JPH08330159A - Ballast for discharge lamp - Google Patents

Abstract

PURPOSE: To facilitate the degassing even for a long tubular case by employing a hollow pipe provided, on the outer circumferential part, with a pawl for stopping a ballast body and passing through a filler. CONSTITUTION: A bottom cover 2 is fitted to one of the opposite openings of a tubular case 1 housing a ballast body 3 filled with a filler 6 on the circumference. The joint between the bottom plate 2 and the case 1 is coated with an adhesive 5 for preventing leakage of the filler. A hollow pipe 4, having one end communicating with the outside, is buried in the filler 6. Vents 11 are made in the hollow pipe 4 at the parts buried in the filler 6 and sealed with a closing member 10 being opened by the pressure of gas generated from the filler 6. The hollow pipe 4 is provided, on the outer surface, with pawls 12 which stop on the end face of ballast body 3. The hollow pipe 4 communicates with the outside of opening through the inner end face of bottom cover 2 in the tiller 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge lamp ballast having a structure in which a ballast body is housed in a case and filled with a filling material. In particular, it relates to a structure for releasing gas generated from the filler and a structure for preventing movement of the ballast main body due to gas generation and expansion.

[0002]

2. Description of the Related Art A conventional structure shown in FIG. 3 will be described. Abnormal heat generation of the ballast body 3 causes troubles caused by the gas generated from the filler 6 inside the case 1. To prevent this, the bottom cover 2 of the case 1 has a gas vent hole 1
3 is provided, and this is sealed with a closing member 10 that can be opened by gas pressure to prevent leakage when the filler 6 is injected.

[0003]

In the above-mentioned prior art, in the case 1 having a long cylindrical shape, the gas generated from the entire filling material 6 is filled with the degassing hole 13 provided in the bottom cover 2 and the filling material 6.
However, it was difficult to release the gas generated from the central portion of the case 1. An object of the present invention is to provide a ballast for a discharge lamp capable of easily venting gas even in a long cylindrical case.

[0004]

In order to achieve the above-mentioned object, the present invention uses a hollow pipe which is provided with cut-and-raised pawls which communicate with the inside of the filling material and engage with the ballast body in the outer peripheral portion. To do.

[0005]

With the above-mentioned structure, the gas generated from the entire filling material in the ballast case leaks into the pipe through the ventilation hole of the hollow pipe and is discharged to the outside.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of FIGS. 1 and 2 according to the present invention will be described. FIG. 1 is a cross-sectional view of the case-containing ballast from the side surface, and FIG. 2 is a cross-sectional view from the end surface. In this embodiment, the bottom cover 2 is fitted into one of both openings of the cylindrical case 1 to store the ballast main body 3 inside the case 1, and
The periphery of the ballast body 3 is filled with the filling material 6. An adhesive 5 for sealing is applied to the joint between the bottom cover 2 and the case 1 to prevent leakage of the filler. A hollow pipe 4 is provided which is embedded in the filling material 6 and has one end communicating with the outside. The hollow pipe 4 is provided with a ventilation hole 11 in a portion embedded in the filling material 6, and the ventilation hole 11 is sealed by a closing member 10 which is opened by a gas pressure generated from the filling material 6. Further, the locking claw 12 provided on the outer surface of the hollow pipe 4 is locked to the end surface of the stabilizer main body 3. A supplementary explanation will be given. The hollow pipe 4 communicates from the inner end surface of the bottom lid 2 inside the filler 6 to the outside of the opening. The ventilation holes 11 are provided at equal intervals. The end of the hollow pipe 4 on the bottom lid 2 side is also closed by the closing member 10. Ballast body 3
The ballast main body 3 is provided between the locking claws 12 cut and raised to fit the entire length.
Lock. There are two hollow pipes 4, and the ballast body 3 is sandwiched between them. 7 is an insulating paper between the case and the coil. The gas generated from the filling material 6 in the case 1 breaks through the ventilation hole 11 that opens when the pressure exceeds a certain level, which adversely affects the ballast body 3, and is discharged to the outside through the hollow pipe 4. As a result, it is possible to supply a highly reliable product free from troubles such as expansion of the filling material 6 due to gas and internal disconnection due to cracks and distortion of the coil.

[0007]

According to the present invention, in order to release the gas generated from the filling material, a hollow pipe extending along the longitudinal direction of the case is passed through, so that the filling material inside the case can be discharged from the filling material when the temperature of the ballast body rises abnormally. The generated gas leaks into the hollow pipe through the nearest ventilation hole and is easily discharged to the outside. Moreover, since the ballast body is locked by the locking claws cut and raised in the hollow pipe, it is unlikely to be adversely affected by the expansion of the filling material by the gas.

[Brief description of drawings]

FIG. 1 is a sectional view of a ballast for a discharge lamp according to the present invention taken along a longitudinal direction.

FIG. 2 is a sectional view taken along the lateral direction of the ballast of FIG.

FIG. 3 is a sectional view taken along the longitudinal direction of a conventional ballast.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Case, 2 ... Bottom lid, 3 ... Ballast body, 4 ... Gas venting hollow pipe, 5 ... Bottom lid adhesive material, 6 ... Filling material, 7
Insulating paper between case and coil, 8 Insulating paper fixing tape, 9
... Lead wire, 10 ... Adhesive material for preventing leakage of filling material, 11 ... Ventilation hole for venting gas, 12 ... Claw raised for locking ballast body, 13
… Vent holes

Claims (1)

[Claims] 1. A bottom cover is fitted into one of both openings of a cylindrical case to house the ballast body inside the case, and the periphery of the ballast body is filled with a filling material. In a discharge lamp ballast in which a sealing adhesive is applied at the joint of the case to prevent leakage of the filler, a hollow pipe embedded in the filler and having one end communicating with the outside is provided, and the filler in the hollow pipe is provided. A ventilation hole was provided in the inner buried portion, and the ventilation hole was sealed with a closing member that was opened by gas pressure generated from the filling material, and the locking claw provided on the outer surface of the hollow pipe was locked to the end surface of the ballast body. A ballast for a discharge lamp, which is characterized in that