JP2014215249A - Motor control system and control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the position detecting accuracy of a control object, and to achieve accurate motor control.SOLUTION: A control device outputs a signal for rotating the drive shaft of a motor. A transmission mechanism is connected to the drive shaft, and a movable member moves in accordance with the driving force of the motor to be transmitted by the transmission mechanism. A magnet displaces in accordance with the movable member. A magnetic sensor detects magnetism generated by the magnet, and outputs a signal having a first level L1 corresponding to the first state of the magnetism and a second level L2 corresponding to the second state of the magnetism to a control device. The control device determines a rotation angle position θ1 of the drive shaft at a point of time t1 of detecting transition from the first level L1 to the second level L2 by rotating the drive shaft as the control reference position of the movable member. In the case of detecting transition from the second level L2 to the first level L1 by rotating the drive shaft, the control device determines the rotation angle position of the drive shaft at a point of time t4 of detecting transition from the first level L1 to the second level L2 by inversely rotating the drive shaft as the control reference position.

Description

  The present invention relates to an apparatus for controlling a motor having a drive shaft, and a system including the motor and the apparatus.

  A system is known in which a movable member is moved by a driving force of a motor to change a light distribution by a lamp mounted on the vehicle. The position of the movable member is detected by a magnetic sensor. The control device controls the movement of the movable member according to the output signal of the magnetic sensor (see, for example, Patent Document 1).

JP 2011-84151 A

  In order to accurately control an object, it is necessary to accurately detect the position of the object. Therefore, an object of the present invention is to provide a technique that improves the position detection accuracy of a control target and enables accurate motor control.

In order to achieve the above object, a first aspect that the present invention can take is a motor control system,
A motor having a drive shaft;
A transmission mechanism connected to the drive shaft;
A movable member that moves according to the driving force of the motor transmitted by the transmission mechanism;
A magnet that is displaced together with the movable member;
A magnetic sensor for detecting magnetism generated by the magnet;
A controller for outputting a signal for rotating the drive shaft,
The magnetic sensor outputs a signal having a first level corresponding to the first state of the magnetism and a second level corresponding to the second state of the magnetism to the control device;
The control device determines a rotation angle position of the drive shaft when the drive shaft is rotated to detect a transition from the first level to the second level as a control reference position of the movable member,
When the control device rotates the drive shaft and detects a transition from the second level to the first level, the control device reversely rotates the drive shaft to change the first level to the second level. The rotational angle position of the drive shaft when detected is determined as the control reference position.

  Due to the backlash of the transmission mechanism and the hysteresis characteristics of the magnetic sensor, the rotational angle position of the drive shaft corresponding to the position where the magnetic change is detected may differ depending on the driving direction of the motor. According to said structure, only when the output signal of a magnetic sensor changes from a 1st level to a 2nd level is used for determination of the reference position which concerns on control of a movable member. Thereby, the determined control reference position does not vary depending on the driving direction of the motor. Therefore, it is possible to accurately detect the position of the movable member as a control target and to accurately execute the rotation control.

  The control device detects the transition from the second level to the first level and then reversely rotates the drive shaft until the transition from the first level to the second level is detected. The backlash amount of the transmission mechanism may be estimated based on the rotation amount of the drive shaft. In this case, the control device corrects a signal for rotating the drive shaft based on the estimated backlash amount.

  The amount of backlash varies from product to product and varies over time. According to said structure, the value acquired at the time of determination of a control reference position can be utilized for subsequent correction processing. Therefore, the control of the movable member in accordance with the actual state of the transmission mechanism can be accurately executed without increasing the processing load.

  The controller may be configured to determine that the magnetic sensor has failed if the transition from the first level to the second level cannot be detected even if the drive shaft is rotated by a predetermined amount.

  If the magnetic sensor is out of order, this is determined when the control reference position is determined. Therefore, it is detected at an early stage that the movable member cannot be properly controlled, and appropriate measures can be taken.

  A control member configured to control the movement of the movable member, and the control device determines a rotation angle position of the drive shaft when the control member detects a control by the control member before rotating the drive shaft by the predetermined amount; It is good also as a structure defined as a position.

  In this case, it is possible to avoid a situation in which the driving of the motor is continued while the movement of the movable member is regulated by the regulating member. That is, it is possible to prevent an excessive load from being applied to the motor and the transmission mechanism due to the failure of the magnetic sensor, and the failure to reach these.

  The movable member may be a member that changes light distribution by a lamp mounted on a vehicle.

  In this case, it is possible to avoid a situation where glare is given to the vehicle ahead based on inaccurate light distribution control, or a situation where necessary illumination is insufficient.

In order to achieve the above object, a second aspect of the present invention is a motor control device having a drive shaft,
A receiver for receiving an output signal from the magnetic sensor;
An output unit for outputting a signal for rotating the drive shaft,
The output signal has a first level corresponding to a magnetic first state and a second level corresponding to the magnetic second state;
The rotation angle position of the drive shaft when the drive shaft is rotated to detect a transition from the first level to the second level is defined as a control reference position,
When the transition from the second level to the first level is detected by rotating the drive shaft, the transition from the first level to the second level is detected by reversely rotating the drive shaft. The rotational angle position of the drive shaft is determined as the control reference position.

1 is a diagram schematically showing an overall configuration of a vehicle equipped with a motor control system according to an embodiment of the present invention. It is a disassembled perspective view which shows the structure of the lamp unit with which said motor control system is provided. It is a figure which shows the internal structure of the lamp main body with which said lamp unit is provided. It is a figure which shows the positional relationship of the magnet with which said lamp body is provided, and a magnetic sensor. It is a figure explaining the process which the control apparatus with which said motor control system is provided performs. It is a figure which shows the internal structure of the actuator with which said lamp unit is provided. It is a figure which shows the positional relationship of the magnet with which said actuator is provided, and a magnetic sensor. It is a flowchart explaining the process which said control apparatus performs.

  Exemplary embodiments according to the present invention will be described in detail below with reference to the accompanying drawings. In each drawing used in the following description, the scale is appropriately changed to make each member a recognizable size. In addition, the directions of “left / right”, “front / rear”, and “up / down” used in the following description indicate directions viewed from the driver's seat.

  FIG. 1 is a diagram schematically illustrating an overall configuration of a vehicle 2 on which a motor control system 1 according to an embodiment is mounted. The motor control system 1 includes an integrated control unit 4, a steering angle sensor 5, a vehicle height sensor 6, a camera 7, and a headlamp device 10.

  The integrated control unit 4 includes a CPU that executes various arithmetic processes, a ROM that stores various control programs, a RAM that is used as a work area for data storage and program execution, and executes various controls in the vehicle 2.

  The steering angle sensor 5 is provided on the steering wheel and is communicably connected to the integrated control unit 4. The steering angle sensor 5 outputs a signal corresponding to the steering rotation angle of the steering wheel by the driver to the integrated control unit 4. The integrated control unit 4 specifies the traveling direction of the vehicle 2 using the signal input from the steering angle sensor 5.

  The vehicle height sensor 6 is provided near the rear wheel of the vehicle 2 and is communicably connected to the integrated control unit 4. The vehicle height sensor 6 outputs a signal corresponding to the vehicle height of the vehicle 2 that changes according to the weight of the occupant or the luggage to the integrated control unit 4. The integrated control unit 4 specifies the pitch angle of the vehicle 2 (inclination in the longitudinal direction of the vehicle) using the signal input from the vehicle height sensor 6.

  The camera 7 includes an imaging element such as a CCD (Charged Coupled Device) sensor or a CMOS (Complementary Metal Oxide Semiconductor) sensor, and shoots the front of the vehicle to generate image data. The camera 7 is communicably connected to the integrated control unit 4, and the generated image data is output to the integrated control unit 4.

  The headlamp device 10 is disposed at the front end of the vehicle 2. The headlamp device 10 includes a housing 11, a translucent cover 12, and a lamp unit 20. The translucent cover 12 is attached to the housing 11 to partition the lamp chamber 13. The lamp unit 20 is accommodated in the lamp chamber 13.

  As shown in FIG. 2, the lamp unit 20 includes a lamp body 30, an actuator 40, and a bracket 50. A projection lens 31 is held at the front of the lamp body 30.

  A bearing portion 32 is provided at the lower portion of the lamp body 30. A rotating shaft 33 is provided on the upper part of the lamp body 30. The bearing portion 32 and the rotation shaft 33 are coaxial. On the other hand, a rotation shaft 41 is provided on the upper surface of the actuator 40. By fitting the rotation shaft 41 to the bearing portion 32, the lamp body 30 can be rotated around an axis shared by the bearing portion 32 and the rotation shaft 33.

  On the left and right sides of the actuator 40, protrusions 42 are formed. On the other hand, guide grooves 51 and 52 are formed in the lower portion of the bracket 50. A bearing portion 53 is provided on the upper portion of the bracket 50. The protrusion 42 and the rotation shaft 41 of the actuator 40 are inserted into the guide grooves 51 and 52 of the bracket 50, respectively, and the rotation shaft 33 of the lamp body 30 is inserted into the bearing portion 53 of the bracket 50. The lamp body 30 and the actuator 40 are assembled to the bracket 50. At this time, the rotation shaft 33 can be rotated around the shaft in the bearing portion 53 and can be tilted in the front-rear direction. The bracket 50 is fixed in the lamp chamber 13.

  As shown in FIG. 3A, the lamp body 30 includes a light source 34, a heat sink 35, a reflector 36, a rotary shade 37, a motor 38, and a transmission mechanism 39.

  The light source 34 is a semiconductor light emitting element such as a white light emitting diode (LED) or an organic EL element. The light source 34 is fixed with respect to the heat sink 35. The heat sink 35 is made of a material and shape suitable for dissipating heat emitted from the light source 34. The light emitted from the light source 34 is reflected by the reflector 36. At least a part of the light passes through the projection lens 31 disposed in front of the reflector 36.

  The reflector 36 has a reflecting surface based on a substantially elliptical spherical surface with the optical axis A1 of the projection lens 31 extending in the front-rear direction of the vehicle 2 as the central axis. The light source 34 is disposed at the first focal point of an ellipse that constitutes the vertical cross section of the reflecting surface. Thereby, the light emitted from the light source 34 is configured to converge to the second focal point of the ellipse.

  As shown in FIG. 3B, the projection lens 31 is a plano-convex aspheric lens having a convex front surface and a flat rear surface. The projection lens 31 is arranged so that the rear focal point F coincides with the second focal point of the reflecting surface of the reflector 36, and is configured to project an image on the rear focal point F as a reverse image in front of the projection lens 31. ing.

  The rotary shade 37 is disposed behind the projection lens 31 so as to block part of the light emitted from the light source 34. The rotary shade 37 has a rotation axis A <b> 2, and the rotation axis A <b> 2 is disposed so as to pass below the rear focal point F of the projection lens 31. The end of the rotary shade 37 on the right side in the axial direction is supported by the lamp body 30 by a bearing mechanism (not shown).

  The motor 38 is disposed in the vicinity of the end of the rotary shade 37 on the left side in the axial direction. The motor 38 has a drive shaft 38a. The transmission mechanism 39 has a first gear 39a and a second gear 39b. The first gear 39a meshes with the drive shaft 38a. The second gear 39b is coupled to the left end of the rotary shade 37 in the axial direction, and meshes with the second gear 39b. The motor 38 and the transmission mechanism 39 rotate the rotary shade 37 around the rotation axis A2.

  At the angular position shown in FIG. 3A, the edge 37a of the rotary shade 37 is disposed at the rear focal point F of the projection lens 31, so that the shape of the edge 37a shown in FIG. Projected in front of the lens 31. The light passing above the edge 37a illuminates below the projected image of the edge 37a. That is, the projected image of the edge 37a corresponds to a so-called low beam pattern cut-off line.

  The angular position shown in FIG. 3B is a state in which the rotary shade 37 is rotated about 90 degrees forward from the angular position shown in FIG. In this state, the light emitted from the light source 34 and reflected by the reflector 36 passes through the projection lens 31 without being blocked by the rotary shade 37. Therefore, a so-called high beam pattern is formed in front of the projection lens 31.

  The integrated control unit 4 of the vehicle 2 is connected so as to be communicable with the motor 38. The integrated control unit 4 generates a control signal for switching the light distribution pattern according to the beam switching operation by the driver or according to the detection result of the vehicle ahead by the camera 7. The motor 38 is driven according to the generated signal, and the rotary shade 37 is rotated through the transmission mechanism 39 at an angle and a direction according to the signal. That is, the rotary shade 37 functions as a member that changes the light distribution by the lamp unit 20.

  As shown in FIG. 4A, the magnet 60 is attached to the second gear 39 b of the transmission mechanism 39. A magnetic sensor 61 such as a Hall element is disposed at a position facing the magnet 60. The magnet 60 has an N-pole region and an S-pole region. As shown in FIG. 4B, a part of the magnet 60 located in front of the magnetic sensor 61 changes between the N-pole region and the S-pole region according to the rotation angle position of the second gear 39b. To do. Thus, the magnetism changing is detected by the magnetic sensor 61. The magnetic sensor 61 generates a signal corresponding to the detected magnetism and outputs the signal to the integrated control unit 4 of the vehicle 2.

  For example, as shown in FIG. 5A, output signals of level L1 corresponding to magnetism in the south pole region and level L2 corresponding to magnetism in the north pole region are output from the magnetic sensor 61. In the figure, in the initial state, the south pole region of the magnet 60 faces the magnetic sensor 61, and a signal of level L1 is output. When the drive shaft 38a of the motor 38 rotates to the angular position θ1, the rotary shade 37 (second gear 39b) rotates, and a part of the magnet 60 facing the magnetic sensor 61 changes from the S-pole region to the N-pole region. Accordingly, the output signal level transitions from L1 to L2.

  The integrated control unit 4 of the vehicle 2 determines the rotation angle position of the drive shaft 38 a when the output signal level from the magnetic sensor 61 transitions as the reference position for controlling the rotary shade 37. In the subsequent processing, the rotation direction and rotation angle of the rotary shade 37 are determined based on the reference position.

  FIG. 5B shows a case where the N pole region of the magnet 60 faces the magnetic sensor 61 in the initial state, and a level L2 signal is output. When the drive shaft 38a of the motor 38 is rotated in the opposite direction to that shown in FIG. 5A from this state, the output signal level changes from L2 to L1 when the drive shaft 38a is at the angular position θ2.

  The angular position θ2 is different from the angular position θ1. This difference is mainly due to the backlash of the transmission mechanism 39 and the hysteresis characteristics of the magnetic sensor 61. That is, there is a difference in the control reference position defined by the integrated control unit 4 between when the motor 38 is driven CW and when it is driven CCW.

  Therefore, in this embodiment, only when the output signal level transitions from L1 to L2 is used for determining the control reference position. In FIG. 5C, the solid line indicates the case where the motor 38 is driven by CW, and the broken line indicates the case where the motor 38 is driven by CCW.

  When the signal level output from the magnetic sensor 61 is L1, the integrated control unit 4 outputs a signal for CW driving the motor 38. When the CW drive is continued, as shown in FIG. 5A, the output signal level of the magnetic sensor 61 changes from L1 to L2 at a certain time t1. The integrated control unit 4 determines the angular position θ1 of the drive shaft 38a at the time t1 as the control reference position of the rotary shade 37, and stops driving the motor 38.

  On the other hand, the integrated control unit 4 outputs a signal for CCW driving the motor 38 when the signal level output from the magnetic sensor 61 is L2. If the CCW drive is continued, as shown in FIG. 5B, the output signal level of the magnetic sensor 61 changes from L2 to L1 at a certain time t2. However, the integrated control unit 4 continues the CCW drive of the motor 38 so that the drive shaft 38a is driven by a predetermined angle (θ2-θ0) from the time point t2.

  Thereafter, the integrated control unit 4 drives the motor 38 in CW to reversely rotate the drive shaft 38a (time point t3). If the CW drive is continued, as shown in FIG. 5A, the output signal level of the magnetic sensor 61 changes from L1 to L2 at a certain time t4. The integrated control unit 4 determines the angular position θ1 of the drive shaft 38a at the time t4 as the control reference position of the rotary shade 37, and stops driving the motor 38.

  Further, the integrated control unit 4 detects the angular position θ2 of the drive shaft 38a at the time t2 when the transition from the signal level L2 to L1 is detected, and the angular position of the drive shaft 38a at the time t4 when the transition from the signal level L1 to L2 is detected. The difference Δθ of θ1 is estimated as the backlash amount of the transmission mechanism 39. In the subsequent rotation control of the rotary shade 37, the signal for driving the motor 38 is corrected as necessary based on the estimated backlash amount.

  The process for determining the control reference position is based on the premise that the magnetic sensor 61 is operating normally. Therefore, the integrated control unit 4 determines that the magnetic sensor 61 has failed if the transition of the output signal level cannot be detected even when the drive shaft 38a of the motor 38 is rotated by a predetermined amount.

  Specifically, if the level transition of the output signal from the magnetic sensor 61 cannot be detected even if the drive shaft 38a is rotated by the amount by which the second gear 39b of the transmission mechanism 39 is rotated by 180 degrees, the magnetic sensor 61 has failed. It is judged that This is because if the second gear 39b is rotated 180 degrees, the N pole and S pole of the mounted magnet 60 are always reversed. When a failure of the magnetic sensor 61 is determined, the integrated control unit 4 performs an appropriate error process to notify the driver of the failure.

  As described above, the motor 38 has the drive shaft 38a. The transmission mechanism 39 is connected to the drive shaft 38a. The rotary shade 37 (an example of a movable member) moves according to the driving force of the motor 38 transmitted by the transmission mechanism 39. The magnet 60 is displaced together with the rotary shade 37. The magnetic sensor 61 detects the magnetism generated by the magnet 60, and has a level L1 (an example of the first level) and an N pole (an example of the second magnetic state) corresponding to the S pole (an example of the first magnetic state). ) Is output to the integrated control unit 4 (an example of a control device) of the vehicle 2.

  The integrated control unit 4 outputs a signal for rotating the drive shaft 38 a, and determines the rotation angle position of the drive shaft 38 a when the output signal level of the magnetic sensor 61 transitions from L 1 to L 2. Determined as the control reference position. Further, when the integrated control unit 4 rotates the drive shaft 38a and detects the transition from the signal level L2 to L1, the integrated control unit 4 rotates the drive shaft 38a in the reverse direction and detects the transition from the signal level L1 to L2. The rotational angle position of the shaft 38 a is determined as the control reference position of the rotary shade 37.

  That is, only when the output signal level of the magnetic sensor 61 transitions from L1 to L2, it is used to determine the reference position related to the control of the rotary shade 37. The control reference position determined in this way does not vary depending on the initial drive direction of the motor 38. Therefore, the rotation control of the rotary shade 37 can be executed accurately.

  The integrated control unit 4 detects the amount of rotation Δθ of the drive shaft 38a from when the transition from the signal level L2 to L1 is detected until the drive shaft 38a is reversely rotated to detect the transition from the signal level L1 to L2. Based on this, the backlash amount of the transmission mechanism 39 is estimated. The integrated control unit 4 corrects the signal for rotating the drive shaft 38a based on the estimated backlash amount.

  The amount of backlash varies from product to product and varies over time. According to said structure, the value acquired at the time of determination of a control reference position can be utilized for subsequent correction processing. Therefore, the rotation control of the rotary shade 37 in accordance with the actual state of the transmission mechanism 39 can be accurately executed without increasing the processing load.

  The integrated control unit 4 determines that the magnetic sensor 61 has failed when the transition of the output signal level cannot be detected even when the drive shaft 38a is rotated by a predetermined amount.

  If the magnetic sensor 61 is out of order, this is determined when the control reference position is determined. Therefore, it is detected early that the rotation control of the rotary shade 37 cannot be properly performed, and appropriate measures can be taken. it can.

  The rotary shade 37 is a member that changes the light distribution by the lamp unit 20 mounted on the vehicle 2. Therefore, it is possible to avoid a situation where glare is given to the vehicle ahead based on inaccurate light distribution control or a situation where necessary illumination is insufficient.

  FIG. 6 schematically shows the internal structure of the actuator 40. The actuator 40 includes a first motor 43, a first transmission mechanism 44, a sector gear 45, a stopper 46, a second motor 47, a second transmission mechanism 48, and a pinion gear 49.

  The first motor 43 has a drive shaft 43a. The first transmission mechanism 44 includes a first gear 44a, a second gear 44b, and a third gear 44c. The drive shaft 43a meshes with the first gear 44a. The first gear 44a meshes with the second gear 44b. The second gear 44b meshes with the third gear 44c. The third gear 44c meshes with the sector gear 45. The sector gear 45 is coupled to the rotating shaft 41 described with reference to FIG. The stopper 46 includes a right stopper 46a and a left stopper 46b, and restricts the movement range of the sector gear 45.

  The integrated control unit 4 of the vehicle 2 is connected to be communicable with the first motor 43. When the driver operates the steering wheel, the integrated control unit 4 specifies the traveling direction of the vehicle 2 according to the output of the steering angle sensor 5. The integrated control unit 4 generates a control signal corresponding to the specified traveling direction, and rotates the drive shaft 43 a of the first motor 43. The rotation of the drive shaft 43 a is transmitted to the sector gear 45 through the first transmission mechanism 44. As the sector gear 45 is displaced, the rotation shaft 41 rotates in the left-right direction. Thereby, the optical axis A1 of the projection lens 31 shown in FIG. 2 is displaced in the left-right direction.

  That is, the actuator 40 functions as a so-called swivel actuator that changes the light distribution by the lamp unit 20 in the left-right direction. The integrated control unit 4 controls the driving of the first motor 43 so that the optical axis A1 is displaced rightward when the vehicle 2 is turning right, and the optical axis A1 is displaced leftward when the vehicle 2 is turning left.

  The second motor 47 has a drive shaft 47a. The second transmission mechanism 48 includes a first gear 48a, a second gear 48b, and a third gear 48c. The drive shaft 47a meshes with the first gear 48a. The first gear 48a meshes with the second gear 48b. The second gear 48b meshes with the third gear 48c. The third gear 48 c meshes with the pinion gear 49. As indicated by a broken line in FIG. 6, the bracket 50 includes a rack 54, a front stopper 55a, and a rear stopper 55b. The pinion gear 49 meshes with the rack 54. The front stopper 55a and the rear stopper 55b regulate the movement range of the pinion gear 49.

  The integrated control unit 4 of the vehicle 2 is connected to be communicable with the second motor 47. The integrated control unit 4 specifies the pitch angle of the vehicle 2 according to the output of the vehicle height sensor 6. The integrated control unit 4 generates a control signal corresponding to the identified pitch angle, and rotates the drive shaft 47a of the second motor 47. The rotation of the drive shaft 47 a is transmitted to the pinion gear 49 via the second transmission mechanism 48. As the pinion gear 48 rotates, the rotation shaft 41 is displaced in the guide groove 52 in the front-rear direction.

  As shown in FIG. 2, since the rotation shaft 33 provided on the upper part of the lamp body 30 is held by the bearing portion 53 of the bracket 50, the lamp body 30 tilts in the vertical direction. As a result, the optical axis A1 of the projection lens 31 is displaced in the vertical direction.

  That is, the actuator 40 functions as a so-called leveling actuator that changes the light distribution by the lamp unit 20 in the vertical direction. The integrated control unit 4 controls the driving of the second motor 47 so that the actuator 40 is displaced rearward as the vehicle height of the vehicle 2 decreases. The optical axis A1 is displaced downward as the actuator 40 moves rearward.

  As shown in FIG. 7, a magnet 70 is attached to the third gear 44 c of the first transmission mechanism 44. A magnetic sensor 71 such as a Hall element is disposed at a position facing the magnet 70. The magnet 70 has an N pole region and an S pole region. Depending on the rotation angle position of the third gear 44b, a part of the magnet 70 located in front of the magnetic sensor 71 changes between the N-pole region and the S-pole region. Thus, the magnetism changing is detected by the magnetic sensor 71. The magnetic sensor 71 generates a signal corresponding to the detected magnetism and outputs the signal to the integrated control unit 4 of the vehicle 2.

  As in the case of the magnetic sensor 61 described with reference to FIG. 5, the output signal of the level L1 corresponding to the magnetism in the south pole region and the level L2 corresponding to the magnetism in the north pole region is output from the magnetic sensor 71. The The integrated control unit 4 determines the rotation angle position of the drive shaft 43a when the output signal level from the magnetic sensor 71 transits from L1 to L2 as a reference position for swivel control by the actuator 40. In the subsequent processing, the rotation direction and rotation angle of the rotation shaft 41 are determined based on the reference position.

  When the signal level output from the magnetic sensor 71 is L1, the integrated control unit 4 outputs a signal for CW driving the first motor 43. If the CW drive is continued, the output signal level of the magnetic sensor 71 changes from L1 to L2 at a certain time t1, as shown in FIG. The integrated control unit 4 determines the angular position θ1 of the drive shaft 43a at the time point t1 as a reference position related to swivel control of the optical axis A1, and stops driving the first motor 43.

  On the other hand, when the signal level output from the magnetic sensor 71 is L2, the integrated control unit 4 outputs a signal for CCW driving the first motor 43. If the CCW drive is continued, as shown in FIG. 5B, the output signal level of the magnetic sensor 71 changes from L2 to L1 at a certain time t2. However, the integrated control unit 4 continues the CCW drive of the first motor 43 so that the drive shaft 43a is driven by a predetermined angle (θ2-θ0) from the time point t2.

  Thereafter, the integrated control unit 4 drives the first motor 43 by CW to reversely rotate the drive shaft 43a (time point t3). If the CW drive is continued, as shown in FIG. 5A, the output signal level of the magnetic sensor 71 changes from L1 to L2 at a certain time t4. The integrated control unit 4 determines the angular position θ1 of the drive shaft 43a at the time point t4 as a reference position for swivel control of the optical axis A1, and stops driving the first motor 43.

  The integrated control unit 4 also detects the angular position θ2 of the drive shaft 43a at the time t2 when the transition from the signal level L2 to L1 is detected, and the angular position of the drive shaft 43a at the time t4 when the transition from the signal level L1 to L2 is detected. The difference Δθ of θ1 is estimated as the backlash amount of the first transmission mechanism 44. In the subsequent swivel control of the optical axis A1, the signal for driving the first motor 43 is corrected as necessary based on the estimated backlash amount.

  The process for determining the control reference position is based on the assumption that the magnetic sensor 71 is operating normally. Therefore, the integrated control unit 4 determines that the magnetic sensor 71 is out of order if the transition of the output signal level cannot be detected even when the drive shaft 43a of the first motor 43 is rotated by a predetermined amount.

  Processing executed by the integrated control unit 4 at this time will be described with reference to FIG. First, it is determined whether or not a transition is detected for the output signal level of the magnetic sensor 71 (step S1). When the transition is detected (Yes in step S1), the control reference position is determined based on the above process (step S4).

  If no transition of the output signal level is detected (No in step S1), it is determined whether or not the rotation amount of the drive shaft 43a is equal to or greater than a predetermined value (step S2). Here, the predetermined value is the amount of rotation of the drive shaft 43a that is displaced from the position where the right end 45a of the sector gear 45 contacts the right stopper 46a to the position where the left end 45b of the sector gear contacts the left stopper 46b in FIG. Determined. In other words, the arrangement of the magnets 70 is determined such that the boundary between the N pole and the S pole is always detected by the magnetic sensor 71 while the sector gear 45 is displaced by the above amount.

  When the rotation amount of the drive shaft 43a is equal to or greater than the predetermined value (Yes in step S2), that is, when the sector gear 45 reaches the allowable movement amount without detecting the transition of the output signal level of the magnetic sensor 71, The integrated control unit 4 determines that the magnetic sensor 71 is out of order and executes predetermined error processing (step S5).

  When a motor that does not use an absolute position sensor such as a stepping motor or a brushless motor is used as the first motor 43, information on the control reference position is lost every time the power supply is cut off. Therefore, it is necessary to reset the reference position. At this time, depending on the initial position of the sector gear 45, the sector gear 45 may come into contact with the stopper 46 before the drive shaft 43a is rotated by the predetermined amount. For example, the initial position of the left end 45b of the sector gear 45 is immediately before the left stopper 46b, and the drive shaft 43a is rotated so that the sector gear 45 is displaced to the left.

  Therefore, when the drive amount is less than the predetermined value (No in step S2), the integrated control unit 4 determines whether the movement of the sector gear 45 is restricted by the stopper 46 (step S3). Until the restriction is detected (No in step S3), the determination related to the drive amount (step S2) and the determination related to the restriction (step S3) are repeated. When the restriction is detected (Yes in step S3), the angular position of the drive shaft 43a at the time when the restriction is detected is determined as the control reference position regardless of the output signal level of the magnetic sensor 71 (step S4). In the subsequent processing, the rotation direction and the rotation amount of the rotation shaft 41 are determined based on the control reference position.

  As described above, the first motor 43 has the drive shaft 43a. The first transmission mechanism 44 is connected to the drive shaft 43a. A rotation shaft 41 (an example of a movable member) of the actuator 40 moves according to the driving force of the first motor 43 transmitted by the first transmission mechanism 44. The magnet 70 is displaced together with the rotation shaft 41. The magnetic sensor 71 detects magnetism generated by the magnet 70, and corresponds to an S pole (an example of a first magnetic state), a level L1 (an example of a first level), and an N pole (an example of a second magnetic state). ) Is output to the integrated control unit 4 (an example of a control device) of the vehicle 2.

  The integrated control unit 4 outputs a signal for rotating the drive shaft 43a, and the rotation angle position of the drive shaft 43a when detecting that the output signal level of the magnetic sensor 71 has transitioned from L1 to L2 is determined as the rotation shaft 41. The control reference position is determined. Further, when the integrated control unit 4 rotates the drive shaft 43a and detects a transition from the signal level L2 to L1, the integrated control unit 4 rotates the drive shaft 43a in the reverse direction and detects the transition from the signal level L1 to L2. The rotation angle position of the shaft 43a is determined as the control reference position of the rotation shaft 41.

  That is, only when the output signal level of the magnetic sensor 71 transitions from L1 to L2 is used for determination of the reference position for swivel control of the optical axis A1 of the projection lens 31. Thereby, the determined control reference position does not differ depending on the initial drive direction of the first motor 43. Therefore, the rotation control of the rotation shaft 41 can be executed accurately.

  The integrated control unit 4 detects the amount of rotation Δθ of the drive shaft 43a from when the transition from the signal level L2 to L1 is detected until the drive shaft 43a is reversely rotated to detect the transition from the signal level L1 to L2. Based on this, the backlash amount of the first transmission mechanism 44 is estimated. The integrated control unit 4 corrects the signal for rotating the drive shaft 43a based on the estimated backlash amount.

  The amount of backlash varies from product to product and varies over time. According to said structure, the value acquired at the time of determination of a control reference position can be utilized for subsequent correction processing. Therefore, the rotation control of the rotation shaft 41 in accordance with the actual state of the first transmission mechanism 44 can be accurately executed without increasing the processing load.

  If the integrated control unit 4 cannot detect the transition of the output signal level even if the drive shaft 43a is rotated by a predetermined amount, the integrated control unit 4 determines that the magnetic sensor 71 has failed.

  If the magnetic sensor 71 is out of order, this is determined when the control reference position is determined. Therefore, it is discovered at an early stage that the rotation control of the rotation shaft 41 cannot be performed properly, and appropriate measures are taken. Can do.

  The stopper 46 (an example of a regulating member) regulates the movement of the rotating shaft 41. The integrated control unit 4 determines the rotational angle position of the drive shaft 43a when the restriction by the stopper 46 is detected before rotating the drive shaft 43a by a predetermined amount as the control reference position.

  In this case, it is possible to avoid a situation in which the driving of the first motor 43 is continued while the movement of the rotation shaft 41 is restricted by the stopper 46. That is, it is possible to prevent an excessive load from being applied to the first motor 43 and the first transmission mechanism 44 due to the failure of the magnetic sensor 71 and the failure to reach them.

  The rotation shaft 41 of the actuator 40 is a member that changes the light distribution by the lamp unit 20 mounted on the vehicle 2. Therefore, it is possible to avoid a situation where glare is given to the vehicle ahead based on inaccurate light distribution control or a situation where necessary illumination is insufficient.

  As shown in FIG. 7, a magnet 80 is attached to the third gear 48 c of the second transmission mechanism 48. A magnetic sensor 81 such as a Hall element is disposed at a position facing the magnet 80. The magnet 80 has an N-pole region and an S-pole region. Depending on the relative position of the rack 54 and the third gear 44b, a part of the magnet 80 located in front of the magnetic sensor 81 changes between the N-pole region and the S-pole region. Thus, the magnetism changing is detected by the magnetic sensor 81. The magnetic sensor 81 generates a signal corresponding to the detected magnetism and outputs the signal to the integrated control unit 4 of the vehicle 2.

  As in the case of the magnetic sensor 61 described with reference to FIG. 5, the output signal of the level L1 corresponding to the magnetism in the south pole region and the level L2 corresponding to the magnetism in the north pole region is output from the magnetic sensor 81. The The integrated control unit 4 determines the rotation angle position of the drive shaft 47a when the output signal level from the magnetic sensor 81 transits from L1 to L2 as a reference position for leveling control by the actuator 40. In the subsequent processing, the displacement direction and the displacement amount of the rotation shaft 41 are determined based on the reference position.

  When the signal level output from the magnetic sensor 81 is L1, the integrated control unit 4 outputs a signal for CW driving the second motor 47. When the CW drive is continued, as shown in FIG. 5A, the output signal level of the magnetic sensor 81 changes from L1 to L2 at a certain time t1. The integrated control unit 4 determines the angular position θ1 of the drive shaft 47a at the time point t1 as a reference position related to the leveling control of the optical axis A1, and stops the driving of the second motor 47.

  On the other hand, when the signal level output from the magnetic sensor 81 is L2, the integrated control unit 4 outputs a signal for CCW driving the second motor 47. If the CCW drive is continued, as shown in FIG. 5B, the output signal level of the magnetic sensor 81 changes from L2 to L1 at a certain time t2. However, the integrated control unit 4 continues the CCW drive of the second motor 47 so that the drive shaft 47a is driven by a predetermined angle (θ2−θ0) from the time point t2.

  Thereafter, the integrated control unit 4 drives the second motor 47 in CW to reversely rotate the drive shaft 47a (time point t3). When the CW drive is continued, as shown in FIG. 5A, the output signal level of the magnetic sensor 81 changes from L1 to L2 at a certain time t4. The integrated control unit 4 determines the angular position θ1 of the drive shaft 47a at the time point t4 as a reference position related to leveling control of the optical axis A1, and stops driving the second motor 47.

  The integrated control unit 4 also detects the angular position θ2 of the drive shaft 47a at the time t2 when the transition from the signal level L2 to L1 is detected, and the angular position of the drive shaft 47a at the time t4 when the transition from the signal level L1 to L2 is detected. The difference Δθ of θ1 is estimated as the backlash amount of the second transmission mechanism 48. In the subsequent leveling control of the optical axis A1, the signal for driving the second motor 47 is corrected as necessary based on the estimated backlash amount.

  The process for determining the control reference position is based on the premise that the magnetic sensor 81 is operating normally. Therefore, the integrated control unit 4 determines that the magnetic sensor 81 is out of order if the transition of the output signal level cannot be detected even when the drive shaft 47a of the second motor 47 is rotated by a predetermined amount.

  Processing executed by the integrated control unit 4 at this time will be described with reference to FIG. First, it is determined whether or not a transition is detected for the output signal level of the magnetic sensor 81 (step S1). When the transition is detected (Yes in step S1), the control reference position is determined based on the above process (step S4).

  If no transition of the output signal level is detected (No in step S1), it is determined whether or not the amount of rotation of the drive shaft 47a is greater than or equal to a predetermined value (step S2). Here, the predetermined value is the rotation of the drive shaft 47a that is displaced from the position where the front end of the pinion gear 49 contacts the front stopper 55a in FIG. 7 to the position where the rear end of the pinion gear 49 contacts the rear stopper 55b. Determined as a quantity. In other words, the arrangement of the magnets 80 is determined such that the boundary between the N pole and the S pole is always detected by the magnetic sensor 81 while the pinion gear 49 is displaced by the above amount.

  When the rotation amount of the drive shaft 47a is equal to or greater than the predetermined value (Yes in step S2), that is, when the pinion gear 49 has reached the allowable movement amount without detecting the transition of the output signal level of the magnetic sensor 81. The integrated control unit 4 determines that the magnetic sensor 81 is out of order and executes predetermined error processing (step S5).

  When a motor that does not use an absolute position sensor such as a stepping motor or a brushless motor is used as the second motor 47, information on the control reference position is lost every time the power supply is cut off. Therefore, it is necessary to reset the reference position. At this time, depending on the initial position of the pinion gear 49, the pinion gear 49 may come into contact with the front stopper 55a or the rear stopper 55b before the drive shaft 47a is rotated by the predetermined amount. For example, the initial position of the rear end portion of the pinion gear 49 is immediately before the rear stopper 55b, and the drive shaft 47a is rotated so that the pinion gear 49 is displaced rearward.

  Therefore, when the driving amount is less than the predetermined value (No in step S2), the integrated control unit 4 determines whether the movement of the pinion gear 49 is restricted by the front stopper 55a or the rear stopper 55b (step S3). Until the restriction is detected (No in step S3), the determination related to the drive amount (step S2) and the determination related to the restriction (step S3) are repeated. When the restriction is detected (Yes in step S3), the angular position of the drive shaft 47a at the time when the restriction is detected is determined as the control reference position regardless of the output signal level of the magnetic sensor 81 (step S4). In the subsequent processing, the displacement direction and the displacement amount of the rotation shaft 41 are determined based on the control reference position.

  As described above, the second motor 47 has the drive shaft 47a. The second transmission mechanism 48 is connected to the drive shaft 47a. A rotation shaft 41 (an example of a movable member) of the actuator 40 moves according to the driving force of the second motor 47 transmitted by the second transmission mechanism 48. The magnet 80 is displaced together with the rotation shaft 41. The magnetic sensor 81 detects magnetism generated by the magnet 80, and corresponds to the level L1 (an example of the first level) corresponding to the S pole (an example of the first state of magnetism) and the N pole (an example of the second state of magnetism). ) Is output to the integrated control unit 4 (an example of a control device) of the vehicle 2.

  The integrated control unit 4 outputs a signal for rotating the drive shaft 47a, and determines the rotation angle position of the drive shaft 47a when detecting that the output signal level of the magnetic sensor 81 has transitioned from L1 to L2. The control reference position is determined. Further, when the integrated control unit 4 rotates the drive shaft 47a and detects a transition from the signal level L2 to L1, the integrated control unit 4 rotates the drive shaft 47a in the reverse direction and detects the transition from the signal level L1 to L2. The rotation angle position of the shaft 47a is determined as the control reference position of the rotation shaft 41.

  That is, only when the output signal level of the magnetic sensor 81 transits from L1 to L2, it is used to determine the reference position for leveling control of the optical axis A1 of the projection lens 31. Thereby, the determined control reference position does not differ depending on the initial drive direction of the second motor 47. Therefore, the movement control of the rotation shaft 41 can be executed accurately.

  The integrated control unit 4 detects the amount of rotation Δθ of the drive shaft 47a from when the transition from the signal level L2 to L1 is detected until the drive shaft 47a is reversely rotated to detect the transition from the signal level L1 to L2. Based on this, the backlash amount of the second transmission mechanism 48 is estimated. The integrated control unit 4 corrects the signal for rotating the drive shaft 47a based on the estimated backlash amount.

  The amount of backlash varies from product to product and varies over time. According to said structure, the value acquired at the time of determination of a control reference position can be utilized for subsequent correction processing. Therefore, the movement control of the rotation shaft 41 according to the actual state of the second transmission mechanism 48 can be accurately executed without increasing the processing load.

  The integrated control unit 4 determines that the magnetic sensor 81 has failed when the transition of the output signal level cannot be detected even when the drive shaft 47a is rotated by a predetermined amount.

  If the magnetic sensor 81 is out of order, this is determined when the control reference position is determined. Therefore, it is discovered at an early stage that the movement control of the rotation shaft 41 cannot be properly performed, and appropriate measures are taken. Can do.

  The front stopper 55a and the rear stopper 55b (an example of a restricting member) restrict the movement of the rotating shaft 41. The integrated control unit 4 determines the rotation angle position of the drive shaft 47a when the restriction by the front stopper 55a or the rear stopper 55b is detected before rotating the drive shaft 47a by a predetermined amount as the control reference position.

  In this case, it is possible to avoid a situation in which the driving of the second motor 47 is continued while the movement of the rotating shaft 41 is restricted by the front stopper 55a or the rear stopper 55b. That is, it is possible to prevent an excessive load from being applied to the second motor 47 and the second transmission mechanism 48 due to the failure of the magnetic sensor 81 and the failure to reach these.

  The rotation shaft 41 of the actuator 40 is a member that changes the light distribution by the lamp unit 20 mounted on the vehicle 2. Therefore, it is possible to avoid a situation where glare is given to the vehicle ahead based on inaccurate light distribution control or a situation where necessary illumination is insufficient.

  The above embodiment is for facilitating understanding of the present invention, and does not limit the present invention. The present invention can be modified and improved without departing from the spirit of the present invention, and it is obvious that the present invention includes equivalents thereof.

  In the above embodiment, the signal level corresponding to the magnetism generated by the south poles of the magnets 60, 70, and 80 is L1, and the signal level corresponding to the magnetism generated by the north pole is L2. However, the relationship between the magnetic pole and the signal level may be reversed.

  In the above embodiment, only when the output signal level of the magnetic sensors 61, 71, 81 transitions from L1 to L2 is used for determining the control reference position. However, only when the output signal level transitions from L2 to L1 may be used to determine the control reference position.

  The arrangement of the magnets 60, 70, 80 and the magnetic sensors 61, 71, 81 can be appropriately determined as long as a magnetic change accompanying the displacement of the controlled object can be detected. For example, a magnet may be provided on the rotary shade 37 or the rotation shaft 41 of the actuator 40, and the magnetic sensor may be disposed so as to face the magnet.

  In the above embodiment, the rotary shade 37 is configured to be able to form two types of so-called low beam patterns and high beam patterns. The number of light distribution patterns that can be formed by the rotary shade 37 may be three or more. Such a configuration can be obtained by appropriately changing the shape of the edge projected in front of the projection lens 31. As the number of light distribution patterns to be formed increases, it is necessary to provide edges having different shapes within a limited range of circumferential angles, and thus more accurate rotation control is required. Therefore, the effect of the control becomes more prominent as the number of light distribution patterns to be formed increases.

  As long as a plurality of light distribution patterns can be switched, a plate-shaped shade may be displaced by an actuator instead of the rotary shade 37. In this case, the control described with reference to the actuator 40 can be applied.

  The lamp unit 20 is not necessarily provided with a shade and need not be configured to be able to perform both swivel control and leveling control of the optical axis A1 of the projection lens 31. The configuration may be such that at least one of light distribution switching control by shade, swivel control of the optical axis A1, and leveling control can be executed. In the case of a lamp unit that does not include a shade, it is not necessarily required to be mounted on the headlamp device 10. The projection lens 31 can be mounted on an appropriate illumination device that needs to be controlled to change the direction of the optical axis A1.

  As shown in FIG. 1, the receiver 4 a that receives output signals from the magnetic sensors 61, 71, 81, the drive shaft 38 a of the motor 38, the drive shaft 43 a of the first motor 43, and the drive shaft 47 a of the second motor 47. As long as the output unit 4b that outputs a signal for rotating the output unit 4b is provided, it is not necessary for the integrated control unit 4 to have all the functions of the control device. It is good also as a structure which arrange | positions a control apparatus in the housing 11 with which the headlamp apparatus 10 is provided, and makes the said control apparatus bear at least one part of the function implement | achieved by the integrated control part 4. FIG.

  The above-described control does not necessarily need to be performed on the motor provided in the lamp mounted on the vehicle. For a system in which the control reference position is determined based on the magnetic change detected by the magnetic sensor and the rotational angle position of the drive shaft corresponding to the position where the magnetic change is detected can vary depending on the driving direction of the motor. Can be applied.

  1: motor control system, 2: vehicle, 4: integrated control unit, 4a: receiving unit, 4b: output unit, 20: lamp unit, 37: rotary shade, 38: motor, 38a: drive shaft, 39: transmission mechanism, 43: first motor, 43a drive shaft, 44: first transmission mechanism, 46: stopper, 47: second motor, 47a: drive shaft, 48: second transmission mechanism, 60: magnet, 61: magnetic sensor, 70: Magnet: 71: Magnetic sensor, 80: Magnet, 81: Magnetic sensor, L1: First output signal level, L2: Second output signal level, t1: Rotating drive shaft to detect transition from signal level L1 to L2 T4: When the transition from the signal level L1 to L2 is detected after the drive shaft is reversely rotated, θ1: The rotational angle position corresponding to the control reference position, Δθ: The rotational angle position where the signal level transition occurs difference

Claims (6)

A motor having a drive shaft;
A transmission mechanism connected to the drive shaft;
A movable member that moves according to the driving force of the motor transmitted by the transmission mechanism;
A magnet that is displaced together with the movable member;
A magnetic sensor for detecting magnetism generated by the magnet;
A controller for outputting a signal for rotating the drive shaft,
The magnetic sensor outputs a signal having a first level corresponding to the first state of the magnetism and a second level corresponding to the second state of the magnetism to the control device;
The control device determines a rotation angle position of the drive shaft when the drive shaft is rotated to detect a transition from the first level to the second level as a control reference position of the movable member,
When the control device rotates the drive shaft and detects a transition from the second level to the first level, the control device reversely rotates the drive shaft to change the first level to the second level. A motor control system that determines a rotation angle position of the drive shaft when detected as the control reference position. The control device detects the transition from the second level to the first level and then reversely rotates the drive shaft until the transition from the first level to the second level is detected. Estimating the amount of backlash of the transmission mechanism based on the amount of rotation of the drive shaft;
The motor control system according to claim 1, wherein the control device corrects a signal for rotating the drive shaft based on the estimated backlash amount.   3. The control device according to claim 1, wherein the control device determines that the magnetic sensor has failed when the transition from the first level to the second level cannot be detected even when the drive shaft is rotated by a predetermined amount. The motor control system described. A regulating member for regulating the movement of the movable member;
The motor control system according to claim 3, wherein the control device determines a rotation angle position of the drive shaft when the restriction by the restriction member is detected before rotating the drive shaft by the predetermined amount as the control reference position. .   The motor control system according to any one of claims 1 to 4, wherein the movable member is a member that changes light distribution by a lamp mounted on a vehicle. A motor control device having a drive shaft,
A receiver for receiving an output signal from the magnetic sensor;
An output unit for outputting a signal for rotating the drive shaft,
The output signal has a first level corresponding to a magnetic first state and a second level corresponding to the magnetic second state;
The rotation angle position of the drive shaft when the drive shaft is rotated to detect a transition from the first level to the second level is defined as a control reference position,
When the transition from the second level to the first level is detected by rotating the drive shaft, the transition from the first level to the second level is detected by reversely rotating the drive shaft. A control device that determines a rotation angle position of a drive shaft as the control reference position.

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