JPS62202401A - Projector type head lamp - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a projector type vehicle headlamp.

[Conventional technology]

Automobile headlights must have a light distribution pattern that brightly illuminates the area in front of the vehicle's own lane and does not dazzle oncoming vehicles.

A projector-type automobile headlamp has been proposed as a headlamp that has light distribution characteristics that meet the above requirements, has a simple lens configuration, and can be made compact in overall size. As the latest technology regarding this projector type headlamp, for example, Japanese Patent Laid-Open No. 58-209801 is known.

FIG. 7 shows the above-mentioned known projector type headlamp. The headlight of this known example is provided with a shell-shaped reflector, and the axial cross section of the inner reflective surface of this reflector each forms a part of an ellipse, and the eccentricity of the ellipse is perpendicular to the axial direction. In a vehicle headlamp increasing from the longitudinal section towards the axially horizontal longitudinal section, the focal point 105 of the elliptical portions 101, 102 of all axial sections is also the elliptical portion 101 of all axial sections. The corresponding vertices 104 of .102 are configured to match.

110 is an outer focal point of the ellipse 102, 110 is a light-shielding plate-like dimmer, 112 is an outer focal point of the ellipse 101, and 113 is a lens.

FIG. 8 is a plan view schematically depicting an example of this type of projector type headlamp, FIG. 9 is a side view, and FIG. 10 is a front view.

1 is a concave mirror, and F is its focal point. The light source bulb 2 is provided so that the filament is located near the focal point F mentioned above.

A convex lens 3 is provided to share the optical axis Z with the concave mirror 1 described above.

8 indicates the meridional image plane of the convex lens 3, and the light emitted from the light source and reflected by the concave mirror 1 is incident on this meridional image plane.

The above incident light is modulated by the convex lens 3 and is directed forward (
8 and 9).

When a screen is provided near the meridional image plane and the light distribution pattern is shown as an isoluminance curve, it becomes as shown in FIG. 11. H-H is a horizontal line on the screen, and V-V is also a vertical line.

As shown in FIGS. 8 to 10, a shade 4 having an edge along the meridional image plane is provided. For details, see Part 10.
As shown in the figure, a cut line 4a is formed so as to recede from the meridional image plane ij. FIG. 11 also shows how the light distribution pattern described above and the shade 4 overlap. As shown in FIG. 11, the upper half of the light beam passes through. Although most of the lower half is blocked, light is allowed to pass through the portion corresponding to the cut line 4a.

The shade 4 does not necessarily have to be aligned completely with the meridional image plane i-j as shown by the solid line in FIG. −
It is also possible to configure it in a flat plate shape perpendicular to 2.

As shown in FIG. 11, the light beams partially covered by the shade 4 or 14 are focused on the meridional image planes ij and intersect with each other, so that they are projected in front of the headlight. The light beam forms a pattern that is an inversion of the pattern shown in FIG. FIG. 12 is an explanatory diagram showing the general shape of a light projection pattern using isoluminance curves on a screen provided in front of the headlight.

This conventional example is configured for left-hand traffic, and in the case of right-hand traffic, the left and right sides of FIGS. 10 to 12 are configured to be opposite. In either case, a distinct bright and dark boundary line is created along the horizontal line H-H on the oncoming lane side (right side in Figure 12), and there is also a diagonal line on the own lane side (left side in Figure 12). This creates a distinct border between light and dark.

[Problem that the invention seeks to solve]

If a distinct bright/dark boundary occurs as described above and the upper half of the vehicle on the oncoming lane side is not illuminated at all, objects on the oncoming lane will be difficult to see, making the driver feel tired and dangerous.

This invention has been made in view of the above-mentioned circumstances, and aims to provide a projector-type headlight that illuminates the oncoming lane to the extent that it does not dazzle oncoming vehicles and does not make the boundary between light and darkness stand out. It is something.

[Means for solving problems]

In order to achieve the above object, the projector type headlamp of the present invention includes a light source bulb installed near the focal point of a reflector, and the light emitted from the light source bulb is reflected by the reflector to form a shade with a cut line. In a projector-type headlamp that focuses nearby and projects the reflected light forward using a convex lens, a reflective surface is formed near the intersection of the cut line of the shade and the optical axis, and the reflective surface It is characterized in that it is set to reflect a part of light diagonally downward from the optical axis direction without reflecting light along the axis.

[Effect]

The projector type headlight configured as described above reflects a portion of the diagonally downward reflected light (light reflected by the concave mirror 1) in the vicinity of the shade so as to be biased upward by the reflective surface provided on the shade. Therefore, the above-mentioned upwardly biased light illuminates the area above the horizontal line H-H. For this reason,
A weak light is also projected onto the upper half of the oncoming lane, illuminating the upper half of the oncoming lane to the extent that the oncoming vehicle is not seen through the porthole, and blurring the boundary between light and darkness.

(Example) Figures 1 to 6 show one example of a projector type headlamp of the present invention.
An example is shown.

This embodiment is an example of improving the conventional projector type headlamp shown in FIGS. 8 to 10 by applying the present invention, and is given the same drawing reference number as the conventional example. are the same or similar structural members to those in the conventional example.

FIG. 2 is a plan view, FIG. 3 is a side view, and FIG. 4 is a front view.

A cut line 14a (FIG. 4) of the shade 14 is substantially in contact with the optical axis Z. A reflecting plate 15 is provided slightly below this cant line 14a.

The above-mentioned reflecting plate 15 is provided at a position where it does not obstruct the light passing through the optical axis 2, as shown in FIG. Then, it is set so that light reflected obliquely downward from near the upper end of the concave mirror I as indicated by arrow a is received and reflected at a shallow angle of incidence. FIG. 5(a) is a detailed view of the vicinity of the reflection plate 15.

The reflected light arrow a is reflected by the reflecting plate 15 (Fig. 3).
, Dotted line arrows, do not proceed as shown in c, but proceed as shown in arrow d. While the arrow C above was almost horizontal, the arrow d
is biased upward.

The reflected light arrow C from near the upper end of the concave mirror 1 is similarly deflected upward (as indicated by the arrow f).

The upward weak light arrows d and f generated as described above provide weak illumination (10lux to 11uχ) above the horizontal line H-H, as shown by the chain line in FIG. FIG. 5(B) shows a shade 14' in a different embodiment from the above. The shade 14' of this example is constructed in the shape of a slightly thick plate, and has a reflective surface 15' on its top surface. As a further different embodiment (not shown), a cylindrical shade along the meridional image plane is constructed like the shade 4 shown in FIG. 8, and a reflecting plate 15 as shown in FIG. 2 is attached to this. However, similar effects can be obtained.

〔Effect of the invention〕

As detailed above, according to the headlight of the present invention, the upper half of the oncoming lane is illuminated without giving a porthole to oncoming vehicles, and there is no noticeable boundary between bright and dark near the horizon. This makes it easier to see objects on the oncoming lane and has excellent practical effects in reducing driver fatigue, contributing greatly to traffic safety and the development of the automobile industry.

[Brief explanation of drawings]

1 to 6 show embodiments of the projector type headlamp of the present invention, in which FIG. 1 is a schematic perspective view, FIG. 2 is a plan view, FIG. 3 is a side view, and FIG. The figure is a front view, FIG. 5 (8) is a detailed view of the vicinity of the reflector, FIG. 5 (B) is a detailed view of a shade in an embodiment different from the above, and FIG. 6 is a layout common to both of the above embodiments. This is a light pattern chart. FIG. 7 is an explanatory diagram of a known projector type headlamp. 8 to 10 show a conventional projector type headlamp, in which FIG. 8 is a plan view, FIG. 9 is a side view, and FIG. 10 is a front view. FIGS. 11 and 12 are charts showing the optical characteristics of the above conventional example. 1... Concave mirror, 2... Light source bulb, 2a... Filament, 3... Convex lens, 4... Shade, 4a
...cut line, 14.14'...shade, 1
5... Reflective plate, 15'... Reflective surface. Patent Applicant: Ichikoh Industries Co., Ltd. Agent: Patent Attorney Masami Akimoto Figure 94 and Figure 5 (A)
Figure 5 Do B Figure 6 Figure 7 Figure 9

Claims (1)

[Claims] 1. A light source bulb is installed near the focal point of the reflector, and the light emitted from the light source bulb is reflected by the reflector and focused near the shade having a cut line, and the reflected light is projected forward by a convex lens. In a projector-type headlamp, a reflective surface is formed near the intersection of the cut line of the shade and the optical axis, and the reflective surface does not reflect light along the optical axis, but rather than the light along the optical axis. A projector-type headlamp characterized by being set to reflect a portion of diagonally downward light.