JP2542910B2 - Automotive headlights - Google Patents

Description

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

A. Industrial fields of use B. Overview of the invention C. Prior art [Fig. 6] D. Problems to be solved by the invention [Fig. 6] E. Means for solving the problems F. 1 to 5] a. Reflecting mirror b. Light source c. Lens G. Effect of the invention (A. Field of industrial application) The present invention relates to a novel automotive headlamp. For more information,
The present invention relates to an automobile headlamp having two light sources for a traveling beam and a passing beam, which can illuminate a far distance well when a traveling beam is radiated and also illuminates a nearby road surface well, thus providing a vast area. The present invention aims to provide a new vehicle headlight that enables a traveling beam to be used like a passing beam when traveling at high speed.

(B. Summary of the Invention) The headlight for an automobile of the present invention has two reflecting surfaces on the upper side and the lower side, and each of the two reflecting surfaces has a shape in which a paraboloid of revolution is roughly cut up and down. The optical axes of these reflecting surfaces are vertically shifted, the focal length of the upper reflecting surface is made larger than that of the lower reflecting surface, and the focal points of the upper reflecting surface and the lower reflecting surface are substantially the same when viewed from above. In addition, the light source is composed of a traveling beam filament extending substantially parallel to the optical axis of the reflecting surface and a low beam filament positioned in front of the traveling beam filament. Is placed on the optical axis of the upper reflection surface and near the focal point of the lower reflection surface, and the filament for the low beam is placed substantially on the optical axis of the upper reflection surface and in front of the focal point of the upper reflection surface. Contralateral The direct light of the first light shielding means and two filaments that shields against the surface from being irradiated forward 2
This means that the light reflected by the upper reflecting surface of the light from the light source for the traveling beam is emitted to a far distance, and the light reflected by the lower reflecting surface is emitted to a relatively near side. However, while traveling in a vast area at high speed, by using the traveling beam, not only the distance visibility but also so-called foot visibility can be improved, and the traveling beam can also be used as a passing beam when traveling at high speed.

(C. Prior art) [Fig. 6] There is a conventional vehicle headlamp equipped with a single rotating parabolic reflector, two light sources, and a lens.

 FIG. 6 shows an example a of such a vehicle headlamp.

Reference numeral b is a reflecting mirror, which has a reflecting surface c in the shape of a paraboloid of revolution, and xx is its rotation axis, which is called the optical axis. Further, F is the focus of the reflecting surface c.

Reference numeral d denotes a traveling beam filament, which is in the shape of a coil and is arranged at a substantially focal point F position of the reflecting surface c and substantially parallel to the optical axis xx. Reference numeral e is a coiling filament for a low beam, which is arranged in front of the focal point F along the optical axis xx.

Reference numeral f denotes a light-shielding cap, which is arranged so as to shield substantially the lower half of the passing beam filament e from the reflecting surface c. Although not shown, a light-shielding means is provided in addition to the light-shielding cap f so that the direct light of the filaments d and e is not emitted forward.

Reference numeral g denotes a lens arranged on the front side of the reflecting mirror b, on which a required lens element (not shown) is formed.

Then, in the above-mentioned automobile headlamp a, the light of the traveling beam filament d is reflected by the reflection surface c to become a light beam substantially parallel to the optical axis xx, and the light beam of the low beam filament e. The light is reflected by substantially the upper half of the reflecting surface c to become a light flux slightly downward with respect to the optical axis xx, and is irradiated with a predetermined light distribution pattern controlled by the lens elements of the lens g.

(D. Problem to be Solved by the Invention) [FIG. 6] By the way, in the above-mentioned conventional vehicle headlamp a, the front side, for example, a portion from 20 m in front to the front is sufficiently sufficient when the traveling beam is irradiated. There is a problem that it is not possible to irradiate.

For example, when traveling in an area with a vast spread such as Australia, a traveling beam is often used, and therefore a characteristic of a passing beam is required for the traveling beam. That is, it is required to be able to sufficiently irradiate a distant place and at the same time to illuminate the near side.

Then, in the case of a rotating parabolic reflecting surface, if the focal length of the parabolic surface is increased, the reflected light of the filament arranged at that focal point is collected in a small range around the optical axis xx, and that much. Although the light reaching far distances increases, the distance visibility is improved, but on the other hand, the light directed toward the front is reduced and the front visibility deteriorates.

On the contrary, when the focal length of the parabolic surface is reduced, the reflected light of the filament arranged at that focal position has the same optical axis x− as compared with the case where the focal length is large even if the amount of deviation from the focus is the same.
Since the deviation amount of the parallelism with respect to x becomes large, the divergence angle of the luminous flux of the reflected light becomes large as compared with the case where the focal length is large, and therefore, it becomes possible to sufficiently turn the light to the near side. However, the larger divergence angle of the reflected light with respect to the optical axis xx means that the light flux density at the central portion becomes sparser than that when the focal length is large, and the number of light fluxes reaching farther decreases accordingly. However, there is a problem that the distance visibility is deteriorated and the function as a traveling beam cannot be sufficiently achieved.

(E. Means for Solving the Problem) In order to solve the above-mentioned problems, the vehicle headlamp of the present invention has two reflecting surfaces on the upper side and the lower side, and the two reflecting surfaces are respectively rotated. The parabolic surface has a shape that is roughly divided into upper and lower parts, and the optical axes of these reflecting surfaces are vertically shifted, and the focal length of the upper reflecting surface is made larger than that of the lower reflecting surface, and The focal point and the focal point of the lower reflecting surface should be at approximately the same position when viewed from above.Furthermore, the light source should be a traveling beam filament that extends substantially parallel to the optical axis of the reflecting surface, and a passing beam located in front of the traveling beam filament. The traveling beam filament is arranged substantially on the optical axis of the lower reflecting surface and near the focal point of the lower reflecting surface, and the passing beam filament is arranged on the upper reflecting surface of the upper optical surface. Before focus Provided with a first light blocking means for blocking the light of the low beam filament toward the lower reflection surface and a second light blocking means for preventing the direct light of the two filaments from being irradiated forward. Is.

Therefore, in the vehicle headlight of the present invention, of the light of the light source for the traveling beam, the light reflected by the upper reflecting surface is radiated to a distance and contributes to the distance visibility, and is reflected by the lower reflecting surface. Since the reflected light has a relatively large spread with respect to the optical axis, it irradiates a relatively near side, and while traveling at high speed in a vast area, by using the traveling beam, it is possible to see at a distance as well as the visibility of the feet. Also, it is possible to use the traveling beam as a passing beam when traveling at high speed.

(F. Embodiment) [FIGS. 1 to 5] Hereinafter, details of a vehicle headlamp according to the present invention will be described according to a first embodiment.

(A. Reflecting mirror) 2 is a reflecting mirror, and is provided with an upper reflecting surface 3 and a lower reflecting surface 4. The upper reflecting surface 3 is shaped like leaving the upper half of the paraboloid of revolution, and the lower reflecting surface 4 is shaped like leaving the lower half of the paraboloid of revolution.

Further, in this embodiment, the upper reflecting surface 3 is a fan-shaped portion 3a which extends slightly downward on the left side.
And the lower reflection surface 4 is correspondingly smaller. The fan-shaped portion 3a is about 15 with the center of the reflecting mirror 2 as the center.
It is a fan-shaped part at the central angle of °. It should be noted that this is adapted to the left-hand traffic of the vehicle, and in the case of the right-hand traffic of the vehicle, the fan-shaped portion is formed on the right side.

The optical axes of the two reflecting surfaces 3 and 4 (corresponding to the rotational axes of the paraboloids of rotation) x ₁ −x ₁ and x ₂ −x ₂ are parallel to each other, and there is a slight vertical gap. The optical axis x ₁ -x ₁ of the upper reflecting surface 3 is located above the optical axis x ₂ -x ₂ of the lower reflecting surface 4 by the shift of t.

The focal lengths F ₁ of the upper reflecting surface 3 and the focal lengths F ₂ of the lower reflecting surface 4 are larger than the focal length F ₂ of the lower reflecting surface 4 and the focal lengths f of the both reflecting surfaces 3 and 4 are the same. ₁ and f ₂ are located at approximately the same point on the plane.

Reference numeral 5 is an insertion hole formed in the center of the reflecting mirror 2, and the radius of the lower half 5b is smaller than the radius of the upper half 5a.

(B. Light source) 6 is a light source, and in this embodiment, a so-called European standard
H4 type is used.

The light bulb 6 includes a glass bulb 7, a base 8 attached to the rear end of the glass bulb 7, two filaments 9 and 10 enclosed in the glass bulb 7, and a light-shielding cap that covers approximately the lower half of one filament 10. 11 and the light-shielding paint 12 is attached to the front end of the glass ball 7. The two filaments 9 and 10 each have a coil shape, and the glass sphere 7
The filament 10 is arranged so as to extend along the axis of, and the filament 10 is arranged in front of the filament 9.

Such a light bulb 6 is attached to the reflecting mirror 2 by a suitable means (not shown), and its glass bulb 7 is placed in the reflecting mirror 2 through the insertion hole 5. The filament 9 is a filament for the traveling beam, and the focal point of the lower reflection surface 4 is
The filament 10 is arranged at the f ₂ position along the optical axis x ₂ −x ₂ of the lower reflecting surface 4, and the filament 10 is a filament for a low beam, and along the optical axis x ₁ −x ₁ of the upper reflecting surface 3. Further, it is arranged in front of the focal point f ₁ of the upper reflecting surface 3.

Then, the light-shielding cap 11 shields the low-beam filament 10 from the lower reflecting surface 4, so that the light of the low-beam filament 10 is reflected by the upper reflecting surface 3 (including the fan-shaped portion 3a). Only the emitted light is emitted forward.

The light-shielding paint 12 formed on the front end of the glass bulb 7 of the light bulb 6 shields the filaments 9 and 10 from the front, so that the light from the filaments 9 and 10 is reflected by the reflecting mirror 2. Only things are illuminated forward.

Thus, in the above structure, the light emitted from the filaments 9 and 10 and reflected by the reflecting mirror 2 is irradiated in a pattern as shown in FIG. In FIG. 5, H-H
Is the horizontal line in front of the headlight and across the height of the headlight, V-V
Is a vertical line passing through the point corresponding to the center of the headlight in front of the headlight.

Since the passing beam filament 10 is shielded from the lower reflecting surface 4 by the light-shielding cap 11, only the light reflected by the upper reflecting surface 3 is radiated forward to the pattern 13 shown in FIG. Indicates. This pattern 13
Of the left side of the V-V line above the H-H line
Reference numeral 13a denotes a pattern formed by the light reflected by the fan-shaped portion 3a of the upper reflecting surface 3, and when the fan-shaped portion 3a is located on the right side, the portion 13a can be formed on the right side of the line V-V.

The light emitted from the traveling beam filament 9 is reflected by the reflecting surface 3,
4 shows the pattern 14 reflected by FIG. Of the patterns 14, 15 is a portion formed by the light reflected by the upper reflecting surface 3, and 16 is a portion formed by the light reflected by the lower reflecting surface 4.

As can be seen from FIG. 5B, the focal length F ₁ of the upper reflecting surface 3 is larger than the focal length F ₂ of the lower reflecting surface 4, so that the pattern 15 is a small pattern near the center. Therefore, the luminous flux density is high, and accordingly, a large amount of light is emitted relatively far. Further, since the focal length F ₂ of the lower reflecting surface 4 is made relatively small, the reflected light is reflected by the optical axis.
The divergence angle with respect to x ₂ −x ₂ is large and the luminous flux density is low, but the partial pattern 16 by this light improves the visibility in the front and side directions.

Incidentally, FIG. 5 shows a pattern formed only by the reflecting mirror 2, and these patterns 13 and 14 are controlled by a lens described later to form a desired light distribution pattern. As shown in FIG. 5 (B), the prototype pattern of the traveling beam has a pattern suitable for the distance visibility and the visibility of the feet, so that the control by the lens is easy and the desired light distribution is obtained. The pattern is obtained.

In order to achieve the above effects, the focal length F ₁ of the upper reflecting surface 3 is 25 mm to 35 mm and the focal length F ₂ of the lower reflecting surface 4 is F _2.
Is 15 mm to 25 mm, and the distance t between the optical axes x ₁ −x ₁ and x ₂ −x _{2 of them} is t
Is most preferably in the range 0.2 mm to 1.1 mm.

(C. Lens) 17 is a lens arranged in front of the reflecting mirror 2, and an appropriate lens element is formed to control the light reflected by the reflecting mirror 2.

(G. Effect of the Invention) As is clear from the above description, the vehicle headlamp of the present invention is provided with a reflector having an upper reflection surface and a lower reflection surface, two light sources and a front side of the reflection mirror. A headlamp for an automobile, comprising: an upper lens and a lower lens, the upper and lower reflecting surfaces of which are substantially parabolic shapes of a paraboloid of revolution and whose rotation axes (optical axes) are substantially parallel to each other. Extending in the front-back direction and the optical axis of the upper reflecting surface is located slightly above the optical axis of the lower reflecting surface,
Further, the focal length of the upper reflecting surface is larger than the focal length of the lower reflecting surface, and the focal point of the upper reflecting surface and the focal point of the lower reflecting surface are substantially at the same position when seen in a plane, and the light source is the optical axis of the reflecting surface. It consists of a traveling beam filament extending substantially in parallel with the traveling beam filament and a low beam filament located in front of the traveling beam filament.The traveling beam filament is approximately on the optical axis of the lower reflecting surface and near the focal point of the lower reflecting surface. In addition to being arranged, the passing beam filament is arranged substantially on the optical axis of the upper reflecting surface and in front of the focal point of the upper reflecting surface, and shields the light of the passing beam filament with respect to the lower reflecting surface. Means and a second light shielding means for preventing the direct light of the two filaments from being emitted forward are provided.

Therefore, in the vehicle headlight of the present invention, of the light of the light source for the traveling beam, the light reflected by the upper reflecting surface is radiated to a distance and contributes to the distance visibility, and is reflected by the lower reflecting surface. Since the shining light has a relatively large spread with respect to the optical axis, it irradiates a relatively near side, and while traveling at high speed in a vast area, by using the traveling beam, it is possible to see at a distance as well as the visibility of the feet. Also, it is possible to use the traveling beam as a passing beam when traveling at high speed.

[Brief description of drawings]

1 to 5 show an example of an embodiment of a vehicle headlamp according to the present invention. FIG. 1 is a longitudinal sectional view, FIG. 2 is a front view showing a lens without a lens, and FIG. 3 is a reflecting mirror. Front view, FIG. 4 is a schematic vertical sectional view for explaining the positional relationship of each part, FIG. 5 is a light distribution pattern diagram, and FIG. 6 is a schematic vertical sectional view showing an example of a conventional automotive headlamp. Is. DESCRIPTION OF SYMBOLS 1 ... Automotive headlight, 2 ... Reflecting mirror, 3 ... Upper reflecting surface, 4 ... Lower reflecting surface, 9 ... Running beam filament, 10 ... Dipped beam filament, 11 ...... First light shielding means, 12 ...... Second light shielding means, 17 ...... Lens, x ₁ −x ₁ …… Optical axis of upper reflecting surface, x ₂ −x ₂ …… Optical axis of lower reflecting surface , F ₁ ... focal point of upper reflecting surface, f ₂ ... focal point of lower reflecting surface, F ₁ ... focal length of upper reflecting surface, F ₂ ... focal length of lower reflecting surface

Claims (1)

(57) [Claims] 1. An automotive headlamp comprising a reflecting mirror having an upper reflecting surface and a lower reflecting surface, two light sources and a lens arranged in front of the reflecting mirror, wherein upper and lower reflecting surfaces are respectively provided. The paraboloid of revolution has a shape roughly halved up and down, and the rotation axes (optical axes) of the parabolic surfaces extend in the front-rear direction in parallel and the optical axis of the upper reflecting surface is slightly above the optical axis of the lower reflecting surface. Furthermore, the focal length of the upper reflecting surface is larger than that of the lower reflecting surface, and the focal point of the upper reflecting surface and the focal point of the lower reflecting surface are almost at the same position when seen in a plan view. It consists of a traveling beam filament extending substantially parallel to the optical axis of the surface and a low beam filament located in front of the traveling beam filament.The traveling beam filament is located approximately on the optical axis of the lower reflecting surface and on the lower reflecting surface. Is placed near the focal point of the The filament for light is arranged substantially on the optical axis of the upper reflecting surface and in front of the focal point of the upper reflecting surface, and has a first light blocking means for blocking the light of the low beam filament for the lower reflecting surface and two filaments. And a second light shielding means for preventing the direct light of the vehicle from being emitted forward.