JPS5916389B2 - High pressure discharge lamp with built-in starting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high-pressure discharge lamp with a built-in starting device, particularly to a metal-ride discharge lamp and a high-pressure sodium lamp.

Recently, in order to improve the efficiency of high-pressure sodium lamps, high-pressure sodium lamps have been developed that use xenon gas as the starting rare gas sealed in the arc tube and have a higher filling pressure than conventional ones.

However, this high-pressure sodium lamp has a high starting voltage,
In order to light this with a mercury lamp ballast, a starting auxiliary circuit consisting of a series body of a bimetal switch and a resistor is connected in parallel with the arc tube and installed inside the outer bulb.

FIG. 1 shows a lighting circuit for a conventional high-pressure discharge lamp with a built-in starting device.A starting auxiliary conductor 4 is provided on the outer surface of this high-pressure discharge lamp and ζ discharge tube 1 via a first bimetal switch 2. Further, a series body of a second bimetal switch 3 and a resistor 5 is connected in parallel with the discharge tube 1, and these are housed in a common outer sphere 6.

Inductive ballast 7 for high pressure discharge lamps with such a configuration
When connected to the power source 8 via the ballast 7, current flows through the series body of the second bimetal switch 3 and the resistor 5, causing the resistor 5 to become red hot.

The second bimetal switch 3 is heated by the red heat of this resistor 5 and opens after a few seconds, but at that moment, the current flowing to the ballast 7 is suddenly cut off, so the ballast 7
A pulse voltage is induced.

With this pulse voltage, the starting assisting effect of the starting assisting conductor 4 provided on the outer surface of the discharge tube 1 is added, and the discharge of the discharge tube 1 is started.

However, in such a high-pressure discharge lamp with a built-in starting device, when the lamp is restarted, that is, when the power is cut off during lighting and then turned on again, the first bimetal switch 2 remains open and the second bimetal switch 2 is turned on. The second bimetal switch 3 returns to the closed state, and even if a pulse voltage is induced in the ballast 7 due to this closure, discharge does not start in the discharge tube 1, and the second bimetal switch 3 continues to open and close. A resistor 5 generally made of a tungsten filament,
There was a problem that the life of the ballast T was shortened.

Further, there was also the problem that the light emission and flashing of the resistor 50 was repeated for a long time, giving a feeling of discomfort.

The present invention has been made in view of these problems, and an object of the present invention is to provide a high-pressure discharge lamp with a built-in starting device that can operate reliably upon restart and prevent shortening of the life of the ballast and resistor. The purpose is to

To achieve this object, the present invention provides a first starting auxiliary circuit consisting of a discharge tube, a starting auxiliary conductor provided on the outer surface of the discharge tube, and a first bimetal switch connected in parallel with the discharge tube. and has a second starting auxiliary circuit made of a series body of a resistor and a second bimetal switch inside the outer sphere, and the return time of the first bimetal switch is the return time of the second bimetal switch. It features a high-pressure discharge lamp with a built-in starting device that is set to a shorter length.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a front view of essential parts showing an example of the starting device used in the high-pressure discharge lamp with built-in starting device of the present invention, and FIG. 3 is a side view of the same.
FIG. 4 is a side view of the main parts of a high-pressure discharge lamp in which this starting device is built into the outer bulb.

In the high-pressure discharge lamp with a built-in starter device of the present invention, the electrical connection between the discharge tube and the starter device is the same as that in FIG.

In addition, in FIGS. 2 to 4, parts common to those in FIG. 1 are given the same numbers.

In FIGS. 2 and 3, the resistor 5 is composed of a filament made of tungsten, and is wound and fixed around an insulator 9 made of a heat-resistant insulating material such as alumina.

This insulator 9 has a thickness of 2 to 3 u, a width of 15 to 20 M, and a length of 25 to 401 r IJ! It is an L-shaped rectangular plate, and a plurality of grooves 9a for holding the resistor 5 are provided at regular intervals on two opposing sides.

Furthermore, holes 9b and 9e for fixing the first and second bimetal switches 2 and 3, and a hole 9d for attaching to a support column described below.

9e is provided.

Further, a window 9f for transmitting light is provided in the central portion.

As mentioned above, the first and second bimetal switches 2
, 3 are both attached to the insulator 9 using holes 9b and 9c, but the second bimetal switch 3 is attached to the resistor 5.
On the other hand, the first bimetal switch 2 is arranged at a position slightly away from the insulator 9 so as not to face a part of the resistor 5.

As shown in FIG. 4, such a starting device is mounted on a support column 15, the first connecting terminal 12 is connected to the starting auxiliary conductor 4, and the second connecting terminal 13, 14 is connected between the power supply terminals. Connected.

As will be seen, the first bimetal switch 2 is located further away from the discharge tube 1 than the second bimetal switch 3.

According to such a configuration, the first bimetal switch 2
Since it is provided at a position farther from the resistor 5 than the second bimetal switch 3, it is less susceptible to the effects of radiant heat from the resistor 5.

This prevents the discharge tube 1 from opening before the discharge of the discharge tube 1 starts when the discharge lamp is started.

Since the first bimetallic switch 2 is also provided at a position farther away from the discharge tube 1, the temperature during operation of the discharge lamp is lower than that of the second bimetallic switch 3, so that the temperature at which the discharge lamp is restarted is lower. is the second bimetal switch 3
The closed state is always returned to the closed state first.

Therefore, the pulse voltage induced in the ballast by opening the second bimetallic switch 3 is always applied to the starting auxiliary conductor 4 via the first bimetallic switch 2, and the discharge tube 1 is reliably restarted. Become.

Furthermore, according to the configuration in which the first and q-second bimetal switches 2゜3 are provided at different positions from the discharge tube 1, there is no need to make the contact pressures of the two different, and no time is required to adjust the contact pressures. .

As explained above, the present invention can provide a high-pressure discharge lamp with a built-in starting device that can ensure reliable operation when restarting and can prevent shortening of the life of the resistor and ballast. be.

[Brief explanation of the drawing]

Figure 1 is a lighting circuit diagram of a high-pressure discharge lamp with a built-in starter device, and Figure 2 is the original! FIG. 3 is a front view of the main parts showing an example of a starting device used in a high-pressure discharge lamp, FIG. 3 is a side view of the same, and FIG. . DESCRIPTION OF SYMBOLS 1...Discharge tube, 2...First bimetal switch, 3...Second bimetal switch, 4...Starting auxiliary conductor, 5... ...Resistor, 6...Outer sphere.

Claims (1)

[Claims] 1. A first starting auxiliary circuit consisting of a discharge tube, a starting auxiliary conductor provided on the outer surface of the discharge tube, and a first bimetal switch connected in parallel with the discharge tube, a resistor and a first bimetal switch. A second starting auxiliary circuit consisting of a series body with a second bimetal switch is provided inside the outer sphere, and the return time of the first bimetal switch is set to be shorter than the return time of the second bimetal switch. A high-pressure discharge lamp with a built-in starting device.