JPS634323Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to an automobile headlamp.

[Conventional technology]

As shown in FIGS. 1 and 2, a conventional automobile headlamp includes a reflector 1 and a light source (bulb) 2 placed near the focal point of the reflector 1.
and a lens 3 disposed in front of the light source 2. A reflector 1 is provided on the inner surface of the lens 3.
A concave curved prism or a convex curved prism is formed to diffuse the reflected light from A large number of cylindrical prisms 4 are continuously formed.

In the lens 3 of such an automobile headlamp, the outer surfaces 5 at both left and right ends are naturally formed into convex curved surfaces. That is, in this conventional example, the central axis O of the concave cylindrical prism 4 located at the outermost position among the concave cylindrical prisms on the inner surface is the central axis, and the radius is the radius R of the concave cylindrical prism and the wall thickness t of the lens 3. A convex cylindrical surface 5 is formed.

[Problem that the invention attempts to solve]

A conventional vehicle headlamp lens having a concave cylindrical prism formed on its inner surface has the above-mentioned configuration, so that the lens 3 has transparent bent portions at both left and right ends, that is, a concave cylindrical prism 4 and a convex cylindrical surface 5. A transparent part is formed and the prism effect cannot be achieved, and the light L incident on both the left and right ends of the lens 3 passes through as it is, and when the vehicle is actually running, it cannot produce a prism effect.
Bright vertical stripes appear around 60 degrees, causing problems with light distribution characteristics. Further, since there are transparent portions at both left and right ends of the lens 3, there is a problem in that the interior of the headlamp can be seen through those portions.

The present invention aims to provide a vehicle headlight that uses a lens with a concave cylindrical prism formed on its inner surface, and which can improve the above-mentioned problems. .

[Means for solving problems]

In order to achieve the above object, the present invention is characterized in that a large number of concave cylindrical prisms are continuously formed on the inner surface of the lens, and the prisms at both left and right ends are convex cylindrical prisms.

[Effect]

In this invention, most of the prisms on the inner surface of the lens except for the left and right ends are concave cylindrical prisms, so the use of concave cylindrical prisms has the effect of saving materials. The lens has a prism effect due to the convex cylindrical surface on the outer surface and the convex cylindrical surface prism on the inner surface, and therefore, the light incident on both the left and right ends of the lens is greatly diffused to the left and right. Problems can be improved.

〔Example〕

Hereinafter, one embodiment of a vehicle headlamp according to the present invention will be described with reference to FIG. 4.

In the figure, the same reference numerals as in FIGS. 1 to 3 indicate the same parts.

Therefore, in the automobile headlamp of the present invention, a large number of concave cylindrical prisms 4 are continuously formed on the inner surface of the lens 3, and convex cylindrical prisms are formed at both left and right ends of the concave cylindrical prism 4, that is, the lens 3. An axis eccentric from the central axis O of the outer convex cylindrical surface 5 at both left and right ends of 3
A convex cylindrical prism 6 having a center axis O' and a radius R is formed. In other words, about two of the conventional concave cylindrical prisms 4 at both left and right ends (only the right end is shown in the drawing) are replaced with convex cylindrical prisms 6.

As described above, the automobile headlamp of the present invention has a convex cylindrical prism 6 on the left and right ends of the lens 3, which has a concave cylindrical prism on its inner surface. Having formed a prism,
There is also a prism effect at both ends, and as a result, the light that enters the left and right ends of the lens 3 is greatly diffused to the left and right, and transparent parts are formed at both the left and right ends of the lens 3, which brightens the area approximately 60 degrees ahead when the vehicle is actually running. It is possible to solve the problem of light distribution characteristics that causes vertical stripes. Furthermore, it is possible to solve the problem of the appearance of the internal structure of the headlamp being visible from the outside.

[Effect of idea]

As described above, although the automobile headlamp of the present invention has a concave cylindrical prism formed on the inner surface, no transparent part is formed at the end of the lens, and problems with light distribution characteristics can be solved. Appearance problems can be resolved.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a conventional automobile headlamp;
The figure is a view taken along the - line in FIG. 1, and FIG. 3 is an enlarged view of the portion in FIG. 1. FIG. 4 is a partial sectional view of the right end of the lens showing an embodiment of the automobile headlamp according to the present invention. 1... Reflector, 2... Light source, 3... Lens, 4... Concave cylindrical prism, 5... Convex cylindrical surface,
6...Convex cylindrical prism.

Claims (1)

[Scope of utility model registration request] In an automobile headlamp comprising a reflector, a light source disposed near the focal point of the reflector, and a lens disposed in front of the light source, a large number of concave cylindrical prisms are continuously formed on the inner surface of the lens, and , an automotive headlamp characterized in that the prisms at both left and right ends are convex cylindrical prisms.