Device for operating electric motor for steering-by-wire system, electric drive for steering-by-wire system of motor vehicle, control device and steering-by-wire system

Abstract

The utility model relates to a device (105) for operating an electric motor for a steering-by-wire system, an electric drive for a steering-by-wire system of a motor vehicle, a control device and a steering-by-wire system. The device comprises a steering device (200) and a control unit (205) external to the steering device (200). The steering device (200) comprises a control device (210) and a sensor device (215). The sensor device (215) is configured to provide at least one sensor signal (230) which represents a position of a part of the electric machine and / or a position of an adjusting element of the steering device (200). The external control unit (205) is configured to evaluate a position of a portion of the motor and / or a position of an adjusting element (102, 650, 706) of the steering device (200) in response to the at least one sensor signal (230) and to provide a deactivation signal (235) to the control device (210) to deactivate the motor when the sensor signal (230) satisfies a deactivation criterion.

Description

Technical Field

[0001] The present invention relates to an apparatus and method for operating an electric motor, an electric drive for a steer-by-wire system, a control device, and a steer-by-wire system. Background Technology

[0002] The steer-by-wire system is preferably configured as a rear axle steering system, which has complex electronic components due to its very high safety requirements. The steer-by-wire system can have a central actuator with an electric motor drive, allowing both wheels on the axle to be steered simultaneously. Alternatively, the steer-by-wire system can have two actuators, such that the wheel steering angle of each wheel on the axle is set by a separate actuator. Using two actuators, it is possible to simultaneously adjust both wheels on the axle. Here, each actuator can have its own controller. Such an actuator is known, for example, from document DE3728592 A1. Summary of the Invention

[0003] In this context, according to the independent claims, the present invention provides improved apparatus and methods for operating an electric motor, improved electric drive for a steer-by-wire system, and improved motor vehicle. Advantageous designs are derived from the dependent claims and the description below.

[0004] The advantages that can be achieved using the solution proposed in this application are particularly that a device is provided that can reliably and quickly deactivate the motor in the steer-by-wire system of a motor vehicle when the vehicle is in a safety-critical mode.

[0005] A device for operating a motor for a vehicle's steer-by-wire system, particularly a rear axle steering system, has an actuator and a control unit located external to the actuator. The actuator includes power electronics and a sensor device. The sensor device is configured to provide at least one sensor signal indicating the position of a portion of the motor and / or the position of an adjusting element of the steering mechanism. The external control unit is configured to assess the position of the portion of the motor and / or the position of the adjusting element of the steering mechanism in response to the at least one sensor signal, and to provide a deactivation signal to a control device to deactivate the motor when the sensor signal meets a deactivation criterion.

[0006] The motor vehicle may be, for example, an electrically driven motor vehicle, such as a passenger vehicle, a truck, a bus, etc. The motor may drive the steering device in the form of an electric motor. The control device may be configured as a microcontroller and receive and output signals. A control unit located outside the steer-by-wire system or steering mechanism may be configured as a higher-level controller. The deactivation criteria may indicate, for example, excessive speed, acceleration in the longitudinal and / or lateral directions, the position of the adjusting element (e.g., the lead screw nut or lead screw or steering tie rod of a linear actuator) exceeding tolerance, and / or inconsistency in the positions of the two actuators. It is also conceivable that when a stepper motor is used as the motor, the position of the rotor, which is part of the motor, can be monitored, thereby identifying, for example, the deviation of the actual position of the rotor from the desired or required target position and sending a deactivation signal accordingly. The proposed solution can also be understood as a steer-by-wire system, particularly a rear axle steering system designed with external safety monitoring. In this case, the safety function is decoupled from the steer-by-wire system or steering mechanism, thereby providing a safe path outside the steering mechanism.

[0007] The solutions proposed in this application can reduce costs and enable user-independent software and / or hardware. Simple and inexpensive electronics can be implemented. This can be achieved, for example, by actuators with little or no electronics (e.g., power electronics) for operating the drive motor. For functional or operational purposes, these actuators may only have a higher-level controller, i.e., a control unit located outside the steer-by-wire system or steering device in the motor vehicle, particularly as a central controller for operating various actuators in the vehicle chassis.

[0008] To provide sensor signals, the sensor device may have at least one rotor position sensor and may additionally or alternatively have a linear displacement sensor. For actuators in steering systems, particularly rear axle steering systems, the linear displacement sensor is used to verify the reliability of the lead screw position when the rotor position sensor of the electric motor cannot adequately determine the position (e.g., when the rotor position sensor is off or de-energized). In contrast, the rotor position sensor is, for example, integrated into the electric motor. This electric motor specifically drives the lead screw nut of the lead screw driver via a toothed belt drive. Rotation of the lead screw nut causes linear or translational displacement of the lead screw. The displacement of the lead screw in the actuator housing is determined by the rotor position sensor, specifically by calculating the position based on the change in rotor position. This allows the determination of the set steering angle. The linear displacement sensor is used to verify reliability, for example, in situations where the toothed belt may skip or the power supply may be interrupted (e.g., when the vehicle is parked and the wheels are turning). Therefore, for example, the position of the lead screw in the actuator needs to be detected. This allows for reliable and rapid detection of the position of a portion of the motor or the position of the steering system's adjusting elements. Furthermore, sensors can be manufactured at low cost and installed in sensor devices in a space-saving manner.

[0009] The sensor device can be configured to provide a sensor signal when a portion of the motor or a portion of the steering mechanism's adjustment element is in a deactivated range.

[0010] The control unit can be configured to provide a preset signal, different from a deactivation signal, to the control device in response to at least one sensor signal. Here, the preset signal may represent a target value for the position of a portion of the motor and / or the position of an adjusting element of the steering mechanism. Therefore, the motor will not deactivate.

[0011] When the position of a portion of the motor and / or the position of the steering mechanism's adjusting element deviates from the position of the motor portion indicated by a preset signal and / or the position of the steering mechanism's adjusting element beyond the tolerance range, the control unit may output a stop signal. The position may, for example, be an inconsistent position of two actuators or an adjusting element position outside the allowable tolerance range.

[0012] If a vehicle is determined to be in an unsafe condition, for example due to signals from the actuators of the steer-by-wire system (particularly the rear axle steering system) or signals existing within the vehicle itself, the control unit can issue a deactivation signal. Because the motor is deactivated due to the unsafe condition, the driver, passengers, and other road users can be protected from injury in an accident. Since the motor drives the actuators of the steer-by-wire system, changes in steering motion can be achieved. Here, the actuators of the rear axle steering system are adjusted based on parameters such as speed, acceleration, lateral forces in the chassis, and steering angles at the front and rear axles. This adjustment is calculated in the controller, which then sends control signals to the actuators. Particularly important in this relationship is that the higher the vehicle speed, the smaller the wheel steering angle or the adjustment of the wheel steering angle should be (at very slow speeds and during parking, the adjustment or steering angle is, for example, at most 10°, while at speeds exceeding 50 km / h, only a few arcminutes or arcseconds are adjusted). If the actuator's motor or adjusting element is monitored accordingly, safety can be significantly improved because if an error occurs at high speeds, a dangerous steering motion will not be performed.

[0013] The sensor device can be configured to provide at least one sensor signal using an ASIL-D-based safety system. ASIL stands for Automotive Safety Integrity Level and describes the safety requirement level of safety-related systems in a motor vehicle. In the embodiments described herein, Automotive Safety Integrity Level D is discussed, where D represents the highest safety requirement level. In this way, reliable safety functions conforming to predefined standards can be achieved.

[0014] According to another aspect of the invention, a method for operating an embodiment of the device proposed in this application includes the step of providing at least one sensor signal. Here, the sensor signal indicates the position of a motor and / or the position of an adjusting element of a steering device. The method further includes the step of providing a deactivation signal to deactivate the motor in response to the at least one sensor signal. Such an implementation can also very effectively achieve the advantages of the scheme described in this application. Any method steps are not limited to the order shown in the embodiments.

[0015] Furthermore, the present invention relates to an electric drive for a steer-by-wire system for motor vehicles, the electric drive having at least one motor, actuator, and adjusting element for the steering mechanism.

[0016] Furthermore, the present invention relates to a steer-by-wire system having an embodiment of the electric drive proposed in this application.

[0017] Furthermore, the present invention relates to a control device for operating the methods mentioned above. The control device (also referred to as a controller) can be understood herein as an electrical instrument that processes sensor signals and outputs control signals, switching signals, and / or data signals based on the sensor signals. The controller may have an interface that can be constructed in hardware and / or software. When constructed in hardware, the interface may, for example, be part of a so-called system ASIC that contains various functions of the controller. However, these interfaces may also be separate integrated circuits or at least partially composed of discrete components. When constructed in software, these interfaces may be software modules that exist, for example, on a microcontroller along with other software modules.

[0018] A motor vehicle characterized in that an electric actuator is used in a steer-by-wire system as described. Attached Figure Description

[0019] The invention will be explained in more detail by way of example with reference to the accompanying drawings.

[0020] Figure 1 An illustration of a vehicle axle for an embodiment of a motor vehicle is shown;

[0021] Figure 2 A block diagram of an embodiment of a device for a steer-by-wire system is shown;

[0022] Figure 3 A flowchart illustrating an embodiment of a method for operating a device is shown;

[0023] Figure 4 A schematic diagram of an embodiment of a motor vehicle is shown;

[0024] Figure 5 A schematic diagram of the actuator is shown;

[0025] Figure 6 A schematic diagram of an actuator for an embodiment of a steer-by-wire system for a motor vehicle is shown;

[0026] Figure 7 A schematic diagram of an embodiment of the vehicle is shown. Detailed Implementation

[0027] In the following description of preferred embodiments of the invention, the same or similar reference numerals are used for elements that have similar functions shown in the figures, and repeated descriptions of these elements are omitted here.

[0028] Figure 1 An illustration of a vehicle axle 1 for an embodiment of a motor vehicle 100 is shown.

[0029] The vehicle axle 1 is shown here as a rear axle with a subframe 2, which is fixed to or forms part of the vehicle frame and is connected to the body of the motor vehicle 100. However, the proposed solution is not limited to the rear axle. Each pair of wheels 5 and 6 is hinged to the subframe 2 via a link 3. The link 3 is part of the wheel suspension for wheels 5 and 6. An actuator 10 for a steer-by-wire system 12 is arranged on the subframe 2. The actuator 10 is fixed to the subframe 2 via its housing 21. In the current embodiment, the actuator 10, as a central actuator, has a through-type steering tie rod 27 that passes through the housing 21 of the actuator 10. A motor 22, also referred to as a drive motor, is arranged parallel to the axis of the steering tie rod 27. Crossbars 23 are hinged at the ends of the steering tie rods 27, and these crossbars are hinged to wheel supports (not shown) of wheels 5 and 6 respectively at ends opposite to the actuator 10. Obviously, as the axial displacement, i.e., the displacement of the steering tie rod 27 along the longitudinal axis in one direction or the other, changes the wheel steering angles 8 and 9. This is due to the forced connection formed by the tie rod 23 between the wheels 5 and 6 or the wheel carrier and the steering tie rod 27. To enable the wheels 5 and 6 to steer, these wheels are rotatably hinged to the wheel suspension 3 about their vertical axis. In other words, the actuator 10 is the device that enables the operation of the steering system 12. The actuator 10 here includes an adjusting element 102, which is configured, for example, as a screw nut and engages with the external thread on the steering tie rod using its internal thread. Furthermore, the adjusting element 102 can be driven by the motor 22 via a toothed belt, such that when the motor is running, the steering tie rod 27 is displaced to the right or left, thereby transmitting this movement to the wheels 5 and 6 via the tie rod 23. In this way, steering motion can be applied to the wheels 5 by the actuator 10. For a more detailed description or explanation of the function of the actuator 10, please refer to the following. Figure 5 and Figure 6 .

[0030] A device 105 is arranged on the motor 22, for example. The device 105 is configured to operate the motor 22 and, for example, to stop the motor in the event of a failure. Figure 2 The device 105 is described in more detail.

[0031] Figure 2 It shows the method for running according to Figure 1 A block diagram of an embodiment of the device 105 for the electric motor.

[0032] Device 105 is configured, for example, to disable the motor in the event of a malfunction. For this purpose, device 105 has a steering mechanism 200 and a control unit 205 located outside the steering mechanism 200. The steering mechanism 200 has a control device 210 and a sensor device 215, and is connected to the control unit 205, for example, in a manner capable of transmitting signals.

[0033] Sensor device 215 includes, for example, a rotor position sensor 220 and / or a linear displacement sensor 225. In the embodiment shown here, sensor device 215 includes a rotor position sensor 220 and a linear displacement sensor 225. The rotor position sensor 220 is configured, for example, to determine the position of a portion of the motor, particularly the angular position (rotor position) of the motor's rotor. The linear displacement sensor 225 is configured, for example, to determine the position of the adjusting element 102 in a linear drive element. For example, sensors 220 and 225 determine the position and / or length change of a portion of the motor or the position of the adjusting element of the actuator relative to a reference position. Therefore, sensor device 215 in which sensors 220 and 225 are arranged can also be referred to as a position sensor. Thus, sensors 220 and 225 are configured, for example, to measure position using an ASIL-D-based safety system.

[0034] ASIL stands for Safety Integrity Level and describes the level of safety requirements for safety-related systems in a motor vehicle. In the embodiments described herein, Safety Integrity Level D is discussed, where D represents the highest level of safety requirements.

[0035] In addition to ASIL, safety requirements QM are also defined, where QM stands for Quality Management Measures. Here, QM represents the lowest safety level, while ASIL-D, for example, represents the highest safety level. More precisely, the QM level represents simple and / or small quality management measures to ensure driving safety. Alternatively, if a QM level is not required, no safety-related measures are taken.

[0036] More precisely, functions need to meet certain safety specifications or standards to ensure safe operation, or in other words, to ensure operation that does not pose a danger to the body and life of vehicle occupants. In the automotive industry, requirements for this have been defined in different levels. For this purpose, the so-called Automotive Safety Integrity Levels (ASILs) have been defined, where these levels (also called grades) are guided by hazard analysis and risk estimation. This involves analyzing the potential hazards of the system and classifying possible functional failures in specific driving conditions into different safety requirement levels from A to D based on the estimated hazards or requirements. Here, level / grade A is considered the lowest level, and D is considered the highest level. When there is a risk to body and life, the ASIL safety level is used.

[0037] Therefore, the two sensors 220, 225 are configured, for example, to provide sensor signal 230 to control unit 205 using an ASIL-D-based safety system. Sensor signal 230 here represents the position of a portion of the motor and / or the position of an adjusting element, which is evaluated by control unit 205. In other words, sensor signal 230 represents, for example, the actual position of the actuator or the output of a rotor position sensor of the motor or a position sensor of a linear drive according to ASIL-D.

[0038] During the evaluation, control unit 205 is guided by the deactivation criteria. If sensor signal 230 meets the deactivation criteria, control unit 205 outputs a deactivation signal 235 to control device 210 to deactivate the motor. According to ASIL-D, deactivation signal 235 can also be referred to as an emergency shutdown signal.

[0039] If sensor signal 230 does not meet the deactivation criteria, then according to the embodiment, control unit 205 outputs preset signal 250 to control device 210. Here, preset signal 250 indicates a target value for the position of a portion of the motor or a target value for the position of the adjusting element, and that the motor is not deactivated. In other words, preset signal 250 may, for example, indicate a target value preset and non-safety-related diagnostic information.

[0040] According to an embodiment, in addition to evaluating the sensor signal 230, another signal, such as a vehicle signal 240, is provided to the control unit 205. The vehicle signal 240 is provided, for example, by a bus system 245 connected to the control unit 205 in a manner capable of transmitting signals. This bus system 245 may be referred to as a vehicle bus, and may be configured as a Flexray bus or a CAN bus. The vehicle signal 240 represents, for example, the vehicle's steering angle and / or speed or acceleration.

[0041] Vehicle signal 240 is also evaluated by control unit 205. If vehicle signal 240 meets the deactivation criteria, control unit 205 outputs deactivation signal 235 to control device 210.

[0042] Disabling criteria include, for example, excessive speed, steering angle and / or acceleration within an unacceptable range, and / or inconsistent positions of the two actuators (also known as dual controllers).

[0043] According to an embodiment, the bus system 245 is also connected to the control unit 210 in a signal-transmitting manner so as to directly transmit vehicle signals 240 to the control unit 210. This is typically accomplished by using an ASIL-based safety system.

[0044] According to an alternative embodiment, the bus system 245 is not connected to the control device 210 when a full evaluation is performed via the control unit 205.

[0045] In other words, a sensor device 215, also known as a position sensor, is arranged in the steering unit 200. This sensor device 215 typically includes a rotor position sensor 220 from the motor (also known as an electric motor) used to determine position. Alternatively or additionally, a linear displacement sensor 225 can be used to detect the position of the adjusting element in the linear drive unit. Both sensors 220 and 225 meet ASIL-D. The sensor device 215 measures the current position and transmits it as a sensor signal 230 directly to the control unit 205 (also known as the upper-level controller) via a bus (e.g., CAN bus or Flexray bus). If necessary, the sensor signal 230 is also received by the steering unit 200 via a bypass and used for motor commutation. Diagnostic and monitoring functions operate in the control unit 205 to ensure the safety objectives of the steering unit 200 are maintained.

[0046] If the control unit 205 detects a risk that the steering device 200 may violate safety objectives, such as a risk of misalignment between the positions of the two actuators, it disables the steering device 200 or the motor from the outside by emergency shutdown, thereby placing it in a safe state. For example, a circuit with an emergency braking function can be used to support this shutdown. As a result, the control device 210 in the steering device 200, which may consist of a µC (microcontroller) and a bridge, is completely bypassed, and therefore no safety function is implemented therein.

[0047] According to an alternative embodiment, the control unit 205 may also operate two actuators if necessary. When two actuators are used, for example, one actuator represents part of the control unit 205, while the other actuator does not have complete ASIL electronics.

[0048] Figure 3 A flowchart illustrating an embodiment of a method 300 for operating a device is shown. Here, the device is similar to or corresponds to the device in one of the above figures.

[0049] Method 300 includes step 305 of providing at least one sensor signal. Here, the sensor signal indicates the position of the motor and / or the position of the adjusting element of the steering device. Furthermore, method 300 includes step 310 of providing a deactivation signal to deactivate the motor in response to at least one sensor signal.

[0050] Figure 4 A schematic diagram of an embodiment of a motor vehicle 100 is shown.

[0051] For the motor vehicle 100, wheels 405 (e.g., only two driven wheels or steering wheels 405 are shown), an energy storage device 410 (e.g., a battery), and an electric actuator 415 for a steer-by-wire system are shown. The electric actuator 415 for the steer-by-wire system includes a device 105, a motor 22, and a transmission 430, which is configured, for example, as a linear actuator for steering the wheels.

[0052] Electrical energy for operating motor 22 is provided by an energy supply device (here, an energy storage device 410). The energy storage device 410 is configured to provide direct current (DC) power, which is supplied to operate motor 22 in the case of a device 105 for an electric actuator 415 for a steer-by-wire system. The shaft driven by motor 22 is coupled directly or via a transmission 430 to at least one wheel 405 of vehicle 100. Therefore, vehicle 100 can be steered using motor 22. According to an embodiment, the electric actuator 415 for a steer-by-wire system includes a housing in which the device 105, motor 22, and transmission 430 are arranged.

[0053] According to an embodiment, the drive 415 for the steer-by-wire system includes at least one device 105 as described in the foregoing figures.

[0054] Figure 5 It shows Figure 1 A schematic diagram of the actuator 10 is shown. The actuator 10 has a housing 21 on which the motor 22 is arranged parallel to its axis. A screw drive 20, consisting of a screw nut 25 and a steering tie rod designed as a threaded screw 27g, is arranged within the housing 21. In this embodiment, the screw nut 25 can be understood as... Figure 1 The adjusting element 102 is located in the housing 21. The lead screw nut 25 is fixed in position and rotatable relative to the housing 21 via a rolling bearing 29. A threaded lead screw 27g passes through and is coaxially arranged with the lead screw nut 25. On the side of the lead screw nut 25 opposite to the rolling bearing 29, a pulley 30 is arranged on the lead screw nut 25 in a non-rotatable manner. The motor 22, also referred to as an electric motor, has a drive pinion 32. A drive belt 34, in the form of a toothed belt, surrounds both the drive pinion 32 and the pulley 30, such that when the electric motor 22 rotates, the lead screw nut 25 rotates about the longitudinal axis a without slipping. The drive pinion 32, pulley 30, and drive belt 34 form an intermediate transmission device. Depending on the rotation direction of the lead screw nut 25, the steering rod 27 or the threaded lead screw 27g is linearly displaced along the longitudinal axis a in one direction or the other, depending on the rotation direction of the electric motor 22. When force F... ext Basically, when axial force is applied to the steering tie rod 27, the lead screw nut 25 tends to rotate, thus due to the force F extThis generates torque. Therefore, if no measures are taken to counteract this effect, motor 22 will also rotate, potentially causing the steering tie rod 27 to shift axially in the reverse drive direction. This is particularly undesirable in the event of a malfunction, such as when the actuator is de-energized, and could lead to uncontrolled changes in the wheel steering angle.

[0055] A device 105, similar to or corresponding to the device in one of the above figures, is arranged next to the electric motor 22. The device 105 is configured to deactivate the electric motor 22 in the event of a malfunction.

[0056] Figure 6 An actuator 601 for a rear axle steering system with steer-by-wire is shown, the actuator having a housing 620 fixed to one side of the vehicle. Within the housing 620 is a screw driver 630 having an externally threaded screw 640 that is axially movable but not rotatable, and a screw nut 650 with a common internal thread that is rotatable in the direction of rotation. The engaged threads form a moving thread for axial displacement of the screw 640 relative to the housing 620 or the screw nut 650. The screw nut 650 can be driven in the direction of rotation by an electric motor 22 via a traction drive or belt 660, and is rotatably supported in the housing 620 and fixed in the axial direction by rolling bearings 680. The screw 640 is connected at both ends to bearing sleeves 690, 610 (also referred to as screw-on plugs) guided on the housing side, these bearing sleeves themselves being connected to pivot pins 611, 612 arranged on the outside of the housing 620. Pivot pins 611 and 612 are directly connected to the wheel brackets, or indirectly connected to the wheel brackets via guide rods or tie rods. Therefore, actuator 601 is configured as a so-called central adjuster, that is, it is centrally located in the vehicle and simultaneously acts on the steering of both rear wheels.

[0057] A device 105, similar to or corresponding to the device in one of the above figures, is arranged next to the electric motor 22. The device 105 is configured to deactivate the electric motor 22 in the event of a malfunction.

[0058] Figure 7 A vehicle 800 with a steerable front axle 821 and a steerable rear axle 831 is schematically shown. To steer the wheels 802 at the front axle 821, a steering system 804 is provided, which allows the wheels 802 to adjust or change the front wheel steering angle δ via a steering guide rod 841. v The angle δ is illustrated exemplarily at point 802 on the right wheel. v At the rear axle 831, the steer-by-wire system 805 is responsible for adjusting or changing the wheel steering angle δ at the rear wheel 803 via another steering guide rod 851. hIn the illustrated embodiment, the wheels at the front axle steering system 804 and the rear axle steering system 805 steer in opposite directions, resulting in a smaller turning radius and better parking capabilities at low speeds, such as below 50 km / h, compared to a vehicle with only one axle steering. Two-axle steering also advantageously improves autonomous driving. Here, the driver typically sets the steering angle at the front axle 821 via the steering wheel 814, where the steering angle Lw is detected by a sensor unit and transmitted via signal lines to the front axle steering system 804, which is configured as a steer-by-wire system, to set the steering angle. The sensor unit for transmitting the steering angle Lw is electrically connected via a CAN bus system to the controller of the steer-by-wire system 805, configured as the rear axle steering system. The CAN bus system is, for example, a CAN bus. Through the bus system, the steering function for driver assistance systems (ADAS), the correction function Korr for limiting the maximum steering angle, the parking assist system (PAS) for automatic parking, and the electronic stability controller (ESC) are electrically connected to the controller (SG) of the rear axle steering system 805. At the center of gravity S... G Yaw rate R measured at the location G The speed of rotation is determined by appropriate sensors (rotational speed sensors) at the center of gravity of vehicle 800 and detected or evaluated by the Electronic Stability Control (ESC). Sensors S, belonging to the sensing mechanism, are arranged at the outer ends of vehicle 800 and are used to identify the vehicle's surrounding environment. These sensors can be temperature sensors, optical sensors such as cameras, or lidar or radar suitable for temperature, distance, or optical detection of the lane. Weather conditions (e.g., humidity) or the temperature on the lane can be detected and provided to the controller SG. Vehicle 800 travels along trajectory T, which is schematically shown in the figure at the front of vehicle 800 along its direction of travel.

[0059] The controller SG may have, for example, a device 105 that is similar to or corresponds to the device in one of the above figures.

[0060] List of reference numerals in the attached diagram:

[0061] 1. Vehicle axle

[0062] 2 Subframe

[0063] 3-link

[0064] 5. First wheel

[0065] 6. Second wheel

[0066] 8 First wheel steering angle

[0067] 9. Steering angle of the second wheel

[0068] 10 Actuators

[0069] 12 Steering System

[0070] 20 Lead Screw Driver

[0071] 21. Shell

[0072] 22. Electric motors

[0073] 23. Tie rod

[0074] 25 Lead screw nut

[0075] 27. Steering tie rod

[0076] 27g threaded screw

[0077] 29 Rolling bearings

[0078] 30 pulley

[0079] 32 Drive pinion

[0080] 34 drive belt

[0081] 100 motor vehicles

[0082] 102 Adjustment element

[0083] 105 Equipment

[0084] 200 Steering System

[0085] 205 Control Unit

[0086] 210 Control device

[0087] 215 Sensor Device

[0088] 220 Rotor Position Sensor

[0089] 225 Linear Displacement Sensor

[0090] 230 Sensor Signal

[0091] 235 Disconnect signal

[0092] 240 vehicle signal

[0093] 245 bus system

[0094] 250 Preset Signal

[0095] 300 methods

[0096] 305 Steps for providing sensor signals

[0097] 310 Steps for providing a deactivation signal

[0098] 405 wheels

[0099] 410 Energy Storage

[0100] 415 Electric actuator for steer-by-wire systems

[0101] 430 Transmission device

[0102] 601 Actuator

[0103] 610 bearing sleeve

[0104] 611 Pivot Pin

[0105] 612 Pivot Pin

[0106] 620 housing

[0107] 630 Screw Driver

[0108] 640 lead screw

[0109] 650 lead screw nut

[0110] 660 tape

[0111] 680 rolling bearing

[0112] 690 bearing sleeve

[0113] 701 Actuator

[0114] 702 Housing

[0115] 703 Universal Joint Fork

[0116] 704 universal joint fork

[0117] 705 lead screw

[0118] 705a Kinematic Thread

[0119] 706 Screw Nut

[0120] 706a internal thread

[0121] 708 Fixed End

[0122] 709 Another fixed end

[0123] 710 bearing journal

[0124] 711 Another bearing journal

[0125] 712 sliding bearing

[0126] 713 Another sliding bearing

[0127] 714 bolts

[0128] 715 bolts

[0129] 800 vehicles

[0130] 802 front wheel

[0131] 803 rear wheel

[0132] 804 Front Axle Steering System

[0133] 805 Rear Axle Steering System

[0134] 814 Steering Wheel

[0135] 821 Front Axle

[0136] 831 Rear Axle

[0137] 841 Steering Guide Rod

[0138] 851 Another steering guide rod

[0139] CAN bus system

[0140] ESC Electronic Stability Controller

[0141] Korr Correction Function

[0142] PAS (Parking Assist System)

[0143] R G Yaw rate

[0144] SG controller

[0145] S G Center of gravity

[0146] S-sensor mechanism

[0147] T-trajectory

[0148] δ v Front wheel steering angle

[0149] δ h Rear wheel steering angle

[0150] Lw Driver's steering angle

[0151] F ext force

[0152] a longitudinal axis

[0153] T-trajectory.

Claims

1. A device (105) for operating a motor (22) for a steer-by-wire system, characterized in that, The device (105) has the following characteristics: Steering device (200), the steering device including control device (210) and sensor device (215), wherein the sensor device (215) is configured to provide at least one sensor signal (230) indicating the position of a portion of the motor (22) and / or the position of the adjustment elements (102, 650, 706) of the steering device (200); and A control unit (205) external to the steering device (200) is configured to evaluate the position of a portion of the motor (22) and / or the position of the adjustment elements (102, 650, 706) of the steering device (200) in response to at least one of the sensor signals (230), and to provide a deactivation signal (235) to the control device (210) to deactivate the motor (22) when the sensor signal (230) meets the deactivation criteria.

2. The device (105) according to claim 1, characterized in that, The sensor device (215) has at least one rotor position sensor (220) and / or linear displacement sensor (225) to provide the sensor signal (230).

3. The device (105) according to claim 1 or 2, characterized in that, The sensor device (215) is configured to provide the sensor signal (230) when a portion of the motor (22) and / or the adjustment elements (102, 650, 706) of the steering device (200) are in a deactivated range.

4. The device (105) according to claim 1 or 2, characterized in that, The control unit (205) is configured to provide the control device (210) with a preset signal (250) different from the deactivation signal (235) in response to at least one of the sensor signals (230), wherein the preset signal (250) represents a target value of the position of a portion of the motor (22) and / or the position of the adjustment elements (102, 650, 706) of the steering device (200).

5. The device (105) according to claim 4, characterized in that, When the position of a part of the motor (22) deviates from the position of the part of the motor (22) indicated by the preset signal (250) and / or the position of the adjusting element (102, 650, 706) of the steering device (200) by more than the tolerance range, the control unit (205) outputs the deactivation signal (235).

6. The device (105) according to claim 5, characterized in that, The device is installed on a motor vehicle (100), wherein the control unit (205) outputs the deactivation signal (235) when the motor vehicle (100) has a speed higher than the target value, a steering angle within an unacceptable range, and / or the positions of the two actuators are inconsistent.

7. The device (105) according to claim 5 or 6, characterized in that, The sensor device (215) is configured to provide at least one of the sensor signals (230) by using an ASIL-based security system.

8. The device (105) according to claim 5 or 6, characterized in that, The steer-by-wire system is the rear axle steering system (805) of the motor vehicle (100).

9. An electric actuator for a steer-by-wire system (415) of a motor vehicle, the electric actuator having at least one motor (22) and a transmission (430), characterized in that, The device (105) is provided according to any one of claims 1 to 8.

10. A control device, characterized in that, The control device is used to operate the equipment according to any one of claims 1 to 8.

11. A steer-by-wire system (415), characterized in that, The steer-by-wire system has an electric actuator as described in claim 9 and uses a control device as described in claim 10.

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