JPH0468760B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a lamp starter using a glow lamp used for starting a metal vapor discharge lamp.

Prior Art A conventional example of this type of lamp starter applied to a high-pressure sodium lamp will be explained.

Figure 1 is a circuit diagram of a general lamp that uses a glow lamp as a starter. 1 is an arc tube, and electrically in parallel with this arc tube 1 are a glow lamp 2, a bimetal switch 3, and a resistor. 4 series circuits are built into an outer tube 6 whose interior is evacuated. In the above circuit, the circuit portion consisting of the glow lamp 2, bimetallic switch 3, and resistor is generally referred to as a lamp starter S. To start a lamp having such a structure, first, when power is applied between A and A', the applied voltage is first applied to the electrode 2a of the glow lamp 2, and the glow lamp 2 starts glow discharge. This glow discharge deforms the electrode 2a in the glow lamp 2, causing the electrode 2a to become short-circuited and stop the glow discharge. Therefore, the electrode 2a separates again and at this moment a high voltage is generated across the choke 5, starting the arc tube 1. Luminous tube 1
Once started, the glow discharge will not occur again. If the arc tube 1 does not start, the electrode 2a in the glow lamp 2 will continue to be short-circuited due to self-heating, the resistor 4 will become red hot, the bimetal switch 3 will be heated, and the circuit 2-3-4 will be closed. Because of this, the electrode 2a in the glow lamp 2 is released from its short-circuited state and starts glow discharge, causing the arc tube 1 to start.
As the resistor 4, a filament-like material or a highly heat-resistant carbon film resistance element is used. However, in the circuit structure shown in FIG. 1, the structure for attaching the resistor 4 requires a mounting base 7 made of ceramic to bury the bimetal 3 and the resistor 4, as shown in FIG. This is uneconomical in terms of space and man-hours, and even when it is housed within the lamp outer tube 6, a large amount of space is required, resulting in a complicated mounting structure.

In order to improve the above-mentioned drawbacks, the following configuration has been proposed by the present applicant. This will be explained using FIG.

The difference between FIG. 3 and FIG. 1 is that the bimetal switch 8 uses a self-heating type bimetal. That is, the bimetal 8 is a bimetallic material with a high specific resistance, and when electricity is applied, the bimetal 8 itself is heated, and the bimetallic operation is started by the heat. Starting a lamp such as that shown in FIG. 3 is as follows. That is, first, when power is applied between A and A', a voltage is applied between the choke 5, the glow lamp 2, and the bimetal switch 8, and the glow lamp 2 starts glow discharge. Similar to the starting condition shown in FIG. 1, the glow lamp 2 is short-circuited, and the instant it is separated, a high voltage is generated and the arc tube 1 is started. If the arc tube 1 does not start, the glow lamp 2 may become short-circuited as shown in FIG. Perform the action, 2
-8 circuit is immediately disconnected.

At this time, the arc tube 1 starts due to the shearing effect. If the arc tube 1 does not start, the short-circuited state of the glow lamp 2 is released and glow discharge is started again, causing the arc tube 1 to start.

The structure of the prior application is superior in that it does not require a filament, carbon film resistor, etc. However, in the above proposed example, as a starter,
Because two components, the glow lamp 2 and the self-heating bimetallic switch 8, are required, it has sometimes been difficult to design a starter for extremely small metal vapor discharge lamps of about 30 to 50 W.

Summary of the Invention The present invention has been made in view of the above-mentioned problems.
To provide a glow lamp whose main part is "a glow lamp in which power is supplied to a pair of glow discharge electrodes having bimetallic electrodes", which has a simple structure and can be easily installed in a small metal vapor discharge lamp. The purpose is to

Embodiment of the Invention An embodiment of the invention will be explained based on FIGS. 4 and 5.

FIG. 4 is a diagram showing the configuration of a glow lamp as a starter according to the present invention. In the figure, 2' indicates the entire glow lamp as a starter, and inside the glass tube is an electrode rod 2b facing a bimetallic electrode 2a. There is also a rare gas such as Ar sealed in the glass tube. In these respects, it is no different from a normal glow lamp. The difference from a normal glow lamp is that there is a self-heating bimetallic electrode 2c in contact with the bimetallic electrode 2a. External input is from the electrode rod 2b and the self-heating rod-shaped bimetal electrode 2.
The bimetallic electrode 2a is connected to the input via a self-heating bimetallic electrode 2c.

The operation will be explained using FIG. First, A
When power is applied between -A', glow discharge is started between 2a and 2b of glow lamp 2'. At this time, electrodes 2a and 2c are in contact. When the bimetallic electrode 2a is heated by the glow discharge, the bimetallic electrode 2a is heated and deformed as in a normal glow lamp, short-circuiting with the electrode rod 2b, the glow discharge ends, and the cooled bimetallic electrode 2a is heated again.
At this moment when it separates from the electrode rod 2b, a pulse voltage is generated across both ends of the yoke 5, and the arc tube 1 starts to normally start due to this pulse voltage. Moshiro luminous tube 1
If the electrode 2a and the electrode rod 2b do not start, the short circuit between the electrode 2a and the electrode rod 2b may continue. In such a case, a current continues to flow between the electrode rod 2b, the electrode 2a, and the electrode 2c, and the self-heating bimetallic electrode 2c is heated, and the electrode 2c is separated from the electrode 2a by the heat. At the moment of separation, a pulse voltage is generated across the tube 5, starting the arc tube 1.

At this time, since no current flows between the electrode 2a and the electrode rod 2b, the heating of the bimetallic electrode 2a ends.
The short circuit between the electrode 2a and the electrode rod 2b is released, but when the arc tube 1 is started, the lamp voltage is applied between the electrode 2a and the electrode rod 2b, so the glow discharge between the electrode 2a and the electrode rod 2b is It doesn't happen.

If the arc tube 1 does not start, after the electrodes 2a and 2c come into contact, a glow discharge will occur between the electrodes 2a and the electrode rod 2b, and the arc tube 1 will start again. In this way, with the structure of the glow lamp of the present application, unlike conventional glow lamps, there is no need to worry about the short-circuit state continuing after glow discharge, and there is no need for parts such as filaments, so it is possible to use a glow lamp of 30 to 50W. It is particularly effective for small space-saving metal vapor discharge lamps such as low wattage metal vapor discharge lamps. Note that, as a matter of course, the self-heating bimetal 2c must be set so as to be separated from the electrode 2a after the short circuit between the electrode 2a and the electrode bar 2b begins, which prevents glow discharge between the electrode 2a and the electrode bar 2b. It should not work in heat. This can be solved by setting the position of the electrode 2c away from a place where glow discharge between the electrode 2a and the electrode rod 2b is likely to occur.

Further, as another embodiment, the one shown in FIG. 6 can be considered. That is, the electrode rod 2b is eliminated, and in its place a self-heating bimetal is used as an electrode opposite to the electrode 2a.

The operation of this glow lamp will be described based on FIG. First, when a glow discharge occurs at point a and a short circuit continues as shown at point b, the electrode 2c operates to break the short circuit. Even with this structure, the fifth
An effect similar to that shown in the figure is achieved.

Note that in the case of the configuration shown in FIG. 6, the self-heating bimetallic electrode 2c has a thermal behavior that causes the bimetallic electrode 2a to warp inward.
It is necessary to have opposite thermal behavior characteristics such as outward curvature.

In the above-described embodiments, a high-pressure sodium lamp was used as an example of the lamp, but it is possible to use other metal vapor discharge lamps such as metal halide lamps. Furthermore, in the description of the glow lamp, a glow lamp with Ar gas sealed therein was used, but it is of course possible to use other gases such as a mixed gas.

Effects of the Invention As described above, according to the present invention, there is no need for a filament or the like, and there is no need to have any other bimetal in addition to the glow lamp as in the proposed example, so the structure is simple and the low-wattage lamp takes up little space. It is extremely effective as a starter for metal vapor discharge lamps and provides a glow lamp.

[Brief explanation of drawings]

Figure 1 is a circuit diagram of a conventional high-pressure sodium lamp, Figure 2 is a perspective view of a conventional starter, and Figure 3 is a perspective view of a conventional starter.
The figure is a circuit configuration diagram of a lamp according to a proposed example, and FIG. 4 is a structural diagram of an embodiment of a glow lamp according to the present invention.
FIG. 5 is a circuit diagram of a lamp according to the present invention, and FIG.
The figure is a structural diagram of another embodiment of the glow lamp according to the present invention, and FIG. 7 is an explanatory diagram of the operation of the glow lamp shown in FIG. 6. In the figure, 2 is a glow lamp, 2a is a bimetallic electrode, 2b is an electrode rod, and 2c is a self-heating type thermally responsive element. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. A glow lamp in which power is supplied to a pair of glow discharge electrodes each having a bimetallic electrode via a self-heating bimetallic electrode, wherein the self-heating bimetallic electrode is normally connected to the bimetallic electrode. 1. A glow lamp characterized in that the lamp is arranged so as to be in contact with an electrode and to be separated from the bimetal electrode during predetermined self-heating. 2. A glow lamp configured to supply power to a pair of glow discharge electrodes having bimetallic electrodes via a self-heating bimetallic electrode, wherein the self-heating bimetallic electrode is connected to one of the pair of glow discharge electrodes. 1. A glow lamp characterized in that the electrode also serves as an electrode other than a bimetallic electrode, and is arranged so as to be separated from the bimetallic electrode during predetermined self-heating.