JPH0731446Y2 - Car headlamp - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a headlamp using a discharge bulb as a light source, and in particular, by moving a forming shade to a sub-beam, a reflector from a discharge part which is a light emitting source. The present invention relates to an improvement of Japanese Patent Application No. 1-127877, which is a headlamp for an automobile, in which both a main beam and a sub beam can be formed by cutting off a part of the light directed to.

[Problems to be Solved by Prior Art and Invention]

As a conventional automobile headlamp, a bulb-type bulb is generally used. For example, an H ₄ bulb in which two filaments are arranged in parallel in the optical axis direction in a glass sphere, A main beam and a sub-beam are formed by switching the power supply to each filament.

However, since the filament, which is a light emitting source, and the filament supporting portion are heated to a high temperature, the filament may be broken due to long-term use, and there is a problem in durability. In addition, conventional bulbs use electric energy to heat a filament to emit light and utilize the light emitted by this filament. Most of the electric energy is radiated as heat energy, and only part of the heat energy is converted to light energy. Therefore, there is a problem that the energy efficiency is very poor and the power consumption is accordingly increased.

In view of the above-mentioned problems of the prior art, the discharge bulb of the type that emits light by the discharge between the electrodes has no problem of disconnection like the type that emits the filament described above, and the power consumption is higher than that of the filament type. In view of its small size and large light quantity, a discharge bulb has recently been attracting attention as a headlamp bulb. However, there is a problem in that two light emitting parts of the discharge bulb cannot be provided like the filament of the H ₄ type bulb, and two different light distributions of the main beam and the sub beam cannot be formed by one discharge bulb.

Therefore, Japanese Patent Application No. 1-127877 has been proposed as a prior art for solving these problems. In this prior art, a shade member that is movable back and forth in the optical axis direction is provided in the headlamp, and the shade member is moved rearward in the optical axis direction to block a part of the light traveling from the discharge part of the discharge bulb to the reflector. Form the sub beam, on the contrary, move the shade member forward in the optical axis direction to form the main beam without blocking the light going from the discharge part of the discharge bulb to the reflector,
One discharge bulb enables two different light distributions of the main beam and the sub beam. In addition, in this proposal, since a discharge bulb that has a larger amount of light than the H ₄ type bulb is used, there is a tendency for the area where the illuminance is too high to occur in the light distribution pattern of the main beam, but the shape of the shade member The light from the discharge part of the discharge bulb to the reflector is partially blocked even when the main beam is being formed, and the main beam, which tends to be too bright at a certain part, is partially dimmed to distribute the main beam. A means for appropriately adjusting the illuminance of the light pattern is disclosed.

However, since the shade member has a shape that emphasizes the original purpose of forming the sub beam, it is not easy to make the shape that also satisfies the appropriate illuminance of the main beam.

The present invention has been made in view of the above problems, and an object thereof is to use a discharge bulb as a bulb of an automobile headlamp and to enable two light distributions of a main beam and a sub beam by one discharge bulb. An object of the present invention is to provide an automobile headlamp that can obtain a main beam having a light distribution pattern with various illuminances.

[Means for Solving the Problems]

In order to achieve the above object, in an automobile headlamp according to the present invention, a parabolic reflector is provided in a lamp body, and a discharge bulb having a discharge part, which is a light emitting source, near a focal point of the reflector. A shade member movable in the optical axis direction of the reflector in the vicinity of the discharge part is provided, and when the shade member moves rearward, a part of the light traveling from the discharge part of the discharge bulb toward the reflector is shaded. When the sub-beam is formed by being blocked by the shade member and the shade member is moved forward, the light heading from the discharge part of the discharge bulb toward the reflector is not blocked by the shade member to form the main beam. Is provided with a movable reflector that moves integrally with the shade member, and in claim (1), the reflector. A non-reflecting surface area is formed in a predetermined area of the effective reflecting surface, and the movable reflector is located in front of the non-reflecting surface area of the reflector when the shade member moves backward, and functions as an effective reflecting surface in place of the non-reflecting surface. According to the present invention, the movable reflector is positioned on the front surface of the reflector when the shade member moves rearward, and functions similarly to the effective reflection surface of the reflector, and the reflector moves when the shade member moves forward. It is configured so that the reflected light in a predetermined area of the effective reflection surface of is blocked.

[Action]

The discharge bulb is a structure that emits light by the discharge between the electrodes,
There is no risk of disconnection. Further, since the electrons are directly converted into light energy, the efficiency of energy conversion from electric energy to light energy is high, and therefore power consumption is low.

In claim (1), when the movable reflector is moved backward together with the shade member, the shade member is located between the discharge part and the reflector, and the movable reflector is located in front of the non-reflection surface region of the reflector. At this time, the shade member blocks a part of the light traveling from the discharge part to the reflector, and the light left unblocked is reflected by the reflector and the movable reflector to form a sub-beam. When the movable reflector is moved forward together with the shade member, the shade member is not located between the discharge part and the reflector, and the movable reflector is not located in front of the non-reflecting surface area of the reflector. At this time, the shade member does not block the light traveling from the discharge part to the reflector, reflects the light from the discharge part in the part excluding the non-reflective surface area of the reflector, and distributes light equivalent to the reflected light in the non-reflective surface area. A reduced main beam is formed.

In claim (2), when the movable reflector is moved backward together with the shade member, the shade member is located between the discharge part and the reflector, and the movable reflector is located in front of the reflector. At this time, the shade member blocks a part of the light traveling from the discharge part to the reflector, and the light left unblocked is reflected by the reflector and the movable reflector to form a sub-beam. Then, when the movable reflector is moved forward together with the shade member, the shade member is not positioned between the discharge part and the reflector, but the movable reflector is positioned in front of a predetermined area of the reflector. At this time, since the shade member does not block the light traveling from the discharge part to the reflector, the reflector reflects the light from the discharge part. However, since the movable reflector is located on the optical path of the reflected light in the predetermined area of the reflector and the reflected light is blocked by the movable reflector, the main beam in which the light distribution equivalent to the reflected light in the predetermined area is reduced is formed. .

〔Example〕

 Next, an embodiment of the present invention will be described with reference to the drawings.

1 to 3 show a headlamp according to a first embodiment of the present invention. FIG. 1 is a perspective view of the headlamp with a lens removed, and FIG. 2 shows a shade member and a shade member. FIG. 3 is a perspective view of an integrated movable reflector and a recess formed in the reflector, and FIG. 3 is a vertical cross-sectional view of the headlamp.

In these drawings, reference numeral 10 is a container-shaped lamp body that opens forward, and a lens 11 is provided at the front opening of the lamp body 10. The lamp body 10 is fixed to a vehicle body (not shown), and the inner peripheral surface of the lamp body 10 is vapor-deposited with aluminum to integrally form a reflector 12. A bulb insertion hole 14 is formed in the rear top portion of the lamp body 10, and a discharge bulb 20 that emits light due to discharge between the electrodes is inserted therein. Reference numeral 21 indicates a discharging unit. The reflector 12 is composed of a ceiling area 12C and a lower surface area 12D each having a planar shape, and a reflector upper side 12A and a lower side 12B each having a parabolic shape, and the focal points of the reflector upper side 12A and the lower side 12B are the discharge portion. 2
It is almost the same as position 1. That is, the light emitted from the discharge part 21 is reflected by the reflector 12 to be made into substantially parallel light and enters the lens 11, and is diffused in a predetermined forward direction by a diffusion step (not shown) formed on the back surface of the lens 11. The beam of the headlamp is designed to be distributed. Note that reference numeral 1 is an irradiation axis (optical axis) of the headlamp. The reflector upper side 12A and the lower side 12B are effective reflecting surfaces that mainly contribute to the formation of the headlamp beam, and if only the reflected light of the reflector upper side 12A, the sub beam (beam for passing) is reflected on the reflector upper side 12A and the lower side. The main beam (traveling beam) is formed if the light is reflected from both sides 12B. Further, reference numeral 12a is a predetermined region substantially in the center of the reflector upper side 12A, and the predetermined region 12a is a region mainly contributing to the light distribution of a portion where the illuminance is too high in the light distribution pattern of the main beam. Then, in the predetermined region 12a, a recess 12E which is a non-reflective surface region where aluminum vapor deposition processing is not performed is formed.

Reference numeral 30 is a shade member shaped like a semi-cylindrical part of a thin cylinder cut out, and has a long semi-cylindrical lower region 30.
It consists of a and a short semi-cylindrical upper region 30b. Code 40
Is a movable reflector with a thin parabolic shape.
Only aluminum is vapor-deposited to be a light reflecting surface, and the rear surface 40b is a light non-reflecting surface. The shade member 30 and the movable reflector 40 are integrated into a shade 50 with a reflector via the connecting members 41, 41 (see FIG. 2). A plate-shaped leg is provided at the bottom of the shade 50 with reflector.
31 is provided, a long hole 13 is formed on the lower surface of the lamp body 10, and the leg portion 31 extends through the long hole 13 to the outside of the lamp body 10 and is provided on the vehicle body (not shown) side. It is supported by the unit 36. Inside the moving unit 36, a moving mechanism using an electromagnetic valve or a motor electrically controlled by a switch (not shown) as a driving means is provided.
The leg 31 can be moved back and forth in the optical axis 1 direction. That is, the shade 50 with a reflector integrated with the leg 31 is
It moves back and forth in the direction of the optical axis l and moves to the front position (the position where the shade 30 is separated from the front of the discharge bulb 20) and the rear position (the shade).
The position where 30 covers the discharge bulb 20) can be selected alternatively. Then, when the shade with reflector 50 takes the rearward position, the movable reflector 40 is fitted into the recess 12E of the reflector upper side 12A, and the movable reflector front
The surfaces of 40a and the reflector upper side 12A are flush with each other, and at this time, the focal point and the optical axis of the movable reflector front surface 40a are made to coincide with the focal point and the optical axis of the reflector upper side 12A.

That is, as shown by the solid line in FIG. 3, when the shade with reflector 50 is set to the rear position, the movable reflector 40 is fitted into the recess 12E of the reflector upper side 12A, and the shade member 30 is in a position to cover the discharge bulb 20. Valve discharge part 21
Block the light from the area except the upper side of the reflector.
That is, the reflector lower side 12B, the ceiling area 12C, the lower surface area 12
The shade member 30 blocks light directed to D. Therefore, the light emitted from the bulb discharger 21 is reflected by the reflector upper side 12A and the movable reflector front surface 40a to form a sub beam.

Then, as shown by the phantom line in FIG. 3, when the shade with reflector 50 is moved to the front position, the movable reflector 40 is moved.
Is located far away from the front side of the reflector.
The recess 12E of 12A is exposed, and the shade member 30 is the discharge bulb 20.
Does not block the light from the bulb discharge part 21 toward the reflector. That is, the light emitted from the bulb discharge part 21 is reflected by the reflector upper side 12A, the reflector lower side 12B, the reflector ceiling area 12C, and the lower surface area 12C to form a main beam, but the concave portion 12E of the reflector upper side 12A.
Light is not reflected in the predetermined region 12a in which is formed. That is, in the light distribution pattern of the main beam, the light distribution to the part where the illuminance is too high is reduced, and the illuminance at this part is set to an appropriate value, whereby a main beam having a light distribution pattern of the appropriate illuminance is obtained. ing. In addition, the front position of the movable reflector 40 at this time is a front position away from the recessed portion 12E, and is a place where the reflected light on the effective reflection surface of the reflector 12 does not come to the rear surface 40b, so that the movable reflector 40 is It does not hinder the light distribution of the main beam.

Further, in the modified example of the first embodiment, it is also possible to configure the predetermined region 12a of the reflector upper side 12A as a non-reflective surface that is not simply subjected to aluminum vapor deposition and not to form the recess 12E. In this case, when the shade 50 with a reflector is set to the rear position, the movable reflector 40 is placed above the reflector 12
If the focal point and the optical axis of the movable reflector front surface 40a coincide with the focal point and the optical axis of the reflector upper side 12A, the same effect as that of the first embodiment can be obtained.

Next, a second embodiment of the present invention is shown in FIG. This second
The embodiment is different from the first embodiment only in the following points, and is otherwise configured similarly. That is, the recess 12E is not formed in the predetermined area 12a of the reflector upper side 12A, and it is made an effective reflection surface as it is. At this time, the focus and the optical axis of the movable reflector 40 are made to coincide with the focus and the optical axis of the reflector upper side 12A. And
When the shade with reflector 50 takes the front position,
The movable reflector 40 is a predetermined area 1 on the upper side 12A of the reflector.
It is located in front of 2a and is in a state of just blocking the reflected light traveling forward from the predetermined area 12a.

That is, as shown by the solid line in FIG. 4, when the shade 50 with a reflector is set to the rear position, the movable reflector 40 comes close to the reflector upper side 12A, and the shade member 30 comes to a position to cover the discharge bulb 20. Block the light from the area except the upper side of the reflector. That is, the shade member 30 blocks the light traveling toward the reflector lower side 12B, the ceiling area 12C, and the lower surface area 12D. Therefore, the light emitted from the bulb discharger 21 is reflected by the reflector upper side 12A and the movable reflector front surface 40a to form a sub beam.

Then, as shown by the phantom line in FIG. 4, when the shade 50 with a reflector is moved to the front position, the movable reflector 40 is moved.
Is a position far away from the predetermined region 12a,
The shade member 30 does not cover the discharge bulb 20 and does not block the light from the bulb discharge portion 21 toward the reflector. The bulb discharge part 21 emits light from the reflector upper side 12A, the reflector lower side 12B, the reflector ceiling region 12C,
Although reflected by the lower surface area 12C, only the light reflected by the predetermined area 12a of the reflector upper side 12A is blocked by the movable reflector rear surface 40b. That is, in the light distribution pattern of the main beam, the light distribution to the part where the illuminance is too high is reduced, and the illuminance at this part is set to an appropriate value, whereby the main beam having the light distribution pattern of the appropriate illuminance is obtained. There is.

Further, as a modification of the second embodiment, it is possible to adopt a configuration in which the rear surface 40b of the movable reflector is also subjected to aluminum vapor deposition to be used as a light reflecting surface. In this case, when the shade with reflector 50 is set to the rear position, a sub beam is formed as in the second embodiment. When the shade 50 with a reflector is set to the front position, the light distribution to a portion where the illuminance is too high in the light distribution pattern when the main beam is formed is reduced in the same manner as in the second embodiment. Is added. That is, the light blocked by the rear surface 40b of the movable reflector is rearward at the rear surface 40b (effective reflection surface side of the reflector 12).
The reflected light is diffused and directed toward the reflector upper side 12A, is reflected again by the reflector upper side 12A, and finally contributes to the formation of the main beam. In other words, in this case, the light distribution to the area where the illuminance is too high on the light distribution pattern of the main beam is reduced, but the reduced light distribution is distributed to other areas where high illuminance is required, Further, it is considered as a main beam having a light distribution pattern with appropriate illuminance.

In addition, in the above various embodiments (and modified examples),
When the shade with reflector 50 is in the front position (main beam forming position), a part of the light traveling from the bulb discharge part 21 to the reflector ceiling region 12C is movable as shown by an arrow m in FIGS. 3, 4, and 5. The light is reflected by the front surface 40a of the reflector, is redirected obliquely upward to the front, is reflected by the reflector ceiling region 12C, and is further partially reflected by the lower face region 12D, and finally is emitted from the lens 11. This light is unnecessary for forming the light distribution pattern of the lamp, but it is not the main light distribution that forms the main beam,
It can be ignored due to the light distribution of the main beam. Also, the shade member
The area of the 30, the connecting members 41, 41 and the leg portion 31 viewed from the direction of the optical axis 1 is made as small as possible so that the effective reflected light from the reflector 12 that contributes to the light distribution is not blocked.

[Effect of device]

As is clear from the above description, according to the vehicle headlamp according to the present invention, since the discharge bulb used as the light source has no risk of disconnection, a vehicle headlamp which does not require bulb replacement for a long period of time can be obtained. . Moreover, since the discharge bulb has a high conversion efficiency of electric energy to light energy, it consumes less power.

Also, by moving the shade member back and forth in the direction of the optical axis and changing its position, it is possible to obtain light distributions for both the sub-beam and the main beam, so that one discharge valve can be used to provide the main beam and the sub-beam. Different light distributions are realized.

Further, in the light distribution to a portion of the main beam light distribution pattern where the illuminance is too high, in claim (1), the light distribution equivalent to the reflected light in the non-reflecting surface area is reduced to obtain an appropriate illuminance. The main beam of the light distribution pattern is obtained, and in claim (2), the movable reflector shields the reflected light in the predetermined area of the reflector, and the light distribution equivalent to the reflected light in the predetermined area is reduced to obtain an appropriate illuminance. The main beam of the light distribution pattern is obtained.

[Brief description of drawings]

FIG. 1 is a perspective view of a headlamp of a first embodiment of the present invention with a lens removed, FIG. 2 is a perspective view of a shade member and a movable reflector of the same embodiment, and FIG. 3 is a perspective view of the same embodiment. It is a longitudinal cross-sectional view of a headlamp. FIG. 4 is a vertical sectional view of a headlamp according to a second embodiment of the present invention. 10 …… Lamp body, 12 …… Reflector, 12A …… Reflector upper side which is an effective reflection surface, 12B …… Reflector lower side which is an effective reflection surface, 12a …… Predetermined area of the effective reflection surface of the reflector, 12E …… Predetermined A concave portion which is a non-reflective surface area formed in the area, 20 ... Discharge bulb, 21 ... Discharge section which is a light emitting source, 30 ... Shade member, 40 ... Movable reflector, 40a ... Front of movable reflector, 40b …… The rear surface of the movable reflector.

Claims (2)

[Scope of utility model registration request] 1. A parabolic reflector in a lamp body, a discharge bulb in which a discharge part, which is a light emitting source, is located near a focal point of the reflector, and in the vicinity of the discharge part, in front of and behind the optical axis of the reflector. A movable shade member is provided, and when the shade member moves rearward, a part of light traveling from the discharge part of the discharge bulb toward the reflector is blocked by the shade member to form a sub-beam, and the shade member moves forward. Is a headlamp for an automobile, in which light traveling from the discharge part of the discharge bulb toward the reflector is not blocked by a shade member to form a main beam when moved to a predetermined area of the effective reflection surface of the reflector. A surface area is formed, and a movable reflector that moves integrally with the shade member is formed on the shade member. Vignetting,
The movable reflector is located in front of the non-reflective surface region of the reflector when the shade member moves rearward, and functions as an effective reflective surface in place of the non-reflective surface. 2. A paraboloidal reflector in a lamp body, a discharge bulb having a discharge part, which is a light emitting source, in the vicinity of the focal point of the reflector, and in the vicinity of the discharge part in the front-back direction in the optical axis direction of the reflector. A movable shade member is provided, and when the shade member moves rearward, a part of light traveling from the discharge part of the discharge bulb toward the reflector is blocked by the shade member to form a sub-beam, and the shade member moves forward. Is a headlamp for an automobile, in which light traveling from the discharge part of the discharge bulb to the reflector is not blocked by a shade member to form a main beam, when moving to the shade member, the shade member moves integrally with the shade member. A movable reflector is provided, and this movable reflector is
When the shade member moves rearward, it is positioned in front of the reflector and functions in the same manner as the effective reflection surface of the reflector, and when the shade member moves forward, it blocks reflected light in a predetermined area of the effective reflection surface of the reflector. Headlamps for automobiles.