Vehicle lighting equipment

Abstract

To provide a vehicle lighting device which enables a user to check a connection state of a number of light sources without complicating wiring.SOLUTION: A vehicle lighting device 10 mounted on a vehicle 1, includes: a control unit 13; and multiple light source units 12 which are beaded and connected to the control unit 13 and are operated according to commands transmitted from the control unit 13. The control unit 13 transmits a connection check command to the multiple light source units 12 during the start and checks the number of the light source units 12 normally connected based on a response command transmitted from the light source units 12 in response to the connection check command.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a vehicle lighting device.

Background Art

[0002] A vehicle lighting device having a function of detecting a failure of a light source is known. For example, Patent Document 1 discloses a vehicle display device provided with a detection circuit for detecting a disconnection of a light source for each drive circuit of the light source.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the vehicle display device of Patent Document 1 has a problem that the wiring becomes more complicated as the number of light sources increases.

[0005] Therefore, an object of the present disclosure is to provide a vehicle display device capable of checking the connection states of a large number of light sources without complicating the wiring.

Means for Solving the Problems

[0006] On one aspect, the following solution means is provided. (1) A vehicle lighting device mounted on a vehicle, comprising a control unit and a plurality of light source units connected in series to the control unit and operating in response to a command transmitted from the control unit. The control unit transmits a connection check command to the plurality of light source units at startup, and checks the number of the light source units that are normally connected based on a response command transmitted from the light source unit in response to the connection check command. (2) In the configuration of (1) above, the control unit confirms the number of light source units that are properly connected, then sends a lighting command to the light source units that have been confirmed to be properly connected to light source units to light up the light source units at a predetermined brightness, and after sending the lighting command, confirms at least one of the voltage value and set brightness value of the light source unit. (3) In the configuration of (1) above, the multiple light source units are divided into groups for each display area, the connection order of the light source units to the control unit is determined on a group basis, and the groups of display areas of higher importance are connected to the upstream side closer to the control unit. (4) In the configuration of (1) above, the plurality of light source units are divided into groups for each display area, the connection order of the light source units to the control unit is determined on a group basis, and the control unit controls only the groups to which all light source units belonging to have been confirmed to be properly connected as targets for normal operation. [Effects of the Invention]

[0007] According to this disclosure, it is possible to provide a vehicle display device that can check the connection status of many light sources without complicating the wiring. [Brief explanation of the drawing]

[0008] [Figure 1] This is a view of the front of the vehicle's passenger compartment from the rear. [Figure 2] This is a diagram showing the configuration of a vehicle lighting system. [Figure 3] This is a diagram showing the configuration of the light source unit. [Figure 4] This flowchart shows the overall flow of fault diagnosis by the control unit. [Modes for carrying out the invention]

[0009] Hereinafter, embodiments of the vehicle lighting device of this disclosure will be described in detail with reference to the attached drawings. The vehicle lighting device of this disclosure can be applied to lighting devices mounted on automobiles, motorcycles, agricultural machinery, construction machinery, ships, etc. In this embodiment, an example will be described in which the vehicle lighting device is a first to fourth display device that displays required information based on various information acquired from the vehicle.

[0010] As shown in Figure 1, the front of the passenger compartment of Vehicle 1 is equipped with a head-up display device (not shown) that displays necessary information based on various information acquired from Vehicle 1, and a vehicle lighting device 10 (see Figure 2).

[0011] The head-up display device is mounted within the instrument panel 2 of vehicle 1. The head-up display device projects display light showing an image onto the windshield 3 of vehicle 1. The occupants of vehicle 1 perceive the reflected light of the display light projected onto the windshield 3 as a virtual image V.

[0012] As shown in Figures 1 and 2, the vehicle lighting device 10 comprises first to fourth display devices 11A to 11D (display areas). The first display device 11A dynamically displays the presence of a pedestrian, for example, when it detects a pedestrian in a blind spot. The second display device 11B and the third display device 11C project display lights LB and LC onto the windshield 3 according to the movement of vehicles or people around the vehicle 1 when they detect such movement. The projection positions of the display lights LB and LC are, for example, near the left and right sides of the virtual image V, allowing for directional display centered on the virtual image V. The fourth display device 11D has a display area with a display width that extends approximately the entire width in the left-right direction, for example, at the front end of the instrument panel 2 or the lower end of the windshield 3. The fourth display device 11D uses this wide display area to display the behavior and state of the vehicle 1 using the movement of light.

[0013] The first to fourth display devices 11A to 11D each include multiple light source units 12. The multiple light source units 12 are connected in a daisy-chain configuration to a single control unit 13 and operate in response to commands transmitted from the control unit 13. In addition, the multiple light source units 12 are connected in parallel to a single power supply unit 14 and operate using the power supplied from the power supply unit 14.

[0014] As such a light source unit 12, for example, an LED unit from ISELED (registered trademark) can be used. As shown in Figure 3, this LED unit is equipped with multiple color LEDs (Light Emitting Diodes) 121R, 121G, and 121B, and an LED controller 122 that drives and controls these LEDs 121R, 121G, and 121B. Unlike individual LEDs, this type of LED unit is manufactured after calibration, so variations in color and brightness can be suppressed. In addition, this type of LED unit is equipped with a temperature sensor (thermistor), and variations in color and brightness due to temperature changes can be suppressed by correction processing using the temperature coefficient.

[0015] Commands for operating the light source unit 12 include commands for turning on the light, checking connections, checking voltage, checking errors, and checking set brightness values.

[0016] A lighting command is a command to light up a specified light source unit 12 in a specified color. The lighting command includes information specifying the gradation of each color LED 121R, 121G, and 121B, and information specifying the light source unit 12 to be lit. For example, the gradation of each color LED 121R, 121G, and 121B is specified in 256 steps. The light source unit 12 to be lit is specified by a number indicating its position relative to the control unit 13.

[0017] The connection confirmation command is a command for confirming that the light source unit 12 is normally connected to the control unit 13. When the light source unit 12 receives the connection confirmation command from the control unit 13 or from the light source unit 12 adjacent to the upstream side (the control unit 13 side), it transmits the connection confirmation command to the light source unit 12 adjacent to the downstream side. If the connection confirmation command can be normally transmitted to the light source unit 12 adjacent to the downstream side, the connection confirmation command is sequentially transmitted to the light source unit 12 on the downstream side. On the other hand, when the connection confirmation command for the light source unit 12 adjacent to the downstream side fails or when there is no light source unit 12 adjacent to the downstream side, a connection confirmation response command is transmitted to the control unit 13. That is, only the last normally connected light source unit 12 transmits a connection confirmation response command to the control unit 13. And since the connection confirmation response command includes information for identifying the last light source unit 12 (a numerical value indicating which one from the control unit 13), it becomes possible for the control unit 13 side to grasp the number of normally connected light source units 12.

[0018] The voltage confirmation command is a command for confirming the voltage values at various locations of the light source unit 12. When the light source unit 12 receives the voltage confirmation command from the control unit 13, it determines whether the voltage values at various locations such as each LED voltage value, regulator voltage value, ground voltage value, etc. are within the normal range, and transmits the determination result to the control unit 13 as a voltage confirmation response command.

[0019] The error confirmation command is a command for confirming various errors (failures) of the light source unit 12. When the light source unit 12 receives the error confirmation command from the control unit 13, it performs various error determinations and transmits the determination result to the control unit 13 as an error confirmation response command.

[0020] The set brightness value confirmation command is a command for confirming whether the various set brightness values (PWM values) of the light source unit 12 are normal. When the light source unit 12 receives the set brightness value confirmation command from the control unit 13, it determines whether the various set brightness values are within the normal range, and transmits the determination result to the control unit 13 as a set brightness value confirmation response command.

[0021] When the control unit 13 is activated in response to an ON operation of the ignition switch of the vehicle 1, it transmits a command to the plurality of light source units 12 to operate the plurality of light source units 12. This operation includes a failure diagnosis operation executed at startup and a normal operation (display operation) executed thereafter. Hereinafter, the failure diagnosis operation, which is a main part of the present disclosure, will be described.

[0022] At startup, the control unit 13 transmits a connection confirmation command to the plurality of light source units 12, and based on the connection confirmation response command transmitted from the light source unit 12 in response to the connection confirmation command, it checks the number of normally connected light source units 12. Specifically, since only the last normally connected light source unit 12 transmits a connection confirmation response command to the control unit 13, based on the information identifying the last light source unit 12, the control unit 13 can grasp the number of normally connected light source units 12. Also, the control unit 13 stores in advance the actual number of connected light source units 12 and compares it with the connection confirmation result to determine whether all the light source units 12 are normally connected. According to such connection confirmation processing, it becomes possible to check the connection status of many light source units 12 without complicating the wiring.

[0023] Also, after checking the number of normally connected light source units 12, the control unit 13 transmits a lighting command to light the light source unit 12 at a predetermined luminance to the light source unit 12 confirmed to be normally connected. Thereafter, the control unit 13 sequentially transmits a voltage confirmation command, a set luminance value confirmation command, and an error confirmation command to the light source unit 12 to which the lighting command has been transmitted. Then, the control unit 13 checks the voltage value, set luminance value, and error of the light source unit 12 based on the voltage confirmation response command, set luminance value confirmation response command, and error confirmation response command sequentially sent back from the light source unit 12. Thereby, the control unit 13 can check not only the connection status of each light source unit 12 but also voltage value abnormalities, set luminance value abnormalities, various errors, etc. of each light source unit 12.

[0024] As shown in Figure 2, the multiple light source units 12 are divided into groups for each display device 11A to 11D (display area), and the connection order of the light source units 12 to the control unit 13 is determined on a group basis. After confirming the connections, the control unit 13 controls only the groups in which all light source units 12 belonging to the group are confirmed to be properly connected, and excludes the other groups from control and keeps them in an off state. This ensures that only the normally functioning display devices 11A to 11D are operated, preventing erroneous displays by the other display devices 11A to 11D.

[0025] As described above, when the connection order of the light source units 12 to the control unit 13 is based on groups of display devices 11A to 11D, it is desirable to connect the groups of display devices 11A to 11D with higher importance to the upstream side, closer to the control unit 13. High importance means, for example, that the information displayed by the display device is of high importance (or urgency). In detail, display device 11A displays warning information about blind spots that the driver cannot see, and is of the highest importance. Next, display devices 11B and 11C display warning information about areas that the driver can see, and are the second most important after display device 11A. Finally, display device 11D is the least important of the display devices 11A to 11D. By doing so, the possibility that high-importance display devices 11A to 11D may become unable to display due to communication failures caused by broken communication lines, etc., can be reduced.

[0026] Next, the overall flow of fault diagnosis by the control unit 13 will be explained with reference to Figure 4.

[0027] As shown in Figure 4, when the ignition switch of the vehicle 1 is turned ON (S101), the control unit 13 sends a connection confirmation command to the connected light source unit 12 and confirms the number of light source units 12 that have been successfully connected (S102). Next, the control unit 13 determines whether the number of successfully connected light source units 12 matches the actual number of connected light source units 12 that have been stored in advance (S103). If the result of this determination is YES, the process proceeds to step S104; otherwise, the process proceeds to step S117.

[0028] When the control unit 13 proceeds to step S104, it sets the variable x, which indicates which light source unit 12 it is, to 1, and also sets the variable N, which indicates the number of times the fault diagnosis has been repeated, to 1, and then proceeds to step S105. In step S105, the control unit 13 sends a lighting command to light up the x-th light source unit 12 in white, and then sequentially executes steps S106 to S108. In step S106, the control unit 13 sends a voltage check command to the x-th light source unit 12, which is lit in white, to check if the voltage values ​​at various points in the x-th light source unit 12 are normal. In step S107, the control unit 13 sends an error check command to the x-th light source unit 12, which is lit in white, to check for any errors in the x-th light source unit 12. In step S108, the control unit 13 sends a set brightness value check command to the x-th light source unit 12, which is lit in white, to check if the set brightness value of the x-th light source unit 12 is normal.

[0029] Subsequently, the control unit 13 determines whether the variable N has reached a predetermined number (for example, 5) (S109). If the result of this determination is NO, the control unit 13 increments the variable N (S110) and then repeats steps S105 to S108. If the control unit 13 determines that the variable N has reached a predetermined number, it determines whether the variable x has reached the number of light source units 12 that are properly connected (S111). If the result of this determination is NO, the control unit 13 increments the variable x (S112) and then repeats steps S105 to S109. If the control unit 13 determines that the variable x has reached the number of light source units 12 that are properly connected, it proceeds to step S113. The reason for repeating the fault diagnosis N times for the same light source unit 12 is to prevent incorrect fault diagnosis due to accidental communication errors.

[0030] In step S113, the control unit 13 determines whether or not there is a light source unit 12 indicating an abnormality. If the result of this determination is YES, it sequentially sends a lighting command to the corresponding light source unit 12, causing the corresponding light source unit 12 to blink in sequence (S114). This allows the user to recognize the light source unit 12 indicating an abnormality. If the control unit 13 determines in step S113 that there is no light source unit 12 indicating an abnormality, it terminates the fault diagnosis (S115) and starts normal operation (S116).

[0031] Furthermore, it is preferable that the light source unit 12, which indicates an abnormality, is illuminated in white when it flashes. The reason for this is that if only one of the LEDs 121R, 121G, or 121B is illuminated, and that LED malfunctions, it will not light up, and the occurrence of an abnormality cannot be notified. In contrast, if the LEDs are illuminated in white, all three LEDs 121R, 121G, and 121B need to be illuminated, so even if any of the LEDs 121R, 121G, or 121B malfunctions, it is possible to notify the occurrence of an abnormality with a light color other than white.

[0032] On the other hand, if the determination result of step S103 is NO and the control unit 13 proceeds to step S117, it performs the same processing as in steps S104 to S113 in steps S117 to S126. After that, the control unit 13 determines the number of light source units 12 for the display devices 11A to 11D to be operated normally, based on the number of normally connected light source units 12 and the number of light source units 12 for each display device 11A to 11D (S127). For example, the number of light source units 12 for the first display device 11A, which is connected furthest upstream to the control unit 13, is A. The number of light source units 12 for the second display device 11B, which is connected next, is B. The number of light source units 12 for the third display device 11C, which is connected next, is C. The number of light source units 12 for the fourth display device 11D, which is connected next, is D. In this case, if the number of normally connected light source units 12 is less than A (S128), the control unit 13 will turn off all light source units 12 of the display devices 11A to 11D during normal operation after the fault diagnosis is completed (S129). Also, if the number of normally connected light source units 12 is A or greater and less than (A+B) (S130), the control unit 13 will turn on the light source unit 12 of the first display device 11A during normal operation after the fault diagnosis is completed (S131). Also, if the number of normally connected light source units 12 is (A+B) or greater and less than (A+B+C) (S132), the control unit 13 will turn on the light source units 12 of the first display device 11A and the second display device 11B during normal operation after the fault diagnosis is completed (S133). Furthermore, if the number of normally connected light source units 12 is (A+B+C) or greater and less than (A+B+C+D) (S134), the control unit 13 will turn on the light source units 12 of the first to third display devices 11A to 11C during normal operation after the fault diagnosis is completed (S135).

[0033] Although each embodiment has been described in detail above, the invention is not limited to any particular embodiment, and various modifications and changes are possible within the scope described in the claims. Furthermore, it is possible to combine all or more of the components of the embodiments described above. [Explanation of symbols]

[0034] 1 vehicle 2. Instrument Panel 3 Windshield 10. Vehicle lighting equipment 11A First display device 11B Second display device 11C Third Display Device 11D Fourth display device 12 Light source units 121R, 121G, 121B LED 122 LED Controller 13 Control Unit 14 Power supply section

Claims

1. A vehicle lighting device mounted on a vehicle, Control unit and The system comprises a plurality of light source units connected in a daisy-chain fashion to the control unit, which operate in response to commands transmitted from the control unit, The control unit sends a connection confirmation command to a plurality of the light source units at startup, and confirms the number of light source units that have been successfully connected based on the response commands sent from the light source units in response to the connection confirmation command. Multiple light source units are divided into groups according to the display area, The connection order of the light source units to the control unit is determined on a group basis. A vehicle lighting device in which the group of display areas of higher importance is connected to the upstream side, closer to the control unit.

2. The vehicle lighting device according to claim 1, wherein the control unit confirms the number of normally connected light source units, sends a lighting command to the light source units confirmed to be normally connected to light source units to light up the light source units at a predetermined brightness, and after sending the lighting command, confirms at least one of the voltage value and set brightness value of the light source unit.

3. Multiple light source units are divided into groups according to the display area, The connection order of the light source units to the control unit is determined on a group basis. The vehicle lighting device according to claim 1, wherein the control unit controls only the group to which all of the light source units belonging to it have been confirmed to be properly connected, as the target of normal operation control.

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