JP2530724Y2 - Discharge lamp for UV irradiation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a discharge lamp for a photochemical reaction, and relates to an improvement in a locking portion of a tubular filter in a water cooling jacket used for the discharge lamp.

[Prior Art] As a discharge lamp for ultraviolet irradiation for photochemical reaction,
A discharge lamp using a water-cooled jacket as described in -197743 has been proposed.

FIG. 3 is an enlarged sectional view of a main part of the water-cooling jacket. In the figure, reference numeral 21 denotes an inner tube, and a tubular filter 22 made of a low-melting glass that transmits ultraviolet rays and absorbs heat rays is fitted around the inner tube and fixed. . One end of the filter 22 is locked to a projection 23 welded to the inner tube 21 in advance, and the other end is locked to the inner end of a locking piece 24 whose outer end is welded to the inner tube. . 25a, 25
Reference numerals b and 25c denote protrusions provided at appropriate positions on the inner tube to prevent the tubular filter 22 from being biased in the lateral direction.

However, in the above-described structure, the thermal effect on the tubular filter during manufacturing is taken into consideration, but when the discharge lamp is lit, water is circulated in the water cooling jacket to cool the arc tube. No consideration is given to the water hammer phenomenon. Further, there is a drawback that skill is required for welding the locking piece to the inner tube.

[Problem to be Solved by the Invention] As described above, conventionally, no consideration has been given to the water hammer phenomenon in the water-cooled jacket. This causes water leakage due to breakage of the tubular filter or cracking of the inner tube, resulting in a use failure. In addition, there is a problem that skill is required for manufacturing.

Means for Solving the Problems The present invention has been made in view of the above, and is characterized in that at least one end of a tubular filter is locked via a tubular spacer made of heat-resistant glass.

With such a configuration, it is possible to prevent the water cooling jacket from being damaged or the tubular filter from falling off due to the water hammer phenomenon, and to provide a long-life discharge lamp.

[Example] Hereinafter, an example according to the present invention will be described with reference to the drawings.
In the present invention, as shown in FIG. 1, a water-cooled jacket 4 made of heat-resistant glass comprising an inner tube 2 and an outer tube 3 is provided on the outer periphery of an arc tube 1 that emits ultraviolet rays. A low-melting glass tubular filter 5 that transmits ultraviolet rays and absorbs heat rays is attached, and the locking portion of the tubular filter 5 is a second filter.
The structure is as shown in the figure. One end of the tubular filter 5 is locked by a projection 6 welded to the inner tube 2 in advance, and the other end is locked by a locking projection 8 via a tubular heat-resistant glass spacer 7.

Numerals 9a, 9b and 9c are other projections welded to the outer surface of the inner tube 2 to prevent the tubular filter 5 and the tubular spacer 7 from being biased in the radial direction.

According to such a structure, when the locking projections 8 are welded to the inner tube 2, a portion remote from the end of the tubular filter 5 may be heated and melted. Damage and stress can be eliminated, and sufficient heat melting work can be performed without skill, so that the projections can be firmly welded and the projections do not fall off even with the water hammer phenomenon. Absent.

The tubular spacer may be provided at both ends. or,
The length of the tubular spacer may be appropriately selected in consideration of the length of the tubular filter and the inner tube.

[Effects of the Invention] As is clear from the above description, in the discharge lamp according to the present invention, the welding operation of the locking projections is easy, and the fusion between the inner tube and the locking projections is completely performed. Therefore, there is an advantage that the locking projections do not fall off, the tubular filter or the inner tube is damaged, and the life of the inner filter is long.

[Brief description of the drawings]

1 is a partially longitudinal side view of a discharge lamp according to the present invention, FIG. 2 is an enlarged sectional view of a main part of a water cooling jacket, and FIG. 3 is an enlarged sectional view of a main part of a conventional water cooling jacket. DESCRIPTION OF SYMBOLS 1 ... Emission tube, 2 ... Inner tube for water-cooled jacket, 3 ... Outer tube for water-cooled jacket, 4 ... Water-cooled jacket, 5 ... Tube filter, 6 ... Protrusion for locking, 7 ... Tube spacer
8 ... locking projections, 9a, 9b, 9c ... projections.

Claims (1)

(57) [Scope of request for utility model registration] 1. A water-cooled jacket 4 made of heat-resistant glass comprising an inner tube 2 and an outer tube 3 on the outer periphery of an arc tube 1 that emits ultraviolet rays.
And a low-melting-point glass tubular filter 5 attached to the outer periphery of the inner tube 2. At least one end of the tubular filter 5 is locked via a heat-resistant glass tubular spacer. Discharge lamp for UV irradiation.