Actuator

Abstract

The invention relates to an actuator (28) comprising a motor unit (10), a transmission (12), a driven mechanism (14) and an overload clutch (16), wherein the motor unit (10) is configured to drive the driven mechanism (14) via the transmission (12), and the overload clutch (16) is arranged between the last gear (18) of the transmission (12) and the driven mechanism (14). The motor unit (10) is configured to temporarily move the driven mechanism (14) towards an end stop by means of the transmission (12) after a predetermined number of operating cycles (42) of the driven mechanism (14) at a torque greater than a triggering torque of the overload clutch (16).

Description

Technical Field

[0001] The present invention relates to an actuator. Background Art

[0002] An actuator having a motor unit, a transmission and a driven mechanism is known from the prior art. The motor unit is configured to drive the driven mechanism by means of the transmission. An overload clutch is arranged between the last gear of the transmission and the driven mechanism.

[0003] In known actuators, only a small part of the adjustable range is usually used. This is the case in particular when the actuator is operated at least in the same angular range depending on the application or when the adjustment angle of the actuator is limited by end stops. In particular in actuators with a gear transmission, the result is that only a portion of the teeth, in particular always the same teeth, are always loaded on the output gear of the last gear stage. In particular, even when moving towards the end stops, the maximum load always affects the same teeth of the two gears of the last gear stage. Summary of the invention

[0004] The object of the invention is to provide an actuator having excellent wear resistance. This object is achieved by the characterizing features of claim 1. Advantageous embodiments of the invention are given in the dependent claims.

[0005] The invention relates to an actuator, which comprises a motor unit, a transmission, a driven mechanism and an overload clutch. The motor unit is configured to drive the driven mechanism by means of the transmission, and the overload clutch is arranged between the last gear of the transmission and the driven mechanism.

[0006] After a predetermined number of actuating cycles of the driven mechanism, the motor unit moves the driven mechanism toward the end stop via the transmission at a torque greater than a triggering torque of the overload clutch.

[0007] In particular, the actuator can be used, for example, for motorized adjustment of locking elements of a motor vehicle. The locking elements can be, for example, doors, movable panels, in particular fuel tank caps or tailgates, trunk lids or vehicle rear doors, engine hoods, etc. Alternatively, the actuator can be used for motorized adjustment of other elements that appear suitable to a person skilled in the art in the field of motor vehicle technology, automation technology, in particular building automation, etc.

[0008] A "motor unit" is to be understood in particular as a unit for converting, in particular, electrical energy, chemical energy and / or thermal energy into kinetic energy, in particular rotational energy. "Configured to" is to be understood in particular as a special design and / or construction. An object with a specific function is to be understood in particular as the object fulfilling and / or implementing the specific function in at least one application and / or operating state. In particular, the motor unit comprises at least one drive motor. The drive motor is preferably configured as an electric motor, in particular a brushless DC motor, which is used to convert electrical energy into a rotational movement of a motor shaft. In this context, an "operating cycle" is to be understood in particular as each movement of the driven mechanism within the adjustment region of the actuator, in particular approaching a position within the adjustment region of the actuator and each movement of the driven mechanism towards an end stop during the adjustment operation of the actuator. In this context, the "adjustment operation" of the actuator is to be understood as an operating mode of the actuator for adjusting an element coupled to the driven mechanism of the actuator.

[0009] In this document, a "transmission" is to be understood in particular as a mechanical unit for transmitting and / or changing motion, energy and / or force. In particular, the transmission is arranged in the actuator and transmits the rotational motion of the drive motor of the motor unit to the driven mechanism of the actuator. In particular, when transmitting the rotational motion, the transmission is used to convert the speed, the direction of rotation and / or the torque. The transmission is in particular completely or at least partially configured as a gear transmission, in particular a spur gear transmission. In particular, at least the last gear of the transmission is configured as a gear shift gear, in particular a spur gear shift gear. In particular, the first transmission element of the transmission, in particular the first gear, is non-rotatably arranged on the motor shaft of the drive motor of the motor unit and is directly driven by the drive motor. The last gear of the transmission, in particular the last gear of the transmission, is in particular used to transmit the rotational motion transmitted by means of the transmission to the driven mechanism of the actuator.

[0010] The overload clutch can be arranged in the actuator so that in the event of an overload, the drive side is mechanically decoupled from the driven side, thereby avoiding damage to the drive motor of the motor unit, the transmission and / or other components in the drive train of the actuator. In order to transmit the rotational drive motion, in particular, from the drive side to the driven side, the overload clutch has in particular at least two clutch elements, wherein at least one first clutch element is arranged on the drive side and at least one second clutch element is arranged on the driven side. In the state where the overload clutch is engaged, the drive motion can be transmitted via the clutch element, wherein the clutch elements are engaged with each other in a form-locked and / or force-locked manner in the engaged state to transmit the drive motion, and can be disengaged in the event of an overload. Preferably, the overload clutch can be configured as a friction clutch, a locking clutch or an electromagnetic clutch, for example. The overload clutch is preferably arranged directly between the last gear of the transmission, in particular the last gear and the driven mechanism.

[0011] During the regulating operation of the actuator, the driven element is moved during each operating cycle with a torque that is less than the release torque of the overload clutch, in particular the driven element is moved towards the end stop. After a specified number of operating cycles of the driven element, the regulating operation is changed to the rotating operation. "Rotating operation" is to be understood in particular as an operating mode of the actuator in which the transmission is rotated relative to the driven element. In the rotating operation, the motor unit is configured to temporarily move the driven element with the aid of the transmission at a torque that is less than the release torque of the overload clutch (German: ) towards the end stop. By exceeding the trigger torque of the overload clutch, the clutch element of the overload clutch is disengaged and the transmission is rotated relative to the driven mechanism. The driven mechanism is moved towards the end stop with a torque greater than the trigger torque of the overload clutch only temporarily, in particular for a limited period of time, within the rotational operation of the actuator or until a predetermined rotational angle is reached. After the transmission has been rotated relative to the driven mechanism, the actuator returns from the rotational operation to the regulating operation of the actuator.

[0012] This design provides an actuator of this type with advantageous wear characteristics. This can be achieved in particular by rotating the transmission relative to the driven element so that, immediately after the rotation, different teeth of the transmission are loaded during the actuator's adjustment operation than before the rotation. This makes it possible to distribute the load and / or wear evenly over the teeth of the transmission, thereby making it possible to achieve in particular a longer service life of the actuator, in particular a longer service life of the transmission of the actuator. As an alternative or additional effect, higher loads can be achieved while maintaining the service life of the actuator.

[0013] It is also proposed that the motor unit includes at least one drive motor and at least one control unit, wherein the control unit is used to control the drive motor and to detect the operating cycle of the driven mechanism. "Control unit" should be understood in particular as an electronic unit, which is particularly configured to control and / or adjust the speed, rotation direction and / or rotation angle of the drive motor or the driven mechanism. Preferably, the control unit includes a calculation unit and in particular a storage unit in addition to the calculation unit, the storage unit has a control and / or regulation program stored therein, and the control and / or regulation program is executed by the calculation unit. In particular, the control unit controls the drive motor during the adjustment operation of the actuator to move the driven mechanism and additionally detects the operating cycle of the driven mechanism, and counts. If the number of operating cycles of the driven mechanism reaches the number previously specified and stored in the memory of the control unit, the control unit controls the drive motor in the rotation operation, the drive motor causes the driven mechanism to move to the end stop, and a torque greater than the trigger torque of the overload clutch is applied to the driven mechanism via the transmission. Optionally, the angles that have been moved on all operating cycles can be added and converted to rotation operation after reaching a predetermined total angle. Advantageously, the change from the regulating operation of the actuator to the rotational operation takes place after a predetermined number of operating cycles, in particular from a displacement position of the driven mechanism, which is located at the end stop or at least in the vicinity of the end stop. Undesired adjustments of the displacement position of the driven mechanism can thus be limited to a minimum in an advantageous manner during the change from the regulating operation of the actuator to the rotational operation. If the driven mechanism is not located at a displacement position at or in the vicinity of the end stop when the predetermined number of operating cycles is reached, the change from the regulating operation of the actuator to the rotational operation can be delayed in particular for a long time by the control unit until the driven mechanism is brought into a displacement position at or in the vicinity of the end stop during the rotational operation. After the transmission has been rotated relative to the driven mechanism, the regulating operation of the actuator is assumed again by the control unit. Advantageously, the change from the regulating operation of the actuator to the rotational operation can thus be made.

[0014] It is further proposed that the motor unit is used to rotate the transmission by a predetermined rotation angle relative to the driven mechanism after a predetermined number of operating cycles of the driven mechanism. In particular, the rotation angle by which the transmission is rotated during the rotary operation of the actuator is set in such a way that in the adjustment operation immediately following the rotary operation, in particular over the entire adjustment range of the actuator, other teeth of the last gear stage, i.e. different teeth than in the adjustment operation preceding the rotary operation, are loaded. This advantageously distributes the loads and wear in the transmission, thereby achieving an advantageously long service life of the transmission and the entire actuator.

[0015] A method for operating an actuator is also proposed, the actuator having a motor unit, a transmission, a driven mechanism and an overload clutch, wherein the motor unit is arranged to drive the driven mechanism by means of the transmission, the overload clutch is arranged between the last gear of the transmission and the driven mechanism, wherein after a specified number of operating cycles of the driven mechanism, the driven mechanism moves toward the end stop with a torque greater than the trigger torque of the overload clutch. During the adjustment operation of the actuator, the driven mechanism moves during each operating cycle with a torque less than the trigger torque of the overload clutch. This also applies in particular to the movement of the driven mechanism toward the end stop. Preferably, during the operation of the actuator, in particular during the adjustment operation of the actuator, the number of operating cycles of the driven mechanism is detected. After a specified number of operating cycles of the driven mechanism, the driven mechanism is temporarily moved toward the end stop by the motor unit by means of the transmission with a torque greater than the trigger torque of the overload clutch. By exceeding the trigger torque of the overload clutch, the clutch element of the overload clutch is disengaged and the transmission is rotated relative to the driven mechanism. By rotating the transmission relative to the output, it is advantageously possible that, immediately after the rotation, different teeth of the transmission are loaded during the adjustment operation of the actuator than before the rotation. Loads and / or wear can thus be distributed evenly over the teeth of the transmission, thereby in particular achieving a longer service life of the actuator, in particular of the transmission of the actuator, in particular of the last gear stage.

[0016] It is further proposed that the transmission is rotated by a predetermined rotation angle relative to the driven mechanism after a predetermined number of operating cycles of the driven mechanism. In particular, the rotation angle by which the transmission is rotated during the rotary operation of the actuator is set in such a way that in the adjustment operation immediately following the rotary operation, in particular in the entire adjustment range of the actuator, other teeth of the last gear stage, i.e. different teeth than in the adjustment operation preceding the rotary operation, are loaded. Optionally, this means that when driving with a high number of end stops, the rotation angle of the driven mechanism is selected to be smaller than the adjustment range of the driven mechanism. This makes it possible to advantageously distribute the loads and wear in the transmission, and thus to achieve an advantageously long service life of the transmission and the entire actuator.

[0017] The actuator according to the invention is not to be restricted to the above-described applications and embodiments. In particular, the actuator according to the invention can have a number of individual elements, components and units different from the number described therein in order to fulfill the functions described therein. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Further advantages can be derived from the following description of the drawings. Embodiments of the invention are shown in the drawings. The drawings, the description and the claims contain a combination of various features. A person skilled in the art can also consider these features separately and form other advantageous combinations.

[0019] It shows:

[0020] Figure 1 a schematic diagram showing the actuator; and

[0021] Figure 2 A flow chart showing a method for operating an actuator. DETAILED DESCRIPTION

[0022] Figure 1 Schematic diagram of an actuator 28 is shown. The actuator 28 has a motor unit 10, a transmission 12 and a driven mechanism 14. The motor unit 10 is configured to drive the driven mechanism 14 by means of the transmission 12. An overload clutch 16 is also arranged between the last gear stage 18 of the transmission 12 and the driven mechanism 14. The overload clutch 16 can be configured, for example, as a friction clutch, a lockup clutch or an electromagnetic clutch.

[0023] The transmission 12 is arranged in the actuator 28 to transmit the rotational movement of the drive motor 20 of the motor unit 10 to the output member 14 of the actuator 28. The drive motor 20 is preferably configured as an electric motor, in particular a brushless DC motor. The transmission 12 is configured as a gear transmission, in particular a spur gear transmission. The first gear 34 of the transmission 12 is arranged on the motor shaft 36 of the drive motor 20 in a rotationally fixed manner and is driven directly by the drive motor 20. The last gear 18 of the transmission 12 is arranged to transmit the rotational movement of the drive motor 20 transmitted by means of the transmission 12 to the output member 14 of the actuator 28. An overload clutch 16 is also arranged between the last gear 18 of the transmission 12 and the output member 14. The overload clutch 16 can be configured, for example, as a friction clutch, a locking clutch or an electromagnetic clutch. The overload clutch 16 is configured to mechanically separate the drive side from the output side in the event of an overload, thereby preventing damage to other components in the drive train of the drive motor 20 , the transmission 12 and / or the actuator 28 .

[0024] The motor unit 10 comprises a control unit 22 in addition to the drive motor 20. During the control mode 30 of the actuator 28, the control unit 22 serves, in addition to controlling the drive motor 20, to detect the operating cycles 42 of the output member 14. After a predetermined number of operating cycles 42 of the output member 14, the control unit 22 changes from the control mode 30 to the rotational mode 32. During the rotational mode 32, the motor unit 10 is configured to rotate the transmission 12, in particular the last gear stage 18, relative to the output member 14 about a fixed rotation angle. In order to rotate the transmission 12 relative to the output member after the predetermined number of operating cycles of the output member 14, the motor unit 10 is configured to temporarily move the output member 14 with the aid of the transmission 12 toward an end stop (not shown) at a torque greater than the release torque of the overload clutch 16. By exceeding the release torque of the overload clutch 16, the clutch element of the overload clutch 16 is disengaged and the transmission 12, in particular the last gear stage 18, is rotated relative to the output member 14. After the transmission 12 is rotated relative to the output 14, it returns from the rotation operation 32 to the adjustment operation 30 of the actuator 28. By rotating the transmission 12 relative to the output 14, in the subsequent adjustment operation 30 after the rotation operation 32 is completed, other teeth of the last gear stage 18 of the transmission 14, that is, different teeth than before the rotation operation 32, are loaded.

[0025] Figure 2 A flow chart of a method for operating an actuator 28 is shown. The method for operating an actuator comprises two operating modes of the actuator 28, an adjustment operation 30 for adjusting an element coupled to the output member 14 of the actuator 28, and a rotation operation 32, in which the transmission 12, in particular the last transmission gear 18, is rotated relative to the output member 14. During each operating cycle 42 within the adjustment operation 30, the output member 14 is moved within the adjustment range of the actuator 28. This includes movement to any position within the adjustment range of the actuator 28 and any movement of the output member 14 towards an end stop. In method step 38 of the adjustment operation 30 of the actuator 28, the number of operating cycles 42 of the output member 14 is detected (recorded) and counted by the control unit 22 of the motor unit 10.

[0026] After a predetermined number of operating cycles 42 of the driven member 14, the regulating operation 30 is changed into the rotating operation 32. The control unit 22 changes from the regulating operation 30 into the rotating operation 32. During the rotating operation 30, the driven member 14 is moved toward the end stop in a method step with a torque greater than the triggering torque of the overload clutch 16. By exceeding the triggering torque of the overload clutch 16, the clutch element of the overload clutch 16 is disengaged and the transmission 12, in particular the last gear stage 18, is rotated relative to the driven member 14. The transmission 12 is rotated relative to the driven member 14 by a predetermined rotation angle. In the method step 40 of the rotating operation 32, the rotation angle is detected and compared with the previously predetermined rotation angle. After reaching the predetermined rotation angle, the rotation operation 32 is changed back into the regulating operation 30.

[0027] Reference numerals list

[0028] 10 motor unit; 12 transmission; 14 driven mechanism; 16 overload clutch; 18 gear position; 20 drive motor; 22 control unit; 28 actuator; 30 regulating operation; 32 rotating operation; 34 gear; 36 motor shaft; 38 method steps; 40 method steps; 42 operation cycle; 44 method steps.

Claims

1. An actuator comprising a motor unit (10), a transmission (12), a driven mechanism (14) and an overload clutch (16), wherein the motor unit (10) is configured to drive the driven mechanism (14) via the transmission (12), and the overload clutch (16) is arranged between the last gear position (18) of the transmission (12) and the driven mechanism (14), characterized in that: The motor unit (10) is configured to temporarily move the driven mechanism (14) with the aid of the transmission (12) toward an end stop at a torque greater than a triggering torque of the overload clutch (16) after a predetermined number of operating cycles (42) of the driven mechanism (14), and to rotate the transmission (12) by a predetermined rotation angle relative to the driven mechanism (14), so that after the rotation, different teeth of the transmission (12) than before the rotation are loaded during adjustment operation of the actuator.

2. The actuator according to claim 1, characterized in that The motor unit (10) comprises at least one drive motor (20) and at least one control unit (22), wherein the control unit (22) is used to control the drive motor (20) and to detect an operating cycle (42) of the driven mechanism (14).

3. The actuator according to claim 1 or 2, characterized in that: The overload clutch (16) is formed as a friction clutch, a lockup clutch or an electromagnetic clutch.

4. Method for operating an actuator according to any one of the preceding claims, characterized in that After a predetermined number of operating cycles (42) of the driven mechanism (14), the driven mechanism (14) moves toward the end stop with a torque greater than the triggering torque of the overload clutch (16).

5. The method according to claim 4, characterized in that The number of operating cycles (42) of the driven mechanism (14) is detected during operation of the actuator.

6. The method according to claim 4 or 5, characterized in that: After a specified number of operating cycles (42) of the driven mechanism (14), the transmission (12) rotates by a specified rotation angle relative to the driven mechanism (14).

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