JPH03254060A - Bulb - Google Patents

Abstract

PURPOSE:To provide possibility of refilling naturally exhausted oxygen in the atmosphere under lighting by encapsulating an oxygen emitting substance within an outer tube, and thereby filling the outer tube with oxygen of requisite concen tration. CONSTITUTION:An optical film consisting of metal oxide is provided over at least either of the outside surface of an inner tube 1 and the inside surface of an outer tube of this bulb concerned embodied in double tube construction, and an oxygen emitting substance is encapsulated within the outer tube 1. This liberates necessity for refilling the atmosphereic gas containing oxygen at an exhaustion of m/c if the outer tube 1 is filled with inert gas not containing oxygen at all or if the outer tube 1 is evacuated completely followed by releas ing of oxygen necessary after sealing. Under lighting, naturally exhausted por tion can be refilled by releasing oxygen little by little into the outer tube atmo sphere, so that there is no need to encapsulate too much oxygen at the time of sealing, and further a necessary amount of oxygen can be maintained in the atmosphere in the outer tube for a long period of time.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention provides an optical film made of a metal oxide on at least one of the outer surface of the inner tube and the inner surface of the outer tube of a double-tube type bulb. Among these, the high-temperature durability of the optical film is improved.

(Prior Art) In recent years, reflex lamps, sealed beam lamps, etc., in which the inner tube of a halogen bulb is hermetically sealed inside the outer bulb, have been developed and have become prized for their ability to provide high output. In particular, in recent years, such double-tube halogen light bulbs have been provided with an optical film, such as a visible light-transmissive infrared reflective film, on the outer surface of the inner tube, and in which the inside of the outer tube is evacuated or filled with inert gas. was developed.

Such a visible light transmitting infrared reflective film is made of titanium oxide (Fi
O□), tantalum oxide (TaO□), zirconium oxide (Z
It is made up of 6 to 21 alternate layers of high refractive index layers made of metal oxides such as rOz) and low refractive index layers made of metal oxides such as silica (Sin, ) and selenium oxide (SeO□). By adjusting the layer thickness appropriately, visible light is transmitted through light and infrared rays are reflected using light interference. Due to the action of this visible light transmitting infrared reflective film, the visible light emitted from the filament passes through this reflective film and is radiated to the outside world through the outer tube, and the infrared light is reflected by this reflective film and returns to the filament. Return and heat it up. Therefore, this halogen bulb has the advantage of being highly efficient and emitting so-called cold light with little infrared radiation.

However, since the inner tube of such double-tube halogen bulbs has poor cooling, not only does the temperature of the bulb in the inner tube become extremely high during operation, but the temperature of the sealing part also reaches a level close to the bulb temperature. Rise. As described above, if the inside of the outer tube is kept in a vacuum or in an inert gas atmosphere such as nitrogen or argon, the molybdenum-introduced foil will not be oxidized.

However, as mentioned above, during lighting, the temperature of the inner bulb becomes extremely high.For example, in the reflex lamps and sealed beam lamps mentioned above, the temperature of the outer surface of the bulb of the inner bulb, in other words, the temperature of the visible light transmitting infrared reflective film, is 500 - 800
It can even reach ℃. According to experiments, when a metal oxide film such as titanium oxide, tantalum oxide, or selenium oxide is heated for a long time in direct air or in an inert gas such as pure nitrogen or pure argon, the temperature of the metal oxide film reaches 500%. It has been found that when the temperature exceeds °C, deoxidation development occurs in the metal oxide, and the metal oxide gradually changes to a lower oxide, and finally becomes a reduced metal. When such a deoxidation phenomenon of component metal oxides occurs in the visible light transmitting infrared reflective film of the above-mentioned double tube halogen light bulb, the wavelength range that is transmitted or reflected changes and the desired effect is not achieved. Eventually, the film will turn black and the light output will drop significantly.

In contrast, the inventor of the present invention has developed a double-tube halogen light bulb as described above, in which the inside of the outer bulb is placed in a weakly oxidizing atmosphere, such as a mixture containing an oxygen partial pressure of 0.0076 to 76 Torr and an inert gas partial pressure of 300 to 1520 Torr. By creating a gas atmosphere, there is no risk that the metal oxides that make up the optical film will be deoxidized (reduced) even at high temperatures during lighting.
In addition, he developed a technology to prevent the introduction conductor such as the introduction foil from being deteriorated by oxidation, and applied for this by patent application in 1986.
It was proposed as No. 3-334889.

(Problem to be solved by the invention) As described above, there is an upper limit and a lower limit to the appropriate amount of oxygen concentration in the outer tube atmosphere, and when the upper limit is exceeded, the life of the introduced conductor is shortened, and when the lower limit is below, the optical film Deoxygenation of the metal oxides that make up the metal oxides begins. Furthermore, the oxygen concentration in the outer tube atmosphere gradually decreases during lighting. Furthermore, the appropriate amount of oxygen concentration varies depending on the pipe type, output, and structure. moreover,
During manufacturing, if the oxygen concentration in the outer tube is 3000 pp.
If you try to seal a normal double-tube halogen bulb without a visible light-transmissive infrared reflective film, which is filled with inert gas of 50 ppm or more and then filled with an inert gas with an oxygen concentration of 50 ppm or less in the outer bulb, the switching At this time, it is necessary to perform vacuum cleaning on the exhaust system and air supply system of the exhaust m/c for 10 hours or more to eliminate oxygen adsorbed on the inner surface of the air supply system. This also applies when a plurality of tube types having different appropriate oxygen concentrations in the outer tube atmosphere are sequentially evacuated and atmospheric gases having respective oxygen concentrations are filled in the outer tube.

Therefore, the problem of the present invention is to set the ambient air inside the outer tube under the same conditions regardless of the product type or rating, satisfy the necessary oxygen concentration, and prevent the natural depletion of oxygen in the atmosphere during lighting. The objective is to provide refillable tubes.

[Structure of the invention]

(Means for Solving the Problems) The present invention provides a double-tube type bulb in which an optical film made of a metal oxide is formed on at least one of the outer surface of the inner tube and the inner surface of the outer tube. By sealing the oxygen emitter, it is no longer necessary to forcefully contain oxygen in the initial atmosphere of the outer tube, and the necessary oxygen is generated inside the outer tube after sealing, and furthermore, the natural depletion of oxygen in the outer tube during lighting is eliminated. can be replenished.

(Function) If an oxygen releaser is sealed inside the outer tube, the necessary oxygen can be released after sealing by filling the outer tube with an inert gas that does not contain any oxygen or by making the outer tube a complete vacuum. If, exhaust m/
There is no need to fill the atmosphere gas containing oxygen in c. In addition, if oxygen is released little by little into the outer tube atmosphere while the light is on, natural depletion can be replenished.
There is no need to seal in excess oxygen during sealing, and the required amount of oxygen in the outer tube atmosphere can be maintained for a long period of time.

(Example) Hereinafter, details of the present invention will be explained with reference to illustrated embodiments.

FIG. 1 shows an example of a sealed beam type double tube halogen light bulb to which the present invention is applied. In the figure, (1) is a sealed beam outer tube, (2) is a halogen bulb inner tube sealed within this outer tube (1), and (3) is an optical film formed on the outer surface of this inner tube (2). (4) is an oxygen emitter sealed in the outer tube (1), and (5) is attached to the end of the outer tube (1). This is the amount that was paid.

The outer bulb (1) is a hard glass PAR3g sealed beam bulb (11), and a reflective film (12) made of aluminum or the like (indicated by a dashed line) is formed on the inner surface of a reflecting mirror (13a), and the front surface is It is closed with a lens (13b) and bonded with an adhesive (14) such as an epoxy resin, or it is welded with glass. The halogen bulb inner tube (2) is sealed inside the bulb (11) by means described later.

In addition, in order to form the bulb (11) of the outer tube (1) in the above, the opening portions of the reflecting mirror (13a) portion and the lens (13b) portion on which the aluminum reflective film (12) is formed are melted. In the case of this joining method, glass processing is performed through preheating and slow cooling steps not only at the time of joining, but also before and after the joining.

These operations involve high processing temperatures because the glass is hard, and the reflection [ll (12) of aluminum formed on the inner surface of the part (13a)] oxidizes and becomes self-destructive, lowering its reflectance and causing a decrease in the efficiency of the light bulb. Sometimes, this reflective film (
I2) Zinc oxide (ZnO) and silicon oxide (Sin2)
) can be used as a reflective film (
Oxidation and self-destruction can be prevented without reducing the reflectance of I2).

As shown in an enlarged view in FIG. 2, the halogen bulb inner tube (2) is made by crushing and sealing the end of a cylindrical (T-shaped) bulb (21) made of heat-resistant glass such as quartz glass. (22)
A pair of molybdenum introduced foils (23), (23), which are an example of introduction conductors, are buried in this sealing part (22), and l connected to these introduced foils (23), (23). A pair of inner conductors (24) and (24) are introduced into both ends of the bulb (21), and a tungsten coil filament (25) is installed between them and positioned at the center line of the bulb (21). The middle part is supported by an anchor (26), and a pair of outer conductors (27), (27) connected to the molybdenum introduced foils (23), (23) are connected to the sealing part (2).
2) Derived from the end face. Then, the valve (21)
The above-described visible light transmitting and infrared reflecting film (3) is formed on the outer surface, and the required halogen is sealed in the bulb (21) together with an inert gas such as argon. Then, the outer conductors (27) and (27) are connected to the outer tube (1) described above.
) are connected to support wires (15) and (1-5) brazed to ferrules (not shown) for electrical connection and mechanical support. By the way, the rating of this halogen bulb inner tube (2) is 110V851i1.

The visible light transmitting infrared reflecting film (3) is made of metal oxides such as titanium oxide (TiO2), tantalum oxide (TaO□), and zirconium oxide (ZrOz), as shown schematically and enlarged in Fig. 3. High refractive index layer (3H) (slanted line downward to the right), silica (SiO□), selenium oxide (SeO□)
A total of 8 layers of low refractive index layers (3L) (diagonal lines on the upper right) made of metal oxides are alternately layered, and visible light is transmitted through light interference and infrared rays are reflected.

The oxygen releasing body (4) is a gas-adsorbing silica sintered body, and has a particle size distribution as shown in, for example, FIG. 4 (based on a standard sieve).
It is obtained by molding precipitated silica powder into a rectangular rod shape and then sintering it at 300°C for 5 minutes.
The weight per piece is calculated and determined as described below. In the first place, in gas adsorbents, there is generally a difference between the adsorbed gas concentration (the amount of adsorbed gas per 1 g of adsorbent) and the gas concentration in the atmosphere (partial pressure or absolute amount in the atmosphere IQ). There is an equilibrium relationship depending on . If the adsorbed gas concentration is in excess of the equilibrium state between the temperature and atmospheric concentration at that time, this excess is rapidly released and the system becomes stable when a new equilibrium relationship is established. Furthermore, if the concentration of the gas in the atmosphere decreases for some reason when it is in an equilibrium state, the equilibrium relationship will be broken and a portion of the excess gas will be released from the gas adsorbent and the concentration in the atmosphere will decrease. increases, and a new equilibrium relationship is established.

When the temperature is low, an equilibrium relationship is established where the adsorbed gas concentration is high, and as the temperature increases, the equilibrium relationship shifts toward a lower adsorbed gas concentration.

The oxygen releasing body (4) made of the gas-adsorbing sintered silica has the same properties as the general gas adsorbing body described above, and also has a particularly high oxygen adsorption ability, and furthermore, the oxygen releasing body (4) made of the gas-adsorbing sintered silica Performance will not deteriorate.

The feature of this embodiment is that the outer tube (1
) is filled with an inert gas consisting of 90% argon and 10% nitrogen by volume.
Heat from the inner tube (2) releases oxygen from the oxygen emitter (4), making it weakly oxidizing. By the way, to give an example of the atmosphere inside the outer tube (1) after oxygen is released, the oxygen partial pressure is 0 for the above-mentioned inert mixed gas of 450 to 650 Torr.
．． 04~3.3Torr (10 (1~5000PPM)
is preferred. During long-term lighting, oxygen is gradually released from the oxygen release body (4) as the oxygen in the surrounding atmosphere inside the outer tube (1) is gradually depleted, and the above-mentioned oxygen partial pressure is required until the end of the life. The amount is maintained.

For this reason, the oxygen releaser (4) should be one whose adsorption properties are known in advance, and the oxygen releaser (4) should be used so that it can release the necessary oxygen at the first lighting and maintain the required residual adsorption amount. The appropriate amount of the support wire (15) is determined as described above, and the support wire (15) is used as the part that maintains an appropriate temperature during lighting.
It is attached to.

Next, the operation of the halogen light bulb of this embodiment will be explained. When this halogen bulb is installed in a socket and energized, the filament (25) of the halogen bulb inner tube (2) is heated to a high temperature and emits visible light along with a large amount of infrared rays, and these lights illuminate the bulb (21). The visible light passes through and enters the visible light transmitting infrared reflective film (3), and the visible light passes through this film (3) and is reflected by the aluminum reflective film (12) of the outer tube (1) to the front from the lens (13b). The infrared rays are reflected by this visible light transmitting infrared reflecting film (3) and are reflected by the filament (
25) and heats it. As a result, the luminous efficiency is significantly improved, and visible light with little infrared radiation, so-called cold light, can be emitted.

In such a lighting state, the bulb (21) and the sealing part (22) of the halogen bulb inner tube (2) are heated to a high temperature due to the heat generated from the filament (25).
Moreover, this inner tube (2) is sealed inside the outer tube (1), and the inside of the outer tube (1) is filled with a mixed rare gas with poor heat conduction, so cooling is poor. (21)
The temperature of the sealing portion (22) rises to nearly 800° C., and the temperature of the sealing portion (22) also rises to a temperature close to this. While holding the outer tube (1)
When the interior is first turned on, there is a weakly oxidizing inert gas atmosphere containing oxygen released from the oxygen emitter (4), so the metal oxides that make up the visible light transmitting infrared reflective film (3) decompose. The oxygen pressure and atmospheric oxygen pressure are almost balanced, and these metal oxides do not oxidize or reduce even though they are heated at high temperatures for long periods of time. Furthermore, as the lighting time becomes longer, oxygen in the atmosphere inside the outer bulb (1) is gradually lost, but it is gradually released from the oxygen release body (4) and replenished, so the minimum amount of oxygen is required until the end of the life. The concentration is maintained and the degree of oxidation of the metal oxide is maintained at the original oxide composition, eg, Tie, .5in2.

In addition, since the oxidizing property inside the outer tube (1) is maintained appropriately low, this atmospheric gas enters along the outer conductors (27) and (27) and introduces high-temperature molybdenum fi (23).
, (23) Even if it comes into contact with the molybdenum-introduced foil (23)
, (23) is hardly oxidized and the airtightness is not impaired even after long-term lighting.

Furthermore, in the halogen bulb of this embodiment, the atmosphere gas initially filled in the outer bulb (1) may be the above-mentioned argon-nitrogen mixed gas, so there is no harm even if a small amount of air or nitrogen in units of ppm gets mixed in during filling. On the other hand, if a halogen bulb of another tube type is filled with atmospheric gas immediately after the halogen bulb of this embodiment is filled with atmospheric gas, even if a trace amount of argon/nitrogen mixed gas in units of PPM is mixed into the halogen bulb. No harm. Furthermore, when multiple types of halogen bulbs with different oxygen contents are continuously evacuated and filled with atmospheric gas while the outer bulb (1) inner ambient gas is turned on, all halogen bulbs must contain the same component. Since it is only necessary to fill in the mixed gas, there is no need to vacuum clean the air supply system for a long time, improving productivity.

In addition, although the above-mentioned embodiment explained a sealed beam type halogen light bulb, the present invention is not limited to this, and the halogen light bulb inner bulb may be housed in a tubular or spherical outer bulb.
Furthermore, the light bulb is not limited to a halogen light bulb, and may be any other light bulb. Furthermore, the present invention is applicable not only to light bulbs but also to other bulbs such as high-pressure metal vapor discharge lamps. In short, the present invention
In cases where the inner tube is sealed within the outer tube and a visible light transmitting infrared reflective film is formed on either the outer surface of the inner tube or the inner surface of the outer tube or both, and the inner surface of the outer tube becomes hot during lighting, as described above, If the oxygen emitting body is sealed, even if the atmosphere inside the outer tube is an oxygen-free inert gas or vacuum at the time of manufacture, a suitable low concentration of oxygen can be released after sealing. It is possible to simultaneously prevent the deoxidation of the foil and the oxidation of the introduced foil. Furthermore, in the present invention, the metal oxide film is not limited to a visible light transmitting infrared reflective film, but may also be a visible light reflective infrared transmitting film or an anti-glare film, as long as it is an optical film made of a metal oxide.

Further, the oxygen emitting body is not limited to the above-mentioned gas-adsorbing sintered silica, but may be other gas-adsorbing bodies such as silica gel. Furthermore, the oxygen releaser may be various peroxides, etc.
Alternatively, oxygen gas may be sealed in a glass capsule, and other means such as laser light irradiation may be used to release oxygen from these oxygen emitters. You may replenish the necessary oxygen by heating repeatedly in small portions.

〔Effect of the invention〕

As described above, the present invention provides a device in which an inner tube containing a light emitting section is hermetically sealed within a glass outer tube through a gap, and an optical film made of a metal oxide is formed on at least one of the outer surface of the inner tube and the inner surface of the outer tube. In this method, since the oxygen emitter was sealed inside the outer tube, the inside of the outer tube was made into an oxygen-free inert gas atmosphere or a vacuum atmosphere at the time of manufacture, and an appropriate amount of oxygen was released from the oxygen emitter by the initial lighting or other means. Oxygen can be released to make the atmosphere inside the outer tube weakly oxidizing, improving the productivity of sealing the atmosphere inside the outer tube.Furthermore, if necessary, additional oxygen can be released appropriately during the life of the outer tube to make the atmosphere inside the outer tube weakly oxidizing. Since the natural depletion of oxygen can be replenished, deoxidation of the metal oxide constituting the optical film and oxidation of the introduced conductor can be simultaneously prevented until the end of the life.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway side view showing the inside of an embodiment of the halogen bulb of the present invention, Fig. 2 is an enlarged sectional view of the inner tube of the halogen bulb, which is the main part, and Fig. 3 is also a visible light bulb. FIG. 4, which is a schematic enlarged cross-sectional view of a transmitting infrared reflective film, is a graph showing the particle size distribution of raw material powder for producing an example of an oxygen emitter. (1)...Outer tube, (1]>...Valve, (12)...
- Reflective film, (13a)...Reflector, (13b)...
Lens, (2)...inner tube, (21)...bulb,
(22)...Sealing part, (23)...Molybdenum introduction foil which is an example of an introduced conductor, (25)...Filament which is an example of a light emitting part, (3)...An example of an optical film Visible light transmitting infrared reflective film, (3H)...high refractive index layer, (
3L)...Low refractive index layer.

Claims (1)

[Claims] An inner tube having a built-in light emitting part is hermetically sealed inside a glass outer tube through a gap, and an optical film made of a metal oxide is formed on at least one of the outer surface of the inner tube and the inner surface of the outer tube, wherein A tube characterized in that an oxygen emitting body is sealed in the tube.