JPH01220301A - Head lamp for vehicle - Google Patents

Abstract

PURPOSE:To highly maintain the utilization factor of the light from a light source by arranging the light source at the focal point of the first reflecting mirror almost linearly collecting the light from the focal point and providing the second reflecting mirror reflecting the light from the first reflecting mirror forward. CONSTITUTION:The first reflecting mirror 2 has nearly a ship shape, its inner face 3 serving as a reflecting face is formed into a parabola-ellipse composite face shape. The optical axis x1-x1 of this reflecting mirror 2 is inclined forward and downward as viewed from the side, its opening face 4 faces obliquely upward and backward, it is arranged so that its vertical cross section is shaped in an ellipse, a light source 5 is provided at the position of one focal point f1. The second reflecting mirror 7 has nearly a parabolic columnar reflecting face 8, it is formed into a slender rectangular shape in the right and left direction as viewed from the front and below, it has a focal point 9 extended in parallel with the reflecting face 8. The light incoming to the reflecting face 8 through the focal point 9 is reflected in the direction parallel with an optical axis x2-x2, i.e., the axis of the parabola. A control lens 10 is arranged at the outlet section of the light from the light source 5 in front of a head lamp 1 for a vehicle, the preset light control action is performed by its slender shape, the light can be efficiently utilized.

Description

[Detailed description of the invention] The vehicle headlamp of the present invention will be explained according to the following items.

A. Industrial field of application B9 Summary of the invention C0 Background technology 1 Problems to be solved by the invention [Figure 13] E1 Means for solving the problems F. Examples [Figures 1 to 12 ] F-1, First embodiment [Figs. 1 to 4] a. First reflecting mirror, light source [Figs. 1 to 3] b. Second reflecting mirror, control lens [first Figures to Figures 3] C0 light distribution, luminous flux utilization efficiency [Figures 1 to 4] F-2, Second embodiment [Figures 5 to 8] F-3, Third embodiment [Figures 5 to 8] FIGS. 9 to 12 G1 Effects of the invention (A. Field of industrial application) The present invention relates to a novel headlamp for a vehicle. Specifically, the present invention aims to provide a novel headlamp for a vehicle in which the light exit from the light source has a narrow width while maintaining high utilization efficiency of the light from the light source.

(B. Summary of the Invention) The vehicle headlamp of the present invention condenses light from a light source into a line shape using a - reflector, and then breaks the basic pattern in which the light is condensed into a line shape. Instead, it is reflected forward by another reflecting mirror, thereby making it possible to maintain high utilization efficiency of the light from the light source even though the exit of the light from the light source is narrow. It is.

(C, Background Art) Modern vehicle headlamps are required not only to have excellent light distribution performance but also to have an excellent external design, especially the design of the front. One of them is the desire to increase the width.

In view of these demands, a headlamp a as shown in FIG. 13 was considered.

In the same figure, b is a reflecting mirror, and C is a reflecting surface of a reflecting utb, and this reflecting surface C has a shape similar to that of a paraboloid of revolution d with only the central part cut out in the direction orthogonal to the glaze x-x and the vertical direction. The secondary foot has a narrow shape in the left-right direction when viewed from the direction along the axis x-x. e is a light source placed at the focal point of the paraboloid of revolution d.

Therefore, according to such a headlamp a, the light emitted from the light source e and reflected by the reflecting surface C of the reflecting mirror is directed along the axis X- of the reflecting mirror.
The light flux is approximately parallel to X, and since this light flux has a narrow pattern in the horizontal direction when viewed from the front, the exit of this light flux, that is, the lens attached to the opening of the reflecting mirror or in front of it. can have a narrow shape in the left-right direction.

(D. Problem to be solved by the invention) [Figure 13] However, according to such a headlight a, the reflective surface C itself that reflects the light emitted from the light source e toward the front is narrow. Therefore, there is a problem that the usable solid angle of the light flux from the light source e in the direction perpendicular to the axis x-x is extremely small, and therefore the efficiency of use of the light flux from the light source is extremely low.

(E. Means for Solving the Problems) Therefore, in order to solve the above problems, the vehicle headlamp of the present invention uses a first reflection method that reflects the light from the focal point and condenses it in a line shape. A mirror, a light source disposed at or near the focal point, and a second reflecting mirror having a parabolic columnar reflecting surface and reflecting the light coming from the first reflecting mirror forward; , a light source is placed at or near the focal point of the first reflecting mirror.

Therefore, according to the vehicle headlamp of the present invention, the light from the light source is made into a linear beam in the optical path between the first reflecting mirror and the second reflecting mirror. The shape of the exit of the light reflected by the front part, that is, the front part of the headlamp can be narrowed, and the shape of the reflecting surface of the first reflecting mirror matches the shape of the front part. There is no need for the light source to be reflected in any shape as long as it has the function of condensing the light from the light source into a linear shape, so it is permissible to use any shape that reflects the light as completely as possible. Therefore, the use of light from the light source It is possible to maintain high efficiency.

(F. Embodiment) [FIGS. 1 to 12] Details of the vehicle headlamp of the present invention will be described below according to the illustrated embodiments.

(F-1, First Embodiment) [Figs. 1 to 4] Figs. 1 to 4 show a first embodiment 1 of the vehicle headlamp of the present invention.

(a, first reflecting mirror, light source) [Figures 1 to 3] 2 is the first reflecting mirror, which is approximately boat-shaped, and the inner surface 3, which is the reflecting surface, has a parabolic-elliptical compound surface shape. doing.

Here, the parabola-ellipse composite surface is a parabola in the - section perpendicular to the aperture surface 4 of the reflection fi2, and an ellipse in another cross section perpendicular to the aperture surface 4 and orthogonal to the above-mentioned - section. It refers to the one in which the focus of the parabola and the first focus of the ellipse coincide.

The reflecting mirror 2 is arranged such that its optical axis xt-Xl is inclined downward when viewed from the side, and its opening surface 4 faces diagonally upward and rearward, and its vertical cross section forms an ellipse. There is.

5 is the reflecting mirror 2 out of the two focal points that the ellipse of the reflecting surface 3 has.
One focal point f, located inside (hereinafter referred to as "first focal point")
Say. ) is a light source placed at

Therefore, the light λ,2 emitted from the light source 5 and reflected by the reflecting surface 3
, . . . are the reflecting surfaces 3 when looking at the reflecting mirror 2 in a vertical section.
Of the two foci that the ellipse has due to the elliptical element, the other focus fz (hereinafter referred to as
It's called "secondary focus." ), and is reflected by the parabolic element of the reflecting surface 3 in a direction parallel to the optical axes x, -x, so that a straight line 6 (hereinafter referred to as (referred to as the "concentration area").

(b. Second reflecting mirror, control lens) [FIGS. 1 to 3] The core is a second reflecting mirror having a reflecting surface 8 in the shape of a substantially parabolic column.

The reflecting surface 8 has a substantially rectangular shape elongated in the left-right direction when viewed from the front and from below, and is formed so that its entire area forms part of a parabola with a vertical cross section parallel to the front-rear direction. 9
is a focal line that passes through the focal point of the parabola and extends parallel to the reflecting surface 8.

Therefore, in the cross section perpendicular to the focal line 9, the light that has passed through the focal line 9 and is incident on the reflective surface 8 is reflected by the optical axis X2 of the reflective surface 8.
It will be reflected in a direction parallel to X2, that is, the axis of the parabola.

The second reflecting mirror 7 is located diagonally above and behind the first reflecting mirror 2, and its tip axis x2-x2 extends along the front-rear direction, and the focal line 9 is located at a position diagonally above and behind the first reflecting mirror 2. It is arranged in a state that substantially coincides with the light condensing area 6.

Reference numeral 10 denotes a control lens disposed at the front part of the vehicle headlamp 1, that is, at the exit part of the light from the light source 5. The control lens 10 is located in front of the second reflecting mirror 7 and has a narrow shape in the left-right direction. and
A lens step is formed that exhibits a predetermined light control effect.

(c. Light distribution, luminous flux utilization efficiency) [Figures 1 to 4] However, the light 1, l, . . . emitted from the light source 5 and reflected by the reflective surface 3 of the first reflecting mirror 2 is After condensing in a line shape in the left and right direction on the condensing area 6 of the first reflection t2, the light is diffused in the downward direction and becomes an elongated light beam in the left and right direction, and then the light beam is elongated in the left and right direction and sent to the second reflecting mirror 7.
At the same time, the light beam becomes incident on the reflective surface 8 of FIG. Therefore, the light emitted from the light source 5, λ, .

Then, the irradiation direction is controlled by the control lens 10 and the light is irradiated forward, thereby forming a light distribution pattern 11 as shown in FIG.

In addition, in FIG. 4 and other light distribution pattern diagrams, H-
The H line is the optical axis x2 of the second reflector 7 in front of the headlight.
It is a horizontal line that is orthogonal to -x2, and the V-V line is also a vertical line that is orthogonal to optical axes x and -X2.

Therefore, almost all of the light emitted from the light source 5 is emitted from the headlamp 1, so the utilization efficiency of the luminous flux from the light source 5 is extremely high. Since the light beam is converted into a narrow beam in the left and right direction by the reflector 7 of No. 2 and reaches the front part of the headlamp 1, the front shape of the headlamp can be made narrow while maintaining high utilization efficiency of light from the light source. be able to.

(F-2, Second Embodiment) [Figs. 5 to 8] Figs. 5 to 8 show a second embodiment 12 of the vehicle headlamp of the present invention.

The vehicle headlamp 12 shown in this second embodiment is different from the vehicle headlamp 1 shown in the first embodiment in that The only difference is the structure of the reflecting mirror and the provision of means for blocking part of the light. Therefore, the structure will be explained only with respect to the above-mentioned differences, and the explanation of other points will be omitted by assigning the same reference numerals to the same parts in the first embodiment. The usage of such symbols is the same in the third embodiment described later.

Reference numeral 13 denotes a first reflecting mirror, which is approximately boat-shaped, and its inner surface 14, which is a reflecting surface, has a hyperbolic-elliptical compound surface shape.

Here, the hyperbolic-elliptic compound surface is a hyperbola in the cross section of - perpendicular to the aperture surface 15 of the reflecting mirror 13, and the aperture surface 1
The other cross section perpendicular to 5 and orthogonal to the above-mentioned cross section is an ellipse, and the focal point of the hyperbola coincides with the first focal point of the ellipse.

The first reflecting mirror 13 has an optical axis X5-N3 extending along a downwardly inclined direction when viewed from the side, an opening surface 15 facing diagonally backward on the road, and an elliptical vertical cross section. It is oriented in such a way that it

16 is one focal point ts (
Hereinafter, it is a light source placed at the "first focal point"), and therefore, the light 11.11 s ... that exits from the light source 16 and enters the reflective surface 14 crosses the reflective mirror 13 in a vertical cross section. The light is reflected by the elliptical element of the reflective surface 14 to be focused on the other focal point f4 (hereinafter referred to as "second focal point") of the ellipse, and the hyperbolic element of the reflective surface 14 Since the light is reflected in a direction that becomes farther away from the optical axis x3-Xs as it goes to The light is collected in a state where it has diffusivity in the left and right directions.

The focal line 9 of the second reflecting mirror 7 is located at the condensing area 17.
It is arranged in a state that almost matches the .

Therefore, the light 11 , Juls . . . emitted from the light source 16 and reflected by the first reflecting mirror 13 is the first reflection! 1
After condensing in the condensing area 1 of i13, the light enters the reflecting surface 8 of the second reflecting mirror 7 while being diffused in the vertical and horizontal directions.
The light is substantially parallel to the optical axis x2-x2, and is diffused in the left-right direction and reflected forward.

Reference numeral 18 denotes a light-shielding plate that is long in the left-right direction and is disposed at a position slightly closer to the first reflecting mirror 13 from the light-converging area 1 of the first reflecting mirror 13, and its light-shielding edge 18a is located near the first reflecting mirror 13. It is located so as to be close to the optical axis X5-Xs of No. 13 from below and diagonally from the rear side.

Therefore, the light 121 reflected by the first reflecting mirror 13
% 111% exists as a cluster of light having a certain size at the position where the light shielding plate 18 is placed, and the lower part of the bundle of light is directed toward the N2 reflecting mirror 7 side by the light shielding plate 18. Since the light is blocked by the light beam, only the portion above it enters the second reflecting mirror 7 and is reflected forward, thereby forming the light distribution pattern 19 shown in FIG. 8.

(F-3, Third Embodiment) [Figs. 9 to 12] Figs. 9 to 12 show a third embodiment 2o of the vehicle headlamp of the present invention.

Incidentally, the vehicle headlamp 20 shown in this third embodiment is
The difference from the vehicle headlamp 1 shown in Embodiment 1 is that the structure of the first reflecting mirror reflects the light from the light source and focuses it into a line, and the provision of a means for blocking part of the light. This is the only point.

21 is a first reflecting mirror, which is also approximately boat-shaped.

Reference numeral 22 denotes an inner surface serving as a reflecting surface of the first reflecting mirror 21, and the reflecting surface 22 has a compound elliptical shape.

Here, the compound ellipsoid means the optical axis x4− of the reflecting mirror 22.
The - cross section parallel to x4 and the other cross section perpendicular to the - cross section and parallel to the optical axis The distance between the two foci f6 and fa that one 22a of the two ellipses 22a and 22b has is the same as that of the other ellipse 22a.
The first focus f of one ellipse 22a and the first focus f7 of the other ellipse 22b match, and the distance between the two foci f2 and fB of the reflecting mirror 21
is arranged so that its optical axis x4-x4 extends along a direction inclined downward when viewed from the side, its opening surface 23 faces upward and diagonally to the rear, and its vertical cross section forms the other ellipse 22b. ing.

f is the point where the first focal point f5 of one of the ellipses 22a and the first focal point f of the other ellipse 22b overlap (hereinafter referred to as "common first focal point"); 1 focal point f
. A light source 24 is arranged at.

Further, the reflective surface 22 allows the light from the common first focal point f0 to pass through the second focal point f6 of the one ellipse 22a and intersect with the optical axes x and -x4 in the direction below the road by the elements of one ellipse 22a. The beam is focused onto a focal line 25 (see FIG. 10) extending in an elliptical shape, and the element of the other ellipse 22b passes through the second focal point f8 of the other ellipse 22b and intersects the optical axis x4-x4 approximately horizontally. It has a shape that focuses light onto a focal line 26 (see FIG. 11) extending in an elliptical shape.

Incidentally, a method for obtaining the reflecting surface 22 having such light condensing characteristics is shown in, for example, Japanese Patent Application No. 62-68260.

Therefore, the luminous flux of the light L2, β2, . . . emitted from the light source 24 and reflected by the first reflecting mirror 13 is
The ellipse condenses light in an elliptic curve shape extending in the left-right direction at the focal line 26, which is the focal area of the light condensing area of b, and spreads in the vertical direction from there, and extends downward on the road at the focal line 25, which is the focal area of one ellipse 22a. The light is focused in a curved shape, and from there it spreads out in the left and right directions.

The focal line 9 of the second reflecting mirror 7 is the same as that of the first reflecting mirror 1.
The second ellipse 22b of No. 3 is arranged to extend in the left-right direction through the second focal point f8 of the other ellipse 22b.

Reference numeral 27 denotes a light shielding plate, which is long in the left-right direction and has the focal line 26 when viewed from a direction intersecting its thickness direction and longitudinal direction.
The light shielding edge 28 is formed in a curved shape substantially corresponding to the shape of the light shielding edge 28, and approximately half of the light shielding edge 28, which is one side edge in the width direction, approaches the side edge opposite to the light shielding edge 28 as it goes to one end in the longitudinal direction. The light-shielding edge 28
The approximately central portion 28a of the reflective surface 22 of the first reflective mirror 21 is arranged so that it approaches a position slightly closer to the first reflective mirror 21 side than the second focal point f6 of the other ellipse 22b of the reflective surface 22 of the first reflective mirror 21 from the lower diagonal rear side. has been done.

Therefore, the luminous flux of the light J22, I12, . . . emitted from the light source 24 and reflected by the first reflecting mirror 21 is
7 exists as a group of elongated lights in the left and right direction, and the lower part of the group of light is the light shielding plate 27.
is blocked from the second reflecting mirror 7 side, and only the upper part enters the reflecting surface 8 of the second reflecting mirror 7, where it is reflected forward. When,
The above light is directed upward and downward through the optical axis x2-x2 of the second reflecting mirror 7.
In the horizontal direction, the light is focused at the -H light focusing area f6' and then diffused.

Reference numeral 29 denotes a projection lens in the shape of a convex lens disposed in front of the second reflecting mirror 7, and its focal point is located near the center portion 28a of the light-shielding edge 28 of the light-shielding plate 27.

Thus, the light from the light source 24 forms a light distribution pattern 30 shown in FIG. That is, the bundle of reflected lights J22, J22, . , whereby a light distribution pattern 30 is obtained.

(G. Effects of the Invention) As is clear from the above description, the vehicle headlamp of the present invention includes a first reflecting mirror that reflects light from a focal point and condenses it in a line, and A light source disposed at or near the light source, and a second reflecting mirror having a parabolic columnar reflecting surface and reflecting the light coming from the first reflecting mirror forward. .

Therefore, according to the present invention, the light from the light source is made into a linear beam in the optical path between the first reflecting mirror and the second reflecting mirror, so that the light reflected by the second reflecting mirror The shape of the outlet, that is, the front part of the headlamp can be made narrow, and the shape of the reflecting surface of the first reflecting mirror does not need to match the shape of the front part. Therefore, as long as it has the function of condensing the light from the light source into a linear shape, it is allowed to have any shape that reflects the light as completely as possible.

Therefore, according to the present invention, it is possible to maintain high utilization efficiency of the light from the light source even though the exit of the light from the light source is narrow, and moreover, the first reflecting mirror can be connected to the second reflecting mirror. Since it can be placed above or below the road, the depth dimension can be reduced.

In each of the above embodiments, the first reflecting mirror has a parabolic-elliptic compound surface, a hyperbolic-elliptical compound surface, and a compound elliptical reflecting surface. However, the first method in the present invention
The reflecting mirror is not limited to one having such a reflecting surface, and may have any shape as long as it can condense the light from the light source into a linear shape.

Furthermore, in each of the above embodiments, the focal line of the parabolic reflection surface of the second reflection mirror was made to coincide with the light condensing area of the first reflection mirror. The optical positional relationship with the reflecting mirror is not particularly limited except that the light from the first reflecting mirror is reflected forward.

[Brief explanation of the drawing]

1 to 4 show a first embodiment of the vehicle headlamp of the present invention, in which FIG. 1 is a vertical sectional view, FIG. 2 is a perspective view,
FIG. 3 is a sectional view taken along the line III--III in FIG. 1, FIG. 4 is a light distribution pattern diagram, and FIGS. 5 to 8 show a second embodiment of the vehicle headlamp of the present invention. 5 is a perspective view, FIG. 6 is a vertical sectional view, FIG. 7 is a sectional view taken along the line ■-■ in FIG. 6, FIG. 8 is a light distribution pattern diagram, and FIGS.
The figure shows a third embodiment of the vehicle headlamp of the present invention.
Fig. 9 is a perspective view, Fig. 10 is a vertical sectional view, Fig. 11 is a sectional view along the cutting blade line in Fig. 10, Fig. 12 is a light distribution pattern diagram, and Fig. 13 is a conventional vehicle front view. It is a schematic perspective view showing an example of a lighting lamp. Explanation of symbols 1... Vehicle headlight, 2... First reflecting mirror, 5... Light source, 7... Second reflecting mirror, 8... Reflecting surface, fl... focus,
12... Vehicle headlight, 13... First reflector,
16... Light source, f3... Focus, 20... Vehicle headlight, 21... First reflecting mirror, 24...
Light source, fo... Perspective view of Koito Manufacturing Co., Ltd. Figure 3 Figure 4 Perspective view 17I (second embodiment) Figure 5 N! Example of lI vertical section 2, w Fig. 6 Fig. 7 Fig. 8 Perspective view (third embodiment) Fig. 9 N ■ Vertical section 1fiL4 (third embodiment) Fig. 10 x4 Cross-sectional view Figure 11 Light distribution pattern L'il (Example of $3) Figure 12

Claims (1)

[Claims] a first reflecting mirror that reflects the light from the focal point and focuses it in a linear shape; a light source disposed at or near the focal point;
A vehicle headlamp characterized by comprising a second reflecting mirror having a parabolic columnar reflecting surface and reflecting light coming from the first reflecting mirror toward the front.