JP2010225506A - Vehicular discharge lamp and vehicle headlight using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular discharge lamp and a vehicle headlight capable of recognizing existence of a vehicle at a non-lamplight condition under a night environment in a simple structure. <P>SOLUTION: In the vehicular discharge lamp (1) which is a metal halide lamp having a single base type bulb with a double-tube structure, a lead wire (9) being led from a pointed head of an outer tube (3) is located at a lower side of the cylindrical outer tube (3) arranged inside an arc tube (5), an insulating ceramic tube (10) is covered on the lead wire (9), and a luminous material (11) is arranged in the ceramic tube (10). Furthermore, the vehicle headlight (20) has a rotation paraboloidal reflecting mirror (23), a transparent lens cover (22), and the vehicular discharge lamp (1) in the vicinity of the focus of the reflecting mirror. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a discharge lamp, particularly preferably a double-end type discharge lamp and a vehicle headlamp using the same.

In a vehicular lamp, particularly a headlamp, at least two light distribution patterns, that is, a light distribution pattern of a traveling beam (high beam) and a light distribution pattern of a passing beam (low beam) are required. Also, a front combination lamp is generally used in which lamps such as a direction indicator lamp and a vehicle width lamp are provided in one housing and these are mounted on the vehicle. Further, a position bulb function is often provided by providing a position bulb for the headlamp.
By lighting the position valve, other companies can be informed of the existence of automobiles even at night.

In a dark environment such as at night, there is also a method of making a license plate shine as a method for making it possible to confirm the presence of an automobile even when a vehicular lamp is turned off (see Patent Document 1).
According to Patent Document 1, the letters written on the license plate are formed by cutting out a tape coated with a phosphorescent paint, and the tape is overlaid on the corresponding letters so that the letters are stored by sunlight in the daytime. Will also emit light.

In addition, a method has been proposed in which the presence of an automobile can be confirmed even when the vehicular lamp is turned off in a dark environment such as at night by providing a phosphorescent paint on the vehicular lamp instead of the license plate.
For example, in the vehicular lamp of Patent Document 2, a light guide path is provided in a range that does not hinder the light distribution characteristics of the vehicular lamp, specifically, a position around the projection lens of the project type lamp, and the projection lens is formed on the surface of the light guide path. Describes a vehicular lamp in which a phosphorescent paint is provided at a position around the.

JP 2001-191865 A JP 2007-149435 A

  However, in Japanese Patent Laid-Open No. 2004-260260, characters that match the number plate are necessary, and thus many characters must be facilitated in order to deal with a large number of automobiles. Moreover, since it is mainly stored by daytime sunlight, it had to maintain the self-luminous effect for a long time from dark to bright.

  In Patent Document 2, the above-mentioned problem can be solved by providing a phosphorescent paint on the vehicle lamp, but a light guide path for guiding the emitted light from the light source of the vehicle lamp is newly provided on the phosphorescent paint. It is necessary, the number of parts increases, and the mechanism of the vehicle lamp becomes complicated.

  The present invention has been made in view of such circumstances, and the problem to be solved is a discharge lamp for a vehicle that can recognize the presence of a vehicle even in a no-light condition in a nighttime environment with a simple configuration. And a vehicle headlamp.

The above object can be achieved by the following embodiments.
The invention according to claim 1 is a space (5) having a dissociation product of metal vapor and halide inside, and a pair of discharge electrodes (6) disposed so as to face each other with the tip protruding into the space (5). An arc tube (2) comprising:
A lead wire (9) electrically connected to each discharge electrode (6) through both ends of the arc tube (2);
A cylindrical outer tube (3) having an arc tube (5) provided therein;
A base (4) having a power feeding terminal (43, 44) connected to the lead wire (9) inside and fixing the outer tube,
An insulating ceramic tube (10) that covers the lead wire led out from the end portion between the base (4) and the distal end portion of the outer tube, on the lower side of the outer tube;
The ceramic tube (10) is a vehicular discharge lamp (1), wherein a phosphorescent material (11) is provided.

  According to the present invention, since the ceramic tube 10 located near the space portion 5 serving as the light emitting portion is provided with the phosphorescent material 11, it is possible to effectively accumulate light by turning on the vehicle discharge lamp. In addition, at the time of non-lighting such as at night, light accumulated by lighting is radiated from the vicinity of the light emitting unit. Therefore, it is possible to illuminate with a light distribution characteristic approximate to that when the light source is turned on.

In the vehicle discharge lamp of the present invention, it is preferable to provide a luminous layer (15) around the arc tube insertion hole (45) of the base (4).
By providing the phosphorescent layer on the base surface around the arc tube insertion hole, when the vehicle discharge lamp is turned on, the phosphorescent layer can be efficiently stored. The ceramic tube 10 positioned below the arc tube 2 is positioned in the horizontal direction, but the phosphorescent layer 15 extends in the vertical direction perpendicular to the ceramic tube 10 and is positioned near the space portion 5. Therefore, at the time of non-lighting, such as at night, the light accumulated by lighting is radiated from the vicinity of the light emitting unit, and is observed in a three-dimensional shape to improve visibility.

Furthermore, in the vehicle discharge lamp of the present invention, it is preferable that the ceramic tube (10) is a sintered body of a phosphorescent material and an inorganic ceramic.
By using a sintered body, the phosphorescent material does not fall off due to vehicle vibration or the like. Thereby, the discharge lamp for vehicles excellent in vibration resistance can be obtained.

According to another aspect of the present invention, a housing (21) that opens forward, a lens cover (22) that covers a front opening of the housing (21), the housing (21), and a lens cover (22) A light source (1) and a reflecting mirror (23) located in the space surrounded by
A vehicle headlamp (20), wherein the light source (1) is the above-described vehicle discharge lamp.

  According to the above aspect of the invention, since the ceramic tube 10 located near the space 5 serving as the light emitting portion is provided with the phosphorescent material 11, the light distribution characteristics of the headlamp when the light source is turned on and the light source is turned off. The light distribution characteristics in the are approximated, and the visibility of the headlamps when the lights are turned off is improved.

According to the present invention, light emission by the phosphorescent material can be maintained for a long time without increasing the number of parts. In addition, there is an advantage that it is possible to provide a vehicle discharge lamp and a vehicle headlamp that can recognize the presence of the vehicle even in a no-light condition under nighttime environments.

FIG. 1 is a side view of a discharge lamp for a vehicle according to an embodiment of the present invention. 2 is an explanatory view schematically showing a bottom view (base side) and a front view (light source side) of the vehicle discharge lamp base of FIG. (A) is a bottom view, (b) is a front view. FIG. 3 is a longitudinal sectional view of a vehicle headlamp using a vehicle discharge lamp according to an embodiment of the present invention as a light source. Explanatory drawing which shows the discharge lamp for vehicles which concerns on FIG. 4 other embodiment. (A) is a side view, (b) is a front view.

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to FIGS.
The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. As long as there is no description of the effect, it is not restricted to these aspects.

FIG. 1 shows a side view of a vehicular discharge lamp to which the present invention is applied, and a part of an arc tube and an outer tube are shown in a cross-sectional view for easy understanding.
2 schematically shows a bottom view and a front view of the vehicle discharge lamp of FIG. 1, wherein FIG. 2 (a) is a bottom view and FIG. 2 (b) is a front view. FIG. 3 is a longitudinal sectional view of a vehicle headlamp using a vehicle discharge lamp to which the present invention is applied as a light source.

  As shown in FIG. 1, a vehicular discharge lamp 1 is a single-ended die tube having a double tube structure in which an arc tube 2 is sealed in an outer tube 3 and one end is fixed to a base 4. This is a metal halide lamp with a power of 35 W.

  The arc tube 2 is a translucent container made of quartz glass. The arc tube 2 has a substantially elliptical bulging portion at the center and a substantially oval space portion 5 inside. The space portion 5 serves as a discharge space. Sealing portions 8 formed by crushing glass tubes in a molten state are formed at both ends of the space portion 5. Discharge electrodes 6 and 6 are provided inside the respective sealing portions 8 and 8 so that one end portion protrudes into the space portion 5 and faces the space portion 5. The discharge electrode 6 on the base 4 side is connected to the lead wire 9a via a molybdenum foil in the sealing portion 8 by means such as welding. The other discharge electrode 6 on the tip side is also connected to the lead wire 9b through a molybdenum foil in the sealing portion 8 by means such as welding.

  In the space portion 5, a metal halide and a predetermined rare gas are sealed as a discharge medium. The tips of the discharge electrodes 6 and 6 protruding into the discharge space are made of a refractory metal alloy such as thorium tungsten (tungsten and thorium), and are arranged to face each other at a predetermined discharge interval.

  The outer tube 3 is made of cylindrical quartz glass, and the arc tube 2 is accommodated therein. Both ends of the outer tube 3 are heat-shrinked after the arc tube 2 is accommodated therein, and have a joint portion 7 welded to the end portion of the arc tube 2 accommodated therein. By performing the joint 7 in an airtight manner, the space between the arc tube 2 and the outer tube 3 can be filled with an inert gas such as a rare gas or a vacuum atmosphere can be formed. Moreover, it is good also as the non-airtight junction part 7. FIG.

  The base 4 is made of a heat-resistant insulating synthetic resin material such as polyetherimide or polyphenylamide, and includes a flange portion 41 on the arc tube side and a terminal portion 42 on the opposite side. The terminal portion 42 is provided with one power supply terminal 43 for connection to an external power supply on the side surface and the other power supply terminal 44 on the bottom surface side.

  On the arc tube side of the base 4, an arc tube insertion hole 45 and a tip side lead wire insertion hole 46 for positioning and fixing the arc tube 2 and the outer tube 3 are provided. A metal plate (not shown) for connecting to the power feeding terminal 44 is provided inside the arc tube insertion hole 45, and the base-side lead wire 9a inserted into the arc tube insertion hole 45 is connected to the metal plate. Further, in a state where the arc tube 2 and the outer tube 3 are inserted into the arc tube insertion hole 45, the outer tube 3 and / or the joint portion 7 are attached and fixed by being sandwiched between fixing members (not shown).

The leading end side lead wire 9 a is inserted into the leading end side lead wire insertion hole 46. The distal end side lead wire 9 a is electrically connected at one end to the discharge electrode 6 within the sealing portion 8 and connected at the other end to the power feeding terminal 43 within the distal end side lead wire insertion hole 46. Connected to a metal plate (not shown). Further, the tip-side lead wire 9b is drawn out from the tip of the arc tube 2, and is connected and fixed to the external lead wire 9d by means such as welding. The external lead wire 9d is covered with a cylindrical ceramic tube 10 between the bending point 9c and the leading end side lead wire insertion hole 46.
The leading-end-side lead wire insertion hole 46 is provided at a lower position when the vehicle discharge lamp 1 is provided in the vehicle.

  The ceramic tube 10 contains an insulating ceramic, for example, inorganic particles such as alumina as a main component and a phosphorescent material 11 as a sub-material. As the phosphorescent material 11, an afterglow aluminate phosphor or the like can be used. The ceramic tube 10 containing the phosphorescent material is formed by mixing alumina particles and phosphor particles having a predetermined particle diameter, for example, several tens of μm, and sintering the mixture at a predetermined temperature.

  FIG. 3 shows a vehicle headlamp 20 using the vehicle discharge lamp 1 provided with the ceramic tube 10 containing the phosphorescent material 11 as a light source. The vehicle headlamp 20 includes a housing 21 that opens forward, a lens cover 22 that covers the front opening of the housing 21, a vehicle discharge lamp 1, and a reflecting mirror 23. The lens cover 22 is made of a transparent resin such as polycarbonate. In the space surrounded by the lens cover 22 and the housing 21, a non-projector type headlamp in which the above-described vehicle discharge lamp 1 and the reflecting mirror 23 are arranged is provided. A light distribution characteristic required for a vehicle headlamp is mainly formed by the reflecting mirror 23, and the lens cover 22 is substantially transparent. The reflecting mirror 23 has a focal point S on or near the arc tube. For example, by using a rotary parabolic reflecting surface centered on the focal point S, the light is irradiated forward as a substantially parallel light beam with a desired light distribution characteristic without focusing.

  When the electric discharge lamp 1 for a vehicle having a double-tube structure single-end die tube is connected to a terminal portion 42 of the base 7 connected to a lighting circuit device having a booster circuit or the like and energized, A predetermined voltage is applied to the discharge electrodes 6 and 6 through 43 and 44 and the lead wires 9a and 9d. As a result, a discharge occurs in the space portion 5 to emit light. The light emitted by the discharge is emitted through the arc tube 2 and the outer tube 3 made of a translucent container.

  Part of the emitted light reaches the ceramic tube 10. Since the ceramic tube 10 contains a phosphorescent material, phosphorescence is performed by light emission from the vehicle discharge lamp. Therefore, when the lighting of the vehicle discharge lamp is stopped at night, the phosphorescent material emits light after the stop. That is, the ceramic tube 10 located near the arc tube 2 serves as a light source.

  Accordingly, when the vehicle headlamp 20 is not lit, light is emitted from the phosphorescent material of the ceramic tube 10 located near the focal position S of the reflector 23, and the light is emitted from the reflector 23 by the reflector 23. Irradiated forward. At this time, since the arc tube 2 and the ceramic tube 10 are close to each other, it is possible to obtain a light distribution characteristic approximate to the light distribution characteristic of the vehicle headlamp 20. Therefore, the visibility at night is improved. In particular, when the ceramic tube 10 is provided so as to be positioned directly below the focal position S, the same reflecting mirror 23 is used. Therefore, the light distribution characteristic when the focal position is shifted downward, that is, the distribution of slightly upward light. Light characteristics. Therefore, the visibility from the oblique upper side is also improved.

  In addition, during daytime, sunlight is also stored. Since the arc tube 2 and the ceramic tube 10 are close to each other, the light incident from the outside of the vehicle headlamp 20 is reflected by the reflecting mirror 23, and the amount of light reaching the ceramic tube 10 near the focal position S is also large. It increases compared to the case where it is provided at a location far from other light sources. Therefore, the luminous efficiency at daytime is improved.

  Furthermore, by using the ceramic tube 10 as a sintered body made of a mixture of the phosphorescent material 11 and inorganic ceramics, the phosphorescent material is not dropped even when vibration or impact is applied when the vehicle is mounted on the vehicle. Absent. Therefore, vibration reliability can be easily increased as compared with the case where the phosphorescent material is provided by coating.

FIG. 4 shows a discharge lamp for a vehicle according to another embodiment. In FIG. 4, the same reference numerals as those of the vehicle discharge lamp according to the previous embodiment are given, and the description thereof is omitted. 4A is a side view and FIG. 4B is a front view.
This embodiment is different from the previous embodiment in that the phosphorescent layer 15 is provided so as to surround the arc tube insertion hole 45 on the arc tube side of the base 4. The phosphorescent layer 15 is coated with a paint containing a phosphorescent material on the arc tube side surface of the base 4. The thickness of the phosphorescent layer 15 is greater than 20 μm. If it is thinner than this, the amount of light emission at night will be insufficient, and it tends to be uneven brightness.

  In the vehicle discharge lamp 1, the ceramic tube 10 and the phosphorescent layer 15 contain a phosphorescent material. Therefore, at the time of non-lighting in the dark such as at night, the light storage material contained therein emits light stored in the daytime or the like from both the ceramic tube 10 and the light storage layer 15. Therefore, compared with the light emission only from the ceramic tube 10, a feeling of depth can be improved and it can recognize more three-dimensionally.

  The vehicle discharge lamp and the vehicle headlamp using the same according to the present invention are not limited to the above-described embodiments. For example, in the above-described embodiment, the ceramic tube 10 is a sintered body made of a mixture of a phosphorescent material and inorganic ceramics. However, the ceramic tube 10 may be coated with a phosphorescent material. It goes without saying that various modifications can be made without departing from the scope of the present invention.

  The present invention can be applied to a vehicular discharge lamp including a ceramic tube and a vehicular headlamp using the same.

DESCRIPTION OF SYMBOLS 1 Vehicle discharge lamp 2 Light emission tube 3 Outer tube 4 Base 5 Space part 6 Discharge electrode 7 Joint part 8 Sealing part 9 Lead wire 10 Ceramic tube 11 Phosphorescent material 15 Phosphorescent layer 20 Vehicle headlamp 21 Housing 22 Lens cover 23 Reflector

Claims (4)

An arc tube comprising a space portion having a dissociation product of metal vapor and halide therein, and a pair of discharge electrodes projecting from the tip of the space portion and opposed to each other;
A lead wire electrically connected to each discharge electrode through both ends of the arc tube;
A cylindrical outer tube with an arc tube inside;
A base for fixing the outer tube with a power supply terminal connected to the lead wire inside,
An insulating ceramic tube that covers a lead wire led out from the end portion between the base and the tip end portion of the outer tube and under the outer tube;
A discharge lamp for a vehicle, wherein the ceramic tube is provided with a phosphorescent material.   The vehicular discharge lamp according to claim 1, wherein a phosphorescent layer is provided around the arc tube insertion hole of the base.   The vehicle discharge lamp according to claim 1, wherein the ceramic tube is a sintered body of a phosphorescent material and an inorganic ceramic. A housing with an open front;
A lens cover covering the front opening of the housing;
A light source and a reflecting mirror located in a space surrounded by the housing and the lens cover;
A vehicle headlamp, wherein the light source is the vehicle discharge lamp according to any one of claims 1 to 3.

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