Vehicle lighting device

Abstract

To provide a vehicle lighting device capable of reducing deterioration and maintaining visibility.SOLUTION: A vehicle lighting device includes: a light emission unit that illuminates a road surface in the outside of an entrance of a vehicle to be opened and closed; and a control unit that detects brightness of the outside when the entrance is opened, and causes the light emission unit to light when the brightness in the outside is equal to or less than a predetermined value. The control unit may change the brightness of the light emission unit according to the brightness of the outside. The light emission unit has the maximum value of brightness of the light emission unit. The control unit causes the light emission unit with brightness of the maximum value when the brightness of the outside is equal to or greater than the predetermined value.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a vehicle lighting device that illuminates a road surface outside a vehicle entrance / exit. [Background technology]

[0002] 2. Description of the Related Art Conventionally, lighting devices that illuminate a road surface so that a passenger or other person can recognize that a door of a vehicle is open are known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Utility Model Application Publication No. 6-75896 Summary of the Invention [Problem to be solved by the invention]

[0004] The above-mentioned lighting devices are not only turned on and illuminate the road surface, but also project designs with design and visibility, such as a vehicle logo. As a result, the brightness of the lighting device increases, and there is a risk that the materials forming the design, such as the film, will deteriorate due to the heat of the light source.

[0005] The present disclosure has been made in consideration of the above circumstances, and has an object to provide a vehicle lighting device that can reduce deterioration and maintain visibility. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, the vehicle lighting device of the present invention includes a light-emitting unit that illuminates the road surface outside of a vehicle's entrance / exit that opens and closes, and a control unit that detects the brightness of the outside when the entrance is open, and turns on the light-emitting unit when the brightness of the outside is below a predetermined value. Effect of the Invention

[0007] In the vehicle lighting device according to the present invention, deterioration can be reduced and visibility can be maintained. [Brief description of the drawings]

[0008] [Figure 1] 1 is an explanatory diagram of a state in which a door of a vehicle equipped with a vehicle lighting device according to an embodiment of the present invention is open; [Diagram 2] Cross-sectional view of the light-emitting part. [Diagram 3] FIG. 2 is a functional block diagram of the vehicle lighting device. [Figure 4] 5 is a flowchart illustrating a lighting control process executed by a control unit. [Diagram 5] FIG. 2 is an explanatory diagram conceptually showing the relationship between the environmental illuminance and the illuminance and lighting time of a lighting device. [Figure 6] 5 is a graph showing changes over time in environmental illuminance and illuminance of a light-emitting unit. [Figure 7] 6 is a graph showing changes over time in environmental illuminance and illuminance of a light-emitting unit, and explaining a state when the light-emitting unit is turned off. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] An embodiment of the vehicle lighting device of the present disclosure will be described with reference to the attached drawings. The vehicle lighting device of the present disclosure can be mounted on vehicles such as automobiles, agricultural machines, and construction machines, in which the boarding entrance is opened and closed by a door that opens and closes with respect to the vehicle body. In this embodiment, the vehicle on which the vehicle lighting device is mounted is an automobile, and an example in which the boarding entrance is opened and closed by a door will be described.

[0010] FIG. 1 is an explanatory diagram of a state in which a door 3 of a vehicle 1 equipped with a vehicle lighting device 10 according to the present embodiment is open. FIG. 2 is a cross-sectional view of the light-emitting section 20. FIG. 3 is a functional block diagram of the vehicle lighting device 10. As shown in FIG.

[0011] In the following description, “front”, “rear”, “upper”, “lower”, “right” and “left” follow the definitions of “Fr.”, “Re.”, “To.”, “Bo.”, “R” and “L” in FIG. 1.

[0012] The vehicle lighting device 10 (lighting device 10) is mounted on a vehicle 1 having a vehicle body 2 and a door 3 that opens and closes about an axis that is aligned substantially in the vertical direction with respect to the vehicle body 2 as a fulcrum.

[0013] The lighting device 10 mainly includes a light-emitting unit 20, a control unit 30, an open / close sensor 35, and an illuminance sensor .

[0014] The light emitting unit 20 is a so-called courtesy light, and is disposed, for example, below the interior of the door 3 on the driver's seat side of the vehicle body 2. When the door 3 is opened, the light emitting unit 20 illuminates the road surface outside the entrance / exit 4, thereby brightly lighting up the feet of passengers getting on and off, and notifying drivers, etc. of other vehicles approaching the vehicle from behind (hereinafter, passengers and drivers, etc. are referred to as "visitors") that the door 3 is open.

[0015] As shown in FIG. 2, the light-emitting section 20 has a lens barrel 21, a light source 23, first to fourth lenses 24 to 27 (hereinafter sometimes simply referred to as “lenses 24 to 27”), and a film unit 29.

[0016] The lens barrel 21 is a cylindrical member having an open end 21a at one end located below when placed on the door 3, and a bottom 21b at the other end located above. The lens barrel 21 is fixed to a storage space formed in the door 3 via, for example, a support member 21c. The lens barrel 21 has a support structure 21d on its inner peripheral surface so as to support the light source 23, the first lens 24, the film unit 29, the second lens 25, the third lens 26, and the fourth lens 27 in that order from the bottom 21b toward the open end 21a.

[0017] The light source 23 has a substrate and an LED (Light Emitting Diode) mounted on the substrate, which lights up in white, red, blue, etc. The luminance (illuminance) of the light source 23 is controlled by the voltage value applied thereto.

[0018] The lenses 24 to 27 are required optical members such as condenser lenses and projection lenses, which are made of transparent resin such as PMMA or polyester.

[0019] The film unit 29 has a design film and a holder for holding the design film. The design film forms the design 5 according to the design 5 projected by the light emitting unit 20 by transmitting the light of the light source 23.

[0020] The control unit 30 is composed of, for example, a vehicle ECU (Electronic Control Unit) that comprehensively controls the vehicle 1, and a dedicated control board for controlling the light emitting unit 20. The control unit 30 has a lighting control unit 31 and an illuminance control unit 32.

[0021] The lighting control unit 31 and the illuminance control unit 32 control the on / off and illuminance of the light source 23 based on the detection results of the open / close sensor 35 and the illuminance sensor 36 (details will be described later).

[0022] The opening / closing sensor 35 detects the opening / closing state of the door 3. The opening / closing sensor 35 supplies the detection result to the control unit 30.

[0023] The illuminance sensor 36 is disposed, for example, on the door 3, and detects the illuminance of the road surface below the door 3, which is the brightness outside the vehicle 1, as the environmental illuminance. The illuminance sensor 36 supplies the detection result to the control unit 30.

[0024] Here, the light source 23 generates heat as it emits light, and the amount of heat generated increases proportionately with increasing brightness. This may have a negative effect on the lenses 24-27 and filters of the light-emitting unit 20. For example, the heat-resistant temperature of typical optical components used for the lenses 24-27 is about 120 degrees. The heat-resistant temperature of the design film is about 100 degrees. In particular, unlike the lenses 24-27 that transmit all light, the design film also has the function of blocking light to generate the design 5, and is therefore more susceptible to heat generation and deterioration than the lenses 24-27. For this reason, the design film in particular may discolor when it becomes hotter than its heat-resistant temperature, and there is a risk that the desired design 5 may not be formed.

[0025] Therefore, the lighting device 10 in this embodiment solves the problem of heat generation by controlling the on / off and illuminance of the light-emitting unit 20 according to the environmental illuminance. A specific description will be given below using a flowchart.

[0026] FIG. 4 is a flowchart illustrating the illumination control process executed by the control unit 30. As shown in FIG.

[0027] In step S1, the lighting control unit 31 determines whether or not the door 3 is open based on the detection result of the opening / closing sensor 35. When the lighting control unit 31 determines that the door 3 is not open but is closed (NO in step S1), the lighting control unit 31 waits until the door 3 is opened. On the other hand, when the lighting control unit 31 determines that the door 3 is open (YES in step S1), in step S2, the illuminance control unit 32 acquires the environmental illuminance from the illuminance sensor 36. The illuminance control unit 32 acquires the illuminance as the outside brightness, but may acquire a numerical value other than the illuminance as long as the brightness can be evaluated.

[0028] In step S3, the illuminance control unit 32 determines whether the environmental illuminance is greater than the maximum illuminance (predetermined value). The maximum illuminance is, for example, a value equivalent to the limit illuminance (maximum brightness of the light-emitting unit 20) which is the maximum value of illuminance that the light-emitting unit 20 can achieve. This maximum illuminance may be set appropriately and is not limited to the limit illuminance of the light-emitting unit 20. If the illuminance control unit 32 determines that the environmental illuminance is greater than the maximum illuminance (YES in step S3), the illuminance of the light-emitting unit 20 is insufficient to allow the viewer to recognize the lighting even if the light-emitting unit 20 is turned on, and the process ends without turning on the light.

[0029] On the other hand, if the illuminance control unit 32 determines that the environmental illuminance is equal to or lower than the maximum illuminance (NO in step S3), in step S4, the lighting control unit 31 causes the light-emitting unit 20 (light source 23) to emit light. At this time, the control unit 30 may turn on the light-emitting unit 20 at a constant illuminance, but from the viewpoint of suppressing heat generation from the light source 23, it is preferable to change the illuminance of the light-emitting unit 20 according to the environmental illuminance. Here, Fig. 5 is an explanatory diagram conceptually showing the relationship between the environmental illuminance and the illuminance and lighting time of the light-emitting unit 20.

[0030] For example, the lower the environmental illuminance, the darker the lighting device 10 is, the lower the illuminance of the lighting device 10 is. Also, in a range where the environmental illuminance is equal to or lower than the maximum illuminance, the brighter the environmental illuminance is, the higher the illuminance of the lighting device 10 is. On the other hand, when the environmental illuminance is greater than the maximum illuminance, the control unit 30 does not turn on the lighting device 10 even when the door 3 is opened, because the lighting is unlikely to be recognized even if it is turned on.

[0031] In step S5, the illuminance control unit 32 continues to obtain the environmental illuminance from the illuminance sensor 36 even after lighting, and determines whether or not there is a change in the environmental illuminance. If the illuminance control unit 32 determines that the illuminance has changed (YES in step S5), then in step S6, it determines whether or not the environmental illuminance is greater than the maximum illuminance, similar to step S3 of the illuminance determination. If the illuminance control unit 32 determines that the environmental illuminance is equal to or less than the maximum illuminance (NO in step S6), then in step S7, the lighting control unit 31 causes the light-emitting unit 20 to emit light at an illuminance according to the environmental illuminance, for example, according to the relationship between the environmental illuminance and the illuminance of the light-emitting unit 20 shown in FIG.

[0032] On the other hand, when the illuminance control unit 32 determines that the environmental illuminance is greater than the maximum illuminance (YES in step S6), in step S8, the illuminance of the light-emitting unit 20 is set to the limit illuminance. That is, no matter how high the environmental illuminance is, the illuminance control unit 32 maintains the illuminance at the limit illuminance without increasing the illuminance accordingly. Note that, when the illuminance control unit 32 determines that the environmental illuminance is greater than the maximum illuminance, the illuminance control unit 32 may turn off the light-emitting unit 20.

[0033] After steps S7 and S8, in step S9, the lighting control unit 31 determines whether a predetermined time has elapsed since the light-emitting unit 20 started to be turned on. The predetermined time may be a constant value regardless of the illuminance of the light-emitting unit 20, but it is preferable to set the predetermined time so that the higher the illuminance of the light-emitting unit 20, the shorter it is, and the lower the illuminance is, from the viewpoint of suppressing heat generation of the light-emitting unit 20, as shown in FIG. 5. Here, FIG. 6 is a graph showing the time change of the environmental illuminance and the illuminance of the light-emitting unit 20. The lighting control unit 31 can set the time from turning on to turning off the light-emitting unit 20 to the time until the integrated value of the illuminance of the light-emitting unit 20 and the time (the area of ​​the hatched area in FIG. 6) reaches a predetermined value, for example. When the lighting control unit 31 determines that the predetermined time has elapsed (YES in step S9), for example, when it determines that the integrated value has reached a predetermined value, in step S10, the lighting control unit 31 turns off the light-emitting unit 20 and ends the process.

[0034] 7 is a graph showing the time change of the environmental illuminance and the illuminance of the light-emitting unit 20, and explaining the state when the light-emitting unit 20 is turned off. The lighting control unit 31 may turn off the light instantaneously when the lighting time has passed a predetermined time, but may also create a visual effect by gradually reducing the illuminance after the predetermined time t1 has arrived, as shown in FIG 7. The lighting control unit 31 may also start reducing the illuminance from a time t1 before the time when the predetermined time is expected to arrive, and turn off the light completely when the predetermined time t2 arrives.

[0035] When the lighting control unit 31 determines that the predetermined time has not elapsed (NO in step S9), it returns to step S5 of illuminance change determination and repeats the subsequent processes until the predetermined time has elapsed. Note that in the repeated processes from step S5 of illuminance change determination to step S9 of determining that the predetermined time has elapsed, the vehicle 1 may repeatedly go in and out of the shade and the sun, causing the environmental illuminance to change frequently. In this case, in order to prevent frequent changes in the illuminance of the light-emitting unit 20, the illuminance control unit 32 may obtain an average illuminance over a predetermined time period in the past (e.g., several seconds), and change the illuminance of the light-emitting unit 20 when this average illuminance has changed by a predetermined value or more.

[0036] Such an illumination device 10 turns on the light-emitting unit 20 only when the environmental illuminance is equal to or lower than the illuminance at which a viewer can visually recognize the illumination. Therefore, the illumination device 10 can suppress unnecessary light emission, thereby suppressing heat generation from the light source 23 and suppressing thermal deterioration of the design filter and lenses 24 to 27. Therefore, the illumination device 10 can reduce deterioration due to heat and maintain the visibility of the design 5.

[0037] In addition, since the lighting device 10 changes the brightness of the light-emitting unit 20 according to the ambient illuminance, it is possible to suppress unnecessary high-illuminance light emission, and at the same time, when the ambient illuminance is high, it is possible to increase the illuminance to ensure visibility.

[0038] Furthermore, the lighting device 10 is configured to turn on the light-emitting unit 20 at the limit illuminance even when the environmental illuminance is high. Also, the lighting device 10 sets the time from turning on to turning off the light according to the illuminance of the light-emitting unit 20. Therefore, the lighting device 10 can reduce lighting at high illuminance that may cause thermal degradation and lighting at high illuminance for long periods of time, thereby suppressing thermal degradation.

[0039] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0040] 1 vehicle 2. Body 3 Door 4. Boarding and alighting 10 Vehicle lighting devices (lighting devices) 20 Light emitting part 21 Telescope tube 21a Open end 21b bottom 21c Support member 21d Support structure 23 Light source 24 First Lens 25 Second Lens 26 Third Lens 27 Fourth Lens 29 Film Unit 30 Control section 31 Lighting control unit 32 Illuminance control section 35 Open / Close Sensor 36 Illuminance sensor

Claims

1. A light emitting unit that illuminates a road surface outside an opening and closing door of a vehicle; A vehicle lighting device comprising: a control unit that detects an external brightness when the boarding / alighting door is open, and turns on the light-emitting unit when the external brightness is equal to or lower than a predetermined value.

2. The vehicle lighting device according to claim 1 , wherein the control unit changes a brightness of the light emitting unit, the brightness being a brightness of the light emitting unit, in response to the external brightness.

3. the light-emitting portion has a maximum brightness value of the light-emitting portion, The vehicle lighting device according to claim 2 , wherein the control unit turns on the light emitting unit at the maximum brightness when the external brightness is equal to or greater than a predetermined value.

4. The control unit turns off the light emitting unit after a predetermined time has elapsed since the light emitting unit was turned on, The vehicle lighting device according to claim 1 , wherein the predetermined time is set so that the brighter the light-emitting portion is, the shorter the predetermined time is, and the darker the light-emitting portion is, the longer the predetermined time is.

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