JP2001312906A - Headlamp for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem of a poor luminous flux utilization factor with respect to a light source and low efficiency in a headlamp for a vehicle of a conventional construction, because of shading about half of the volume of light by a hood or a shade plate for forming a luminous intensity distribution characteristics. SOLUTION: In a headlamp for a vehicle 1, a light source 2 is surrounded by plural ellipse-type light concentrating reflectors 3 over almost the whole periphery and light is projected on the light concentrating reflectors 3 is an irradiation direction by a parabola-type irradiation reflector 4, having a focus at a location of a second focus. Almost whole volume of light from the light source 2 is utilized as irradiation light, and efficiency is improved exceptionally.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular lamp, and more particularly to a vehicular lamp for lighting such as a headlamp and a fog lamp. The purpose of the present invention is to provide means for solving the problems that have occurred in the above.

[0002]

2. Description of the Related Art FIGS. 6 and 7 show an example of the structure of a conventional vehicle lamp for lighting.
The vehicle lighting device 90 shown in FIG. 1 includes a light source 91 such as a filament of an incandescent lamp, a parabolic reflecting surface 92 such as a paraboloid of revolution having a focus at a position appropriately behind the light source 91, and a reflecting surface 92. And a lens 93 that covers the front and is provided with a diffusion prism cut 93a.

[0003] With this configuration, the reflection surface 9
2, the light of the light source 91 reflected on the upper half is directed downward, and the light of the light source 91 reflected on the lower half is directed upward, so that the light source 91 includes a hood 91 for shielding the lower half.
a is provided, and a passing light distribution is formed so as not to generate upward light.

A vehicular lamp 80 shown in FIG. 7 includes a light source 81, an elliptical reflecting surface 82 such as a spheroid having a first focal point on the light source 81, and a position of a second focal point of the reflecting surface 82. A projection lens 83 that projects a cross-sectional shape of a light beam converging on the projection direction in the irradiation direction, and a substantially lower half portion that becomes upward light after being projected by the projection lens 83 from the light beam converging on the second focal point And a shielding plate 84 for shielding the light.

With this configuration, the projection lens 8
3 reverses the cross-sectional shape of the substantially crescent half-moon luminous flux by the shielding plate 84, and projects the half-moon shape of the upper chord in the irradiation direction, and includes upward light similarly to the vehicle lamp 90. No passing light distribution is formed.

In actual practice, in order to facilitate confirmation of a pedestrian on the roadside or a road sign provided on the roadside, an appropriate upward light is applied to the left side in the case of left-hand traffic. The shape of the hood 91a and the shape of the shielding plate 84 are appropriately changed so as to radiate.
In the vehicular lamp 90, a traveling light source 94 without a hood is provided behind the light source 91, and by switching to the traveling light source 94, a traveling light distribution is obtained. .

[0007]

However, in the above-described conventional configuration, in the vehicular lamp 80, a shielding plate 84 for shielding about half of the light amount is necessary for forming the passing light distribution. Since the hood 91a that shields about half of the light is similarly required in the lighting device 90, the luminous flux utilization rate for the light sources 81 and 91 is low, and the light source 8
However, there is a problem that the light amount is dark for the light amount of 1,91.

Although the vehicle design is basically required to be wide and low, the vehicle lamp 80 can be set at a low height, but cannot be realized widely. It is possible, and when the height is set low in the vehicular lamp 90, the luminous flux capturing rate is further reduced and it is not feasible, so that the current design cannot be largely changed in any case. However, this has caused a problem that the design has become obsolete.

[0009]

According to the present invention, as a specific means for solving the above-mentioned conventional problems, a light source having a major axis having an angle of 45 to 135 degrees with the central axis of the light source is provided as a first light source. At least one pair of light-collecting reflecting surfaces each of which is provided as a focal point so as to substantially surround the light source and is symmetrically disposed with respect to a vertical line passing through the light source, and each of the light-collecting reflecting surfaces; A parabolic system having a focal point at a position substantially coinciding with the second focal point of the reflecting surface and having an axis substantially coincident with the irradiation direction of the vehicle headlamp is disposed substantially linearly in the same number as the condensing reflecting surface. And a reflecting plate for giving a shape of light distribution characteristics to the condensing reflection surface in the vicinity of the second focal point of each of the condensing reflection surfaces. It solves the problem by providing a featured vehicle headlamp. That.

[0010]

Next, the present invention will be described in detail based on an embodiment shown in the drawings. 1 and FIG.
Is a vehicle headlight according to the present invention, and the figure is shown in a simplified and schematic state for easy understanding. As the light source 2 of the vehicular headlamp 1, any type such as a halogen lamp or a metal halide discharge lamp can be adopted, but in the case of a halogen lamp, a single filament without a hood is provided. In the case of a metal halide discharge lamp, it is preferable to use a D2S type having no black stripe.

Further, the present invention can be applied to an elliptical reflecting surface such as a spheroid which surrounds the light source 2 substantially all around and has a major axis Y substantially perpendicular to the central axis X of the light source 2. In order to facilitate understanding, here, the first focus f1
At least one pair of the light-collecting reflecting surfaces 3 is disposed so as to substantially match the position of the light source. In this embodiment, a pair of the first condensing reflection surfaces 31L and 31R and the second condensing reflection surface 32
Although an example in which one pair of L and 32R and two pairs of convenience are arranged will be described, the present invention is not limited to this number. In the present invention, the angle of the major axis Y with respect to the central axis X is 45 to 135.
The present invention can be applied to the angle of the angle of 90 degrees.

In the present invention, the first condensing reflection surface 3 is used.
1L and the second light-condensing reflection surface 32L, the first light-condensing reflection surface 31R and the second light-condensing reflection surface 32R form a straight line Z orthogonal to the center line X and the long axis Y of the light source 2. Are arranged so as to be line-symmetric with respect to. By doing in this way, almost all of the light emitted from the light source 2 is reflected by the light-collecting reflection surface 3, that is, the first light-collection reflection surface 31 (L, R) and the second light-collection reflection surface 32 ( L, R).

As described above, since both the first light-collecting reflecting surface 31 and the second light-collecting reflecting surface 32 are elliptical, the light from the light source 2 that has been captured is converted into the respective second focal points f2.
And the respective second focal points f2
In response to this, a reflecting surface 4 for parabola such as a paraboloid of revolution having the second focal point f2 as a focal point and having an axis substantially parallel to the central axis X of the light source 2 is provided for each.

Therefore, the light-collecting reflecting surface 3 is composed of the first light-collecting reflecting surface 31 (L, R) and the second light-collecting reflecting surface 32 (L, R).
In the case of two pairs, the irradiation reflecting surface 4 is also the first irradiation reflecting surface 41 (L, R) and the second irradiation reflecting surface 42 (L, R).
R), and almost all of the light of the light source 2 captured by the light-collecting reflecting surface 3 is used as irradiation light.

It is to be noted that, for example, two pairs of the light-collecting reflecting surface 3 and the irradiation reflecting surface 4 can be arranged in any manner. As described above, two pairs (four surfaces) of the irradiation reflecting surfaces 4 are arranged in one horizontal line, and accordingly, the distance between the focal points f1 and f2 of the light collecting reflecting surface 3 is also changed to the first light collecting reflecting surface. 31 (L,
R) and the second condensing reflection surface 32 (L, R).

The above is the basic structure of the vehicle headlamp 1 of the present invention. In the above-mentioned state, the light captured by the light-collecting reflection surface 3 is simply converted into substantially parallel light by the irradiation reflection surface 4 in the irradiation direction. Since the light is merely directed, it is not possible to freely form a desired light distribution shape such as passing light distribution.

Therefore, in the present invention, in addition to the above configuration,
A shielding plate 5 is provided in the vicinity of the second focal point f2 of each of the condensing reflection surfaces 3, and a cross section of the reflected light from the condensing reflection surface 3 converged on the second focal point f2 by the shielding plate 5. The shape when the shape is adjusted and the light is reflected in the irradiation direction by the irradiation reflecting surface 4 is suitable for a desired light distribution shape such as, for example, passing light distribution.

Therefore, the function of the shielding plate 5 is almost the same as that of the hood or the shielding plate described in the conventional example, but the shielding plate of the conventional example is mounted in a state substantially perpendicular to the long axis of the reflecting surface. In contrast, in the present invention, the state is set to be nearly parallel to the long axis Y in the present invention (see FIG. 7). Further, the shielding plate 5 may be provided for each of the condensing reflection surfaces, for example, the first condensing reflection surface 31L and the second condensing reflection surface 32L. Since the second focal points f2 are close to each other, they are integrally formed in the present invention.

If a reflecting film is formed by vacuum evaporation of aluminum near the front end of the surface facing the condensing reflection surface, for example, the condensing reflection surfaces 31L and 32L, the shielding plate 5 The light that has been shielded by is reflected by the reflection film and travels toward the irradiation reflecting surface 42L, that is, is collected as irradiation light of the vehicle headlamp 1.

The operation and effects of the vehicle headlamp 1 of the present invention having the above-described structure will be described. First, according to the present invention, since almost the entire circumference of the light source 2 is surrounded by the reflecting surface 3 for condensing, the light beam capturing rate for the light source 2 is improved to about 60%, which is about twice as large as that of the conventional example. Thus, even with the same light source 2, it is possible to realize a headlight that is significantly brighter and has excellent visibility.

Further, since the reflecting surface 4 for irradiation has the structure of the present invention, it is divided into four parts in this embodiment. Therefore, if the area viewed from the front is the same,
It becomes possible to make the depth dimension much smaller. Also,
The fact that the irradiation reflecting surfaces 4 are divided means that the vehicle headlamp 1 having an unusually wide width and a narrow height direction can be realized by means such as arranging them in one horizontal row. It is possible to match the entire design without loss of light quantity.

Further, since the light is incident on each irradiation reflection surface 4 in an optimal shape by a shielding plate 5 provided at the position of the second focal point f2 of each light collection reflection surface 3, the light source 2 Therefore, it is not necessary to provide a hood, a black stripe, or the like for forming a light distribution, and in this respect, the luminous flux utilization rate is improved and a bright vehicle headlamp 1 can be realized.

FIGS. 3 to 5 show another embodiment of the present invention. In the previous embodiment, the obtained light distribution characteristics, such as passing light distribution, are limited. However, when a metal halide discharge lamp is used as the light source 2, the metal halide discharge lamp requires an activation device and the like, and is expensive. When the light source is provided, the cost is further remarkably increased. Therefore, a headlight capable of switching the light distribution characteristics with one light source is demanded.

This embodiment has been made in order to meet the above-mentioned demands. As a specific means, in this embodiment, the shielding plate is made movable to form a movable shielding plate 6. At the same time, as shown in FIG.
A shielding portion 6a corresponding to the first irradiation reflecting surface 41L;
The shielding portion 6b corresponding to the second irradiation reflection surface 42L on the same side is integrated, and both are movable in a seesaw shape by a rotation shaft 6c provided substantially at the center of each of the shielding portions 6a and 6b. .

FIG. 5 is a diagram for explaining the operation state of the movable shielding plate 6. First, when a passing light distribution is generated between the first irradiation reflecting surface 41L and the second irradiation reflecting surface 42L, FIG. It is set to the state shown by the solid line. Then, the shielding portion 6a completely shields the light from the first condensing reflection surface 31L incident on the first irradiation reflecting surface 41L, and the shielding portion 6b is in the light beam from the second condensing reflection surface 32L. A part of the light is inserted into the upper part to block the part that becomes the upward light.

Therefore, in this state, in the vehicle headlamp 1 according to this embodiment, no light is emitted from the first irradiation reflecting surface 41L, and the second irradiation reflecting surface 42L is not emitted.
, The downward light is radiated only from the light source, so that the passing light distribution can be obtained. In the above description, the shielding portion 6b shields a part of the second condensing reflection surface 32L at the time of generating the passing light distribution, so that the reflection film 6d is formed near the shielding portion 6b (see FIG. 4), the light that has been shielded in the same manner as described above can be reflected and collected on the second irradiation reflecting surface 42L.

When generating the traveling light distribution, the rotating shaft 6c is rotated clockwise by an appropriate amount in the state shown in the figure. Then, the movable shielding plate 6 is set to a state shown by a chain line in FIG. 5, and the shielding portion 6a retreats from the light beam from the first condensing reflection surface 31L, and transmits light to the first irradiation reflection surface 41L. give. At the same time, the shielding portion 6b completely retreats from the light beam from the second light-collecting reflection surface 32L.

Therefore, both the irradiation light from the first irradiation reflection surface 41L and the irradiation light from the second irradiation reflection surface 42L include upward light, so that a traveling light distribution for irradiating a distant front of the vehicle can be obtained. It becomes what is done. In this embodiment, the left half of the vehicle headlamp 1, that is, the first irradiation reflecting surface 41.
L, movable shielding plate 6 only for second irradiation reflecting surface 42L
However, in this case, the right half may be configured to always form a passing light distribution.

Although not shown, the right half, ie, the first irradiation reflecting surface 31R, the second irradiation reflecting surface 32R
May be provided with a similar movable shielding plate 6. In this case, one driving unit may be used to provide both movable shielding plates 6.
Can also be driven. In consideration of the above configuration, it is expected that the shielding portion 6a and the shielding portion 6b are movable, and the amount of movement required to switch the light distribution characteristics is expected to be different. By appropriately setting the positions, it is possible to give a necessary movement amount to each.

In addition, in the above embodiment, when the passing light distribution is obtained, the side of the first irradiation reflecting surface 41L does not emit light, but this is because the second irradiation reflecting surface 42L side emits light. Irradiation may not be performed, and the irradiation reflecting surfaces that do not emit light may be switched between the right side and the left side, and any combination of the above-described means is possible.

In the above, in order to simplify the explanation,
The description has been made assuming that the light source has the major axis Y substantially perpendicular to the central axis X of the light source. However, as described above, this can correspond to an angle of 45 to 135 degrees. Furthermore, in the present invention, the first irradiation reflecting surface and the second irradiation reflecting surface are described as being arranged at right angles to the traveling direction of the vehicle, but the present invention is not limited to this. is not.

In an actual vehicle, the vehicle body is sometimes referred to as a streamline type or the like, and the corners may be inclined up to approximately 45 degrees in the front-rear and vertical directions. Also, it was common sense to install headlights with the longitudinal direction being horizontal, but in recent vehicle designs, the longitudinal direction has to be installed, for example, as a hanging eye, fox eye, etc. In some cases, this may not be possible and the present invention may address them.

In the present invention, the reason why these are possible is as follows. The luminous intensity distribution characteristics of a light source having a longitudinal direction such as a discharge lamp have a uniform range of 45 degrees before and after each direction from a direction perpendicular to the optical axis. Therefore, the brightness does not change even when the lamp shown in FIGS. 1 to 3 is tilted about 45 degrees to the left or right or back and forth, and the function as a headlight can be similarly exhibited.

In this case, however, the parabolic reflecting surface having a focal point near the second focal point of the elliptical reflecting surface may be kept at the focal position and the optical axis may be directed in the traveling direction of the vehicle. Of course it is necessary. In FIG. 1, the four surfaces of the reflecting surfaces 41R, 41L, 42R, and 42L are directed toward the front, and only the shape is adjusted according to the outer shape of the lens.

[0035]

As described above, according to the present invention, the light source is provided so as to have a major axis substantially perpendicular to the central axis of the light source and to substantially surround the light source with the light source as a first focal point. An axis having at least one pair of light-collecting reflecting surfaces of an elliptical system arranged symmetrically with respect to a vertical line passing therethrough, and a focal point at a position substantially coincident with a second focal point of each of the light-condensing reflecting surfaces; And the same number of reflecting mirrors arranged in a substantially linear manner as the parabolic system that substantially matches the irradiation direction of the vehicle headlamp. In the vicinity of the second focal point of the surface, a vehicular headlamp provided with a shielding plate that gives a shape of a light distribution characteristic to the condensing reflection surface is provided. Around the second focal point, which converges again on the outside. By taking out light, the light source is almost completely surrounded by the light-collecting reflective surface, significantly improving the luminous flux capture rate, and eliminating the need for a hood and black stripes. It is possible to realize a brighter headlamp, and to achieve an extremely excellent effect in improving the performance of this kind of vehicle headlamp.

Secondly, the light from the light source is divided into an arbitrary number by the light-collecting reflecting surface and the light is distributed to the same number of irradiation reflecting surfaces. Is smaller and has a shallower depth, so that a wide and low vehicle headlight according to the vehicle design can be realized without lowering the illuminance by means such as arranging the reflecting surfaces for irradiation horizontally. Thus, it is possible to achieve an extremely excellent effect in improving the appearance of the entire vehicle.

Thirdly, by making the shielding plate movable, it is possible to switch between passing light distribution and traveling light distribution only by moving the shielding plate. For example, it is possible to use a light source such as a metal halide discharge lamp. The number can be reduced to the minimum necessary number, and an extremely excellent effect can be achieved in cost reduction.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an arrangement state of each reflecting surface in a vehicle headlamp according to an embodiment of the present invention as viewed from the front.

FIG. 2 is an explanatory diagram showing an arrangement state of each reflection surface in a cross-sectional state along the line AA in FIG. 1 as viewed from above.

FIG. 3 is an explanatory view showing another embodiment of the vehicle headlamp according to the present invention when viewed from the front.

FIG. 4 is a perspective view showing a movable shielding plate as a main part of the present invention.

FIG. 5 is an explanatory diagram showing an operation state of a movable shielding plate.

FIG. 6 is a sectional view showing a conventional example.

FIG. 7 is a sectional view showing another conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Headlight for vehicles 2 ... Light source 3 ... Reflecting surface for condensing 31L, 31R ... Reflecting surface for first condensing 32L, 32R ... Reflecting surface for second condensing 4 ... Reflection for irradiation Surface 41L, 41R... First irradiation reflecting surface 42L, 42R... Second irradiation reflecting surface 5... Shielding plate 6... Movable shielding plate 6a, 6b... Shielding portion 6c.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masato Okamoto 2-9-13 Nakameguro, Meguro-ku, Tokyo Inside Stanley Electric Co., Ltd. (72) Inventor Yoshifumi Kawaguchi 2-9 Nakameguro, Meguro-ku, Tokyo No. 13 F-term in Stanley Electric Co., Ltd. (reference) 3K042 AA08 AC01 AC06 BB03 BB05 BB12 BE01 BE04 BE07 CB07 CB20

Claims (5)

[Claims] 1. A light source having a major axis having an angle of 45 to 135 degrees with a central axis of a light source, the light source being provided as a first focal point and substantially surrounding the light source, each of which is positioned with respect to a vertical line passing through the light source. At least one pair of symmetrically arranged elliptical condensing reflecting surfaces, and a focal point at a position substantially coinciding with a second focal point of each of the condensing reflecting surfaces, and having an axis in front of the vehicle. A light-reflecting light-reflecting surface which is a parabolic system that is substantially coincident with the irradiation direction of the illuminating lamp; , A shielding plate for providing a shape of a light distribution characteristic to the light-collecting reflecting surface is provided in the vicinity of the vehicle headlight. 2. A reflection process for reflecting at least one of the respective shield plates toward the reflecting surface for irradiation with light shielded by the shield plate. 2. The vehicle headlight according to 1. 3. The vehicle headlamp according to claim 1, wherein at least one of the shield plates is movable, and the light distribution characteristic of the vehicle headlight is made variable by the movement. A vehicle headlight as described. 4. The headlight for a vehicle according to claim 1, wherein a plurality of said shielding plates are movable, and said movement is performed by one actuator. 5. The headlight for a vehicle according to claim 1, wherein the light source is a D2S type without a black stripe of a metal halide discharge lamp.