 42 of the electric motor 40
Including,
The gear mechanism 44 comprises two gear elements 80, 82 located in an operable connection chain between the output shaft 42 and the actuation shaft of the electric motor 40, the two Of the gear elements 80, 82, a first gear element 80 is mounted to be movable between two positions N, F, and the first gear element operates directly on the second gear element 82 Parking, characterized in that it is at least temporarily movable from the normal position (N) to which it is possible to be connected, to an emergency unlock position (F) which is moved away from the second gear element (82) at least so as to disengage the operable connection. Lock actuator (10). The method of claim 1,
The gear mechanism 44 forms the first gear element 80 and the second gear element 82 and rolls off each other in the normal position N, externally toothed ( A parking lock actuator (10), characterized in that it comprises at least one pair of gear wheels having two gear wheels (62, 64). The method of claim 2,
In the emergency unlocking position (F), the two gear wheels (62, 64), the parking lock, characterized in that the teeth of the two gear wheels (62, 64) are separated so as to slide from each other Actuator (10). The method according to any one of the preceding claims,
Parking lock actuator (10), characterized in that it comprises at least one spring element (78) for prestressing the first gear element (80) to the normal position (N). The method according to any one of the preceding claims,
The gear mechanism (44) is a parking lock actuator (10), characterized in that it is coupled to the output shaft (42) of the electric motor (40) by a self-locking worm gear (50). . The method of claim 5,
Parking lock actuator (10), characterized in that the first gear element (80) can be moved to the emergency unlock position (F) by rotation of the second gear element (82). The method according to any one of the preceding claims,
Parking lock actuator (10), characterized in that the second gear element (82) is non-rotatably mounted to the actuation shaft (46). The method according to any one of the preceding claims,
The first gear element 80 is arranged on a gear shaft 58 which is pivotably mounted about a pivot axis extending preferably perpendicular to the longitudinal axis, the gear shaft 58 being from the normal position N Parking lock actuator (10), characterized in that it can be pivoted to the emergency unlock position (F). The method of claim 8,
Parking lock actuator (10), characterized in that the end regions of the gear shaft (58) are mounted on self-aligning bearings (72, 74), respectively. The method of claim 9,
A parking lock actuator (10), characterized in that the self-aligning bearing (74) on which the gear shaft (58) is mounted is guided transversely with respect to the longitudinal axis of the gear shaft (58). The method of claim 4 and 10 combined,
Parking lock actuator (10), characterized in that the at least one spring element (78) urges the displaceably guided self-aligning bearing (74) to the normal position (N) of the gear shaft (58). ). The method according to any one of the preceding claims,
The actuation shaft (46) comprises at least one mating surface, a mating profile or a mating hole for an emergency actuating tool that can be attached or inserted. The method according to any one of the preceding claims,
At least a housing (32, 34) in which the electric motor (40) and the gear mechanism (44) are accommodated and on which the actuating shaft (46) is mounted, in particular designed as a plurality of parts, the actuating shaft (46) The free end of the parking lock actuator (10), characterized in that protruding out of the housing (32, 34).

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