JP4333562B2 - Vehicle headlamp device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To quickly and precisely perform the initial setting of the head lamp in the predetermined initial direction. <P>SOLUTION: The head lamp device for a vehicle detects a steering angle for the vehicle, turns the head lamp according to the steering angle detection value based on a predetermined initial direction, and controls the irradiation direction. The head lamp device turns the head lamp at a first speed to abut to a stopper. When the head lamp device repeatedly detects the turning angle of the head lamp, and the turning angle detection value is no longer updated to a smaller value or larger value, the head lamp device abuts the head lamp to a stopper at a second speed slower than a first speed. When the lead lamp device repeatedly detects the turning angle of the head lamp, and the turning angle detection value is no longer updated to the smaller value or the larger value, the head lamp device determines that the head lamp is at the position of the stopper, and turns the head lamp by a predetermined angle from the position of the stopper to initially set to the predetermined direction. <P>COPYRIGHT: (C)2006,JPO&amp;NCIPI

Description

  The present invention relates to a vehicle headlamp device, and in particular, to improve a method for setting a reference direction (initial direction) when controlling the irradiation direction of a headlamp.

  There is a vehicle headlamp device (AFS: Adaptive Front-Lighting System) that changes the direction of headlamp illumination to the left and right according to the driving conditions of the vehicle, such as the steering angle, and ensures visibility in the direction of travel. It is known (see, for example, Patent Document 1).

Prior art documents related to the invention of this application include the following.
JP 2004-106770 A

  By the way, in the above-described vehicle headlamp device, it is necessary that the traveling direction of the vehicle by steering and the irradiation direction of the headlamp correspond to each other correctly. Therefore, when the ignition switch is turned on, A process of initializing the angle to a predetermined reference angle, for example, an angle in the straight direction of the vehicle is performed. By using a stepping motor as a drive source for rotating the headlamp, the rotation angle of the headlamp can be controlled with high accuracy. Therefore, if the reference angle can be detected accurately, the swivel angle of the headlamp can be set. It can be controlled with high accuracy.

  In the above-described conventional vehicle headlamp device, the swivel angle after turning the headlamp against the stoppers on the left and right ends and returning a predetermined angle from the position is a reference angle (control origin position) for swivel control, which will be described later. The initialization process is performed. However, if the initialization process takes a long time, it takes time to irradiate the direction in which the field of view is to be secured, and the convenience is impaired. Therefore, the initialization process must be completed in a short time. Therefore, it is conceivable to increase the rotation speed of the headlamp until it hits the stopper during the initialization process. However, the amount of bounce (bounce amount) after hitting the stopper increases and the correct stopper position can be set. As a result, it is impossible to correctly initialize the swivel control to the origin position.

  In a vehicle headlamp device that detects a steering angle of a vehicle, rotates a headlamp according to a steering angle detection value with reference to a predetermined initial direction, and controls an irradiation direction. The head is turned at a speed of the same and hits the stopper, and the turning angle of the headlamp is repeatedly detected. If the detected value of the turning angle is not updated to a smaller value or a larger value, the first speed slower than the first speed is obtained. The headlamp is abutted against the stopper at a speed of 2 and the rotation angle of the headlamp is repeatedly detected. When the detected rotation angle is not updated to a smaller value or a larger value, the headlamp is positioned at the stopper. The headlamp is rotated by a predetermined angle from the position of the stopper, and is initially set in a predetermined initial direction.

  According to the present invention, the headlamp can be quickly and accurately initialized in a predetermined initial direction.

  FIG. 1 shows the overall configuration of an embodiment, and FIG. 2 is a diagram showing a swivel lamp actuator of an embodiment. The ignition switch 1 is a switch that is turned on when an ignition key (not shown) is set to an ON position or a START position. When the ignition switch 1 is turned on, a headlamp (hereinafter referred to as a swivel lamp) that can change the irradiation direction in the lateral direction of the vehicle. Irradiation direction control (hereinafter referred to as swivel control), and swivel control of the swivel lamp is not performed when it is off. The steering angle sensor 2 detects the steering angle aSTR of the steering, and the vehicle speed sensor 3 detects the vehicle speed aVSP based on the rotational speed of the wheels. The headlight switch 4 is an operation switch for the driver to turn on the swivel lamp. When the driver is on, the headlight switch 4 performs the swivel control toward the swivel angle target value calculated based on the steering angle aSTR, the vehicle speed aVSP, and the like. Returns the irradiation direction of the swivel lamp to a predetermined initial direction (the straight direction of the vehicle in this embodiment).

  As shown in FIG. 2, the vehicle left swivel lamp actuator 5 includes a stepping motor 6, a gear mechanism 7, and a position sensor 8, and rotates the swivel lamp 9 on the vehicle left side to change the irradiation direction to the left and right direction of the vehicle. A gear mechanism 7 is engaged with the output shaft of the stepping motor 6, and the swivel lamp 9 is rotated by reducing the rotational speed of the motor 6. As shown in FIG. 3, when the stepping motor 6 is rotated in the clockwise direction (CW direction), the irradiation direction is changed toward the center of the vehicle. Conversely, when the stepping motor 6 is rotated in the counterclockwise direction (CCW direction), the irradiation is performed. The direction changes toward the outside of the vehicle.

  The position sensor 8 detects a swivel angle of the swivel lamp 9 after being decelerated and rotated by using a generally used hall sensor or the like. FIG. 4 shows the characteristics of the output voltage [V] with respect to the swivel angle [deg] of the position sensor 8. The stopper 10 interferes with a projection (not shown) provided on the gear mechanism 7 or the swivel lamp 9, and regulates the rotation angle of the swivel lamp 9 so that the swivel lamp 9 does not rotate beyond a predetermined angle range. To do.

  The vehicle right swivel lamp actuator 11 includes a stepping motor 12, a gear mechanism 13, and a position sensor 14, and rotates the swivel lamp 15 on the left side of the vehicle to change the irradiation direction to the left and right direction of the vehicle. A gear mechanism 13 is engaged with the output shaft of the stepping motor 12, and the swivel lamp 15 is rotated by reducing the rotational speed of the motor 12. As shown in FIG. 3, when the stepping motor 12 is rotated in the clockwise direction (CW direction), the irradiation direction is changed toward the center of the vehicle. Conversely, when the stepping motor 12 is rotated in the counterclockwise direction (CCW direction), the irradiation is performed. The direction changes toward the outside of the vehicle.

  The position sensor 14 uses a commonly used hall sensor or the like, and detects the swivel angle of the swivel lamp 15 after being decelerated and rotated. FIG. 4 shows the characteristics of the output voltage [V] with respect to the swivel angle [deg] of the position sensor 14. The stopper 16 interferes with a projection (not shown) provided on the gear mechanism 13 or the swivel lamp 15, and regulates the rotation angle of the swivel lamp 15 so that the swivel lamp 15 does not rotate beyond a predetermined angle range. To do.

  The swivel control ECU 100 includes a microcomputer and peripheral components such as a memory and an A / D converter, and an ignition switch 1, a steering angle sensor 2, a vehicle speed sensor 3, a headlight switch 4, a predetermined control cycle (for example, 10 msec), Signals from the position sensors 8 and 14 are read, and drive pulses for the stepping motors 6 and 12 are output. As shown in FIG. 1, the swivel control ECU 100 includes a state transition determination unit 110, a target step number calculation unit 120, and a drive pulse generation unit 130 configured in the form of a microcomputer software.

  The operation of the state transition determination unit 110 will be described with reference to the state transition diagram shown in FIG. In the following description, the swivel lamp 9 on the left side of the vehicle and the swivel lamp 15 on the right side of the vehicle operate in the same manner except for the direction of operation, and will be described together. When the ignition switch 1 is turned on, the state 1 is entered. In the state 1, the process shown in FIG. 6 is performed to detect the contact state of the swivel lamps 9 and 15 with the stoppers 10 and 16. First, the stepping motors 6 and 12 are driven at high speed in the direction of the stoppers 10 and 16, and the values of the position sensors 8 and 14 are monitored. In step 1, it is determined whether the values of the position sensors 8 and 14 are predetermined values, which is less than 1 deg or more than 1 deg in this embodiment. When the current value of the position sensors 8 and 14 is 1 deg or more, the process proceeds to step 2 and the “minimum value” of the position sensors 8 and 14 is set to 1 deg.

If the current value of the position sensors 8 and 14 is less than 1 deg, the process proceeds to step 3 to determine whether or not the current value of the position sensors 8 and 14 is smaller than the “minimum value”. If the current value is smaller than the “minimum value”, it is determined that the swivel lamps 9 and 15 have not yet hit the stoppers 10 and 16, and the process proceeds to step 4 to set the current values of the position sensors 8 and 14 to the “minimum value”. Set to "". On the other hand, if the current value is equal to or greater than the “minimum value”, the process proceeds to step 5 where the state transition number is set to 2 and the state transitions to state 2.
That is, in the state 1, when the swivel lamps 9 and 15 are rotated and abutted against the stoppers 10 and 16, the values of the position sensors 8 and 14 are less than a predetermined value (for example, 1 deg) and updated to a smaller value. If not, it is determined that the swivel lamps 8 and 14 have hit the stoppers 10 and 16, and the state transitions to state 2.

  In state 2, the processing shown in FIG. 7 is performed to determine the stopper position. First, the stepping motors 6 and 12 are driven in the direction of the stoppers 10 and 16, and the values of the position sensors 8 and 14 are monitored. At this time, the driving speed of the stepping motors 6 and 12 is set to a slow speed of, for example, 1/2 to 1/10 of the driving speed in the state 1. In step 5, it is determined whether or not the current values of the position sensors 8 and 14 are smaller than the “minimum value” set in the process shown in FIG. If the current values of the position sensors 8 and 14 are smaller than the “minimum value”, the process proceeds to step 6, the current value is set to “minimum value”, and then the counter value is set to 0 in step 7. This counter is for counting the number of times the “minimum value” is not updated.

When the current values of the position sensors 8 and 14 are “minimum value” or more in step 5, the process proceeds to step 8 to add 1 to the counter value. It is checked in step 9 whether the counter value has reached 10, that is, the number of times the position sensors 8 and 14 have not updated the “minimum value” has reached 10 times. , And the state transition number is set to 3, and transition is made to state 3.
That is, in the state 2, the swivel lamps 9 and 15 are rotated at a driving speed slower than the driving speed in the case of the state 1 and abut against the stoppers 10 and 16, and the values of the position sensors 8 and 14 are updated to a smaller value. When the number of times of stoppage reaches 10 times, it is determined that the swivel lamps 8 and 14 have completely hit the stoppers 10 and 16, and the state transitions to state 3.

  In the state 3, the swivel lamps 9 and 15 are driven by a predetermined angle toward the straight direction of the vehicle by the stepping motors 6 and 12 and driven by 1 deg in this embodiment, and this position is set as the origin position of the swivel control. The angle is defined as a reference angle (an angle in the straight direction). Note that the driving speed of the stepping motors 6 and 12 in the state 3 is the same as or faster than the driving speed in the state 1. Thereafter, the state transits to state 4. In the state 4, the swivel control of the swivel lamps 9 and 15 is performed based on the state of the steering angle aSTR, the vehicle speed aVSP, and the headlight switch 4 in order to secure the field of view in the traveling direction of the vehicle.

Next, the target step number calculation unit 120 of the swivel control ECU 100 shown in FIG. 1 will be described. The target step number calculation unit 120 calculates the target step number of the stepping motors 6 and 12 based on the state transition number from the state transition determination unit 110, the steering angle aSTR from the steering angle sensor 2, and the vehicle speed aVSP from the vehicle speed sensor 3. calculate. However, when the state transition number is other than 4, the target number of steps is not calculated. When the state transition number is 4, an optimum target swivel angle for the driver is obtained according to the steering angle aSTR and the vehicle speed aVSP. Next, based on the resolution of the stepping motors 6 and 12 and the gear ratio of the gear mechanisms 7 and 13, the target number of steps is obtained by the following equation.
Target step number = target swivel angle / (resolution / gear ratio)

  The drive pulse generation unit 130 of the swivel control ECU 100 will be described. The drive pulse generator 130 generates the drive pulse number of the stepping motors 6 and 12 based on the target step number of the target step number calculator 120. When the state transition number is 1, an output pulse is generated so that the stepping motor 6 rotates in the clockwise direction, and an output pulse is generated so that the stepping motor 12 rotates in the counterclockwise direction. The output pulse at this time is a high frequency, for example, 400 PPS, and the driving speed of the stepping motors 6 and 12 is increased.

  When the state transition number is 2, an output pulse is generated so that the stepping motor 6 rotates in the clockwise direction, and an output pulse is generated so that the stepping motor 12 rotates in the counterclockwise direction. The output pulse at this time is a low frequency, for example, 20 PPS, and the driving speed of the stepping motors 6 and 12 is lowered. When the state transition number is 3, an output pulse is generated so that the stepping motor 6 rotates counterclockwise, and an output pulse is generated so that the stepping motor 12 rotates clockwise. The output pulse at this time is a high frequency, for example, 400 PPS, and the driving speed of the stepping motors 6 and 12 is increased.

  When the state transition number is 4, the target step number is compared with the current actual step number, and an output pulse is generated as follows. For the stepping motor 6, when the target number of steps is larger than the current actual number of steps, an output pulse is generated so as to rotate counterclockwise, and conversely, when the target number of steps is smaller than the current actual number of steps, An output pulse is generated to rotate in the turning direction. For the stepping motor 12, an output pulse is generated so as to rotate in the clockwise direction when the target step number is larger than the current actual step number, and conversely when the target step number is smaller than the current actual step number. An output pulse is generated to rotate in the turning direction.

  8 to 10 are measured by changing the rotation speed of the stepping motors 6 and 12 when initializing the swivel angle of the swivel lamps 9 and 15 to the angle in the straight direction of the vehicle (control origin position in the figure). The result of initialization processing is shown. FIG. 8 shows the result when the stepping motors 6 and 12 are always driven at a high speed to perform the initialization process. In this case, the initialization process ends early, but the correct amount of the stoppers 10 and 16 cannot be detected because the amount of bounce from the stoppers 10 and 16 is large, and the swivel lamps 9 and 15 after initialization The swivel angle deviates from the reference angle, that is, the control origin position.

  FIG. 9 shows the result when the stepping motors 6 and 12 are always driven at a low speed and the initialization process is performed. In this case, since the bounce amount from the stoppers 10 and 16 is small, the correct positions of the stoppers 10 and 16 can be detected, and the swivel lamps 9 and 15 are accurately initialized to the reference angle of the swivel angle, that is, the control origin position. However, the time required for the initialization process becomes longer.

  FIG. 10 shows the initialization processing result according to the above-described embodiment. In one embodiment, first, the stepping motors 6 and 12 are driven at a high speed until they hit the stoppers 10 and 16 (the period indicated by (a) in the figure), and then the positions of the stoppers 10 and 16 are determined. In the meantime (period shown by (b) in the figure), the stepping motors 6 and 12 are driven at a slow speed, and until the swivel angle is initialized to the reference angle of the swivel angle, that is, the control origin position (in the figure ( Since the stepping motors 6 and 12 are driven at a high speed during the period indicated by c), the amount of bounce when abutting against the stoppers 10 and 16 is reduced and the correct positions of the stoppers 10 and 16 are detected. Accordingly, the swivel lamps 9 and 15 can be accurately initialized to the reference angle of the swivel angle, that is, the control origin position, while shortening the initialization process time.

  Thus, according to one embodiment, the vehicle steering angle is detected by detecting the steering angle of the vehicle, rotating the swivel lamp in accordance with the detected steering angle value based on the predetermined initial direction, and controlling the irradiation direction. In the lighting device, the swivel lamp is rotated at the first speed and abuts against the stopper, and the rotation angle of the swivel lamp is repeatedly detected, and the rotation angle detection value is not updated to a smaller value or a larger value. If the swivel lamp is abutted against the stopper at the second speed slower than the first speed and the swiveling angle of the swivel lamp is repeatedly detected, and the rotation angle detection value is not updated to a smaller value or a larger value. It is determined that the swivel lamp is at the stopper position, and the swivel lamp is rotated by a predetermined angle from the position of the stopper to be initialized in a predetermined initial direction. As a result, the amount of bounce when abutting against the stopper is reduced, so that the correct position of the stopper can be detected, and the swivel lamp can be accurately initialized in a predetermined initial direction while shortening the initialization process time. Can do.

  Further, according to the embodiment, the swivel lamp is abutted against the stopper at the second speed, and the rotation angle of the swivel lamp is repeatedly detected, and the rotation angle detection value is updated to a smaller value or a larger value. If the swivel lamp reaches the predetermined number of times, it is determined that the swivel lamp is at the stopper position, and the swivel lamp is rotated by a predetermined angle from the position of the stopper so that the initial setting is performed in the predetermined initial direction. The position can be detected more accurately, and the swivel lamp can be initialized more accurately in a predetermined initial direction.

  The correspondence between the constituent elements of the claims and the constituent elements of the embodiment is as follows. That is, the swivel lamps 9 and 15 are the headlamps, the swivel lamp actuators 5 and 11 are the headlamp rotation means, the position sensors 8 and 14 are the rotation angle detection means, and the swivel control ECU 100 is the irradiation direction initialization means. The steering angle sensor 2 constitutes a steering angle detection means. The above description is merely an example, and when interpreting the invention, the correspondence between the items described in the above embodiment and the items described in the claims is not limited or restricted.

  In one embodiment, the swivel lamp (rotation angle) detection value of the swivel lamp is not updated to a smaller value, and an example is shown in which it is determined that the swivel lamp hits the stopper, as shown in FIG. If a swivel angle detection sensor with special characteristics is used and the swivel angle (rotation angle) increases as the swivel lamp rotates in the stopper direction, the sensor output voltage increases. If the swivel angle (rotation angle) detection value is not updated to a larger value, it is determined that the swivel lamp is hitting the stopper.

  Further, in the embodiment, an example in which the predetermined initial irradiation direction of the swivel lamp is set as the straight traveling direction of the vehicle has been described. However, since the predetermined initial irradiation direction of the swivel lamp is a reference direction in swivel control, It is not limited to. However, when the initial irradiation direction is not the straight traveling direction of the vehicle, it is necessary to return the irradiation direction to the straight traveling direction of the vehicle instead of the initial irradiation direction when the ignition is off.

It is a figure which shows the structure of one embodiment. It is a figure which shows the structure of the swivel lamp actuator of one embodiment. It is a figure which shows the rotation direction of a stepping motor, and the irradiation direction of a swivel lamp. It is a figure which shows the characteristic of the position sensor which detects the swivel angle of a swivel lamp. It is a state transition diagram of swivel control. It is a flowchart which shows a process until a swivel lamp is made to abut against a stopper. It is a flowchart which shows the process until it fixes a stopper position. It is a figure which shows the result at the time of performing an initialization process by always driving a stepping motor at a high speed. It is a figure which shows the result at the time of performing an initialization process by always driving a stepping motor at a slow speed. It is a figure which shows the initialization process result of one Embodiment.

Explanation of symbols

1 ignition switch 2 steering angle sensor 3 vehicle speed sensor 4 headlight switch 5 left swivel lamp actuator 6 left stepping motor 7 left gear mechanism 8 left position sensor 9 left swivel lamp 10 left stopper 11 right swivel lamp actuator 12 right stepping motor 13 right side Gear mechanism 14 Right position sensor 15 Right swivel lamp 16 Right stopper 100 Swivel control ECU

Claims (3)

A headlamp rotating means for rotating the headlamp in the left-right direction of the vehicle to change the irradiation direction;
Rotation angle detection means for detecting the rotation angle of the headlamp;
Irradiation direction initialization means for rotating the headlamp by the headlamp rotation means to initialize the irradiation direction to a predetermined initial direction;
Steering angle detection means for detecting the steering angle of the vehicle;
A vehicle headlight provided with an irradiation direction control means for rotating the headlamp by the headlamp rotation means according to the steering angle detection value with reference to the predetermined initial direction and controlling the irradiation direction. A lighting device,
The irradiation direction initialization means rotates the headlamp at a first speed and abuts against the stopper, and repeatedly detects the rotation angle of the headlamp, and the rotation angle detection value is smaller or more If it is not updated to a larger value, the headlamp is abutted against the stopper at a second speed slower than the first speed, and the rotation angle of the headlamp is repeatedly detected. If it is not updated to a smaller value or a larger value, it is determined that the headlamp is at the position of the stopper, and the headlamp is rotated by a predetermined angle from the position of the stopper to be initialized in the predetermined initial direction. A vehicle headlamp apparatus characterized by the above. The vehicle headlamp device according to claim 1,
The irradiation direction initialization means abuts the headlamp against the stopper at the second speed and repeatedly detects the rotation angle of the headlamp, and the rotation angle detection value is a smaller value or a larger value. When the number of times of no longer being updated reaches the predetermined number of times, it is determined that the headlamp is at the position of the stopper, and the headlamp is rotated by a predetermined angle from the position of the stopper to be initially set in the predetermined initial direction. A vehicular headlamp device characterized in that: A method for initializing an irradiation direction of a vehicle headlamp device that detects a steering angle of a vehicle, rotates a headlamp according to a detected steering angle value based on a predetermined initial direction, and controls the irradiation direction. There,
The headlamp is rotated at the first speed and abutted against the stopper, and the rotation angle of the headlamp is repeatedly detected. When the detected rotation angle is not updated to a smaller value or a larger value, the first When the headlamp is abutted against the stopper at a second speed slower than the first speed and the rotation angle of the headlamp is repeatedly detected, and the rotation angle detection value is not updated to a smaller value or a larger value. A method for initializing an irradiation direction, characterized in that the headlamp is determined to be at a stopper position, and the headlamp is rotated by a predetermined angle from the position of the stopper to be initially set in a predetermined initial direction.

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