JPH0353367Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a projector type automobile 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 Application Laid-Open No. 58-209801 is known.

FIG. 3 shows the above-mentioned known projector type headlamp. The headlight of this known example is provided with a shell-type 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 to the axially horizontal longitudinal section, the elliptical portion 10 of every axial section
The focal points 105 of 1,102 and the corresponding vertices 104 of the elliptical portions 101, 102 of all axial sections coincide.

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

FIG. 4 is a plan view schematically depicting an example of this type of projector type headlamp, FIG. 5 is a side view, and FIG. 6 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.

I-j drawn in FIG. 4 indicate the meridional image plane of the convex lens 3, which emits light from the light source and passes through the concave mirror 1.
The light reflected by the lens enters this meridional image plane.

The above-mentioned incident light is modulated by the convex lens 3 and projected forward (to the right in FIGS. 4 and 5).

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. H-H is the horizontal line on the screen,
V-V is also a vertical line.

As shown in FIGS. 4 to 6, a shade 4 having an edge along the meridional image plane is provided. Specifically, as shown in 4a shown in FIG. 6, a cut line 4a is formed so as to recede downward from the horizontal section ij of the meridional image plane. FIG. 7 shows how the light distribution pattern described above and the shade 4 overlap. As shown in FIG. 7, the upper half of the luminous 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.

As the partially covered light beams as described above are focused on the meridional image planes ij and intersect with each other, the light beams projected in front of the headlight have a pattern that is an inversion of the one shown in FIG. 7. form. FIG. 8 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. 6 to 8 are configured to be opposite.

[Problem that the invention attempts to solve]

Assuming that you are driving on a straight two-lane road while illuminating the road ahead with a headlamp that has a light distribution pattern as shown in Figure 8, this light distribution will be The pattern is immutable.

FIG. 9 schematically depicts the forward field of view when driving on a straight road, and in this case, the V-V line almost coincides with the center line of the road. Arrow j indicates the traveling direction of the host vehicle, and arrow t indicates the traveling direction of the oncoming vehicle.

When the above-mentioned arrow j and arrow t are drawn on the above-mentioned light distribution pattern (Fig. 8), it becomes as shown in Fig. 10.
The vicinity of the own vehicle traveling direction arrow j is illuminated, and the oncoming vehicle traveling direction arrow t is located in an area that is not illuminated. This allows you to see what's ahead of your vehicle without dazzling oncoming vehicles.

Next, FIG. 11 shows the forward visibility when driving on a right-hand curve. Arrow R indicates the center line, and arrow R indicates the traveling direction of the own vehicle. Similarly, the forward view of a left-turning curve is as shown in FIG. 12, where arrow L is the center line and arrow l is the direction of travel of the oncoming vehicle.

The above vehicle driving direction arrow r (right-turning curve)
When written on the light distribution pattern, it becomes as shown in Fig. 13, and the area in front of the own vehicle in the direction of travel is not illuminated.

Furthermore, if the oncoming vehicle traveling direction arrow l (left-turning curve) is drawn on the light distribution pattern, it will become as shown in FIG. 13, and the oncoming vehicle will enter into the illumination range.

For these reasons, with a fixed light distribution pattern as shown in FIG. 8, the area in front of the own vehicle in the traveling direction is not illuminated when turning right, and it dazzles oncoming vehicles when turning left.

In order to solve these problems, it may be possible to support the headlight so that it can be rotated from side to side with respect to the vehicle body, but this has the disadvantages that the device is complicated, large and heavy, and expensive.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a projector-type headlamp with a simple and inexpensive configuration that allows the illumination area to be freely adjusted in the left and right directions.

[Means for solving problems]

The projector-type headlight of the present invention created to achieve the above purpose has 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 cut line. Applied to a projector-type headlamp that focuses near the shade and projects the reflected light forward by a convex lens, the shade is arranged along the meridional image plane of the convex lens, and
Means for guiding the shade in a horizontal direction and in a direction perpendicular to the optical axis is provided, and the shade is reciprocated in a horizontal direction perpendicular to the optical axis by means of a rack gear fixed to the shade and a pinion gear attached to a motor. It has a structure that allows it to be driven.

[Effect]

As explained with reference to Figs. 7 and 8, the area above the H-H line in the illumination luminous flux distribution pattern in Fig. 8 is restricted because the shadow of the shade is projected. . Therefore, when the shade is moved from side to side, the cut line on the projected luminous flux distribution pattern moves from side to side, causing the illuminated area to expand or contract to the left.

〔Example〕

FIG. 1 shows an embodiment of a projector type headlamp according to the present invention, FIG. 1A is a plan view, and FIG. 1B is a side view.

This embodiment is based on the conventional example (Figs. 4 and 5).
This is an improvement by applying the present invention to the conventional example, and the same drawing reference numbers as in FIGS. 4 and 5 refer to the same or similar structural members as in the conventional example.

Reference numeral 5 denotes a shade constructed by applying the present invention, which is disposed along the meridional image plane of the convex lens 3, and is moved in the horizontal direction (perpendicular to the optical axis) by a shade guide 6. Figure 1A
It is supported so as to be slidable in the vertical direction in FIG.

A rack gear 7 is fixed to the shade 6, and a pinion gear 8 is meshed with the rack gear 7. 9 is a motor for driving the pinion gear.

In this example, when the motor 9 is rotated forward and reverse,
The shade 5 moves left and right in the irradiation direction (arrow Z).

FIG. 2 shows a light distribution pattern in this embodiment, and the V-V line, H-H line, and isoluminance curve are substantially the same as in the conventional example (FIG. 8).

Cut line on the light distribution pattern shown in Figure 2
Cs shows the state when the shade 5 is positioned in the center (the state shown in FIG. 1A).

When the shade 5 is moved to the right in the irradiation direction (arrow Z), the cut line in Fig. 2 is an inverted image of the cut line, so it moves to the left like Cr, resulting in a light distribution that does not dazzle oncoming vehicles on counterclockwise curves. becomes.

Furthermore, when the shade 5 is moved to the left in the irradiation direction, the cut line in FIG. 2 moves to the right as indicated by Cl, and the front of the own vehicle's path in the clockwise curve is brought into the illumination area.

[Effect of idea]

As described in detail above, the projector type automobile headlamp of the present invention has a simple, compact, lightweight, and inexpensive configuration without the need to swing the entire headlamp from side to side.
The lighting area can be freely adjusted left and right.

[Brief explanation of drawings]

FIG. 1 shows an embodiment of a projector type automobile headlamp according to the present invention, in which FIG. 1A is a plan view and FIG. 1B is a side view. FIG. 2 is an explanatory diagram of the operation and effect of the above embodiment. FIG. 3 is an explanatory diagram of a known projector type headlamp. 4 to 6 show a conventional projector type headlamp, in which FIG. 4 is a plan view, FIG. 5 is a side view, and FIG. 6 is a front view. FIGS. 7 and 8 are charts showing the optical characteristics of the above-mentioned conventional example. FIGS. 9 to 13 are explanatory diagrams of the problems of the conventional example. 1... Concave mirror, 2... Light source bulb, 3... Convex lens, 4... Shade, 4a... Cut line,
5... Shade, 6... Shade guide, 7... Rack gear, 8... Pinion gear, 9... Motor.

Claims (1)

[Claims for Utility Model Registration] A light source bulb is installed near the focal point of a reflecting mirror, and the light emitted from the light source bulb is reflected by the reflecting mirror and focused near the shade having a cut line, and then In a projector-type headlamp that projects reflected light forward, the shade is disposed along the meridional image plane of the convex lens, and means for guiding the shade in a horizontal direction and in a direction perpendicular to the optical axis is provided. A projector type automobile headlamp, characterized in that the shade is reciprocally driven in a horizontal direction perpendicular to an optical axis by a rack gear fixed to the shade and a pinion gear attached to a motor. light.