JP2529087Y2 - Projector type headlight - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention relates to a light source bulb provided near a first focal point of a concave mirror, and dimming a light beam emitted from the light source valve and reflected by the concave mirror into a substantially parallel light beam. The present invention relates to a projector type headlamp provided with a convex lens for emitting light in front of a lamp.

[0002]

2. Description of the Related Art An automotive headlamp must illuminate the front of its own lane brightly and have a light distribution pattern that does not dazzle oncoming vehicles. 2. Description of the Related Art A projector-type automotive headlamp has been proposed as a headlamp having a light distribution characteristic that does not dazzle an oncoming vehicle, has a simple lens configuration, and can be downsized. FIG. 3 is a plan view schematically depicting an example of this type of projector headlight, FIG. 4 is a side view thereof, and FIG. 5 is a front view thereof.

[0003] 1 is a concave mirror and F is its first focal point. So that the filament is located near the first focal point F,
A light source bulb 2 is provided. The concave mirror 1 and the optical axis Z
And the convex lens 3 is provided. Ij depicted in FIG. 3 indicates the meridional image plane of the convex lens 3.
Light emitted from the light source and reflected by the concave mirror 1 enters this meridional image plane.

The incident light is modulated by the convex lens 3 and projected forward (to the right in FIGS. 3 and 4).

A screen is provided near the meridional image plane, and the light distribution pattern is shown by an equal illuminance curve as shown in FIG. HH is a horizontal line on the screen, and VV is a vertical line. As shown in FIGS. 3 to 5, a shade 4 having an edge along the meridional image plane is provided. More specifically, as shown in FIG. 5A, a cut line 4a is formed so as to recede downward from the horizontal section ij of the meridional image plane. FIG. 6 shows how the light distribution pattern and the shade 4 overlap. As shown in FIG. 6, the upper half of the light beam passes. Most of the lower half is blocked, but light corresponding to the cut line 4a is allowed to pass. The luminous flux partially covered as above,
Since the light is converged on the meridional image planes ij and intersects with each other, the luminous flux projected in front of the headlight forms a pattern having a shape inverted from FIG. FIG. 7 is an explanatory diagram showing a schematic shape of a light projection pattern by an equal illuminance curve on a screen provided in front of a headlight.

The light distribution pattern shown in FIG. 7 is suitable as a passing beam. However, in the traveling beam without the oncoming vehicle, the cut line 4a '
There is no need to cut off the light. Therefore, if the shade 4 is omitted from the projector-type headlamp shown in FIGS. 3 to 5 described above, the luminous flux in the hatched portions in FIG. 6 will not be cut, and the light distribution shown in FIG. A pattern is obtained. In order to switch and use the light distribution pattern of FIG. 7 and the light distribution pattern of FIG. 8 with one headlamp, the shade 4 may have a movable structure and may be advanced or retracted in the optical path. A projector-type headlamp having a movable shade based on such a concept has also been proposed (for example, Japanese Utility Model Laid-Open No. 63-165703).

[0007]

In the projector type headlamp constructed as described above, the function of the convex lens 3 is to converge the light reflected by the concave mirror 1, as can be easily understood from FIGS. In such a manner that the light is adjusted so as to be substantially parallel to the optical axis Z. Therefore, it is a short-focus lens and a thick lens. The thick convex lens 3 is a heavy member since it is generally made of a glass material. If this can be constituted by a synthetic resin material, it is effective for weight reduction and cost reduction can be expected. However, there is a problem with heat resistance as described below.

One of the great advantages of this projector type headlamp is that it can be made compact and large in luminous intensity. Therefore, the thermal load is high, and the equilibrium temperature in the use state is high. In particular, as can be easily understood from FIG. 3, the light beam emitted from the light source bulb 2 and reflected by the concave mirror 1 is concentrated on the convex lens 3. Therefore, the convex lens 3 becomes hot during use.
Therefore, when the convex lens 3 is made of a synthetic resin, the convex lens 3 suffers thermal damage such as softening, deformation and deterioration.

The present invention has been made in view of the above-mentioned circumstances, and it is possible to reduce the weight and cost by constructing a convex lens with a synthetic resin material, and furthermore, there is no possibility of suffering thermal damage, and the assembling operation can be performed. It is an object of the present invention to provide a projector-type headlamp having good characteristics.

[0010]

According to the present invention, there is provided a projector-type headlamp for achieving the above object.
A projector comprising: a light source bulb provided in the vicinity of a first focal point of a concave mirror; and a convex lens for dimming a light flux emitted from the light source bulb and reflected by the concave mirror into a substantially parallel light flux and emitting the light forward of the lamp. In the type headlamp, a filter that allows transmission of visible light and does not allow transmission of heat rays is attached to the frame, and a member that supports the convex lens is provided with a groove that fits with the frame, Further, a spring member is provided, which extends from the frame and slides on the inner wall surface of the groove.

As the above-mentioned "filter that permits transmission of visible light but does not permit transmission of heat rays", a known heat ray reflection filter or a known heat ray absorption filter can be applied.

[0012]

Since the filter in the above construction permits transmission of visible light, there is no possibility that the optical characteristics of the projector type headlamp will be adversely affected. Since the filter does not transmit heat rays, the heat rays do not reach the convex lens. Therefore, even if the convex lens is made of a synthetic resin, no problem occurs due to insufficient heat resistance.

Further, the filter is provided with a frame, and the frame is fitted in the groove of the convex lens supporting member, so that the workability of the assembly is good and the filter can be assembled with one touch. In addition, since the spring member projecting from the frame slides on the inner wall of the groove, a play preventing effect and a retaining effect are obtained, and the filter is securely held.

[0014]

FIG. 2 is a side view showing an embodiment of the projector type headlamp according to the present invention. The light source bulb 12 is arranged near the first focal point of the concave mirror 11. 19 is a socket for the light source bulb. Reference numeral 13 denotes a synthetic resin convex lens. A shade 14 is placed at the meridional image plane and near the second focal point of the concave mirror 11. Reference numeral 15 denotes a lamp frame which forms a frame of the projector type headlamp. The above-described concave mirror 11, convex lens 13, and shade 14 are fixed to the lamp frame.

The lamp frame 15 has a pair of grooves 15.
a is provided to support a filter 16 described later with reference to FIG. The filters fitted and supported in these grooves 15a are positioned at right angles to the optical axis Z as shown by the imaginary lines, and are configured to intersect the optical path from the concave mirror 11 to the convex lens 13. FIG. 1A shows the filter 16.
Is a plan view, and a bb cross section thereof is shown in FIG. The filter 16 of this example is formed of a rectangular glass plate provided with a heat ray reflective film. When implementing the present invention, it may be constituted by a transparent glass plate having a heat ray absorbing function. In short, the filter 16 is made of a material that transmits visible light and does not transmit heat rays.

A filter frame 17 made of sheet metal is mounted on each of two parallel sides of the rectangular filter 16 described above.
Tongue pieces 17a to 17e described below are cut and raised in these filter frames 17. The filter frame 17 is press-formed in a U-shape in cross section so as to sandwich the edge of the filter 16, and a leaf spring-like tongue piece 17a, 1 is formed on the surface forming the central side of the U-shape.
7b is cut and raised. In addition, two parallel sides forming two parallel sides of a U-shape in cross section are provided with leaf spring-shaped tongue pieces 17c,
17d, 17e, 17c ', 17d', and 17e 'are cut and raised.

FIG. 1C is a front view of the projector type headlamp of the embodiment shown in FIG. This FIG. 1 (C)
Since the drawing is schematically drawn to facilitate understanding of the structure, the projection is not always strictly a projection according to the JIS drafting standard.

FIG. 1C shows a pair of grooves 15a described with reference to FIG. The filter 16 with the filter frame 17 shown in FIG.
It is inserted between the pair of grooves 15a shown in FIG. Ratchet-shaped notches 15b and 15c are provided on the inner wall of the groove 15a. When the filter 16 is inserted in the direction of the arrow a, the leaf spring-like tongue piece 17 is inserted.
a and 17b slide while being pressed and bent by the inner wall surface of the groove 15a. When the filter frame 17 contacts the stopper surface 15d at the end of the groove 15a, the tongue piece 17a
Engages with the notch 15b, and the tongue piece 17b engages with the notch 15c, respectively, to fulfill the function of retaining. The above-mentioned tongue pieces 17a, 1
7b respectively presses against the inner wall surfaces of the notches 15b and 15c by an elastic restoring force, and also performs a play preventing function. A filter 16 'indicated by a broken line is a filter fitted and fixed in the groove 15a of the lamp frame 15.

As described above, when the filter 16 that does not transmit heat rays is provided so as to intersect with the optical path on the way from the concave mirror 11 to the convex lens 13, the heat rays do not reach the convex lens 13, so that the convex lens is made of synthetic resin. There is no danger of suffering thermal damage due to heat rays. In addition, the filter 16 of this embodiment can be quickly and easily mounted on the lamp frame 15 without any backlash.

FIG. 9 shows a filter according to an embodiment different from that described above. FIG. 9A is a plan view, and FIG. In the drawing, reference numeral 16 denotes a filter similar to that in the above-described embodiment, and a filter frame 18 having a U-shaped cross section is fixed to two parallel sides thereof. The filter frame 18 has curved portions 18a, 18b, 18c having spring elasticity bulging out. The filter 1 equipped with the filter frame 18 configured as described above.
6 is a lamp frame 15 similar to the embodiment shown in FIG.
Can be quickly and easily mounted in the groove 15a without play, but when the filter frame 18 of this example is used, the notches 15b and 15c shown in FIG. 1B can be omitted.

Although illustration is omitted, when implementing the present invention,
The cut and raised tongue pieces (for example, 17a, 17b) as shown in FIGS. 1A and 1B and the curved portions (for example, 18b, 18c) shown in FIG. 9 can be used in combination.

[0022]

A light source bulb provided in the vicinity of a first focal point of a concave mirror, and a convex lens for dimming a light flux emitted from the light source bulb and reflected by the concave mirror into a substantially parallel light flux and emitting the light forward of the lamp. In the projector type headlamp provided with the above, a filter that allows transmission of visible light but does not allow transmission of heat rays is mounted on the frame, and fitted to the member supporting the convex lens with the frame. If a groove is formed, and a spring member is provided that protrudes from the frame and slides on the inner wall surface of the groove, the convex lens is not heated even if the convex lens is made of synthetic resin, so that the convex lens is thermally damaged. There is no fear. By configuring the convex lens with a synthetic resin, the weight and cost of the projector-type headlight can be reduced.

Further, in the projector type headlamp according to the present invention, the filter, which is a constituent member thereof, can be mounted quickly, easily and without backlash.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a filter and its mounting operation in one embodiment of a projector type headlamp according to the present invention.

FIG. 2 is a side view for explaining a filter mounting structure in the projector type headlamp according to the embodiment.

FIG. 3 is a schematic plan view for explaining a projector type headlamp.

FIG. 4 is a side view of the same.

FIG. 5 is a front view of the same.

FIG. 6 is also a light distribution pattern chart near a shade.

FIG. 7 is a diagram of a light distribution pattern on a screen.

FIG. 8 is a light distribution pattern chart when the shade is omitted.

FIG. 9 is a two-view drawing for explaining a filter and a filter frame in an embodiment different from the above embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Concave mirror, 2 ... Light source bulb, 3 ... Convex lens, 4 ... Shade, 4a ... Cut line of shade, 4a '... Cut line of light distribution pattern, 11 ... Concave mirror, 12 ... Light source bulb, 13 ... Convex lens made of synthetic resin , 14 ... Shade, 1
5 lamp frame, 15a groove, 15b notch, 15
c: notch, 15d: stopper surface, 16, 16 ': filter, 17: filter frame, 17a to 17e, 17
a 'to 17e': tongue piece, 18: filter frame, 18
a to 18c: curved portion.

Claims (1)

(57) [Scope of request for utility model registration] 1. A light source bulb provided in the vicinity of a first focal point of a concave mirror, and a convex lens for dimming a light flux emitted from the light source bulb and reflected by the concave mirror into a substantially parallel light flux and emitting the light forward of the lamp. In the projector type headlamp provided with the above, a filter that allows transmission of visible light but does not allow transmission of heat rays is mounted on the frame, and fitted to the member supporting the convex lens with the frame. A projector-type headlamp provided with a groove that extends from the frame and a spring member that protrudes from the frame and slides on an inner wall surface of the groove.