JPS59184448A - High pressure electric-discharge lamp - Google Patents

Abstract

PURPOSE:To provide a high pressure electric-discharge lamp which can be easily restarted by specifying the distance between an electrode coil wound around a main electrode and the fusing area of an emission tube. CONSTITUTION:An electrode coil 34 is coated with an electron-discharging matter. An electrode core wire 31 is fused to the end of an emission tube 1. When power supply voltage is applied after the lamp is turned off, a glow starter 15 operates and a heating body 14 is heated releasing electrons. At this point, according to the operation of the glow starter 15, surge voltage is applied to main electrodes 2a and 2b. The electrons released from the heating body 14, after inducing local dielectric breakdown between the heating body 14 and a starting auxiliary body 2a, travel along the inner surface of an emission tube 1 and at last reach the electrode coil 34 after passing through the core wire 31 of the main electrode 2b, thereby producing a spot of electric discharge. If the distance (L) between the fused end (A) and the end of the electrode coil 34 is too large, repeated operation of the glow starter 15 becomes inevitable and the restarting time increases. Therefore, it is desirable in terms of the practical use of the lamp that L/I be not larger than 2. In addition, it is proper that the lowest limit of L/I be 0.1 because the temperature of the wall of the emission tube 1 is too much increased by the electrode coil 34 if L/I is too small.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high pressure discharge lamp, and particularly to a high pressure discharge lamp with improved restart characteristics.

Conventionally, high pressure discharge lamps have been used on roads, sports grounds, gymnasiums, factories, etc.
Because it is compact and highly efficient, it has attracted attention as a power-saving light source, and its use has gradually spread to commercial facilities. However, high-pressure discharge lamps have the disadvantage of long restart times.

This high-pressure discharge lamp will be explained using a high-pressure mercury lamp (hereinafter referred to as a mercury lamp) as an example. FIG. 1 is a perspective view of the inside of a bulb showing the structure of a high-pressure mercury lamp.

(1) is an arc tube made of quartz glass, (2a), (
2b) A pair of Fi main electrodes, (3) Fi main electrodes (2a), (
2b) is an auxiliary electrode provided near the electrode. Luminous tube (1
1 is filled with mercury and argon gas.

(4a) and (4b) are molybdenum foils, (5a) and (5
b)' is linide, (b) is stem, (7a), (7b)
is stem lead, (8) is base, (9) is support frame, shout is molybdenum foil, Q') is lead, @ is resistor, 03
is the outer tube.

The main electrode (2a) is connected to a stem 1 fixed to the stem (b) via a molybdenum foil (4a) and a lead (5a).
(7a), the main electrode (2b) is connected to the molybdenum W3 (4b), the lead (5b) and the support frame (
9) to the stem lead (7b), and the stem leads (7a) and (7b) are connected to the base (8). The auxiliary electrode (3) is made of molybdenum Wif101,
The support frame (9) is connected via the lead (111) and the resistor (6).
). The outer tube 03 is an outer shell of a tube that collects sound from each of the above-mentioned members. Its inner surface is coated with a phosphor, and its interior is filled with nitrogen.

In the above-mentioned high-pressure mercury lamp, when voltage is applied via the ballast, first the auxiliary electrode (3) and the main electrode (2a)
A discharge occurs between the electrodes (2 and 2), and this auxiliary discharge causes the electrode (2
A discharge occurs between a) and (2b), and the lamp lights up.

However, in this high-pressure mercury lamp, the mercury vapor pressure inside the arc tube (2) reaches several atmospheres while the lamp is on, so if the lamp stops discharging due to a temporary drop in the power supply voltage, the power supply voltage will return to normal. Even if the value returns to -, the lamp cannot be started immediately, and the temperature of the arc tube (1) decreases.
The pressure of mercury vapor in the arc tube (1) reaches a point where discharge can start.
It was impossible to turn on the light until the condition deteriorated. In this way, the time from when the lamp goes out until it can start discharging again is:
This is called the restart time, and for high-quality mercury lamps, a time of 3 to 5 minutes was required.

Therefore, in order to shorten this restart time, a heating element is installed near the main electrode, and when restarting, this heating element is heated to release electrons into the discharge space, and a voltage is applied between the main electrodes. The method is known to be effective.

However, if a starting aid is installed outside the arc tube where the heating element is left, the distance from the electrode coil wound around the main electrode to the arc tube sealing part is important in order to quickly light up the discharge lamp. The inventors have found that.

That is, this invention includes an arc tube having a heating body, a starting aid on the outside of the arc tube, and a part where the core wire is fixed to the light emitting sealing part from the end of the electrode coil wound around the core wire of the main electrode. The purpose of this invention is to provide a high-pressure discharge lamp that is easy to restart by setting the distance from the lamp to 0.1 (L/I < 2) with respect to the discharge lamp's rated current (ampere). It is something.

FIG. 2 is a perspective view of a tube showing a specific configuration of a high-pressure mercury lamp according to an embodiment of the present invention.

In the figure, (1) to (9) have the same reference numerals as in Figure 1.
(14) is a heating element provided near the main electrode (2a), (15) is a lighting tube, (16) is a ballast, (20) and (21) are terminals, ( 22nd, (23)
, (24) are all leads, (25) is molybdenum foil,
(26), (27), and (28) are leads, and (29) is a starting auxiliary body, which is a winding made of molybdenum wire of O11mIφ on the outer surface of the arc tube (1). Further, both ends thereof are connected to a support frame (9).

Main electrodes (2a) and (2b) are provided at both ends of the arc tube (1), and a heating element (14) is provided near the main electrode (2a).

The main electrode (2a) is made of molybdenum foil (438 leads (5
a) Stem lead (7a), lead (22), stabilizer (
16) and the base (8) via the lead (23), and the other main electrode (2b) is connected to the molybdenum foil (4b
), lead (5b), support frame (9), stem lead (7
b) and the lead (24). One terminal of the heating element (14) is welded to the molybdenum foil (4a), and the other terminal is welded to the molybdenum foil (25). ), the lead (26), and the stem lead (7C) and (27) are connected to the terminal (20) of the lighting tube (15), and the terminal (21) of the lighting tube (15) is connected to the lead (28).
) is connected to the stem lead (7b). A molybdenum wire starting aid (29) wrapped around the outer surface of the arc tube (11) has the effect of lowering the starting voltage. The fluorescent tube (1) is coated with a phosphor and nitrogen gas is sealed inside.The arc tube (1) has an inner diameter of 6 mm, a distance between the main electrodes (2a) and (2b) of 1611 m, and an internal volume of , 9.57cc, and mercury and argon gas are sealed inside. Each stem lead (7a), (7b), (7C) is hermetically inserted into the outer tube (13), and the lighting tube ( 15) and ballast (16
) etc. are housed in a case (30) that is integrally provided between the outer tube (13) and the cap (8).

In the above-mentioned high-pressure mercury lamp, when the power source (17) is directly connected to the base (8), the lighting tube (15) is first activated, current flows through the heating element (14), and the heating element (14) Electrons are emitted from the At this time, a surge voltage is generated in the ballast (16), and as a result, electrons emitted from the heating body (14) are accelerated toward the main electrode (2b), so the main electrodes (2a), (2b ) increases, a discharge starts, and the light is turned on. The discharge starting voltage at the time of restarting the conventional high-pressure mercury lamp was 4 kV1, but the discharge starting voltage of the high-pressure wood-like lamp of this embodiment was reduced to about 1.5 kV.

The inventors conducted various studies on restarting this high-pressure mercury rung [7] and found that the distance from the light-emitting sealed end of the core wire of the main electrode sealed at the end of the light tube to the electrode coil was We found that there is a relationship between speed and speed. This will be explained in detail below.

Figure 3 shows that the main electrode (2b) according to the present invention is connected to the arc tube (1).
).

Overall, it is a local cross-sectional view, but the part surrounded by the wavy line (
Please take a look at B) with the understanding that it is part of the exterior drawing. In the figure, (31) is the electrode core wire, and (32) is -
The secondary coil (33) is a secondary coil, and (34) is an electrode coil. An electrode coil (34) is wound around the tungsten electrode core wire (31), and the electrode coil (34) includes a part of the coil (32) and a secondary coil (
33). The electrode coil (34) is coated with a mixture of electric BeO. The electrode core wire (31) is sealed at the end of the arc tube (1). This sealed end (
The distance L (print) from 4) to the end of the electrode coil is related to the speed of lighting upon restart.

Figure 4 shows fried I7N with the above L(W) changed,
FIG. 3 is a characteristic diagram showing a relationship with restart time. In this case, ■ indicates the rated current of the lamp (4), and the restart time refers to the time when the lamp is turned off once and then immediately restarted.
This refers to the time it takes for the lamp to start discharging and turn on after power is applied. The reason why the distance is related to the restart time is as follows.

After the lamp is turned off, when a power supply voltage is applied, the lighting tube (15) operates, heating the heating element (14) and emitting electrons.

At this time, a surge voltage is applied to the main electrodes (&) and (2b) by the operation of the lighting tube (15). Heating body (1
The electrons emitted from 4) first cause local dielectric breakdown with the starting aid (2a), and this local breakdown develops one after another along the starting aid (29), and finally the main The electrode (26) is reached. Since this dielectric breakdown progresses along the inner surface of the arc tube, it eventually propagates through the main electrode (2bFl core wire (31), reaches the electrode coil (34), and produces a discharge spot. Therefore, as the above distance increases, , lighting tube (1
The operation 5) will be repeated, which will lengthen the restart time. From the figure, it is desirable that L/■ be 2 or less for practical purposes of the lamp. Also, if L/I becomes smaller, it is better from the point of view of restarting, but the electrode coil (34)
If the electrode coil (34) is too close to the wall of the arc tube, the temperature of the wall of the arc tube will rise too much during lamp operation due to the electrode coil (34). Accordingly, as seen from the figure, 0.1 is appropriate for the lower limit value of 'I.

In addition, although the above embodiment described a high-pressure wood-like lamp,
The present invention is also applicable to other high-pressure discharge lamps such as high-pressure sodium lamps and metalloide lamps. Distance L from the coil to the sealed end (rigidity is o, u (L/I < 2) relative to the current (ampere) makes it easier to cause discharge in the main electrode diagram and restart. There is an effect.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the internal structure of a conventional high-pressure mercury lamp, FIG. 2 is a perspective view showing the internal structure of a high-pressure mercury lamp according to an embodiment of the present invention, and FIG. FIG. 4 is a partially enlarged sectional view (including a partial external view) showing the structure of the end of the arc tube according to the embodiment of the present invention.
FIG. 7 is a characteristic diagram showing the relationship between restart time when the distance from the arc tube sealing end of the main electrode to the electrode coil is changed. In the figure, (1)... Arc tube, (2a included (';h)...
...Main electrode, (3) ...Auxiliary electrode, (4
1), (4b) --- Molybdenum foil, (5a)
,(5b)-,,. Lee-P, (61... Stem, (7a), (7b
)・・・Stem lead, (8)・・・−・Base,
(9)...Support frame, (10)...Molybdenum foil, (1)...Lead, (12>...
・Resistance, (13)...Outer tube, (14)...
・Heating body, (15)... Lighting tube, (16) 4... Ballast, (20), (21), (22), C23
), (24)...- Lead, (25) Four...
Molybdenum foil, (26), (27), (28)...
...Lead, (29) ...Starting aid, (30
G... Case, (31 units... Electrode core wire (32
)...-secondary coil, (33)...secondary coil, (34)...electrode coil. The symbols in the middle of each figure indicate the same or equivalent parts. Agent Masuo Oiwa (2 others) 7th floor / Fukushima

Claims (1)

[Scope of Claims] A pair of main electrodes are provided at the ends of the arc tube, a heating element is provided near one of the main electrodes, and a starting aid is provided outside the arc tube, and the main electrode is connected to the electrode center. It is composed of a wire and an electrode coil wound around the wire, and the distance from the point where the electrode core wire is fixed to the arc tube to the electrode coil is L < M
) to the discharge lamp current (ampere) K is 0.1 (I (2).