ACTUATOR FOR MOTOR VEHICLE APPLICATIONS

Abstract

An actuator for motor vehicle applications, in particular for motor vehicle closing devices, comprising an electric motor, an actuating element which can be directly or indirectly acted upon via a drive train, and, arranged on a drive shaft of the electric motor, a drive wheel with an evoloid toothing, the drive train having at least one crown gear stage.

Claims

1. An actuator for motor vehicle applications comprising: an electric motor having a drive shaft, a drive train, an actuating element that is directly or indirectly acted upon by the motor via the drive train, and arranged on the drive shaft of the electric motor, a drive wheel with an evoloid toothing, wherein the drive train has at least one crown gear stage that includes a crown gear.

2. The actuator according to claim 1, wherein the crown gear is an output wheel of the crown gear stage, and the drive wheel interacts directly with the output wheel.

3. The actuator according to claim 2, wherein an axis of the drive wheel and an axis of the output wheel intersect.

4. The actuator according to claim 2, wherein an axis of the drive wheel and an axis of the output wheel have an axial offset.

5. The actuator according to claim 1, wherein the drive wheel and an output wheel form the crown gear stage, and wherein the crown gear stage is a first gear stage of the drive train and the first gear stage drives a second gear stage of the drive train that includes a gear wheel.

6. The actuator according to claim 5, wherein the second gear stage has an evoloid toothing.

7. The actuator according to claim 5, wherein an axis of the output wheel of the first gear stage and an axis of the gear wheel of the second gear stage are parallel to one another.

8. The actuator according to claim 1, wherein the drive wheel has one to four teeth.

9. The actuator according to claim 5, wherein gears of the first and second gear stages are formed at least partially of plastic.

10. The actuator according to claim 1, further comprising an emergency release that releases the actuating element.

11. The actuator according to claim 1, wherein the drive wheel has three teeth.

12. The actuator according to claim 2, wherein a center axis of the drive wheel is at a right angle with respect to a center axis of the output wheel.

13. The actuator according to claim 5, wherein the second gear stage is a spur gear stage.

14. The actuator according to claim 5, further comprising a switch, wherein the second gear stage includes an elevation that engages with the switch for detecting a position of the actuating element.

15. The actuator according to claim 5, wherein the actuating element includes a toothed rack, and the gear wheel of the second gear stage has toothing that engages with the toothed rack to move the actuating element.

16. the actuator according to claim 10, wherein the emergency release incudes a cable element for pulling the actuating element.

17. the actuator according to claim 10, wherein the emergency release incudes a gear that meshes a gear of a second stage of the drive train to move the actuating element.

Description

[0028] In the drawings:

[0029] FIG. 1 shows a plan view of an actuator designed according to the invention with a view of the drive train, wherein only the components essential for explaining the invention are reproduced; and

[0030] FIG. 2 shows a view of the drive train according to FIG. 1 from a rear view without a housing shell with a housing cover.

[0031] FIG. 1 shows an actuator 1 in a three-dimensional view and a view of a housing shell 2 with an integrated electric motor 3, a drive train 4, an actuating element 5, an emergency release means 6 and a switching means 7. The actuator 1 can be used, for example, to lock a fuel filler flap or a charging plug of an electric vehicle. In this case, the actuating element 5 serves as a bolt that can prevent the fuel filler flap from being opened or the charging plug from being pulled out during a charging process, for example. In this respect, FIG. 2 shows the locked state. The actuating element 5 has been moved out of the housing 2 of the actuator 1. The actuating element 5 can be moved in the direction of the arrow P out of the housing 2 or into the housing 2.

[0032] A drive wheel 9 is arranged on a drive shaft 8 of the electric motor 3, wherein the drive wheel 9 can be fitted onto the drive shaft 8, for example. The drive wheel 9 is designed as an evoloid gear 9 and meshes with a crown gear 10. In this exemplary embodiment, the evoloid gear 9 has three teeth. As illustrated by the dot-dash line L, the arrangement between the drive wheel 9 and the crown gear 10 is designed in such a way that there is no axial distance between the drive shaft 8 and the axis 11 of the crown gear 10. In other words, the axes 8, 11 intersect. The evoloid gear 9 and the crown gear 10 form a crown gear stage 12. It should also be noted that the electric motor 3 is accommodated in receptacles 13 of the housing 2 in a form-fitting manner.

[0033] As can be clearly seen in FIG. 2, the crown gear interacts with another gear 14 to form a second gear stage 15. In this exemplary embodiment, the second gear stage is designed as a spur gear stage. The gear 14 is provided with a toothing only in certain areas, and is additionally formed with a peripheral elevation 16 in some areas, wherein the elevation 16 can be brought into engagement with the switching means 7, in this case a microswitch. The gear wheel 14 thus serves, on the one hand, to transmit the torque to the actuating element and, on the other hand, to detect the position of the actuating element 5. The position of the actuating element 5 shown in these FIGS. 1 and 2 is the locked position, wherein the locked position corresponds to a release of the switching means 7. In the retracted state of the actuating element 5, the gear 14 or the elevation 16 is moved in such a way that the elevation moves into the effective range of the switching means 7 and the switching means 7 is actuated. It is thus possible to detect the position in which the actuating element 5 is located. The axes 11 of the crown gear and the axis 17 of the second gear 14 are arranged parallel to one another in this exemplary embodiment. This allows high transmission ratios to be implemented in the smallest installation space.

[0034] As can again be seen in FIG. 1, the gear 14 of the second gear stage 15 interacts directly with the actuating element 5. For this purpose, a further toothing 18 is formed on the gear 14, and engages directly in a toothing formed as a toothed rack 19 on the actuating means 5. In this exemplary embodiment, the drive train 4 is thus formed by the drive wheel 9, the crown gear 10, the gear 14 and the toothed rack 19, wherein the drive train 4 is driven via the electric motor 3, in this respect the electric motor 3 also forms part of the drive train 4.

[0035] The actuating element 5 is shown in the extended position in FIGS. 1 and 2. If there is a power failure in the extended position, the operator can move the actuating element 5 back into the released position with the aid of an emergency release means 6. For this purpose, for example, a handle part (not shown) which an operator can grasp and actuate can be arranged on the emergency release means 6. The actuating element 5 can thus be moved into an unlocking position by actuating the emergency release means 6 in the direction of the arrow P1.

[0036] FIG. 2 shows an alternative and second possibility for moving the actuating element 5. An actuating means 20 is equipped with a gear 21, wherein the gear 21 in turn meshes with a gear 22 of the second gear stage 15. If the actuating means 20 is moved, for example by means of a tool, the second gear stage 15 can then be moved, as a result of which the actuating element 5 can be moved into a locked or unlocked position. The gear 22 can preferably be assembled and manufactured independently of the gear, but it is also conceivable to form the gear 22 in one piece with the gear 14.

[0037] The actuating means 20 can thus serve as an emergency release means, but locking can also be carried out by means of the actuating means 20.

[0038] FIG. 1 shows part of the housing 2, in particular the housing shell 2, and FIG. 2 shows a housing cover for closing the housing 2. The actuating element 5, the emergency release means 6 and the operating means 20 can be guided out of the housing 2 through sealing means 24, 25, in particular elastic sealing means 24, 25.

[0039] As can be clearly seen in the figures, a compact construction of an actuator 1 can be realized by forming a crown gear stage 12 in combination with a second gear stage 15, wherein the advantages of the crown gear 12 enable construction with minimal external dimensions of the actuator 1. In addition, a high degree of efficiency, for example 0.88, can be achieved, which can be advantageously combined with the very smooth running of the crown gear stage and the transmission of large torques. In this exemplary embodiment, the gear stages 12, 15, 19, as well as the other components housing shell 2, actuating element 5, emergency release means 6, drive wheel 9, crown gear stage 10, 11, 12, receptacle 13, the gears 14, 15, 18, 21, 22, the toothed rack 19, the actuating means 20 and the housing cover 23 are made of plastic, which in turn has a positive effect on the smooth running, the weight and the costs of the actuator 1.

LIST OF REFERENCE SIGNS

[0040] 1 actuator [0041] 2 housing shell [0042] 3 electric motor [0043] 4 drive train [0044] 5 actuating element [0045] 6 emergency release means [0046] 7 switching means [0047] 8 drive shaft [0048] 9 drive wheel [0049] 10 crown gear [0050] 11, 17 axis [0051] 12 crown gear stage [0052] 13 receptacle [0053] 14, 18, 21, 22 gear [0054] 15 second gear stage [0055] 16 elevation [0056] 19 toothed rack [0057] 20 operating means [0058] 23 housing cover [0059] 24, 25 sealing means [0060] P, P1 arrow [0061] L line