JP6488585B2 - Vehicle control device - Google Patents

Description

  The present invention relates to a vehicle control device that controls an in-vehicle motor.

  A motor is mainly used as a power source such as an actuator for adjusting the optical axis of the headlamp or a shutter. When a driven member such as a headlamp or a shutter comes into contact with a foreign object while these motors are in operation, the operation of the motor that is a power source is hindered, and control as intended is difficult. Even if the motor is not operating, the actual position of the output shaft of the motor will be reduced if the shutter, which is a driven member, is pry open or the optical axis of the headlamp is bent by an external force. And the position of the output shaft indicated by the command signal for controlling the motor, and the control as intended is difficult.

  In Patent Document 1, a torque sensor is provided on a winding shaft that rotates in synchronization with an output shaft of a motor, and an external force acts on a driven member such as a shutter from a change in torque of the winding shaft detected by the torque sensor. An invention of an opening / closing device for detecting this is disclosed.

JP 2004-232385 A

  However, although the opening / closing device described in Patent Document 1 can detect that an external force has acted on the shutter due to a change in the torque of the winding shaft, the actual position of the winding shaft by the action of the external force is the position of the command signal. There was a problem that it was not possible to clarify how much the deviation occurred. In the determination based on the change in the torque of the reel, the change in the torque of the reel when an external force is applied to a driven member such as a shutter, and the change in the torque of the reel when an abnormality occurs in the motor There was also a problem that could not be clearly distinguished.

  In general, a sensor that detects the rotation of a Hall IC or the like is used to detect the transition of the position of the output shaft. For example, the actual position of the output shaft of the motor detected by the Hall IC is compared with the position of the output shaft indicated by the command signal, and if there is a difference between the two, it can be determined that some abnormality has occurred. . Further, by calculating the difference between the actual position of the output shaft detected by the Hall IC and the position of the output shaft indicated by the command signal, the actual position of the output shaft of the motor becomes the position of the output shaft indicated by the command signal. It is possible to clarify how much it deviates from

  However, whether the difference between the actual position of the output shaft detected by the Hall IC and the position of the output shaft indicated by the command signal is caused by abnormal operation of the motor itself, or the result of external force acting on the motor output shaft. There was a problem that it was not possible to distinguish whether it occurred.

  The present invention has been made in view of the above, and an object of the present invention is to provide a vehicle control device that can discriminate and detect abnormalities in motor operation or abnormalities when an external force is applied to the output shaft of the motor.

In order to solve the above-mentioned problem, the vehicle control device according to claim 1 includes a motor that drives a driven member by rotation of an output shaft via a speed reduction portion, and a sensor provided at an end of the output shaft. A rotation angle detector for detecting a rotation angle of the output shaft from a change in magnetic field according to rotation of the output shaft of the magnet, and when the motor stops rotating by control based on a command signal from a host controller . wherein a storage unit rotation angle detecting unit stores the rotation angle of the output shaft detected, it controls the rotation angle of the motor based on the command signal of the rotation angle from the upper control device, during rotation of the motor to the difference of the rotational angle detecting unit and the command signal indicates the position of the rotation angle and the rotation angle detected is determined to be abnormal in the motor when exceeding the predetermined range, the rotational angle the motor during the stop The difference between the stored rotation angle current rotation angle of the detection unit detects the said storage unit comprises a abnormality determining control unit of the output shaft by the action of an external force when exceeding a predetermined range.

According to this vehicle control device, when the motor is operating, the control unit has a predetermined range in which the difference between the rotation angle of the output shaft indicated by the command signal and the rotation angle of the output shaft detected by the rotation angle detection unit is within a predetermined range. If exceeded, the motor is determined to be abnormal. In addition, when the motor is stopped, the control unit detects the external force when the difference between the rotation angle stored in the storage unit and the rotation angle of the output shaft detected by the rotation angle detection unit exceeds a predetermined range. It is determined that the output shaft is abnormal due to action. As a result, abnormalities in motor operation or abnormalities when an external force acts on the output shaft of the motor can be discriminated and detected.

  The vehicle control device according to claim 2 is the vehicle control device according to claim 1, wherein the control unit outputs the determined result to the host control device.

  According to this vehicle control device, abnormalities in the operation of the motor or abnormalities when an external force is applied to the output shaft of the motor are discriminated and output to the host control device, whereby abnormalities in the product using the motor are detected. It can contribute to investigation of the cause of operation.

  The vehicle control device according to claim 3 is the vehicle control device according to claim 1 or 2, wherein the rotation angle detector is a Hall IC having a Hall element and a Schmitt trigger, and the Hall element is connected to the output shaft. A magnetic field that changes in accordance with the rotation angle of the output shaft of the provided permanent magnet is detected and a signal in accordance with the change in the magnetic field is output. The circuit including the Schmitt trigger digitally outputs an analog signal output from the Hall element. Convert to signal.

  According to this vehicle control device, the rotation angle of the output shaft that is detected to discriminate abnormalities in the operation of the motor or in the case where an external force is applied to the output shaft of the motor is determined using the Hall IC that is a general-purpose component. Can be detected.

It is the schematic which shows an example of a structure of the control apparatus for vehicles which concerns on embodiment of this invention. It is the schematic which shows the position of Hall IC of the motor which concerns on embodiment of this invention. It is sectional drawing which shows the cross section which cut | disconnected the motor along the AA line shown by FIG. It is the schematic which showed an example of the circuit structure of the rotation angle detection part of the control apparatus for vehicles which concerns on embodiment of this invention. It is the graph which showed an example of the Hall IC signal which the rotation angle detection part of the control device for vehicles concerning an embodiment of the invention outputted. It is the flowchart which showed an example of control of the control apparatus for vehicles which concerns on embodiment of this invention.

  FIG. 1 is a schematic diagram illustrating an example of a configuration of a vehicle control device 10 according to the present embodiment. The vehicle control device 10 is a device that controls the motor 18 that drives the driven member 50 with the rotational force of the output shaft 36. The driven member 50 shown in FIG. 1 is a vehicle headlamp as an example, and the motor 18 rotates based on the control of the motor control circuit 20 to adjust the optical axis of the headlamp.

  The vehicle control apparatus 10 according to the present embodiment includes a motor control circuit 20 that controls the motor 18 and a rotation angle detector 40 that detects the rotation angle of the output shaft 36 of the motor 18. The motor control circuit 20 includes a microcomputer 26 that controls the driver circuit 28 so that the motor 18 rotates based on a command signal received from a host ECU such as a main ECU (Electronic Control Unit) of the vehicle. The microcomputer 26 is connected to a 5V regulator 24 that adjusts the power of approximately 12V of an on-vehicle battery as a power source to 5V, and the microcomputer 26 operates by the power supplied via the 5V regulator 24.

  The driver circuit 28 generates a voltage (current) for operating the motor 18 by PWM (Pulse Width Modulation) control and supplies it to the motor 18. If the motor 18 is a brushless DC motor, the driver circuit 28 includes a three-phase inverter circuit using a field effect transistor (MOSFET) as a switching element, and outputs a voltage with a predetermined duty ratio under the control of the microcomputer 26. .

  The Hall IC 42 of the rotation angle detection unit 40 operates with the power supplied via the 5V regulator 24 to detect the magnetic field of the sensor magnet 68 provided coaxially with the output shaft 36, and responds to the detected change in the magnetic field. The signal is output to the microcomputer 26. The microcomputer 26 calculates the rotation angle of the output shaft 36 based on the detected magnetic field, and compares the calculated rotation angle with the command value of the rotation angle of the command signal received from the host ECU, and the comparison result Is sent to the host ECU as a status reply.

  In the present embodiment, the microcomputer 26 includes a previous value storage RAM (Random Access Memory) 26A that stores the value of the rotation angle calculated based on the signal output from the Hall IC 42 when the motor 18 was previously operated. The value of the rotation angle stored in the previous value storage RAM 26A is, for example, determined by the Hall IC 42 when the motor 18 is stopped during the previous operation of the motor 18 by the control of the microcomputer 26 based on the command signal from the host ECU. This is the detected rotation angle. In the present embodiment, the microcomputer 26 compares the rotation angle detected by the Hall IC 42 with the rotation angle stored in the previous value storage RAM 26A when the motor 18 is not operating, and there is a difference between the two. If there is, it is determined that some external force has acted on the headlamp which is the driven member 50 and the optical axis of the headlamp has changed. The case where there is a difference between the rotation angle detected by the Hall IC 42 and the rotation angle stored in the previous value storage RAM 26A is a case where the difference between the two exceeds a predetermined range. Further, the difference between the rotation angle detected by the Hall IC 42 and the rotation angle stored in the previous value storage RAM 26A is the difference between the rotation angle stored in the previous value storage RAM 26A and the rotation angle detected by the Hall IC 42, or Is the ratio.

  The previous value storage RAM 26A stores the previously stored rotation angle information as new rotation angle information when storing the rotation angle of the output shaft 36 detected by the Hall IC 42 when the motor 18 stops operating. It may be overwritten and saved.

  FIG. 2 is a schematic diagram showing the position of the Hall IC 42 of the motor 18 according to the present embodiment. As shown in FIG. 2, the motor 18 is adjacent to a coil 86 that generates a rotating magnetic field in the circumferential direction of a rotor 88 formed of a permanent magnet. A worm 22A is formed at the end of a rotor shaft 88A extending from the rotor 88, and the worm 22A meshes with a worm wheel 22B formed integrally with the output shaft 36. In the present embodiment, the worm 22A and the worm wheel 22B constitute the speed reduction mechanism 22. A sensor magnet 68 is attached to one end of the output shaft 36, and a Hall IC 42 is provided facing the sensor magnet 68.

  FIG. 3 is a cross-sectional view showing a cross section of the motor 18 taken along line AA shown in FIG. The worm 22A is formed in a spiral shape along the axial direction of the rotor shaft 88A. Further, the worm wheel 22B is formed in a disc shape, and a spur tooth groove is formed along the circumferential direction thereof. By meshing the helical tooth groove of the worm 22A and the tooth groove of the worm wheel 22B, the rotation of the rotor 88 can be decelerated at a predetermined reduction ratio and transmitted to the output shaft 36. A sensor magnet 68 is attached to the center of the bottom surface of the worm wheel 22B corresponding to the end of the output shaft 36.

  A substrate 76 of the vehicle control device 10 according to the present embodiment is provided immediately below the speed reduction mechanism 22 in the upper housing 78A. The substrate 76 is protected by being covered by the lower housing 78B, and elements and the like constituting the motor control circuit 20 are mounted on the substrate 76. Further, in the portion of the substrate 76 facing the sensor magnet 68 provided at the end of the output shaft 36, a signal indicating the change in the magnetic field is detected by detecting the magnetic field of the sensor magnet 68 that changes as the output shaft 36 rotates. Is mounted.

  FIG. 4 is a schematic diagram illustrating an example of a circuit configuration of the rotation angle detection unit 40 of the vehicle control device 10 according to the present embodiment. The rotation angle detection unit 40 according to the present embodiment uses, as a magnetic detection signal, a change in the current I of the circuit of the rotation angle detection unit 40 due to the Hall IC 42 detecting a change in the magnetic field. The current I of the entire circuit is detected by the shunt resistor R1 and the amplifier 60.

  In the Hall IC 42, the power supply voltage (Vcc) from the 5V regulator 24 shown in FIG. 1 is applied to the power supply terminal 42A via the shunt resistor R1, and the ground terminal 42D is grounded. The Hall IC 42 includes a Hall element that generates an electromotive force in a direction orthogonal to the applied voltage Vcc and the magnetic field due to a so-called Hall effect when a magnetic field is detected when the voltage Vcc is applied to the power supply terminal 42A. It is out. Further, the Hall IC 42 converts a change in electromotive force generated in the Hall element due to the detection of the magnetic field into a digital signal by a circuit such as a Schmitt trigger (not shown), and outputs a high level between the output terminal 42B and the output terminal 42C. Output as potential difference shown as low level. The output stage of the Hall IC 42 is an NPN-type bipolar transistor, the collector of the bipolar transistor is the output terminal 42C described above, a circuit including a Hall element and a Schmitt trigger is connected to the base, and the emitter is Grounded.

  One end of a resistor R2 is connected to the output terminal 42B of the Hall IC 42. The other end of the resistor R2 is connected to the power supply terminal 42A. One end of the capacitor C1 is connected to the power supply terminal 42A, and the other end is grounded. Capacitor C1 is an element for accumulating an overvoltage and releasing it to the ground region when there is a possibility that an overvoltage from Vcc is applied to output terminal 42B. If the overvoltage of the circuit does not matter, the capacitor C1 may be omitted.

  In the present embodiment, when the potential of the output terminals 42B and 42C changes due to the Hall element detecting a magnetic field, the current I of the entire circuit of the rotation angle detector 40 changes. For example, when the potentials of the output terminals 42B and 42C are at a low level, current easily flows from Vcc to the output terminal 42B of the Hall IC 42, and the current I increases. Further, when the potentials of the output terminals 42B and 42C are at a high level, it becomes difficult for current to flow from Vcc to the output terminal 42B of the Hall IC 42, and the current I becomes small. In the present embodiment, the change in the current I is detected by the shunt resistor R1 and the amplifier 60.

  FIG. 5 is a graph showing an example of the Hall IC signal output by the rotation angle detector 40 of the vehicle control apparatus 10 according to the present embodiment. As described above, the Hall IC used in this embodiment includes a circuit such as a Schmitt trigger that converts an analog signal into a digital signal. Therefore, the signal output by the rotation angle detection unit 40 is indicated on the horizontal axis. It becomes a rectangular wave that changes between a high level and a low level according to the position (rotation angle) of the output shaft.

  If the rotation angle detection unit 40 is a type that outputs a change in the current value of the circuit as shown in FIG. 4, the Hall IC signal shown in FIG. 5 represents the current of the circuit of the rotation angle detection unit 40. It is a rectangular wave indicating a change in value. In the present embodiment, the rotation angle detector 40 may not be configured as shown in FIG. 4, and the signals output from the output terminals 42B and 42C of the Hall IC 42 may be output to the microcomputer 26 as Hall IC signals. In such a case, the Hall IC signal shown in FIG. 5 is a rectangular wave indicating the potential difference between the output terminals 42B and 42C of the Hall IC 42.

  FIG. 6 is a flowchart showing an example of the control of the vehicle control apparatus 10 according to the present embodiment. In step 600, the microcomputer 26 resets all abnormalities in the vehicle control device 10.

  In step 602, it is determined whether or not a command signal for operating the motor 18 is input from the host ECU. If the determination in step 602 is affirmative, it is determined whether or not the position of the output shaft (rotation angle) indicated by the Hall IC signal output from the rotation angle detection unit 40 in step 604 matches the position indicated by the command signal. To do. In step 604, when the difference between the position of the output shaft indicated by the Hall IC signal and the position indicated by the command signal is within a predetermined range, it is determined that the two match. The difference between the position of the output shaft indicated by the Hall IC signal and the position indicated by the command signal is the difference or ratio between the position of the output shaft indicated by the Hall IC signal and the position indicated by the command signal. For example, if the determination is based on the difference between the two, if the position of the output shaft indicated by the Hall IC signal is within a predetermined range centered on the position indicated by the command signal, it is determined that the two match. As an example, the predetermined range is ± 10 degrees with respect to the center value. Further, if the determination is made based on the ratio between the two, it is determined that they match when the ratio (%) of the position of the output shaft indicated by the Hall IC signal to the position indicated by the command signal is within a predetermined range. For example, the predetermined range is ± 1 to 2% with respect to the position indicated by the command signal.

  If the determination in step 604 is affirmative, the procedure returns to step 602. If a negative determination is made in step 604, some abnormality has occurred in the motor 18, and the position of the output shaft 36 is different from the position indicated by the command signal. Therefore, in step 606, the determination result of "motor abnormality" is sent to the host ECU. Output and finish the process.

Negative determination in step 602, i.e., when a command signal for operating the motor 18 is not input in step 60 8, the position of the output shaft indicated by the Hall IC signal is stored in the previous value storage RAM26A It is determined whether or not it matches the position of the output shaft. In step 608, when the difference between the position of the output shaft indicated by the Hall IC signal and the position of the output shaft stored in the previous value storage RAM 26A is within a predetermined range, it is determined that the two match. The difference between the position of the output shaft indicated by the Hall IC signal and the position of the output shaft stored in the previous value storage RAM 26A is the difference between the position of the output shaft indicated by the Hall IC signal and the output shaft stored in the previous value storage RAM 26A. The difference or ratio from the position. For example, if the determination is based on the difference between the two, if the position of the output shaft indicated by the Hall IC signal is within a predetermined range centered on the position of the output shaft stored in the previous value storage RAM 26A, It is determined that they match. As an example, the predetermined range is ± 10 degrees with respect to the center value. If the determination is based on the ratio between the two, if the ratio (%) of the position of the output shaft indicated by the Hall IC signal to the position of the output shaft stored in the previous value storage RAM 26A is within a predetermined range, both Are determined to match. As an example, the predetermined range is ± 1 to 2% with respect to the position of the output shaft stored in the previous value storage RAM 26A.

  If the determination in step 608 is affirmative, the procedure returns to step 602. In the case of negative determination in step 608, since some external force is applied to the driven member 50, the determination result of “abnormal external force” is output to the host ECU in step 610, and the process is terminated.

  As described above, in the present embodiment, when the position of the output shaft indicated by the Hall IC signal matches the position of the output shaft indicated by the command signal when the motor 18 is operated, the motor does not operate. In this case, it is determined whether or not it matches the position of the output shaft at the previous operation. With this determination, it is possible to determine and detect an abnormality in the operation of the motor or an abnormality when an external force is applied to the output shaft of the motor.

  Further, the abnormality of the operation of the motor 18 or the abnormality when the external force is applied to the output shaft 36 of the motor 18 is discriminated and output to the host ECU to investigate the cause of the abnormal operation of the product using the motor 18. Can contribute.

DESCRIPTION OF SYMBOLS 10 ... Vehicle control apparatus, 18 ... Motor, 20 ... Motor control circuit, 22 ... Deceleration mechanism, 22A ... Worm, 22B ... Worm wheel, 24 ... 5V regulator, 26 ... Microcomputer, 26A ... Previous value storage RAM, 28 ... Driver circuit 36 ... Output shaft 40 ... Rotation angle detector 42 ... Hall IC 42A ... Power supply terminal 42B, 42C ... Output terminal 42D ... Ground terminal 50 ... Driven member 60 ... Amplifier 68 ... Sensor Magnet, 76 ... substrate, 78A ... upper housing, 78B ... lower housing, 86 ... coil, 88 ... rotor, 88A ... rotor shaft

Claims (3)

A motor that drives the driven member by rotation of the output shaft via the speed reducer;
A rotation angle detector that detects a rotation angle of the output shaft from a change in magnetic field according to rotation of the output shaft of a sensor magnet provided at an end of the output shaft;
A storage unit for storing a rotation angle of the output shaft detected by the rotation angle detection unit when the motor stops rotating by a control based on a command signal from a host controller ;
Rotation controls the rotation angle of the motor based on the command signal of the rotation angle from the upper control apparatus, during rotation of the motor, which the rotation angle detecting unit and the position indicated by the command signal of the rotation angle is detected When the difference from the angle exceeds a predetermined range, it is determined that the motor is abnormal, and the current rotation angle detected by the rotation angle detection unit while the motor is stopped and the rotation angle stored in the storage unit A controller that determines that the output shaft is abnormal due to the action of an external force when the difference exceeds a predetermined range;
A vehicle control apparatus including:   The vehicle control device according to claim 1, wherein the control unit outputs a determined result to the host control device. The rotation angle detection unit is a Hall IC having a Hall element and a Schmitt trigger, and the Hall element detects a magnetic field that changes according to the rotation angle of the output shaft of a permanent magnet provided on the output shaft, and detects the magnetic field. The vehicle control device according to claim 1, wherein a signal corresponding to a change is output, and a circuit including the Schmitt trigger converts an analog signal output from the Hall element into a digital signal.

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