JPH0741045Y2 - Car headlamp - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle headlamp, and more particularly to a headlamp for forming a sub beam using a discharge lamp as a light source.

[0002]

2. Description of the Related Art A discharge lamp has been attracting attention as a light source for a headlamp since it has excellent color rendering properties and luminous efficiency and excellent durability. FIG. 5 is an enlarged cross-sectional view showing the discharge part of the discharge lamp. In the discharge lamp 1, a pair of electrodes 3 is provided inside a sealed glass bulb 2 in which a rare gas for starting is sealed, The structure is such that light is emitted by the arc 4 between 3 and 3. Further, FIG. 6 shows a headlamp using the discharge lamp 1 as a light source, and the discharge lamp 1 is inserted into the bulb insertion hole 5a of the reflector 5 with the discharge shaft 5b facing forward and backward. Reference numeral 6 is a lamp body,
Reference numeral 7 is a lens in which a step of diffusing and distributing the light reflected by the reflector 5 in a predetermined direction is formed.

[0003]

However, in a conventional headlamp using a discharge lamp as a light source, the arc 4 transiently fluctuates up and down when the lamp is lit (4A indicates that the arc is in the upper position, 4A indicates that the arc is in the lower position). In this case, the light distribution pattern 8 (8A, 8B) fluctuates up and down as shown in FIG. Reference numeral 9A indicates a high luminous intensity region (hereinafter referred to as a hot zone) in the light distribution pattern 8A corresponding to the arc 4A, and reference numeral 9B indicates a light distribution pattern 8 corresponding to the arc 4B.
The hot zone in B is shown. When the hot zone moves upward, glare light is generated for an oncoming vehicle, which is not preferable.

Further, in the conventional headlamp, the discharge shaft 5b
The discharge lamp is arranged so that it is parallel to the optical axis of the headlamp, and the arc that is the light source is d
(Refer to FIG. 5), the light reflected by the reflector 5 is reflected in various directions, and it is difficult to design the light distribution by the lens step, and there are many losses in the light distribution. There was a problem.

The present invention has been made in view of the above-mentioned problems of the prior art. When a discharge lamp is used as a light source, no glare light is generated, and a light distribution design of a lens step is easy for a sub-beam automobile. To provide a headlamp.

[0006]

To achieve the above object, in a vehicle headlamp according to the present invention, a discharge lamp is arranged in front of a parabolic reflector and a direct light shade is provided in front of the discharge lamp. In a vehicle headlamp in which a lens having a step for emitting and distributing the reflected light from the reflecting mirror in a predetermined direction is disposed in front of the direct light shade, the discharge axis is orthogonal to the optical axis of the headlamp. The discharge lamp is arranged in a horizontal direction, and a window for forming a hot zone by controlling the emitting direction is formed at the lens emitting portion position of the light reflected by the upper and lower regions of the reflecting mirror of the discharge lamp discharging portion. It is the one.

[0007]

The hot zone formed near the clear cut line is formed by the reflected light in the upper and lower regions of the reflecting mirror of the discharge lamp discharge portion. Even if the arc of the discharging portion fluctuates up and down, it goes from the arc to the upper and lower regions of the reflecting mirror. Since the incident angle of light hardly changes, the direction of light reflected by the upper and lower regions of the reflecting mirror of the discharge part hardly changes, and therefore the hot zone does not fluctuate up and down. Also, by arranging the discharge part of the discharge lamp in a horizontal direction orthogonal to the optical axis of the headlamp, so-called horizontal placement, the length of the light source (arc) in the front-back direction of the optical axis of the headlamp is shortened, and the arc of the lens step It is easy to control the direction of the light emitted from the lens in consideration of vertical fluctuation.

[0008]

Embodiments of the present invention will now be described with reference to the drawings. 1 and 2 show an automobile headlamp according to an embodiment of the present invention. FIG. 1 is a perspective view of an automobile headlamp for forming a sub-beam, and FIG. 2 is a vertical sectional view of the same. .

In these drawings, reference numeral 10 is a lamp body, and a parabolic reflector 11 is integrally formed inside the lamp body 10. Reflector 1
1 is divided into an upper reflecting surface 13 having a focal length F1 and a lower reflecting surface 14 having a focal length F2 (F ₁ <F ₂ ) with a stepped dividing surface 11a as a boundary. At the focus position F of the reflector 11, the discharge lamp 20 is arranged with the discharge axis 21 in the horizontal direction orthogonal to the optical axis 12 of the headlamp.
Light emitted from the arc of the discharge lamp discharge part 22 is reflected by the reflection surface 1
The light is reflected by 3, 14 and becomes a light parallel to the optical axis 12 and is guided forward. A direct light shade 26 that blocks direct light from the discharge part 22 is arranged on the front surface of the discharge lamp 20, and a lens 30 having a diffusion step 32 is arranged in front of the direct light shade 26, and a reflecting surface is provided. The lights reflected by 13 and 14 are respectively diffused in the vertical and horizontal directions by step 32 to form the light distribution pattern P shown in FIG.

Further, at the lens positions corresponding to the optical paths of the light reflected by the reflecting surface regions 13a and 14a extending in the belt shape just above and below the discharge portion 22, windows 34 having prism steps 34a and 35a are formed. 35 is formed, and the lights L ₁ and L ₂ transmitted through the windows 34 and 35 are refracted and emitted, forming hot zones indicated by reference signs V ₁ and V ₂ . That is, the window 34 is formed with a prism step 34a for refracting the transmitted light L ₁ slightly in the lower left direction of the optical axis 12 of the headlamp, and the light reflected by the reflecting surface 13a is emitted from this window 34, Illuminate the hot zone V ₁ along the H line shown in FIG. On the other hand, the window 35 is formed with a prism step 35a for refracting the transmitted light L ₂ slightly downward to the right of the optical axis 12 of the headlamp, and the light reflected by the reflecting surface 14a is emitted from this window 35. Illuminate the hot zone V ₂ along the horizontal cut line shown in FIG. Further, the reflected light on the reflecting surface of the reflector 11 excluding the reflecting surface regions 13a and 14a is diffused by the diffusing step 32 formed in the lens 30 and illuminates a predetermined zone other than the hot zones V ₁ and V ₂ , Are combined to form a light distribution pattern P.

As described above, in this embodiment, the hot zones V ₁ and V ₂ are formed by the reflected light in the reflecting surface regions 13a and 14a whose incident / reflecting angles hardly change with the variation of the arc of the discharge part 22. Therefore, even if the arc fluctuates up and down, the hot zones V ₁ and V ₂ in the light distribution pattern P do not fluctuate up and down, and therefore there is no possibility of glare light generation.

FIG. 4 is a vertical sectional view of a headlamp according to another embodiment of the present invention. The reflector 11 is a parabolic light-reflecting surface 15 having a single focal length. The reflector 11 is located in front of the focal point F of the reflector 11 and slightly above the optical axis 12 of the headlamp. The discharge lamp 20 is arranged in a horizontal direction orthogonal to the. That is, the light emitted from the discharge portion 22 which is a light source is reflected by the reflection surface region 15a directly above the discharge portion, and the reflected light is not refracted in the vertical direction by the lens 30 but goes straight to illuminate the position along the H line. In addition, the reflected light in the reflecting surface region 15b directly below the discharge part goes straight without illuminating the lens 30 in the vertical direction and illuminates the position along the horizontal cut line, so that the discharge lamp discharge part 22 of the discharge lamp 22 with respect to the reflector 11 is illuminated. The position is set. Further, windows 36 and 37 having prism steps 36a and 37a are formed at lens positions corresponding to the optical paths of the light reflected by the reflection surface regions 15a and 15b directly above and below the discharge lamp discharge part 22, respectively. There is. That is, the prism step 36a for changing the direction of the emitted light to the window 36 to the left of the optical axis 12 and the direction of the emitted light to the window 37 slightly to the right of the optical axis 12, respectively.
37a is formed, and the light emitted from the window 36 is shown in FIG.
The hot zone V ₁ shown in FIG. 3 is illuminated, and the light emitted from the window 37 illuminates the hot zone V ₂ shown in FIG. Then, the light reflected by the areas other than the reflection surface areas 15a and 15b illuminates the zones other than the hot zones V ₁ and V ₂ by the diffusion step 32, and all the illumination zones are combined to form a light distribution pattern P (see FIG. 3). ) Is formed.

Others are the same as those in the first embodiment,
The description will be omitted by giving the same reference numerals.

[0014]

As is clear from the above description, according to the automobile headlamp of the present invention, even if the arc of the discharge lamp discharge portion fluctuates vertically in the hot zone formed near the clear cut line. Since it is formed by the reflected light in the upper and lower areas of the reflector of the discharge lamp discharge part, which hardly changes the optical path, even if the arc of the discharge part fluctuates up and down, the hot zone in the light distribution pattern does not fluctuate up and down. The generation of glare light on the oncoming vehicle is prevented. Also, because the discharge lamp is arranged so that the discharge axis is in the horizontal direction that is orthogonal to the optical axis of the headlamp, the length of the light source (arc) in the front-back direction of the optical axis of the headlamp is shortened, and the lens step is used to extend the lens. It is easy to control the direction of the emitted light, that is, to design the light distribution by steps, which facilitates the design of the lens steps.

[Brief description of drawings]

FIG. 1 is a perspective view of a vehicle headlamp that is a first embodiment of the present invention.

FIG. 2 is a vertical sectional view of the headlamp.

FIG. 3 is a diagram showing a light distribution pattern of the headlamp.

FIG. 4 is a vertical sectional view of a vehicle headlamp according to another embodiment of the present invention.

FIG. 5 is a vertical cross-sectional view of the discharge part of the discharge lamp.

FIG. 6 is a vertical sectional view of a conventional headlamp using a discharge lamp as a light source.

FIG. 7 is a diagram showing a light distribution pattern of a conventional headlamp.

[Explanation of symbols]

10 Lamp body 11 Reflector 12 Optical axis of headlamp 13a, 15a Discharge lamp Reflective surface area directly above discharge part 14a, 15b Discharge lamp Reflective surface area directly below discharge part 20 Discharge lamp 21 Discharge axis 22 Discharge part 26 Direct light Shade 30 Lens 32 Diffusion step 34, 35, 36, 37 Window 34a, 35a, 36a, 37a Prism step V ₁ , V ₂ Hot zone P Light distribution pattern

Claims (1)

[Scope of utility model registration request] 1. A discharge lamp is arranged in front of a parabolic reflector, a direct light shade is arranged in front of the discharge lamp, and light reflected by a reflector is emitted in a predetermined direction in front of the direct light shade. In an automotive headlamp having a lens with steps formed therein, the discharge lamp is arranged with its discharge axis oriented in a horizontal direction orthogonal to the optical axis of the headlamp, and the upper and lower regions of a reflecting mirror of the discharge lamp discharge part. A headlamp for an automobile, characterized in that a window for controlling a light emission direction to form a hot zone is formed at a lens light emission position of light reflected by the headlight.