JP2000215717A - Headlight for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a projector type headlight for vehicle, installed with a vehicle such as a automobile, allowing switching of main beam luminous intensity distribution and low beam luminous intensity distribution. SOLUTION: An opening part 2a is arranged at part of an ellipsoid of revolution-like, first reflecting mirror 2. An ellipsoid of revolution-like, second reflecting mirror, which can move between a position filling the opening part 2a and a position opening the opening part 2a, whose focus position is approximately same with the mirror 2 is arranged. A paraboloid of revolution-like, third reflecting mirror 7 making the light, passed through the opening part 2a, from a light source as approximately parallel light irradiation forward without passing through a front projection lens 4 is arranged. In low beam, the opening part 2a is filled by the second reflecting mirror, then low beam luminous intensity distribution is formed by reflected light from the first and second reflecting mirrors. In main beam, the opening part 2a is opened by the second reflecting mirror, then main beam luminous intensity distribution is formed by reflected light from the mirrors 2, 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a headlamp for a vehicle, which is installed in a vehicle such as an automobile and is capable of switching between a traveling beam distribution and a passing beam distribution depending on a traveling state. The present invention relates to a projector-type vehicle headlamp in which a single light source switches between a running beam distribution and a passing beam distribution.

[0002]

2. Description of the Related Art Conventionally, a projector-type vehicle headlamp 90 of this type is configured as shown in FIG. 12, for example, and a light source 92 is arranged at a substantially first focal point F1 of a spheroidal reflecting mirror 91. And a projection lens 93 is provided in front of the spheroidal reflecting mirror 91 such that its focal point F3 is substantially coincident with the second focal point F2 of the spheroidal reflecting mirror 91. After the reflected lights P1 and P2 of the light source 92 reflected by the mirror 91 are reflected and converged at the position of the second focal point F2, they are projected forward by the projection lens 93 installed in front to obtain a light distribution pattern as a headlight. It is configured to be.

A vertically movable shade 94 is provided in the vicinity of the focal position of the projection lens 93, and the shade 94 is moved up and down to switch between a traveling beam distribution and a passing beam distribution. Is performed. That is, when the shade 94 is located at an upper position near the focal position of the projection lens 93 shown by the solid line in FIG. 12, the reflected light P1 distributed upward through the projection lens 93 is cut by the shade 94, and A light distribution pattern for passing is formed according to the cut line formed at the upper end of the 94, and when the shade 94 is at a lower position shown by a virtual line in FIG. 12, the reflected light P1 and P2 are both blocked by the shade. In this case, the light is radiated forward and a light distribution pattern for traveling without a cut line is formed.

[0004]

However, in the case of such a conventional projector-type vehicle headlamp 90, the reflected light P1 which simply moves upward due to the movement of the shade 94.
It switches between the light distribution pattern for traveling and the light distribution pattern for passing depending on whether or not the light is shielded. However, sufficient brightness for a distant place is not obtained, and the brightness on the near side during the traveling beam is the same as that for the passing beam, so that the distance visibility is poor. And the solution of this point is an issue.

[0005]

According to the present invention, as a specific means for solving the above-mentioned conventional problems, a spheroidal first reflecting mirror and a first reflecting mirror near a first focal position of the first reflecting mirror are provided. An installed light source and a projection lens installed in front of the first reflecting mirror and having a focal point near a second focal position of the first reflecting mirror,
A vehicular headlamp provided with a shade near a focal position of the projection lens to block a part of an irradiation pattern to form a cut line, wherein an opening is provided in a part of the first reflecting mirror; A second reflector having a spheroidal shape that is movable between a position for closing the portion and a position for opening and that has substantially the same focal position as the first reflector; and the opening outside the first reflector. A third reflecting mirror in the form of a paraboloid of revolution that irradiates light from the light source that has passed through the projection lens as substantially parallel light without passing through the projection lens. A low-beam light distribution is formed by the reflected light of the first reflecting mirror and the second reflecting mirror, and at the time of the traveling beam, the second reflecting mirror opens the opening to form the first reflecting mirror. The traveling beam distribution is formed by the reflected light from the third reflector. It solves the problem by providing a vehicle headlamp, characterized in that it is.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail based on an embodiment shown in the drawings.

1 and 2 show a first embodiment of a projector type vehicle headlamp according to the present invention. FIG. 1 is a perspective view of this embodiment, and FIG. It is sectional drawing.

In the vehicle headlamp 1, one light source 3 such as a halogen bulb or a metal halide lamp is installed at a substantially first focal position of a spheroidal first reflecting mirror 2.
A projection lens 4 having a focal point near the second focal position of the first reflecting mirror 2 is provided in front of the lens. A shade 5a is formed near the focal position of the projection lens 4 to form a cut line by blocking a part of the irradiation pattern. The shade 5a is the same as that of the conventional example.

Here, in the present invention, an opening 2a is provided in a part of the first reflecting mirror 2, and the light from the light source 3
Out of the device. The first reflecting mirror 2 has a second reflecting mirror 5c for closing the opening 2a and blocking light emitted to the outside of the first reflecting mirror 2 so as to be movable between a position for closing the opening and a position for opening. It is provided in.

The second reflecting mirror 5c has a spheroidal reflecting surface having substantially the same focal position as that of the first reflecting mirror 2, and is turned by a turning shaft 6 provided on the first reflecting mirror 2. By doing so, it is configured to move between a position for closing the opening 2a and a position for opening.

Further, on the outside of the first reflecting mirror 2, as shown in a horizontal sectional view of FIG. 2 and a front view of FIG. 3, a rotating paraboloid surrounding the first reflecting mirror 2 and having the light source 3 as a substantially focal position. A third reflecting mirror 7 is provided. The whole of these is housed in the housing 8 and the outer lens 9 and
Is configured.

Here, the second reflecting mirror 5c in this embodiment is used.
As shown in FIG. 5, the light shielding member 5 is integrally formed by a shade 5a and a connecting portion 5b as a light shielding member 5, and has a structure that rotates around a rotation shaft 6. At this time, the rotating shaft 6 is, for example, an axis horizontally passed through the first reflecting mirror 2, or cylindrical ribs provided on both left and right sides of the first reflecting mirror 2 are passed through holes of the light shielding member 5. The light-shielding member 5 is rotated by a power source 11 such as an electromagnetic solenoid while a force for maintaining the rotation position is applied by a spring 10 fixed in the lamp. Power to be applied. The rotating shaft 6 is not limited to the first reflecting mirror 2 and may be provided on the third reflecting mirror 7, the housing 8, or the like.

FIG. 5 is an explanatory view showing such a turning operation of the light-shielding member 5. In a state where no tensile force is applied by the electromagnetic solenoid 11, the light-shielding member 5 is held at a position indicated by a solid line by a spring 10, and The two reflecting mirrors 5c cover the opening 2a of the first reflecting mirror, and the shade 5a is fixed near the focal position of the projection lens 4. Then, when a tensile force is applied by the electromagnetic solenoid 11, the light shielding member 5 rotates about the rotation shaft 6 as shown by the imaginary line, and the second reflecting mirror 5c closes the opening 2a of the first reflecting mirror 2. With the opening, the shade 5a retreats from near the focal position of the projection lens 4.

FIG. 6A is a vertical sectional view showing a state in which a low beam distribution is applied to the vehicular headlamp 1 configured as described above, and the second reflecting mirror 5c is the same as the first reflecting mirror 2. The shade 5a covers the opening 2a and the projection lens 4
Is fixed in the vicinity of the focal position. Therefore, the light emitted from the light source 3 does not reach the third reflecting mirror 7 and the first reflecting mirror 2
The light reflected by the second reflecting mirror 5c blocks the upward light by the shade 5a to form a cut line, and a low-beam light distribution is formed.

FIG. 7 shows the light distribution pattern at this time.
(A) is the entire light distribution pattern, (b) is the light distribution pattern by the reflected light of the first reflecting surface 2, (c) is the light distribution pattern by the reflected light of the third reflecting surface 7, (d) Indicates light distribution patterns formed by light reflected from the second reflection surface 5c.

That is, the upward light reflected by the first reflecting surface 2 is blocked by the shade 5a to form a light distribution pattern (b) having a cut line. Light (d) is added to form a light distribution pattern (a) for passing as a whole. Since the opening 2a of the first reflecting mirror 2 is closed by the second reflecting mirror 5c, the light emitted from the light source 3 does not reach the third reflecting mirror 7, but is reflected by the third reflecting mirror 7. Light (c) is not emitted.

FIG. 6B is a vertical sectional view showing a state in which a traveling beam distribution is applied to the vehicular headlamp 1. The second reflecting mirror 5 c is a position where the opening 2 a of the first reflecting mirror 2 is opened. And the shade 5a retreats from the vicinity of the focal position of the projection lens 4. Therefore, the light emitted from the light source 3 passes through the opening 2a and reaches the third reflecting mirror 7, and in addition to the light distribution pattern (b) of the first reflecting mirror 2 having no cut line as shown in FIG. The traveling beam light distribution (a) is formed by the light (c) reflected by the third reflecting mirror 7 having a substantially paraboloid of revolution having the light source 3 as a substantially focal position. At this time, since the second reflecting mirror 5c overlaps the first reflecting mirror 2, the reflected light (d) from the second reflecting mirror 5c is not emitted.

With the above-described structure, the headlamp 1 for a vehicle according to the present invention allows the opening 2a of the first reflecting mirror 2 to rotate so as to have the same focal position as the first reflecting mirror 2 at the time of passing beam distribution. Since the elliptical second reflecting mirror 5c is closed, the light is reflected by the spheroid of the first reflecting mirror 2 and the second reflecting mirror 5c as in the conventional example, and the second reflecting mirror 5c After being converged near the focal position, the light is projected forward by the projection lens 4. At this time, since the shade 5a is installed near the focal point of the projection lens 4, which is the second focal position of both reflecting surfaces, upward light is blocked and the projection lens 4
From, an optimal irradiation pattern is projected as a low beam having a cut line.

When distributing the traveling beam, the second reflecting mirror 5 is used.
Since c moves to a position where the opening 2a of the first reflecting mirror 2 is opened, the light that has passed through the opening 2a reaches the third reflecting mirror 7 having a paraboloid of revolution, and is converted into substantially parallel light by the projection lens 4. Light that irradiates far away without passing through is projected forward. Further, the shade 5a also retreats from the vicinity of the focal position of the projection lens 4 in conjunction with the second reflecting mirror 5c, so that a light distribution pattern without a cut line is formed and combined with the far irradiation light from the third reflecting mirror 7 described above. Thus, an optimal irradiation pattern is projected as a traveling beam.

Further, at the time of the traveling beam, the reflected light from the second reflecting surface 5c, which illuminated the near side, disappears from the irradiation pattern, and instead the far-side irradiation light from the third reflecting mirror 7 is added. The brightness of the far side can be suppressed and the far side can be brightened, so that the far visibility can be further improved.

In the above embodiment, the second reflecting mirror 5c has been described as being configured to rotate by the rotating shaft 6, but the present invention is not limited to this. For example, the second reflecting mirror 5c may be configured to slide back and forth. In short, any configuration may be used as long as the opening 2a is opened and closed.

In the above embodiment, the shade 5a is integrally formed as the second reflecting mirror 5c and the light-shielding member 5 by the connecting portion 5b. However, the present invention is not limited to this. May be structured separately so as to interlock with each other. When the light from the third reflecting mirror 7 has a sufficient brightness, the shade 5a is fixed and the second reflecting mirror 5c is fixed. Only the structure which moves only may be sufficient.

FIG. 9 shows an example of a light distribution pattern in the case of this structure, in which the upward light reflected from the first reflecting surface 2 is blocked by the shade 5a, and is the same as when a low beam having a cut line is used. A light distribution pattern (b) is formed, and distant irradiation light from the third reflecting mirror 7 is added to the light distribution pattern (b). As a whole, a light distribution pattern (a) in which the portion A is slightly darker than the others is formed. At this time, if the light from the third reflecting mirror 7 has sufficient brightness as described above, a light distribution pattern with high distant visibility can be obtained.

In the description so far, the direction of the light source body of the light source 3 (the filament of the electric bulb or the arc of the discharge lamp) is not particularly mentioned, but the light source body of the vehicle headlamp has the same direction as the base direction. Vertical orientation (C-8 tension) facing, horizontal orientation (C-6 tension) facing in the orthogonal direction
And those commonly used.

However, the discharge lamp used as the light source 3 currently has only a vertical installation, and such a vertical installation of the light source 3 is provided from the rear side of the first reflecting mirror 2 and the third reflecting mirror 7 in front of the vehicle. The lamp is generally inserted in the illumination direction, but has a design restriction such that the third reflecting mirror 7 can be set only above the light source 3 even outside the first reflecting mirror 2. Let's consider the case of adoption.

Since the third reflecting mirror 7 has a paraboloidal reflecting surface, for example, light emitted from directly above the light source 3 forms a vertically long image as shown in FIG. Form. As described above, it is preferable to suppress the brightness of the near object to a certain extent in order to make it easy to see a distant object.

Therefore, as in the second embodiment shown in FIG. 10, a vertically disposed light source 3 such as a discharge lamp is inserted from the side of the first reflecting mirror 2 and the third reflecting mirror 7 to thereby provide the third reflecting surface 7. 11 (b), it is possible to obtain a horizontally long image as shown in FIG. 11 (b), and to further increase the brightness in the distant place while suppressing the brightness in the near place. A light distribution pattern for a traveling beam having excellent properties can be obtained.

[0028]

As described above, according to the present invention, an opening is provided in a part of the first reflecting mirror having a spheroidal shape, and the first reflecting mirror is movable between a position for closing the opening and a position for opening. And a second spheroidal reflecting mirror having substantially the same focal position as that of the first reflecting mirror is provided, and light from the light source passing through the opening is provided outside the first reflecting mirror as substantially parallel light. A third reflecting mirror in the form of a paraboloid of revolution that irradiates forward without passing through the projection lens is provided, and in the case of a passing beam, the second reflecting mirror closes the opening and the first reflecting mirror and the second reflecting mirror. The passing beam distribution is formed by the reflected light from the mirror, and at the time of the traveling beam, the second reflecting mirror opens the opening and the traveling beam distribution is performed by the reflected light from the first reflecting mirror and the third reflecting mirror. With the configuration that light is formed, the passing beam distribution and the traveling beam The direction can be switched by the movement of the second reflector.In particular, when the traveling beam is distributed, the reflected light from the second reflector, which illuminated the near side at the time of passing beam, disappears from the irradiation pattern. In addition, the far-field light from the third reflecting mirror is added to the light, which reduces the brightness in the near area and brightens the far area, further improves the visibility in the far area, and improves the performance and reliability of this type of automotive headlamp. The effect is extremely excellent in improving the performance.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment of a vehicular headlamp according to the present invention.

FIG. 2 is a horizontal sectional view of the same embodiment.

FIG. 3 is a front view illustrating a configuration of a reflection surface according to the same embodiment.

FIG. 4 is a perspective view of a light blocking member of the same embodiment.

FIG. 5 is a vertical sectional view illustrating the operation of the light shielding member of the same embodiment.

FIGS. 6A and 6B are vertical cross-sectional views of the same embodiment, in which FIG. 6A shows a state when passing beams are distributed, and FIG. 6B shows a state when traveling beams are distributed.

FIG. 7 is a diagram showing a light distribution pattern at the time of passing beams of the same embodiment.

FIG. 8 is a diagram showing a light distribution pattern at the time of a traveling beam of the same embodiment.

FIG. 9 is a diagram showing a light distribution pattern at the time of a traveling beam when a shade is fixed.

FIG. 10 is a horizontal sectional view showing a second embodiment of the vehicular headlamp according to the present invention.

FIG. 11 is a diagram showing a light distribution pattern according to the second embodiment.

FIG. 12 is a vertical sectional view showing a conventional example.

[Description of Signs] 1 Projector type headlight 2 First reflecting mirror 2a Opening 3 Light source 4 Projection lens 5 Light shielding member 5a Shade 5b Connecting portion 5c … Second reflecting mirror 6… Rotating axis 7… Third reflecting mirror 8… Housing 9… Interlens 10… Spring 11

Claims (4)

[Claims] A first reflecting mirror having a spheroidal shape, a light source provided near a first focal position of the first reflecting mirror, and a light source provided in front of the first reflecting mirror. A vehicle headlamp comprising: a projection lens having a focal point near a bifocal position; and a shade near a focal position of the projection lens to block a part of an irradiation pattern to form a cut line. A portion is provided with an opening, and a second reflecting mirror having a spheroidal shape that is movable at a position that closes the opening and an opening position and that is substantially the same as the first reflecting mirror is provided.
Further, outside the first reflecting mirror, a rotating parabolic third reflecting mirror that irradiates the light from the light source passing through the opening as substantially parallel light forward without passing through the projection lens is provided. At the time of a beam, the second reflecting mirror closes the opening to form a passing beam light distribution by the reflected light of the first reflecting mirror and the second reflecting mirror. A headlight for a vehicle, characterized in that a traveling beam light distribution is formed by light reflected by the first reflecting mirror and the third reflecting mirror by opening the opening. 2. The apparatus according to claim 1, wherein the second reflecting mirror is moved to a position to close the opening and a position to be opened by rotating by a rotating shaft set in the lamp. Headlights for vehicles. 3. The second reflecting mirror is interlocked with the shade.
At the time of the passing beam, the second reflecting mirror closes the opening, and the shade is located near the focal position of the projection lens to form a cut line of the passing beam light distribution. 3. The vehicle headlight according to claim 1, wherein a mirror opens the opening, and the shade retreats from a position near a focal position of the projection lens. 4. A headlight for a vehicle according to claim 3, wherein said second reflector and said shade are formed integrally.