JP2003068134A - Headlamp of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a headlamp of vehicle 1 capable of restraining internal temperature rise of a lighting circuit part by exposing part of the light circuit part 8 fixed to a reflector 3 to cool it by the outside air while keeping the inside of a lamp housing 2 airtight regardless of the attitude of the reflector 3. SOLUTION: This vehicular headlamp comprises: an opening part 2b opened in the housing 2 on the side facing to the lighting control circuit 8 for exposing an end face 81a of the control circuit 8 to the outside, and a diaphragm 9 formed into a nearly annular shape with a material having flexibility, having its outer circumferential side firmly fixed to the entire circumferential edge of the opening part 2b and having its inner circumferential side firmly fixed to or pressingly brought into contact with the outer circumferential side of the end of the end face 81a. Thereby, while always keeping the airtightness inside the lamp housing 2, the end face 81a of a case 81 of the control circuit 8 fixed to the reflector 3 is cooled by the outside air to restrain the internal temperature rise of the control circuit 8, so that thermal load on circuit elements can be reduced.

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 lamp and is suitable for use in an automobile.

[0002]

2. Description of the Related Art In recent years, a discharge lamp has been used as a vehicle headlight. A discharge lamp is an arc discharge type lamp that fills a discharge lamp bulb (light emitting tube) with xenon gas, etc., and causes a discharge phenomenon between a pair of electrodes to emit light. 7 compared to other halogen lamps
It is possible to obtain twice or more the amount of light with 0% power saving. Therefore, it can be expected to improve the visibility by using the headlight for a vehicle.

In general, a discharge lamp generates a high voltage of several kV to several tens of kV at the time of starting the lighting, and by applying this voltage to the discharge lamp, the discharge is instantly started to light the lamp.
After starting, power of about 35 W is applied to maintain lighting. Therefore, in order to light the discharge lamp, a dedicated lighting control circuit is required. The lighting control circuit is mainly composed of a converter section for boosting a DC voltage from the battery, an inverter section for converting the DC voltage into an AC voltage, and an igniter section for generating a high voltage of several tens kV.

In a vehicle, the lighting control circuit is generally mounted outside the lamp housing of the headlight. In this case, a high voltage supply wire and a connector for connection are required to supply a high voltage to the discharge lamp, and the device cannot be downsized. In addition, a mounting space on the vehicle is required, and man-hours for mounting and wiring are required. Furthermore, the high-voltage supply wire requires a shield means for suppressing the influence of electrical noise generated from the wire, which increases the cost.

Therefore, it is conceivable to mount the lighting control circuit inside the lamp housing and directly connect the lighting control circuit to the discharge lamp bulb. For example, it has been devised that the lighting control circuit is fixed to the back surface of the reflector, an electric connector is built in the lighting control circuit, and the discharge lamp bulb is directly connected to this connector. With this method, the size of the vehicle headlamp can be reduced, and the high-voltage electric wire between the discharge lamp bulb and the lighting control circuit is not required, and noise radio wave radiation and power loss due to the high-voltage electric wire can be eliminated.

[0006]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention By the way, the discharge lamp bulb has a high temperature during lighting. Generally, the lamp housing is provided with a vent hole for eliminating a pressure difference between the inside and the outside of the lamp housing. However, the size of this vent is
It is set to the minimum necessary to prevent the intrusion of moisture and foreign matter, and almost no air flow passes through the lamp housing. Therefore, when the discharge lamp bulb is turned on, the temperature inside the lamp housing becomes high. That is, as the ambient temperature of the lighting control circuit rises, the lighting control circuit receives heat conduction or heat radiation directly from the discharge lamp bulb, and the temperature of the lighting control circuit becomes high. As a result, there is a concern that an excessive heat load will act on the circuit elements incorporated in the lighting control circuit. As a countermeasure against this, circuit elements and substrates having excellent heat resistance have been adopted, but there has been a problem that the cost is increased and the size is increased.

As another countermeasure, an opening is provided in the lamp housing, a part of the lighting circuit section fixed to the reflector is exposed from the opening to the outside of the lamp housing, and is cooled by the outside air to be lit. It can be considered to suppress the internal temperature rise of the circuit section. In this case, in order to maintain the airtightness inside the lamp housing, a sealing means for closing the gap between the opening and the lighting circuit is required.

In the process of assembling the vehicle headlight, the reflector is moved to adjust the optical axis.
In addition, when the vehicle posture changes due to changes in the personnel arrangement in the vehicle or the loading conditions of the luggage, the actuator moves the reflector to maintain the optical axis of the headlight in a predetermined direction. There is also a light. For this reason, the shape of the gap between the opening and the lighting circuit varies depending on the product or depending on the operating conditions, so it is difficult to always reliably seal this gap.

The present invention has been made in view of the above points, and an object thereof is to maintain the airtightness inside the lamp housing regardless of the posture of the reflector, and to provide a lighting circuit portion fixed to the reflector. (EN) It is possible to provide a vehicle headlamp that can effectively suppress an increase in the internal temperature of a lighting circuit section by exposing the section to the outside and cooling by the outside air.

[0010]

In order to achieve the above object, the present invention employs the following technical means.

The vehicle headlamp according to claim 1 of the present invention has an opening formed in the lamp housing on the side facing the lighting circuit section, and exposing the end of the lighting circuit section to the outside.
Sealing means formed of a flexible material in a substantially annular shape, the outer peripheral side of which is adhered and fixed to the entire periphery of the opening, and the inner peripheral side of which is closely adhered or pressed to the outer peripheral side of the end of the lighting circuit section. And is provided. As a result, when the attitude of the reflector changes, the sealing means can be easily deformed to follow the change, and the close contact state with the lighting circuit section can be maintained. Therefore, while surely maintaining the airtightness inside the lamp housing, a part of the lighting circuit section fixed to the reflector is exposed to the outside and cooled by the air flow of the outside air to suppress the internal temperature rise of the lighting circuit section. The heat load on the element can be reduced.

In the vehicle headlamp according to the second aspect of the present invention, the inner peripheral side of the seal member is configured to be in pressure contact with the member that is closely fixed to the lighting circuit section. Generally, the lighting circuit section is formed in a substantially rectangular parallelepiped shape. For this reason, when the sealing member comes into pressure contact with the outer periphery of the lighting circuit portion, it may be difficult to maintain a good contact state of the sealing member at each ridge. Therefore, if the member is brought into close contact with the lighting circuit portion and the surface of the member is formed into a smooth curved surface, the close contact between the surface of the member and the seal member can be maintained well.

The vehicle headlight according to claim 3 of the present invention is provided with an actuator, and the reflector is moved by the actuator. That is, in a vehicle headlamp having a leveling mechanism for moving the reflector to maintain the optical axis of the headlamp in a predetermined direction when the vehicle posture changes due to changes in personnel arrangement in the vehicle or load conditions for luggage. In addition, while maintaining the airtightness inside the lamp housing securely, a part of the lighting circuit part fixed to the reflector is exposed to the outside and cooled by the external air flow to suppress the temperature rise inside the lighting circuit part, and the circuit element It is possible to reduce the heat load to the.

In the vehicle headlamp according to a fourth aspect of the present invention, a heat radiation member formed of a material having high thermal conductivity is fixed to the lighting circuit portion, and sealing means is closely fixed to the heat radiation member. Alternatively, it is configured to be pressed into contact. As a result, the outer peripheral shape of the heat dissipation member can be optimized, the adhesion between the heat dissipation member and the sealing means can be improved, and the airtightness of the lamp housing can be reliably maintained.

In the vehicle headlamp according to a fifth aspect of the present invention, the lighting circuit portion is provided with a radiation fin exposed to the outside through the opening of the lamp housing. Accordingly, the lighting circuit unit can be effectively cooled by the air flow of the outside air.

In the vehicle headlamp according to a sixth aspect of the present invention, the heat radiation member is provided with a heat radiation fin exposed to the outside through the opening of the lamp housing. Accordingly, the lighting circuit unit can be effectively cooled by the air flow of the outside air.

In the vehicle headlamp according to claim 7 of the present invention, the sealing means is composed of a plurality of parts. This makes it possible to optimize the shape of the inner peripheral side of the sealing means, improve the adhesion between the lighting control circuit and the sealing means, and reliably maintain the airtightness of the lamp housing.

In the vehicle headlamp according to the present invention, the surface of the lighting circuit portion or the surface of the heat radiating member is exposed to the outside of the lamp housing for air cooling to reduce the heat load on the circuit element, but the surface of the lighting circuit portion. Alternatively, the surface of the heat dissipation member is still hot. Therefore, in the vehicle, when a component arranged near the vehicle headlamp, such as an electric wire or various pipes, comes into contact with the surface of the lighting circuit portion or the surface of the heat dissipation member exposed to the outside of the lamp housing, these components are May be damaged by heat. Therefore, in the vehicle headlamp according to the eighth aspect of the present invention, the cover that covers the lighting circuit portion or the portion exposed from the opening of the heat dissipation member and is permeable to air is fixed to the lamp housing. As a result, while cooling the surface of the lighting circuit unit or the surface of the heat dissipation member, it is possible to prevent the parts around the vehicle headlight from touching the surface of the lighting circuit unit or the surface of the heat dissipation member, and It can be prevented from being damaged by heat.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below based on the embodiments shown in the drawings. In each figure, the same components are designated by the same reference numerals.

(First Embodiment) FIG. 1 shows a first embodiment of the present invention.
FIG. 3 is a sectional view of the vehicle headlamp 1 according to the embodiment. When the vehicle headlamp 1 is mounted on a vehicle, the left-right direction of the drawing sheet is the vehicle front-rear direction and the up-down direction of the drawing sheet is the vehicle up-down direction. FIG. 2 shows an exploded perspective view of main components of the vehicle headlamp 1.

As shown in FIG. 1, a vehicular headlamp 1 includes a lamp housing 2 integrally having a transparent lens 2a.
A reflector 3 whose surface (on the side of the discharge lamp bulb 4) forms a reflecting mirror, the discharge lamp bulb 4, and the discharge lamp bulb 4
The shade 5, which partially shields the irradiation light so as not to be directly irradiated to the front, the lighting control circuit 8, and the lighting control 8 which is attached to the back surface of the reflector 3.
It is configured by accommodating a holder 6 which is a fixing member for holding and fixing the. In the present embodiment, the lighting control circuit 8 is arranged on the back surface of the reflector 3.

The lamp housing 2 is made of a resin molded body, and as shown in FIG. 1, the transparent lens 2 is provided on the front side of the vehicle.
a is integrally provided. Further, in the lamp housing 2, a reflector 3, a discharge lamp bulb 4 and a lighting control circuit 8 are housed. An opening 2b is provided at a position of the lamp housing 2 corresponding to the lighting control circuit 8. The opening 2b is formed in a substantially circular shape so that the lighting control circuit 8 and the holder 6 for mounting the lighting control circuit 8 on the reflector 3 can pass therethrough, and these parts are formed in the assembly process of the vehicle headlamp 1. Is attached to the reflector 3 in the lamp housing 2 through the opening 2b, and the optical axis adjustment work is performed. Furthermore, even on the vehicle, the discharge lamp bulb 4 can be replaced and the lighting control circuit 8 can be inspected through the opening 2b.
A wall portion 2e protruding toward the outside (right side in FIG. 1) of the lamp housing 2 is provided along the entire periphery of the opening portion 2b. The wall portion 2e is fitted and fixed in close contact with a first groove portion 9a provided in the diaphragm 9 described later.

The discharge lamp bulb 4 has, on one end side of the light emitting portion 4a, a flange portion 4b held by the reflector 3 and a male connector 4c for electrically connecting to the lighting control circuit 8. .

The shade 5 for partially blocking the light emitted from the discharge lamp bulb 4 is made of a metal material, and has a substantially hemispherical cap portion 5a and one end that supports the cap portion 5a and the other end that reflects the reflector 3. And a support portion 5b fixed to. The umbrella portion 5a is arranged so as to cover the front side of the discharge lamp bulb 4, and blocks the component of the emitted light of the discharge lamp bulb 4 that is directly radiated forward. As a result, the light emitted toward the front of the vehicle is only the light reflected by the reflector 3, and the vehicle light distribution pattern defined by the reflector 3 can be obtained. Further, the umbrella portion 5a exerts an effect of blocking electromagnetic wave noise directly radiated forward from the discharge lamp bulb 4.

The reflector 3 has a concave reflecting mirror 3a formed on the front side thereof, and a holding portion 3d for holding the discharge lamp bulb 4 formed in the center thereof. The reflector 3 is entirely made of a metal material, or is made of a combination of two or more kinds of materials such as a non-metal material such as a resin material and a metal material. As the reflector 3 made of a combination of a non-metal material and a metal material, for example, there is one in which an aluminum metal film is vapor-deposited on the surface of a resin material. In order for the vehicular headlamp 1 to exhibit a predetermined function, the discharge lamp bulb 4 (specifically, the light emitting section 4a) needs to be arranged at a predetermined position with respect to the reflecting mirror 3a. The flange portion 4b of the discharge lamp bulb 4 is inserted into the holding portion 3d, and the end face of the flange portion 4b on the light emitting portion 4a side is brought into contact with the positioning stopper portion 3e, so that the discharge lamp bulb 4 has the reflecting mirror 4a.
Is accurately held in a predetermined positional relationship with respect to. And
The reflector 3 is configured so that the emitted light of the discharge lamp bulb 4 is reflected forward by the reflecting mirror 3a to obtain a predetermined vehicle light distribution pattern. On the other hand, a mounting surface 3c for fixing the holder 6 is provided on the back surface side of the reflector 3. A lighting control circuit 8 described later is attached to the holder 6. That is, the lighting control circuit 8 is fixed to the back surface side of the reflector 3 via the holder 6.

A lighting control circuit 8 which is a lighting circuit portion for driving the discharge lamp bulb 4 to light up has a built-in electric circuit in a substantially rectangular parallelepiped case 81. This electric circuit is a direct current from a battery (not shown). It is composed of a converter unit that boosts the voltage, an inverter unit that converts a DC voltage into an AC voltage, an igniter unit that generates a high voltage required for lighting start, and the like.
The electric power control for lighting the discharge lamp bulb 4 is performed. The lighting control circuit 8 is attached to the holder 6,
This holder 6 is fixed to the back side of the reflector 3.
Further, the lighting control circuit 8 has a female connector 8c built therein,
It is directly connected to the discharge lamp bulb 4 through the connector 8c without using lead wires. A lead wire 8a having a connector 8b at its tip extends from the lighting control circuit 8, and electric power is supplied to the lighting control circuit 8 from a battery (not shown) by the lead wire 8a. Further, it has a mounting hole 8d for fixing the lighting control circuit 8 to the holder 6.

The lighting circuit section means the entire lighting control circuit 8 including the converter section, the inverter section, and the igniter section, or the igniter section, and means a circuit configuration including at least the igniter section.

The case 81 of the lighting control circuit 8 is made of a material having good thermal conductivity, for example, aluminum. The side of the case 81 opposite to the reflector 3 (right side of FIG. 1)
The end surface 81a is provided with a wall portion 81b that projects toward the outside (right side in FIG. 1) of the lamp housing 2 along the entire periphery of the end surface 81a. This wall portion 81b is fitted and fixed in close contact with a second groove portion 9b provided in the diaphragm 9 described later. Further, inside the wall portion 81b of the end face 81a, a radiation fin 81 for cooling the lighting control circuit 8 is provided.
c is provided. The fin 81c is exposed from the lamp housing 2 when the vehicle headlamp 1 is completely assembled. That is, since the lighting control circuit 8 is exposed to the outside air, the lighting control circuit 8 can be effectively cooled.

The holder 6, which is a fixing member for mounting the lighting control circuit 8 on the reflector 3, is made of resin or metal and has a hole 6a corresponding to the mounting surface 3c of the reflector 3, and this hole is formed. Reflector 3 via 6a
It is fixed to the mounting surface 3c of (1) by screwing. Further, a spring 7 for pressing and fixing the discharge lamp bulb 4 toward the reflector 3 is rotatably held in the holder 6, and a locking portion for locking the tip end portion 7a of the spring 7 is held. 6b is provided. Further, the holder 6 has a female screw hole 6c for fixing the lighting control circuit 8.

The diaphragm 9 which is a sealing means for keeping airtightness between the lamp housing 2 and the lighting control circuit 8 while exposing a part of the lighting control circuit 8 to the outside of the lamp housing 2 has flexibility. The rubber or resin material is formed into a substantially annular shape. In FIG. 3, the diaphragm 9
FIG. As shown in FIG. 3, a first groove portion 9a is provided on the outer peripheral side of the bellows portion 9c of the diaphragm 9, and a second groove portion 9b is provided concentrically on the inner peripheral side thereof. Then, the first groove portion 9a is the wall portion 2c of the lamp housing 2.
In addition, the second groove 9b is provided on the wall 81b of the lighting control circuit 8.
The lamp housing 2 is fitted and closely fixed to the lamp housing 2 respectively.
The airtightness inside is secured.

Next, a method of assembling the vehicle headlamp 1 according to the first embodiment of the present invention will be described.

By this time, the reflector 3 has already been incorporated in the lamp housing 2, and the shade 5 has been attached to the reflector 3. Further, the cover 2c of the lamp housing 2 is removed.

Next, the holder 6 is fixed to the mounting surface 3c of the reflector 3 by screwing. A spring 7 is already rotatably attached to the holder 6.

Next, the discharge lamp bulb 4 is attached to the reflector 3. The flange portion 4b of the discharge lamp bulb 4 is inserted into the holding portion 3d of the reflector 3 while being fitted to the flange portion 4b.
The end surface of the light emitting portion 4a on the side b is brought into contact with the positioning stopper portion 3e. Then, when the tip portion 7a of the spring 7 is locked to the locking portion of the holder 6 while the spring 7 is in contact with the flange portion 4b, the discharge lamp bulb 4 is pressed and fixed to the reflector 3.

Next, the lighting control circuit 8 is attached to the reflector 3. At this time, the female connector 8c of the lighting control circuit 8
Is inserted into the male connector 4c of the discharge lamp bulb 4 and then fixed to the female screw hole 6c of the holder 6 by screwing through the mounting hole 8d.

Next, the lamp housing 2 is opened from the opening 2b.
Diaphragm 9 is used to prevent water and foreign matter from entering the inside.
The first groove 9a in the wall 2 of the lamp housing 2.
c, and the second groove 9b in the wall 81 of the lighting control circuit 8.
Install while fitting and closely fixing to b.

Finally, the reflector 3 is moved while power is supplied to the lighting control circuit 8 to light the discharge lamp bulb 4, and the optical axis is adjusted so that the desired irradiation direction is obtained.

Here, the opening 2b of the lamp housing 2
The shape of the gap between the lamp housing 2 and the lighting control circuit 8 in (1) differs depending on the product due to dimensional variations of the components and the above-described optical axis adjustment work. However, since the diaphragm 9 is made of a flexible material and has the bellows portion 9c that can be easily deformed, the lamp housing 2 and the lighting control circuit 8 can easily respond to the above-described variation in the gap shape. The airtightness between and can be reliably maintained.

In the vehicular headlamp 1 according to the first embodiment of the present invention described above, the lighting control circuit 8 attached to the reflector 3 is opened in the lamp housing 2 opposite to the lighting control circuit 8. End face 81 of case 81
The opening 2b that exposes a to the outside and a substantially annular material made of a flexible material, and the outer peripheral side of the opening 2b is closely fixed to the entire periphery of the opening 2b, and the inner peripheral side of the end surface 81a of the case 81. The diaphragm 9 is provided on the outer peripheral side of the end portion so as to be tightly fixed or pressed. As a result, the end surface 81a of the case 81 of the lighting control circuit 8 fixed to the reflector 3 can be exposed to the outside and cooled by the air flow of the outside air, so that the internal temperature rise of the lighting control circuit 8 can be suppressed and heat to the circuit elements can be suppressed. The load can be reduced.

Further, even when the posture of the lighting control circuit 8 fixed to the reflector 3 changes together with the reflector 3 due to the optical axis adjustment work or the like, the diaphragm 9 made of a material having flexibility can easily be installed in the lighting control circuit 8. Since the posture change can be followed, the airtightness of the lamp housing 2 can be reliably maintained.

(Second Embodiment) FIG. 4 shows a second embodiment of the present invention.
FIG. 3 is a sectional view of the vehicle headlamp 1 according to the embodiment.

In the second embodiment, when the posture of the vehicle changes due to changes in the personnel arrangement in the vehicle or the loading conditions of luggage, the reflector 3 is moved by the actuator and the optical axis of the headlight is always maintained in a predetermined direction. It has a so-called leveling mechanism.

In this leveling mechanism, one rod-shaped support portion 51 for swingably supporting the reflector 3 in the direction of the circular arc arrow A in FIG. 4 and the other rod-shaped support portion that supports the reflector 3 and is movable. The movable portion 52 and a step motor 53, for example, as an actuator for driving the movable portion in the direction of arrow B in FIG. Therefore, the movable portion 52 is driven by the step motor 53 in the direction of arrow B in FIG.
1, the reflector 3 rotates in the direction of the arc arrow A in FIG. 4, so that the vehicle headlamp 1
The optical axis direction of is adjusted.

The operation of this leveling mechanism will be briefly described.

In a vehicle (not shown) in which the optical axis direction of the vehicle headlight 1 is adjusted to a predetermined direction, when luggage is loaded on the rear part of the vehicle, the rear part of the vehicle is lowered and the optical axis direction changes upward. Giving glare to oncoming vehicles. Then, the step motor 53 operates to move the movable portion 52 to the right in FIG. 4, and the reflector 3 rotates counterclockwise in FIG. 4 about the fulcrum 51a to be in the state shown in FIG.
As a result, the optical axis direction of the vehicle headlamp 1 moves downward and is adjusted in a predetermined direction. At this time, as shown in FIG. 5, the upper side of the diaphragm 9 contracts and the diaphragm 9
The lower side extends and the airtightness of the lamp housing 2 is reliably maintained.

When the luggage is unloaded from this state, the rear part of the vehicle rises and the posture of the vehicle returns to its original state, and the distant visibility of the driver decreases because the optical axis direction changes downward.
Then, the step motor 53 operates to move the movable portion 52 to the left in FIG. 5, and the reflector 3 rotates clockwise around the fulcrum 51a in FIG. 5 and returns to the state shown in FIG. As a result, the optical axis direction of the dual-use headlamp 1 moves upward and is adjusted in a predetermined direction.

Here, the change in the attitude of the vehicle can be detected, for example, by detecting the amount of relative displacement between the front wheel axle and the rear wheel axle of the vehicle and the vehicle body.

Usually, the reflector 3 using a leveling mechanism
The rotation angle range of is larger than the rotation angle range of the reflector 3 at the time of adjusting the optical axis in the assembling process of the vehicle headlamp 1, and therefore, the variation amount of the position of the lighting control circuit 8 with respect to the opening 2b is also large.

However, even in the second embodiment, the first
As in the case of the above embodiment, since the diaphragm 9 formed of a flexible material can easily follow the variation, the airtightness of the lamp housing 2 is surely maintained,
It is possible to expose the end surface 81a of the case 81 of the lighting control circuit 8 to the outside and cool it by the air flow of the outside air to suppress the internal temperature rise of the lighting control circuit 8 and reduce the heat load on the circuit elements.

Although the step motor 53 is used as an actuator for rotating the reflector 3 in the second embodiment described above, other actuators such as a DC motor or a linear solenoid may be used.

(Third Embodiment) FIG. 6 shows a second embodiment of the present invention.
FIG. 3 is a sectional view of the vehicle headlamp 1 according to the embodiment.

In the second embodiment, the sealing means is composed of a plurality of parts. That is, the diaphragm 9, the cover 10, and the O-ring 11 are included.

The cover 10 is integrally formed of resin in a substantially annular shape, and the outer peripheral portion thereof has a wall portion 10a projecting toward the outside (right side in FIG. 1) of the lamp housing 2 over the entire circumference.
Is provided. This wall portion 10a is a diaphragm 9
The first groove portion 9a provided in the above is fitted and closely fixed.
Further, a groove portion 10b for holding the O-ring 11 is provided on the entire inner circumference.

A method of assembling the vehicle headlamp 1 according to the third embodiment will be briefly described.

An O-ring 11 is provided in the groove 10b of the cover 10.
After mounting, the cover 10 is fitted on the outer periphery of the lighting control circuit 8. That is, while maintaining the airtightness between the lighting control circuit 8 and the cover 10 by the O-ring 11, the cover 10
Are integrally fixed to the lighting control circuit 8.

Next, the diaphragm 9 is attached while the first groove portion 9a is fitted into the wall portion 2c of the lamp housing 2 and the second groove portion 9b is fitted into and closely fixed to the wall portion 10a of the cover 10, respectively. Assembly of the vehicle headlamp 1 is completed.

Also in the vehicle headlamp 1 according to the third embodiment described above, regarding the cooling of the lighting control circuit 8 and the airtightness maintenance of the lamp housing 2, the same effects as in the case of the first embodiment are obtained. Is obtained.

From the standpoint of workability of mounting the diaphragm 9, it is desirable that the diaphragm 9 has an annular shape or a shape that is as close as possible to the annular shape. The opening 2b of the lamp housing 2 is formed in a substantially circular shape.
On the other hand, the lighting control circuit 8 is usually formed in a substantially rectangular parallelepiped shape, and in order to enhance heat dissipation, that is, to maximize the exposed area, the wall 81b of the lighting control circuit 8 is substantially rectangular (each corner is small. It is formed in an arc shape). Therefore, the workability of mounting the diaphragm 9 may be problematic. However, in the third embodiment, instead of the wall portion 81a of the lighting control circuit 8, the wall portion 1 is provided on the cover 10.
0a is provided and is fitted in the second groove 9 of the diaphragm 9, it is possible to easily form the wall 10a in a circular shape or a substantially circular shape.
The workability of mounting the diaphragm 9 can be improved.

(Fourth Embodiment) FIG. 7 shows a fourth embodiment of the present invention.
FIG. 3 is a sectional view of the vehicle headlamp 1 according to the embodiment.

In the fourth embodiment, the heat dissipation plate 12 which is a heat dissipation member made of a material having high thermal conductivity is attached to the lighting control circuit 8.

The heat dissipation plate 12 is made of a material having high thermal conductivity,
For example, it is formed of a metal such as aluminum. The heat radiating plate 12 is tightly fixed to the end face 81a of the lighting control circuit 8 by screwing or the like so that heat can be transferred. Heat sink 1
A wall portion 12a that projects toward the outside (right side in FIG. 7) of the lamp housing 2 is provided on the entire outer peripheral portion of the lamp housing 2. The wall portion 12a is fitted and fixed in close contact with the first groove portion 9a provided in the diaphragm 9. Further, the heat dissipation plate 12 is provided with heat dissipation fins 12b to enhance heat dissipation efficiency.

In the vehicle headlamp 1 according to the fourth embodiment described above, the same effects as in the case of the first embodiment can be obtained with respect to the cooling of the lighting control circuit 8 and the airtightness maintenance of the lamp housing 2. To be

Furthermore, also in the vehicle headlamp 1 according to the fourth embodiment, it is possible to easily form the shape of the wall portion 12a of the heat dissipation plate 12 into a circular shape or a substantially circular shape. As in the case of the above embodiment, the workability of mounting the diaphragm 9 can be improved.

(Fifth Embodiment) FIG. 8 shows a fifth embodiment of the present invention.
FIG. 3 is a sectional view of the vehicle headlamp 1 according to the embodiment.

FIG. 9 is a view on arrow IX in FIG.

In the fifth embodiment, as shown in FIG.
The shaping cover 1 which is a member in the case 81 of the lighting control circuit 8
3 is tightly fixed, and the surface of the shaping cover 13 is pressed and brought into contact with the diaphragm 14 as a sealing means.

The shaping cover 13 is made of metal or a resin material having excellent heat resistance, and its outer surface is formed into a smooth curved surface as shown in FIG. The diaphragm 14 is made of a flexible rubber or resin material and includes a closed hollow tube 14a.

In the vehicle headlamp 1 according to the fifth embodiment, by mounting the shaping cover 13 on the case 81, the diaphragm 14 is pressed against the smooth curved surface of the shaping cover 13, and It does not touch the four ridge portions 81d of 81. As a result, it is possible to eliminate the possibility of the diaphragm contact failure in the ridge line portion 81d and to reliably maintain the airtightness inside the lamp housing 2.

Further, the tube 14a is easily deformable, and follows well the posture change of the lighting control circuit 8 due to the optical axis adjusting operation, that is, along with the posture change of the lighting control circuit 8, the shaping cover 13 and While changing the contact position of the diaphragm 14 (in this case, forming a closed curved line shape),
Airtightness between the diaphragm 14 and the shaping cover 13 can be favorably maintained.

The outer peripheral side of the diaphragm 14 is closely fixed to the opening 2b of the lamp housing 2,
The inner peripheral side only comes into pressure contact with the shaping cover 13. Therefore, the workability of assembling the vehicle headlamp 1 can be improved.

The vehicle headlamp 1 according to the sixth embodiment can be applied regardless of the presence or absence of the leveling mechanism shown in FIGS. 4 and 5, but in the vehicle headlamp 1 having the leveling mechanism. , Can be more effective.

In the vehicle headlamp 1 according to the sixth embodiment, the diaphragm 14 may have a cross-sectional shape as shown in FIG. 10, that is, a shape having a lip 14b instead of the tube 14a. In this case, the lip 14b may be deformed without changing the contact position of the lip 14b on the shaping cover 13 with respect to the change of the attitude of the lighting control circuit 8, or the lip 14b on the shaping cover 13 may be deformed.
The lip 14b may be deformed as the contact position of b is moved.

(Sixth Embodiment) FIG. 11 shows a sectional view of a vehicle headlamp 1 according to a sixth embodiment of the present invention.

FIG. 12 is a view on arrow XII in FIG.

In the sixth embodiment, as shown in FIG. 11, a protective cover 15 that covers the portion exposed from the opening 2b of the lighting control circuit 8 and is a ventable cover is fixed to the lamp housing 2. .

The protective cover 15 is made of a metal or resin material and has a vent hole 15a.

In the vehicle headlamp 1 according to the present invention, by exposing the lighting control circuit 8 to the outside of the lamp housing and air-cooling, the heat load acting on the circuit element of the lighting control circuit 8 is less than the allowable limit of the circuit element. However, the surface of the case 81 of the lighting control circuit 8 is still hot. Therefore, in the vehicle, parts disposed near the vehicle headlamp 1, such as various electric wires or various pipes, may come into contact with the surface of the case 81 and be damaged by heat.

In the vehicle headlamp 1 according to the sixth embodiment described above, the protective cover 15 can prevent various electric wires or various pipes from coming into contact with the surface of the case 81.

Further, the shape of the ventilation hole 15a provided in the protective cover 15 is such that parts arranged near the vehicle headlamp 1, such as various electric wires or various pipes, cannot invade and the lighting control circuit 8 is cooled. It is set so that the necessary air flow can be passed. Therefore, the cooling action of the outside air on the surface of the case 81 of the lighting control circuit 8 is protected by the protective cover 15.
Not be hindered by.

In the vehicle headlamp 1 according to the sixth embodiment described above, as shown in FIGS. 11 and 12, the protective cover 15 has a plate shape. However, the protective cover 15 is not limited to a plate shape, and may have a mesh shape. Alternatively, it may be in a lattice shape in which thin rods are combined.

In the first to sixth embodiments of the present invention described above, the lighting control circuit 8 is formed as a single component, but it may be divided into a plurality of parts. . For example, it is divided into an igniter part and a converter part + inverter part, the igniter part is fixed to the reflector 3, and the converter part + inverter part is fixed to the lamp housing 2.
The structure may be such that the igniter section and the converter section + inverter section are connected to each other by electric wires while being fixed in an appropriate place.

In the above-described first to sixth embodiments of the present invention, the lighting control circuit 8 inserts the male connector 4c of the discharge lamp bulb 4 into the female connector 8c. Therefore, the lighting control circuit 8 and the discharge lamp bulb 4 can be detached after the connection, but the lighting control circuit 8 and the discharge lamp bulb 4 are permanently connected (for example, by brazing). , Welding, crimping, etc.).

The shape of the attachment portion between the diaphragm 9 and the opening 2b may be the shape shown in FIG. According to this, when the diaphragm 9 is deformed following the posture change of the reflector 3, the diaphragm 9 is opened.
This makes it possible to hold it with difficulty.

[Brief description of drawings]

FIG. 1 is a vehicle headlamp 1 according to a first embodiment of the present invention.
FIG.

FIG. 2 is a vehicle headlamp 1 according to a first embodiment of the present invention.
FIG. 3 is an exploded perspective view of main components of FIG.

FIG. 3 is a vehicle headlamp 1 according to a first embodiment of the present invention.
It is an expanded sectional view of the diaphragm 9 of FIG.

FIG. 4 is a vehicle headlamp 1 according to a second embodiment of the present invention.
FIG.

FIG. 5 is a vehicle headlamp 1 according to a second embodiment of the present invention.
4 is a vertical cross-sectional view after the optical axis is adjusted by the leveling mechanism of FIG.

FIG. 6 is a vehicle headlamp 1 according to a third embodiment of the present invention.
FIG.

FIG. 7 is a vehicle headlamp 1 according to a fourth embodiment of the present invention.
FIG.

FIG. 8 is a vehicle headlamp 1 according to a fifth embodiment of the present invention.
FIG.

9 is a view on arrow IX in FIG.

FIG. 10 is a cross-sectional view showing a modified example of the diaphragm 14 according to the fifth embodiment of the present invention.

FIG. 11 is a partial sectional view of a vehicle headlamp 1 according to a sixth embodiment of the present invention.

12 is a view on arrow XII in FIG.

FIG. 13 is an enlarged partial cross-sectional view showing a modified example of the shape of the attachment portion of the diaphragm 9 with the opening 2b of the present invention.

[Explanation of symbols]

1 Vehicle headlights 2 lamp housing 2a lens 2b opening 2c wall 3 reflector 3a reflector 3c Mounting surface 3d holding part 3e Stopper part 4 discharge lamp bulb 4a light emitting part 4b Flange part 4c connector 5 shades 6 holder 6a hole 6b Locking part 6c Female screw hole 7 spring 7a tip 8 Lighting control circuit (lighting circuit section) 8a lead wire 8b connector 81 cases 81a end face 81b wall 81c Heat dissipation fin 81d Ridge 9 Diaphragm (seal means) 9a First groove part 9b Second groove 9c bellows 10 Cover (seal means) 10a wall 10b groove 11 O-ring (seal means) 12 Heat dissipation plate (heat dissipation member) 12a wall 12b Heat dissipation fin 13 Orthopedic cover (member) 14 Diaphragm (seal means) 14a tube 14b lip 15 Protective cover (cover) 15a vent 51 holding part 51a tip 52 Moving part 53 Step motor (actuator) A circular arrow (rotating direction of reflector 3) B arrow (moving direction of movable part 52)

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) F21V 14/04 F21M 3/20 Z // F21W 101: 10 F21Y 101: 00 (72) Inventor Masayuki Takiguchi Kariya city, Aichi prefecture 1-chome Showa-cho, Denso Co., Ltd. (72) Inventor Kenji Yoneima 1-1-chome Showa-cho, Kariya City, Aichi Prefecture F-term in DENSO Co., Ltd. CC09

Claims (8)

[Claims] 1. A discharge lamp bulb, a reflector for reflecting light emitted from the discharge lamp bulb toward the front, a lighting circuit unit for lighting and driving the discharge lamp bulb, the discharge lamp bulb, the reflector, and A lamp housing for accommodating the lighting circuit section therein, wherein the lighting circuit section is fixed to a back surface of the reflector and is directly connected to the discharge lamp bulb, wherein the lighting circuit is provided. An opening that is opened in the lamp housing on the side opposite to the opening and that exposes the end of the lighting circuit section to the outside, and is formed in a substantially annular shape with a flexible material, the outer peripheral side of which is the entire peripheral edge of the opening. A vehicle provided with a sealing means that is closely fixed to the circumference and whose inner circumferential side is tightly fixed or press-contacted to the outer circumferential side of the end portion of the lighting circuit section. Headlight. 2. The vehicle headlamp according to claim 1, wherein an inner peripheral side of the seal member is in pressure contact with a member that is closely fixed to the lighting circuit unit. 3. The vehicle headlamp according to claim 1 or 2, further comprising an actuator, wherein the reflector is moved by the actuator. 4. A heat radiation member formed of a material having high thermal conductivity is fixed to the lighting circuit portion, and the sealing means is closely fixed or pressed to the heat radiation member. The vehicle headlamp according to any one of claims 1 to 3. 5. The vehicle headlamp according to claim 1, wherein the lighting circuit portion is provided with a radiation fin exposed to the outside through the opening. 6. The vehicle headlamp according to claim 4, wherein the heat dissipation member is provided with a heat dissipation fin exposed to the outside through the opening. 7. The vehicle headlamp according to claim 1, wherein the sealing means is composed of a plurality of parts. 8. The lamp housing according to claim 1, wherein a cover that covers the lighting circuit portion or a portion of the heat dissipation member exposed from the opening and is permeable to air is fixed to the lamp housing. The vehicle headlamp described in.