JPH0789449B2 - Car headlamp - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle headlamp using a discharge bulb as a light source.

[0002]

2. Description of the Related Art Recently, in the automotive lamp industry, attention has been paid to a discharge lamp which has good luminous efficiency and color rendering property and has a long life, and research using a discharge bulb as a headlight bulb for an automobile has been actively conducted. It's starting. And in order to start the discharge in the discharge bulb, a lighting circuit for applying a high voltage between the opposite electrodes of the discharge bulb is required. As shown in FIG. 7, the lamp body in which the discharge bulb 2 is inserted is attached. A lighting circuit housing case 3 accommodating a lighting circuit 4 is attached to the rear part of the lighting unit 1. The lighting circuit 4 is configured by mounting various electronic components on a printed circuit board 5 and integrating them.

[0003]

However, in the above-mentioned prior art, the printed circuit board 3 is merely fixedly held in the case 3 by screwing or bonding, and the vibration resistance of each electronic component constituting the lighting circuit 4 is improved. And there was a problem in waterproofness. Therefore, if the periphery of the printed circuit board in the case 3 is filled with resin, that is, so-called resin molding is performed, the above-mentioned problem is solved. However, another problem that the weight in the case 3 is increased by the amount corresponding to the resin in the case 3 (specific gravity of the mold resin is 1.37) and the headlamp is heavy is caused.

The present invention has been made in view of the above problems, and an object thereof is to provide a lighting circuit, which is indispensable for lighting the discharge bulb, in a lighting circuit accommodating chamber at the rear of the lamp body in an automobile headlamp using a discharge bulb as a light source. Another object of the present invention is to provide an automobile headlamp that can be housed with good water resistance and vibration resistance and does not increase the weight.

[0005]

In order to achieve the above object, in a vehicle headlamp according to the present invention, a vehicle headlamp using a discharge bulb as a light source,
A lighting circuit accommodating chamber is formed in the rear part of the lamp body, and the lighting circuit for the discharge bulb is housed therein by resin molding with resin mixed with a hollow glass body.

According to a second aspect of the present invention, the lighting circuit accommodating chamber is formed in a lighting circuit case attached to the lamp body. Further, in claim 3, the lighting circuit accommodating chamber is formed integrally with the lamp body.

[0007]

[Function] The resin filled in the lighting circuit housing without any gap secures the waterproofness and vibration resistance of the lighting circuit. Further, the hollow portion of the glass hollow body dispersed in the resin reduces the specific gravity of the resin, and reduces the weight of the entire resin molded portion in the lighting circuit housing chamber.

[0008]

Embodiments of the present invention will now be described with reference to the drawings. 1 to 4 show an embodiment of the present invention, FIG. 1 is a front view of an automobile headlamp in which a clearance lamp is integrated, and FIG. 2 is a horizontal sectional view of the headlamp.
FIG. 3 is a perspective view showing the same headlamp viewed from the rear side and showing the surroundings of the lighting circuit housing unit in an exploded manner, and FIG. 4 is an enlarged cross-sectional view of a connecting portion between the lamp body side opening and the lighting circuit housing unit. .

In these figures, reference numeral 10 is a container-shaped lamp body made of synthetic resin, and the outer surface of the lamp body 10 is made of Cu, N or the like by conductive coating or metallikon treatment.
Conductive layer 11 (11 made of a conductive material such as i-based or Zn-based material)
a) has been formed. Then, the headlamp is fixed to the vehicle body 19 by stud bolts 18a and nuts 18b provided on the rear surface of the lamp body 10 (see FIG. 2).
However, the conductive layer 11a is electrically connected to the vehicle body 19 through the stud bolt 18a made of a metal conductive material.

In the lamp chamber space formed by the lamp body 10 and the front lens 16 assembled in the front opening of the lamp body, the light projection unit 20 for forming the sub beam of the headlamp and the bulb 34 for the clearance lamp are provided.
Are provided adjacent to each other, and the light projection unit 20 is supported on the back side of the lamp body 10 and has two aiming screws 12 and 13 (see FIG. 3) extending forward and one supported by the lamp body. It is tiltably supported by an aiming mechanism including a ball joint (not shown). Code 1
Reference numeral 4 denotes a cover made of synthetic resin, which is arranged around the light projection unit 20 and engages with the lamp body 10 in a concavo-convex lance. The surface of the cover 14 has a mirror surface formed by aluminum vapor deposition. A reflector 32 of the clearance lamp 30 is integrally formed on the side of the cover 14, and a clearance lamp bulb 34 inserted into the rear wall of the lamp body 10 extends forward through the reflector 32. There is.

The light projection unit 20 includes a substantially ellipsoidal metallic reflector 22 and a discharge bulb 4 inserted into a bulb insertion hole 23 formed at the rear top of the reflector.
0, the projection lens 26 is fixed to the front surface, and the metal lens holder 2 is attached to the front opening of the reflector 22.
It has a structure in which 4 and 4 are integrated. Reference numeral 25 is a locking cap for fixing and holding the discharge bulb 40 in the bulb insertion hole 23.

The discharge bulb 40 has a structure in which a discharge lamp 44 is supported by a pair of lead supports 42a, 42b projecting from the front surface of an insulating base 41, and the discharge portion of the discharge lamp 44 has a first focus position F of the reflector 22. Located in ₁ . A cylindrical ultraviolet shielding globe 46 that surrounds the discharge lamp 44 is fixedly held on the front surface of the base 41 via a ceramic disk 48, and the light emitted from the discharge portion passes through the ultraviolet shielding globe 46. At that time, ultraviolet rays in a harmful wavelength range are cut off. In the vicinity of the second focus position F ₂ of the reflector 22,
A shade 28 for forming a clear cut, which is integrated with the lens holder 24, and an ultraviolet shielding filter 29, which is fixed and held by a metal leaf spring member 29a, are provided on the lens holder 24. The light emitted from the discharge portion of the discharge lamp 44 is reflected by the reflector 22, converges on the second focal point F ₂ of the reflector 22, and is collimated by the projection lens 26 to be projected forward.

Reference numeral 50 is a lighting circuit housing unit in which a lighting circuit 51 for a discharge bulb is housed in a case, which is attached to the rear portion of the lamp body 10. The lighting circuit accommodating unit 50 applies a high voltage to the electrodes of the discharge lamp 44 to continuously perform stable discharge.
Is housed in the lighting circuit housing chamber S of the aluminum case 52 and integrated by resin molding. The lighting circuit 51 integrated on the printed circuit board is electrically connected to the vehicle body through the ground circuit. ing. Lighting circuit 51
Is a connection cord 72 extending outside the lighting circuit housing unit 50
Is connected to a ballast circuit inside a case 70 provided below the headlamp, and is further connected to a discharge bulb 40 via a lead wire L led out to the front of the case.
Reference numeral 59 is a female connector connected to the lead wire L and is connected to a male connector 49 on the discharge bulb side.

Further, the lighting circuit 5 is filled in the case 52.
In the resin mold portion M in which 1 is integrated with the case 52, innumerable glass hollow bodies are dispersed to form the resin mold portion M.
The overall specific gravity has been reduced. That is, a glass hollow body material having a specific gravity of about 50 μm, which has a smaller specific gravity than these (a material called a “glass balloon” manufactured by Sumitomo 3M, having a specific gravity of 0.15) is added to a resin material composed of a main agent and a curing agent It is composed of a mixed material that is mixed by mixing. The weight ratio of this glass hollow body material added to the resin material is the resin material 1
However, in the present embodiment, it is 7.5. Although this is made lighter by adding 8 or more by weight ratio, the viscosity of the resin as a whole becomes too large, and the resin cannot sufficiently penetrate into the gaps between the electronic components that make up the lighting circuit, resulting in waterproofness and vibration resistance. The problem remains. On the other hand, if the weight ratio of 3 or less is added, the weight reduction is insufficient. Therefore, the glass hollow body material added to the resin material 100 is preferably in the range of 3 to 8 by weight ratio. When the glass hollow body material 5 is added to the resin material 100 in a weight ratio, the specific gravity of the entire resin mold portion is 1.14 as compared with the specific gravity of 1.37 when the glass hollow body material is not added at all.
Became. If 7.5 is added in the same weight ratio,
The inventor has confirmed that the specific gravity of the entire resin mold portion is 0.98 (in the case of this embodiment).

A synthetic resin cylindrical extension 54 is integrally fastened to the aluminum unit case 52 of the lighting circuit housing unit 50 by a screw 53, and the extension 54 is provided on the rear top of the lamp body 10. The circular opening 62 is engaged with a bayonet, and is further screwed to the lamp body 10 by a tapping screw 68. That is, a cylindrical rear protruding portion 60 is erected on the rear wall of the lamp body 10 behind the discharge bulb 40, and a circular opening portion 62 for inserting a unit is formed therein, and a peripheral edge portion of the opening portion 62 has a peripheral portion. An inner protrusion 63 and a notch 63a are formed at three positions equally divided in the direction. On the other hand, on the outer periphery of the front end portion of the extending portion 54, a collar 55 that abuts the peripheral edge portion of the opening and three outer projections 56 that engage with the inner projection 63 on the opening side in a bayonet are formed. When the lighting circuit housing unit 50 is rotated clockwise, the outer protrusion 56 and the inner protrusion 63 are aligned.
Are engaged with each other in the front-rear direction of the headlamp, and the extending portion 54 is temporarily fixed to the opening 62. A ring-shaped seal packing 58 is interposed between the outer protrusion 56 on the extension side and the inner protrusion 63 on the opening side to enhance the adhesion of the bayonet engagement portion and seal the engagement portion. Further, the unit case 52 has a rectangular shape so that it can be easily grasped by a hand, and further, a concave portion 52a is formed on the outer side surface thereof. A boss 64 having a screw hole 64a is formed in the vicinity of the protrusion 60 forming the opening 62,
On the other hand, a plate-like protrusion 57 having a screw hole 57a is formed on the flange 55 of the extending portion 54. When the unit 50 is bayonet-engaged with the opening 62, the plate-like protrusion 57 is brought into pressure contact with the projecting end of the boss 64, and the screw holes 64a and 57a are aligned with each other. Then, the tapping screw 68 is screwed into the screw hole 57a to fix the lighting circuit housing unit 50 in the circumferential direction of the circular opening 62.

Also, on the outer surface of the cylindrical extending portion 54,
The conductive layer 11 (11b) is formed similarly to the lamp body 10, and the tapping screw 68 secures the electrical continuity between the extended portion side conductive layer 11b and the lamp body side conductive layer 11a. That is, as shown in FIG. 4, the conductive layer 11 b ₁ formed on the surface of the plate-like protrusion 57 and the conductive layer ₁ formed on the tip surface of the boss 64.
1a ₁ is brought into pressure contact with the tapping screw 68 to ensure electrical conduction between the conductive layers 11a and 11b. In addition, the aluminum unit case 52, which is a good conductor, and the conductive layer 11b on the extension 54 side,
Electrical continuity is secured through a screw 53 that fastens the extension portion 54 to the lighting unit 51 of the lighting circuit 51.
It is connected to the ground terminal 51a of the inner ground circuit by a cord 51b. Therefore, the conductive layers 11a and 11b surrounding the discharge bulb 40 and the discharge bulb lighting circuit 51 are formed.
And aluminum unit case 52 which is a conductive layer
Has electrical continuity with the vehicle body via the ground terminal 51a of the lighting circuit. Therefore, the electromagnetic waves generated from the discharge bulb 40, the lighting circuit 51, the lead wire L, and the like are guided from the conductive layers 11a and 11b and the unit case 52 to the vehicle body through the earth circuit, so that they act as noise on electrical components outside the headlamp. There is no. In addition, the conductive layer 11a,
11b and the unit case 52 are the stud bolts 18
Since electrical continuity is ensured with the vehicle body even through a, even if the electrical continuity path through the grounding terminal 51a of the lighting circuit becomes non-conducting, the stud bolt 18a The noise is shielded by the electrical conduction path through.

Even if an electromagnetic wave is generated from other electric components around the headlamp, the electromagnetic wave is electrically connected to the conductive layer 11 (11).
a, 11b) and the aluminum unit case 52 that functions as a conductive layer, the lighting circuit 32 in the lamp body 10 is not affected by electromagnetic waves generated outside the headlamp.

Although the conductive layer 11a is formed on the outer surface of the synthetic resin lamp body in the above embodiment, the conductive layer may be formed on the inner surface or both the inner and outer surfaces of the lamp body. The unit case 52 was made of aluminum, which is a good conductor, but made of synthetic resin,
A conductive layer may be formed on the outer surface and / or the inner surface. Further, instead of forming a conductive layer made of a conductive material, the lamp body 10, the unit case 52, and the extension portion 54 are each formed of a conductive resin, and the lamp body and the extension portion are the same as the unit case 52 described above. ,
It may be formed of a conductive metal.

FIG. 5 is a vertical sectional view of a headlamp according to a second embodiment of the present invention. In the second embodiment, the lamp body 10A is made of a conductive resin, and the lighting circuit housing unit 50A is bayonet-engaged with the lamp body 10A. Further, the lighting circuit case 52A includes the first
The lighting circuit case 52 and the extending portion 54 shown in the embodiment are made of aluminum die-cast, and the lighting circuit 51 is integrated with the lighting circuit housing chamber S in the case by resin molding. Others are the same as those in the first embodiment, and the description thereof will be omitted by giving the same reference numerals.

FIG. 6 shows a third embodiment of the present invention. In the two embodiments described above, the lighting circuit housing units 50, 5 separate from the lamp body are provided at the rear of the lamp body.
0A is attached, but this embodiment is different in that the lighting circuit 51 is directly resin-molded in the aluminum lamp body 10B. That is, the rear bulging portion 5 is provided at the rear of the lamp body 10B.
0B is formed, a lighting circuit housing chamber S is formed inside the bulging portion 50B, and the lighting circuit 51 is integrated with the lighting circuit 51 by resin molding. Reference numeral 51b is a code for connecting the aluminum lamp body 10B and the ground terminal 51a of the lighting circuit. The other points are substantially the same as those of the first embodiment, and the description thereof will be omitted by giving the same reference numerals.

In the first to third embodiments, the present invention has been described with reference to the projection type headlamp which distributes light by the light projection unit, but the present invention controls the light distribution of the parabolic reflector and the front lens. The same applies to a reflective headlamp that distributes light in steps.

[0022]

As is clear from the above description, according to the headlamp for an automobile of the present invention, the resin mold portion filled in the lighting circuit housing enters the lighting circuit case and the lighting circuit without a gap. Therefore, the waterproofness and vibration resistance of the lighting circuit are secured. Further, the hollow part of the glass hollow body dispersed in the resin mold part reduces the specific gravity of the resin mold part and the weight of the resin mold part is reduced, so that the weight of the headlamp can be reduced.

[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 horizontal sectional view of the headlamp.

FIG. 3 is a perspective view of the headlamp as seen from the back side.

FIG. 4 is a partially enlarged sectional view of a bayonet engaging portion between the lighting circuit housing unit and the lamp body side opening.

FIG. 5 is a vertical cross-sectional view of a vehicle headlamp that is a second embodiment of the present invention.

FIG. 6 is a vertical cross-sectional view of an automobile headlamp that is a third embodiment of the present invention.

FIG. 7 is a sectional view of a conventional headlamp.

[Explanation of symbols]

10, 10A, 10B, 10C Lamp body having conductive function 11 (11a, 11b) Conductive layer 40 Discharge bulb which is a light source 50, 50A Lighting circuit housing unit 50B Lighting circuit housing bulge 51 Lighting circuit S Lighting circuit housing chamber M Resin molding part that fixes the lighting circuit

Claims (3)

[Claims] 1. A headlamp for an automobile using a discharge bulb as a light source, wherein a lighting circuit housing chamber is formed at a rear portion of a lamp body, and the lighting circuit for a discharge bulb is resin-molded with a resin containing a hollow glass body. Automotive headlamps characterized by the above. 2. The headlamp for an automobile according to claim 1, wherein the lighting circuit housing is formed in a lighting circuit case attached to a lamp body. 3. The vehicle headlamp according to claim 1, wherein the lighting circuit housing chamber is formed integrally with a lamp body.