JPH04124703U - vehicle headlights - Google Patents

Abstract

(57) [Summary] [Purpose] Improve headlights with large slant angles to diffuse stray light generated by reflection from the front lens and bottom of the lamp housing in the vertical direction so as not to dazzle oncoming vehicles. do. [Structure] The vicinity of the front end of the bottom surface 4b of the lamp housing 4 is curved downward to form a curved surface that is convex upward. The reflected lights c, c'', c' from the front lens 2 are reflected by the convex curved surface and are diffused in the vertical direction as e, e'', e'.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention features a slant-shaped front lens that covers the front opening of the lamp housing. This relates to the vehicle headlights that are installed.

0002

[Conventional technology]

Modern vehicles, especially passenger cars, are designed not only for mechanical performance but also for aesthetic value. In pursuit of improvements, slant-type headlights are often used.

0003 A slant-type headlamp covers the front opening of the lamp housing and A lens is attached. Here, a slant is a shape that has a slope compared to the vertical surface. In general, it intersects the vertical plane with a substantially horizontal line, and the lower part of the lens surface is the direction of light emission. It protrudes in the opposite direction.

0004 Figure 3 shows a vehicle headlight with a slant-type front lens 2 attached to a lamp housing 1. FIG. 2 is a vertical cross-sectional view showing a conventional example of a lamp.

[0005] The inner surface of the lamp housing 1 is plated with metal to form a reflective surface.

[0006] The back surface 1a is formed into a paraboloid of revolution, Z is its optical axis, and F is its focal point.

[0007] A light source (not shown) is installed near the focal point F, and the light is emitted from the light source in the direction of arrows a and a'. The light beam incident on the parabolic reflection surface 1a is parallel to the optical axis Z as shown by arrows b and b'. reflected in the line.

[0008]

[Problem that the idea aims to solve]

A vertical line h passing through the point where the optical axis Z intersects the front lens 2 is assumed. θ is slant It is a corner.

[0009] When the slant angle θ is relatively large (for example, 45° or more) as in this conventional example, A part of the light beam incident on the front lens 2 is reflected by the front lens 2 as shown by arrows b and b'. and enters the vicinity of the front end of the lamp housing bottom surface 1b as shown by arrows c and c'. The light is then reflected diagonally upward toward the front of the lamp as shown by arrows d and d'.

0010 This type of glare (stray light) directed upward and forward is undesirable because it dazzles oncoming vehicles. It is legal and regulated.

[0011] In order to prevent or reduce the above glare, the optical axis Z is Although attempts have been made to provide cylindrical surface (or elliptical cylindrical surface) unevenness parallel to the , as seen in Fig. 4(B), the light distribution zone 3 of the stray light (arrows d, d') is moved left and right. Although it is possible to diffuse the light in different directions, the anti-dazzle effect is not perfect.

0012 This figure 4 (B) shows how to level the optical axis Z of the headlight and illuminate a vertical screen. This is a light distribution characteristic chart showing the state in which H-H' is the horizontal line on the screen, and V is the horizontal line on the screen. -V' is also a vertical line.

[0013] This invention was created in view of the above circumstances, and is suitable for slant-type headlamps. This effectively eliminates stray light that is reflected by the front lens and the bottom of the lamp housing. The purpose is to completely diffuse the light and eliminate the risk of dazzling oncoming vehicles.

[0014]

[Means to solve the problem]

The vehicle headlight according to the present invention has a structure for achieving the above object. The bottom of the housing is curved downward near the front end.

[0015] A bottom surface that is curved downward inevitably forms a curved surface that is convex upward. Ru.

[0016]

[Effect]

The lamp housing configured as described above is located near the front end of the bottom surface of the lamp housing. The part where the reflected light from the slanted front lens enters has a convex curved surface. Diffuses incident light vertically. This allows stray light to be sufficiently diffused to dazzle oncoming vehicles. There is no risk of confusion.

[0017]

【Example】

FIG. 1 shows one embodiment of a vehicle headlamp according to the present invention, and is a schematic vertical cross section. It is a diagram.

[0018] This embodiment is an improvement by applying the present invention to the conventional example shown in FIG. The front lens 2 with the same drawing reference number as in FIG. 3 is the same as in the conventional example. Similar components. 4 is a lamp housing constructed by applying the present invention. A reflective coating is provided on its inner surface.

[0019] The back surface 4a of the lamp housing is configured in the shape of a paraboloid of revolution, and has a focal point F. The light fluxes of arrows a, a″, and a′ emitted from the Reflect on the line.

[0020] The above reflected light beams b, b'', b' are reflected by the arrows c, It is reflected as c'', c'.

[0021] Therefore, the bottom surface 4b of the lamp housing of this embodiment is located near its front end, that is, The area where the reflected lights c, c'', c' are incident is curved downward and convex upward. It constitutes a curved surface.

[0022] Therefore, the luminous flux reflected by this convex curved surface is directed upward and downward as shown by the arrows e, e'', and e'. spread to.

[0023] FIG. 2 is a light distribution characteristic chart for explaining the functions and effects of the above embodiment.

[0024] 3 in the diagram is drawn for comparison reference, and is similar to FIG. 4(B) in the conventional example. Light distribution zone 3 has been transcribed.

[0025] In the vehicle headlight of this embodiment (Fig. 1), the reflected lights e, e'', and e', which become stray lights, are As shown in Fig. 2, the light distribution zone 3 of the conventional example is further expanded in the vertical direction. The light is dispersed to form a light distribution zone 5 shown in the figure.

[0026] In the conventional example, stray light was concentrated in a relatively narrow light distribution zone 3, but in this example, stray light is concentrated in a relatively narrow light distribution zone 3. Since the light is diffused into a wide light distribution zone 5, there is no risk of dazzling oncoming vehicles.

[0027]

[Effect of the idea]

By applying this invention to a slant-type headlamp, the front end of the bottom of the lamp housing is attached. By curving the near part downward and forming a reflective surface that is convex upward, the front lens will reflect. The light that enters the bottom of the lamp housing is diffused and reflected in the vertical direction. There is no risk of dazzling oncoming vehicles.

[Brief explanation of drawings]

[Fig. 1] A schematic vertical sectional view showing one embodiment of a vehicle headlamp according to the present invention.

[Figure 2] Light distribution characteristic chart for explaining the function and effect of the above embodiment

[Fig. 3] A schematic vertical cross-sectional view showing a conventional vehicle headlamp.

[Fig. 4] Explanatory diagram of technical problems in the above conventional example

[Explanation of symbols]

1... Lamp housing, 1a... Parabolic reflection surface, 1b...
Bottom surface, 2... Front lens, 3... Conventional light distribution zone, 4...
Lamp housing, 4a... Parabolic reflection surface, 4b... Bottom surface, 5... Light distribution zone of the example, a, a', a''... Optical path emitted from the light source, b, b', b''... Parabolic reflection Optical path of light reflected by the surface, c, c', c''... Optical path reflected by the front lens, d, d', d''... Optical path reflected by the bottom of the conventional lamp housing, e, e', e''... Implementation Optical path reflected from the bottom of the lamp housing in the example, F...focal point, h...imaginary vertical line, H...horizontal line on the screen, V... vertical line on the screen, Z...optical axis, θ...slant angle

Claims (1)

[Scope of utility model registration request] 1. A vehicle headlamp equipped with a slant-shaped front lens covering a front opening of a lamp housing, characterized in that a front end portion of a bottom surface of the lamp housing is curved downward. headlights.