JPS617558A - Fluorescent lamp - Google Patents

Abstract

PURPOSE:To prevent a fluorescent lamp from failing to ignite by improving the electromotive effect of a high-frequency lighting circuit used for a lantern or similar device by adjusting the internal gas pressure of the lamp to at least a specified level. CONSTITUTION:In a high-frequency lighting circuit in which batteries are used as a power supply and which is used for a lantern or similar device, a luminous point occurs in the filament immediately after the start of electric discharge and a lighting state of normal electric discharge is not produced until the luminous point disappears and electricity is discharged from either the whole electrode or around a lead wire supporting the filament. The above occurrence of the luminous point can be prevented by maintaining the internal gas pressure of the lamp at a level of at least 6Torrs. Consequently, electricity is easily discharged from the whole electrode or around the lead wire from the initial stage, thereby improving the electromotive effect of the high-frequency circuit.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to the improvement of a small fluorescent lamp, and more particularly, the present invention relates to the improvement of a small fluorescent lamp, and more specifically, it has a high-frequency lighting circuit and is used in a lantern or the like powered by a dry battery or a car battery.ノ”1
This invention relates to improving the start-up performance of fluorescent lamps.

[Background of the invention]

Conventionally, for example, /J) type fluorescent lamps with a tube length of 30 cm or less as described in Japanese Utility Model Application Publication No. 54-131777, mainly 4 Watt, 6 Watt, and 8 Watt type fluorescent lamps, have been used as lighting circuits with ordinary fluorescent lamps. Similarly, since the lamp was lit using a ballast, the structure was designed to obtain the best characteristics when using a ballast. For example, the pressure of the gas sealed inside the lamp is about 5 Torr for a small fluorescent lamp. be. In such small fluorescent lamps, the gas to be filled is mainly argon gas or the like.

However, in recent years, so-called lanterns have become popular, which do not require such a ballast and have a high-frequency lighting circuit that can be used on low-voltage power sources such as dry batteries or car batteries. When a high-frequency lighting circuit was used to turn on the light, a problem arose in that the light would no longer turn on after repeated blinking. This non-lighting is noticeable at low voltages that are at the limit of the specified voltage. In particular, when a dry cell battery is used as a power source, the voltage drops as the battery wears down, which increases the number of such failures.

[Purpose of the invention]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a compact fluorescent lamp for high frequency lighting which eliminates the above-mentioned problems.

[Summary of the invention]

In order to achieve the above object, the present invention uses a high frequency 7 lighting circuit to light a small fluorescent lamp with a tube length of 30 cm or less, and the inert gas pressure in the fluorescent lamp is at least 6 Torr. It is characterized by comprising a lamp.

Owing to the characteristic configuration of the present invention, it has become possible to provide a compact fluorescent lamp that solves the conventional problems.

That is, the present invention was made based on the following facts.

Generally, in a lighting circuit using a ballast, lowering the pressure of gas entering the lamp facilitates mercury discharge and improves start-up performance. When one light is turned on, a bright spot is created at a certain point on the filament of the electrode. On the other hand, in high-frequency lighting circuits used in lanterns, etc., a bright spot forms on the filament immediately after the start of discharge, and then this bright spot disappears from the entire electrode or near the lead wire holding the filament. Normal discharge lighting occurs only when the battery is completely discharged. Therefore, in fluorescent lamps for high-frequency lighting circuits used in lanterns, etc., by increasing the pressure of the gas filled in the lamp, the above-mentioned bright spot is prevented from forming in the first place, and the discharge starts at the electrodes. It is presumed that starting performance is improved because it is more likely to be formed overall or near the lead wire.

[Embodiments of the invention]

Hereinafter, the present invention will be explained in detail with reference to Examples. 1st
The figure shows an example of a high-frequency lighting circuit for lighting a lantern used in lighting tests in carrying out the present invention. The DC voltage from a DC voltage power source 1 such as a dry battery or an automobile battery is converted into a high frequency voltage of several tens of KHz by an inverter 2 and is applied between the electrodes 4 and 4' of a small fluorescent lamp 3 with a tube length of 30 cm or less. Ru. the result,
A discharge is started between the electrodes 4 and 4', and the fluorescent lamp 3 is turned on. Some inverters employ a method in which one electrode 4' of the fluorescent lamp 3 is made part of the circuit of the inverter 2, as shown in Figure 1, or a method in which both electrodes 4 and 4' are made part of the circuit. be. Further, since the circuit and function of the inverter 2 are well known, a description of its operation will be omitted.

The results of various lighting tests performed on the above-mentioned lantern lighting circuit will be described below.

FIG. 2 shows the areas of 4 watts, 6 watts, and 8 watts of lighting and non-lighting. It is clear from this diagram,
It can be seen that the pressure of the gas sealed inside the uni lamp is 6 Torr or more and it can be used practically without any problem. FIG. 3 shows the relationship between the argon gas pressure sealed in the lamp and the voltage at which the lamp is lit at a room temperature of 25° C. (abbreviated as lighting voltage) in a general circuit using a ballast. When using a ballast, the lighting voltage increases as the gas pressure inside the lamp increases, and from Figure 3, the gas pressure inside the lamp is 12 to 14T.
It is assumed that there will be no particular problem even if there is a level of orr. However, at lower temperatures, the lighting voltage will increase from 25℃, and if the gas pressure inside the lamp is too high, the luminous flux will decrease. When the gas flows in, there are problems such as the phosphor exfoliating due to the high speed of the gas. Overall, it was found that the upper limit of the filled gas pressure is 1 Torr.

In other words, in order to create a compact fluorescent lamp that can be lit both with a high-frequency lighting circuit and with a conventional ballast, it is necessary to set the pressure of the inert gas in the range of 6 to 11 Torr.

〔Effect of the invention〕

As explained above, the present invention improves starting performance in high-frequency lighting circuits used in lanterns, etc. by setting the gas pressure in the lamp to at least 6 Torr, and eliminates non-lighting accidents. 6-11. Tor
By setting it to r, there are advantages such as being able to use it even in a circuit using a ballast.

[Brief explanation of drawings]

Figure 1 is a block diagram of a high-frequency lighting circuit used in a lantern, Figure 2 is a graph showing the lighting and non-lighting areas in relation to the number of blinks in the high-frequency lighting circuit and the filled gas pressure, and Figure 3 is It is a graph showing the relationship between 25° C. lighting and the gas pressure sealed in the lamp in a circuit using a ballast. ■...DC power supply, 2...Inverter, 3...Fluorescent lamp, 4,4'...Electrode. Agent, -Patent Attorney Katsuo Ogawa"fJ 1 Figure

Claims (1)

[Claims] 1. The length of the tube that lights up using a high frequency lighting circuit is 30cm.
The following compact fluorescent lamp, characterized in that the pressure of the inert gas in the fluorescent lamp is at least 6 Torr.