JPS5825070A - Low pressure vapor discharge lamp - Google Patents

Abstract

PURPOSE:To stabilize two-stripe discharge in the space enclosed between the outside and inside glass tubes of a discharge lamp consisting of an inner and outer double glass bulb by narrowing the tip of the inside glass tube smaller than its inner diameter, while forming an opening. CONSTITUTION:An inside bulb 2 whose tip is formed as a circular opening 3 by narrowing the tip is arranged inside a spherical outside glass bulb 1 and is fixed airtightly to the flare 7 of a stem 4 which supports a filament cathode 5 using inorganic adhesives. Besides, a discharge lamp is formed by providing a number of anodes 6 and 6' at the flare so that 7 they may be positioned outside the inside bulb 2 and inside the outside bulb 1, applying a phosphor to the inner surface of the outside bulb 1 and the outer surface of the inside bulb 2, and sealing rare gas and metals. As a result, by narrowing the tip of the inside bulb 2 while forming an opening, a two-stripe discharge path in a space can be stabilized and the brightness of a lamp can be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Field of Application of the Invention The present invention relates to a discharge lamp with a discharge vessel consisting of an inner and outer glass bulb, in which the tip of the inner glass tube is narrowed and the outer glass bulb and the inner glass tube are separated. This invention relates to a small-sized low-pressure steam discharge lamp in which a plurality of stable discharge paths are formed in a surrounding discharge space. A single-cap light bulb type rechargeable/discharge lamp is a typical application example of the present invention.

(2) Prior art Conventional lighting rechargeable discharge lamps generally have a structure in which electrodes are installed at both ends of a long and thin glass tube, but such long discharge lamps are inconvenient to handle depending on the situation, and the length There was a desire to develop a small, bright discharge lamp with a short length.

The present inventors have already made a proposal in line with the above-mentioned purpose. In other words, the outline is that the discharge vessel has a double inner and outer tube structure, with a cathode installed inside the inner glass tube, multiple anodes installed at the bottom between the outer glass bulb and the inner glass tube, and an inner glass tube with a cathode installed inside the inner glass tube. A notch was provided at the tip of the tube at a position corresponding to the anode to form a stable multi-line discharge path. The purpose of the present invention is to further improve this discharge lamp.

(3) Purpose of the invention In discharge lamps with double inner and outer tubes, it is difficult to fill the discharge space surrounded by the outer and inner tubes with uniform plasma. We proposed a low-pressure steam discharge lamp with multiple discharge paths by providing a notch. This notch at the tip of the inner tube is a process that is difficult to adapt to manufacturing of discharge lamps, especially mass production, and one of the objects of the present invention is to improve this point.

The second objective is to develop a compact low-pressure steam discharge lamp that has the function of increasing the illuminance on the bottom surface when actually lit and the function of improving the color of the emitted light.

(4) General description of the invention In a discharge lamp with a double inner and outer tube structure, a cathode is provided in the inner glass tube and a plurality of anodes are provided in the outer glass bulb, and the tip of the inner glass tube is narrowed to be smaller than the inner diameter of the glass tube. 〇(5) Example The present invention will be explained in detail with reference to an example below.
The figure shows an embodiment of the present invention, in which an outer glass bulb 1
is a spherical glass bulb with a tube diameter of 125 mm. The inner glass bulb has a tube diameter of 30 mm and a length of 115 mm, and a narrow circular opening 3 is provided at the tip. Although not shown, the inner surface of the outer glass bulb 1 and the inner and outer surfaces of the inner glass bulb 2 are coated with a phosphor.

The stem 4 is a filament cathode 5 coated with an electron emitting material.
Further, a flare 7 is provided at the intermediate portion of the stem 4, and the inner glass bulb 2 is adhesively fixed with an inorganic adhesive. Two anodes 6, 6' are also supported at this flare 7. The discharge tube having the above structure is exhausted by an exhaust pipe 8, and is filled with a rare gas at a required pressure and a small amount of mercury.

This discharge lamp is lit by a circuit consisting of a ballast 9, a diode bridge rectifier 10, and a glow lamp 11, as shown in the figure.

t) The diameters of the opening 3 at the tip of the inner glass tube 2 of the # electric lamp used in the experiment were 2.5 mm, 5 mm, 10 mm, 1
One was squeezed to 5 mm and 20 mm, and the other was 30 mm (not squeezed). Argon 2.7 as filler gas
When Torr and mercury were sealed, the hole was narrowed (2.5 m
20 mm) all have the appearance that plasma is ejected from inside the inner glass tube 2 through the aperture 3, and two stable discharge paths are formed in the space surrounded by the outer glass bulb 1 and the inner glass tube 2. did.

On the other hand, do not squeeze the tip of the inner glass tube (30mm)
In discharge lamps, the discharge was unstable and wavered.

In addition, the plasma ejected from the constricted opening 3 has high brightness, which is approximately 10 times brighter in discharge lamps with 2.5 mmφ and 5 mmφ apertures compared to the plasma at the same position in discharge lamps without constricted holes. It was confirmed that the brightness was .

Generally, when the lamp is lit in the base-up position, the tip of the discharge lamp is at the bottom,
The illuminance on the bottom surface is substantially increased, and the practical effect is great. Furthermore, when 6 Torr of neon is filled in as the filler gas, the plasma ejected from the opening 3 emits neon red light, and even in lamps using inexpensive halo phosphors, the emitted light has a reddish color, giving a pleasant feeling. There is 0 (6)
Summary According to the present invention, by providing a narrow opening at the tip of the inner glass tube in a discharge lamp consisting of a discharge vessel with a double inner and outer tube structure, two It was shown that a striped discharge path was formed and that the striped discharge path was stable. The narrow opening at the tip of the inner glass tube can be easily made by heating with a burner, for example, and there is no problem in applying it to mass production.

Furthermore, in this example, the opening at the tip of the inner glass tube was circular as shown in Figure 2, but it is not necessarily limited to a circular shape, and as shown in Figure 3, for example, it may be deformed into an almost oval shape. There is no problem even if you do.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the present invention, FIG. 2 is a top view of the tip of the inner glass tube of the present invention, and FIG. 3 is a diagram showing another embodiment of the tip of the inner glass tube. be. l...Outer glass bulb, 2...Inner glass bulb, 3...Narrowed opening, 4...Stem, 5
...Cathode, 6...Anode, 7...Flare, 8
...Exhaust pipe, Patent attorney Toshiyuki Usuda ;・'” Denial-1 mouth “-11-”” H--“ O Figure 2

Claims (1)

[Claims] 1. A rare gas or a rare gas and a metal are sealed in a discharge vessel consisting of an inner and outer double glass bulb with an inner glass tube installed almost coaxially within the outer glass bulb, and a plurality of cathodes are placed inside the inner glass tube. The anodes are installed outside the inner glass tube and inside the outer glass bulb, and the tip of the inner glass tube has an aperture narrowed to be smaller than the inner diameter of the inner glass tube. A low-pressure steam discharge lamp.