JP3148268B2 - Discharge lamp device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge lamp device,
In particular, the present invention relates to a discharge lamp device provided with a discharge lamp having a counter discharge electrode in a closed glass bulb.

[0002]

2. Description of the Related Art As shown in FIG. 4, this type of discharge lamp device has a structure in which both ends of a discharge lamp 5 are supported by a pair of lead supports 3 and 4 protruding from a base 2. The discharge lamp 5 has electrodes 6, 6 opposed to each other in a closed glass bulb 5a at the center of the glass tube. The glass tube has pinch seal portions 5b, 5g for sealing molybdenum foils 7, 7 connected to the electrodes 6, 6. 5b, the pinch seal portion 5
b welded, leads 8 and 8 connected to the molybdenum foil 7,7 is diverted to the outside from 5b, the lead support 3,4 The lead wires 8 and 8 directly or through a metal support 9 Have been. The glass bulb 5a contains a metal halide substance (for example, sodium-thallium-indium or scandium-sodium) other than mercury as a luminescent substance. Reference numeral 1 denotes an ultraviolet shielding glove fixed and held on the base 2, which cuts ultraviolet light in a wavelength range harmless to the human body from emission of the discharge lamp 5.

[0003]

The lead supports 3, 4 for supporting the discharge lamp are also made of metal in consideration of strength and conductivity because they are also current paths for the electrodes 5, 6. When the discharge lamp is turned on, the lead supports 3 and 4 are exposed to ultraviolet rays generated from the discharge section. For this reason, free electrons having negative charges are excited from the inside of the lead support and fly out, and adhere to the surface of the closed glass bulb 5a. Then, the positively charged metal atoms (Na +) in the closed glass sphere 5a are pulled by the negatively charged free electrons attached to the glass sphere, pass through the wall of the glass sphere, and jump out of the glass sphere. For this reason, there has been a problem that the concentration of the luminescent substance in the glass bulb decreases, and the life of the discharge lamp becomes short.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to provide a discharge lamp device which can solve the problems caused by exposure of a lead support to ultraviolet rays.

[0005]

Means for Solving the Problems In order to achieve the above object, in a discharge lamp device according to the present invention, both ends are pinch-sealed, and a discharge portion is provided with an electrode provided substantially at the center in the longitudinal direction of a glass tube. In a discharge lamp device in which at least one end of a discharge lamp having a certain closed glass bulb is supported by a metal lead support protruding from an insulating base, the discharge lamp is sealed in a pinch seal portion to discharge the discharge lamp. It is sealed and integrated into the surrounding ultraviolet shielding glove, and its front end is connected to the lead support.
With the rear end facing the front of the insulating base.
It is configured to be fixedly connected .

[0006]

Since the [action] discharge lamp globe for ultraviolet radiation shielding surrounding the to cut the ultraviolet rays from the light emission of the discharge lamp, the amount of ultraviolet rays bathed the lead support is small, the amount of excited to lead support or hiragana beauty out free electrons is also small. Also, even if the lead support is excited by ultraviolet light and free electrons jump out of the lead support, the free electrons adhere to the ultraviolet shielding glove and cannot access the discharge lamp any more, and the free electrons cause the free electrons inside the sealed glass sphere. The attraction force (energy) acting on the metal atoms constituting the luminescent substance is not large enough to allow the metal atoms to pass through the closed glass sphere wall.

[0007]

Next, an embodiment of the present invention will be described with reference to the drawings. 1 and 2 show a first embodiment of the present invention. FIG. 1 is a perspective view of a discharge lamp device, and FIG. 2 is a longitudinal sectional view of the discharge lamp device. In these figures, the discharge lamp device is provided with a discharge lamp 10, an ultraviolet shielding globe 20 sealed and integrated with the discharge lamp 10, and an insulating base 30. And a lead support 32 for supporting the front end of the integrated discharge lamp / globe.

[0008] The discharge lamp 10 has a rectangular cross-sectional rectangular shape at both ends of an elliptical closed glass sphere 12 forming a discharge space by pinching the front and rear ends of a quartz glass tube having a circular pipe shape. In this structure, a starting rare gas, mercury, and a metal halide (for example, a sodium-thallium-indium luminescent material) are sealed in the glass bulb 12. At the front and rear end portions, a circular pipe-shaped extension portion 14 which is a non-pinch seal portion extending from the pinch seal portions 13a and 13b.
a and 14b are integrally formed. Sealed glass ball 12
Discharge electrodes 15a and 15b made of tungsten are disposed inside the discharge electrodes 15a and 15b, and the discharge electrodes 15a and 15b are molybdenum foils 16a and 16a sealed to pinch seal portions 13a and 13b.
16b, lead wires 18a, 18b connected to the molybdenum foils 16a, 16b are respectively led out from ends of the pinch seal portions 13a, 13b, and lead wires 18
Reference numerals a and 18b extend to the outside through the extending portions 14a and 14b, respectively.

The ultraviolet shielding globe 20 has a glass tube having substantially the same length as the discharge lamp 10 and a diameter larger than the diameter of the discharge lamp 10.
a, 13b and integrated with the discharge lamp 10. That is, the discharge lamp 10 has a structure sealed in the ultraviolet shielding globe 20 made of glass. Code 21
Reference numerals a and 21b denote sealing portions between the globe 20 and the discharge lamp 10. The outer peripheral surface of the globe 20 is coated with an ultraviolet shielding film 22 such as ZnO so as to cut off ultraviolet light in a predetermined wavelength range which is harmful to the human body from light emission in the sealed glass bulb 12 which is a discharge part. On the other hand, the inside of the globe 20 is set in a vacuum state, and has an adiabatic action against radiation of heat from the sealed glass bulb 12 which is a discharge part. That is, when the ultraviolet shielding film 22 is heated to a high temperature (depending on the type of the ultraviolet shielding film, for example, a high temperature exceeding 700 ° C.), the ultraviolet shielding effect is reduced.
Are sealed at pinch seal portions 13a and 13b, which are located at positions away from the high-temperature sealed glass bulb 12 in the front-rear direction of the discharge axis.

[0010] The discharge lamp / globe body in which the globe 20 is sealed and integrated has a rear end engaged with and supported by the front-side engaging recess 31 of the insulating base, and a front end joined to the insulating base 30. It has a structure supported by a pair of long and short metal lead supports 32 that are insert molded and protrude forward from the base. That is, the rear end of the discharge lamp and the rear end of the globe are flush with each other, and the rear end of the globe is inserted into the base-side concave portion 31 and fixed with an adhesive. A lead wire 18b extending from the extension portion 14b penetrates through the front and rear through-holes 33 formed in the insulating base 30 and is welded to a terminal 34 insert-molded in the base 30. The extension 14a, which is the front end of the discharge lamp, protrudes forward from the front end of the globe, and the lead wire 18a extending from the extension 14a is spot-welded to the bent end 32a of the lead support 32. Reference numeral 35
Is a terminal integrated with the lead support 32;
Reference numeral 9 denotes a ceramic disk that is adhered and fixed to the front surface of the base 30.

As described above, since the light transmitted through the ultraviolet shielding film 22, that is, the light in which the ultraviolet light of a predetermined wavelength region has been cut is applied to the lead support 32, the degree of excitation of free electrons in the read support is small. The amount of free electrons jumping out is also small. Even if the lead support 32 is excited by ultraviolet rays and free electrons jump out of the lead support, the free electrons will not
And adheres to the surface of the globe 20 that is sufficiently separated from the closed glass bulb 12. For this reason, the attractive force (energy) acting on the sodium atoms constituting the luminescent substance in the closed glass sphere 12 by free electrons is weak,
There is no problem that sodium atoms are attracted to free electrons and penetrate the closed glass sphere wall as in the related art.

FIG. 3 is a longitudinal sectional view of a discharge lamp device according to a second embodiment of the present invention. In this embodiment, the diameter of the globe region 20 a surrounding the sealed glass bulb 12, which is the highest temperature of the discharge lamp 10, is increased so as to reduce the influence of heat on the ultraviolet shielding film 22 formed on the globe 20. It was done. The other parts are the same as those of the first embodiment, and the description thereof will be omitted by retaining the same reference numerals.

In the above embodiment, the inside of the globe 20 is in a vacuum state. However, a structure in which a rare gas having a heat insulating action is sealed may be used. In the above-described embodiment, the ultraviolet shielding film 22 coated on the globe 20 cuts off the ultraviolet rays. However, the globe 20 itself may be made of a glass having an ultraviolet cutting action, such as hard glass. .

[0014]

As is apparent from the above description, according to the discharge lamp device of the present invention, the globe for shielding ultraviolet rays extends between the lead support and the sealed glass bulb as the discharge portion. Therefore, the amount of ultraviolet rays exposed to the lead support is significantly reduced, and there is no problem that the concentration of the sealing gas in the discharge lamp is reduced by free electrons excited by the ultraviolet rays and jumping out of the lead support. Even if free electrons fly out of the lead support, they adhere to the surface of the glove and cannot approach the closed glass sphere side, so the free electrons exert a small attractive force (energy) on metal atoms in the closed glass sphere. The conventional problem of reducing the life of the discharge lamp without affecting the sealing gas in the discharge lamp is solved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a discharge lamp device according to a first embodiment of the present invention, partially cut away;

FIG. 2 is a longitudinal sectional view of the discharge lamp device.

FIG. 3 is a longitudinal sectional view of a discharge lamp device according to a second embodiment of the present invention.

FIG. 4 is a longitudinal sectional view of a conventional discharge lamp device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Discharge lamp 12 Sealed glass bulb | ball which is a discharge part 13a, 13b Pinch seal part 14a, 14b Extension part 15a, 15b Discharge electrode 18a, 18b Lead wire 20 Ultraviolet shielding glove 22 Ultraviolet shielding film 30 Insulating base 32 Lead support

Claims (1)

(57) [Claims] At least one end of a discharge lamp having a closed glass bulb, which is a discharge section having a pair of electrodes disposed at substantially the center in the longitudinal direction of a glass tube and having both ends pinched and sealed, is made of a metal protruding from an insulating base. In the discharge lamp device supported by the lead support, the discharge lamp is sealed in a pinch seal portion and sealed and integrated in an ultraviolet shielding globe surrounding the discharge lamp.
When the front end of the lamp is supported by the lead support
A discharge lamp device having a rear end directly fixed to the front surface of the insulating base .