JPS6143802B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a discharge lamp device equipped with a low-pressure discharge tube filled with mercury and a rare gas.

In general, the rare gases sealed together with mercury in low-pressure discharge tubes have the advantage that the larger the atomic weight, the higher the wrap efficiency and the lower the starting voltage.
Recently, neon Ne mainly based on Krypton Kr,
It has been done to fill in a mixed gas such as argon or to mix xenon Xe. However, on the other hand, there is a problem in that flickering due to moving stripe discharge peculiar to rare gases occurs at relatively high ambient temperatures as the atomic weight becomes larger.The present invention was made in view of the above points.

Another cause of flickering is end flicker, which occurs when the dark area formed near the cathode flickers at twice the frequency of the power supply, but this can be easily resolved with a flickerless circuit. Therefore, it is an object of the present invention to prevent flickering occurring over the entire area of the positive column as described above.

Figure 1 shows the relationship between the ambient temperature at which flickering due to moving striped discharge occurs in the positive column and the type of enclosed noble gas.For example, with argon gas, flickering occurs at a low temperature of 0 to 5°C, but with krypton gas, flickering occurs at room temperature. Occurs nearby. The reason may be as follows. That is, the mercury vapor pressure within the discharge tube changes exponentially with temperature, while the ionization voltage of the rare gas decreases as the atomic weight increases. When the ambient temperature decreases, the mercury vapor pressure decreases, and the ions in the tube shift from mercury ions to rare gas ions, causing movement stripes due to rare gas discharge. Because the difference in ionization voltage with the larger krypton (ionization voltage 13.9V) is small, the transfer of rare gas ions takes place at a relatively high ambient temperature with some mercury vapor remaining in the tube.

It has been confirmed that when the filled gas is a mixture of various rare gases, the occurrence of flickering is affected by the heaviest rare gas, and the higher the amount of this heavy rare gas mixed in, the higher the ambient temperature. There is.

In order to suppress the flickering phenomenon of the positive column as described above, the inventors have found that it is effective to apply a magnetic field that crosses the direction of the electric field of the discharge tube over almost the entire area of the positive column. . For example, as shown in Figure 2, a tube with a diameter of 26 mm and a tube length of 1200 mm is filled with a mixed gas of 75% krypton and 25% argon at 1.5 Torr.
A permanent magnet 2 or an electromagnet is placed at one location on the circumference of a straight fluorescent discharge tube 1 of mm length, covering almost the entire length in the longitudinal direction. An orthogonal magnetic field H is applied to almost the entire area of the positive column, and the relationship between the time required for flickering to stop after lighting and the ambient temperature is determined by measuring the strength of the magnetic field at the outer wall of the discharge tube closest to the magnet from 300 to 1200 G ( Gaussian), the result is as shown in Fig. 3. The figure shows that, for example, in the case of an applied magnetic field of 300 G, flickering does not disappear even if time passes when the ambient temperature is 5° C. or lower.

As is clear from Figure 3, with conventional lamps without a magnetic field, flickering does not stop at all when the ambient temperature drops to around 10°C, and even at room temperature (15°C) it takes 5 to 10 minutes to stop flickering. However, according to the present invention, if a magnetic field of 800G is applied, for example, the flickering will completely stop immediately after lighting even at an ambient temperature of 10°C, and it will take about 3 to 4 minutes even at an ambient temperature of 5°C.
Flickering completely stops within minutes, so it can be put to practical use, and even in extremely cold regions, if a 1200G magnet is used, flickering disappears immediately after lighting even at 0°C, making it sufficiently effective.

Furthermore, according to the present invention, as shown in the table below, efficiency can be greatly improved. That is,
Comparing the case of applying a 500G magnetic field to the conventional case of no magnetic field, the lamp current decreases by about 7%, so ballast loss can be reduced by about 15%, and the lamp luminous flux increases by about 10%. Lamp efficiency and overall efficiency are greatly improved. This is thought to be due to the fact that the discharge path inside the tube is expanded in the direction of the tube wall by the magnetic field, promoting ion recombination on the tube wall and increasing the potential gradient of the positive column, thereby increasing lamp luminous flux and lamp efficiency. It will be done.

Conventional (0G) Invention (500G) Lamp current 100% 92.6% Lamp voltage 100% 112.6% Lamp power 100% 105.1% Lamp luminous flux 100% 109.5% Furthermore, the lamp luminous flux of the above embodiment (500G) and conventional example (0G) Figure 4 shows a comparison of the rise characteristics.
As is clear from the figure, in the conventional case without a magnetic field, it took about 10 minutes for the luminous flux to reach a steady state, whereas according to the present invention, the luminous flux reached 100% in 3 to 4 minutes.
%, indicating that the rise characteristics are extremely excellent.

In FIG. 2, a permanent magnet 2 is used as a magnetic field generating means, and a strip-shaped permanent magnet 2 is attached to a reflecting plate 5 attached to the instrument body 3 with a mounting bracket 4, and the lower surface of both ends of the instrument body 3 is attached. The permanent magnet 2 is arranged to face the tube wall of the fluorescent discharge tube 1 installed between the sockets 6 protruding from the device body 3, for example.
An appropriate number of electromagnets magnetized in the same direction by a DC power source may be arranged at appropriate intervals within the chamber. Fifth
The figure shows an example in which an annular permanent magnet 2 is fixed to the fixture body 3 of a round fluorescent lamp fixture, and Fig. A magnet 2 is attached to apply a magnetic field to the two discharge tubes 1.

The present invention is configured as described above, and can prevent flickering due to moving stripes peculiar to rare gas discharge and improve lamp efficiency. It has the advantage that the flicker and ballast loss at low temperatures do not increase as in the case of This has the advantage that flickering can be prevented even if there are places where the magnetic field is weak locally due to heat or intermittently arranging electromagnets.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the principle of the present invention, Fig. 2a is a perspective view of an embodiment of the invention, b is a broken perspective view of the main parts of the same, c is a sectional view of the main parts of the same, Figs. FIG. 4 is an explanatory diagram of the same operation as above, and FIGS. 5 and 6 are perspective views showing various embodiments of the present invention. 1 is a discharge tube, 2 is a permanent magnet, 3 is a device body, 4
is the mounting bracket, 5 is the reflector, and 6 is the socket.

Claims (1)

[Claims] 1. In a device equipped with a low-pressure discharge tube filled with mercury and a rare gas, a magnetic field generating means installed along the tube wall of the discharge tube generates a static magnetic field that intersects with the electric field inside the discharge tube, approximately in the positive column. A low pressure discharge lamp device formed over the entire area.