JP4255408B2 - Vehicle lighting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To precisely detect a rotating direction and a rotating position of a motor by eliminating noise effect superimposed on a signal from a detecting element detecting the rotating position of the motor. <P>SOLUTION: The lighting device for the vehicle is equipped with a driving motor 42 for a light axis deflecting means for deflecting the lighting device provided on the vehicle, detecting elements H1 to H3 outputting the signal for detecting the rotating position of the driving motor, and a motor control means 433 for controlling a rotating operation of the driving motor based on the detected rotating position. The lighting device is equipped with a means 434 which detects abnormality of the signals P1 to P3 from the detecting elements and detects the rotating position of the driving motor by correcting the abnormal signal based on the normal signal when detecting the abnormality. When the rotating position and/or rotating direction of the motor cannot be normally detected because the noise is superimposed on the signal outputted from the detecting element, the correction is performed based on the normal signal obtained around the time, and the rotating direction and the rotating position of the motor can be precisely detected. <P>COPYRIGHT: (C)2006,JPO&amp;NCIPI

Description

  The present invention relates to a light distribution control means for deflecting an irradiation direction and an irradiation range of a lamp such as a headlamp in accordance with a traveling state of a vehicle such as an automobile, for example, an adaptive lighting system (hereinafter referred to as an AFS (Adaptive Front-lighting System)). In particular, the present invention relates to a motor drive device as a drive source for performing a deflection operation.

As an AFS proposed for improving the driving safety of an automobile, there is a technique described in Patent Document 1 proposed by the present applicant. As shown in the conceptual diagram of FIG. 1, the AFS is provided with a steering sensor 1A for detecting a steering angle in a steering device and a vehicle speed sensor 1B for detecting a vehicle speed in an automobile CAR, and detection outputs of these sensors 1A and 1B. Is input to an electronic control unit (hereinafter referred to as an ECU (Electronic Control Unit)) 2, and the ECU 2 is connected to headlights 3 (swive lamps 3R, 3L) mounted on the left and right of the front of the vehicle based on the input detection output. ), For example, the irradiation direction is deflected to the left and right to change its light distribution characteristics. According to this AFS, when the vehicle travels on a curved road, it becomes possible to illuminate the road ahead of the curve by controlling the deflection direction of the swivel lamp according to the steering angle of the vehicle, This is effective for improving driving safety.
JP 2002-160581 A

  In such an AFS, a motor is provided as a drive source for the left and right swivel lamps, the rotation output of the motor is decelerated by a reduction gear train, and the rotation shaft that becomes the deflection center of the swivel lamp is rotated to deflect each swivel lamp. The deflection control is configured to set the irradiation direction of each swivel lamp to a predetermined direction by controlling the rotational position of the motor. In order to control the rotational position of the motor, the rotational position of the motor is detected by a motor rotational position sensor, the detected rotational position is compared with the target rotational position to be set, and the difference between the two is obtained. A configuration is adopted in which feedback control is performed in the motor drive circuit so as to be zero. Normally, when a brushless motor is used as a motor, detection signals of a plurality of Hall elements attached to the brushless motor are used to detect the rotational position of the brushless motor. A plurality of these Hall elements are originally arranged along the rotation direction of the brushless motor. When the rotor of the motor is rotated, the magnetic field in each Hall element is changed, and the ON / OFF state of each Hall element is changed. This is provided to output a rectangular wave pulse signal corresponding to the rotation cycle of the rotor and to control the rotation operation of the brushless motor based on this output.

  FIG. 9 is a diagram for explaining a technique for controlling the rotational position using a Hall element. Here, as schematically shown in FIG. 9A, the rotor R has S and N poles arranged at a circumferential angle of 180 degrees, and three Hall elements H1, H2, H2 are arranged around the rotor R. H3 is arranged at a circumferential angle of 120 degrees. Therefore, when the rotor R rotates and the magnetic field applied to each of the Hall elements H1, H2, and H3 changes, as shown in FIG. 9B, the rectangular wave pulse signal P1 having a phase different from each other by 1/3 period from each Hall element. , P2, P3 are output. Therefore, by encoding each pulse signal P1, P2, P3 as a 3-bit digital value with “1” and “0”, 16 of “1H” to “6H” as shown in FIG. 9C. Convert to hexadecimal digital value. When these digital values are arranged along the CCW direction, the order is “5H”, “1H”, “3H”, “2H”, “6H”, “4H”. Therefore, as shown in FIG. 9D, in the motor drive circuit that controls the drive of the motor, the states corresponding to these values are the states “J1”, “J2”, “J3”, “J4”, “J5”, respectively. ”And“ J6 ”, and this state is detected to detect the rotational direction and rotational position of the motor. That is, the rotational position of the motor is determined by the values of the states “J1” to “J6”, and whether or not the motor is correctly rotated in the CW direction or the opposite CCW direction is determined in the states “J1” to “J6”. Can be easily determined by detecting whether or not "" is detected in this order or the reverse order.

  In such a rotation direction detection technique, when noise is superimposed on the Hall element signal, an error occurs in the obtained hexadecimal digital value, and as a result, errors also occur in the states “J1” to “J6”. For example, as shown by a chain line in FIG. 9B, when noise is superimposed on a part of the pulse signal P1, the noise has a hexadecimal digital value “7H” as shown in FIG. Thus, the state that can be obtained is the state “JX” that does not correspond to any of “J1” to “J6”. Alternatively, when the noise N2 is superimposed, the hexadecimal digital value becomes “6H”, and the finally obtained state becomes “J5”. As a result, the rotational direction and rotational position of the motor cannot be accurately detected from these states. In such a case, it is determined that an abnormality has occurred in the motor drive circuit, the motor control by the AFS is immediately stopped, and fail safe such as fixing the swivel lamp in a straight traveling direction is executed. Therefore, although there is no particular problem with the actual AFS operation with instantaneous noise, there is a problem that the normal operation of the AFS is impaired by fail fail being executed every time noise occurs.

  An object of the present invention is to provide a vehicular illumination device including motor driving means that can accurately detect the rotation direction and rotation position of a motor without the influence of noise.

The present invention relates to a vehicle illumination device including an optical axis deflecting unit that deflects an irradiation optical axis of an illumination device provided in a vehicle, a drive motor as a rotational drive source of the optical axis deflection unit, and a rotational position of the drive motor. A plurality of detection elements for outputting a signal for detection, and motor control means for controlling the rotational operation of the drive motor based on the rotational position detected based on the signal output by the detection element, The motor control means detects an abnormality based on the adjacent state of the state signal generated based on the signal sequentially output from the detection element , and then generates based on the signal output from the detection element when the abnormality is detected. And a calculating means for calculating a rotation direction and a rotation position of the drive motor based on a normal state signal .

According to the present invention, in the calculation means, an abnormality is detected based on the adjacent state of the state signal generated based on the signals sequentially output from the detection elements, and the normal generated next when the abnormality is detected. Since the rotation direction and rotation position of the drive motor are calculated based on the state signal, noise is superimposed on the signal output from the detection element , and the rotation position and rotation direction of the motor cannot be detected normally. Even in this case, it is possible to correct the signal on which the noise is superimposed based on the next normal state signal and to accurately obtain the rotation direction and rotation position of the motor by calculation.

In the present invention, the computing means encodes the signal from each detection element to generate a state signal, and sequentially stores the state signal, means for determining the adjacent state of the stored state signal, and the determined adjacent state A state counter that increases or decreases the count value from the error state, an error counter that counts the number of errors from the determined adjacent state, and a correction circuit that corrects the count value of the state counter based on the determined adjacent state and the number of errors. It is preferable that a signal for controlling the drive motor is output based on the count value of the counter, and an error signal is output based on the count value of the error counter. In addition, it is preferable to perform correction within the rotation of the drive motor within ± 180 ° for the correction by the contract calculation means. The drive motor is preferably a three-phase brushless motor, and the detection element is preferably composed of three detection elements corresponding to the three phases. Furthermore, it is preferable that when an error signal is output, a signal for executing a fail safe for fixing the drive motor at a predetermined rotational position is output.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 2 is a longitudinal sectional view of the internal structure of the swivel lamp capable of deflecting the irradiation direction left and right among the components of the AFS described in FIG. 1, and FIG. 3 is a partially exploded perspective view of the main part thereof. A lens 12 is attached to the front opening of the lamp body 11, and a rear cover 13 is attached to the rear opening to form a lamp chamber 14. A projector lamp 30 is disposed in the lamp chamber 14. Yes. The projector lamp 30 includes a sleeve 301, a reflector 302, a lens 303, and a light source 304, which are already widely used. Therefore, a detailed description thereof will be omitted. I use what I used. The projector lamp 30 is supported by a bracket 31 having a generally U-shape. An extension 15 is disposed around the projector lamp 30 in the lamp body 11 so that the inside is not exposed through the lens 12. Further, in this embodiment, a lighting circuit 7 for lighting the discharge bulb of the projector lamp 30 using the lower cover 16 attached to the bottom opening of the lamp body 11 is provided.

  The projector lamp 30 is supported in a state of being sandwiched between a lower plate 312 and an upper plate 313 that are bent at a right angle from the vertical plate 311 of the bracket 31. An actuator 4, which will be described later, is fixed to the lower side of the lower plate 312 with a screw 314, and the rotation output shaft 411 of the actuator 4 protrudes upward through a shaft hole 315 opened in the lower plate 312. The screw 314 is screwed to a boss 318 protruding from the lower surface of the lower plate 312. A shaft portion 305 provided on the upper surface of the projector lamp 30 is fitted into a bearing 316 provided on the upper plate 313, and a connecting portion 306 provided on the lower surface of the projector lamp 30 is a rotation output shaft of the actuator 4. Thus, the projector lamp 30 can be pivoted in the left-right direction with respect to the bracket 31, and the horizontal direction integrally with the rotation output shaft 411 by the operation of the actuator 4 as will be described later. It is designed to rotate.

  Here, aiming nuts 321 and 322 are integrally attached to the left and right upper parts of the bracket 31 as viewed from the front, and leveling bearings 323 are integrally attached to the lower part of the right side. The horizontal aiming screw 331 and the vertical aiming screw 332, which are supported so as to be rotatable about the shaft, are screwed together, and the leveling ball 51 of the leveling mechanism 5 is fitted. By rotating the horizontal aiming screw 331 and the vertical aiming screw 332, the bracket 31 can be rotated in the left-right direction and the up-down direction. Further, the leveling pole 51 can be moved back and forth in the axial direction by the leveling mechanism 5, whereby the bracket 31 can be rotated in the vertical direction. Thereby, aiming adjustment for adjusting the optical axis of the projector lamp 30 in the horizontal direction and the vertical direction, and leveling adjustment for adjusting the optical axis of the projector lamp in the vertical direction in response to the leveling state accompanying the change in the vehicle height of the automobile. Is possible. A projection 307 projects from the lower surface of the reflector 302 of the projector lamp 30, and a pair of stoppers 317 are cut and raised at the left and right positions on the lower plate 312 of the bracket 31 facing the projection 307. As the lamp 30 rotates, the projection 307 comes into contact with one of the stoppers 317 so that the rotation range of the projector lamp 30 is restricted.

  The actuator 4 includes a case 41 that is close to a pentagon formed by an upper half and a lower half that are divided into upper and lower parts, and support pieces 412 and 413 are formed on both sides of the case 41 so as to protrude toward both sides. The case 41 is used to fix the case 41 to the boss 318 of the bracket 31 with a screw 314. A rotation output shaft 411 having a spline configuration protrudes from the upper surface of the case 41 and is coupled to the connecting portion 306 on the bottom surface of the projector lamp 30. The rotation output shaft 411 is reciprocatingly driven within a required rotation angle range by a brushless motor 42 described later built in the actuator 4. Further, a connector not shown in the drawing is disposed on the back surface of the case 41, and the external connector 21 connected to the ECU 2 is fitted therein.

  FIG. 4 is a block circuit diagram showing an electric circuit configuration of a lighting device including the ECU 2 and the actuator 4. The actuator 4 is mounted on the left and right swivel lamps 3R, 3L of the automobile, and is capable of bidirectional communication with the ECU 2. In the ECU 2, a main CPU 201 as a main control circuit that performs processing according to a predetermined algorithm based on the steering angle and vehicle speed detected by the steering sensor 1 </ b> A and the vehicle speed sensor 1 </ b> B and outputs a required control signal C <b> 0, An interface (hereinafter referred to as I / F) circuit 202 for inputting / outputting the control signal C0 between the main CPU 201 and the actuator 4 is provided. Here, the control signal C0 is a left / right deflection angle signal for controlling the optical axis deflection angle of the swivel lamps 3R, 3L with respect to the actuator 4.

  Further, a control circuit 43 built in the actuator 4 provided in each of the right and left swivel lamps 3R and 3L of the automobile has an I / F circuit 432 for inputting / outputting a signal to / from the ECU 2. , A sub CPU 431 that performs processing based on a predetermined algorithm based on a signal input from the I / F circuit 432, and a motor drive circuit 433 that rotationally drives the brushless motor 42 as a rotational driving means. . Here, the ECU 2 outputs the left and right deflection angle signals of the swivel lamps 3R and 3L as a part of the control signal C0 and inputs them to the actuator 4. The lighting circuit 7 for lighting the swivel lamps 3R and 3L is controlled to be turned on by the main CPU 201.

  According to the AFS configured as described above, the steering sensor 1A disposed in the car CAR detects the rotation angle of the steering wheel SW, that is, the car steering angle signal and the car speed signal from the car speed sensor 1B. And input to the ECU 2. The ECU 2 calculates the left and right deflection angle signals C0 of the projector lamp 30 in the swivel lamps 3R and 3L of the automobile based on the input detection output, and inputs them to the actuators 4 of the swivel lamps 3R and 3L. . In the actuator 4, the sub CPU 431 performs calculation based on the input left / right deflection angle signal C 0, calculates a signal corresponding to the left / right deflection angle signal C 0, outputs the signal to the motor drive circuit 433, and rotationally drives the motor 42. The rotational driving force of the motor 42 is decelerated and transmitted to the rotational output shaft 411, the projector lamp 30 connected to the rotational output shaft 411 rotates in the horizontal direction, and the irradiation direction (optical axis direction) of the swivel lamps 3R and 3L. ) Is deflected left and right.

  As shown in the perspective view in which a part of the brushless motor 42 is broken in FIG. 5, a rotary shaft 423 is provided on a hollow boss 414 erected in the case 41 of the actuator 4 by a thrust bearing and a sleeve bearing outside the figure. It is supported so that it can roll. A stator coil 424 including three pairs of coils equally distributed in the circumferential direction is fixedly supported on the hollow boss 414, and the stator coil 424 is a printed circuit board disposed in the case 41. 45 is electrically connected to supply power. Here, the stator coil 424 is integrally assembled with the core base 425, and is configured to be electrically connected to the printed circuit board 45 using a terminal 425 a provided on the core base 425. A cylindrical container-like rotor 426 is fixedly attached to the upper end of the rotating shaft 423 so as to cover the stator coil 424, and the first gear 441 is integrally attached to the upper end. Yes. The rotor 426 includes a resin-molded cylindrical container type yoke 427 and an annular rotor magnet 428 attached to the inner peripheral surface of the yoke 427 and alternately magnetized with S and N poles in the circumferential direction. It consists of and.

  Further, a plurality of, in this case, three Hall elements H1, H2, and H3, which are arranged at a predetermined interval along the circumferential direction of the rotor 426, are arrayed and supported on the printed circuit board 45, together with the rotor 426. When the rotor magnet 428 is rotated, the magnetic field in each of the hall elements H1, H2, and H3 is changed, and the on / off states of the hall elements H1, H2, and H3 are changed to change the rectangular wave corresponding to the rotation period of the rotor 426. The pulse signal P is output.

  As shown in a block circuit diagram of the brushless motor 42 and the motor drive circuit 433 in FIG. 6, the motor drive circuit 433 receives a motor rotation control signal R1 corresponding to the target rotation position of the motor from the sub CPU 431. The The motor drive circuit 433 includes a motor rotation control unit 434, a matrix circuit 435, and an output circuit 436. The motor rotation control unit 434 detects the rotation direction and the rotation position of the brushless motor 42 based on the pulse signals P (P1, P2, P3) from the three hall elements H1, H2, and H3, and uses the detected value as a detection value. Based on this, a required control signal D1 is output to the matrix circuit 435. The matrix circuit 435 outputs a motor drive control signal C1 based on the motor rotation control signal R1 and the control signal D1. The output circuit 436 supplies U, V, and W alternating currents having different phases to the three coils of the stator coil 424 of the brushless motor 42 based on the motor drive control signal C1, and thereby the rotor magnet 428 and The rotor 426 and the rotating shaft 423 are rotated.

  As shown in FIG. 7, the motor rotation control unit 434 detects the pulse signals P1, P2, and P3 and calculates a hexadecimal digital value of “1H” to “6H”, and an output of the encoder Is converted to states "J1" to "J6", and the rotational direction and rotational position of the brushless motor 42 are calculated based on the states "J1" to "J6" output from the state detection unit. A rotation calculation unit 4343 for outputting the control signal D1. In this embodiment, the rotation calculation unit 4343 is configured as a part of an IC constituting the motor rotation control unit 434. However, the rotation calculation unit 4343 may be configured using a part of the sub CPU 431.

  As shown in FIG. 9B, the encoder 4341 sets the level of each pulse signal at the rising and falling edges of the pulse signals P1, P2, and P3 output from the Hall elements H1, H2, and H3. By encoding this as a 3-bit digital value of “1” and “0”, it is converted into a hexadecimal digital value of “1H” to “6H”. Note that, when the rotation of the motor is stopped when the rising and falling edges of the pulse signal are not detected, the level of each pulse signal is detected every preset time (for example, 10 ms) and encoding is executed. As shown in FIG. 10 (c), the state detection unit 4342 has values “5H”, “1H”, “3H”, “2H”, “2H” obtained by arranging digital values from the encoder 4341 along the CW direction. “6H” and “4H” are converted to the states “J1”, “J2”, “J3”, “J4”, “J5”, and “J6”, respectively, and output.

  Referring to FIG. 7 again, the rotation calculation unit 4343 is synchronized with a timing signal generator 4344 that outputs a timing signal based on the pulse signals P1 to P3 in the encoder, and a timing signal generated by the timing signal generator 4344. Then, a shift register 4345 that sequentially stores the state signals “J1” to “J6” from the state detection unit 4342, an adjacent determination unit 4346 that compares adjacent state signals among the state signals stored in the shift register 4345, A state counter 4347 for increasing / decreasing the count value based on the comparison result of the adjacent determination unit 4346, a correction circuit 4348 for correcting the count value of the state counter 4347 based on the comparison result of the adjacent determination unit 4346, and the adjacent determination unit 4346 Error count that counts the number of errors based on comparison results And a 4349. Then, the control signal D1 is output from the state counter 4347, and an error signal E1 described later is output from the error counter 4349.

  The operation of the rotation calculation unit 4343 will be described based on the flowchart of FIG. First, the encoder 4341 generates a hexadecimal digital value when the pulse signals P1 to P3 are input, and the state detection unit 4342 converts the hexadecimal digital value into state signals “J1” to “J6”. The rotation calculation unit 4343 generates a timing signal from the timing signal generator 4344 based on the pulse signals P1 to P3, and the state signal sequentially output from the state detection unit 4342 to the shift register 4345 in synchronization with the timing signal. Store (S101). Next, the adjacency determination device 4346 takes in the adjacent state signal among the state signals stored in the shift register 4345 (S102). Then, it is determined whether or not the compared status signals are adjacent in the order of “J1” to “J6” or the reverse order (S103). If they are arranged in order, the rotational direction is determined based on the order, and “+1” is output to the state counter 4347 in the CW direction, and “−” is output to the state counter 4347 in the CCW direction. 1 "is output (S104). As a result, the count value of the state counter 4347 is incremented or decremented by “1”, so this count value becomes a count value indicating the rotational position of the motor and is output to the matrix circuit 435 as the control signal D1 as described above. The

  On the other hand, when it is determined in step S103 by the adjacency determination device 4346 that the adjacent state signals are not arranged in the correct order, the count value of the state counter 4347 is held as it is (S105). The count value of the error counter 4349 is set to “1” (S106). Then, the adjacency determination device 4346 fetches the next status signal stored in the shift register 4345 (S107), and compares the fetched next adjacent status signal (S108). In this comparison, when adjacent state signals are arranged in order, the rotation direction is determined based on the order. At the same time, correction processing is performed (S109). In this correction processing S109, the correction circuit 4348 reads the count value “1” of the error counter 4349, and in the case of the CW direction, adds the count value “1” of the error counter 4349 to “+1” and adds “+2” to the status counter. In the CCW direction, the count value “1” of the error counter 4349 is subtracted from “−1” and “−2” is output to the state counter 4347. Therefore, as shown in FIG. 9B, even when noise is superimposed and abnormality occurs in the state signal, the rotation direction and the rotation position are corrected by the state signal in which the next noise is not superimposed, and correct control is performed. It becomes possible to output the signal D1. After that, the flow after step S105 is executed.

  On the other hand, when it is determined in step S108 that adjacent state signals are not arranged in order, the uncorrectable process is performed (S110). In this uncorrectable processing, the count value of the error counter 4349 is incremented by “+1” and increased to “2” while the count value of the state counter 4347 is held as it is. Then, the count value of the error counter 4349 is compared with a predetermined value “a”, and if it is smaller than “a”, the flow after step S105 is executed again (S111). That is, the adjacent determination unit 4346 compares adjacent state signals with respect to the state signal stored next in the shift register 4345. In this comparison, when adjacent state signals are arranged in order, the rotation direction is determined based on the order. At the same time, the correction circuit 4348 reads the count value “2” of the error counter 4349. In the case of the CW direction, the count value “2” of the error counter 4349 is added to “+1” and “+3” is added to the status counter 4347. In the CCW direction, the count value “2” of the error counter 4349 is subtracted from “−1” and “−3” is output to the state counter 4347. Therefore, even when an abnormality occurs in the two status signals, it is possible to correct the rotational direction and the rotational position with the status signal in which the next noise is not superimposed and output the correct control signal D1.

  In this way, the state signals “J1” to “J6” are sequentially compared, and even when an abnormality occurs in the state signal, the state in which adjacent state signals are correctly aligned is detected, thereby correcting the rotation direction and the rotation position. It becomes possible to do. However, since there are six status signals “J1” to “J6” in the present embodiment, when three or more abnormal signals are generated continuously, or when every other signal is generated three times, the adjacent status signals The signal alignment direction cannot be determined, and correction by the correction circuit 4348 cannot be performed. That is, the correction by the calculation means is performed within the rotation of the brushless motor 42 within ± 180 °.

  Therefore, the rotational direction cannot be accurately determined, and the rotational position cannot be accurately determined. Therefore, in this embodiment, when the count value of the error counter 4349 is equal to or larger than the predetermined number “a”, here, the count value is “3”, the error signal E1 is output from the error counter 4349, and based on the error signal E1. The sub CPU 431 executes fail safe. In this fail safe, for example, control is performed to fix the rotational position of the brushless motor 42 at a position where the optical axis of the swivel lamp is fixed in the straight direction of the automobile.

  As described above, in this embodiment, when noise is superimposed in a limited range, the correction is performed quickly to determine the rotation direction and the rotation position, and normal operation is ensured. As a result, the problem that the fail safe is executed by instantaneous noise and the normal operation of the AFS is impaired can be solved.

  In the above embodiment, the AFS is applied to a headlamp that changes the irradiation optical axis by deflecting the projector lamp constituting the swivel lamp in the left-right direction. You may apply to the headlamp which changed the substantial irradiation range by carrying out the deflection | deviation operation of the structure which carries out a deflection | deviation operation | movement, or the auxiliary reflector provided independently of the main reflector.

It is a figure which shows the conceptual structure of AFS. It is a longitudinal cross-sectional view of a swivel lamp. It is a disassembled perspective view of the principal part of the internal structure of a swivel lamp. It is a block circuit diagram which shows the circuit structure of AFS. It is the disassembled perspective view which fractured | ruptured a part of brushless motor. It is a block circuit diagram of a brushless motor and a motor drive circuit. It is a block circuit diagram which shows the internal structure of a motor drive circuit. It is a flowchart for demonstrating operation | movement of the rotation calculating part of this invention. It is a figure for demonstrating the hexadecimal digital value and state which are obtained from a pulse signal.

Explanation of symbols

1A Steering sensor 1B Vehicle speed sensor 2 ECU
3 Headlamp 3R Right swivel lamp 3L Left swivel lamp 4 Actuator 30 Projector lamp 42 Swivel motor 43 Control circuit 201 Main CPU
431 Sub CPU
433 Motor drive circuit 434 Motor rotation control unit 435 Matrix circuit 436 Output circuit 4341 Encoder 4342 State detection unit 4343 Rotation calculation unit H1, H2, H3 Hall element

Claims (5)

In a vehicle illumination device including an optical axis deflection unit that deflects an irradiation optical axis of an illumination device provided in a vehicle, a drive motor as a rotational drive source of the optical axis deflection unit and a rotational position of the drive motor are detected A plurality of detection elements for outputting a signal for the control, and motor control means for controlling the rotational operation of the drive motor based on a rotational position detected based on the signal output by the detection element, the motor The control means detects an abnormality based on an adjacent state of a state signal generated based on a signal sequentially output from the detection element, and performs the next operation based on a signal output from the detection element when the abnormality is detected. A vehicle lighting device, comprising: a calculation means for calculating a rotation direction and a rotation position of the drive motor based on a normal state signal generated by the vehicle. The arithmetic means encodes signals from the detection elements to generate state signals, sequentially stores the state signals, means for determining adjacent states of the stored state signals, and counting from the determined adjacent states A state counter that increases or decreases a value, an error counter that counts the number of errors from the determined adjacent state, and a correction circuit that corrects the count value of the state counter based on the determined adjacent state and the number of errors. 2. The vehicular illumination according to claim 1, wherein a signal for controlling the drive motor is output based on a count value of a counter, and an error signal is output based on a count value of the error counter. apparatus.   The vehicle lighting device according to claim 2, wherein the correction by the calculation means is performed within a rotation of ± 180 ° of the drive motor. 4. The vehicular lighting device according to claim 2, wherein the drive motor is a three-phase brushless motor, and the detection element includes three detection elements corresponding to each phase. 5. The vehicular illumination device according to claim 2, further comprising: a fail-safe unit that fixes the drive motor at a predetermined rotational position when the error signal is output.

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