ADJUSTMENT DRIVE

Abstract

Adjustment drive includes an electric motor, a transmission, at least one engaging element, and a resilient element. The transmission has a self-locking transmission stage, a power takeoff, and a safety coupling that separates the self-locking transmission stage from an external torque in response to an excessive external torque introduced via the power takeoff. The safety coupling has a motor-side gearwheel with at least one coupling contour and at least one engaging contour, a power takeoff-side gearwheel, a free-running mechanism formed by the at least one coupling contour, and coupling elements operable to establish a positive-locking connection between the motor-side gearwheel and the power takeoff-side gearwheel. The at least one engaging element is rotationally secured to the motor-side gearwheel or the power takeoff-side gearwheel. The at least one resilient element pretensions the at least one engaging element against the at least one engaging contour to enable haptics of an external movement request introduced via the power takeoff.

Claims

1. An adjustment drive, comprising: an electric motor; a transmission having a self-locking transmission stage, a power takeoff, and a safety coupling operable to separate the self-locking transmission stage from an external torque in response to an excessive external torque introduced via the power takeoff, the safety coupling having a motor-side gearwheel having at least one coupling contour and at least one engaging contour, a power takeoff-side gearwheel, a free-running mechanism formed by the at least one coupling contour, and coupling elements operable to establish a positive-locking connection between the motor-side gearwheel and the power takeoff-side gearwheel such that the coupling elements are pressed in response to the excessive external torque out of the at least one coupling contour to separate the self-locking transmission stage from the external torque; at least one engaging element rotationally secure with respect to the motor-side gearwheel or the power takeoff-side gearwheel; and at least one resilient element operable to pretension the at least one engaging element against the at least one engaging contour so that haptics of an external movement request introduced via the power takeoff is enabled by the engaging contour and an engagement which causes the haptics is formed by the engaging contour.

2. The adjustment drive of claim 1, further comprising: an angle measuring sensor operable to detect the external movement request; and a control unit operable to activate the electric motor in response to the detection of the external movement request.

3. The adjustment drive of claim 1, wherein the free-running mechanism is formed by a recess formed by the coupling contour, the recess having a width that is greater than a width of the coupling element which is pretensioned by the resilient element against the coupling contour.

4. The adjustment drive of claim 1, wherein at least some coupling elements also serve as engaging elements.

5. The adjustment drive of claim 1, wherein at least some engaging elements also serve as coupling elements.

6. The adjustment drive of claim 1, wherein the width of the at least one coupling contours is greater than the width of the at least one engaging contour

7. The adjustment drive of claim 1, wherein the at least one resilient element is operable to pretension the at least one coupling element.

8. The adjustment drive of claim 1, wherein the coupling elements and/or the engaging elements comprise balls.

9. The adjustment drive of claim 1, wherein the engaging elements are arranged opposite each other.

11. The adjustment drive of claim 9, wherein the at least one resilient element is arranged between the engaging elements to pretension the engaging away from each other into the engaging contour.

12. The adjustment drive of claim 1, wherein the coupling elements are arranged opposite each other.

13. The adjustment drive of claim 12, wherein the at least one resilient element is arranged between the coupling elements to pretension the coupling elements away from each other into the coupling contour.

14. The adjustment drive of claim 1, wherein: the engaging elements are arranged opposite each other, and the coupling elements are arranged opposite each other.

15. The adjustment drive of claim 14, wherein: the at least one resilient element is arranged between the engaging elements to pretension the engaging elements away from each other into the engaging contour, and the at least one resilient element is arranged between the coupling elements to pretension the coupling elements away from each other into the coupling contour.

16. The adjustment drive of claim 1, wherein: the motor-side gearwheel and/or the power takeoff-side gearwheel are configured to be hollow, at least axially in portions, and the at least one engaging element and/or the at least one coupling element and/or the at least one resilient element are arranged radially inside the motor-side gearwheel and/or the power takeoff-side gearwheel.

17. An adjustment drive, comprising: an electric motor; a control unit operable to activate the electric motor; a transmission having a self-locking transmission stage, a power takeoff, and a safety coupling operable to separate the self-locking transmission stage from an external torque in response to an excessive external torque introduced via the power takeoff, the safety coupling having a motor-side gearwheel having at least one coupling contour and at least one engaging contour, a power takeoff-side gearwheel, a free-running mechanism formed by the at least one coupling contour, and coupling elements operable to establish a positive-locking connection between the motor-side gearwheel and the power takeoff-side gearwheel such that the coupling elements are pressed in response to the excessive external torque out of the at least one coupling contour to separate the self-locking transmission stage from the external torque; at least one engaging element rotationally secure with respect to the motor-side gearwheel or the power takeoff-side gearwheel; and at least one resilient element operable to pretension the at least one engaging element against the at least one engaging contour contour to enable haptics of an external movement request introduced via the power takeoff.

18. An adjustment drive, comprising: an electric motor; a transmission having a self-locking transmission stage, a power takeoff, and a safety coupling operable to separate the self-locking transmission stage from an external torque in response to an excessive external torque introduced via the power takeoff, the safety coupling having a motor-side gearwheel having at least one coupling contour and at least one engaging contour, a power takeoff-side gearwheel, a free-running mechanism formed by the at least one coupling contour, and coupling elements operable to establish a positive-locking connection between the motor-side gearwheel and the power takeoff-side gearwheel such that the coupling elements are pressed in response to the excessive external torque out of the at least one coupling contour to separate the self-locking transmission stage from the external torque; at least one engaging element rotationally secure with respect to the motor-side gearwheel or the power takeoff-side gearwheel; at least one resilient element operable to pretension the at least one engaging element against the at least one engaging contour to enable haptics of an external movement request introduced via the power takeoff; and a sensor operable to detect the external movement request; and a control unit operable to activate the electric motor in response to the detection of the external movement request.

Description

DRAWINGS

[0025] The disclosure is described below by way of example with reference to the drawings.

[0026] FIG. 1 shows a three-dimensional illustration of an adjustment drive in accordance with the disclosure.

[0027] FIG. 2 shows a sectioned side view of a portion of the transmission of the adjustment drive of FIG. 1, in accordance with the disclosure according to FIG. 1.

[0028] FIG. 3 shows a top view of the portion of the transmission of FIG. 2.

[0029] FIG. 4 shows a sectioned top view, sectioned at the height of the resilient elements and coupling elements, towards the portion of the transmission of FIG. 2.

[0030] FIG. 5 shows a detailed left side view of the portion of the transmission of FIG. 3.

[0031] FIG. 6 shows a detailed right side view of the portion of the transmission of FIG. 3.

DESCRIPTION

[0032] FIG. 1 illustrates an adjustment drive in accordance with the disclosure together with a movement request 8, i.e., an external torque, which can be applied from the exterior, for example, via a handle, to the power takeoff 4 of the adjustment drive.

[0033] The adjustment drive comprises an electric motor 1 and a transmission 2. The transmission 2 in turn comprises a self-locking transmission stage 3 which can use, for example, a worm gear, a power takeoff 4, via which an element which is intended to be adjusted, such as a flap, door, etc., can be moved and additional transmission stages which can be located between the self-locking transmission stage 3 and the power takeoff 4.

[0034] The transmission 2 comprises a safety coupling 6 which is configured to separate the self-locking transmission stage 3 in the event of an excessively great torque, i.e., a torque which is introduced via the power takeoff 4, from the external torque. The safety coupling 6 is configured between two coaxial gearwheels of the transmission, i.e., between a gearwheel 10 at the motor and a gearwheel 11 at the power takeoff.

[0035] The adjustment drive further comprises an angle measuring sensor 9 and a control unit (not illustrated), wherein the control unit and the angle measuring sensor 9 are configured so that the angle measuring sensor 9 detects the external movement request 8 and subsequently the control unit activates the electric motor 1 in the case of a sufficiently powerful movement request 8 and sufficiently great angle change.

[0036] The gearwheel 10 at the motor and the gearwheel 11 at the power takeoff together with the haptic-determining engagement 5 and the safety coupling with free-running mechanism 6 are illustrated in FIGS. 2 to 6 in greater detail. The gearwheel 10 at the motor is at least axially partially configured in a hollow manner so that the elements of the haptic-determining engagement 5 and the safety coupling with the free-running mechanism 6 can be arranged radially inside the gearwheel 10 at the motor. As a result of the common center of the gearwheel 10 at the motor and the gearwheel 11 at the power takeoff, a common axis can be guided.

[0037] The haptic-determining engagement 5 is formed, as illustrated in FIG. 2, from a gearwheel 10 at the motor and a gearwheel 11 at the power takeoff, and from coupling elements 12 which can be connected in a rotationally secure manner to the gearwheel 11 at the power takeoff and which can form positive-locking connections with engaging contours 7b at the gearwheel 10 at the motor in order to connect the gearwheel 10 at the motor to the gearwheel 11 at the power takeoff.

[0038] The haptic-determining engagement 5 uses, as can clearly be seen in FIG. 4 and FIG. 6, a plurality of circumferentially distributed coupling elements 12, i.e., in the illustrated case with balls at the end, for a positive-locking connection between the gearwheel 10 at the motor and the gearwheel 11 at the power-takeoff, wherein the coupling elements 12 in the case of an external movement request, i.e., a torque which is introduced via the power takeoff 4, are pressed by the external torque from the positive-locking connection so that the gearwheel at the power takeoff can rotate relative to the self-locking transmission stage 3 about the free-running mechanism 6. The balls of the coupling elements 12 are arranged at radial end regions of the coupling elements 12. The coupling elements 12 are pretensioned via resilient elements 16, for example, helical pressure springs, into the positive-locking connection, i.e., towards the closed state of the coupling. The strength of the resilient elements 16, the form of the coupling elements 12 and the form of the engaging contour 7b determine the counter-torque which is perceptible at the power takeoff in the event of a movement request, i.e., the haptics of the tip-to-run function.

[0039] The safety coupling 6 has a free-running mechanism 6a formed by coupling contours 7a on the radially internal side of the hollow gearwheel 10 at the motor. The coupling elements 12 are rotationally secure with respect to the gearwheel 11 at the power takeoff are pretensioned by resilient elements 16 against the coupling contours 7a. The haptics of an external movement request 8, i.e., one which is introduced via the power takeoff 4, is therefore not influenced by the free-running mechanism 6a. The edge regions of the coupling contour 7a, the delimitations of the free-running mechanism 6a, determine the greatest possible transmissible torque of the safety coupling. When a great external torque is applied to the power takeoff 4, initially the coupling elements 12 are pressed out of the haptic-determining engagement 5 and the coupling wheel at the power takeoff can be rotated with a specific counter-torque which is determined via the engaging contour 7b in the free-running mechanism 6a with respect to the self-locking transmission stage 3. Should the free-running mechanism 6a be consumed and the external torque is great enough to press the coupling elements 15 inwards over the coupling contour 7b, the power takeoff 4 is then completely separated from the self-locking transmission stage 3.

[0040] In order to form the free-running mechanism 6a, the coupling contours 7a form recesses which are wider than the width of the radial ends, which engage in the coupling contours 7a, of the coupling elements 15 which are pretensioned against the coupling contours 7a by the resilient element 16.

[0041] The coupling elements 12 are at the same time coupling elements 15. Only the form of the coupling contours 7a for coupling elements 15 differ, in the gearwheel 10 at the motor, from the form of the engaging contours 7b for the positive-locking connections of the haptic-determining engagement 5, in which the coupling contours 7a are configured to be wider so that they form a free-running mechanism 6a and the engaging contours 7b are configured to be narrower so that they do not form a free-running mechanism.

[0042] The coupling elements 15 are pretensioned via the resilient elements 16 into the positive-locking connection and consequently into the coupling contour 7a and the coupling elements 12 are pretensioned via the resilient elements 16 into the engaging contour 7b. The coupling elements 15 and the coupling elements 12 comprise at the radial ends thereof balls or other projections.

[0043] As can clearly be seen in FIG. 4, two coupling elements 12 which also constitute two coupling elements 15 are arranged opposite each other and two resilient elements 16 are arranged between the two coupling elements 12 or between the two coupling elements 15 in order to press the two elements apart and to pretension them into the coupling contours 7a and into the engaging contours 7b.

[0044] In order to protect a self-locking transmission from damage, consequently, a safety coupling is installed. In order to identify a movement request 8 (tip to run), an angle measuring sensor 9, for example, a potentiometer or Hall effect sensor, is provided between the self-locking transmission stage 3 and the gearwheel 10 on the drive of the coupling 6. In order to make the haptic requests of the movement request 8 (tip to run) adjustable, in the coupling 6 a free-running mechanism 6a and a simply variable engaging contour 7b are provided.

[0045] The free-running mechanism 6a allows a rotation of the backward-driven gearwheel at the power takeoff side 11 relative to the gearwheel 10 at the drive without activating the uncoupling mechanism of the safety coupling 6.

[0046] In order to define the coupling torque, there are introduced coupling elements 15 which have to be pressed inwards via resilient elements 16 at the end of the free-running mechanism 6a over the coupling contour 7a. In order to define the haptics of the movement request 8 (tip to run) and to damp the free-running mechanism 6a, there are introduced coupling elements 12 which engage in engaging contours 7b via resilient elements 16. The adjustment of the coupling torque and the torque for the movement request 8 is defined by the contour at the respective engaging members, i.e., the engaging contours 7a and 7b, in conjunction with the resilient elements 16. By changing the engaging contours 7b, an independent adjustment of the torques is possible for the movement request 8 and for triggering the safety coupling 6.

[0047] By using independent engaging contours 7b and a free-running mechanism 6a in the safety coupling 6, it is possible when using common resilient elements 16 to bring about different haptic variations by changing the engaging contour 7b because the safety-relevant function of the coupling is separated from the haptic adjustments.

[0048] It is also possible to use independent resilient elements for coupling elements and coupling elements in order to produce an additional adjustability of the engaging torques.

[0049] Should a person apply a torque to the component which is connected to the power takeoff wheel 4, for example, a flap, a handle or the like, this component is flexible in accordance with the form of the engaging contour 7b and the size and form of the free-running mechanism 6a. The counter-torque (haptics) which are perceptible for the person is determined by the engaging contour 7b in this case. The rotation, which occurs in this case, of the power takeoff can be detected via an angle sensor 9 and can be used as a trigger for electrical adjustment.

LIST OF REFERENCE SYMBOLS

[0050] 1 Electric motor [0051] 2 Transmission [0052] 3 Self-locking transmission stage [0053] 4 Power takeoff [0054] 5 Haptic-determining engagement [0055] 6 Safety coupling [0056] 6a Free-running mechanism [0057] 7a Coupling contour (wide) [0058] 7b Engaging contour (narrow) [0059] 8 Movement request [0060] 9 Angle measuring sensor [0061] 10 (First) Gearwheel at motor [0062] 11 (Second) Gearwheel at power takeoff [0063] 12 Engaging element [0064] 15 Coupling element [0065] 16 Resilient element