JP7315111B2 - variable light distribution system - Google Patents

Description

The present invention relates to a variable light distribution system capable of changing the illumination range of headlamps that illuminate the front of a vehicle.

An existing headlamp technology is ADB (variable beam distribution headlamp). The function of the ADB is to block the light of the forward vehicle so that the high beam light does not directly hit the forward vehicle when the forward vehicle is detected at night. Also, a technique has been proposed in which light distribution control is performed to control the irradiation direction and range according to the running direction or steering angle of the vehicle and the vehicle speed (see, for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 2000-238576

However, the ADB function alone has room for improvement in order to keep the driver's visibility better at night.
The variable light distribution system of the present invention has been devised in view of such problems, and one of the purposes thereof is to keep the visibility of the driver better at night. In addition to this purpose, it is also another object of the present invention to achieve functions and effects that are derived from each configuration shown in the embodiments for carrying out the invention described later and that cannot be obtained by the conventional technology.

(1) The variable light distribution system disclosed herein includes: a first light emitting unit that emits a high beam in a direction substantially parallel to a road surface in front of a vehicle; a second light emitting unit that emits a low beam in a direction downward from the direction in which the high beam is emitted; a variable light distribution unit that emits an auxiliary high beam so as to interpolate between the irradiation range of the high beam and the irradiation range of the low beam; a vehicle speed sensor that detects the speed of the vehicle; wherein the control device controls the variable light distribution unit so that the lower the vehicle speed, the closer the position to the vehicle becomes the irradiation range of the auxiliary high beam.

(2) The illumination range of the high beam, the low beam, and the auxiliary high beam is defined by the illumination direction, which is the vertical direction, and the vehicle width direction length, which is the extent of the illumination in the vehicle width direction. Preferably, the control device controls the variable light distribution unit so that the illumination direction of the auxiliary high beam becomes downward as the vehicle speed decreases.
(3) Preferably, the control device controls the variable light distribution unit so that the irradiation direction of the auxiliary high beam is downward with respect to the horizontal direction.
(4) It is preferable that the control device controls the variable light distribution unit so that the closer the position is to the vehicle, the longer the length of the irradiation range of the auxiliary high beam in the vehicle width direction.
(5) It is preferable that the control device controls the variable light distribution unit so that the length of the auxiliary high beam in the vehicle width direction is longer than the length of the low beam in the vehicle width direction, at least when the vehicle speed is at or below a predetermined vehicle speed.
(6) It is preferable that the control device turns off the first light emitting unit when a traveling vehicle exists in front of the vehicle.
(7) Preferably, the control device automatically changes the irradiation range of the auxiliary high beam according to the vehicle speed detected by the vehicle speed sensor.

According to the disclosed variable light distribution system, the auxiliary high beam can keep the driver's visibility better at night.

1 is a front view of a vehicle equipped with a variable light distribution system according to an embodiment; FIG. FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1; FIG. 3 is a diagram corresponding to FIG. 2 for explaining the irradiation pattern for each vehicle speed, (a) at high speed, (b) at medium speed, and (c) at low speed. FIG. 2 is a plan view (viewed from above) of a traveling road for explaining the irradiation range for each vehicle speed, (a) at high speed, (b) at medium speed, and (c) at low speed or stop. FIG. 4 is a diagram for explaining the irradiation range for each vehicle speed when there is a preceding vehicle, and is a diagram showing the state of the road as seen from the driver, (a) at high speed, (b) at medium speed, and (c) at low speed. FIG. 4 is a diagram for explaining the irradiation range for each vehicle speed when there is no preceding vehicle, and is a diagram showing the state of the road as seen from the driver, (a) at high speed, (b) at medium speed, and (c) at low speed.

A variable light distribution system as an embodiment will be described with reference to the drawings. The embodiments shown below are merely examples, and there is no intention to exclude various modifications and application of techniques not explicitly described in the embodiments below. Each configuration of this embodiment can be modified in various ways without departing from the gist thereof. Also, they can be selected or combined as needed.

In the following description, the forward direction of the vehicle is defined as the front of the vehicle (simply referred to as "forward"), the backward direction is defined as the rear of the vehicle (simply referred to as "rear"), and left and right are defined with reference to the front. The left-right direction of the vehicle is also referred to as the "vehicle width direction", and the front-rear direction of the vehicle is simply referred to as the "front-rear direction". In addition, the vertical direction is defined by taking the direction of gravity downward and vice versa upward.

[1. composition]
As shown in FIG. 1, the variable light distribution system of the present embodiment is a system that varies the irradiation range of the headlamps 10 according to the vehicle speed of the vehicle 1, and includes the headlamps 10, a control device 20, and a vehicle speed sensor 30 that detects the vehicle speed of the vehicle 1.

The headlamp 10 has a first light emitting part 11 that emits a high beam in a direction substantially parallel to the road surface in front of the vehicle 1, and a second light emitting part 12 that emits a low beam downward from the direction in which the high beam is emitted. These two types of light-emitting units 11 and 12 have conventionally well-known structures (for example, optical units). The headlamp 10 further comprises a variable light distribution unit 13 for emitting an auxiliary high beam so as to interpolate between the high beam irradiation range and the low beam irradiation range. Note that the left and right headlamps 10 are configured similarly (symmetrically).

The control device 20 is one of the electronic control devices [ECU (Electronic Control Unit)] mounted on the vehicle 1, and is an electronic device equipped with a processor and a memory. A processor is, for example, a microprocessor such as a CPU (Central Processing Unit) or MPU (Micro Processing Unit), and a memory is, for example, a ROM (Read Only Memory), a RAM (Random Access Memory), a non-volatile memory, or the like. The contents of the control performed by the control device 20 are recorded and stored in the memory as firmware and application programs, and when the programs are executed, the contents of the programs are developed in the memory space and executed by the processor.

The control device 20 automatically changes the irradiation range of the auxiliary high beam according to the vehicle speed detected by the vehicle speed sensor 30 . More specifically, the control device 20 controls the variable light distribution unit 13 so that a position closer to the vehicle 1 becomes an irradiation range as the vehicle speed becomes slower. In other words, the illumination range is defined by the illumination direction, which is the vertical direction, and the vehicle width direction length, which is the width of the illumination in the vehicle width direction. Further, the control device 20 of the present embodiment controls the variable light distribution unit 13 so that the irradiation direction of the auxiliary high beam is below the horizontal direction.

2 is a cross-sectional view taken along the line AA of FIG. 1. Arrow FR shown in the figure indicates the front of the vehicle 1, and arrow LH indicates the left side of the vehicle 1. As shown in FIG. As shown in FIG. 2, the variable light distribution unit 13 of the present embodiment includes a plurality of (here, three) light emitting portions 13a, 13b, and 13c (hereinafter also referred to as “light emitting portions 13a to 13c”), and a reflector 14 that reflects the light emitted from these light emitting portions 13a to 13c. The light emitting units 13a to 13c are composed of LED lights, for example, and are arranged side by side in the longitudinal direction of the vehicle. Each of the light emitting units 13a to 13c is turned on and off according to the vehicle speed. Since the light emitted from the light emitting portions 13a to 13c of the headlamp 10 is reflected by the reflector 14, the headlamp 10 illuminates an irradiation range corresponding to the vehicle speed.

The light-emitting portion 13a positioned behind the vehicle is a light-emitting portion for high vehicle speed that lights up at a high vehicle speed. The light-emitting portion 13c positioned in front of the vehicle is a light-emitting portion for low vehicle speed that lights up when the vehicle is traveling at a low speed. A light emitting portion 13b located between the two light emitting portions 13a and 13c is a middle vehicle speed light emitting portion that lights up at a middle vehicle speed. The high vehicle speed light emitting portion 13a is arranged at the focal position, and the middle vehicle speed light emitting portion 13b and the low vehicle speed light emitting portion 13c are arranged away from the focal position.

As shown in FIG. 3( a ), when the light emitting portion 13 a for high vehicle speed is turned on, the light of the LED light is reflected by the reflector 14 and illuminates a distant place in front of the vehicle 1 away from the vehicle 1 . As shown in FIG. 3B, when the middle vehicle speed light emitting portion 13b is turned on, the light of the LED light is reflected by the reflector 14 and travels obliquely (diagonally laterally) to the front of the vehicle 1, illuminating the side of the vehicle 1. As a result, the length in the vehicle width direction is increased, and at the same time, the irradiation direction is changed so that a position near the vehicle 1 is irradiated. As shown in FIG. 3C, when the low vehicle speed light emitting portion 13c is turned on, the light of the LED light is reflected by the reflector 14 and travels more obliquely (more obliquely laterally) in front of the vehicle, illuminating the side of the vehicle 1. As a result, the length in the vehicle width direction is further increased, and at the same time, the irradiation direction is changed so that a position closer to the vehicle 1 is irradiated.
In the examples shown in FIGS. 3(b) and 3(c), the light from the LED lights is reflected by the reflector 14 and travels obliquely to the front of the vehicle 1. Therefore, the amount of light emitted from the auxiliary high beam in front of the vehicle 1 decreases, but the amount of light is ensured because this portion is illuminated with the low beam.

The control device 20 of the present embodiment changes the irradiation range of the auxiliary high beam by switching the three light emitting portions 13a to 13c of the variable light distribution unit 13 on and off. FIGS. 4A to 4C are plan views (viewed from above) of the running road for explaining the irradiation range for each vehicle speed, showing high speed, medium speed, low speed, or stop, respectively. Also, here, a case where there is an oncoming vehicle 80 in front of the vehicle 1 across the intersection is shown. Reference symbol R1 in the drawing indicates the irradiation range of the high beam, reference symbol R2 indicates the irradiation range of the low beam, and reference symbol R3 indicates the irradiation range of the auxiliary high beam. Both the irradiation range R1 of the high beam and the irradiation range R2 of the low beam are constant regardless of the vehicle speed. Further, the lengths in the vehicle width direction of the irradiation ranges R1 and R2 of the high beam and the low beam are substantially the same.

The controller 20 of the present embodiment brings the illumination range R3 of the auxiliary high beam closer to the vehicle 1 as the vehicle speed decreases. That is, the irradiation direction is changed downward. Further, the control device 20 controls the variable light distribution unit 13 so that the vehicle width direction length of the auxiliary high beam irradiation range R3 with respect to the vehicle width direction length of the low beam irradiation range R2 becomes longer at a position closer to the vehicle 1. - 特許庁That is, the irradiation range R3 of the auxiliary high beam shown in FIG. 4B is wider in the vehicle width direction than that shown in FIG. 4A, and the irradiation range R3 of the auxiliary high beam shown in FIG. 4C is wider in the vehicle width direction than that shown in FIG. 4B. In FIGS. 4A to 4C, the low beam irradiation range R2 is partially cut off so that the driver of the oncoming vehicle 80 is less likely to feel glare.

FIGS. 5(a) to 5(c) are diagrams for explaining the irradiation range for each vehicle speed when there is a preceding vehicle 90, and show the state of the road as seen from the driver. 5(a) shows when the vehicle speed V is higher than the first predetermined vehicle speed V1 (V1<V), FIG. 5(b) shows when the vehicle speed V is lower than the first predetermined vehicle speed V1 and higher than a second predetermined vehicle speed V2 (V2<V≦V1), and FIG. 5(c) shows when the vehicle speed V is lower than the second predetermined vehicle speed V2 (V≦V2). ) and the preceding vehicle 90 gradually become shorter. In FIGS. 5A to 5C, the irradiation range R1 when the high beam is irradiated is indicated by a chain double-dashed line. 6(a) to (c) are diagrams for explaining the irradiation range for each vehicle speed when there is no preceding vehicle 90, and correspond to FIGS. 5(a) to (c), respectively. FIGS. 5A to 5C are the same as FIGS. 6A to 6C except for the presence or absence of the preceding vehicle 90 and the presence or absence of high beam irradiation.

The control device 20 of the present embodiment turns off the first light emitting unit 11 and does not irradiate the high beam when there is a traveling vehicle (for example, the preceding vehicle 90) in front of the vehicle 1 . As shown in FIGS. 4A to 4C, when there is an oncoming vehicle 80 as a traveling vehicle in front of the vehicle 1, the first light emitting unit 11 may be turned off so as not to irradiate the high beam.

As shown in FIGS. 5A and 6A, when the vehicle speed V of the vehicle 1 is high, the auxiliary high beam is emitted so that the irradiation range R3 of the auxiliary high beam partially overlaps the irradiation range R1 of the high beam and the irradiation range R2 of the low beam. At this time, the vehicle width direction length of the irradiation range R3 of the auxiliary high beam is substantially the same as the vehicle width direction length of each of the high beam and low beam irradiation ranges R1 and R2. That is, when the vehicle speed is high, the auxiliary high beam particularly illuminates the distant front side of the vehicle 1 .

As shown in FIGS. 5B and 6B, when the vehicle speed V of the vehicle 1 is moderate, the auxiliary high beam is projected slightly downward so that the irradiation range R3 of the auxiliary high beam overlaps the irradiation range R2 of the low beam more than the irradiation range R1 of the high beam. At this time, the vehicle width direction length of the irradiation range R3 of the auxiliary high beam is longer than the vehicle width direction length of each of the high beam and low beam irradiation ranges R1 and R2. Further, the irradiation range R3 of the auxiliary high beam shown in FIGS. 5(b) and 6(b) is wider in the vehicle width direction than that shown in FIGS. 5(a) and 6(a). That is, at medium vehicle speed, the auxiliary high beam illuminates the front of the vehicle 1 as well as the sides thereof.

As shown in FIGS. 5(c) and 6(c), when the vehicle speed V of the vehicle 1 is low, the auxiliary high beam is projected further forward (at a position closer to the vehicle 1) so that the irradiation range R3 of the auxiliary high beam substantially encompasses the irradiation range R2 of the low beam. At this time, the vehicle width direction length of the irradiation range R3 of the auxiliary high beam is longer than the vehicle width direction length of each of the high beam and low beam irradiation ranges R1 and R2. Further, the irradiation range R3 of the auxiliary high beam shown in FIGS. 5(c) and 6(c) is wider in the vehicle width direction than that shown in FIGS. 5(b) and 6(b). That is, when the vehicle speed is low, the auxiliary high beam mainly illuminates the sides of the vehicle 1 .

[2. action, effect]
Therefore, according to the variable light distribution system described above, since the auxiliary high beam is irradiated so as to interpolate between the irradiation range R1 of the high beam and the irradiation range R2 of the low beam, it is possible to illuminate the area between the two irradiation ranges R1 and R2, which has conventionally been difficult to illuminate. Further, the irradiation range R3 of the auxiliary high beam is controlled according to the vehicle speed V, and the lower the vehicle speed V, the more the irradiation direction is directed downward and the front side (position closer to the vehicle 1) is illuminated, so that the visibility of the driver at night can be appropriately maintained better. In addition, the slower the vehicle speed V, the longer the length of the irradiation range R3 in the vehicle width direction, and the more lateral sides of the vehicle 1 are illuminated. From this point, the visibility of the driver at night can be maintained better.

Specifically, the control device 20 additionally irradiates a distant area in front of the vehicle with the auxiliary high beam at high speeds, so that a distant field of vision can be ensured. Further, at medium speed, additional irradiation is performed by the auxiliary high beam so as to interpolate between the irradiation range R1 of the high beam and the irradiation range R2 of the low beam in front of the vehicle. In addition, when the vehicle is running at low speeds, the auxiliary high beam additionally irradiates the side near the front of the vehicle, so that visibility can be ensured when the vehicle is approaching an intersection, for example.

In the variable light distribution system described above, the variable light distribution unit 13 is controlled by the control device 20 so that the irradiation direction of the auxiliary high beam is below the horizontal direction. Therefore, even if the auxiliary high beam continues to be emitted when there is another vehicle traveling ahead of the vehicle 1, the driver of the other vehicle is less likely to be dazzled.

In the above-described variable light distribution system, the variable light distribution unit 13 is controlled by the control device 20 so that the closer the position is to the vehicle 1, the longer the vehicle width direction length of the auxiliary high beam irradiation range R3 with respect to the vehicle width direction length of the low beam irradiation range R2. Therefore, the slower the vehicle speed, the closer the vehicle 1 is illuminated, and the wider the width of the vehicle becomes brighter, so that the driver's field of vision can be maintained even better.

According to the variable light distribution system described above, when there is a traveling vehicle in front of the vehicle 1, the first light emitting part 11 is turned off, so that the high beam is not emitted, and it is possible to reduce glare to the drivers of other vehicles. Also, even in this case, the auxiliary high beam is emitted, so the driver's field of vision can be maintained better.

[3. others]
The configuration of the variable light distribution system described above is an example. For example, the number of light emitting units provided in the variable light distribution unit 13 is not limited to three, and the arrangement thereof is not limited to that described above. Further, instead of changing the irradiation range R3 of the auxiliary high beam by changing the ON/OFF pattern of the light emitting portion provided in the variable light distribution unit 13, the reflector 14 may be made movable. The method of changing the irradiation range R3 of the auxiliary high beam is not limited to the above configuration.
In the variable light distribution system described above, the irradiation range is controlled in three stages of high speed, medium speed, and low speed according to the vehicle speed V, but the irradiation range may be controlled in two stages, may be controlled in more stages, or may be controlled in a stepless manner.

Each irradiation range R1, R2 of the high beam and the low beam is an example, and is not limited to the configuration described above. Also, the lighting/lighting of the high beam does not have to be the configuration described above. Further, the irradiation range R3 of the auxiliary high beam may be controlled at least in the front-rear position, and the length in the vehicle width direction may be constant regardless of the vehicle speed.

This application is based on Japanese Patent Application No. 2020-175983 filed on October 20, 2020, the contents of which are incorporated herein by reference.

1 vehicle 10 headlamp 11 first light emitting part 12 second light emitting part 13 variable light distribution unit 13a light emitting part for high vehicle speed 13b light emitting part for middle vehicle speed 13c light emitting part for low vehicle speed 14 reflector 20 control device 30 vehicle speed sensor 80 oncoming vehicle (running vehicle)
90 Leading vehicle (running vehicle)
R1 High beam irradiation range R2 Low beam irradiation range R3 Auxiliary high beam irradiation range

Claims (7)

a first light emitting unit that emits a high beam in a direction substantially parallel to the road surface in front of the vehicle;
a second light emitting unit that emits a low beam downward from the direction in which the high beam is emitted;
a variable light distribution unit that irradiates an auxiliary high beam so as to interpolate between the irradiation range of the high beam and the irradiation range of the low beam;
a vehicle speed sensor that detects the vehicle speed of the vehicle;
a control device that changes the irradiation range of the auxiliary high beam according to the vehicle speed detected by the vehicle speed sensor;
The variable light distribution system, wherein the control device controls the variable light distribution unit so that a position closer to the vehicle as the vehicle speed decreases becomes the illumination range of the auxiliary high beam. The irradiation range of the high beam, the low beam and the auxiliary high beam is defined by the irradiation direction, which is the vertical direction of irradiation, and the vehicle width direction length, which is the width of the irradiation in the vehicle width direction,
2. The variable light distribution system according to claim 1, wherein said control device controls said variable light distribution unit so that said irradiation direction of said auxiliary high beam becomes downward as said vehicle speed becomes slower. 3. The variable light distribution system according to claim 2, wherein said control device controls said variable light distribution unit so that said irradiation direction of said auxiliary high beam is downward with respect to a horizontal direction. 4. The variable light distribution system according to claim 2, wherein the controller controls the variable light distribution unit such that the closer the position to the vehicle, the longer the length of the auxiliary high beam in the vehicle width direction. 5. The variable light distribution system according to claim 4, wherein the control device controls the variable light distribution unit so that the length of the auxiliary high beam in the vehicle width direction is longer than the length of the low beam in the vehicle width direction, at least when the vehicle speed is medium to low speeds equal to or lower than a predetermined vehicle speed. 6. The variable light distribution system according to any one of claims 1 to 5, wherein the control device turns off the first light emitting unit when a vehicle is running ahead of the vehicle. The variable light distribution system according to any one of claims 1 to 6, wherein the control device automatically changes the illumination range of the auxiliary high beam according to the vehicle speed detected by the vehicle speed sensor.

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