JP3401341B2 - Automotive headlamp - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automobile headlamp in which a metal halide type discharge bulb, which is a light source, is arranged near the focal point of an effective reflection surface having a paraboloidal shape, and more particularly, it passes below or to the side of the discharge bulb. The present invention relates to an automotive headlamp for forming a low beam, which is provided with a shade that contributes to forming a clear cut line of a beam.

[0002]

2. Description of the Related Art FIG. 23 shows a front view of a reflector of a headlamp (Japanese Unexamined Patent Publication No. 5-217403) of this type of prior art. A discharge bulb having an arc tube 3 extending forward and backward is inserted into the bulb insertion hole 2 of the reflector 1 having a parabolic effective reflection surface, and the light emitted from the arc tube 3 is reflected by the effective reflection surface of the reflector 1. The light is guided to the front, is diffused by the light distribution control step of the front lens (not shown) located in front of the reflector 1, and is distributed to the front.

The effective reflection surface of the reflector 1 is an upper reflection surface 1a which contributes to the formation of a light distribution pattern of a passing beam having a predetermined clear cut line, and the upper reflection surface 1a.
The light reflected by almost the entire effective reflection surface (1a, 1b) of the reflector 1 is defined by a lower reflection surface 1b that has a shape slightly different from that of a and illuminates a predetermined area of the light distribution pattern of the low beam. The passing beam is formed by this. Since the upper and lower reflecting surfaces 1a and 1b are slightly different in shape from each other, boundary lines (step portions) 4 and 4 extending in the left and right direction are formed in a substantially central portion of the effective reflecting surface of the reflector 1 in the vertical direction. On the left and right sides of the tube 3,
A band-shaped shade 5 is provided that contributes to the formation of a clear cut line of the passing beam and that blocks the light traveling toward the boundary line 4 and suppresses the generation of glare light due to the reflection at the boundary line 4. .

FIG. 24 shows another conventional technique, and is a front view of a headlamp reflector having a structure in which a passing beam is formed by using only a part of a reflecting surface. A shade 6 having an arc-shaped cross section for forming a clear cut line is provided below the arc tube 3 so that substantially the lower half of the effective reflection surface of the reflector 1 is shielded from light and only the upper half of the effective reflection surface is reflected. A light distribution pattern of the passing beam is formed. The shaded areas in FIGS. 23 and 24 indicate areas that are shaded by the shades 5 and 6.

[0005]

However, in the above-described conventional headlamp, the shade 5 (6) is provided at a position apart from the arc tube 3 to some extent.
As shown in FIG. 5 (an enlarged view of the arc tube and its surroundings in FIG. 23), the hermetically sealed glass bulb 3 of the arc tube 3 is shown.
The light L ₁ emitted upward from the portion P ₁ below the inter-electrode center O of a is not blocked by the shade 5 (6) and is reflected by the reflection surface 1a as shown in FIG. There is a problem that the light goes upward (light goes above the clear cut line of the light distribution pattern), so-called harmful glare light.

That is, the arc, which is a light source generated between the electrodes of the arc tube 3, is usually curved upwardly as shown by reference numeral 8 in FIG. Immediately after the discharge bulb is turned off and then turned on again, the arc is curved downward convexly, and the downward convex arc causes light to be emitted from the lower part of the closed glass bulb to generate the glare light as described above. There was a case to do.

Further, mercury, metal iodide and the like are enclosed in the arc tube closed glass sphere 3a in a saturated state. However, as shown by reference numeral 9 in FIG. There is a case where it remains as a precipitate (white) without being processed, and even if the arc 8 is a proper upward convex type, it is reflected and scattered by this white precipitate 9, and this scattered light L ₂ is an effective reflection surface 1a. There was a case that it was reflected by and became glare light.

Therefore, by providing the shade 5 (6) close to the light source (arc tube 3), the light emitted obliquely upward from the lower part of the arc tube closed glass bulb is shielded by the shade 5 (6) and effectively reflected. It was considered to reduce the generation of glare light due to the reflection on the surface 1a. However, the closer the shade 5 (6) is to the arc tube 3, the larger the enlargement ratio of the clear cut line formed by the upper edge of the shade becomes. Another problem has been raised that the manufacturing equipment is expensive.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object thereof is to provide a clear cut line of a clear passing beam with less glare light without increasing the mounting dimension accuracy of the cut line forming shade. An object is to provide an obtained automobile headlamp.

[0010]

In order to achieve the above object, in a vehicle headlamp according to a first aspect of the present invention, a parabolic reflecting surface and electrodes facing each other in the front and rear inside the arc tube sealed glass bulb are provided. A discharge bulb arranged so that the center of the space substantially coincides with the focal point of the reflection surface, a front lens for light distribution control provided in front of the reflection surface, and provided near the arc tube, In an automobile headlamp equipped with a cut line forming shade that contributes to the formation of a clear cut line of a passing beam by shielding a part of the light directed to the reflecting surface, in an arc tube inside the cut line forming shade At an approaching position, the obliquely upward outgoing light from the lower part of the arc tube sealed glass bulb, which becomes the light reflected by the reflective surface and directed to above the clear cut line, is blocked. A second shade that is provided, wherein
The upper edge of the second shade is cut with the center between the electrodes
Below the plane passing through the upper edge of the line forming shade
They are arranged. In claim 2 ,
2. The automobile headlamp according to claim 1, wherein the reflecting surface is formed in a shape having a focus at a position slightly deviated from the center between the electrodes toward the reflecting surface side, and the cut line forming shade is formed substantially in the reflecting surface. The second shade is composed of a pair of band-shaped light-shielding members provided on the left and right sides of the arc tube. .
According to a third aspect of the present invention, in the vehicle headlamp according to the first aspect, the reflective surface is formed in a shape having a focus at a position slightly deviated from the center between the electrodes toward the reflective surface, and the cut line forming shade is formed. Is constituted by a pair of band-shaped light-shielding members provided on the left and right sides of the arc tube, and the second shade is constituted by a light-shielding member having an arc-shaped cross section that covers the lower portion of the arc tube hermetically sealed glass bulb. It is a thing. According to a fourth aspect of the present invention, in the automobile headlamp according to the first aspect, the reflecting surface has an upper reflecting surface whose focal point is a position slightly deviated from the center between the electrodes toward the reflecting surface side, and the front lens from the center between the electrodes. The cut line forming shade is defined by a lower reflecting surface whose focal point is a position slightly shifted to the side, and the light from the arc tube closed glass bulb toward the upper and lower reflecting surface boundary lines is shielded. The second shade is composed of a pair of right and left band-shaped light shielding members, and the second shade is formed by a pair of light shielding members provided on the left and right sides of the arc tube. In claim 5 , claim 1
In the automobile headlamp described in the above, the arc tube of the discharge bulb has a structure in which it is surrounded by a glass ultraviolet shielding globe, and the second shade is applied to the ultraviolet shielding globe in a band-shaped light shielding coating portion. It is configured by. According to a sixth aspect of the present invention, in the vehicle headlamp according to the first aspect, the headlamp includes a direct shade that shields light emitted from the arc tube and heading toward a region other than the reflection surface.
At least one of the cut line forming shade and the second shade is integrated with the direct-lighting shade.

[0011]

The light emitted obliquely upward from the lower part of the arc tube hermetically sealed glass bulb connected to the glare light is blocked by the second shade provided at a position close to the arc tube. The cut line forming shade that contributes to the formation of the clear cut line of the low beam is located near the arc tube, but at a certain distance (similar to the conventional shade position) from the arc tube. Shade mounting dimensional accuracy is not required more than ever. Further, since the cut line forming shade and the second shade are both provided in the vicinity of the arc tube, the shade can be of a compact size. Further , the upper edge portion of the second shade is located below the plane formed by the center between the electrodes and the upper edge portion of the cut line forming shade, and the second shade clears the passing beam by the cut line forming shade. It does not prevent the formation of cut lines.
In the second aspect, since the substantially lower half of the reflecting surface is shielded by the cut line forming shade, the passing beam is formed only by the substantially upper half of the reflecting surface. The obliquely upward light emitted from the lower part of the closed glass bulb, which is connected to the glare light, is shielded by a pair of left and right light shielding members (second shades) provided close to the left and right sides of the arc tube. In the third aspect, since the substantially lower half of the reflecting surface is shielded by the light shielding member (second shade) having an arc-shaped cross section which is provided close to the lower side of the arc tube, only the upper half of the reflecting surface passes each other. A beam is formed,
A pair of strip-shaped light shielding members (cut line forming shades) provided on the left and right of the arc tube form a clear cut line of the passing beam. In addition, the light emitted obliquely upward from the bottom of the closed glass bulb that is connected to glare light is
It is shielded from light by a second shade that covers the lower part of the arc tube sealed glass bulb. In the fourth aspect, the passing beam is formed by both the upper reflecting surface and the lower reflecting surface, and the pair of left and right band-shaped light shielding members (cut line forming shades) form a clear cut line of the passing beam. Further, the obliquely upward light emitted from the lower part of the closed glass bulb that is connected to the glare light is shielded by a pair of left and right light shielding members (second shades) provided close to the left and right sides of the arc tube. According to claim 5, the second shade because it is constituted by a light-shielding coating portion provided on the ultraviolet shielding globe is the discharge valve components, if inserting the discharge valve bulb insertion hole, the second shade Is naturally positioned with respect to the center between the electrodes. According to the sixth aspect , the cut line forming shade and the second shade are integrated with the direct irradiation shade, the number of parts is reduced, and the cut line forming shade and the second shade can be formed only by attaching the direct irradiation shade. Installation can be omitted.

[0012]

Embodiments of the present invention will now be described with reference to the drawings. 1 to 6 show a vehicle headlamp that is a first embodiment of the present invention. FIG. 1 is a front view of the same headlamp, and FIG. 2 is a longitudinal sectional view of the same headlamp (shown in FIG. 1). (Cross-sectional view taken along line II-II), FIG. 3 is a perspective view of a reflector to which a shade is attached, FIG. 4 is an explanatory view for explaining the operation of the shade, and FIG. 5 is a horizontal cross-sectional view of the same reflector (line V shown in FIG. 1). FIG. 6 is a cross-sectional view taken along −V) as viewed from the back side of the reflector, and FIG. 6 is a diagram showing a light distribution pattern by the reflector of the same headlamp.

Reference numeral 10 denotes a container-shaped lamp body. A front lens 12 is assembled to a front opening of the lamp body 10 to form a lamp chamber S, and a discharge bulb 20 as a light source is inserted into the lamp chamber S. The attached reflector 14 is accommodated, and the reflector 14 has a structure that can be tilted vertically and horizontally by an aiming mechanism (not shown). Reference numeral 20a
Indicates a valve insertion hole provided on the rear top of the reflector 14.

In the discharge bulb 20, as shown in FIG. 5, an arc tube 22 is projected forward from an insulating base 21 and electrodes 24, 24 (see FIG. 2) are arranged inside a sealed glass bulb 23 of the arc tube. Noble gas for starting, mercury,
It has a structure in which metal iodide or the like is sealed, and emits light by arc discharge between the electrodes 24, 24. Ultraviolet ray shielding gloves 25 that surround the arc tube 22 are welded and integrated at both front and rear ends of the arc tube 22, so that ultraviolet rays in a wavelength range harmful to the human body out of the light emitted from the closed glass bulb 23 are absorbed by the globe 25. It is designed to be removed by passing through. The arc tube 22 in which the globe 25 is integrated is integrated with the base 21 by having its rear end inserted and supported by the base 21 and its front end supported by the lead support 26 extending from the base 21. It has a structure. The arc tube closed glass bulb 23 is located at a substantially focal point of the effective reflection surface of the reflector 14, and the light emission of the arc tube 23 is reflected by the effective reflection surface 15 of the reflector 14 to be adjusted to be substantially parallel light. A diffusion step 12a formed on the back surface of the lens 12 diffuses light in a predetermined left-right direction and distributes the light forward.

The reflector 14 has a rear wall on which a parabolic effective reflection surface 15 is formed, which reflects the light from the bulb 20 (arc tube 22) forward and contributes to the formation of the light distribution pattern of the headlamp. , Cylindrical direct shade 2
The light from the bulb 20 (arc tube 22) is not guided by being shielded by 7, and therefore the ineffective reflection surfaces 16a, 1 that do not contribute to the formation of the light distribution pattern of the headlamp.
6b is formed of an upper surface wall and a lower surface wall. The direct shade 27 is formed by cylindrically shaping the surface of the iron plate plated with aluminum by baking the blackened plate, and the leg 27a of the shade is used.
Is fixed to the bottom wall of the reflector 14.

As shown in FIG. 5, the effective reflection surface 15 is formed in a shape having a focal point Fa at a position slightly deviated to the rear (reflector 14 side) in the optical axis direction from the center O between the electrodes, which is the center of the light source. As shown in FIG. 2, the direction of the light L ₃ reflected by the upper reflection surface 15 is controlled so as to be slightly downward from the optical axis L of the lamp, and the predetermined passing angle indicated by P in FIG. It contributes to the formation of the light distribution pattern of the beam.

Reference numeral 31 (31L, 31R) is a pair of left and right first shades (shades for forming cut lines) that contribute to the formation of clear cut lines CL of the light distribution pattern P of the low beam, and are plated with aluminum. The iron plate is baked and then formed into an L-shape. The iron plate is fixed to the peripheral edge of the valve insertion hole 20a by a screw 28 and extends parallel to the arc tube 22.

The first right side of the reflector 14 when viewed from the front.
The upper edge of the shade 31R is located at a position horizontal to the center O between the electrodes, and a part of the light emitted from the arc tube hermetically sealed glass bulb 23 and directed to the reflecting surface 15 is part of the shade 31R.
Clear horizontal clear cut line C
L ₁ is formed on the opposite lane side. On the other hand, reflector 1
4 is viewed from the front, the upper edge of the first shade 31L on the left side is at a position inclined by 15 degrees downward with respect to the inter-electrode center O, and the light emitted from the closed glass bulb 23 and directed to the reflecting surface 15 A part of the shade 31L is shielded from light by the shade 31L, so that a clear oblique 15-degree clear cut line CL ₂ is formed on the traveling lane side.

The first shade 31 (31L, 31
As shown in FIG. 4, the upper and lower widths d ₁ and d ₂ of R) are emitted from the upper end portion P ₄ of the arc tube hermetically sealed glass bulb 23, and go beyond the upper edge of the second shade 32, which will be described later, to form the reflecting surface 15
It is formed in a predetermined size capable of surely blocking the light L ₄ directed to the. Reference numeral 32 is the arc tube 2
The second shade, which is provided at a position close to 2 and blocks the light traveling toward the lower half of the reflecting surface 15 and blocks the light traveling obliquely upward from the lower part of the arc tube, uses the ultraviolet shielding globe 25 of the discharge bulb. The outer surface is made of light-shielding coating containing alumina (Al ₂ O ₃ ) or silica (SiO ₂ ).

That is, the second shade (light-shielding coating portion) 32
As shown in FIG. 4, the left and right upper edges of the closed glass bulb 2 are
3 from the upper end P _{4 of} the first shade 31 (31
L, 31R) is provided up to a predetermined position where the light L ₄ attempting to pass therethrough can be surely shielded, and the first shade 31 (31L, 31L, 31L, 31L
The light traveling between the R) and traveling toward the lower side of the reflecting surface 15 is
The light is shielded by the shade (light-shielding coating portion) 32, and thereby the light distribution pattern P of the passing beam is formed. The second shade (light-shielding coating portion) 32 shields the light L ₅ emitted obliquely upward from the lower part of the center O between the electrodes of the hermetically sealed glass bulb 23, and is located above the clear cut line CL of the passing beam. It also has a function of blocking the generation of so-called glare light. The left and right upper edge portions of the second shade (light-shielding coating portion) 32 are flat surfaces FL and FR passing through the center O between the electrodes and the upper edge portion of the first shade 31 (31L, 31R) for forming the cut line. In the lower position, the second shade 32 has the first shade 31 (3
1L, 31R) does not prevent the formation of the clear cut line CL.

In this way, the first shade 31 (31L,
31R) is located in the vicinity of the arc tube 22, but is provided at a position relatively distant from the optical axis L.
The mounting dimension accuracy such as the mounting position of the conventional shade (Fig. 2
It is not required more than that required in (3, 24).

The second shade 32 is different from the first shade 31 (31L, 31R) in the position close to the arc tube 22 which is the light source (the outer surface of the globe 25).
As a result of this, a high mounting dimensional accuracy is naturally required. However, although the shade 32 has a function of blocking the lights L ₄ and L ₅ emitted from the closed glass sphere,
Since there is no action of forming a cut line like the first shade 31, the upper edge position of the second shade is a plane FL passing through the inter-electrode center O and the first shade 31 (31L, 31R). , FR, the position accuracy (mounting accuracy) is not important as long as the position is lower than FR and in the vicinity of these planes. Therefore, the second shade 32 is easily formed by setting the second shade forming region so that the upper edge is located slightly lower than this plane. That is, the light-shielding coating portion that is the second shade 32 does not require the mounting dimension accuracy as in the case of the first shade 31, so that the manufacturing and assembling of the first and second shades 31 and 32 are easy.

FIG. 7 is a front view of a vehicle headlamp according to a second embodiment of the present invention. In the second embodiment, the first shade 31 for forming the cut line is formed in an arc shape having a transverse cross section that covers substantially the entire lower portion of the arc tube 22, and is directed obliquely upward from the lower portion of the closed glass bulb connected to glare light. The difference is that the second shade 32 that shields the emitted light is composed of strip-shaped light-shielding coating portions 32L and 32R provided on the left and right side surfaces of the ultraviolet-shielding globe 25. Others are the same as the first embodiment. Therefore, the description thereof will be omitted by giving the same reference numerals.

8 to 13 show a vehicle headlamp according to a third embodiment of the present invention. FIG. 8 is a front view of the same headlamp, and FIG. 9 is a longitudinal sectional view of the same headlamp (FIG. 8 is a sectional view taken along line IX-IX in FIG. 8), FIG. 10 is a perspective view of a reflector to which a shade is attached, FIG. 11 is an explanatory view for explaining the action of the shade, and FIG. 12 is a horizontal sectional view of the same reflector (see FIG. 8). A sectional view taken along line XII-XII shown in FIG. 13 as viewed from the back side of the reflector, and FIG. 13 is a diagram showing a light distribution pattern by the reflector of the same headlamp.

As shown in FIG. 12, the effective reflection surface 15 of the reflector 14 has a focal point Fa at a position slightly deviated to the rear (reflector 14 side) in the optical axis direction from the center O between the electrodes which is the center of the light source. The upper effective reflection surface 15a having a common optical axis La with the optical axis L, and a position slightly deviated from the inter-electrode center O forward in the optical axis direction (on the front lens 12 side) is set as a focal point Fb, and is forward of the optical axis L. It is defined by a lower effective reflection surface 15b having an optical axis Lb inclined by 9 ° on the left side.

As shown in FIG. 9, the direction of the light L ₆ reflected by the upper reflection surface 15a is controlled so as to be slightly downward from the optical axis L of the lamp, and the reference numeral Pa in FIG.
Contributes to the formation of the predetermined light distribution pattern of the low beam. Further, the light L ₇ reflected by the lower reflection surface 15b is also slightly downward from the optical axis L, and is controlled so as to be tilted to the left by 9 ° with respect to the optical axis L as seen from the driver.
This contributes to the formation of the light distribution pattern indicated by the reference symbol Pb, and the light distribution pattern of the passing beam is enlarged toward the road shoulder of the traveling lane to enhance the visibility of the road shoulder of the traveling lane. Although the optical axis Lb is described as tilting in the left-right direction at 9 °, it has been confirmed that this tilt may be 3 to 9 °.

Further, since the upper and lower reflecting surfaces 15a and 15b have different shapes, the reflecting surface 15 has a boundary line between the reflecting surfaces (step portion) which extends from the valve insertion hole 20a while being inclined in the left-right direction.
17 and 18 are formed. Then, at the left and right lateral positions of the bulb 20, by blocking a part of the light emitted from the arc tube hermetically sealed glass sphere 23, a passing beam having a clear clear cut line is formed, and a boundary line connecting to the glare light is formed. Shades 31 (31L, 31R) and 32 (32L, for shielding light directed to 17, 18)
32R) is provided.

The first outer shade 31 (31L, 31)
R) contributes to the formation of the clear cut line CL (CL ₁ , CL ₂ ) of the light distribution pattern Pa of the low beam, and is emitted from the upper part of the center O between the electrodes of the sealed glass ball 23 as shown in FIG. Then, the light L ₈ traveling toward the upper and lower boundary surfaces (step portions) 17 and 18 between the reflecting surfaces is shielded, and the generation of glare light due to the reflection at the boundary surfaces 17 and 18 between the reflecting surfaces is prevented.

On the other hand, the inner second shade 32 (32
L, 32R) are outside the right and left of the ultraviolet shielding globe 25.
Alumina (Al₂O₃) Or silica (S
iO₂1) is formed by a light-shielding coating containing
As shown in FIG.
Part P below the center O of the gap_FiveEmitted diagonally upward from
Light L₉To shield the beam and clear the passing beam
Cut line CL (CL ₁, CL₂) From above
Generation of light, so-called glare light, is blocked. Again
The shade 32 (32L, 32R) of 2 is a closed glass ball
Part P below the center O between the electrodes of 23_FiveOut from above and below
L toward the boundary lines 17 and 18 between the reflecting surfaces of _TenTo shield the
Generation of glare light due to reflection at the boundary lines 17 and 18 between reflecting surfaces
It also acts to prevent life.

The upper left edge 32 ₂ of the shade 32 is
Since it is lower than the position of the right upper edge 32 ₁ , it is not possible to block all of the light emitted obliquely upward from the portion lower than the interelectrode center O, but it is emitted obliquely upward from the portion close to the interelectrode center O. After the reflected light is reflected by the effective reflection surface 15a,
There is no problem because it is harmless light (light that does not become glare light) that travels in the vicinity of the clear cut line CL ₂ .

Others are the same as those of the first embodiment described above, and the description thereof will be omitted by giving the same reference numerals.
14 to 16 show fourth to sixth embodiments other than the above-mentioned embodiment. In FIG. 14, in addition to the shade structure shown in the first embodiment, the rear end side of the arc tube 22 that may emit light connected to glare light on the outer peripheral surface near the base end of the ultraviolet shielding globe 25. A third shade 33 made of light-shielding coating for shielding the light emitted from the pinch seal portion and the light traveling toward the area around the valve insertion hole 20a that does not function as an effective reflection surface is formed on the second shade 32. It is characterized in that it is provided continuously.

Others are the same as those in the first embodiment described above, and the description thereof will be omitted by giving the same reference numerals.
In FIG. 15, the first shade integrally formed with the direct shade 27
Shade 31 (31R, 31L) is the arc tube 2
The second shade 32 having an arc-shaped cross section, which is arranged along the No. 2 and is screwed to the peripheral edge of the valve insertion hole 20a, is arranged close to the arc tube 22.

Others are the same as those in the first embodiment,
The description will be omitted by giving the same reference numerals. Figure 1
In FIG. 6, the first shade 31 having an arc-shaped cross section, which is made of a metal plate made of the same material as the direct-lighting shade 27, is used in the valve insertion hole 2
No. 0a having a circular cross-section formed integrally with a direct-ray shade 27, which is fixed along the arc tube 22 along the arc tube 22 and has a diameter slightly larger than the outer diameter of the arc tube 22. The second shade 32 is arranged close to the arc tube 22.

Others are the same as those in the first embodiment,
The description will be omitted by giving the same reference numerals. Figure 1
7 and 18 show a seventh embodiment of the present invention, and FIG.
Is a perspective view of a reflector with a shade attached, FIG.
[Fig. 3] is a horizontal sectional view of the same reflector, as viewed from the front side of the reflector.

In the seventh embodiment, the first shade 3
1 (31L, 32R) and second shade (32R, 32)
L) is integrally formed and is fixed to the peripheral edge portion of the valve insertion hole 20a by a screw 28. The shade is
For example, the first shade 31 and the second shade 32 can be manufactured by molding a synthetic resin, a metal plate, or welding, and the first shade 31 and the second shade 32 are integrally formed. Therefore, the structure of the shade is very simple, and the reflector is used. The attachment to 14 is also easy.

Since the other points are the same as those of the third embodiment, the description thereof will be omitted by giving the same reference numerals. 19 and 20 show an eighth embodiment of the present invention. FIG. 19 is a perspective view of a reflector to which a shade is attached, and FIG. 18 is a horizontal cross-sectional view of the same reflector as seen from the front side of the reflector. Is.

In the eighth embodiment, the arc tube 2
The third shade 3 for blocking the light emitted from the rear end side pinch seal portion and the light traveling toward the area around the valve insertion hole 20a.
3 is composed of a cylindrical light shielding member made of the same material as the direct-ray shade 27, and has a structure in which the first shade 31, the second shade 32 and the third shade 33 are integrated.

Others are the same as those in the third embodiment,
The description will be omitted by giving the same reference numerals. Figure 2
1 and 22 show a ninth embodiment of the present invention, and FIG.
Is a perspective view of a reflector with a shade attached, FIG.
[Fig. 3] is a horizontal sectional view of the same reflector, as viewed from the front side of the reflector.

In the ninth embodiment, the first shade 3
1 (31R, 31L) and the second shade 32 (32
(R, 32L) is integrated with the direct-light shade 27, and has a feature that the number of parts is very small.
Others are the same as those in the third embodiment, and the description thereof will be omitted by giving the same reference numerals.

In the first to ninth embodiments, the headlamp having the structure in which the reflector having the effective reflection surface is housed in the lamp body has been described, but the effective reflection surface is formed on the inner peripheral surface of the lamp body. The same can be applied to a headlamp having a structure in which is integrally formed.

[0041]

As is apparent from the above description, according to the automobile headlamp of the present invention, the cut line forming shade that contributes to the formation of the clear cut line of the low beam is located in the vicinity of the arc tube. , Because it is provided at a predetermined distance from the arc tube,
The dimensional accuracy of the shade attachment to the center between the electrodes is not required more than before, and the light emitted obliquely upward from the bottom of the arc tube sealed glass bulb that leads to glare light is
Since the light is shielded by the second shade provided close to the arc tube, a passing beam having a clear clear cut line without glare light can be obtained. Further, since both the cut line forming shade and the second glare light reducing shade are provided in the vicinity of the arc tube, the shade is lightweight and compact, and can be easily attached to the headlamp. In addition , the upper edge of the second shade is set below the plane formed by the center between the electrodes and the upper edge of the cut line forming shade, so that the second shade is cut line forming shade. A clear clear cut line is formed without hindering the formation of the clear cut line of the low beam.
In addition, the upper edge position of the second shade is set to be lower than the plane formed by the center between the electrodes and the cut line forming shade in advance by taking into consideration dimensional error in manufacturing and mounting error in assembly. By setting it, the formation of the second shade becomes easy as well as the formation of the first shade.
According to the second aspect, the passing beam is formed by the substantially upper half of the reflecting surface that is not shielded by the cut line forming shade, but a pair of left and right light shielding members provided close to the left and right sides of the arc tube ( Second shade)
Since the light emitted obliquely upward from the lower part of the closed glass bulb is blocked by, the passing beam with a clear clear cut line without glare light can be obtained. According to the third aspect of the invention, a light shielding member (second shade) having an arc-shaped cross section is provided close to the lower side of the arc tube, and a pair of band-shaped light shielding members provided on the left and right of the arc tube (shade for forming a cut line). ) Forms a passing beam by substantially the upper half of the reflection surface that is not blocked, but the second shade that covers the lower part of the arc tube sealed glass sphere blocks diagonally upward outgoing light from the lower part of the sealed glass sphere. You can get a passing beam with a clear clear cut line without light. According to the fourth aspect, since the passing beam is formed by both the upper reflecting surface and the lower reflecting surface (the entire effective reflecting surface), a bright passing beam having excellent visibility can be obtained. In addition, a pair of left and right light blocking members (second shades) provided close to the left and right sides of the arc tube block the obliquely upward outgoing light from the lower part of the closed glass bulb, so that there is no clear glare. A passing beam with a cut line is obtained. According to the fifth aspect , since the second shade is the light-shielding coating portion provided on the ultraviolet ray shielding globe that is the discharge bulb constituent member, the number of parts of the shade constituent member is small. Further, as the discharge valve is inserted into the valve insertion hole, the second
Since the shade is naturally positioned with respect to the center between the electrodes, the shade can be easily attached. According to the sixth aspect , since the cut line forming shade and the second shade are integrated with the direct-lighting shade, the number of parts of the shade constituting member is small. Further, by attaching the direct shade, the attachment of the cut line forming shade and the second shade can be omitted, and thus the shade can be easily attached.

[Brief description of drawings]

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

FIG. 2 is a vertical sectional view of the same headlamp (see line II- in FIG. 1).
(Sectional view along II)

FIG. 3 is a perspective view of a reflector with a shade attached.

FIG. 4 is an explanatory diagram for explaining the operation of the shade.

FIG. 5 is a horizontal sectional view of the reflector (line V shown in FIG. 1).
A cross-sectional view taken along the line -V) as viewed from the back side of the reflector.

FIG. 6 is a view showing a light distribution pattern by a reflector of the headlamp.

FIG. 7 is a front view of a vehicle headlamp that is a second embodiment of the present invention.

FIG. 8 is a front view of a vehicle headlamp that is a third embodiment of the present invention.

FIG. 9 is a vertical sectional view of the same headlamp (line IX- shown in FIG. 8).
(Cross-section view along IX)

FIG. 10 is a perspective view of a reflector with a shade attached.

FIG. 11 is an explanatory diagram illustrating the operation of the shade.

FIG. 12 is a horizontal sectional view of the same reflector (line shown in FIG. 8).
XII-XII sectional view), as seen from the rear side of the reflector.

FIG. 13 is a diagram showing a light distribution pattern by a reflector of the headlamp.

FIG. 14 is a horizontal sectional view of a reflector to which a shade is attached, which is an essential part of a fourth embodiment of the present invention, as viewed from the front side of the reflector.

FIG. 15 is a horizontal sectional view of a reflector to which a shade is attached, which is an essential part of a fifth embodiment of the present invention, as seen from the front side of the reflector.

FIG. 16 is a horizontal sectional view of a reflector to which a shade is attached, which is an essential part of a sixth embodiment of the present invention, as viewed from the front side of the reflector.

FIG. 17 is a perspective view of a reflector having a shade, which is a main part of a seventh embodiment of the present invention.

FIG. 18 is a horizontal sectional view of the same reflector as seen from the front side of the reflector.

FIG. 19 is a perspective view of a reflector having a shade, which is an essential part of an eighth embodiment of the present invention.

FIG. 20 is a horizontal sectional view of the same reflector as seen from the front side of the reflector.

FIG. 21 is a perspective view of a reflector having a shade, which is a main part of a ninth embodiment of the present invention.

FIG. 22 is a horizontal cross-sectional view of the same reflector as seen from the front side of the reflector.

FIG. 23 is a front view of a conventional headlamp.

FIG. 24 is a front view of another conventional headlamp.

FIG. 25 is a diagram for explaining the reason for becoming glare light.

FIG. 26 is a diagram for explaining the reason for becoming glare light.

FIG. 27 is a diagram showing the shape of an arc generated between electrodes.

[Explanation of symbols]

10 Lamp Body 12 Front Lens 14 Reflectors 15, 15a, 15b Parabolic Effective Reflective Surfaces 17, 18 Upper and Lower Reflector Boundary Line (Step) 20 Discharge Bulb 22 Arc Tube 23 Sealed Glass Ball 24 Electrode 27 Direct Shade 31 (31R, 31L) First shade 32 (32R, 32L) for forming a clear cut line of a low beam 32 Second shade 33 for reducing glare light Third shade O Electrode center Fa, Fb Focus L ₅ Arc tube Light emitted obliquely upward from the bottom of the closed glass bulb

Continuation of the front page (56) Reference JP-A-4-249801 (JP, A) JP-A-5-217403 (JP, A) JP-A-4-6701 (JP, A) JP-A-5-135604 (JP , A) Japanese Unexamined Patent Publication No. 8-148002 (JP, A) Actual Development 4-92303 (JP, U) Actual Development 4-12204 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB) Name) F21S 8/12

Claims (6)

(57) [Claims] 1. A discharge valve arranged so that the center of the parabolic reflection surface and the front and rear electrodes in the arc tube hermetically sealed glass bulb substantially coincide with the focal point of the reflection surface, and the reflection bulb. A front lens for light distribution control provided in front of the surface, and a cut provided in the vicinity of the arc tube, which shields a part of the light toward the reflecting surface and contributes to the formation of a clear cut line of the passing beam. In an automobile headlamp provided with a line forming shade, an arc tube hermetically sealed at a position close to an arc tube inside the cut line forming shade to become light that is reflected by the reflecting surface and goes upward toward a clear cut line. A second shade is provided for blocking the obliquely upward outgoing light from the lower part of the glass bulb, and the upper edge of the second shade is between the electrodes.
Pass the center and the upper edge of the cut line forming shade.
A headlamp for an automobile, which is arranged below a flat surface . 2. The reflection surface is formed in a shape having a focal point at a position slightly deviated from the center between the electrodes toward the reflection surface side, and the cut-line forming shade is arranged to guide light traveling toward a substantially lower half of the reflection surface. 2. A shaded member having an arcuate cross-section, which shields light, and the second shade is constituted by a pair of band-shaped light-shielding members provided on the left and right sides of the arc tube. Headlamps for automobiles. 3. The reflection surface is formed in a shape having a focus at a position slightly deviated from the center between the electrodes toward the reflection surface side, and the cut line forming shades are provided on the left and right sides of the arc tube. 2. The head for an automobile according to claim 1, wherein the second shade is constituted by a pair of band-shaped light shielding members, and the second shade is constituted by a light shielding member having an arc-shaped cross section that covers a lower portion of the arc tube hermetically sealed glass bulb. lamp. 4. The reflecting surface has an upper reflecting surface whose focal point is a position slightly shifted from the center between the electrodes toward the reflecting surface side and a lower reflecting surface whose focal point is a position slightly shifted from the center between the electrodes toward the front lens side. The cut line forming shade is defined by a side reflection surface, and the cut line forming shade is constituted by a pair of left and right band-shaped light blocking members capable of blocking light traveling from the arc tube closed glass sphere to the boundary line between the upper and lower reflecting surfaces. The vehicle headlamp according to claim 1, wherein the second shade is constituted by a pair of light shielding members provided on the left and right sides of the arc tube. 5. The arc tube of the discharge bulb is surrounded by an ultraviolet shielding globe made of glass, and the second shade is composed of a band-shaped light shielding coating portion provided on the ultraviolet shielding globe. The automobile headlamp according to claim 1, wherein the headlamp is an automobile headlamp. 6. The headlamp includes a direct shade that shields light emitted from an arc tube and directed to a region other than a reflection surface, and at least one of the cut line forming shade and the second shade is the shade. The vehicle headlamp according to claim 1, wherein the headlamp is integrated with a direct shade.