Control device, program, and vehicle lamp fitting

Abstract

A control device (60) receives a signal relating to the angle of the emission direction of light emitted from a lamp unit (30), and controls an actuator (50), which is capable of changing the orientation of the lamp unit (30), such that the torque of a motor (52) is transmitted to the lamp unit (30) and the emission direction of the light is inclined along a predetermined plane, wherein: the control device (60) performs first control for controlling the actuator (50) such that the angle of the emission direction approaches a first angle (SA1), different from a target angle (TA), from the opposite side to the target angle (TA) side, relative to the first angle (SA1), and then performs second control for controlling the actuator (50) such that the angle of the emission direction approaches the target angle (TA), on the basis of the signal relating to the angle of the emission direction after the first control has been performed.

Description

Control Device, Program, and Vehicle Lamp

[0001] The present invention relates to a control device, a program, and a vehicle lamp.

[0002] A vehicle lamp whose orientation of a lamp unit can be changed by an actuator is known. Patent Document 1 below discloses such a vehicle headlamp.

[0003] The vehicle headlamp of Patent Document 1 below includes a lamp unit, an actuator, and a control device that controls the actuator. The actuator can change the orientation of the lamp unit such that the light emission direction of the lamp unit is tilted in the vertical direction by the torque of a motor. The control device controls the actuator based on the detection value of an inclination detection device capable of detecting the inclination angle of the vehicle. Therefore, according to this vehicle headlamp, the inclination in the vertical direction of the light emission direction of the lamp unit can be changed according to the inclination of the vehicle.

[0004] Japanese Patent No. 5947947

[0005] In a vehicle headlamp, generally, when it is attached to a vehicle or the like, adjustment of the light emission direction with respect to the vehicle is performed. Such adjustment of the light emission direction is performed, for example, by controlling an actuator based on the measurement result of a measurement device that measures the light emission direction emitted from the lamp unit. Members constituting the motor tend to rattle. Also, rattling tends to occur between torque transmission members that transmit the torque of the motor, such as gears, of the actuator. Therefore, due to the influence of such rattling, even when the actuator is controlled based on the measured light emission direction, the angle of the light emission direction may deviate from the target angle. There is a demand to reduce such a deviation and improve the accuracy of adjusting the light emission direction emitted from the lamp unit.

[0006] Therefore, an object of the present invention is to provide a control device, a program, and a vehicle lamp that can improve the accuracy of adjusting the light emission direction emitted from the lamp unit.

[0007] To achieve the above objective, the present invention provides a control device that receives a signal relating to the angle of the emission direction of light emitted from a lighting unit and transmits the torque of a motor to the lighting unit to control an actuator capable of changing the orientation of the lighting unit so that the emission direction is tilted along a predetermined plane, wherein the control device performs a first control to control the actuator so that the angle of the emission direction approaches a first angle different from a target angle, using the first angle as a reference, from the opposite side from the target angle, and then performs a second control to control the actuator so that the angle of the emission direction approaches the target angle based on the signal relating to the angle of the emission direction after the first control.

[0008] The present invention also relates to a program executed on a control device that receives a signal relating to the angle of the emission direction of light emitted from a lighting unit and transmits the torque of a motor to the lighting unit to change the orientation of the lighting unit so that the emission direction is tilted along a predetermined plane, characterized in that the control device is made to perform a first control, which involves controlling the actuator to bring the angle of the emission direction closer to a first angle different from a target angle, using the first angle as a reference, from the opposite side from the target angle side; and a second control, which involves controlling the actuator to bring the angle of the emission direction closer to the target angle based on the signal relating to the angle of the emission direction after the first control has been performed.

[0009] Furthermore, the vehicle lighting device of the present invention comprises a lighting unit, an actuator capable of changing the orientation of the lighting unit by transmitting the torque of a motor to the lighting unit so that the direction of light emission is tilted along a predetermined plane, and a control device that receives a signal relating to the angle of the emission direction and controls the actuator, wherein the control device performs a first control to control the actuator so that the angle of the emission direction approaches a first angle different from the target angle, using the first angle as a reference, from the opposite side from the target angle, and then performs a second control to control the actuator so that the angle of the emission direction approaches the target angle based on the signal relating to the angle of the emission direction after the first control.

[0010] In the control device, program, and vehicle lighting device described above, the direction in which the angle of the emission direction changes is the same in the first control and the second control performed after the first control. Therefore, rattle between parts can be eliminated by the first control, and the angle of the emission direction can be accurately changed in the second control by making it less susceptible to the effects of such rattle. Accordingly, the control device, program, and vehicle lighting device described above can improve the accuracy of adjusting the emission direction when bringing the angle of the emission direction closer to the target angle.

[0011] The first angle may be set in advance, with reference to the target angle, in the direction in which the torque generated in the lighting unit by its own weight would change the angle before the first control was performed.

[0012] In the above configuration, when the angle of the emission direction approaches the first angle, and when the angle of the emission direction approaches the target angle, the direction of the torque transmitted from the motor to the luminaire unit is opposite to the direction of the torque due to the weight of the luminaire unit itself. Therefore, with the above configuration, rattling due to the weight of the luminaire unit after the first control can be suppressed, and the accuracy of adjusting the direction of light emission can be further improved.

[0013] The control device described above may set a first angle between the angle of the ejection direction before performing the first control and the target angle. Alternatively, the program described above may cause the control device to perform the step of setting a first angle between the angle of the ejection direction before performing the first control and the target angle.

[0014] According to the above configuration, when the angle of the firing direction is on the target angle side relative to the first angle, it becomes unnecessary to change the angle of the firing direction to the opposite side of the target angle relative to the first angle, thereby shortening the time required to adjust the firing direction.

[0015] The absolute value of the difference between the first angle and the target angle may be greater than or equal to a threshold value which is the absolute value of the change in the angle of the emission direction when a predetermined voltage is applied to the motor for a period longer than the motor's time constant.

[0016] If the period for which voltage is applied to the motor is shorter than the period of the motor's time constant, the accuracy of the change in the angle of the ejection direction tends to decrease. With the above configuration, the period for which voltage is applied to the motor in the second control becomes longer than the period of the motor's time constant. Therefore, with the above configuration, the accuracy of adjusting the angle of the ejection direction can be ensured.

[0017] In the above-described vehicle lighting fixture, the predetermined surface may be approximately parallel to the vertical surface.

[0018] As described above, the present invention provides a control device, a program, and a vehicle lighting device that can improve the accuracy of adjusting the direction of light emission from a lighting unit.

[0019] Figure 1 is a schematic diagram showing an adjustment system for adjusting the direction of light emission from a vehicle lamp according to an embodiment of the present invention. Figure 2 is a schematic diagram showing a vehicle headlight according to an embodiment. Figure 3 is a diagram showing the light distribution pattern of the low beam in the embodiment. Figure 4 is a flowchart showing an example of the operation of the control device in the calibration of the vehicle headlight. Figure 5 is a diagram for explaining the target angle and target range in the embodiment. Figure 6 is a diagram showing an example of the change over time of the angle of the light emission direction in calibration. Figure 7 is a diagram showing another example of the change over time of the angle of the light emission direction in calibration, similar to Figure 6.

[0020] Preferred embodiments of the control device, program, and vehicle lighting device according to the present invention will be described in detail below with reference to the drawings. The embodiments illustrated below are provided to facilitate understanding of the present invention and are not intended to limit its interpretation. For this reason, the present invention can be modified and improved from the following embodiments within the scope of the claims. In the drawings referenced below, the dimensions of each component may be shown differently for the sake of clarity. Also, in the drawings, for the sake of readability, reference numerals may be assigned to only some of the similar components, and some reference numerals may be omitted.

[0021] Figure 1 is a schematic diagram showing an adjustment system for adjusting the direction of light emitted from a vehicle lamp according to an embodiment of the present invention. As shown in Figure 1, the adjustment system SY of this embodiment includes a vehicle 100 equipped with a vehicle headlight 1 as a vehicle lamp, and a measuring device 110 for measuring the direction of light emitted from the vehicle headlight 1. In Figure 1, the X-axis direction indicates the front of the vehicle 100, the Z-axis direction indicates upward, and the Y-axis direction, which is perpendicular to the plane of the paper and moves towards the back, indicates the right direction of the vehicle 100. In this embodiment, the vehicle 100 is placed on a generally horizontal floor FL, and the measuring device 110 is placed on the floor FL in front of the vehicle 100 so as to be directly facing the vehicle headlight 1 at a predetermined distance. Generally horizontal includes, for example, a state that is horizontal, as well as a state that is tilted relative to the horizontal to such an extent that the influence on the calibration of the vehicle headlight 1, which will be described later, can be ignored. This state that is tilted relative to the horizontal includes, for example, a state that is tilted at a predetermined angle relative to the horizontal, which will be described later.

[0022] First, the vehicle headlight 1 will be described. The vehicle headlight 1 according to this embodiment mainly comprises a lamp unit 10, a control device 60, a memory 70, a first power supply circuit 81, and a second power supply circuit 82.

[0023] Figure 2 is a schematic diagram showing a vehicle headlight 1 according to this embodiment. As shown in Figure 2, the lamp unit 10 of this embodiment mainly comprises a housing 20, a lamp unit 30, a support member 40, and an actuator 50.

[0024] The housing 20 has a lamp housing 21 and a front cover 22. The front of the lamp housing 21 is open, and the front cover 22 is fixed to the lamp housing 21 so as to close the opening. The space formed by the lamp housing 21 and the front cover 22 is a housing space, and the luminaire unit 30, support member 40, and actuator 50 are housed in this housing space. The front cover 22 transmits light emitted from the luminaire unit 30.

[0025] The lighting unit 30 of this embodiment mainly comprises a main body 31 equipped with a light source (not shown), an upper connection part 32, and a lower connection part 35. Note that the internal structure of the main body 31 is omitted in Figure 2.

[0026] In this embodiment, the main body 31 emits light from a light source forward so that it forms a low beam pattern. The low beam emitted from the main body 31 is irradiated in front of the vehicle 100 via the front cover 22. The main body 31 may be equipped with a reflector, projection lens, etc., so that the light from the light source forms a low beam pattern, and the light source can be, for example, an LED (Light Emitting Diode). Furthermore, the light emitted from the main body 31 is not limited and may be, for example, a high beam, and the main body 31 may be able to change the light distribution pattern of the emitted light.

[0027] The upper connecting portion 32 of this embodiment includes a base portion 33 extending upward from the main body portion 31 and a connecting portion 34 fixed to the rear side of the base portion 33, with the connecting portion 34 connected to the support member 40. The support member 40 of this embodiment is a rod-shaped member extending in the front-rear direction and has a generally spherical pivot portion 41 at its front end. The rear end of the support member 40 is fixed to the lamp housing 21. The connecting portion 34 is provided with a recess into which the pivot portion 41 fits, and the upper connecting portion 32 is connected to the support member 40 when the pivot portion 41 fits into the recess. The luminaire unit 30, with the upper connecting portion 32 connected to the support member 40 in this way, can swing up and down and left and right within a predetermined range with respect to the support member 40, using the pivot portion 41 as a fulcrum.

[0028] In this embodiment, the lower connection portion 35 includes a base portion 36 extending downward from the main body portion 31 and a connection portion 37 fixed to the rear side of the base portion 36, to which the shaft 53 of the actuator 50, which will be described later, is connected. The lighting unit 30 is then supported by the support member 40 and the shaft 53.

[0029] The actuator 50 of this embodiment mainly comprises a case 51, a motor 52, and a shaft 53.

[0030] In this embodiment, the case 51 is a box-shaped member having an internal storage space and is fixed to the lamp housing 21. The motor 52 is a DC motor and is housed in the storage space of the case 51. The type of motor 52 is not limited.

[0031] The shaft 53 in this embodiment is a rod-shaped member extending in the front-rear direction. The shaft 53 has a generally spherical pivot portion 54 at its front end and a rack 55 behind the pivot portion 54. A hole is formed in the front of the case 51 through which the shaft 53 is inserted. The portion of the shaft 53 including the pivot portion 54 is located in front of the case 51, and the portion of the shaft 53 including the rack 55 is located in the housing space of the case 51. The shaft 53 is supported by a support mechanism (not shown) so as to be movable along the front-rear direction, which is the direction in which the shaft 53 extends.

[0032] The lower connection portion 35 has a connection portion 37 into which the pivot portion 54 fits. When the pivot portion 54 fits into this recess, the lower connection portion 35 is connected to the shaft 53. The lighting unit 30, with the lower connection portion 35 connected to the shaft 53 in this way, can swing up and down and left and right within a predetermined range with respect to the shaft 53, using the pivot portion 54 as a fulcrum.

[0033] The rack 55 is a gear provided on the outer circumferential surface of the shaft 53 along the longitudinal direction of the shaft 53, and meshes with a pinion gear 56 fixed to the output shaft 52a of the motor 52. When the pinion gear 56 rotates due to the torque of the motor 52, the shaft 53 moves in the forward and backward direction, and when the rotation direction of the motor 52 reverses, the direction of movement of the shaft 53 also reverses.

[0034] Although a diagrammatic explanation is omitted, as the shaft 53 moves forward, the torque of the motor 52 is transmitted to the lighting unit 30, causing the lighting unit 30 to tilt upward using the pivot portion 41 of the support member 40 as a fulcrum. As a result, the direction of light emission from the main body 31 of the lighting unit 30 is changed to be more upward than before the movement. Also, as the shaft 53 moves backward, the torque of the motor 52 is transmitted to the lighting unit 30, causing the lighting unit 30 to tilt downward using the pivot portion 41 as a fulcrum, and the direction of light emission from the main body 31 is changed to be more downward than before the movement.

[0035] In other words, the pinion gear 56 and shaft 53 are torque transmission members that transmit the torque of the motor 52 to the lighting unit 30, and the actuator 50 transmits the torque of the motor 52 to the lighting unit 30, and can change the orientation of the lighting unit 30 so that the direction of light emission is tilted along a plane that is generally parallel to a vertical plane that extends in the front-rear direction. This vertical plane is parallel to the X-axis and Z-axis directions and perpendicular to the Y-axis direction. Note that "generally parallel to the vertical plane" includes, for example, a state in which it is parallel to the vertical plane, as well as a state in which it is tilted with respect to the vertical plane to such an extent that the influence in the calibration of the vehicle headlight 1, which will be described later, can be ignored. This state inclined with respect to the vertical plane includes, for example, a state inclined at a predetermined angle with respect to the vertical plane, which will be described later.

[0036] Furthermore, the center of gravity 30G of the luminaire unit 30 in this embodiment is located in front of the pivot portion 41 and pivot portion 54, and the weight of the luminaire unit 30 generates a torque in the luminaire unit 30 that causes the direction of light emission to change downward.

[0037] The control device 60 consists of, for example, an integrated circuit such as a microcontroller, IC (Integrated Circuit), LSI (Large-scale Integrated Circuit), or ASIC (Application Specific Integrated Circuit), or an NC (Numerical Control) device. The control device 60 may or may not use a machine learning machine. The control device 60 is electrically connected to the memory 70, the first power supply circuit 81, the second power supply circuit 82, and the transmitting / receiving unit 120 provided in the vehicle 100, which will be described later.

[0038] The memory 70 is configured to store information and to be readable. The memory 70 is, for example, a non-transitory recording medium, and semiconductor recording media such as RAM (Random Access Memory) or ROM (Read Only Memory) are preferred, but any type of recording medium such as optical recording media or magnetic recording media may be included. Note that a "non-transitory" recording medium includes all computer-readable recording media except transient propagation signals, and does not exclude volatile recording media. The memory 70 and the control device 60 may be provided in an integrated package. The memory 70 stores programs for controlling the lighting unit 30 and the actuator 50, as well as information necessary for such control. The control device 60 reads the programs and information stored in the memory 70. The memory 70 also stores information based on instructions from the control device 60.

[0039] In this embodiment, the control device 60 reads a program for controlling the lighting unit 30 from the memory 70, outputs a signal to the first power supply circuit 81 to control the first power supply circuit 81, and thereby controls the lighting unit 30.

[0040] The first power supply circuit 81 includes a driver, and when a control signal is input from the control device 60, this driver adjusts the power supplied from a power supply (not shown) to the light source of the main body 31 of the luminaire unit 30. When power is supplied to the light source, light is emitted from the light source, and a low beam is emitted from the luminaire unit 30.

[0041] Furthermore, the control device 60 of this embodiment controls the actuator 50 by reading a program for controlling the actuator 50 from the memory 70 and outputting a signal to the second power supply circuit 82 to control the second power supply circuit 82.

[0042] The second power supply circuit 82 includes a driver. When a control signal is input from the control device 60, this driver adjusts the voltage applied to the motor 52 of the actuator 50 from a power supply (not shown), and the output shaft 52a of the motor 52 rotates according to the applied voltage. As a result, the shaft 53 moves in the front-back direction, and the torque of the motor 52 is transmitted to the lighting unit 30, changing the orientation of the lighting unit 30 so that the direction of light emission is tilted in the up-down direction.

[0043] Furthermore, the control device 60 in this embodiment outputs a control signal to the transmitting / receiving unit 120 provided in the vehicle 100, instructing the measuring device 110 to perform the measurement.

[0044] In this embodiment, the control device 60, the memory 70, the first power supply circuit 81, and the second power supply circuit 82 are arranged outside the housing 20. However, at least one of these may be housed in the accommodation space of the housing 20, and the second power supply circuit 82 may be housed in the accommodation space of the case 51 of the actuator 50. Further, the control device 60 may include at least one of the first power supply circuit 81 and the second power supply circuit 82, and may be included in a vehicle control device that controls an engine or the like of the vehicle 100. Further, the first power supply circuit 81 and the second power supply circuit 82 may be provided in an integrated package. Further, the control device 60, the first power supply circuit 81, and the second power supply circuit 82 may be provided in an integrated package. Further, at least one of the first power supply circuit 81 and the second power supply circuit 82 and the memory 70 may be provided in an integrated package, and the control device 60, the memory 70, the first power supply circuit 81, and the second power supply circuit 82 may be provided in an integrated package.

[0045] The transmission / reception unit 120 provided in the vehicle 100 is configured to transmit signals to the outside and receive signals from the outside. Examples of the transmission / reception unit 120 include an antenna. In this embodiment, the transmission / reception unit 120 transmits a signal input from the control device 60 to an external device as an electromagnetic wave, and receives a signal transmitted from the external device as an electromagnetic wave and outputs it to the control device 60.

[0046] Next, returning to FIG. 1, the measuring device 110 will be described. The measuring device 110 according to this embodiment mainly includes a control device 111, a memory 112, a light receiving unit 113, a calculation unit 114, and a transmission / reception unit 115.

[0047] The control device 111 has, for example, the same configuration as the control device 60, and controls some configurations provided in the measuring device 110. The memory 112, the light receiving unit 113, the calculation unit 114, and the transmission / reception unit 115 are electrically connected to the control device 111.

[0048] The memory 112 has, for example, the same configuration as the memory 70. Programs for controlling some components included in the measuring device 110 and information necessary for the control are stored in the memory 112. The control device 111 reads out the programs and information stored in the memory 112. Further, the memory 112 stores information according to an instruction from the control device 111.

[0049] The light receiving unit 113 of the present embodiment has a light receiving surface 113s that receives light, and generates information of an image showing an image of the light irradiated on the light receiving surface 113s. The generated image information is output to the calculation unit 114 via the control device 111. As a configuration of the light receiving unit 113, for example, a configuration in which semiconductor light receiving elements are arranged in a matrix can be mentioned. The measuring device 110 is disposed on the floor FL such that the light receiving surface 113s faces the vehicle headlamp 1 at a predetermined interval. When a low beam is emitted from the vehicle headlamp 1, the low beam is irradiated on the light receiving surface 113s, and image information showing the light distribution pattern of the low beam, which is an image of the low beam, is output to the calculation unit 114 via the control device 111.

[0050] FIG. 3 is a diagram showing the light distribution pattern of the low beam in the present embodiment, and is a diagram showing the light distribution pattern of the low beam formed on the light receiving surface 113s when the light receiving surface 113s is irradiated with the low beam. The light distribution pattern PL of the low beam of the present embodiment is for countries and regions where vehicles drive on the left side, and the cut-off line CL, which is the upper edge of the light distribution pattern PL of the low beam, includes a first line CL1, a second line CL2, and a third line CL3. The first line CL1 extends substantially horizontally, the second line CL2 extends leftward and upward from the left end of the first line CL1, and the third line CL3 extends substantially horizontally to the left from the left end of the second line CL2. The connection portion between the first line CL1 and the second line CL2 is the elbow point EP, and a hot zone (not shown), which is a region where the light intensity is the highest, is located near the elbow point EP.

[0051] The calculation unit 114 in this embodiment has the same configuration as, for example, the control device 60. The calculation unit 114 calculates the direction of low beam emission to the vehicle 100 from the information of the input image and the information previously stored in the memory 112. Examples of information stored in the memory 112 include the distance between the vehicle 100 and the measuring device 110, and the height from the floor FL to the vehicle headlight 1. In this embodiment, the calculation unit 114 extracts the position representing the elbow point EP in the above image and calculates the angle of the low beam emission direction in the vertical direction from that position. The calculated angle information is output to the transmitting / receiving unit 115 via the control device 111. In this embodiment, the angle of the emission direction is defined as zero degrees for the direction parallel to the horizontal direction, a positive angle for the angle between the direction upward from the horizontal direction and the horizontal direction, and a negative angle for the angle between the direction downward from the horizontal direction and the horizontal direction. In this embodiment, the low beam emission direction is toward the elbow point EP from the luminaire unit 30. The angle of the emission direction is the inclination angle of the emission direction with respect to the reference direction, and in this embodiment, it is the inclination angle of the emission direction with respect to the horizontal direction. The emission direction is inclined along a plane VP that is roughly parallel to the vertical plane extending in the front-rear direction and passes through the elbow point EP, as the orientation of the luminaire unit 30 is changed by the actuator 50.

[0052] The direction of emission of the low beam does not need to be any direction from the luminaire unit 30 toward a predetermined position in the low beam light distribution pattern PL. For example, it may be any direction from the luminaire unit 30 toward the hot zone in the low beam light distribution pattern. The calculation unit 114 only needs to be able to detect the direction of emission of the light emitted from the luminaire unit 30. The direction of emission of the light is any direction toward a predetermined position in the light distribution pattern of the light, and the predetermined position is not limited. Furthermore, there are no limitations on the method of detecting such emission direction. For example, the calculation unit 114 may extract a position representing the hot zone in the low beam light distribution pattern in the above image and calculate the angle of the low beam emission direction in the vertical direction from that position. Also, if the light emitted from the luminaire unit 30 is a high beam, for example, the calculation unit 114 may extract a position representing the hot zone in the high beam light distribution pattern and calculate the angle of the high beam emission direction in the vertical direction from that position. In addition, the control device 111 may also function as the calculation unit 114.

[0053] The transmitting / receiving unit 115 has a configuration similar to that of the transmitting / receiving unit 120 provided in, for example, a vehicle 100. In this embodiment, when the transmitting / receiving unit 115 receives a control signal transmitted from the transmitting / receiving unit 120, it sends the control signal to the control device 111. Also, when the transmitting / receiving unit 115 receives information on the angle of the emission direction calculated by the calculation unit 114 from the control device 111, it transmits a signal related to that angle to the outside. The transmitting / receiving unit 120 receives the signal related to the angle transmitted from the transmitting / receiving unit 115 and sends the signal to the control device 60. In this way, the control signal output from the control device 60 is input to the control device 111, and the signal related to the emission direction of the low beam emitted from the lighting unit 30 is input to the control device 60.

[0054] Next, we will explain the calibration of the vehicle headlight 1.

[0055] Figure 4 is a flowchart showing an example of the operation of the control device 60 in the calibration of the vehicle headlight 1. The program that executes the operations of this flowchart is stored in the memory 70. Therefore, the control device 60 executes the flowchart in Figure 4 by reading the program from the memory 70. As shown in Figure 4, the operation of the control device 60 in this embodiment comprises steps S1 to S7. In the initial state of Figure 4, as shown in Figure 1, the vehicle 100 is placed on the floor FL, and the measuring device 110 is placed on the floor FL in front of the vehicle 100 so as to face the vehicle headlight 1 at a predetermined distance.

[0056] <Step S1> This step involves acquiring information about the angle of the emission direction of light emitted from the lighting unit 30 in the vertical direction. In this step, first, the control device 60 controls the actuator 50 to change the angle of the emission direction of the emitted light upward by a predetermined angle. Specifically, the control device 60 outputs a control signal to the second power supply circuit 82 to control the second power supply circuit 82, thereby changing the angle of the emission direction upward by a predetermined angle. It is preferable that the direction in which the angle of the emission direction is changed is in accordance with the first angle, which will be described later, and is preferably in the direction from the first angle toward the target angle, which will be described later. It is also possible that such control of the actuator 50 is not required.

[0057] Next, the control device 60 controls the lighting unit 30 to emit a low beam from it. Specifically, the control device 60 outputs a control signal to the first power supply circuit 81 to control the first power supply circuit 81, thereby emitting a low beam from the lighting unit 30.

[0058] Next, the control device 60 outputs a control signal to the transmitting / receiving unit 120 instructing the measuring device 110 to perform the measurement, causing the transmitting / receiving unit 120 to transmit the control signal. The control signal is received by the transmitting / receiving unit 115 of the measuring device 110 and sent to the control device 111. The control device 111 measures the direction of light emission from the lighting unit 30 in response to the input of the control signal. Specifically, the control device 111 causes the light receiving unit 113 to generate image information showing the image of the light irradiated onto the light receiving surface 113s, and outputs this image information to the control device 111. Next, the control device 111 outputs this information to the calculation unit 114. The calculation unit 114 extracts the position representing the elbow point EP in the above image, calculates the angle of the low beam emission direction in the vertical direction from that position, and outputs the calculated angle information to the control device 111. The control device 111 outputs the angle information to the transmitting / receiving unit 115, and the transmitting / receiving unit 115 outputs a signal related to the angle. The signal is received by the transmitting / receiving unit 120 and sent to the control device 60. In this way, the control device 60 acquires information on the angle of the direction of emission of light emitted from the lighting unit 30 and stores this information in the memory 70, although it is not necessary to store this information in the memory 70. After this step, the control device 60 proceeds to step S2.

[0059] <Step S2> This step is a step in which the next step is determined based on the information of the angle of the light emission direction obtained in step S1. In this step, if the angle is outside the target range, the control device 60 proceeds to step S3. If the angle is within the target range, the control device 60 stops the emission of the low beam from the luminaire unit 30 and terminates the control in calibration. Figure 5 is a diagram for explaining the target angle and target range in this embodiment. As shown in Figure 5, the target range TR in this embodiment is a range that is greater than or equal to the angle obtained by subtracting a predetermined angle from the target angle TA, and less than or equal to the angle obtained by adding the predetermined angle to the target angle TA. In this embodiment, the target angle TA is zero degrees, and the predetermined angle is 0.05 degrees. The target angle TA is the target angle when adjusting the angle of the light emission direction, and the target range is the target range when adjusting the angle of the light emission direction; these are set in advance. The target angle TA and the predetermined angle are not limited.

[0060] <Step S3> This step is a step in which the next step is determined based on the information of the angle of the light emission direction obtained in step S1. In this step, if the angle of the emission direction is on the opposite side of the target angle TA, which is based on a first angle that is different from the target angle TA, the control device 60 proceeds to step S5. If the angle of the emission direction is the same as the first angle or on the target angle TA side, which is based on the first angle, the control device 60 proceeds to step S4.

[0061] As shown in Figure 5, in this embodiment, the first angle SA1 is predetermined and is a downward angle relative to the target angle TA, and is -1.0 degrees, but is not limited to this value. As mentioned above, the weight of the luminaire unit 30 generates a torque in the luminaire unit 30 that causes the direction of light emission to change downward. For this reason, the first angle SA1 in this embodiment is set relative to the target angle TA, on the side where the torque generated in the luminaire unit 30 by its own weight would change the angle of light emission. In addition, in this embodiment, the absolute value of the difference between the first angle SA1 and the target angle TA is greater than or equal to the threshold TH. The threshold TH is the absolute value of the change in the angle of emission direction when a predetermined voltage is applied to the motor 52 for a period longer than the time constant of the motor 52. In this embodiment, the time constant of the motor 52 is approximately 250 ms. The predetermined voltage is, for example, 12V to 16V, and the predetermined voltage in this embodiment is 13.5V. Furthermore, the threshold TH in this embodiment is 10 times or more the predetermined angle mentioned above, and is 0.5 degrees. Preferably, the threshold TH is 20 times or less the predetermined angle. Also, the time constant, predetermined voltage, and threshold TH are not limited.

[0062] <Step S4> This step is a pre-control step in which the actuator 50 is controlled so that the angle of the ejection direction becomes the second angle SA2, which is on the opposite side of the target angle TA, with respect to the first angle SA1. As shown in Figure 5, in this embodiment, the second angle SA2 is an angle below the first angle SA1. Also, the absolute value of the difference between the second angle SA2 and the first angle SA1 is greater than or equal to the threshold TH, and the second angle SA2 is -1.5 degrees, but is not limited to that. In this step, the control device 60 performs the above pre-control by outputting a control signal to the second power supply circuit 82 and controlling the second power supply circuit 82. In this embodiment, the above predetermined voltage is applied to the motor 52 during pre-control, but the applied voltage does not have to be constant.

[0063] <Step S5> This step is a first control step in which the actuator 50 is controlled to bring the angle of the light emission direction closer to a first angle SA1, which is different from the target angle TA, with the first angle SA1 as a reference, from the opposite side from the target angle TA. In this step, the control device 60 performs the first control by outputting a control signal to the second power supply circuit 82 and controlling the second power supply circuit 82. In this embodiment, in the first control, the above predetermined voltage is applied to the motor 52, but the applied voltage does not have to be constant.

[0064] Figure 6 shows an example of the change over time of the angle of the light emission direction during calibration. In Figure 6, the vertical axis represents angle and the horizontal axis represents time. In the example shown in Figure 6, the angle of the emission direction acquired in step S1 is an angle on the target angle TA side of the first angle SA1. Therefore, after step S3, the process proceeds to step S5 via step S4. As a result, the angle of the emission direction changes downward to approach the second angle SA2, and then changes upward to approach the first angle SA1.

[0065] Figure 7 is a diagram similar to Figure 6, showing another example of the change over time in the angle of the light emission direction during calibration. In the example shown in Figure 7, the angle of the emission direction acquired in step S1 is on the opposite side of the target angle TA from the first angle SA1. Therefore, the process proceeds to step S5 after step S3. As a result, the angle of the emission direction changes upward and approaches the first angle SA1.

[0066] <Step S6> This step is to acquire information about the angle of the direction of emission of light emitted from the lighting unit 30 after the first control. The procedure for acquiring information about the angle of the direction of emission of light is the same as in step S1, so the explanation of this procedure will be omitted. After this step, the control device 60 proceeds to step S7.

[0067] <Step S7> This step is a second control step in which the actuator 50 is controlled to bring the angle of the light emission direction closer to the target angle TA, based on the information of the angle of the light emission direction acquired in step S6. In other words, the second control is performed based on the signal relating to the angle of the light emission direction after the first control has been performed. In this step, the control device 60 performs the above second control by outputting a control signal to the second power supply circuit 82 and controlling the second power supply circuit 82. In this embodiment, the above predetermined voltage is applied to the motor 52 in the second control, but the applied voltage does not have to be constant.

[0068] In this way, in the calibration of the vehicle headlight 1 of this embodiment, the acquisition of information on the angle of the direction of light emission, and the first and second controls are repeated until the angle of the light emitted from the lamp unit 30 falls within the target range TR.

[0069] As described above, one aspect of the present invention according to this embodiment is a control device 60 that receives a signal relating to the angle of the direction of emission of light emitted from the light fixture unit 30, transmits torque from a motor 52 to the light fixture unit 30, and controls an actuator 50 capable of changing the orientation of the light fixture unit 30 so that the direction of emission is tilted along a plane VP that is generally parallel to the vertical plane. This control device 60 performs a first control to control the actuator so that the angle of the direction of emission of light approaches a first angle SA1, which is different from the target angle TA, with respect to the first angle SA1 as a reference, from the opposite side from the target angle TA. Furthermore, the control device 60 performs a second control to control the actuator 50 so that the angle of the direction of emission of light approaches the target angle TA, based on the signal relating to the angle of the direction of emission of light after the first control has been performed.

[0070] Another aspect of the present invention according to the above embodiment is a program executed by a control device 60 that receives a signal relating to the angle of the direction of emission of light emitted from the light fixture unit 30 and transmits torque from a motor 52 to the light fixture unit 30 to change the orientation of the light fixture unit 30 so that the direction of emission is tilted along a plane VP that is generally parallel to the vertical plane. This program causes the control device 60 to perform a first control, which involves controlling the actuator 50 to bring the angle of the direction of emission of light closer to a first angle SA1, which is different from the target angle TA, using the first angle SA1 as a reference, from the opposite side from the target angle TA. This program also causes the control device 60 to perform a second control, which involves controlling the actuator 50 to bring the angle of the direction of emission of light closer to the target angle TA, based on the signal relating to the angle of the direction of emission of light after the first control has been performed.

[0071] Furthermore, yet another embodiment of the present invention according to the above embodiment is a vehicle headlight 1 comprising a lamp unit 30, an actuator 50, and a control device 60. The actuator 50 transmits the torque of the motor 52 to the lamp unit 30, and can change the orientation of the lamp unit 30 so that the direction of light emission is tilted along a plane VP that is generally parallel to the vertical plane. The control device 60 receives a signal relating to the angle of the emission direction and controls the actuator 50. The control device 60 performs a first control to control the actuator 50 so that the angle of the light emission direction approaches a first angle SA1, which is different from the target angle TA, with respect to the first angle SA1, from the opposite side from the target angle TA. The control device 60 also performs a second control to control the actuator 50 so that the angle of the emission direction approaches the target angle TA, based on the signal relating to the angle of the light emission direction after the first control has been performed.

[0072] In the control device 60, program, and vehicle headlight 1 of this embodiment, the direction in which the angle of the emission direction changes is the same in the first control and the second control performed after the first control. Therefore, rattle between parts can be eliminated by the first control, and the angle of the emission direction can be accurately changed in the second control while being less affected by the rattle. Accordingly, with the control device 60, program, and vehicle headlight 1 of this embodiment, the accuracy of adjusting the emission direction can be improved when bringing the angle of the emission direction closer to the target angle TA.

[0073] In the control device 60 of this embodiment, the first angle SA1 is preset on the side opposite to the direction in which the torque generated in the luminaire unit 30 due to its own weight attempts to change the angle before the first control is performed, with respect to the target angle TA. Therefore, when the angle of the emission direction is brought closer to the first angle SA1, and when the angle of the emission direction is brought closer to the target angle TA, the direction of the torque transmitted from the motor to the luminaire unit 30 is opposite to the direction of the torque due to the weight of the luminaire unit 30. Therefore, with the control device 60 of this embodiment, rattling caused by the weight of the luminaire unit 30 after the first control can be suppressed, and the accuracy of adjusting the direction of light emission can be further improved. Note that the first angle SA1 may be preset on the side opposite to the direction in which the torque generated in the luminaire unit 30 due to its own weight attempts to change the angle before the first control is performed, with respect to the target angle TA. In other words, in this embodiment, the first angle SA1 may be an angle above the target angle TA.

[0074] If the period for which voltage is applied to the motor is shorter than the period of the motor's time constant, the accuracy of the change in the angle of the ejection direction tends to decrease. In the control device 60 of this embodiment, the absolute value of the difference between the first angle SA1 and the target angle TA is greater than or equal to the threshold TH. The threshold TH is the absolute value of the change in the angle of the ejection direction when a predetermined voltage is applied to the motor 52 for a period longer than the motor 52's time constant. Therefore, according to the control device 60 of this embodiment, the period for which voltage is applied to the motor 52 in the second control becomes longer than the period of the motor 52's time constant. Therefore, according to the control device 60 of this embodiment, the accuracy of adjusting the angle of the ejection direction can be ensured. Note that the absolute value of the difference between the first angle SA1 and the target angle TA may be less than the threshold TH.

[0075] Although the present invention has been described above with reference to the above embodiments, the present invention is not limited thereto.

[0076] For example, in the above embodiment, an actuator 50 capable of changing the orientation of the luminaire unit 30 so that the light emission direction is inclined along a plane VP that is generally parallel to the vertical plane was described as an example. However, the actuator 50 only needs to be capable of changing the orientation of the luminaire unit 30 so that the light emission direction is inclined along a predetermined plane by transmitting the torque of the motor 52 to the luminaire unit 30. For example, the configuration for transmitting the torque of the motor 52 to the luminaire unit 30 is not limited. Also, the predetermined plane is not limited to a plane VP that is generally parallel to the vertical plane. For example, the actuator 50 may be capable of changing the orientation of the luminaire unit 30 so that the light emission direction is inclined along a plane that is generally parallel to the horizontal plane. Although a detailed explanation with illustrations is omitted, an example of such an actuator 50 is a configuration that includes an output shaft that extends in the vertical direction and whose upper end is fixed to the lower side of the luminaire unit 30. In this case, the torque of the motor 52 rotates the output shaft around its central axis. With this configuration, the direction of light emitted from the luminaire unit 30 can be adjusted left and right along a plane that is generally parallel to the horizontal plane.

[0077] Furthermore, in the above embodiment, a preset first angle SA1 was used as an example. However, the first angle SA1 may be set by the control device 60 according to the angle of the light emission direction acquired in step S1, that is, the angle of the emission direction before the first control is performed.

[0078] For example, the control device 60 may set a first angle SA1 between the angle of the ejection direction and the target angle TA before performing the first control. With this configuration, if the angle of the ejection direction is on the side of the target angle TA with respect to the first angle SA1, it becomes unnecessary to change the angle of the ejection direction to the opposite side of the target angle TA with respect to the first angle SA1. In other words, the aforementioned pre-control becomes unnecessary, and the time required to adjust the ejection direction can be shortened. The control device 60 may set a first angle SA1 between the angle of the ejection direction and the target angle TA before performing the first control if the absolute value of the difference between the angle of the ejection direction and the target angle TA is twice or more the threshold TH. In this case, it is preferable that the absolute value of the difference between the angle of the ejection direction and the first angle SA1 before performing the first control, and the absolute value of the difference between the target angle TA and the first angle SA1 are greater than or equal to the threshold TH. With this configuration, the period during which voltage is applied to the motor 52 in the first and second control phases becomes longer than the time constant of the motor 52, thereby ensuring accuracy in adjusting the angle of the ejection direction.

[0079] Furthermore, in the adjustment system SY of the above embodiment, the measuring device 110 received light emitted from the luminaire unit 30 to measure the direction of light emission from the luminaire unit 30 and output a signal related to the direction of light emission from the luminaire unit 30 to the control device 60. However, the device for measuring the direction of light emission from the luminaire unit 30 is not limited. For example, as described above, when the direction of light emission changes vertically as the luminaire unit 30 tilts along a surface VP that is roughly parallel to the vertical plane, the tilt angle of the luminaire unit 30 in the vertical direction is also the angle of the direction of light emission in the vertical direction. For this reason, for example, a sensor that tilts along the surface VP together with the luminaire unit 30 and outputs a signal related to the tilt angle of the luminaire unit 30 indirectly measures the angle of the direction of light emission within the surface VP, and the signal output from the sensor is a signal related to the direction of light emission. Therefore, such a sensor may output a signal related to the direction of light emission to the control device 60. An example of such a sensor is a three-axis acceleration sensor attached to the luminaire unit 30.

[0080] Furthermore, in the above embodiment, a vehicle headlight 1 was described as an example of a vehicle lighting device. However, the vehicle lighting device is not limited to a vehicle headlight, and may also be, for example, a road surface drawing device that draws a predetermined image on the road surface with emitted light.

[0081] According to the present invention, a control device, a program, and a vehicle lighting device are provided that can improve the accuracy of adjusting the direction of light emission from a lighting unit, and can be used in fields such as vehicle lighting devices for automobiles.

Claims

1. A control device that receives a signal relating to the angle of the direction of emission of light emitted from a lighting unit and transmits the torque of a motor to the lighting unit to control an actuator capable of changing the orientation of the lighting unit so that the direction of emission is tilted along a predetermined plane, wherein the control device performs a first control to control the actuator so that the angle of the direction of emission approaches a first angle different from a target angle, from the opposite side of the target angle with respect to the first angle, and then performs a second control to control the actuator so that the angle of the direction of emission approaches the target angle based on the signal relating to the angle of emission after the first control.

2. The control device according to claim 1, characterized in that the first angle is set in advance with respect to the target angle, in the direction in which the torque generated in the lighting unit by the weight of the lighting unit would change the angle before the first control was performed.

3. The control device according to claim 1, characterized in that a first angle is set between the angle of the ejection direction and the target angle before performing the first control.

4. The control device according to claim 1, characterized in that the absolute value of the difference between the first angle and the target angle is greater than or equal to a threshold value which is the absolute value of the change in the angle of the output direction when a predetermined voltage is applied to the motor for a period longer than the time constant of the motor.

5. A program executed on a control device that receives a signal relating to the angle of the direction of emission of light emitted from a light fixture unit and transmits the torque of a motor to the light fixture unit to change the orientation of the light fixture unit so that the direction of emission is tilted along a predetermined plane, the program characterized by causing the control device to perform a first control, which involves controlling the actuator to bring the angle of the direction of emission closer to a first angle different from a target angle, using the first angle as a reference, from the opposite side from the target angle side; and a second control, which involves controlling the actuator to bring the angle of the direction of emission closer to the target angle based on the signal relating to the angle of the direction of emission after the first control has been performed.

6. A vehicle light fixture comprising: a light fixture unit; an actuator capable of changing the orientation of the light fixture unit by transmitting the torque of a motor to the light fixture unit so that the direction of light emission is tilted along a predetermined plane; and a control device that receives a signal relating to the angle of the emission direction and controls the actuator, wherein the control device performs a first control to control the actuator so that the angle of the emission direction approaches a first angle different from a target angle, from the opposite side of the target angle with respect to the first angle, and then performs a second control to control the actuator so that the angle of the emission direction approaches the target angle based on the signal relating to the angle of the emission direction after the first control.

7. The vehicle light fixture according to claim 6, characterized in that the predetermined surface is substantially parallel to a vertical plane.

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