Head lamp system for light distribution variable type vehicle
By introducing a temperature detection device into the vehicle headlight system, the boundary angle of the light range is adjusted in real time, the problem of uneven light caused by temperature changes is solved, and safe and effective light coverage is achieved.
Patent Information
- Application Number
- JP2023150087
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-09-15
- Publication Date
- 2025-03-28
AI Technical Summary
When the temperature changes in existing vehicle headlight systems, it is difficult to effectively adjust the light range and focus, resulting in uneven light and may cause misleading the light of the vehicle ahead.
By introducing a temperature detection device into the vehicle headlight system, the margin angle of the light range is adjusted in real time according to the ambient temperature, ensuring that when the temperature changes, the headlight light range can maximize the misleading of the light of the vehicle in front and maximize the light coverage of the surrounding environment.
It realizes that under temperature changes, the vehicle headlight system can automatically adjust the light range to avoid light misleading, maximize the light coverage range, and ensure safe driving.
Smart Images
Figure 2025042897000001_ABST
Abstract
Description
[Technical field]
[0001] This technology relates to a variable light distribution vehicle headlamp system that can provide a necessary and sufficient light blocking margin against changes in the components of the variable light distribution headlamp unit due to temperature fluctuations. [Background technology]
[0002] FIG. 3 of Patent Document 1 discloses a vehicle headlamp control device that sets a non-illuminated area having a predetermined distance (margin distance) from the edge of the body of the vehicle ahead according to the inter-vehicle distance from the vehicle itself to the vehicle ahead, and illuminates a headlamp light distribution pattern outside of that area. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] JP 2016-159709 A Summary of the Invention [Problem to be solved by the invention]
[0004] As shown in Figures 4 and 5 of Patent Document 1, the vehicle headlamp control device changes the margin interval of the non-illumination range based on the change in the distance between the vehicle and the vehicle ahead, so that even if the illumination range changes due to the change in the distance between the vehicle and the vehicle ahead, headlamp illumination to the vehicle ahead can be avoided. On the other hand, since vehicle headlamps can cause errors in the illumination range and focus due to changes in components caused by changes in environmental temperature, it is desirable to be able to avoid illumination to the vehicle ahead and illuminate the headlamp light distribution pattern to the maximum range avoiding the vehicle ahead, even if errors in the illumination range, etc., occur due to changes in environmental temperature.
[0005] In view of the above problems, the present application provides a variable light distribution vehicle headlamp system that can achieve a necessary and sufficient light blocking margin against changes in the characteristics of components of a variable light distribution headlamp unit due to temperature fluctuations. [Means for solving the problem]
[0006] In a variable light distribution type vehicle headlight system including a variable light distribution type vehicle headlight unit having a projection lens, surrounding vehicle detection means, and a control device, the control device calculates a vehicle detection angle indicating a vehicle detection range of surrounding vehicles detected by the surrounding vehicle detection means, a margin angle that is set as a margin angle within which illumination of the surrounding vehicles is not performed when an illumination error occurs by the variable light distribution type headlight unit, and a shading indication angle that is an angle obtained by adding the margin angle to the vehicle detection angle and indicating a shading range for the surrounding vehicles, and the variable light distribution type headlight unit irradiates a headlight light distribution pattern outside the range of the shading indication angle, the variable light distribution type vehicle headlight preferably has temperature detection means, and the control device preferably changes the margin angle to a maximum illumination margin angle that maximizes the illumination range of the headlight light distribution pattern, based on an environmental temperature of the variable light distribution type vehicle headlight detected by the temperature detection means.
[0007] (Function) When there is a change in the environmental temperature of the variable light distribution headlamp unit, changes also occur in its constituent members, and as a result, the margin angle required to avoid irradiation of surrounding vehicles by the variable light distribution headlamp unit changes. The control device changes the margin angle to the maximum irradiation margin angle based on the environmental temperature of the variable light distribution vehicle headlamp detected by the temperature detection means, so that the variable light distribution vehicle headlamp avoids irradiating surrounding vehicles and irradiates the headlamp light distribution pattern to the widest range around the surrounding vehicles.
[0008] In addition, it is more desirable for the control device of the variable light distribution vehicle headlamp system to set the margin angle to a maximum when the variable light distribution vehicle headlamp is at a high temperature limit temperature, and to reduce the margin angle as the environmental temperature detected by the temperature detection means becomes lower than the high temperature limit temperature.
[0009] When a variable light distribution type vehicle headlamp is designed on the premise that it will not irradiate surrounding vehicles even when the smallest margin angle is set during low temperature use, it is designed to have the largest margin angle at the high temperature usage limit temperature. However, in this case, the lower the environmental temperature of the variable light distribution type vehicle headlamp becomes below the high temperature usage limit temperature, the smaller the margin angle required to avoid irradiating surrounding vehicles becomes, and the larger the excess light blocking range becomes.
[0010] (Function) The control device of the variable light distribution vehicle headlamp system resets the required margin angle to a smaller value as the environmental temperature of the variable light distribution vehicle headlamp detected by the temperature detection means becomes lower than the high temperature operating limit temperature, thereby minimizing the excess shading range and maximizing the illumination range of the headlamp light distribution pattern while avoiding surrounding vehicles.
[0011] Furthermore, it is more desirable for the control device of the variable light distribution vehicle headlamp system to set the margin angle to a maximum when the variable light distribution vehicle headlamp is at its low temperature limit temperature, and to decrease the margin angle as the environmental temperature detected by the temperature detection means becomes higher than the low temperature limit temperature.
[0012] When a variable light distribution type vehicle headlamp is designed on the premise that it will not irradiate surrounding vehicles even when the smallest margin angle is set during high temperature use, it is designed to have the largest margin angle at the low temperature usage limit temperature. However, in this case, the higher the environmental temperature of the variable light distribution type vehicle headlamp becomes above the low temperature usage limit temperature, the smaller the margin angle required to avoid irradiating surrounding vehicles becomes, and the excess light blocking range increases.
[0013] (Function) The control device of the variable light distribution vehicle headlamp system resets the required margin angle to a smaller value as the environmental temperature of the variable light distribution vehicle headlamp detected by the temperature detection means becomes higher than the low temperature limit temperature, thereby minimizing the excess shading range and maximizing the illumination range of the headlamp light distribution pattern while avoiding surrounding vehicles.
[0014] Moreover, it is more preferable that the variable light distribution type headlamp unit of the variable light distribution type vehicle headlamp system is an LED array.
[0015] (Function) Even if there is a change in the environmental temperature of the variable light distribution type vehicle headlamp, the LED array avoids surrounding vehicles without creating unnecessary light-blocking areas, and irradiates the surrounding area with the maximum headlamp light distribution pattern.
[0016] Moreover, it is preferable that the projection lens of the variable light distribution type vehicle headlamp system is made of resin.
[0017] (Function) Even if changes in the environmental temperature of the variable light distribution type vehicle headlamp cause deformation or other changes in the plastic projection lens, the variable light distribution type vehicle headlamp avoids surrounding vehicles without creating unnecessary light-blocking areas, and illuminates the surrounding area with the maximum possible headlight light distribution pattern.
[0018] Moreover, it is preferable that the projection lens of the variable light distribution type vehicle headlamp system be made of a combination of resin and glass.
[0019] (Function) Even if changes such as deformation occur in the projection lens, which is made of a combination of glass and resin, due to changes in the environmental temperature of the variable light distribution vehicle headlamp, the variable light distribution vehicle headlamp avoids surrounding vehicles without creating unnecessary light-blocking areas, and illuminates the surrounding area with the maximum headlight light distribution pattern. Effect of the Invention
[0020] According to the variable light distribution vehicle headlamp system, even if a change in the environmental temperature of the variable light distribution vehicle headlamp causes the set margin angle to become an angle that blocks light beyond the range that should be blocked, the control device corrects the angle to the maximum irradiation margin angle in accordance with the environmental temperature, so that the light blocking range is kept to the minimum range that avoids surrounding vehicles, and the headlamp light distribution pattern is illuminated as close as possible to the surrounding vehicles.
[0021] According to the variable light distribution type vehicle headlamp system, when it is designed to maximize the margin angle at the high operating limit temperature, the excess light blocking range can be reduced and the maximum range of the headlamp light distribution pattern can be irradiated to the surrounding vehicles while avoiding direct irradiation of the surrounding vehicles.
[0022] According to the variable light distribution type vehicle headlamp system, when it is designed to maximize the margin angle at the low operating limit temperature, the excess shading range can be reduced and the maximum range of the headlamp light distribution pattern can be irradiated to the surrounding vehicles while avoiding direct irradiation of the surrounding vehicles.
[0023] According to the variable light distribution type vehicle headlamp system, regardless of changes in the environmental temperature of the variable light distribution type vehicle headlamp, it is possible to irradiate the surroundings with the maximum headlamp light distribution pattern while avoiding surrounding vehicles.
[0024] According to the variable light distribution vehicle headlight system, even if changes in the environmental temperature of the variable light distribution vehicle headlight cause deformation or other changes in the plastic projection lens, the maximum headlight light distribution pattern can be projected onto the surrounding area while avoiding nearby vehicles.
[0025] According to the variable light distribution vehicle headlight system, even if changes such as deformation occur in the projection lens, which is made of a combination of resin and glass, due to changes in the environmental temperature of the variable light distribution vehicle headlight, the maximum headlight light distribution pattern can be projected onto the surrounding area while avoiding surrounding vehicles. [Brief description of the drawings]
[0026] [Figure 1] 1 is a front view of an embodiment of a variable light distribution type vehicle headlamp; FIG. [Diagram 2] 2A is a vertical cross-sectional view of a variable light distribution headlamp unit taken along line II in FIG. 1. FIG. 2B is a vertical cross-sectional view showing a modified example of the projection lens. [Diagram 3] 1 is a block diagram of an embodiment of a variable light distribution type vehicle headlamp system; [Figure 4] FIG. 4 is an explanatory diagram of a light distribution pattern produced by a variable light distribution headlamp. [Diagram 5] 1 is an explanatory diagram of a margin angle in a typical variable light distribution type vehicle headlamp system. [Figure 6] 5 is an explanatory diagram of margin angle adjustment by the variable light distribution type vehicle headlamp system of the present embodiment based on low temperature use. FIG. [Figure 7] 5 is an explanatory diagram of margin angle adjustment by the variable light distribution type vehicle headlamp system of the present embodiment, based on high temperature use. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0027] A preferred embodiment of the present invention will be described below with reference to Fig. 1 to Fig. 7. In each figure, the directions of the road as seen by the driver of a vehicle (not shown) equipped with a variable light distribution type vehicle headlamp used in a variable light distribution type vehicle headlamp system are described as (upper: lower: left: right: front: rear = Up: Lo: Le: Ri: Fr: Re).
[0028] The variable light distribution type vehicle headlamp (1, 1') shown in Figures 1 and 2(a) is an example of a pair of left and right headlamp, and includes a lamp body (2, 2') having an opening on the vehicle front side, and a transparent or semi-transparent front cover (3, 3') that closes the opening. Inside a lamp chamber S formed inside the lamp body (2, 2') and the front cover (3, 3'), a variable light distribution type headlamp unit (4, 4'), a low beam lamp unit (5, 5'), an aiming bracket 6 (not shown for the right side), a swivel unit (7, 7'), a plurality of aiming screws (8, 8'), an in-vehicle camera 10 (equipped only to the variable light distribution type headlamp unit 4 for the left side), an extension reflector 11 (not shown for the right side), a control device 13 (not shown for the right side), and a temperature sensor 14 (temperature detection means) are housed. In this embodiment, the right-hand variable light distribution vehicle headlamp 1' has a shape that is bilaterally symmetrical to the left-hand variable light distribution vehicle headlamp 1, and has a common configuration with the left-hand variable light distribution vehicle headlamp 1 except for the right-hand variable light distribution headlamp unit 4'.
[0029] The variable light distribution type left headlamp unit 4 (first unit) shown in Figures 1 and 2(a) is composed of a μLED array 9 consisting of a large number of fine LED light sources 9a arranged vertically and horizontally, a swivel bracket 12, a control device 13, a temperature sensor 14, and a projection lens module 15, which is a projection lens.
[0030] 2(a), the μLED array 9 and the projection lens module 15 are mounted on the swivel bracket 12. The μLED array 9 is attached to the upright wall portion 12b extending upward from the rear end of the swivel bracket 12 so as to face forward, and the projection lens module 16 is attached near the front end of the swivel bracket 12 so as to face the μLED array 9.
[0031] The projection lens module 15 in FIG. 2(a) has a first lens 15a made of glass and having a biconvex shape from the rear to the front, a second lens 15b made of resin and having a biconcave shape, a third lens 15c made of resin and having a plano-convex shape, a lens holder 15d, and a base portion 15e. The first to third lenses (15a to 15c) are fixed to the lens holder 15d in a state in which they are arranged in order from the rear with a gap between them. The first lens 15a is arranged to face the μLED array 9 at the rear. The lens holder 15d is mounted on the swivel bracket 12 via the base portion 15e. The number and shape of the lenses constituting the projection lens module 15 and the number of LED light sources 9a of the μLED array 9 are not limited to those shown in FIG. 2(a). Furthermore, the combination of resin and glass in the first to third lenses (15a to 15c) of the projection lens module 15 is not limited to the combination shown in the figure.
[0032] The swivel bracket 12 in Fig. 2(a) is mounted integrally on the motor drive shaft 7a that automatically rotates around an axis L10 extending vertically of the swivel unit 7, and a support shaft 15f that is coaxial (axis L10) with the motor drive shaft 7a is provided on the upper surface of the lens holder 15d. The swivel unit 7 is supported by the lower end 6a of the aiming bracket 6 in a state where the swivel bracket 12 is supported, and the support shaft 15f of the lens holder 15d is rotatably supported in a support hole 6c of the upper end 6b of the aiming bracket 6. The lower end 6a is integrated with the upper end 6b via the base end 6d on which the control device 13 is mounted, and the base end 6d is attached to the lamp body 2 so as to be freely tiltable by a plurality of aiming screws 8 (three in this embodiment).
[0033] As shown in FIG. 3, the μLED array 9 of the variable light distribution headlamp unit 4, the swivel unit 7, the temperature sensor 14, a storage unit 17 such as a memory, and the photographing unit 18 are electrically connected to the control device 13 to construct a variable light distribution vehicle headlamp system 100. The many LED light sources 9a of the μLED array 9 are independently controlled to be turned on and off for each LED light source 9a by the control device 13. The control device 13 detects the temperature inside the lamp chamber S via the temperature sensor 14 attached to the lower surface of the upper end portion 6b of the aiming bracket 6. The storage unit 17 stores in advance a correspondence table of margin angles required in accordance with the environmental temperature. The photographing unit 18, which is a surrounding vehicle detection means, is composed of an in-vehicle camera 10 provided facing forward on the left variable light distribution vehicle headlamp 1 shown in FIG. 1, and an image processing device 19. The control device 13 analyzes the image or video captured by the in-vehicle camera 10 connected via the image processing device 19, and acquires the shape and position of the preceding vehicle FC (surrounding vehicle) and the like as shown in FIG. 4 to FIG. 7. The surrounding vehicle detection means is not limited to one including the vehicle-mounted camera 10, and may be composed of an external street camera or the like connected by a communication means (not shown).
[0034] The μLED array 9 and projection lens module 15 integrated on the swivel bracket 12 in Fig. 2(a) rotate together around axis L10 with the rotation of the motor drive shaft 7a of the swivel unit 7 controlled by the control device 13, and swivel left and right. The inside of the lamp chamber excluding the low beam lamp unit 5 in Fig. 1 and the first to third lenses (15a to 15c) of the projection lens module 15 is concealed from the front by the extension reflector 11 in Fig. 2(a).
[0035] 2(b) shows a projection lens module 16 which is a modified example of the projection lens module 15. The projection lens module 16 may be a projection lens module consisting of a single resin plano-convex projection lens, instead of a configuration in which a plurality of glass lenses and resin lenses are arranged as in the projection lens module 15. Furthermore, the projection lens module 16 may be a biconvex or biconcave lens in addition to a plano-convex lens, or may be a glass lens.
[0036] Next, with reference to Figure 4, we will explain a vehicle headlight with variable light distribution that can block only the headlight's illumination range that causes glare on preceding vehicles and oncoming vehicles. With reference to Figure 5, we will explain a vehicle headlight with variable light distribution in which a generous shading range is set by using a margin angle so that glare is not caused to preceding vehicles or oncoming vehicles even if fluctuations (illumination errors) occur in the headlight's illumination range (range to be shaded) due to temperature fluctuations in the vehicle headlight with variable light distribution.
[0037] FIG. 4 shows a light distribution pattern that is illuminated in front of the vehicle by the variable light distribution vehicle headlamp (1, 1') shown in FIG. 1. The symbol ADP indicates the headlamp display of the variable light distribution pattern illuminated by the variable light distribution headlamp unit (4, 4'), and the symbol Lp indicates the low beam light distribution pattern displayed below the variable light distribution pattern ADP by the low beam lamp unit (5, 5'). As shown in FIG. 4, when a leading vehicle FC is present in front of the vehicle, the control device 13 of FIG. 3 that controls the variable light distribution headlamp unit (4, 4') acquires the shape and position of the leading vehicle FC by the on-board camera 10, acquires the left and right end positions of the leading vehicle FC, and turns off only the LED light sources 9a that irradiate the inside of the straight lines S1, S2 indicating the left and right end positions of the leading vehicle FC among the many LED light sources 9a that irradiate the variable light distribution pattern ADP, thereby preventing glare to the leading vehicle and displaying the headlamp in the widest range.
[0038] However, in reality, in the variable light distribution headlamp unit (4, 4'), changes in the characteristics of components such as a plastic projection lens may occur as the environmental temperature changes, causing a change in the illumination range. Therefore, even if the position of the preceding vehicle FC and an oncoming vehicle (not shown) are blocked at a specified temperature, the change in the illumination range due to temperature change may result in insufficient shading, and glare light toward the preceding vehicle FC, etc. may not be properly avoided.
[0039] For this reason, as shown in Figure 5, one approach is to expand the shading range to outside the vehicle detection position by the vehicle-mounted camera 10, and set a margin angle so that glare light is not irradiated onto the preceding vehicle FC even if the illumination range of the LED array expands due to temperature changes, thereby realizing a shading range with a margin for temperature changes using a variable light distribution headlamp system.
[0040] Specifically, as shown in Fig. 5, the preceding vehicle FC is photographed by an on-board camera 10 mounted on the vehicle MC, and the distance D1 from the vehicle MC to the preceding vehicle FC measured along a straight line L0 passing through the centers of the vehicle MC and the preceding vehicle FC, and the vehicle detection angles θ1 and θ2 from the center of the straight line L0 of the vehicle MC to the left and right end positions of the preceding vehicle FC (the left and right ends P1 and P2 of the rear tires are detected as an example, but the detection of the ends is not limited to this) are detected. Then, the preceding vehicle detection range L1 on the left side from the straight line L0 (D1 x tan θ1) and the preceding vehicle detection range L2 on the right side from the straight line L0 (D1 x tan θ2) are generated. On the other hand, even if the ranges L1 and L2 are shielded to the left and right from the vehicle center line L0, glare light may occur because the irradiation range changes to the inside of the preceding vehicle FC due to temperature changes.
[0041] 5, in a conventional variable light distribution headlamp that performs light blocking with a margin in response to temperature changes, the margin angles, i.e., the margin angles that allow no illumination of a preceding vehicle, etc., are set to θ3 and θ4 on the left and right, respectively, and the light blocking instruction angle to the μLED array 9 by the control device 13 is set to (θ1+θ3) to the left and (θ2+θ4) to the right, blocking the range of L1+L3 to the left and L2+L4 to the right from the center line L0 of the vehicle. In this case, even if the variable light distribution pattern ABP1 on the left side avoiding the preceding vehicle FC moves to the right by a maximum distance of L3 due to the focus shift caused by the maximum temperature change, and the variable light distribution pattern ABP2 on the right side moves to the left by a maximum distance of L4 due to the focus shift caused by the maximum temperature change, no glare is generated at the preceding vehicle FC.
[0042] However, although such shading control is useful in that it does not cause glare to the preceding vehicle FC when the temperature fluctuation is maximum, a shading range that is that large is not required when the temperature fluctuation is less than the maximum fluctuation. Therefore, if the shading range is made larger than necessary, the variable light distribution pattern cannot be projected all the way to the very edge of the preceding vehicle, which causes a problem in that the area around the preceding vehicle is darkened.
[0043] In consideration of such problems with light shading control, the light shading control by the variable light distribution vehicle headlamp system of this embodiment shown in Figures 6 and 7 enables a variable light distribution pattern to be irradiated up to the very limit of the preceding vehicle even if there is a temperature fluctuation. The variable light distribution vehicle headlamp system of this embodiment adjusts the margin angle according to the change in the irradiation range and the change in the required margin angle that occur with temperature fluctuation.
[0044] With reference to FIG. 6, the margin angle adjustment when temperature fluctuation occurs in the variable light distribution type vehicle headlamp system of this embodiment based on low temperature use will be described.
[0045] The variable light distribution headlamp system in Fig. 6 is designed to generate an optimal focus for the variable light distribution pattern when used at a low temperature such as 20°C, and to prevent glare from being irradiated to the preceding vehicle FC if only L1 to the left and L2 to the right are blocked when used at 20°C. In this case, as the environmental temperature increases, the focal point shifts due to changes in the characteristics of components caused by expansion and deformation of the projection lens, etc., and the irradiation range moves inward (in the d1 direction) to generate glare at the preceding vehicle FC, so the left and right margin angles θ3 and θ4 are set to be maximum at the high temperature operating limit temperature (for example, 70°C, etc.). Values measured in advance for each temperature are stored in the storage unit 17 in Fig. 3 for the margin angles at which the variable light distribution pattern can be irradiated as close as possible to the preceding vehicle.
[0046] In the case of the vehicle MC, when the vehicle is used at or below the high-temperature limit temperature, neither the focus shift nor the shift in the illumination range occurs as much as when the vehicle is at the high-temperature limit temperature. Therefore, the control device 13 of the variable light distribution illumination system of this embodiment periodically detects the temperature in the lamp chamber S as the temperature of the variable light distribution headlamp unit (4, 4') by the temperature sensor 14. If the detected temperature of the variable light distribution headlamp unit (4, 4') is below the high-temperature limit temperature, the margin angle corresponding to the detected temperature is read from the storage unit 17, and the margin angles θ3 and θ4 are reduced from the maximum angles to appropriate angles corresponding to the temperature decrease, thereby turning on the LED light sources 9a corresponding to the unnecessary extinguished range and narrowing the light-blocking range. In addition, when the temperature of the variable light distribution type headlamp unit (4, 4'), which is periodically detected, further decreases, the control device 13 reduces the margin angle to an appropriate margin angle stored in the memory unit 17 in accordance with the ambient temperature, thereby narrowing the shading range, and when the temperature of the variable light distribution type headlamp unit (4, 4'), which is detected, increases, the margin angle to an appropriate margin angle stored in the memory unit 17 in accordance with the ambient temperature, and turns off the LED light sources 9a within the corresponding range, thereby expanding the shading range.
[0047] In this way, even if the temperature of the variable light distribution headlamp unit (4, 4') rises or falls, light blocking control can be performed within a minimum range based on an optimal margin angle in either case, so that a variable light distribution pattern can be irradiated up to the very limit of the vicinity of the preceding vehicle even if there is a temperature fluctuation.
[0048] Next, with reference to FIG. 7, a margin angle adjustment when temperature fluctuation occurs in the variable light distribution type vehicle headlamp system of this embodiment based on high temperature use will be described.
[0049] The variable light distribution headlamp system of Fig. 7 is designed to generate an optimal focus for the variable light distribution pattern when used at a high temperature such as 70°C, and to prevent glare from being irradiated to the preceding vehicle FC if only L1 to the left and L2 to the right are blocked when used at 70°C. In this case, as the environmental temperature decreases, the projection lens and other components expand and deform, causing the focus to shift, and the irradiation range to move inward (in the d2 direction), causing glare to the preceding vehicle FC. Therefore, the left and right margin angles θ3 and θ4 are set to be maximum at the low temperature operating limit temperature (e.g., 20°C, etc.). The margin angles at which the variable light distribution pattern can be irradiated as close as possible to the preceding vehicle are measured in advance for each temperature and stored in the memory unit 17 of Fig. 3.
[0050] In the subject vehicle MC, when the vehicle is used at or above the low-temperature limit temperature, there is no focus shift or shift in the illumination range as much as when the vehicle is used at or above the low-temperature limit temperature. Therefore, the control device 13 of the variable light distribution illumination system of this embodiment periodically detects the temperature in the lamp chamber S as the temperature of the variable light distribution headlamp unit (4, 4') by the temperature sensor 14. If the detected temperature of the variable light distribution headlamp unit (4, 4') is equal to or above the low-temperature limit temperature, the control device 13 reads out the margin angle corresponding to the detected temperature from the storage unit 17, and reduces the margin angles θ3 and θ4 from the maximum angles to appropriate angles corresponding to the temperature rise, thereby turning on the LED light sources 9a corresponding to the unnecessary extinguished range and narrowing the light-blocking range. In addition, when the temperature of the variable light distribution headlamp unit (4, 4'), which is periodically detected, further rises, the control device 13 reduces the margin angle to an appropriate margin angle stored in the memory unit 17 in accordance with the ambient temperature, thereby narrowing the shading range, and when the temperature of the variable light distribution headlamp unit (4, 4'), which is detected, decreases, the control device 13 expands the margin angle to an appropriate margin angle stored in the memory unit 17 in accordance with the ambient temperature, and turns off the LED light sources 9a within the corresponding range, thereby expanding the shading range.
[0051] In this way, even if the temperature of the variable light distribution headlamp unit (4, 4') rises or falls, light blocking control can be performed within a minimum range based on an optimal margin angle in either case, so that a variable light distribution pattern can be irradiated up to the very limit of the vicinity of the preceding vehicle even if there is a temperature fluctuation. [Explanation of symbols]
[0052] 1, 1' Variable light distribution type vehicle headlamp 4, 4' Variable light distribution headlamp unit 9μ LED array 10. In-vehicle camera (means for detecting surrounding vehicles) 13 Control device 14 Temperature sensor (temperature detection means) 15 Projection lens module (projection lens) 15a Glass biconvex first lens 15b Resin double-concave second lens 15c Plastic plano-convex third lens 16a Plastic plano-convex lens 18 Photographing unit (surrounding vehicle detection means) 19 Image processing device (surrounding vehicle detection means) 100 Variable light distribution vehicle headlamp system ABP1, ABP2 Headlight distribution pattern outside the shaded angle range θ1, θ2 Vehicle detection angles θ3,θ4 Margin angle θ1+θ3, θ2+θ4 Shading indication angle
Claims
1. The present invention provides a variable light distribution vehicle headlamp including a variable light distribution headlamp unit having a projection lens, a surrounding vehicle detection means, and a control device, the control device calculates a vehicle detection angle indicating a vehicle detection range of a surrounding vehicle detected by the surrounding vehicle detection means, a margin angle set as a margin angle for not irradiating the surrounding vehicle when an irradiation error occurs by the variable light distribution headlamp unit, and a shading indication angle which is an angle obtained by adding the margin angle to the vehicle detection angle, and which indicates a shading range for the surrounding vehicle; In the variable light distribution vehicle headlamp system, the variable light distribution headlamp unit irradiates a headlamp light distribution pattern outside the range of the shading indication angle, The variable light distribution type vehicle headlamp has a temperature detection means, The control device includes: a variable light distribution type vehicle headlight system, characterized in that the margin angle is changed to a maximum irradiation margin angle that maximizes the irradiation range of the headlight light distribution pattern, based on the environmental temperature of the variable light distribution type vehicle headlight detected by the temperature detection means.
2. The control device includes: The margin angle is set to a maximum value at a high temperature usage limit temperature of the variable light distribution type vehicle headlamp, 2. The variable light distribution type vehicle headlamp system according to claim 1, wherein the margin angle is decreased as the environmental temperature detected by the temperature detection means becomes lower than a high temperature limit temperature.
3. The control device includes: The margin angle is set to a maximum value at a low temperature limit of the variable light distribution type vehicle headlamp; 2. The variable light distribution type vehicle headlamp system according to claim 1, wherein the margin angle is decreased as the environmental temperature detected by the temperature detection means becomes higher than a low temperature limit temperature.
4. 4. The variable light distribution type vehicle headlamp system according to claim 1, wherein the variable light distribution type headlamp unit is an LED array.
5. 4. The variable light distribution type vehicle headlamp system according to claim 1, wherein the projection lens is made of a resin.
6. 4. The variable light distribution type vehicle headlamp system according to claim 1, wherein the projection lens is made of a combination of resin and glass.
Citation Information
Patent Citations
Vehicular headlamp control unit
JP2016159709A