JPS58204469A - Tungsten halogen lamp with metal additive - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to incandescent lamps, and more particularly to tungsten-halogen incandescent lamps. More particularly, the present invention has means incorporated to prevent filament sagging.

Therefore, we turn to tungsten-halogen type lamps which have a long life and can be operated in both vertical and horizontal modes.

Currently, the majority of incandescent lamps use tungsten wire or filaments of single-coil or dual-coil designs. When first energized to the incandescent state,
The filament recrystallizes metallurgically and sag into a physical circle under the action of gravity.

Double-coil filaments sag more than single-coil filaments, and thicker wires sag more than thicker wires.

In the vertical position, the sag - the top turn opens and the bottom turn collapses, acting as a collapse of the turn, or in the horizontal position, the sag depends on the dispersion of the filament support wire. Identified by the formation of catenary lines over it.

Initial tungsten filament (required during manufacturing)
The sagging could never be completely removed. However, this sagging can be greatly reduced by using a controlled heating process during initial lighting. Two different processes for doing this are in commercial use today, and these processes are briefly described below.

1. Pre-stabilization is the process mainly used for double coil filaments of halogen lamps. This involves raising the coil to a temperature of over 2400°C in the air prior to removing the mandrel for the primary coil, and also raising the temperature of the coil to over 2400°C in the air before removing the mandrel and attaching the threaded rod to 1eK.
During the formation stage of the secondary coil with attached coil, this
This includes raising the temperature to 00°C or higher. The result is a fragile coil that requires manual installation. This, along with the pre-stabilization process, results in a very expensive coil. However, the initial sag when the coil is first turned on is minimal.

2 Another way to stabilize the filament is to flash it. This is done after the coil is installed in the lamp, but may be done before or after tip-off.

The filament inserted into the receiver is not easy to break, so
It does not require manual installation and can therefore be installed inexpensively using self-made equipment. The first turn on under these conditions will have a larger initial sag than with a pre-stabilized coil.

Unfortunately, even though incandescent rank filaments have been pre-stabilized or flashed,
Continues to sag during subsequent lamp operations.

This is generally attributed to slippage at grain boundaries. It is known that this condition is exacerbated by the presence of gaseous oxygen. This causes large sag in halogen lamps. This is because a halogen write/write cycle has a higher proportion of oxygen in the gaseous state than in a non-halogen incandescent lamp. Generally, sag in non-halogen incandescent lamps is not severe because most of the residual oxygen is bound up at the tube wall as tungsten oxide, a colorless solid condensate. Therefore, there is not enough oxygen in the gaseous state to promote sagging.

However, in the case of halogen lamps, this secondary sag becomes a serious problem. This is because the oxides present are reduced by the halogen additive (HBr in this case) which promotes the presence of free oxygen in the gaseous state.

As with initial sag, fine filaments in two-coil form are particularly susceptible to severe secondary sag in a heliogen atmosphere. Additionally, chemical corrosion of the wire in the colder portions of the filament causes it to become thinner, resulting in premature arc-shaped sagging, which significantly shortens the service life.

This is more noticeable in thin mounds than in thick ones.

These curve fronts are even worse in low wattage, line voltage, tungsten-7 halogen lamps employing two-layer coil filaments. An example of such a two-wheel coil is one rated for 100 watts and 120 volts.

Such a coil is made of thin tungsten wire ([100
Formed from 125 mm/20 (1 tm) with a diameter of 25 inches, sagging and short life of the filament due to the presence of particles is a serious problem.

The use of halogens in incandescent lamps generally allows for significantly smaller vessel sizes than those required by non-halogen lamps of the same wattage.

In particular, the above-mentioned 100 watt filament is sealed in an A19 glass tube if it is non-halogen, and is sealed in a T5 glass container if it is attached with a halogen. The volumes of these two tubes are similar.

t A19=150cc ”l□2, T
Using a very small TSi device of 5 = 5.2C provides higher optical lateral pressure and thus increases lamp performance. However, the filament is much closer to the tube wall in the case of a T5 responder, and sagging of the filament during lighting in other than vertical positions brings the coil even closer to the tube wall. As a result, the local tube wall temperature increases, correspondingly increasing glass gassing and degrading lamp performance. In the most severe cases, the filament may sag to the point of contact with the tube wall.

As a result, the heat can cause the lamp to crack or melt, shortening the life of the lamp.

There are a number of techniques currently in use to resolve the problem of filament sag in this type of halogen lamp. However, all of these techniques have drawbacks that introduce new problems that force compromises in lamp performance. Some of the widely used techniques will be briefly explained.

1. Center support “1. Since we use a third machine that forms a loop around the center of the coil and is electrically isolated from the two end leads, the reduction in sagging is quite automatic. Sag in any other position than the vertical position will result in two sag m + less than the displacement of a single catenary line when the displacement from the original centerline is unsupported. However, the contact between the coil and the support edge creates a local cold spot, which becomes the center of increased halogen activity, with associated tungsten erosion. The thinning ultimately results in premature mounding.The center support a also makes the lamp difficult and expensive to manufacture.

λ Pre-Stabilized Coils As mentioned above, this process reduces overall sag, but the coils are fragile and require dry installation. This limitation results in considerable manufacturing costs that are unacceptable for, for example, the production of low 11 flT common lamps in conjunction with general purpose lighting.

6 Ignition with methane This is a well-known process used during Lang's co-location cycle, in which the filament is ignited with nitrogen and methane (CH
4) is energized in the atmosphere. The literature states that this reduces coil sag and attributes this benefit to the reaction of the tungsten filament with carbon in methane. However, one such as the lamp mentioned above
Tests with a 00 watt, 120 volt fill showed no reduction in coil sag compared to a lamp that was not lit in methane.

4. Other halides often used are hydrogen bromide (HBr).
). This hydrogen bromide is highly corrosive and is therefore considered less desirable than carbon-containing halides by some lamp manufacturers.

Tests have shown that there is no advantage to using this type of halogenation (v!+C)i2Br2). However, there are serious drawbacks when using this gas. It means that the light output decreases considerably, which means that CH! This is caused by a layer of carbon deposited on the inner tube wall during initial lighting when Br2 is decomposed into elemental states.

V. Reducing the content of halogen Tests have shown that reducing the content of halogen in the fill gas significantly reduces filament sagging and corrosion. Unfortunately, this also increases the percentage of lamps that darken too quickly due to imperfections in the halogen regeneration cycle.

Lamp blackening of the halogen rung is a lamp defect, even if the filament lights up and works. Reputable lamp manufacturers will not tolerate such conditions.

& Capacitor = Turtle Flashing This is a process that attempts to achieve the results exhibited by pre-stabilized filaments while avoiding the problems of fragile coils and hand installation. This includes stabilizing the filament after installation, exhaust cycle, or tip-off. A capacitor is used to generate some energy pulses through the coil. The pulse duration is very short compared to the normal series-ballast flash process used by many lamp manufacturers. This short duration greatly reduces the heat dissipation effect on the metallurgy of the coil due to the lead-in clamp. The fill therefore becomes more fully stabilized in the clamp area where sag problems occur. However, this method is believed to achieve, at most, only a portion of the desired effect and to increase the cost.

l Coil design with minimal sag The coil design exhibiting minimal sag is the most severe T,
P.I. and the lowest mandrel-to-wire (coil) ratio.

However, all of this is due to the #'
Must be performed within the l-valley limits. Similar to the flash with a capacitor of 2, it is believed that a coil design with no sag will achieve only a fraction of the desired effect.

Therefore, the object of the invention is to eliminate the above-mentioned drawbacks of the prior art.

Another object of the invention is to improve tungsten-halogen lamps.

Another object of the invention is to greatly reduce the sag of the primary and secondary filaments in incandescent lamps.

Another aspect of the present invention is BSJ to reduce halogen-induced filament corrosion of tungsten-halogen filaments.

These objectives, in one aspect of the present invention, include an effective amount of copper within the PiI group environment of the filament to substantially eliminate sag in the primary and secondary filaments;
This is accomplished by providing a lamp that has greatly reduced halogen-induced filament corrosion in lamps containing a halogen light fill. Allows for the installation of halogen lamps with a high wattage and low power consumption. These rungs are characterized by the superior lumen retention (percentage of light output retained from the original light output as the lamp is used) associated with lamps that use halogen regeneration cycles. Excellent life ratings are also obtained whether the lamp is operated with the filament vertically or horizontally.

In order to fully understand the present invention, preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring in detail to the accompanying drawings, there is shown a tungsten-halogen lamp 10 having a light-transmissive, hermetically sealed glass envelope 12. Container 12 can be fabricated from a tube of quartz or hard glass, such as Corning 1720 alumina silicate glass.

In a preferred embodiment, container 12 carries T S (
It is constructed with an outside diameter α of 625 inches, a wall thickness of [1040 inches], and an overall length of about 1675 inches.

The long lead-in wire 14 and the short lead-in wire 16 are connected to the pressure sealing part 1.
8 and extends into the container 12 . preferably in the form of a two-wheel coil, and e.g. 120 volts,
A 100 watt rated tungsten filament 20 is clamped between the inner ends of the lead-in wire and extends along the longitudinal axis 22 of the container 12. Evacuation and filling ports 24 are provided as usual. After evacuation, the lamp 10 is filled with an excess of halogen-containing vapor, ie, light-filling gas. In the preferred embodiment, the fill gas is 1%.
Tagata, i.e., about 1 to 10 ki, by volume percent 88% krypton, 1179% nitrogen, and 0
．． Consists of 21% hydrogen bromide (HBr). The preferred original lateral pressure is 5 atmospheres absolute. Container 12 also contains an amount of copper, for example in small nodules that are noticeable within the container.

It has been found that including copper in the lamp reduces filament sag and filament corrosion.

this? The life test conducted on kht at 120 volts without adding any copper gave a normal result.

t Lit in vertical position 2500 hours h (average) - holder is inserted life 2, lit in horizontal position 1000 hours (maximum) - holder not inserted life Defects in lighting in vertical position are normal filament defects It was characterized by a clean lamp with (broken wire). Illumination defects in the horizontal position were characterized by sagging or prematurely arcing coils and clean lamps due to corrosion thinning of the tungsten wire to the bulb wall.

The results of the life test when copper was contained in the lamp vessel were as follows.

t 2,500 hours of lighting in vertical position (average) - life of 2.7 hours of lighting in vertical position (average) - life of 2,500 hours of lighting in horizontal position - life of 2500 hours (average) in vertical position - life of 2500 hours in vertical position - all defects when containing copper are normal filament It was especially lit by a clean lamp with defects.

A micro-inspection of both samples with and without spurious additives was conducted during the life test program.

Sunfour without 1 #A showed a gradual accumulation of tungsten simulite-like deposits on the 1eK coil near the clamp by the lead wire. This is a clear indication of high levels of halogen activity that could reduce filament life.

2. Samples of lamps containing steel did not exhibit simulite-like growth at any time during their lifetime. however,
It seems to be completely new for halogen lungs @1. I saw a festival. The introduction of copper or molybdenum gradually accumulated as a film on the glass, but not on the inner surface of the glass.

This is indicative of a successful copper-halogen cycle that does not impose a shadow field on the regeneration cycle, as evidenced by the absence of blackening of the tube during its life. The second phenomenon observed was the blackening of the strawberry leaves of the original phlegm.

A considerable reason for this blackening is the reaction with residual oxygen in the gaseous state characteristic of all halogen lamps.

Thus, copper appears to act as an oxygen getter with dual results.

1. Removal of oxygen reduces the concentration of gaseous oxygen, which is the cause of the known sagging in tungsten filaments. This is true for both the norogen and non-orogen formats.

2. Removing oxygen from the gaseous state reduces halogen activity, which is known to be increased by additional blood gaseous oxygen.

In summary, therefore, it can be said that adding copper to halogen lamps with very fine wire filaments can eliminate premature coil defects caused by sagging and/or by halogen erosion.

Although what is presently considered to be the preferred embodiment of the invention has been illustrated and described, various modifications and changes may be made without departing from the scope of the invention as defined by the claims. This should be obvious to engineers in this field.

4. The attached opening of the first page is a schematic cross-sectional view of a lamp embodying the invention.

10: Tungsten-halogen lamp 12 glass containers 14: Long lead-in line 16: Short lead-in line 18: Pressure vs. top 20: Tungsten filament 24: Exhaust and light port Agent's name: Motohiro Kurauchi 1 fart\

Claims (1)

[Scope of Claims] (1) an optically transparent, hermetically sealed glass container having a longitudinal axis; two lead-in wires sealed in the container; and attached to the lead-in wires; and a tungsten filament extending substantially along said longitudinal direction #I, a fill gas in said container containing a halogen, and a quantity of steel and metal fittings contained within said cutting container; An incandescent rank characterized in that the pole rat is effective in substantially eliminating slack in the filament regardless of the physical arrangement of the lamp in use. (2) Rank-0 according to the unclaimed item 1 having a volume of 1 K'8 or less or less than about 6 CC; (3) The filling gas is about 88% krypton, 11
．． 79% of nitrogen and 0.21% of hydrogen bromide in amounts of krypton, nitrogen and hydrogen bromide - Lamp according to paragraph 1. 4. The lamp of claim ib, wherein said lead-in wire is made of an alloy of molybdenum containing about 3% tantalum. (5) The lamp according to claim 1, wherein the filament is a two-wheeled coil. (6) The lamp according to claim 1, wherein the glass container is single-ended and made of alumina-silicate glass. The lamp according to item 5. (7) The filling pressure of the filling gas is f at room temperature.
The lamp according to claim 6 in the scope of the patent M, which is between Jl and 10 atmospheric pressures absolute. (8) The lateral pressure of the filling gas is vortex 5 at room temperature.
7. The lamp according to claim 6, which is an absolute atmospheric pressure.