JPH0410164B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The vehicle headlamp of the present invention will be explained in accordance with the following items.

A. Industrial field of application B. Overview of the invention C. Prior art [Figures 12 and 13] D. Problems to be solved by the invention [Figures 12 and 13]
[Fig. 13] E Means for solving the problem F Example F-1 First embodiment [Figs. 1 to 4] a Reflector b Light shield c Projection lens d Effect e Modification [Fifth Figures to Figures 7] e-1 Structure e-2 Effect F-2 Second embodiment [Figures 8 to 11] a Reflector b Light shield c Projection lens d Effect G Effects of the invention (A Industrial) FIELD OF THE INVENTION The present invention relates to a novel vehicle headlamp. Specifically, the light from the light source is reflected by a reflecting mirror and focused on a light-concentrating area in front, and the light-blocking edge of the light-blocking body is positioned near the light-concentrating area, so that the focal area is located at the light-blocking edge of the light-blocking body. In a vehicle headlamp that projects light from the light shielding body and its vicinity forward by a projection lens located close to the light source, the light blocked by the light shielding body is minimized, and the light source is It is an object of the present invention to provide a novel vehicle headlamp that can effectively use emitted light and easily spread the light distribution pattern to the left and right.

(B Summary of the Invention) The vehicle headlamp of the present invention has a reflector that reflects light from a light source and focuses it on a light-concentrating area in front, and a light-shielding edge of a light-shielding body near the light-concentrating area. A vehicle headlamp that projects the condensed light on the light shielding body and its vicinity forward by a projection lens whose focal region is located close to the light shielding edge of the light shielding body, wherein the reflecting mirror is It has a common optical axis and a common light source arrangement area, and is composed of a plurality of vertically divided reflecting surfaces, and the light collecting area of the reflecting surface is near the light-blocking edge of the light-blocking body, and the focal area of the projection lens is By doing so, the proportion of light reflected by each reflective surface being blocked by the light shielding body is reduced, and the light is used effectively. It is possible to easily obtain a spread of the light distribution pattern to the left and right by projecting the reflected light from the mirror to the left and right.

(C Prior Art) [Figures 12 and 13] A reflecting mirror reflects the light from the light source and focuses it on a light-concentrating area in front, and a light-blocking edge of a light-blocking body is placed near the light-concentrating area. A vehicle headlamp that projects light from the light shielding body and its surroundings forward using a projection lens whose focal region is located close to the light shielding edge of the light shielding body, Since the light-dark boundary line defined by the light-shielding edge is clearly expressed, it is suitable as a headlamp for automobiles, particularly for emitting low beam beams.

FIG. 12 shows an example a of such a projection type vehicle headlamp.

b is a reflecting mirror, and the reflecting surface c is an ellipsoid of revolution.
A light source d is placed at the first focal point _F1 of the reflecting surface c.

Therefore, the light e emitted from the light source d and reflected by the reflecting surface c is focused at the second focal point _F2 .

f is a light shielding body disposed in front of the reflecting mirror b, and the upper edge of the light shielding body f, that is, the light shielding edge g is located near the second focal point _F2 of the reflecting surface c.

h is a convex projection lens disposed in front of the light shield f, and its focal point F _c is located at the light shield edge g of the light shield f.

In the case of the vehicle headlight a, the lower side of the light beam before or after converging on the second focal point _F2 of the reflective surface c is blocked by the light shield f, and the image thereof is The light is projected forward by the projection lens b to form a light distribution pattern i shown in FIG. 13. Note that in this light distribution pattern i, j is a bright/dark boundary line defined by the light-shielding edge g of the light-shielding body f.

(D Problems to be solved by the invention) [12th
[FIG. 13] However, the conventional vehicle headlight a described above has a problem in that much of the light is wasted.

For example, if the second focal point _F2 of the reflective surface c is located in front of the light shielding edge g of the light shielding body f, that is, closer to the first focal point _F1 , most of the light _e1 reflected by the upper half of the reflective surface c is The second focal point _F2 of the reflective surface c is blocked by the light shield f (indicated by a two-dot chain line).
If it is located beyond the light-shielding edge g, that is, closer to the projection lens h, most of the light _e2 reflected on the lower half of the reflecting surface c will be blocked by the light-shielding body f (the one shown by the two-dot chain line). I end up.

Therefore, in the conventional vehicle headlamp a, there is a problem in that much of the light e is not projected forward and becomes wasted light.

Furthermore, in the vehicle headlight a, a vertical section of the bundle of light e at the portion where the light shielding edge g of the light shield f is located is projected forward by the projection lens h. Therefore, there is a limit to the spread of the light distribution, and there is a problem in that it is not possible to obtain a sufficient spread of the light distribution in the left and right direction.

(E. Means for Solving Problems) In order to solve the above-mentioned problems, the vehicle headlight of the present invention reflects light from a light source using a reflecting mirror and focuses it on a light condensing area in front. The light-blocking edge of the light-blocking body is positioned near the light-converging area, and the light-blocking body and its vicinity are focused forward by a projection lens whose focal area is located close to the light-blocking edge of the light-blocking body. The reflecting mirror has a common optical axis and a common light source arrangement area, and is composed of a plurality of vertically divided reflecting surfaces, and the light-converging area of the reflecting surface is light-blocking. It is located near the light-shielding edge of the body, and is located in front and behind the focal range of the projection lens.

Therefore, according to the vehicle headlamp of the present invention, the light reflected by each reflective surface is blocked by the light shielding body to block only the minimum amount of light reflected by the reflective surface to create a bright/dark boundary line. Light can be used effectively by reducing the proportion of light that is blocked by the body.

(F. Embodiment) Details of the vehicle headlamp of the present invention will be described below with reference to illustrated embodiments.

(F-1 First Embodiment) [Figures 1 to 4] Figures 1 to 4 show an example 1 in which the present invention is applied to an automobile headlamp for irradiating a low beam. It shows.

(a reflecting mirror) 2 ₁ and 2 ₂ are reflecting mirrors.

The reflecting mirror 2 ₁ has a reflecting surface 3 ₁ in the shape of approximately the lower half of an ellipsoid of revolution, and the reflecting mirror 2 ₂
is a reflecting surface 3 that is approximately in the shape of the upper half of an ellipsoid of revolution.
It has ₂ . These two reflecting mirrors 2 ₁ and 2 ₂ are integrally joined at the top and bottom,
And they have a common optical axis x-x.

Further, the reflecting surfaces 3 ₁ and 3 ₂ of these two reflecting mirrors 2 ₁ and 2 ₂ have a common first focal point f ₀ , and their second focal points are located at different positions. That is, the reflecting surface 3 ₁ of the lower reflecting mirror 2 ₁
The second focal point f ₁ is located in front of the second focal point f 2 of the reflecting surface 3 ₂ of the upper reflecting mirror _{2 2} , that is, closer to the reflecting mirror 2 .

4 is the first common to the above two reflecting surfaces 3 ₁ and 3 ₂
A light source located at the focal point f ₀ , for example the filament of a light bulb.

Therefore, light is emitted from the light source 4 and the lower reflecting mirror 2 ₁
The light 5 ₁ , 5 ₁ , . . . reflected by _the reflecting surface _{3 1 of} The light beams 5 ₂ , 5 ₂ , . . . are focused on the second focal point f ₂ .

Although the light is focused on the second focal point f ₁ or f ₂ , since the light source 4 is not a point light source, the second focal point f ₁
Therefore, at _f2 , the light is focused in a range with a certain degree of spread in a plane perpendicular to the optical axis x-x.

(b Light-shielding body) 6 is a light-shielding body, and its upper edge 7 is used as a light-shielding edge. Then, the light shielding body 6 has its light shielding edge 7
is located approximately midway between the second focal points f ₁ and f ₂ of the reflective surfaces 3 ₁ and 3 ₂ so as to be approximately in contact with the optical axis x-x from below.

Therefore, the second focal points f ₁ and f ₂ of the reflecting surfaces 3 ₁ and 3 ₂
Light condensed on 5 ₁ , 5 ₁ , ... and 5 ₂ , 5 ₂ , ...
... is a location where the light shielding body 6 is located, and the vicinity of the lower edge thereof is blocked by the light shielding body 6. Therefore, reflecting mirror 2
When the lights 5 ₁ , 5 ₁ , ... reflected by the reflective surface 3 ₁ of ₁ are viewed in a cross section perpendicular to the optical axis x-x after passing the second focal point f ₁ , the lights 5 ₁ , 5 1 , . . . The light 5 ₂ , 5 ₂ , ... reflected by the reflecting surface 3 ₂ of the reflecting mirror 2 ₂ has a cross section perpendicular to the optical axis x-x after passing the second focal point f ₂ . When you look at it, it shows a cluster like ₈₂ shown in Figure 3B.
Then, the cluster of light 8 ₂ near the lower edge of 1
The edge 9 ₁ shown by the dotted chain line and the edge 9 ₂ shown by the double dot chain line near the upper edge of the light cluster 8 ₂ are blocked by the light shielding body 6 in the lower and upper parts thereof. It was completed.

In this way, the bundles 8 ₁ and 8 ₂ of the light reflected by the respective reflecting mirrors 2 ₁ and 2 ₂ originally have a semicircular shape, and only the tip of a small portion near the linear edge is covered with a light shield. 6, the light utilization efficiency is extremely good.

(c Projection Lens) 10 is a projection lens in the shape of a convex lens, which is placed in front of the light shielding body 6, and its focal point f _c
is located approximately at the center of the light shielding edge 7 of the light shield 6 on the left and right sides.

(D Effect) In the automobile headlamp 1, when the light source 4 is turned on, a light distribution pattern 11 shown in FIG. 4 is projected by the projection lens 10. 12 ₁ of the light distribution patterns 11 are reflective mirrors 2 ₁
The reflected light 5 ₁ , 5 ₁ , ... by the reflecting mirror 2 ₂ is the projected light distribution part, and 12 ₂ is the light distribution part on which the reflected light 5 ₂ , 5 ₂ , ... by the reflecting mirror 2 2 is projected. .

That is, the reflected lights 5 ₁ , 5 ₁ , ... are reflected from the projection lens 1
Point f ₁ outside the focal point f _c of 0 (second focal point of reflective surface 3 ₁ )
, and then enters the projection lens 10 , so the pattern of the bundle of light 8 ₁ (the lower edge is limited by the line 9 ₁ ) is reversed by the projection lens 10 both vertically and horizontally. is projected. Also, the reflected lights 5 ₂ , 5 ₂ , ... are reflected at a point f ₂ (the second point of the reflective surface 3 ₂ ) inside the focal point f _c of the projection lens 10.
Since the light enters the projection lens 10 after being condensed at the focal point (focal point), the pattern of the bundle of light 8 ₂ (the upper edge is limited by the line 9 ₂ ) is not reversed; It is projected slightly enlarged left and right and downward.

As a result of the above, the light distribution pattern 11 as shown in FIG. 4 is projected, spreading to the left and right is obtained, and the light is utilized with almost no waste.

(e Modification) [Figures 5 to 7] Figures 5 to 7 show the above-described first embodiment 1.
This shows a modification example 1A.

(e-1 Configuration) This modification 1A is different from that of the above-described embodiment in terms of the reflecting mirror.

That is, on the left side of the reflecting mirrors 2 ₁ and 2 ₂ , the upper reflecting mirror 2 ₂ extends below the horizontal plane 13 including the optical axis x-x, and directly faces the reflecting mirror 2 at its lower left end. A line 14 connecting the center and the center is inclined downward by about 15 degrees with respect to the horizontal plane 13.

Therefore, according to the reflecting mirrors 2 ₁ and 2 ₂ as described above, the reflected lights 5 ₁ , 5 ₁ , . . . and _{5 2} , 5 _{2 ,} . As shown in FIGS. 6A and 6B, the pattern of the light clusters 15 ₁ and 15 ₂ is closer to the light distribution pattern, and accordingly, there is less light to be blocked by the light shielding body 6, which makes it more efficient. It is possible to utilize light.

(e-2 Effect) Therefore, in the case of the above automobile headlamp 1A, the light distribution patterns 16 and 1 shown in FIG. 7A and B are
7 is projected.

Among these, the light distribution pattern 16 in FIG. 7A is the case where the light shielding edge 7 of the light shielding body ₆ is located near the second focal point _f1 of the reflective surface 31, and ₁₈₁ of this is due to the reflective surface ₃₁ . Due to reflected light 5 ₁ , 5 ₁ , ...
In addition, 18 ₂ is the reflected light 5 ₂ , 5 by the reflecting surface 3 _2
2. This is the light distribution part by...

Furthermore, the light distribution pattern 17 in FIG. 7B is a case where the light shielding edge 7 of the light shielding body ₆ is located near the second focal point f2 of the reflective surface ₃₂ , of which ₁₉₁ is the light reflected by the reflective surface ₃₁ . 5 ₁ , 5 ₁ , ..., and 19 ₂ is the reflected light 5 ₂ , 5 by the reflecting surface 3 _2
2 , the orientation part due to...

(F-2 Second Embodiment) [Figures 8 to 11] Figures 8 to 11 show an automobile headlamp 20 according to a second embodiment of the vehicle headlamp of the present invention. It is something.

(a reflecting mirror) 21 and 22 are reflecting mirrors, 21 is in the center,
Further, 22 is located on the left and right sides of 21.

The reflecting mirror 21 is equipped with reflecting surfaces 23, 23 which form approximately one-third of the upper and lower portions of an ellipsoid of revolution, and the two sides of the reflecting surfaces 23, 23 are separated from each other by a large distance vertically.

The reflecting mirror 22 is provided with reflecting surfaces 24, 24 each forming about a quarter of the left and right sides of an ellipsoid of revolution.

Then, the side edges of the reflective surfaces 23, 23 and the reflective surface 2
The upper and lower edges of 4 and 24 are connected by connecting portions 25 and 25 that are substantially horseshoe-shaped in plan view.

Each of the reflecting surfaces 23, 23, 24, 24 has a common first focal point f ₀ and a common optical axis x-x, and a second focal point f ₁ of the reflecting surfaces 23, 23.
and the second focal point _f2 of the reflecting surfaces 24, 24 are the optical axis x-
They are spaced apart from each other on x. Here, the second focal point f ₁ of the reflecting surfaces 23, 23 is located in front of the second focal point f ₂ of the reflecting surfaces 24, 24, that is, closer to the reflecting mirrors 21, 22.

26 is a light source placed at the first focal point f ₀ .

Therefore, among the light emitted from the light source 26, the light 27 ₁ , 27 1 , reflected by the reflecting surfaces 23 , ₂₃ ,
... is the light 27 2 that is focused at the second focus f ₁ of the reflective surfaces 23, 23 and reflected by the reflective surfaces 24, ₂₄ ,
27 ₂ , ... is the second focal point f ₂ of the reflecting surfaces 24, 24
to focus the light.

(b Light shielding body) 28 is a light shielding body, the upper edge 29 of which is a light shielding edge, which is similar to the light shielding body 6 in Example 1.
It is almost the same as .

The light shielding body 28 is the second focal point f ₁
and f ₂ , the light-shielding edge 29 is directed from below to the optical axis x
- It is located so as to be approximately in contact with x.

(c Projection lens) 30 is a projection lens, which is also the first lens.
The projection lens 10 in Example 1 is substantially the same.

The projection lens 30 is connected to the light shielding body 2.
8, and its focal point f _c is placed in front of the light shielding body 2
It is located approximately at the center in the left-right direction of the light-shielding edge 29 of No. 8.

(d Effect) In the above-mentioned automobile headlamp 20, a light distribution pattern 31 shown in FIG. 11 is projected. Incidentally, among this light distribution pattern 31,
32 ₁ is the reflected light 27 ₁ , 27 from the reflecting surfaces 23 , 23
₁ ,..., and 32 ₂ is the reflective surface 24, 2
This is the light distribution portion caused by the reflected lights 27 ₂ , 27 ₂ , . . .

(G. Effects of the invention) As is clear from the above description, the vehicle headlamp of the present invention reflects light from a light source using a reflecting mirror and focuses the light on a condensing area in front of the vehicle. For vehicles in which the light blocking edge of the light blocking body is located near the light condensing area, and the light blocking body and the condensed light in the vicinity thereof are projected forward by a projection lens whose focal area is located close to the light blocking edge of the light blocking body. In the headlamp, the reflecting mirror has a common optical axis and a common light source arrangement area, and is composed of a plurality of vertically divided reflecting surfaces, and the light converging area of the reflecting surface is located at the light-blocking edge of the light-blocking body. It is characterized in that it is located in the vicinity and in front and behind the focal range of the projection lens.

Therefore, according to the vehicle headlamp of the present invention, the light reflected by each reflective surface is blocked by the light shielding body to block only the minimum amount of light reflected by the reflective surface to create a bright/dark boundary line. Light can be used effectively by reducing the proportion of light that is blocked by the body.
Furthermore, if necessary, the reflected light from each reflecting surface can be projected separately to the left and right, thereby easily expanding the light distribution pattern to the left and right.

Incidentally, in the description of each of the above embodiments, each of the reflecting mirrors has been explained as having a reflecting surface in the shape of an ellipsoid of revolution. Therefore, it is not limited to those having a spheroidal reflecting surface as long as it can perform such a function. For example, an ellipse-parabola compound surface (a surface that forms an ellipse in the vertical section and a parabola in the horizontal section), an ellipse-parabola compound surface (a surface that forms an ellipse in the vertical section and a parabola in the horizontal section), and an ellipse-parabola compound surface (a surface that forms an ellipse in the vertical section and a parabola in the horizontal section).
Various surfaces such as a hyperbolic compound surface (a surface that forms an ellipse in a vertical cross section and a hyperbola in a horizontal cross section) are applicable.

[Brief explanation of drawings]

Figures 1 to 4 show a first diagram of a vehicle headlamp according to the present invention.
FIG. 1 is a schematic perspective view, FIG. 2 is a schematic vertical sectional view, FIGS. 3A and B are diagrams each explaining the pattern of light clusters after focusing, and FIG. The figures are light distribution pattern diagrams, figures 5 to 7.
The drawings show a modification of the first embodiment, Fig. 5 is a schematic perspective view, Fig. 6 A and B are diagrams each explaining the pattern of light clusters after focusing, and Fig. 7 A and B are The light distribution pattern diagrams, FIGS. 8 to 11 show a second embodiment of the vehicle headlamp of the present invention, in which FIG. 8 is a schematic perspective view, FIG. 9 is a schematic vertical sectional view, and FIG. 10 is a schematic perspective view.
11 is a schematic horizontal sectional view, FIG. 11 is a light distribution pattern diagram, FIGS. 12 and 13 are examples of conventional vehicle headlamps, FIG. 12 is a schematic vertical sectional view, and FIG. 13 is a schematic horizontal sectional view. is a light distribution pattern diagram. Explanation of symbols, 1...Vehicle headlight, 2 ₁ , 2 ₂ ...
...Reflector, 3 ₁ , 3 ₂ ... Reflective surface, 4 ... Light source, 6
... Light shielding body, 7 ... Light shielding edge, 10 ... Projection lens, f ₀ ... Light source arrangement area, f ₁ ... Light collection area, f ₂ ... Light collection area, f _c ... Focal area of projection lens , x-x...optical axis, 20...vehicle headlight, 21...reflector, 2
2... Reflection mirror, 23... Reflection surface, 24... Reflection surface, 26... Light source, 28... Light shielding body, 29... Light shielding edge, 30... Projection lens.

Claims (1)

[Claims] 1. Light from a light source is reflected by a reflecting mirror and focused on a light condensing area in front, and a light shielding edge of a light shielding body is positioned near the light converging area, so that the focal area is shaded. A vehicle headlamp that projects light from the light shielding body and its vicinity forward by a projection lens located close to a light shielding edge of the body, wherein the reflecting mirror has a common optical axis and a common light source. It is composed of a plurality of reflecting surfaces divided into upper and lower parts, and the light-converging area of the reflecting surface is near the light-blocking edge of the light-blocking body, and is positioned in front and behind the focal area of the projection lens. A vehicle headlamp characterized by: