JPH0648601B2 - Projector headlight - Google Patents

Description

The present invention relates to a projector-type vehicle headlight.

[Conventional technology]

The vehicle headlamp must have a light distribution pattern that brightly illuminates the front of the own lane and does not dazzle an oncoming vehicle.

A projector-type automotive headlamp has been proposed as a headlamp that has a light distribution characteristic that meets the above requirements, has a simple lens configuration, and can be downsized in its overall shape. As the latest technology relating to this projector type headlight, for example, JP-A-58-209801 is known.

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

Reference numeral 110 is an outer focus of the ellipse 102, 110 is a dimmer plate-shaped dimmer, 112 is an outer focus of the ellipse 101, and 113 is a lens.

As for the ellipse 102, the focal point 105 is the so-called first
At the focal point, the light source is located. Also, the outer focus 110
Is the so-called second focal point and is located on the meridional image plane of the lens 113.

FIG. 8 is a plan view schematically illustrating an example of this type of projector-type headlight, FIG. 9 is a side view of the same, and FIG. 10 is a front view of the same.

Reference numeral 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.

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

Ij shown in FIG. 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 incident light is dimmed by the convex lens 3 and projected forward (rightward in FIGS. 8 and 9).

A screen is provided in the vicinity of the meridional image plane, and the light distribution pattern is shown by isolux curves as shown in FIG. H-H is a horizontal line on the screen, and V-V is a vertical line.

As shown in FIGS. 8 to 10, a shade 4 having an edge along the meridional image plane is provided. For more details, the tenth
Like 4a shown in the figure, a cut line 4a is formed so as to recede from the meridional image plane i-j. FIG. 11 also shows the degree of overlap between the above-mentioned light distribution pattern and the shade 4. As shown in FIG. 11, the upper half of the light flux passes through. Most of the lower half is blocked, but light is allowed to pass through the portion corresponding to the cut line 4a.

Since the luminous fluxes partially covered as described above are condensed on the meridional image plane i-j and intersect each other, the luminous flux projected in front of the headlight has a pattern of an inverted shape of FIG. To form. FIG. 12 is an explanatory view showing a schematic shape of a projection pattern by isoilluminance 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, FIGS. In any case, the light distribution pattern is constant and cannot be changed while the vehicle is running.

[Problems to be solved by the invention]

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a projector-type headlight capable of arbitrarily switching a light distribution pattern. As a result, it is possible to switch between the general traveling light distribution pattern and the passing light distribution pattern, and it is also possible to switch between the right-side traffic distribution pattern and the left-side traffic distribution pattern.

[Means for solving problems]

In order to achieve the above-mentioned object, the projector type headlight of the present invention has a light source bulb installed near the first focal point of the reflecting mirror, and the light emitted from the light source bulb is reflected by the reflecting mirror to form a convex lens. A second focus is formed near the meridional image plane,
In a projector-type headlight that projects forward by the convex lens, intersects with a line of intersection of a vertical plane including the optical axis and the meridional image plane of the convex lens, and has a pivot axis in a plane perpendicular to the optical axis. It is characterized in that a drive / control means is provided for rotatably supporting the shade and for rotating the shade.

[Action]

In the projector-type headlamp configured as described above, the rotating shaft is rotated to rotate the shade around it, and the cut light of the shade is used to adjust the reflected light flux of the reflecting mirror, It is also possible to make the shade parallel to the optical axis and retract it from the reflected light flux so that the light flux is not blocked. Further, it is also possible to change the dimming state by attaching two shades each having a differently shaped cut line to one rotation shaft and rotating these shades.

FIG. 13 to FIG. 16 are explanatory views in principle showing the operation of the present invention. (A) of each figure shows a perspective view schematically illustrating the shade, and (B) of each figure shows a light distribution pattern.

FIG. 13 (A) shows a state in which the shade 14 fixed to the rotary shaft 13 is vertically oriented and its cut line 14a is brought close to the optical axis Z. This state is similar to FIG. 11 in the projector type headlight of the conventional example.
Therefore, as shown in FIG. 13 (B), the light distribution pattern in the state of FIG. 13 (A) is similar to that of FIG. 12 in the conventional example.

When the rotating shaft 13 is rotated 90 ° from the above state, the first
As shown in FIG. 4 (A), the shade 14 becomes horizontal (parallel to the optical axis Z) and does not block the light beam (light beam reflected by the reflecting mirror). Therefore, the light distribution pattern in this state is shown in FIG.
As in (B), the front of the road is illuminated vertically and horizontally. This light distribution pattern is suitable for traveling when there is no oncoming vehicle.

A shade 14 having a cut line 14a similar to the above and a shade 15 having a cut line 15a different from the above are fixed to the rotating shaft 13 shown in FIG. . As shown in FIG. 15 (A), when the shade 14 is placed in a vertical posture as shown in FIG. 13 (A).
The reflected light beam is adjusted by the cut line 14a in the same manner as in, and the same light distribution pattern 15 (B) as in FIG. 13 (B).
Is obtained. When the rotary shaft 13 is rotated 180 ° from this state, the state becomes as shown in FIG. 16 (A), the cut line 15a of the reflected light beam is adjusted, and the light distribution pattern shown in FIG. 16 (B) is obtained. .

Although not shown, if two shades having cut lines of different shapes are attached to the rotary shaft, the light distribution patterns for right-hand traffic and left-hand traffic can be switched and used.

〔Example〕

1 to 6 show a projector type headlamp 1 according to the present invention.
An example is shown.

This embodiment is an example improved by applying the present invention to the conventional projector type headlamp shown in FIGS. 8 to 10, and is attached with the same drawing reference numbers as those of the conventional example. Are components similar to or similar to those in the conventional example.

1 to 3 show a state corresponding to FIG. 15 (A) of the above-mentioned explanatory view.

That is, two shades 14 and 15 are attached to the rotating shaft 13.

As will be easily understood by comparing the embodiment of FIGS. 1 and 2 with FIG. 8, the rotating shaft 13 is in a plane (a virtual plane (not shown)) orthogonal to the optical axis Z. Is located in.

The virtual plane is at a position intersecting with the "line of intersection between the meridional image plane and the vertical plane including the optical axis".

On the other hand, the shade is arranged so that its upper edge is along the meridional image plane, as described with reference to FIG. Therefore, when the rotating shaft 13 is arranged at the above-mentioned position and the shade is supported by the rotating shaft, the support of the shade
The rotary drive mechanism is small, lightweight and simple, and therefore has high operational reliability. In order to expect such effects, it is not necessary to understand the above-mentioned configuration of “intersecting the intersection line and perpendicular to the optical axis” in a strict geometric sense, and a normal error in industrial production is allowed. .

Reference numerals 16 and 17 denote bearing brackets for the rotary shaft 13, and 18 denotes a drive motor (in this example, a step motor).

In this state, the shade 1 as shown in FIG.
Dimmed by 4. From this state, drive motor 1
When 8 is operated and the rotary shaft 13 is rotated 180 °, the light is controlled by the shade 15.

Also, from this state (FIGS. 1 to 3), rotate the rotary shaft 13 to 9
When it is rotated 0 °, it becomes as shown in Figs.
Neither of the shades 14 and 15 blocks the light flux. In this state, a light distribution pattern similar to or similar to the light distribution pattern previously shown in FIG. 14 (B) is obtained, which is suitable for independent traveling (the state where there is no oncoming vehicle).

〔The invention's effect〕

As described in detail above, according to the projector type headlight of the present invention, the light distribution pattern can be arbitrarily switched while the automobile is running.

[Brief description of drawings]

1 to 6 show a projector type headlamp 1 according to the present invention.
Fig. 1 shows an embodiment, Fig. 1 is a plan view showing a state in which a reflected light beam is dimmed by a shade, Fig. 2 is a side view of the same, Fig. 3 is a front view of the same, and Fig. 4 is a shaded view of the reflected light beam. FIG. 5 is a side view of the same, and FIG. 6 is a front view of the same. FIG. 7 is an explanatory view of a projector-type headlight of a known example. 8 to 10 show a conventional projector type headlight, FIG. 8 is a plan view, FIG. 9 is a side view, and FIG. 10 is a front view. 11 and 12 are tables showing the optical characteristics of the above-mentioned conventional example. 13 to 16 are explanatory views of the operation of the projector type headlamp of the present invention. 1 ... Concave mirror, 2 ... Light source bulb, 2a ... Filament, 3 ... Convex lens, 4 ... Shade, 4a ... Cut line, 13 ... Rotating axis, 14,15 ... Shade, 1
4a, 15a ... Cut line, 16, 17 ... Bearing bracket, 18 ... Drive motor.

Claims (1)

[Claims] 1. A light source bulb is installed in the vicinity of a first focal point of a reflecting mirror, and light emitted from the light source bulb is reflected by the reflecting mirror to form a second focal point near the meridional image plane of the convex lens. In a projector-type headlight that is projected forward by, a pivot axis is provided in a plane perpendicular to the optical axis that intersects the line of intersection between the vertical plane containing the optical axis and the meridional image plane of the convex lens. A projector-type headlight, which rotatably supports a shade and is provided with drive / control means for rotating the shade.