JP3508926B2 - head lamp - Google Patents

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 intended for illumination using a metal halide discharge lamp as a light source, and switching between passing light distribution and traveling light distribution. The present invention relates to the structure of a vehicular lamp having means for changing the light distribution.

[0002]

2. Description of the Related Art A conventional structure of a headlamp 90 of this type is shown in FIG. 13 and an example in which the light source 91 is a discharge lamp such as a metal halide lamp and the headlamp 90 is dedicated to passing light distribution. In FIG. 14, a parabolic reflection surface 92 such as a paraboloid of revolution having a focal point f at the rear is provided for the arc 91a of the light source 91.

By doing so, a downward ray is generated from the upper half of the parabolic reflecting surface 92 and an upward ray is generated from the lower half of the parabolic reflecting surface 92, so that the light source 91 (arc 91a) is shielded downward by the shield plate 93. Is provided to block light from reaching the lower half of the parabolic reflection surface 92. In addition, the light source 91
Also, a stripe 91b made of black opaque paint or the like is provided and has a part of the function of the shielding plate 93. In addition, the light source 91 is provided with a hood 94 that blocks direct light.

With this structure, as shown in FIG. 14, the light reaches the parabolic reflection surface 92 substantially only in the upper half, that is, most of the light is a downward ray and the passing light distribution is performed. Will be obtained. In FIG. 14, a part of the lower half portion of the parabolic reflection surface 92 where light reaches reaches the roadside belt side in order to facilitate visual recognition of road signs and the like installed on the roadside belt. This is a part for forming a light distribution called an elbow that emits upward light.

[0005]

However, in the above-described conventional headlamp 90, only about half of the parabolic reflection surface 92 is used to obtain the passing light distribution, and therefore, it is essential. In addition, the luminous flux utilization rate for the light source 91 was low. In addition, in recent years, since it is recognized that the headlamp 90 also plays a part in the design of the vehicle, for example, there is a strong demand for reducing the size in the vertical direction, so that the area of the parabolic reflection surface 92 should be reduced. As a result, the problem that the illuminance of the headlamp 90 becomes insufficient becomes more and more prominent.

Further, since there is only one light source, it is difficult to switch between the passing light distribution and the traveling light distribution. For example, a means for separately providing a headlight (not shown) for traveling light distribution. However, in this case, if the headlamp light source for traveling light distribution is also not a discharge lamp, the color of the light will be different, causing a problem that the driver and the viewer will feel uncomfortable. In the case of standardizing the discharge lamp as the discharge lamp, there is a problem that the cost of the headlamp increases considerably.

[0007]

As a concrete means for solving the above-mentioned conventional problems, the present invention has a main reflection surface, which is a parabolic surface having a light source of a bulb as a focal point, in a substantially upper half portion. The headlamp is a headlamp provided with a right elliptical reflecting surface and a left elliptical reflecting surface, each of which has a first focal point in the vicinity of the light source of the bulb as a center line of the headlamp. The right elliptical reflecting surface is provided with a second focal point on an appropriate right side of the bulb, and the left elliptical reflecting surface is provided with a second focal point on an appropriate left side of the bulb. , A right parabolic reflection surface having a focus at the second focus of the right elliptical reflection surface is provided on the lower right side of the main reflection surface, and a second focus of the left elliptical reflection surface is provided on the lower left side of the main reflection surface. left parabolic reflecting surface whose focal point is provided, said bar To form the passing light distribution in Bed downward
Is provided with a shield plate for
Securing the optical path of the light reflected by the reflecting surface and reaching the parabolic reflecting surface
Is placed near one of the focal points of the elliptical reflecting surface in order to
The right parabolic reflection surface and the left parabolic reflection surface have substantially parallel optical paths or intersect in front of the headlamp, and the two parabolic reflection surfaces are provided. The problem is solved by providing a headlamp characterized in that at least a part of the optical path from the surface is provided with a light distribution variable means by a reflecting means or a refracting means.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail based on the embodiments shown in the drawings. 1 and 2 show the basic configuration of the headlamp 1 according to the present invention except the light distribution changing means 10. In this embodiment, the headlamp 1 is a discharge lamp such as a metal halide lamp. Although the description will be made assuming that a certain bulb 2 is used as a light source, it goes without saying that the same configuration can be applied to an incandescent light bulb such as a halogen light bulb.

Also in this headlamp 1,
A main reflecting surface 3 such as a paraboloid of revolution having a focal point f set as an appropriate rear of the arc 2a which is the light emitting source of the bulb 2.
However, in the present invention, the main reflection surface 3 is formed only as an upper half part including a lower half part forming the elbow described in the conventional example. ing.

In addition, a shielding plate 4 is provided to cover the lower part of the bulb 2 and to form a light distribution by passing through a stripe (not shown) provided on the bulb 2. Although similar to the conventional example, the shielding plate 4 is provided with an opening 4a, which will be described in detail later, at an appropriate position and an appropriate hole diameter.

In addition, a hood 5 is provided in front of the light source 2 for preventing direct light from the arc 2a from being emitted to the outside and causing a driver of an oncoming vehicle to be dazzled. However, in the present invention, a part of the hood 5 has a pair of elliptical reflecting surfaces 6 such as a spheroidal surface having the arc 2a as the first focal point f1, that is, a right elliptical reflecting surface 6R and a left elliptical reflecting surface. And a surface 6L. In this description, the left and right names are based on the state where the headlamp 1 is viewed from the front.

Here, the structure of the elliptical reflecting surface 6 (R, L) will be described. First, as shown in FIG. 1, the right elliptic reflecting surface 6R, which is one of the pair, forms an arc at the first focal point f1. 2a
, And the second focal point f2 is located at an appropriate right side of the bulb 2. Therefore, the long axis Zr of the right elliptical reflecting surface 6R is a left-upward one when the headlamp 1 is viewed from the front.

The left elliptical reflecting surface 6L which is the other of the pair.
Positions the first focal point f1 at the arc 2a and the second focal point f2 at an appropriate left side of the bulb 2 so that the major axis Zl is leftward. At this time, since the two elliptical reflecting surfaces 6 (R, L) are basically the same in shape, they are joined at the vertical center line of the headlamp 1.

Further, as shown in FIG. 2, the ends of the two elliptical reflecting surfaces 6 (R, L) near the main reflecting surface 3 are located at the substantially center of the arc 2a and the outer end of the main reflecting surface 3. It is arranged in the vicinity of the connecting line X so as not to block the luminous flux emitted from the arc 2a toward the main reflecting surface 3.

Then, the second focal point f2 of the right elliptical reflecting surface 6R.
Corresponding to, a right parabolic reflection surface 7R is provided, which is a rotation parabolic surface or the like having the second focus f2 as a focal point and having an axis substantially the same as the irradiation direction of the headlamp 1, and a left elliptical reflection surface 6L. Corresponding to the second focal point f2, the left parabolic reflecting surface 7L having the same configuration as the right parabolic reflecting surface 7R having the second focal point f2 as the focal point f2.
Is provided.

At this time, in the present invention, as described above, the main reflection surface 3 is provided with substantially only the upper half portion, and therefore corresponds to the position of the omitted lower half portion. It is provided so as not to cause optical interference with the main reflection surface 3.

Here, when the optical path from the elliptical reflecting surface 6 (R, L) to the parabolic reflecting surface 7 (R, L) is examined in detail, the shielding plate 4 exists between them. Therefore, what is provided is the opening 4a, and the elliptical reflecting surface 6 is provided.
It is provided to secure the optical path of the light reflected by (R, L) and reaching the parabolic reflection surface 7 (R, L).

Since the opening 4a is provided,
Direct light from the arc 2a also leaks from the opening 4a, which may impair the function of the shield plate 4. Therefore, when setting the shape of the elliptical reflecting surface 6 (R, L), the second focus f is provided in the vicinity of the shielding plate 4.
There shall be two.

On the contrary, in setting the shape of the shielding plate 4, assuming that the shielding plate 4 exists near the second focal point f2, the second focal point f2 has an elliptical reflecting surface 6 (R, L). Since the reflected light from (1) is converged, the aperture of the opening 4a can be made small, and the influence of light leakage can be made small.

With the above structure, the headlamp 1 of the present invention is provided with the elliptical reflecting surface 6 (R, L) so as to cover the bulb 2 from the upper front side. The light (R, L) is not captured by the main reflection surface 3 and has a directivity that may become direct light, that is, the light flux from the bulb 2 which has been conventionally ineffective is captured and emitted. The light is given to the object reflection surface 7 (R, L) and can be used as irradiation light of the headlamp 1.

Further, since the elliptical reflecting surface 6 (R, L) is set so as to capture light in a range that the main reflecting surface 3 does not capture, for example, the main reflecting surface 3 is downsized. When the amount of captured light flux decreases, the elliptical reflecting surface 6 (R,
It is also possible to make up for it with L), which makes it possible to ensure the headlamp 1 with a required level of brightness. The reference numeral 10 in the figure denotes a light distribution changing means which will be described in detail below.

FIG. 3 shows a first embodiment in which the light distribution changing means 10 is incorporated in the basic structure described above and the headlamp 1 is of a variable light distribution type. In this first embodiment, The light distribution changing means 10 is composed of, for example, a rotating mirror 11 which is rotated by a motor 12 or the like which is interlocked with a steering wheel operation, and is always provided with the parabolic reflection surface 7 (R,
It is supposed to exist in the optical path from L).

In this case, the parabolic reflection surface 7 (R,
The light from L) is brought into contact with the rotating mirror 11, and the light distribution characteristics are changed by setting the angle of the rotating mirror 11 when reflected, so that the light sufficiently comes into contact with the rotating mirror 11. As described above, it is effective that the light flux from the parabolic reflection surface 7 (R, L) intersects in the vicinity of the rotating mirror 11.

In the first embodiment, the rotating mirror 11 will be described as a flat plate having both the front surface 11a and the rear surface 11b as mirror surfaces. However, for example, the light after being reflected has a horizontal direction. It is possible to provide appropriate irregularities for the purpose of diffusion, or to provide an appropriate curved surface along the traveling direction of light from the parabolic reflection surface 7 (R, L).

FIGS. 4 to 7 show the operation and effect of the first embodiment having the above-described structure. First, as shown in FIG. 4, when the handle or the like is not operated, the rotary mirror 11 is operated. Is a reflecting surface 11a with respect to the traveling direction of the vehicle,
11b is parallel. Therefore, the parabolic reflection surface 7 (R,
The light from L) is emitted to the outside from the headlamp 1 in a state where the light is reflected by the reflecting surfaces 11a and 11b and the direction thereof is reversed, and as shown in FIG. At the same time, for example, a passing light distribution is formed as the light distribution Hr and the light distribution Hl.

When the steering wheel or the like is turned to make a left turn, for example, the rotary mirror 11 also turns in the turning direction of the vehicle as shown in FIG. 6, and is released as shown in FIG. Light distribution Hr from object reflection surface 7R
Also, the light distribution Hl from the parabolic reflection surface 7L is shifted to the left with respect to the light distribution Hm from the main reflection surface 3. Therefore, the traveling direction of the vehicle from now on is widely illuminated, which is effective for traveling on a curved road.

FIG. 8 shows a second embodiment of the headlamp 1 according to the present invention. In the previous first embodiment, the rotating mirror 11 which is a reflecting means always has a parabolic reflection surface 7 (R,
It exists in the optical path from L), and the course of the light is changed by rotating as necessary. In contrast,
In the second embodiment, the reflecting means is a movable mirror 13 that can be moved in and out of the parabolic reflection surface 7 (R, L) in the optical path as needed. In the second embodiment, the light from the parabolic reflection surface 7 (R, L) will be described as parallel light traveling in the front direction of the headlamp 1.

Further, in the second embodiment, the movable mirror 13 is formed in a substantially wedge shape in a horizontal cross section whose vertex is on the bulb 2 (light source) side. However, depending on the need for forming the light distribution characteristic, the wedge shapes with different angles of the above-mentioned vertices may be stacked, or the apex angle may be continuously increased as it goes downward.

The movable mirror 13 formed as described above
Corresponds to the speed of the vehicle, for example, is inserted during low speed traveling and exits during high speed traveling so that the parabolic reflection surface 7
It is moved in and out of the optical path from (R, L). By doing so, as shown in FIG.
The light from (R, L) is the light distribution Hm from the main reflection surface 3.
When the vehicle is traveling at a high speed, it becomes a high-speed light distribution Hh that illuminates a road surface in front of the vehicle in a traveling direction in a spot manner. The two low-speed light distributions Hd for illumination can be obtained.

FIG. 10 shows a third embodiment of the headlamp 1 according to the present invention. In both of the first and second embodiments, the light distribution changing means 10 is a rotating mirror 11, a movable mirror 13 and other reflecting means. However, the present invention is not limited to this, and refracting means such as a lens may be adopted.

In the third embodiment, the light distribution changing means 10 is similar to the second embodiment in the optical path from the parabolic reflection surface 7 (R, L) by the driver's operation, for example. It is a movable lens 14 which is moved in and out by such a mechanism and has a cylindrical lens shape with its axis in the vertical direction. Incidentally, also in the third embodiment, the parabolic reflection surface 7
It is assumed that the light from (R, L) is parallel light heading in the front direction of the headlamp 1.

Here, in the third embodiment, as shown in FIG. 11, the movable lens 14 has a shape in which a substantially circular arc having a gradually increasing curvature appears in the horizontal cross section, and the movable lens 14 has a vertical cross section. Is said to have a prismatic shape that enhances the degree to which light is refracted downward. The movable lens 14 is maximally inserted into the light flux from the parabolic reflection surface 7 (R, L) when traveling in urban areas. The movable lens 14 is operated by operating a switch or the like when the driver finds it necessary, such as when traveling in the suburbs or traveling on an expressway.
It is assumed that the light flux exits from L).

FIG. 12 shows a light distribution state in the third embodiment configured as described above. First, when the movable lens 14 is inserted while driving in an urban area, the parabolic reflection is performed. The light flux from the surface 7 (R, L) is diffused to the left and right, and is also refracted downward, so that a light distribution Hp that illuminates the front of the vehicle with downward light in a wide range is obtained.

At this time, since the light from the main reflecting surface 3 forms a passing light distribution Hm, the light distribution Hp from the parabolic reflecting surface 7 (R, L) which is downward and has a wide width in the horizontal direction. The function as the passing light distribution is not lost even when the light beams are overlapped with each other, the brightness is further increased due to the above-mentioned overlap, and the visibility is improved.

Here, when the driver operates the vehicle, for example, by getting on a highway, the movable lens 14 starts to exit from the light flux from the parabolic reflection surface 7 (R, L).
Along with this, the light from the parabolic reflection surface 7 (R, L) gradually narrows the irradiation width in the horizontal direction, and changes the irradiation direction from the downward direction to the horizontal direction, and becomes a spot shape when the exit is completed. The light distribution Hu illuminates the front of the vehicle, and the light distribution Hm from the main reflecting surface 3 becomes a traveling light distribution, which makes it possible to switch between the passing light distribution and the traveling light distribution.

[0036]

As described above, according to the present invention, there is provided a headlamp in which a main reflection surface, which is a parabolic surface having a light source of the bulb as a substantially focal point, is provided in a substantially upper half portion of the bulb. A right elliptical reflection surface and a left reflection elliptical surface, each of which has a first focal point in the vicinity of the light emission source of the bulb, are provided in a shape that is connected substantially along the center line of the headlamp, in the front upper part. The elliptical reflecting surface is provided with a second focus on an appropriate right side of the bulb, and the left elliptical reflecting surface is provided with a second focus on an appropriate left side of the bulb. A right parabolic reflection surface having a second focus of the elliptical reflection surface as a focus is provided, and a left parabolic reflection surface having a second focus of the left elliptical reflection surface as a focus is provided on the lower left side of the main reflection surface. , The optical path of the reflected light from the right parabolic reflection surface and the left parabolic reflection surface A head that is substantially parallel or intersects in front of this headlamp, and at least a part of the optical path from the two parabolic reflection surfaces is provided with a light distribution variable means by a reflection means or a refraction means. First of all, by using a lamp, the elliptical reflecting surface collects the light emitted upward and forward from the bulb that was not used because it was shielded by the hood etc. as a factor of generating dazzling light in the past. However, by making the parabolic reflection surface usable as irradiation light, the brightness is increased, and an extremely excellent effect for improving the performance of this type of headlamp is exhibited.

Further, since the parabolic reflection surface is provided in a portion that does not interfere with the main reflection surface, a mirror, a lens, etc. for converting the light distribution characteristic are installed in the optical path from this parabolic reflection surface. As a result, a heading of this kind is considered to have a plurality of applications such as a function of a cornering lamp, a passing light distribution corresponding to the traveling speed of a vehicle, or switching between a passing light distribution and a traveling light distribution. It is also very effective in improving the function of the lamp.

[Brief description of drawings]

FIG. 1 is a front view showing a basic form of a headlamp according to the present invention.

FIG. 2 is a cross-sectional view taken along the line AA of FIG.

FIG. 3 is a perspective view showing a first embodiment of a headlamp according to the present invention.

FIG. 4 is an explanatory view showing the main part of the same non-driving state of the first embodiment.

FIG. 5 is an explanatory diagram showing a light distribution shape when not driven.

FIG. 6 is an explanatory view showing a main part of a driving state of the same first embodiment.

FIG. 7 is an explanatory diagram showing a light distribution shape during driving.

FIG. 8 is a perspective view showing a second embodiment of the headlamp according to the present invention.

FIG. 9 is an explanatory diagram showing a light distribution shape obtained according to the second embodiment.

FIG. 10 is a perspective view showing a third embodiment of the headlamp according to the present invention.

FIG. 11 is a perspective view showing a main part of a third embodiment.

FIG. 12 is an explanatory diagram showing a light distribution shape obtained according to the third embodiment.

FIG. 13 is a cross-sectional view showing a conventional example.

FIG. 14 is an explanatory diagram showing how the light source light reaches the reflecting surface in the conventional example.

[Explanation of symbols]

1 ... Headlamp 2 ... Valve 2a ... Ark 3 ... Main reflective surface 4 Shield plate 4a ... opening 5 ... Hood 6 ... Elliptical reflective surface 6R: Right elliptical reflective surface 6L: left elliptical reflective surface 7: Parabolic reflection surface 7R: Right parabolic reflective surface 7L: left parabolic reflective surface 8 ... Mounting part 10 ... Variable light distribution means 11 ... Rotating mirror 12 ... motor 13 ... Movable mirror 14 ... Movable lens

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI F21V 14/00 F21M 3/20 Z 14/04 // F21W 101: 10 F21Y 101: 00 (58) Fields investigated (Int.Cl . ^7, DB name) F21S 8/10 F21S 8/12 F21V 7/00 F21V 7/16 F21V 13/00 F21V 14/00 F21V 14/04 F21W 101: 10 F21Y 101: 00

Claims (7)

(57) [Claims] 1. A headlamp comprising a main reflection surface, which is a parabolic surface having a light emission source of the bulb as a substantially focal point and is provided in a substantially upper half portion, wherein each of the bulbs is provided in an upper front portion of the bulb. Is provided with a right elliptical reflecting surface and a left elliptical reflecting surface having a first focal point in the vicinity of the light source as a shape connected substantially along the center line of the headlamp, and the right elliptic reflecting surface has a second focal point as the bulb. Is provided on the appropriate right side, the left elliptical reflecting surface is provided with a second focus on the appropriate left side of the bulb, and the second focal point of the right elliptical reflecting surface is the focus on the lower right side of the main reflecting surface. A right parabolic reflection surface is provided, and a left parabolic reflection surface having a second focal point of the left elliptical reflection surface as a focus is provided on the lower left side of the main reflection surface, and below the bulb.
Is provided with a shielding plate for forming a passing light distribution,
The shielding plate reflects the elliptical reflection surface to reflect the parabolic reflection.
The elliptical reflecting surface to secure the optical path of the light reaching the surface.
And an optical path of reflected light from the right parabolic reflection surface and the left parabolic reflection surface is substantially parallel or intersects in front of the headlamp. A headlamp characterized in that at least a part of an optical path from the two parabolic reflecting surfaces is provided with a light distribution variable means by a reflecting means or a refracting means. 2. The light distribution varying means is a reflecting means, is a rotating mirror provided in the optical path from the two parabolic reflecting surfaces, and having a rotation axis in the vertical direction and both front and back surfaces as reflecting surfaces. The headlamp according to claim 1, which is characterized in that: 3. The light distribution changing means is a reflecting means, and is a movable mirror having a substantially wedge shape whose tip is on the light source side and is provided so as to be able to move in and out of the optical path from the two parabolic reflection surfaces. The headlamp according to claim 1, wherein 4. The headlamp according to claim 3, wherein the movable mirror has a plurality of apex angles stepwise or gradually. 5. The variable light distribution means is a refracting means, and is a movable lens having a substantially cylindrical lens shape which is provided so as to be able to move in and out of an optical path from the two parabolic reflection surfaces. The headlamp according to 1. 6. The headlamp according to claim 5, wherein the movable lens has a plurality of curvatures stepwise or gradually. 7. The head according to claim 1, wherein the light distribution variable means includes means for changing an optical path from the two parabolic reflection surfaces upward or downward. lamp.