Servo drive having control unit for controlling brake unit

Abstract

The invention relates to a servo drive (1) for an electrical structural unit of a motor vehicle, comprising: a drive train (2), which comprises a drive gearbox (5) and a drive motor (3) for driving the drive gearbox (5); a brake unit (12) for braking the drive train (2), comprising a self-locking brake gearbox (15) operatively connected to the drive gearbox (5), and a brake motor (13) for driving the brake gearbox (15); and a control unit (29) for controlling the drive motor (3) and the brake motor (13). According to the invention, the control unit (29) is designed in such a way that the drive motor (3) and the brake motor (13) can be operated asynchronously and / or temporally offset in particular in a start-up mode.

Description

Technical Field

[0001] The present invention relates to a servo drive for an electrical structural unit of a vehicle, in particular for a parking brake, a rear spoiler, a steering wheel, a seat, a sunroof, a window, a door and / or a trunk lid, the servo drive comprising: a drive train, the drive train comprising a drive gearbox, in particular a non-self-locking drive gearbox and a drive motor for driving the drive gearbox; a brake unit for braking the drive train, the brake unit comprising a self-locking brake gearbox operatively connected to the drive gearbox, and a brake motor for driving the brake gearbox; and a control unit for controlling the drive motor and the brake motor. Background Art

[0002] DE 101 49 479 A1 discloses a servo drive for movable functional parts in a motor vehicle, such as windows, doors, sunroofs, seat adjustment devices, electric parking brakes, etc. This servo drive comprises a drive motor and a downstream transmission coupled to the movable functional part. At least one transmission part of the transmission is in a permanent active connection with an additional self-locking worm, which is driven by the drive motor and the worm motor in a synchronous motion with the transmission part. The disadvantage of this servo drive is that it is extremely inefficient. Summary of the invention

[0003] In view of the above, an object of the present invention is to provide a servo drive that can overcome the disadvantages known in the prior art, wherein the servo drive is preferably compact, low-cost, low-maintenance, durable, and / or has high efficiency.

[0004] The solution of the present invention for achieving the above-mentioned object is a servo drive having the features of the independent claim.

[0005] The present invention proposes a servo drive for an electrical structural unit of a vehicle. The electrical structural unit that can use the servo drive can be, in particular, a parking brake, a rear spoiler, a steering wheel, a seat, a sunroof, a window, a door and / or a trunk lid. Preferably, the servo drive is a parking brake servo drive, a rear spoiler servo drive, a steering wheel servo drive, a seat servo drive, a sunroof servo drive, a window servo drive, a door servo drive and / or a trunk lid servo drive. The servo drive has a drive train. The drive train includes a drive gearbox. The drive gearbox is particularly constructed as a non-self-locking type. The drive gearbox also has a drive motor for driving the drive gearbox.

[0006] In addition, the servo drive comprises a brake unit for braking the drive train. The brake unit comprises a self-locking brake gearbox, which is in an operative connection with the drive gearbox. Through this operative connection, the brake gearbox can achieve braking of the drive gearbox and the drive motor, especially when the drive motor is not powered. The brake unit also has a brake motor for driving the brake gearbox. The servo drive also has a control unit for controlling the drive motor and the brake motor. The control unit is constructed in such a way that the drive motor and the brake motor can be operated asynchronously and / or staggered in time, especially in a start mode. Advantageously, the drive motor and the brake motor can be controlled by the control unit in such a way that locking in the brake gearbox is prevented and / or released. The advantage is that the brake motor can be designed to be extremely small and low in power, which in turn can reduce the structural volume of the servo drive and reduce manufacturing costs.

[0007] Advantageously, the control unit is designed in such a way that the drive motor and the brake motor can be operated synchronously and / or simultaneously, in particular in normal mode.

[0008] Advantageously, the drive gearbox has at least one first rotatably mounted transmission element. Additionally or alternatively, advantageously, the brake gearbox has at least one second rotatably mounted transmission element. The second transmission element is preferably in operative connection with the first transmission element of the drive gearbox. The first transmission element of the drive gearbox and the second transmission element of the brake gearbox are preferably mounted rotatably about a common rotation axis.

[0009] Additionally or alternatively, it is advantageous if the first transmission element has a first toothing and the second transmission element has a second toothing which is different from the first toothing.

[0010] The second gear train is advantageously designed to enable self-locking of the brake gearbox in cooperation with the third transmission element. This advantageous technical solution of the second gear train in combination with the third transmission element ensures effective self-locking in the brake gearbox. This results in increased safety and reliability of the entire system. This has the advantage of improved operational safety and thus increased user-friendliness.

[0011] Advantageously, the brake gearbox also comprises a third transmission element. The third transmission element preferably has a third gearing corresponding to the second gearing of the second transmission element. The corresponding third gearing of the third transmission element can efficiently transmit forces and movements in the brake gearbox. This ensures optimal performance and efficiency of the system. The resulting advantage is that the efficiency of the system is increased and the durability is improved.

[0012] Advantageously, the second and third transmission elements mesh directly with each other. The direct meshing between the second and third transmission elements results in a direct and efficient force transmission. This can increase efficiency and reduce energy losses. This has the advantage that energy efficiency is improved and operating costs are reduced.

[0013] Advantageously, the brake gearbox comprises or is a worm gearbox. The worm gearbox has a worm and a worm wheel, wherein the worm wheel preferably forms the second transmission element and / or the worm preferably forms the third transmission element. The worm gearbox in the brake unit provides a compact and efficient solution for achieving self-locking.

[0014] In an advantageous improvement, the drive gearbox comprises a fourth transmission element. The fourth transmission element is preferably supported in a manner that it can rotate around a common rotation axis. Preferably, the fourth transmission element is supported downstream of the first transmission element in the driving direction. The downstream transmission element and / or the downstream transmission stage of the drive train are driven by the fourth transmission element. Alternatively, however, the fourth transmission element can also be constructed as a transmission output end.

[0015] In order to construct the actuating drive as space-saving as possible, the first transmission element is advantageously arranged between the second and fourth transmission elements in the axial direction of the common rotation shaft.

[0016] Likewise advantageously, the first, second and / or fourth transmission element together form an anti-rotation unit. The anti-rotation unit can be constructed with or without clearance in the circumferential and / or axial direction of the common rotating shaft. Thus, a clearance can be formed in the first, second and / or fourth transmission element, so that these transmission elements can be twisted relative to each other in the circumferential direction of the common rotating shaft within the range of the clearance. Within the scope of the present invention, an anti-rotation unit that can be twisted within the range of the clearance is anti-rotation. Advantageously, the anti-rotation unit is constructed as multiple gears, in particular as a double gear or a triple gear. In this way, the servo drive can be constructed extremely compactly and space-saving.

[0017] In order to reduce the structural complexity of the servo drive, advantageously, the first, second and / or fourth transmission elements of the anti-rotation unit, in particular the entire anti-rotation unit, are constructed in one piece, in particular are formed of a single piece of material.

[0018] The anti-rotation unit is also advantageously designed as a multi-component unit. In this case, advantageously, the first, second and / or fourth transmission element of the anti-rotation unit are connected. This connection between the first, second and / or fourth transmission element is preferably designed to be detachable and / or inseparable. In addition or as an alternative, advantageously, the first, second and / or fourth transmission element is connected in a form-fitting, press-fitting and / or materially joined manner.

[0019] In an advantageous development of the invention, a gap is formed between the first and second transmission elements which are connected in a non-rotatable manner, so that the first and second transmission elements can be rotated toward each other in the circumferential direction of the common rotation axis within the range of the gap. This prevents the transmission elements from being damaged, in particular in the case of asynchronous operation of the drive gearbox and the brake gearbox.

[0020] Advantageously, the first and second transmission elements are connected by a keyway connection, in particular with or without play. This allows for a very cost-effective and precise rotationally-resistant connection to be formed between the first and second transmission elements.

[0021] In an advantageous development of the invention, the servo drive comprises a housing. Preferably, the anti-rotation unit is arranged in the housing. Additionally or alternatively, the anti-rotation unit is advantageously supported in a manner that it can rotate relative to the housing. Additionally or alternatively, the servo drive advantageously comprises at least one bearing element. The bearing element can be arranged in the housing and / or connected to the housing, in particular in a detachable manner.

[0022] Likewise advantageously, the servo drive comprises at least one bearing element, in particular an axis, an axis body and / or a bearing pin. Preferably, the anti-rotation unit is supported by the at least one bearing element in at least one bearing region, in particular of a housing and / or a carrier element. The anti-rotation unit is preferably supported in this case in a manner that it can rotate about a common rotation axis.

[0023] Preferably, the servo drive has an output shaft, which is formed in particular by the fourth transmission element. As an alternative, the output shaft is advantageously in operative connection with the anti-rotation unit, in particular with the first or fourth transmission element, in particular directly or indirectly via at least one fifth transmission element.

[0024] Advantageously, the drive motor is arranged in the housing. Also advantageously, the drive motor is arranged upstream of the drive gearbox and / or is in operative connection with the drive gearbox, in particular with the first transmission element. The drive motor can transmit the driving force to the driven shaft via the drive gearbox.

[0025] To transmit the driving force from the drive motor to the drive gearbox, the drive gearbox advantageously comprises an electric pinion arranged rotationally fixed on the first motor shaft of the drive motor. In addition or alternatively, advantageously, the electric pinion is in active connection with the first transmission element, in particular directly or indirectly.

[0026] In an advantageous development of the invention, the motor pinion is indirectly operatively connected to the first transmission element via at least one sixth transmission element, in particular via a gear, a belt and / or a bevel gear.

[0027] Advantageously, the first, second, fourth, fifth and / or sixth transmission element is designed as a gearwheel.

[0028] Advantageously, the brake motor is arranged in the housing. Likewise advantageously, the brake motor is arranged upstream of the brake gearbox and / or is in operative connection with the brake gearbox, in particular with the second and / or third transmission element.

[0029] Advantageously, the brake motor comprises a second motor shaft and / or the third transmission element is arranged, in particular directly in a rotationally fixed manner, on the second motor shaft. This allows the servo drive to be constructed extremely compactly.

[0030] Advantageously, only the drive motor is suitable for driving and regulating the servo drive, but not the brake motor. In this regard, advantageously, the brake motor is smaller and / or has a lower electrical power than the drive motor.

[0031] In this regard, it is also advantageous if the brake motor is so small and / or has such a low electrical power that in normal use the locking of the brake gearbox can only be released with the aid of the drive motor. When locked, the second transmission element, in particular the worm gear, and the third transmission element, in particular the worm, are preferably wedged against each other.

[0032] In order to construct the actuating drive as space-saving as possible, it is advantageous if the first motor shaft of the drive motor is arranged parallel to the common rotational axis and / or radially spaced apart from this rotational axis.

[0033] Additionally or alternatively, the second motor shaft of the brake motor is advantageously arranged obliquely, in particular perpendicularly, to the common rotational axis and / or the second motor shaft of the drive motor, preferably at least in one view.

[0034] Furthermore, the second motor shaft of the brake motor is advantageously arranged offset to the common rotation axis and / or the first motor shaft of the drive motor. This allows the servo drive to be constructed in a very space-saving manner.

[0035] Preferably, the control unit is a servo drive control unit. The servo drive control unit preferably forms a structural unit with the housing of the servo drive and / or is integrated in the housing. As an alternative, the control unit is advantageously a structural unit control unit. The structural unit control unit is structurally separated from the housing. Thus, the structural unit control unit can refer to a control unit of a superordinate system, such as a parking brake and / or a vehicle.

[0036] Advantageously, the servo drive is constructed such that the drive motor and the brake motor can be started and / or energized independently of each other and / or independently of each other by the control unit. In addition or alternatively, advantageously, the drive motor and the brake motor each have an independent power supply and / or an independent voltage source.

[0037] In an advantageous development of the invention, the control unit is designed such that the drive motor and the brake motor can be operated in at least one starting mode for avoiding and / or releasing a blocking of the brake gearbox. In normal use, a blocking is formed in particular between the second and third transmission elements, wherein preferably the tooth flanks of the third transmission element are locked together with the corresponding tooth flanks of the second transmission element. Preferably, the control unit is designed such that, in particular when restarting after shutdown and / or when the direction of rotation of the servo drive is reversed, in particular the drive motor and the brake motor are operated first in the at least one starting mode for avoiding and / or releasing a blocking of the brake gearbox. In addition or as an alternative, the control unit is designed such that the drive motor and the brake motor can be operated in a normal mode for adjusting the structural unit.

[0038] Advantageously, the control unit is designed such that the drive motor and the brake motor can be operated asynchronously, in particular in a start mode, and / or can be operated synchronously, in particular in a normal mode. In synchronous operation, the transmission elements of the drive gearbox and the brake gearbox, in particular corresponding to each other, move synchronously with each other. In asynchronous operation, the gearboxes move asynchronously with each other.

[0039] According to an advantageous development of the invention, the control unit is designed such that in normal mode, in particular depending on the drive motor, it operates the brake motor such that the first tooth flank of the third transmission element precedes the corresponding second tooth flank of the second transmission element, in particular by a certain distance. Additionally or alternatively, the control unit is advantageously designed such that in normal mode, in particular depending on the drive motor, it operates the brake motor such that the second tooth flank of the third transmission element follows the corresponding second tooth flank of the second transmission element, in particular by a certain distance. Friction losses in the brake gearbox are thereby avoided, thereby increasing the efficiency of the servo drive.

[0040] Advantageously, the control unit is designed in such a way that it can operate the servo drive in a plurality of starting modes for avoiding and / or releasing blocking of the brake gearbox. In this respect, advantageously, the control unit is designed in such a way that in a first starting mode for avoiding and / or releasing blocking of the brake gearbox, the brake motor is first energized and only after a first time period, in particular additionally, the drive motor is energized. For this purpose, advantageously, the first time period is in particular stored as a corresponding value in the control unit and / or determined by the control unit.

[0041] In addition or as an alternative, the control unit is advantageously designed such that in the first starting mode the brake motor is initially energized in such a way that the third transmission element is rotated in a rotational direction corresponding to the planned adjustment movement of the servo drive. Preferably, the tooth flank of the third transmission element adjacent to or in contact with the corresponding tooth flank of the second transmission element thereby moves away from this corresponding tooth flank of the second transmission element. This advantageously prevents a collision between the second and third transmission elements when the drive motor is energized. The locking between the second and third transmission elements can also be released by the movement of the third element away.

[0042] In an advantageous development of the invention, the control unit is designed such that after a first time period, in a first starting mode, the drive motor is energized in such a way that the second transmission element rotates in a rotational direction corresponding to the planned actuating movement of the servo drive, whereby the tooth flank of the second transmission element preferably follows the outgoing corresponding tooth flank of the third transmission element.

[0043] In this regard, the first time period is also advantageously determined and / or determined by the control unit in such a way that the second transmission element begins to rotate before the other tooth flanks of the third transmission element that have moved forward collide with the corresponding tooth flanks of the second transmission element, thereby preventing collisions between the tooth flanks of the second transmission element.

[0044] According to an advantageous development of the invention, the control unit is designed such that in a second start mode for avoiding and / or releasing a blocking of the brake gearbox, it first controls the start of the drive motor, in particular energizes it, and only after a second time period, in particular additionally controls the start of the brake motor, in particular energizes it. Preferably, the corresponding value of the second time period is stored in the control unit and / or is determined and / or determined by the control unit. In addition or as an alternative, the control unit is advantageously designed such that, while controlling the start of the brake motor and / or energizing it, or after, in the second start mode, it reverses the direction of rotation of the drive motor.

[0045] In this regard, the control unit is advantageously designed such that in the second starting mode, the drive motor is first started, in particular energized, such that the second transmission element is rotated in a direction of rotation corresponding to or opposite to the planned adjustment movement of the servo drive. Preferably, the tooth flank of the second transmission element adjacent to or in contact with the corresponding tooth flank of the third transmission element leaves the corresponding tooth flank of the third transmission element, thereby preferably releasing the blocking.

[0046] Likewise advantageously, the control unit is designed such that, when the second transmission element is subsequently rotated in a direction of rotation opposite to the planned adjustment movement of the servo drive, the drive motor is started in the second start mode, in particular energized, such that its direction of rotation is reversed. The second transmission element is then preferably rotated in a direction of rotation corresponding to the planned adjustment movement of the servo drive.

[0047] Advantageously, the control unit is designed so that it energizes the brake motor in a second starting mode after a second time period so that the third transmission element rotates in a rotational direction corresponding to the planned servo drive adjustment movement, so that the tooth flank of the third transmission element follows the departing corresponding tooth flank of the second transmission element.

[0048] The control unit is also advantageously designed such that the second time period is determined and / or is determined by the control unit such that the third transmission element begins to rotate before the further moving tooth flank of the second transmission element collides with the corresponding tooth flank of the third transmission element.

[0049] The control unit is also advantageously designed in such a way that it operates the drive motor and the brake motor first in the starting mode and / or then in the normal mode after each shutdown and / or when the direction of rotation of the actuating drive is reversed.

[0050] Advantageously, current limit values ​​for the drive motor and / or brake motor are stored in the control unit. Additionally or alternatively, the control unit is advantageously designed such that it operates the drive motor and brake motor in the start-up mode when at least one current limit value is exceeded. Additionally or alternatively, the control unit is advantageously designed such that it operates the drive motor and brake motor in the start-up mode after a shutdown and / or after a reversal of the direction of rotation of the servo drive and / or in particular only when at least one current limit value is exceeded, in particular immediately after a startup, immediately after a reversal of the direction of rotation and / or immediately before the last shutdown.

[0051] Advantageously, the brake unit comprises at least one sensor, in particular a rotation angle sensor and / or an end position sensor. Preferably, the sensor is designed such that the relative position and / or locking between the second gearing of the second transmission element and the third gearing of the third transmission element can be detected and / or determined, in particular indirectly or directly, by means of the sensor.

[0052] In an advantageous development of the invention, the at least one sensor is arranged on the brake motor. Additionally or alternatively, the at least one sensor and / or the control unit are designed such that the position of the second and / or third transmission element, which is preferably adjustable between two end stops within a position range, can be determined.

[0053] Advantageously, at least one start-up mode range for the second and / or third transmission element is stored in the control device, which start-up mode range forms a subrange of the adjustment range. Additionally or alternatively, the control unit is advantageously designed such that the drive motor and the brake motor are operated in the start-up mode, in particular only if the actual position of the second and / or third transmission element detected by the sensor is within the stored start-up mode range.

[0054] In an advantageous development of the invention, the sensor is designed such that a first relative position between a first tooth flank of the third transmission element and a corresponding first tooth flank of the second transmission element can be detected by means of the sensor. Additionally or alternatively, the at least one sensor is designed such that a second relative position between a second tooth flank of the third transmission element and a corresponding second tooth flank of the second transmission element can be detected.

[0055] The invention further provides a method for operating a servo drive. The servo drive is preferably constructed according to the above description, wherein the features mentioned can be used individually or in any combination.

[0056] Advantageously, the servo drive and / or the method are constructed according to the description below, wherein the features mentioned can be applied individually or in any combination. Preferably, the servo drive, in particular for vehicles, has a self-locking function and / or high efficiency. After the self-locking function has been used, the servo drive does not need to be maintained or the locking function is released in another way, but is still fully capable of working. The servo drive comprises a particularly large drive motor and / or a particularly small brake motor. The large drive motor drives a first transmission element with its electric pinion. The electric pinion and the first transmission element are designed to be non-self-locking. The brake motor drives a self-locking third transmission element, in particular a worm. The particularly small brake motor realizes the self-locking function in the servo drive with its worm. The brake motor and the worm are designed in a way so that when the drive motor is running, they run fast enough with the drive gearbox and / or slightly ahead if the transmission clearance allows, and in the process do not affect the drive at the transmission output end, so that the drive gearbox is not decelerated and / or accidentally locked suddenly. The brake motor and the third transmission element, in particular the worm, are preferably not suitable for driving the drive gearbox in addition.

[0057] The brake motor and the third transmission element, in particular the self-locking worm, are not decoupled from the drive gearbox, but are permanently operatively connected to the drive gearbox.

[0058] Due to the geometry of the tooth system, it is almost impossible for the electric pinion and the third transmission element, in particular a self-locking worm, to mesh with the same tooth system and drive the same gear together through the same tooth system geometry. Based on this, the drive motor preferably drives the first transmission element with its electric pinion, and the brake motor drives the second transmission element, in particular the worm wheel, with its third transmission element, in particular its worm. To this end, the first transmission element, in particular the spur gear, and the second transmission element, in particular the worm wheel, are connected in a manner that is as rotationally rigid as possible. This means that when the first and second transmission elements are implemented as an integral unit, the two are connected in a rotationally rigid manner. When the first and second transmission elements are implemented as multiple components, a rotationally rigid connection with or without play can be formed between the two.

[0059] The first and second transmission elements can be constructed together as one piece or as multiple components. In the case where the first and second transmission elements are constructed as multiple components, they can be connected to each other in a non-rotational manner without clearance, for example, by compression or form fit. However, for tolerance reasons, it is also advantageous that the first and second transmission elements can be connected in a non-rotational manner but with clearance. That is, the clearance only allows the second transmission element to rotate to a certain extent relative to the first transmission element. This can be formed, for example, by a hub of the first transmission element and a slightly larger groove at the second transmission element. However, the hub and the groove can also be constructed on another component. There can be a plurality of corresponding hubs and grooves constructed on these two components.

[0060] If the servo drive is used for applications requiring a high reduction ratio and / or a small structural space, for example in the case of an electric parking brake, the fourth transmission element can be connected to the first transmission element and / or the second transmission element, in particular the worm gear, in a rotationally fixed manner. In this case, the above elements together form a three-wheel gear. The three-wheel gear preferably includes a worm gear, a spur gear configured as a first transmission element, and a further spur gear configured as a fourth transmission element. The above elements can be configured separately or together as a multi-component or integrated device. In the three-wheel gear, the fourth transmission element drives the next transmission stage.

[0061] In an alternative embodiment, for example, when a high reduction ratio is not required, the second transmission element, particularly the worm gear and the first transmission element can be constructed as a double gear. In this case, the first transmission element drives the next transmission stage or the transmission output end.

[0062] The three-gear wheel or the double gear wheel is preferably supported in and / or on the housing or other components (such as a carrier element and / or a carrier plate) via a bearing pin. The bearing pin can be supported in a rotationally fixed manner at its bearing point. Alternatively, the bearing pin can be connected to the three-gear wheel or the double gear wheel in a rotationally fixed manner. In this case, the bearing pin is supported in a rotatable manner at at least one bearing point of the housing or housing part.

[0063] As an alternative to at least one bearing pin, a shaft body can be used, on which the double gear is arranged in a rotationally fixed manner. This shaft body can form the driven shaft of the servo drive. This is particularly advantageous in the case of a double gear, wherein preferably no further reduction is subsequently carried out.

[0064] Advantageously, the first transmission element as a component of a three-gear or double gear does not need to directly or immediately follow the drive motor and / or the electric pinion as a transmission stage. Alternatively, other transmission stages or transmission elements, such as belt drives, angle drives, etc., can also be arranged between the electric pinions.

[0065] Likewise advantageously, the three-gear or double-gear as well as the brake motor and the third transmission element, in particular the worm, can be placed close to the transmission output. The brake unit can thus protect the transmission stage between the drive motor and the three-gear or double-gear from continuous adverse stress or damage (for example in plastic gears with creep properties).

[0066] In order to ensure that the servo drive is still able to work without maintenance and does not lock the worm gear after using self-locking under load, it is advantageous that the drive motor and the brake motor are not started simultaneously in subsequent operation after using self-locking under load.

[0067] The locking of a worm gear may be problematic when a load is applied to the worm gear and after self-locking has been used when a low-power brake motor is used to drive the third transmission element, in particular the worm. The locking occurs because the second transmission element, in particular the worm wheel, and the third transmission element, in particular the worm, are wedged together and are triggered, for example, by a high load on the second transmission element, a change in the direction of rotation of the servo drive or by vibrations. The worm and the worm wheel become wedged together when they are meshing, and more specifically, when the worm stops, for example, when the actuator stops, the worm stops too close to one side of the worm wheel tooth flank. Now, if the direction of rotation of the transmission changes and the drive motor and the brake motor are energized at the same time, the following situation will occur: when the worm and the worm wheel move in the same direction, the worm and the tooth flank of the worm wheel collide, which can cause the worm gear to wed. The brake motor is preferably designed to be small. Therefore, the power of the brake motor is preferably less than that of the drive motor, so that the brake motor cannot move the worm out of the locked position, because the tooth surface of the worm wheel is also pressed toward the worm by the drive of the much more powerful drive motor and thus remains wedged. This problem can be solved when the drive motor and the brake motor are controlled to start differently. Advantageously, the start of the less powerful brake motor and the more powerful drive motor is controlled in this way before the normal mode of the servo drive, so as to prevent or release the locking of the worm gear transmission. This can be implemented by two lock release modes, namely the first start mode or the leading lock release mode, and the second start mode or the safety lock release mode. These lock release modes can be used individually or in combination independently of the application situation. Normal operation in which the start of two motors is controlled at the same time is called normal mode.

[0068] As mentioned above, a change in the direction of rotation of the drive motor, for example after a shutdown, can quickly lead to a locking of the brake gearbox, in particular a worm gear. To prevent locking, the brake gearbox is operated in a first start mode or leading lock release mode after a shutdown. To this end, the small brake motor is first energized for a period of time and moves in the desired direction of rotation. Subsequently, the large drive motor is energized in the desired direction. In this mode, the worm is slightly ahead of the worm wheel, i.e., if the worm is too close to the tooth flank of the worm wheel after a shutdown, the worm can be moved away before it collides with the tooth flank of the worm wheel.

[0069] If the servo drive is to be designed to be cost-effective, no additional sensor means can be provided. In this case, the control unit is not aware of the exact position of the worm between the two tooth flanks of the worm wheel. In this case, the control unit is preferably designed such that it operates the servo drive in a first start mode or lock release mode after each shutdown of the servo drive. In this regard, the brake motor is first energized for a period of time in the desired direction of rotation before the drive motor is also energized in the desired direction of rotation.

[0070] It is also possible that the worm approaches the tooth flanks of the worm wheel when the operation is stopped and that the worm moves toward one of the tooth flanks of the worm wheel during operation in the first starting mode or the lock release mode before the drive motor moves the worm wheel in the desired direction of rotation via the drive gearbox. However, this will not lead to a lockup of the worm gear drive only if the worm wheel is driven by a more powerful drive motor and is not wedged by the approach of the worm.

[0071] The first start mode or the lock release mode is sufficient for application situations where there is no large load on the worm wheel. When a sensor mechanism is used, such as a rotation angle sensor, to detect the position of the worm, the control unit can be designed so that the servo drive is controlled to start in normal mode under normal circumstances, and the start is controlled in the first start mode or the lock release mode only when the servo drive stops running and the worm stops too close to one side of the worm wheel tooth surface and the movement in the desired direction may cause a collision.

[0072] If neither of the two motors is driving and the brake gearbox, in particular the worm gear, prevents the drive gearbox and the drive motor from rotating by self-locking, this often results in the worm gear being blocked (mainly when there are high loads on the worm gear). In this case, the blocking of the worm gear is not released. To avoid this, the motors are advantageously subsequently controlled asynchronously and / or sequentially.

[0073] In order to reliably release the self-locking on the worm gear transmission, the worm must be released or removed from the wedging state with the worm wheel when starting or when the direction of rotation is reversed. To this end, the drive motor is briefly energized in the opposite direction. In addition, during the brief energization of the drive motor, the brake motor is energized or started in the opposite direction and / or in the desired direction. By rotating the drive motor in the opposite direction, the corresponding torque is transmitted to the first transmission element. Since the first transmission element is connected or functionally connected to the second transmission element, especially the worm wheel, the torque is also applied to the second transmission element or the worm wheel, so that the second transmission element moves slightly in the opposite direction. Therefore, there is no longer a load applied to the worm from the worm wheel. At the same time, the brake motor is driven in the desired direction so that the worm can move again and lead. In the next step, the drive motor must be energized in the desired direction of rotation. The self-locking is now successfully released and does not cause locking. That is, the actuating drive can be reliably moved out of the self-locking state without causing the worm gear to be locked, or an existing lock of the worm gear can be released thereby.

[0074] The control unit for the drive motor and / or brake motor can be placed in the housing of the servo drive itself or in other control devices of the vehicle.

[0075] In some servo drives, blocking often occurs due to high loads or very small brake motor dimensions. In this case, the control unit can reasonably always control the start of the drive motor and / or brake motor in the first or second starting mode or the blocking release mode at the next switch-on after disconnection. This ensures that the servo drive is always capable of working. In this case, no additional sensors are required, which reduces the cost of the servo drive. However, at least one sensor can be added if necessary.

[0076] In the case of a servo drive used as an electronic parking brake, operation in the second activation mode or the second lock release mode is preferred, since high loads are present at the transmission output of the electronic parking brake. In addition, in this application, a high degree of reliability is required to release the parking brake. The first activation mode or the first lock release mode is sufficient for rear spoilers or window regulators.

[0077] In some servo drives, only in rare cases are there high loads on the worm wheel and worm during operation, for example due to vibrations, temperature fluctuations or long downtimes. In these application cases, the start-up of the servo drive can usually be controlled in normal mode, in which the drive motor and the brake motor are energized and / or their start-up is controlled in parallel and / or synchronously. However, if a blockage occurs, the servo drive must be maintained and is not capable of working. In order to avoid maintenance, the servo drive can be operated in one or both of the above-mentioned start-up modes, in particular as soon as the control unit detects a blockage.

[0078] The control unit can be designed in such a way that in normal mode, the two motors are initially controlled to start and operate simultaneously. The drive motor and the brake motor preferably each have an independent power supply and voltage source.

[0079] Advantageously, a current limit value for the servo drive in normal mode is determined for the brake motor and / or the drive motor. The current limit value is lower than the maximum current value stored or can be the same as the maximum current value. The maximum current value is used to protect the drive gearbox and / or the brake gearbox from damage due to overload. If in normal mode, shortly after the servo drive is started, the brake motor and / or the drive motor exceeds the current limit value, then the worm gear drive is likely to lock up. If the servo drive is stopped in normal mode and the current limit value is exceeded shortly before it stops running, locking may also occur. In one or all of the aforementioned events, the control unit advantageously operates the drive motor and the brake motor in one of the two starting modes before the next switching on.

[0080] Additionally or alternatively, the control unit can be designed such that, after reaching the current limit value in the normal mode and disconnecting the two motors, starting is performed in a first step in the first starting mode. If the first starting mode does not successfully release the blocking (for example due to excessive load on the worm gear, which can be detected, for example, by exceeding the current limit value or by exceeding a stored time value), then starting is performed in a second step in the second starting mode. The current limit values ​​determined for the normal mode, the first starting mode and / or the second starting mode can be identical or different.

[0081] If the current is less than the current limit value and the two motors are disconnected in the normal mode of the servo drive, then the next time the servo drive is turned on, the two motors are started in the normal mode, that is, they are controlled to start at the same time.

[0082] The position of the worm on the brake motor can be determined based on sensors, such as rotational angle sensors or final position sensors. The third transmission element, in particular the worm, has a start mode range or position range, which is preset or determined by the control unit. The start mode range is selected so that within this range, the third transmission element, in particular the worm, is most likely to be blocked. This can be determined empirically, for example, through a large number of tests. If the control unit determines, in particular based on at least one sensor, that the third transmission element, in particular the worm, is within the start mode range or the determined position range, the control unit selects at least one start mode at the next switch-on and / or when the direction of rotation is reversed. If the third transmission element is outside the start mode range in these events, the servo drive operates in normal mode. BRIEF DESCRIPTION OF THE DRAWINGS

[0083] Further advantages of the present invention are described in the following examples.

[0084] Figure 1 is a schematic cross-sectional view of a servo driver according to a first embodiment;

[0085] Figure 2 is a schematic cross-sectional view of a servo driver according to a second embodiment;

[0086] Figure 3a-3c Schematic cross-sectional views of a second and a third transmission element of a brake gearbox of a servo drive at different time points during a first starting mode;

[0087] Figure 4a-4c Schematic cross-sectional views of a second and a third transmission element of a brake gearbox of a servo drive at different time points during a second starting mode in a first rotational direction;

[0088] Figure 5a-5cSchematic sectional views of a second and a third transmission element of a brake gearbox of a servo drive at different points in time during a second starting mode in a second rotational direction opposite to the first rotational direction. DETAILED DESCRIPTION

[0089] Figure 1 and Figure 2 Schematic cross-sectional views of two exemplary embodiments of a servo drive 1 are shown. Figures 3a to 5c In terms of the technical principles described in the above, these servo drives 1 are identical to each other. The only difference is some structural changes, which will be described in detail below. Figure 1 Features of the illustrated embodiments and Figure 2 The features of the illustrated embodiments are identical in terms of technical solution and / or mode of action using the same reference numerals, unless otherwise specified below, which technical solution and / or mode of action are equivalent to the technical solution and / or mode of action of the features described above.

[0090] Figure 1 and Figure 2 The servo drive 1 shown is suitable for an electrical structural unit of a motor vehicle. Electrical structural units that may use the servo drive 1, which are not shown here, may in particular be parking brakes, rear spoilers, steering wheels, seats, sunroofs, windows, doors and / or trunk lids. Preferably, the servo drive 1 is a parking brake servo drive, a rear spoiler servo drive, a steering wheel servo drive, a seat servo drive, a sunroof servo drive, a window servo drive, a door servo drive and / or a trunk lid servo drive.

[0091] according to Figure 1 The servo drive 1 comprises a drive train 2 which can be used to transmit a driving force to adjust a desired structural unit. The drive train 2 has a drive motor 3 . Here, it is preferably an electric motor that can be powered. The drive motor 3 has a motor shaft 4 .

[0092] In addition, the drive train 2 has a drive gearbox 5. The drive gearbox is non-self-locking. In this regard, when the drive motor 3 is disconnected and / or not powered, the drive gearbox can move, in particular rotate, when a force is applied at the transmission output end of the drive gearbox 5.

[0093] The drive gearbox 5 comprises a motor pinion 6 which is connected to the first motor shaft 4 in a rotationally fixed manner. The drive gearbox 5 also has a first transmission element 7 which is rotatably supported. This is preferably a gear, in particular a spur gear. Figure 1 In the embodiment shown, the first transmission element 7 meshes with the electric pinion 6. Therefore, the first transmission element 7 is directly in mechanical connection with the electric pinion 6. The first transmission element 7 has a first gear system 8. Figure 1If the motorized pinion 6 is directly in mechanical operative connection with the first transmission element 7, as in the embodiment shown, the motorized pinion 6 has a tooth system corresponding to the first tooth system 8 of the first transmission element 7. However, alternatively, in an embodiment not shown here, at least one sixth transmission element may also be arranged between the motorized pinion 6 and the first transmission element 7. The sixth transmission element may be a gear, a belt and / or a bevel gear. Therefore, in this alternative embodiment, the motorized pinion 6 is indirectly in mechanical operative connection with the first transmission element 7 via the at least one sixth transmission element.

[0094] like Figure 1 As shown, the drive train 2 has a driven shaft 9. The driven shaft 9 can form the transmission output of the servo drive 1. However, the driven shaft 9 can also be connected to at least one further transmission element and / or at least one further transmission stage, which, for example, converts the rotational movement of the driven shaft 9 into a translational movement. In addition or as an alternative, at least one planetary stage can also be connected here.

[0095] like Figure 1 As shown, the drive train 2 according to the illustrated embodiment comprises a fourth transmission element 10. The fourth transmission element 10 is arranged downstream of the first transmission element 7 in the driven direction of the drive train 2. The fourth transmission element 10 can also preferably be a gear, in particular a spur gear. Figure 1 As shown, at least one fifth transmission element 11 is arranged downstream of the fourth transmission element 10. The fourth transmission element 10 and the fifth transmission element 11 are in direct mechanical operative connection and / or mesh with each other. The fifth transmission element 11 is connected to the driven shaft 9 in a rotationally fixed manner. The fifth transmission element 11 and the driven shaft 9 can be constructed as an integral part.

[0096] In an alternative embodiment not shown here, the actuating drive 1 can also be designed in such a way that the fourth transmission element 10 forms and / or is designed as the output shaft 9. In this case, the fourth transmission element 10 does not need to have a toothing.

[0097] Therefore, according to the present embodiment, the driving force generated by the driving motor 3 is transmitted to the first transmission element 7 via the electric pinion 6. The fourth transmission element 10 is connected to the first transmission element 7 in a rotationally fixed manner. The fourth transmission element 10 and the first transmission element 7 can be independent components connected in a rotationally fixed manner. Alternatively, these transmission elements can also be connected by integral molding. Therefore, the fourth transmission element 10 rotates with the first transmission element 7. The fourth transmission element 10 is engaged with the fifth transmission element 11, thereby transmitting the driving force to the driven shaft 9. The driven shaft is preferably connected to the fifth transmission element 11 in a rotationally fixed manner in the figure.

[0098] When there is a rotational force on the driven shaft 9 (for example, when the parking brake is activated), the drive gearbox 5 and the drive motor 3 will rotate as long as the drive motor 3 does not apply an opposing force. The reason for this is that the drive gearbox 5 is constructed as a non-self-locking type. Although the advantage of the non-self-locking drive gearbox 5 is high efficiency, the self-locking of the servo drive 1 is essential for many applications.

[0099] Based on this, according to Figure 1 The servo drive 1 of the illustrated embodiment includes a brake unit 12. The brake unit has a brake motor 13. The brake motor 13 is preferably an electric motor and / or includes a second motor shaft 14. The brake unit 12 also has a brake gearbox 15. The brake gearbox 15 is arranged downstream of the brake motor 13 and is connected to the brake motor 13. The brake gearbox 15 has at least one second transmission element 16 that is rotatably supported. The brake gearbox 15 also has a third transmission element 18 that is rotatably supported. The second transmission element 16 and the third transmission element 18 are connected to each other. Figure 1 In particular, directly (that is, without connecting another transmission element in the middle) is in mechanical operative connection. Therefore, these transmission elements preferably directly mesh and / or bite together.

[0100] The second transmission element 16 has a second toothing 20. The second toothing 20 of the second transmission element 16 is designed differently from the first toothing 8 of the first transmission element 7. Therefore, the first toothing 8 of the first transmission element 7 is preferably designed so that it does not form a self-locking in cooperation with another transmission element, in particular with the motor pinion 6. Therefore, the first toothing 8 of the first transmission element 7 can have, for example, helical teeth. The second toothing 20 of the second transmission element 16 is designed so that it forms a self-locking in cooperation with another transmission element, in particular with the third transmission element 18. For this purpose, the second toothing 20 is, for example, a worm gear. The third transmission element 18, in particular the worm 19, has a third toothing 21. The third toothing 21 corresponds to the second toothing 20 of the second transmission element 16, so that in cooperation, a self-locking of the brake gearbox 15 is formed.

[0101] In order to give the brake gearbox 15 a corresponding self-locking effect, the brake gearbox 15 advantageously comprises a worm gear or is designed as a worm gear. The worm gear has a worm 19 preferably on the drive side and a worm wheel 17 in particular on the output side. Figure 1In the embodiment shown, the second transmission element 16 is designed as a worm wheel 17. In addition, the third transmission element 18 is designed as a worm 19. However, the design can also be reversed. In this regard, the second transmission element 16 and the third transmission element 18 have corresponding tooth systems, namely a second tooth system 20 and a third tooth system 21, which together form a self-locking of the brake gearbox 15. In the process, the worm wheel 17, in particular with its second tooth system 20, directly meshes with the worm 19, in particular the third tooth system 21. According to Figure 1 The third transmission element 18 , in particular the worm 19 , is arranged in a rotationally fixed manner on the second motor shaft 14 of the brake motor 13 .

[0102] In order to enable the brake unit 12 to brake the drive train 2, the brake gearbox 15 is in mechanically active connection with the drive gearbox 5, in particular via a (preferably non-rotatable) interface. The interface is constructed between the first transmission element 7 of the drive gearbox 5 and the second transmission element 16 of the brake gearbox 15. For this purpose, the first transmission element 7 and the second transmission element 16 are arranged on a common rotation axis 22. Both the first transmission element 7 and the second transmission element 16 are supported in a manner that can rotate around the common rotation axis 22, in particular together. In order to transmit the self-locking effect and the braking force of the brake gearbox 15 to the drive gearbox 5, in particular when the drive motor 3 is disconnected, the second transmission element 16 is connected and / or coupled to the first transmission element 7 in a non-rotatable manner. The first transmission element 7 of the drive gearbox 5 and the second transmission element 16 of the brake gearbox 15 thus form an anti-rotation unit 23, which is supported in a manner that can rotate around the common rotation axis 22.

[0103] according to Figure 1 In the first embodiment shown, the first transmission element 7 and the second transmission element 16 are independent components, in particular gears, which are connected in a detachable and / or inseparable manner so that they rotate together as an anti-rotation unit 23. To this end, the first transmission element 7 and the second transmission element 16 can be connected in a form fit, a press fit and / or a material joint. The components of the anti-rotation unit 23 can be connected with or without a gap along the circumference of the common rotating shaft 22. In this way, for example, a gap can be formed between the first transmission element 7 and the second transmission element 16 connected thereto in an anti-rotation manner, so that these transmission elements can be twisted toward each other or relative to each other within the gap range along the circumference of the common rotating shaft 22. Therefore, relative twisting within the gap range is also understood as an anti-rotation connection. In this way, it is possible to prevent the first transmission element 7 and / or the second transmission element 16 from being damaged when the corresponding tooth surfaces of the first transmission element 7 and the second transmission element 16 are close to each other, when the drive motor 3 and the brake motor 13 are started asynchronously and / or staggered in time. In addition, the locking between the second transmission element 16 and the third transmission element 18 can be released with a small force using the correspondingly constructed gap.

[0104] Now, if in normal use, when the drive motor 3 is stopped, there is a rotational force on the driven shaft 9 that may cause the drive gearbox 5 and the first motor shaft 4 to rotate, then this rotational force will also act on the brake gearbox 15 based on the anti-rotation connection between the first transmission element 7 and the second transmission element 16. Now, since the brake gearbox 15 is constructed as a self-locking type based on the tooth system between the second transmission element 16 and the third transmission element 18, this rotational force is offset by the braking force transmitted to the first transmission element 7 via the interface or anti-rotation connection between the first transmission element 7 and the second transmission element 16. Thereby, the drive gearbox 5 is prevented from rotating.

[0105] according to Figure 1 , just like the first transmission element 7 and the second transmission element 16, the fourth transmission element 10 is rotatably arranged on the common rotation shaft 22. In this regard, the first transmission element 7, the second transmission element 16 and / or the fourth transmission element 10 are particularly arranged coaxially relative to the common rotation shaft 22. The first transmission element 7 is arranged between the second transmission element 16 and the fourth transmission element 10 along the axial direction of the common rotation shaft 22. Figure 1 In the illustrated embodiment, the fourth transmission element 10 is an independent component and is, in particular, connected to the first transmission element 7 in a rotationally fixed manner in a detachable or inseparable manner. The connection between the first transmission element 7 and the fourth transmission element 10 can be constructed as a form fit, a press fit and / or a material joint. In addition, a gap can be formed between the first transmission element 7 and the fourth transmission element 10 along the circumference of the common rotation axis 22, so that these transmission elements can be twisted in the circumferential direction within the gap. Therefore, according to Figure 1 In the embodiment shown, the fourth transmission element 10 is a component of the anti-rotation unit 23. In an embodiment not shown here, the first transmission element 7 and the fourth transmission element 10 can also be constructed as one piece. Alternatively, the first transmission element 7 and the second transmission element 16 can also be constructed as one piece.

[0106] The rotationally fixed connection between the first transmission element 7 and the second transmission element 16 and / or the rotationally fixed connection between the first transmission element 7 and the fourth transmission element 10 can be formed in particular by a preferably play-free or play-free keyway connection. The keyway connection can be formed directly between the aforementioned components or indirectly via another component, such as a shaft.

[0107] like Figure 1As shown, the anti-rotation unit 23 is accommodated and / or rotatably supported in the first bearing area 24 and / or the second bearing area 25, so that it can rotate around the common rotation axis 22. The servo drive 1 includes a housing 28. The first bearing area 24 and / or the second bearing area 25 are constructed in the housing 28. In addition or as an alternative, the servo drive 1 can have a support element not shown here, in particular a carrier plate, which is arranged in the housing 28. At least one of the bearing areas 24, 25 can also be constructed on or in the support element. In addition, individual components of the drive train 2 and / or the brake unit 12 can be arranged on and / or supported in the support element.

[0108] according to Figure 1 In the embodiment shown, the anti-rotation unit 23 is supported in at least one of the bearing regions 24, 25 in a particularly rotatable manner via at least one bearing element 26, 27. The at least one bearing element 26, 27 can also be connected to the anti-rotation unit 23 in a rotationally fixed manner. The at least one bearing element 26, 27 can also be constructed integrally with the anti-rotation unit 23. The bearing elements 26, 27 are constructed here as bearing pins, which are rotatably accommodated in correspondingly constructed bearing regions 24, 25 of the housing 28.

[0109] The brake motor 13 is designed to be smaller than the drive motor 3. In addition or as an alternative, the brake motor 13 can have a lower electrical power. This allows the servo drive 1 to be designed to be extremely compact and space-saving. In normal use, blocking can occur in the brake gearbox 15. In the process, the tooth flanks 33, 35 of the second transmission element 16, in particular the worm wheel 17, are wedged together with the tooth flanks 34, 36 of the third transmission element 18, in particular the worm 19. The brake motor 13 can be designed to be so small and / or have such a low electrical power that in normal use it cannot unlock the brake gearbox 15 alone, but only with the assistance of the drive motor 3.

[0110] from Figure 1 It can be seen from the embodiment shown that the first motor shaft 4 of the drive motor 3 is parallel to the common rotation shaft 22. In addition, the second motor shaft 14 of the brake motor 13 is parallel to the common rotation shaft 22.

[0111] To control the drive motor 3 and the brake motor 13, the servo drive 1 includes a control unit 29. The drive motor 3, the drive gearbox 5, the brake motor 13, the brake gearbox 15 and / or the control unit 29 can be arranged and / or integrated in the housing 28 in whole or in part. Alternatively, the control unit 29 can also be constructed as a component independent of the housing 28 and / or partially separated from the housing. The control unit 29 is electrically connected to the drive motor 3 via a first wire 30. In addition, the brake motor 13 is electrically connected to the control unit 29 via a second wire 31. The first wire 30 and the second wire 31 are separated from each other. The control unit 29 can drive the drive motor 3 and the brake motor 13 to start separately and / or independently of each other, in particular asynchronously and / or staggered in time.

[0112] according to Figure 1 , the brake unit 12 comprises at least one sensor 32. The sensor 32 is arranged in the region of the brake motor 13 and / or in the brake motor. The sensor 32 is preferably a rotational angle sensor and / or an end position sensor. The sensor 32 and / or the control unit 29 are designed in such a way that the relative position between the second gearing 20 of the second transmission element 16 and the third gearing 21 of the third transmission element 18 can be determined indirectly or directly by means of the sensor 32. Additionally or alternatively, the sensor 32 and / or the control unit 29 are designed in such a way that a blocking of the brake gearbox 15 can be detected. In normal use, a blocking can occur between the second transmission element 16 and the third transmission element 18, in particular when the tooth flanks of the second gearing 20 are wedged together with the tooth flanks of the third gearing 21.

[0113] According to one embodiment, the position and / or positioning of the second transmission element 16 and / or the third transmission element 18 within, in particular, the maximum adjustment range (within which the transmission elements 16, 18 can be adjusted) can be determined by the control unit 29 and / or at least one sensor 32. Thus, the second transmission element 16 and / or the third transmission element 18 can be adjusted between two end stops, which each form an end point of the adjustment range. The position within this adjustment range can be determined by the sensor 32. In addition, at least one start mode range can be saved for the second transmission element 16 and / or for the third transmission element 18. The at least one start mode range forms a subrange of the adjustment range. The start mode range is selected here in such a way that the probability of blocking is greatly increased when the second transmission element 16 and / or the third transmission element 18 stops within this start mode range and / or when the direction of rotation of the servo drive 1 is reversed in this position. If the event described here occurs, the control unit 29 can be designed so that it controls the start of the drive motor 3 and / or the brake motor 13 in such a way that blocking is prevented and / or a blocking that has occurred is released. Which modes and / or control programs are suitable for this will be explained in detail below.

[0114] However, the servo drive 1 can also be designed in such a way that it can detect a blocking without using the at least one sensor 32. In order to be able to detect a blocking of the brake gearbox 15 and / or the presence or a position of the brake gearbox 15 at which the probability of a blocking is high even without the sensor 32, a current limit value of the drive motor 3 and / or the brake motor 13 can be stored in the control unit 29. The control unit 29 recognizes that there is a high probability of a blocking if the current limit value is exceeded immediately after starting, immediately after a reversal of the direction of rotation, and / or immediately before the last shutdown.

[0115] As mentioned above, Figure 2 A schematic diagram of a second embodiment of the servo drive 1 is shown. Figure 2 In the description of the alternative embodiment shown, compared to Figure 1 The features with the same technical solutions and / or working principles as the first embodiment shown use the same reference numerals. Unless otherwise specified, the technical solutions and / or working modes thereof are the same as those of the features described above.

[0116] Figure 2 The second embodiment shown is Figure 1 The difference from the first embodiment shown lies essentially in the arrangement of the brake motor 13 and / or the third transmission element 18, in particular the worm 19, relative to the anti-rotation unit 23. The rotation axis of the second motor shaft 14 and / or the third transmission element 18 is thus oriented obliquely, in particular perpendicularly, to the common rotation axis 22 of the anti-rotation unit 23. Furthermore, the third transmission element 18 is located below the second transmission element 16 in the figure.

[0117] Another difference lies in the design of the anti-rotation unit 23. Figure 2 In the embodiment shown, the structure is one-piece, in particular formed from a single piece of material. In this respect, no gap is formed between the first transmission element 7 and the second transmission element 16. This also applies to the single-piece material connection between the first transmission element 7 and the fourth transmission element 10. Figure 1 In the embodiment of the servo drive 1 shown, the anti-rotation unit 23 can also be constructed as an integral part, in particular, formed of a whole material. Figure 1 Shown and Figure 2 In the embodiment shown, all can be constructed as an integrated double gear and / or three gears. In addition, the third transmission element 18 and the brake motor 13 are Figure 1 In the embodiment shown, Figure 2 The arrangement is identical in the illustrated embodiment.

[0118] The following describes the control unit 29 for operation, in particular according to Figure 1 and / or Figure 2The working mode of the servo drive 1 is explained. The servo drive 1 can be constructed according to the above description, wherein the features mentioned can be applied individually or in any combination.

[0119] To implement at least one subsequent working process, the servo drive 1 includes a drive train 2. The drive train 2 includes a drive gearbox 5. The drive gearbox 5 is designed to be non-self-locking. The drive gearbox 5 also has a drive motor 3 for driving the drive gearbox 5. In addition, the servo drive 1 includes a brake unit 12 for braking the drive train 2. The brake unit 12 includes a self-locking brake gearbox 15, which is in mechanical operative connection with the drive gearbox 5. Through the mechanical operative connection, when the drive motor 3 is not energized, the brake gearbox 15 can achieve braking of the drive gearbox 5 and the drive motor 3. The brake unit 12 also has a brake motor 13 for driving the brake gearbox 15. The servo drive 1 also has a control unit 29 for controlling the drive motor 3 and the brake motor 13. The control unit 29 is designed in such a way that the drive motor 3 and the brake motor 13 can be operated asynchronously and / or staggered in time, especially in a starting mode. The drive motor 3 and the brake motor 13 can be controlled by the control unit 29 in such a way that blocking in the brake gearbox 15 is prevented and / or released. The advantage is that the brake motor 13 can be designed to be extremely small and low-power, which in turn can reduce the structural volume of the actuating drive 1 and reduce the production costs.

[0120] The control unit 29 is constructed in such a way that the drive motor 3 and the brake motor 13 can be driven by the control unit 29 in particular to adjust the structural unit in normal mode. In normal mode, the control unit 29 synchronously controls the start of the drive motor 3 and the brake motor 13. As a result, the third transmission element 18 and the anti-rotation unit 23 move synchronously toward each other. Therefore, the first tooth surface 34 of the third transmission element 18 leads the first tooth surface 33 of the second transmission element 16. In addition, in this case, the second tooth surface 36 of the third transmission element 18 follows the corresponding second tooth surface 35 of the second transmission element 16. Therefore, the corresponding tooth surfaces 33, 34, 35, 36 are spaced apart from each other in normal mode. This advantageously avoids friction losses between the anti-rotation unit 23 and the third transmission element 18, thereby improving the efficiency of the servo drive 1.

[0121] In addition, the control unit 29 is constructed in such a way that the drive motor 3 and the brake motor 13 can be operated in at least one starting mode for avoiding and / or releasing the blocking of the brake gearbox 15, especially when the servo drive 1 is restarted after stopping and / or when the rotation direction of the servo drive 1 is reversed. In this at least one starting mode, the drive motor 3 and the brake motor 13 are controlled to start synchronously, asynchronously, simultaneously and / or staggered in time with each other by the control unit 29.

[0122] Figure 3a , Figure 3b , Figure 3c Schematic cross-sectional views showing the second transmission element 16 of the anti-rotation unit 23 of the servo drive 1 and the third transmission element 18 of the brake gearbox 15 at different time points during the first starting mode. The servo drive 1 can be operated according to Figure 1 and / or Figure 2 The servo drive 1 shown is constructed in a manner such that the corresponding features may be present individually or in any desired combination.

[0123] exist Figure 3a In the embodiment of the present invention, the first tooth flank 33 of the second transmission element 16 of the anti-rotation unit 23 abuts against the first tooth flank 34 of the third transmission element 18. In this case, a lock may be formed between the two first tooth flanks 33, 34. However, it is also reasonable to carry out the first starting mode when the spacing between the two tooth flanks 33, 34 is small.

[0124] To release and / or prevent this blocking, in the first starting mode, the control unit 29 first controls the brake motor 13 to start and / or energize it, and then the drive motor 3. Figure 3b The first rotation direction 37 of the third transmission element 18 shown by the arrow in FIG. 1 is implemented. Thereby, the first tooth surface 34 of the third transmission element 18 leaves the first tooth surface 33 of the second transmission element 16. Its technical effect is that locking is released and / or prevented by controlling the start.

[0125] according to Figure 3c After the first time period, the control unit 29 also controls the drive motor 3 to start and / or energize it. The first time period is determined and / or determined by the control unit 29 in such a way that the second transmission element 16 starts to rotate before the second tooth flank 36 of the third transmission element 18 collides with the second tooth flank 35 of the second transmission element 16. The start is controlled in such a way that the anti-rotation unit 23 or the second transmission element 16 starts to rotate. Figure 3c As shown by another arrow in the figure, the first gear element 16 moves in the first rotation direction 39 of the second gear element 16. As a result, the first tooth flank 33 of the second gear element 16 follows the first tooth flank 34 of the third gear element 18. Since the third gear element 18 moves further in its first rotation direction 37, the first start mode now smoothly transitions to the normal mode already described above.

[0126] Figure 4a , Figure 4b , Figure 4c Schematic cross-sectional views showing the second transmission element 16 of the anti-rotation unit 23 of the servo drive 1 and the third transmission element 18 of the brake gearbox 15 at different points in time during the second starting mode. Figure 4aIn the embodiment of the present invention, the first tooth flank 33 of the second transmission element 16 of the anti-rotation unit 23 abuts against the first tooth flank 34 of the third transmission element 18. In this case, as described above, a lock may be formed between the two first tooth flanks 33, 34. However, it is also reasonable to carry out the second starting mode when the spacing between the two tooth flanks 33, 34 is small.

[0127] To release and / or prevent this blocking, in the second starting mode, the control unit 29 first controls the drive motor 3 to start and / or energize it, and then the brake motor 13. Figure 4b The second rotation direction 40 of the second transmission element 16 indicated by the arrow in FIG. is implemented. Thereby, the first tooth flank 33 of the second transmission element 16 leaves the first tooth flank 34 of the third transmission element 18. As a result, blocking is released and / or prevented by controlling the activation.

[0128] according to Figure 4c After the second time period, the control unit 29 also controls the brake motor 13 to start and / or energize it. The first and second time periods can be the same or different. The second time period is determined and / or determined by the control unit 29 in such a way that the third transmission element 18 starts to rotate before the second tooth surface 35 of the second transmission element 16 collides with the second tooth surface 36 of the third transmission element 18. The start is controlled in such a way that the third transmission element 18 starts to rotate as shown in FIG. Figure 4c As shown by another arrow in the figure, the third transmission element 18 moves in the second rotation direction 38. As a result, the first tooth flank 34 of the third transmission element 18 follows the outgoing first tooth flank 33 of the second transmission element 16. As the second transmission element 16 moves further in its second rotation direction 40, the second start mode now smoothly transitions to the normal mode already described above.

[0129] Figure 5a , Figure 5b , Figure 5c Schematic sectional views of the second transmission element 16, the anti-rotation unit 23 and the third transmission element 18 of the brake gearbox 15 of the servo drive 1 at different points in time during the alternative second starting mode. Figure 5a In the embodiment of the present invention, the first tooth flank 33 of the second transmission element 16 of the anti-rotation unit 23 abuts against the first tooth flank 34 of the third transmission element 18. In this case, as described above, a locking may be formed between the two first tooth flanks 33, 34. However, it is also reasonable to carry out an alternative second starting mode when the spacing between the two tooth flanks 33, 34 is small.

[0130] To release and / or prevent this blocking, the control unit 29 first Figure 5a , Figure 5b , Figure 5c The alternative second startup mode and Figure 4a , Figure 4b , Figure 4c The first variant of the second starting mode shown controls the drive motor 3 to start. Only then does the brake motor 13 start and / or energize it. Figure 5b as well as Figure 4b The second rotation direction 40 of the second transmission element 16 indicated by the arrow in FIG. 1 is implemented. As a result, the first tooth flank 33 of the second transmission element 16 leaves the first tooth flank 34 of the third transmission element 18. Thus, blocking is released and / or prevented.

[0131] Different from Figure 4a , Figure 4b , Figure 4c The sequence of the second startup mode shown is based on Figure 5c After the third time period, the drive motor 3 is started and / or energized in such a way that the rotation direction of the second transmission element 16 and / or the rotation direction of the anti-rotation unit 23 is reversed. The third time period is the same as or shorter than the second time period. In addition or as an alternative, the third time period is selected in such a way that the rotation direction is reversed before the second tooth flank 35 of the second transmission element 16 collides with the second tooth flank 36 of the third transmission element 18.

[0132] according to Figure 5c , at the same time as or after the reversal of the rotation direction of the second transmission element 16, that is, after the second time period, the control unit 29 also controls the brake motor 13 to start and / or energize it. The second and third time periods can be the same or different, wherein preferably the length of the second time period is greater than the third time period. The second time period is determined and / or determined by the control unit 29 in such a way that the third transmission element 18 starts to rotate before the first tooth surface 33 of the second transmission element 16 collides with the first tooth surface 34 of the third transmission element 18. The start is controlled in such a way that the third transmission element 18 starts to rotate as shown in FIG. Figure 5c As shown by another arrow in the figure, the third transmission element 18 moves in the first rotational direction 37. As a result, the first tooth flank 34 of the third transmission element 18 leads the first tooth flank 33 of the second transmission element 16. In addition, the second tooth flank 36 of the third transmission element 18 follows the second tooth flank 35 of the second transmission element 16. Since the second transmission element 16 moves further in its first rotational direction 39, the second start mode now smoothly transitions to the normal mode described above even in the case of a controlled start.

[0133] In the case where the second tooth flank 35 of the second transmission element 16 abuts against the second tooth flank 36 of the third transmission element 18 or is arranged in close proximity thereto, so that a lock-up or a high probability of a lock-up between these tooth flanks would occur if the start-up were also in normal mode, Figure 3a , Figure 3b , Figure 3c The first startup mode shown, Figure 4a , Figure 4b , Figure 4c The second startup mode and / or Figure 5a , Figure 5b , Figure 5c The second starting mode shown can also be started in a similar manner in the opposite direction of rotation.

[0134] Furthermore, advantageously, first executing Figure 3a , Figure 3b , Figure 3c The first startup mode is shown, and it is executed only if the first startup mode is unsuccessful Figure 4a , Figure 4b , Figure 4c and / or Figure 5a , Figure 5b , Figure 5c The second startup mode is shown. Alternatively, it can also be performed in reverse.

[0135] To prevent and / or release the locking of the brake gearbox 15, in particular when restarting after stopping and / or when the direction of rotation of the servo drive 1 is reversed, the first and / or second start-up mode preferably described in the foregoing is executed. If the first start-up mode is executed first, the second start-up mode can also be executed subsequently. It is also possible to execute the second start-up mode first and then the first start-up mode. It is also advantageous that at least one of the start-up modes is executed only when at least one current limit value is exceeded, in particular immediately after starting, immediately after the direction of rotation is reversed and / or immediately before the last stop. The term "immediately" in the context of this article refers to a defined time period, which is in particular shorter than two seconds. In addition or alternatively, it is advantageous that at least one start-up mode is executed only when the sensor 32 indirectly or directly detects a lock and / or the determined lock possibility is extremely high. As mentioned above, this may be the case when the actual position of the second transmission element 16 and / or the third transmission element 18 is within the range of the start-up mode stored in the control unit 29.

[0136] Reference numerals list

[0137] 1 Servo drive

[0138] 2 Drive system

[0139] 3. Drive Motor

[0140] 4 First motor shaft

[0141] 5 Drive gearbox

[0142] 6 Electric pinion

[0143] 7 First transmission element

[0144] 8 First tooth system

[0145] 9 Driven shaft

[0146] 10 Fourth transmission element

[0147] 11 Fifth transmission element

[0148] 12 Braking unit

[0149] 13 Brake motor

[0150] 14 Second motor shaft

[0151] 15 Brake gear box

[0152] 16 Second transmission element

[0153] 17 Worm gear

[0154] 18 Third transmission element

[0155] 19 Worm

[0156] 20 Second tooth system

[0157] 21 Third tooth system

[0158] 22 Shared shaft

[0159] 23 Anti-rotation unit

[0160] 24 First bearing area

[0161] 25 Second bearing area

[0162] 26 First bearing element

[0163] 27 Second bearing element

[0164] 28 Shell

[0165] 29 Control Unit

[0166] 30 First Wire

[0167] 31 Second Wire

[0168] 32 Sensors

[0169] 33 First tooth surface of the second transmission element

[0170] 34 The first tooth surface of the third transmission element

[0171] 35 The second tooth surface of the second transmission element

[0172] 36 The second tooth surface of the third transmission element

[0173] 37 First rotation direction of the third transmission element

[0174] 38 Second rotation direction of the third transmission element

[0175] 39 First rotation direction of the second transmission element

[0176] 40 Second rotation direction of the second transmission element

Claims

1. A servo drive (1) for an electrical structural unit of a vehicle, the servo drive (1) having Drive system (2), The drive system (2) comprises a drive gear box (5) and a drive motor (3) for driving the drive gear box (5); a brake unit (12) for braking the drive train (2), The brake unit (12) comprises a self-locking brake gearbox (15) operatively connected to the drive gearbox (5), and a brake motor (13) for driving the brake gearbox (15); as well as A control unit (29) for controlling the drive motor (3) and the brake motor (13), characterized in that: The control unit (29) is designed in such a way that the drive motor (3) and the brake motor (13) can be operated asynchronously and / or with a time offset, in particular in a starting mode.

2. The servo drive according to claim 1, characterized in that The control unit (29) is designed in such a way that the drive motor (3) and the brake motor (13) can be operated synchronously and / or simultaneously, in particular in normal mode.

3. The servo drive according to any one of the preceding claims, characterized in that The first transmission element (7), the second transmission element (16) and / or the fourth transmission element (10) are jointly constructed as an anti-rotation unit (23), and / or the anti-rotation unit (23) is supported in a manner that allows rotation about a common rotation axis (22).

4. A servo drive according to any one of the preceding claims, characterized in that Compared to the drive motor (3), the brake motor (13) is smaller and / or has a lower electrical power.

5. The servo drive according to any one of the preceding claims, characterized in that The control unit (29) is designed in such a way that the drive motor (3) and the brake motor (13) can first be operated in at least one of the starting modes when restarting after a shutdown and / or when the rotation direction of the servo drive (1) is reversed, and / or in particular can then be used to adjust the normal mode operation of the structural unit.

6. A servo drive according to any one of the preceding claims, characterized in that The control unit (29) is designed so that it operates the brake motor (13) in the normal mode so that the first tooth surface (34) of the third transmission element (18) of the brake gearbox (15) leads the corresponding first tooth surface (33) of the second transmission element (16), in particular by a certain distance, and / or the second tooth surface (36) of the third transmission element (18) follows the corresponding second tooth surface (35) of the second transmission element (16), in particular by a certain distance.

7. A servo drive according to any one of the preceding claims, characterized in that The control unit (29) is designed in such a way that it first energizes the brake motor (13) in a first starting mode for avoiding and / or releasing a blocking of the brake gearbox (15) and only energizes the drive motor (3) in particular after a first time period which is in particular stored in the control unit (29) or determined by the control unit (29).

8. A servo drive according to any one of the preceding claims, characterized in that Firstly, the brake motor (13) is energized in the first starting mode in such a way that The third transmission element (18) is caused to rotate along a rotation direction (37) corresponding to the planned adjustment movement of the servo drive (1), so that the tooth surface (34, 36) of the third transmission element (18) which is preferably adjacent to or in contact with the corresponding tooth surface (33, 35) of the second transmission element (16) leaves the corresponding tooth surface (33, 35) of the second transmission element (16).

9. The servo drive according to any one of the preceding claims, characterized in that After the first time period, the drive motor (3) is energized in the first starting mode in such a way that The second transmission element (16) is caused to rotate in a rotation direction (39) corresponding to the planned adjustment movement of the servo drive (1), so that the tooth surface (33) of the second transmission element (16) follows the corresponding tooth surface (34) of the third transmission element (18) that is leaving.

10. The servo drive according to any one of the preceding claims, characterized in that The first time period is determined and / or is determined by the control unit (29) in such a way that the second transmission element (16) begins to rotate before the other tooth flank (36) of the third transmission element (18) that has moved forward collides with the corresponding tooth flank (35) of the second transmission element (16).

11. The servo drive according to any one of the preceding claims, characterized in that The control unit (29) is designed in such a way that it first energizes the drive motor (3) in a second starting mode for preventing and / or releasing a blocking of the brake gearbox (15). The brake motor (13) is additionally energized only after a second time period, which is in particular stored in the control unit (29) or determined by the control unit (29), and / or The rotation direction of the drive motor (3) is reversed simultaneously with or after the brake motor (13) is energized.

12. A servo drive according to any one of the preceding claims, characterized in that First, the drive motor (3) is energized in the second starting mode in this way: causing the second transmission element (16) to rotate in a rotation direction (39, 40) corresponding to or opposite to the planned adjustment movement of the servo drive (1), As a result, the tooth surface (33) of the second transmission element (16) adjacent to or in contact with the corresponding tooth surface (34) of the third transmission element (18) is separated from the corresponding tooth surface (34) of the third transmission element (18).

13. A servo drive according to any one of the preceding claims, characterized in that Subsequently, when the second transmission element (16) rotates in a rotational direction (40) opposite to the planned adjustment movement of the servo drive (1), the drive motor (3) is energized in the second starting mode in such a way that its rotational direction is reversed, so that the second transmission element (16) rotates in a rotational direction (39) corresponding to the planned adjustment movement of the servo drive (1).

14. A servo drive according to any one of the preceding claims, characterized in that After the second time period, the brake motor (13) is energized in the second mode in such a way that the third transmission element (18) rotates in a rotational direction (37, 38) corresponding to the planned adjustment movement of the servo drive (1), so that the tooth flank (34, 36) of the third transmission element (18) follows the corresponding tooth flank (33, 35) of the second transmission element (16).

15. A servo drive according to any one of the preceding claims, characterized in that The second time period is determined and / or is determined by the control unit (29) in such a way that the third transmission element (18) begins to rotate before the other tooth flank (35) of the second transmission element (16) that has moved forward collides with the corresponding tooth flank (36) of the third transmission element (18).

Images