JP2019117724A - Vehicular lighting fixture - Google Patents

Abstract

To provide a vehicular lighting fixture capable of suppressing a driver of an oncoming car feeling the glare, without reducing light for light distribution in a low region during low beam irradiation.SOLUTION: A vehicular lighting fixture A1 includes: a first headlight (low beam LEDs 31-34 and reflection surfaces 11-14 of a reflector 1); a second headlight (high beam LEDs 35, 36 and reflection surfaces 15, 16 of the reflector 1) for radiating light further upward than the first headlight; and a control circuit for switching between a state for performing light distribution for high beam and a state for performing light distribution for low beam. In the case of a state for performing light distribution for low beam, the control circuit allows the first headlight to perform light irradiation and allows the second headlight to perform light irradiation in which brightness is lowered.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vehicular lamp that emits light in front of a vehicle.

  A vehicular lamp which reflects light from a light source with a reflector and illuminates the front of the vehicle is switched between a traveling headlamp (so-called high beam) and a passing headlamp (so-called low beam). And at the time of low beam irradiation, light distribution for illuminating an overhead sign (overhead sign) is required separately from light distribution irradiated to a low region. It is known to use light reflected by a part of the reflecting surface of the reflector at the time of low beam irradiation for light distribution for overhead signs (see, for example, Patent Document 1).

JP, 2014-216202, A

  However, when the light reflected by a part of the reflecting surface of the reflector is used for the light distribution for the overhead sign, a part of the light from the light source for the low beam is used, and the low region of the low beam (below There is a problem that the light for light distribution in the “lower region” is reduced accordingly. Further, the light distribution for the overhead sign is light with high brightness because the light from the light source for the low beam is reflected in a narrow range. Therefore, when the driver of the oncoming oncoming vehicle is irradiated, there is also a problem that the driver feels glare.

  The present invention has been conceived under the above-mentioned circumstances, and at the time of low beam irradiation, without reducing the light for light distribution in the low region, and feeling dazzling to the driver of the oncoming vehicle It is an object of the present invention to provide a vehicular lamp which can be suppressed.

  In order to solve the above-mentioned subject, in the present invention, the following technical measures are taken.

  The vehicle lamp provided by the present invention includes a first headlamp, a second headlamp for emitting light above the first headlamp, and a state for performing light distribution for high beam. And a control circuit for switching to a state of performing light distribution for low beam, wherein the control circuit is configured to irradiate light to the first headlight when the light distribution for low beam is performed. It is characterized in that the second headlight is made to emit light whose brightness is reduced.

  According to the present invention, in the case of low-beam light distribution, the second headlight, which emits light above the first headlight, is caused to emit light whose brightness is reduced. Therefore, when light distribution for low beam is performed, it is possible to form a light distribution pattern for overhead sign in the second headlight. The second headlight emits light whose brightness is reduced, so it is possible to suppress the driver of the oncoming vehicle from feeling glare. In addition, since the light of the second headlight is used for the light distribution for the overhead sign, the light of the first headlight is not reduced.

  Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings.

It is a schematic front view of the vehicle lamp concerning this embodiment. (A) is the sectional view on the AA line in FIG. 1, (b) is a sectional view on the BB line in FIG. It is a functional block diagram of a portion concerning control in a vehicular lamp concerning this embodiment. It is a schematic front view which shows the modification of the vehicle lamp which concerns on this embodiment.

  Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. In the following description, front, rear, upper, lower, left, and right indicate directions when the vehicle lamp is attached to the vehicle.

  FIGS. 1 to 3 are views for explaining a vehicle lamp A1 according to the present embodiment. FIG. 1 is a schematic front view of a vehicular lamp A1. FIG. 2A is a cross-sectional view taken along the line AA in FIG. FIG. 2B is a cross-sectional view taken along the line B-B in FIG. FIG. 3 is a functional block diagram of a portion related to control in the vehicular lamp A1. The vehicle lamp A1 shown in FIGS. 1 and 2 is a headlight which is disposed on the front left side of the vehicle and emits light to the front. In addition, the structure of the headlight arrange | positioned on the front right side of a vehicle is also the same as that of vehicle lamp A1, and becomes what left-right reversed vehicle lamp A1.

  The vehicular lamp A1 includes a reflector 1, a substrate 2, low beam LEDs 31 to 34, high beam LEDs 35 and 36, drive circuits 41 to 43, and a control circuit 5. In addition, although vehicle lamp A1 is actually provided with the housing and the outer lens, description is abbreviate | omitted in FIG. 1 and FIG. The housing is made of, for example, a synthetic resin, and an opening is provided at least on the front side of the vehicle. The outer lens transmits light, for example, made of synthetic resin, and covers the opening of the housing. The reflector 1, the substrate 2, the low beam LEDs 31 to 34, the high beam LEDs 35 and 36, the drive circuits 41 to 43, and the control circuit 5 are housed in a lamp chamber formed by a housing and an outer lens. The shape and material of the housing and the outer lens are appropriately designed. In the following, the low beam LEDs 31 to 34 and the high beam LEDs 35 and 36 are collectively referred to as “LEDs 31 to 36”.

  The reflector 1 reflects the light emitted from the LEDs 31 to 36 toward the front of the vehicle, and is fixed to the housing by a support member (not shown). The reflector 1 has a concave shape that is open on the front side of the vehicle. The reflector 1 is integrally formed of, for example, a synthetic resin, and at least the surface of the inner portion is subjected to a reflection treatment by aluminum deposition or silver coating.

  The reflector 1 is provided with a protrusion 17 inside. The projecting portion 17 is disposed on the inner side of the reflector 1 above the center in the vertical direction, and extends to the left and right ends on the inner side of the reflector 1. A space 17 a is provided on the back side of the protrusion 17. Further, in the projecting portion 17, three holes 17b opening upward from the space 17a and three holes 17c opening downward are formed. The end of the substrate 2 on which the LEDs 31 to 36 are mounted is inserted into the space 17 a. The holes 17 b and the holes 17 c are arranged in alignment with the positions of the LEDs 31 to 36.

  The inside of the reflector 1 is divided into upper and lower parts by the projecting part 17, and the upper part and the lower part are each divided into three in the left-right direction. A reflective surface 11 is formed on the left side of the upper portion. A reflective surface 12 is formed on the left side of the lower portion. A reflective surface 13 is formed at the center of the upper portion. A reflective surface 14 is formed at the center of the lower portion. A reflective surface 15 is formed on the right side of the upper portion. A reflective surface 16 is formed on the right side of the lower portion. Each of the reflective surfaces 11 to 16 is formed on the basis of a paraboloid of revolution with the LEDs 31 to 36 as focal positions, and is divided into a plurality of surfaces. The light distribution is controlled by the direction of each divided surface. The shape and the material of the reflector 1 are not limited.

  The substrate 2 is, for example, a substantially rectangular plate, and the LEDs 31 to 36, the drive circuits 41 to 43, and the control circuit 5 are mounted. The substrate 2 is fixed to the housing by a support member in a state where a part of the substrate 2 is inserted into the space 17 a of the reflector 1. The substrate 2 includes an upper surface 2a and a lower surface 2b facing in the thickness direction. Low beam LEDs 31, 33 and high beam LED 35 are mounted on the upper surface 2a, and low beam LEDs 32, 34 and high beam LED 36 are mounted on the lower surface 2b. Further, drive circuits 41 to 43 are also mounted on the upper surface 2a. The drive circuits 41 to 43 may be mounted on the lower surface 2 b. Further, although not shown, the substrate 2 also includes electronic components for realizing the control circuit 5, electronic components constituting a power supply circuit, a heat dissipation member for releasing heat generated by the LEDs 31 to 36, and the like. It is mounted.

  The low beam LEDs 31 to 34 and the high beam LEDs 35 and 36 are light emitting diodes that emit white light. The low beam LEDs 31 and 33 and the high beam LED 35 are mounted on the upper surface 2 a of the substrate 2 with the light emitting surface facing up. The low beam LEDs 32, 34 and the high beam LED 36 are mounted on the lower surface 2b of the substrate 2 with the light emitting surface facing down. In the present embodiment, each of the LEDs 31 to 36 is one LED, but may be a plurality of LEDs. Also, the shape of the LED is not limited.

  The drive circuits 41 to 43 are supplied with power from the power supply circuit, and supply drive current to the respective LEDs 31 to 36 based on pulse signals input from the control circuit 5. The drive circuit 41 supplies drive current to the low beam LEDs 31 and 32, the drive circuit 42 supplies drive current to the low beam LEDs 33 and 34, and the drive circuit 43 supplies drive current to the high beam LEDs 35 and 36. The drive circuit 41 may supply the same drive current to the low beam LEDs 33 and 34 without providing the drive circuit 42.

  The drive circuit 41, the low beam LEDs 31 and 32, and the reflection surfaces 11 and 12 of the reflector 1 constitute a first unit (see FIG. 2A). The low beam LEDs 31 and 32 emit light in accordance with the drive current supplied from the drive circuit 41. The light emitted from the low beam LED 31 is reflected by the reflective surface 11 through the hole 17 b and is irradiated to the front of the vehicle. In addition, the light emitted from the low beam LED 32 is reflected by the reflection surface 12 through the hole 17 c and is irradiated to the front of the vehicle. The reflecting surfaces 11 and 12 are designed to diffuse and irradiate light to a wide irradiation area of a low area in a low beam light distribution pattern. Thereby, the first unit forms a wide irradiation area of the low area in the light distribution pattern of the low beam.

  The drive circuit 42, the low beam LEDs 33 and 34, and the reflecting surfaces 13 and 14 of the reflector 1 constitute a second unit. The low beam LEDs 33 and 34 emit light in accordance with the drive current supplied from the drive circuit 42. The light emitted from the low beam LED 33 is reflected by the reflective surface 13 through the hole 17 b and is irradiated to the front of the vehicle. In addition, the light emitted from the low beam LED 34 is reflected by the reflection surface 14 through the hole 17 c and is irradiated to the front of the vehicle. The reflective surfaces 13 and 14 are designed to concentrate and irradiate light to a narrow irradiation area for forming a cutoff line in the low beam light distribution pattern. Thereby, the second unit forms a narrow irradiation area of the low area in the light distribution pattern of the low beam. The first unit and the second unit correspond to the "first headlight" of the present invention.

  The drive circuit 43, the high beam LEDs 35 and 36, and the reflecting surfaces 15 and 16 of the reflector 1 constitute a third unit (see FIG. 2B). In response to the drive current supplied from the drive circuit 43, the high beam LEDs 35, 36 emit light. The light emitted from the high beam LED 35 is reflected by the reflecting surface 15 through the hole 17 b and is irradiated to the front of the vehicle. Further, the light emitted from the high beam LED 36 is reflected by the reflection surface 16 through the hole 17 c and is irradiated to the front of the vehicle. The reflective surfaces 15 and 16 are designed to emit light forming a high beam light distribution pattern located above the low beam low light distribution pattern. Thereby, the third unit forms a light distribution pattern of high beam. The third unit forms a light distribution pattern for illuminating the overhead sign among the low beam light distribution patterns. The third unit corresponds to the "second headlight" of the present invention.

  In the present embodiment, the reflection surfaces 11 and 12 of the reflector 1 distribute light only to a wide irradiation area of the low area in the light distribution pattern of the low beam. In addition, the reflection surfaces 13 and 14 of the reflector 1 distribute light only to the narrow illumination area of the low area in the light distribution pattern of the low beam. That is, the reflective surfaces 11 to 14, which are reflectors for low beams, do not perform light distribution for overhead, but perform light distribution for low regions of low beams. Further, in the present embodiment, the third unit forms a light distribution pattern of high beam and also forms a light distribution pattern for overhead sign. Therefore, the third unit is legally a headlamp for high beam and also a headlamp for low beam.

  The control circuit 5 is a circuit that controls the light emission of each of the LEDs 31 to 36, and is realized by each electronic component such as a microcomputer mounted on the substrate 2. The control circuit 5 controls the light emission of each of the LEDs 31 to 36 in accordance with the operation signal input from the switch 7. The switch 7 is disposed in the vehicle and operated by the driver. The switch 7 is switched by the driver when the vehicle lamp A1 is turned off, when the low beam is irradiated to the vehicle lamp A1, and when the high beam is irradiated to the vehicle lamp A1. The switch 7 outputs an operation signal corresponding to each case to the control circuit 5. The control circuit 5 switches the light emitting state (lighting or extinguishing) of each of the LEDs 31 to 36 in accordance with the operation signal input from the switch 7. The control circuit 5 also switches the brightness of the light emitted by the high beam LEDs 35 and 36 by so-called PWM dimming.

  In PWM dimming, a lighting period in which a current is supplied to an LED to light up and a switching-off period in which a current is shut off and switching off are alternately switched in a fixed short cycle, and the ratio of the lighting period in one cycle (duty ratio) Changes the brightness of the LED. By shortening the switching cycle (increasing the frequency), the human eye can not recognize flicker due to lighting and extinguishing. When the duty ratio becomes high, the lighting period becomes long, so that the light emitted from the LED becomes bright. When the duty ratio becomes low, the lighting period becomes short, so the light emitted from the LED becomes dark.

  The control circuit 5 turns off the LEDs 31 to 36 while the operation signal for turning off the vehicular lamp A1 is inputted from the switch 7. Further, while the operation signal for emitting the high beam to the vehicle lamp A1 from the switch 7 is input, the LEDs 31 to 36 are lighted with the maximum brightness. Also, while the operation signal for irradiating the low beam to the vehicle lamp A1 from the switch 7 is input, the low beam LEDs 31 to 34 are lit at the maximum brightness and the high beam LEDs 35 and 36 are decreased in brightness Turn on with. In this case, the light emitted by the high beam LEDs 35, 36 forms a light distribution pattern for illuminating the overhead sign.

  When lighting the high beam LEDs 35 and 36 with the maximum brightness, the control circuit 5 controls the duty ratio of the lighting period to be a predetermined first value (for example, 100%). When lighting is performed with the brightness reduced, the duty ratio of the lighting period is controlled to be a predetermined second value (for example, 1%). In the present embodiment, the second value is set to 0.5 to 1% of the first value. This is because the luminous intensity (maximum luminous intensity) of the light emitted by the third unit when the duty ratio is set to the first value is approximately 60000 candela, so the luminous intensity range defined by the law as the light for illuminating the overhead sign ( A maximum of 625 candela). Note that the first value and the second value are not limited, and are appropriately designed according to the standards of the high beam LEDs 35 and 36 and the light intensity of the light to be irradiated.

  As shown in FIG. 3, the control circuit 5 includes a switching unit 51, pulse generation units 52 and 53, and a duty setting unit 54 as functional blocks.

  The switching unit 51 issues commands to the pulse generation units 52 and 53 and the duty setting unit 54 in accordance with the operation signal input from the switch 7. Specifically, the switching unit 51 instructs the pulse generation units 52 and 53 not to generate pulse signals while the operation signal for turning off the vehicular lamp A1 is input from the switch 7. Further, while the operation signal for irradiating the high beam to the vehicle lamp A1 from the switch 7 is input, the duty setting unit 54 is instructed to set the duty ratio to the first value, and the pulse generation units 52 and 53 are pulsed. Command to generate a signal. While the operation signal for irradiating the low beam to the vehicle lamp A1 from the switch 7 is input, the duty setting unit 54 is instructed to set the duty ratio to the second value, and the pulse generation units 52 and 53 are pulsed. Command to generate a signal.

  The pulse generation unit 52 generates a pulse signal having a duty ratio as a first value in response to a command from the switching unit 51, and outputs the pulse signal to the drive circuits 41 and 42. The drive circuit 41 (42) to which a pulse signal having a duty ratio as a first value is input supplies a drive current corresponding to the pulse signal to the low beam LEDs 31, 32 (LEDs 33, 34). Thereby, the duty ratio of the lighting period of the low beam LEDs 31 to 34 becomes the first value, and the low beam LEDs 31 to 34 light up with the maximum brightness. On the other hand, when the pulse generation unit 52 does not generate a pulse signal, the drive circuit 41 (42) does not supply a drive current to the low beam LEDs 31, 32 (LEDs 33, 34). Therefore, the low beam LEDs 31 to 34 are turned off.

  The duty setting unit 54 sets the duty ratio in the pulse generation unit 53 in accordance with the command from the switching unit 51.

  The pulse generation unit 53 generates a pulse signal in response to the command from the switching unit 51 and outputs the pulse signal to the drive circuit 43. At this time, the pulse generation unit 53 generates a pulse signal at the duty ratio set by the duty setting unit 54. The drive circuit 43, which receives a pulse signal having a duty ratio as the first value, supplies a drive current corresponding to the pulse signal to the high beam LEDs 35 and 36. Thereby, the duty ratio of the lighting period of the high beam LEDs 35 and 36 becomes the first value, and the high beam LEDs 35 and 36 light up with the maximum brightness. Further, the drive circuit 43, to which a pulse signal whose duty ratio is the second value, is input, supplies a drive current corresponding to the pulse signal to the high beam LEDs 35 and 36. As a result, the duty ratio of the lighting period of the high beam LEDs 35 and 36 becomes the second value, and the high beam LEDs 35 and 36 light in a state where the brightness is lowered. On the other hand, when the pulse generation unit 53 does not generate a pulse signal, the drive circuit 43 does not supply the drive current to the high beam LEDs 35 and 36. Therefore, the high beam LEDs 35 and 36 are turned off.

  Next, the operation and effects of the vehicular lamp A1 according to the present embodiment will be described.

  According to the present embodiment, the control circuit 5 controls the light emission of each of the LEDs 31 to 36 in accordance with the operation signal input from the switch 7. The control circuit 5 lights each of the LEDs 31 to 36 with the maximum brightness while the operation signal for emitting the high beam is input from the switch 7. Therefore, all of the first to third units emit light of maximum brightness. As a result, the first unit and the second unit form a low beam light distribution pattern of the low beam, and the third unit forms a light distribution pattern of the high beam. Further, while the operation signal for irradiating the low beam is inputted from the switch 7, the control circuit 5 lights the low beam LEDs 31 to 34 with the maximum brightness and lights the high beam LEDs 35, 36 in the state of decreasing the brightness. Let Thus, the first unit and the second unit emit light of maximum brightness and the third unit emits light of reduced brightness. As a result, the first unit and the second unit form a low beam light distribution pattern of the low beam, and the third unit forms a light distribution pattern for illuminating the overhead sign.

  That is, at the time of low beam irradiation, the vehicle lamp A1 irradiates the light whose brightness is reduced from the third unit, and uses this light for light distribution for the overhead sign. Since the light distribution for the overhead sign is light whose brightness is lowered, it is possible to suppress the driver of the oncoming vehicle from feeling glare. Further, since the light distribution for the overhead sign is irradiated from the third unit, the light of the first unit and the second unit for forming the low-beam light distribution pattern of the low beam is not reduced.

  In the case of the conventional system in which light reflected by a part of the reflecting surface of the reflector is used for light distribution for overhead sign, the headlight for high beam irradiation is turned off at the time of low beam irradiation. In this case, when viewed from the front of the vehicle, part of the outer lens of the vehicle lamp becomes dark. On the other hand, in the case of the vehicle lamp A1, the third unit (headlight for high beam irradiation) emits light, although the brightness is lowered even at the time of low beam irradiation. Therefore, when viewed from the front of the vehicle, the entire outer lens of the vehicle lamp A1 looks bright, so that the design of the appearance can be improved.

  In the present embodiment, when the high beam is irradiated, the case where the low beam is also irradiated is described, but the present invention is not limited to this. When the high beam is irradiated, the low beam may not be irradiated. Specifically, the control circuit 5 may turn off the LEDs 31 to 34 while an operation signal for emitting a high beam is input from the switch 7.

  In the present embodiment, the control circuit 5 switches the brightness of the light emitted from the high beam LEDs 35 and 36 by PWM dimming, but the present invention is not limited to this. The control circuit 5 may switch the brightness of the light emitted from the high beam LEDs 35 and 36 by changing the magnitude of the current flowing through the high beam LEDs 35 and 36 to the drive circuit 43.

  In the present embodiment, an LED is used as a light source, but the present invention is not limited to this. The light source may be, for example, a halogen bulb. However, since at least the light source for high beam must be switchable in brightness, it is necessary to be able to control the brightness when using another light source. Therefore, as a light source for high beam, it is desirable to use an LED whose brightness can be easily controlled. On the other hand, since the light source for low beam does not need to switch the brightness, a light source other than the LED may be used.

  Although the case where the irradiation state of the vehicle lamp A1 is switched by the switch 7 has been described in the present embodiment, the present invention is not limited thereto. The lighting and extinguishing of the vehicular lamp A1 may be automatically switched depending on the outside brightness. In addition, it is possible to automatically switch between the high beam and the low beam by identifying an oncoming vehicle or a vehicle traveling in the front based on an image obtained by photographing the front.

  In addition, the shape of the reflector 1, the number of reflective surfaces, and arrangement | positioning are not limited. For example, the LEDs 31, 33, 35 are low beam LEDs, and the LEDs 32, 34, 36 are high beam LEDs. The upper reflecting surfaces 11, 13, 15 of the reflector 1 emit low beams, and the lower reflecting surfaces 12, 14, 16 May emit a high beam. Also, as shown in FIG. 4A, the reflector 1 has only the reflecting surfaces 12, 14 and 16 (without the reflecting surfaces 11, 13 and 15), and the low beam LEDs 32 and 34 and the high beam LED 36 as shown in FIG. (Without the low beam LEDs 31, 33 and the high beam LED 35). Further, as shown in FIG. 4B, the reflector 1 has only the reflection surfaces 11, 12, 15, 16 (without the reflection surfaces 13, 14) as in the vehicle lamp A3 shown in FIG. , 36 (without the low beam LEDs 33, 34). In this case, the reflecting surfaces 11 and 12 are designed so that light can be irradiated to both a wide irradiation area and a narrow area of the low beam low area light distribution pattern. In addition, the reflector 1 may not be integrated but a reflector for each reflection surface may be provided.

  The vehicular lamp according to the present invention is not limited to the embodiment described above. The specific configuration of each part of the vehicle lamp according to the present invention can be varied in design in many ways.

A1, A2 and A3: Vehicle lamps 1: Reflectors 11 to 14: Reflective surfaces 15 and 16: Reflective surface 17: Projections 17a: Spaces 17b and 17c: Holes 2: Substrate 2a: Upper surface 2b: Lower surfaces 31 to 34: Low beam LED
35, 36: High beam LED
41 to 43: drive circuit 5: control circuit 51: switching units 52 to 53: pulse generation unit 54: duty setting unit 7: switch

Claims (1)

With the first headlight,
A second headlight that emits light above the first headlight;
A control circuit that switches between a state in which light distribution for high beam is performed and a state in which light distribution for low beam is performed;
Equipped with
The control circuit causes the first headlight to emit light and lowers the brightness of the second headlight when the low beam light distribution is to be performed. Make the irradiation of
A vehicle lamp characterized in that.

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