JPH0575957U - Discharge lamp - Google Patents

Abstract

(57) [Summary] [Purpose] To stably fix the amalgam metal in the arc tube near the coldest spot. [Structure] At least mercury is enclosed in a light-transmitting arc tube 1, and a predetermined amount of an amalgam metal 5 for controlling the mercury vapor pressure is enclosed. The amalgam metal 5 is wrapped with a metal mesh 4 and fixed to the back surface of the heat shield plate 3 mounted on the stem 2 in the arc tube 1.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a discharge lamp that discharges and emits mercury vapor enclosed in an arc tube.

[0002]

[Prior Art]

 In a mercury-filled discharge lamp, it is important to control the mercury vapor pressure. When the discharge lamp becomes hot, the mercury vapor pressure rises, exceeds the optimum vapor pressure, and the efficiency drops. .

As a solution to this problem, by welding amalgam metal to the glass surface near the coldest point in the arc tube, the mercury vapor pressure in the arc tube can be controlled within an appropriate range even when the discharge lamp is at a high temperature. Are known.

[0004]

[Problems to be solved by the device]

 However, in recent years, discharge lamps have become smaller and have higher output, and since this type of lamp is operated under a relatively high load, the lamp usually has a high temperature during lighting. Therefore, just by welding the amalgam metal to the glass surface as described above, the amalgam metal melts and drops from the glass surface. Also, it may fall due to external vibration or shock.

When the amalgam metal drops from the glass surface, it damages the fluorescent film applied to the inner surface of the arc tube, and the problem that the amalgam metal is not fixed at the coldest spot and the lamp characteristics are not stable. There is.

The present invention has been made in view of the above problems, and an object thereof is to provide a discharge lamp in which the amalgam metal in the arc tube is stably fixed near the coldest point.

[0007]

[Means for Solving the Problems]

 In order to solve the above problems, the present invention relates to a discharge lamp in which at least mercury is enclosed in a translucent arc tube and a predetermined amount of amalgam metal for controlling the mercury vapor pressure is enclosed. It is characterized in that it is wrapped in a metal mesh and fixed to the back surface of the heat shield plate attached to the stem in the arc tube.

[0008]

[Action]

 With the above structure, the amalgam metal in the arc tube is stably fixed near the coldest point even if it melts at the temperature when the lamp is on.

[0009]

【Example】

 FIG. 1 shows an embodiment of the present invention, in which the lamp is an electrodeless discharge lamp. In the figure, reference numeral 1 denotes a light bulb-shaped arc tube made of glass, a fluorescent film (not shown) is applied to the inner surface, and a discharge gas such as mercury is sealed inside. Reference numeral 3 denotes a heat shield plate attached to the stem 2 in the arc tube 1, and an amalgam metal (not shown) wrapped with a metal mesh 4 is fixed to the back surface, that is, the low temperature side.

Next, a method of fixing the amalgam metal wrapped with the metal mesh 4 to the heat shield plate will be described with reference to FIG. First, a metal mesh 4 and an amalgam metal 5 as shown in FIG. 2 (a) are prepared, and the amalgam metal 5 is wrapped with the metal mesh 4 in a tubular shape as shown in FIG. 2 (b). Then, one end of the tubular metal mesh 4 is fixed to the heat shield plate 3. The heat shield plate 3 is formed with a notch 6 for mounting the stem.

With this configuration, the amalgam metal in the arc tube 1 is stably fixed near the coldest point even if it melts at the temperature when the lamp is on. Therefore, unlike the conventional case, there is no risk of damaging the fluorescent film due to the fall of the amalgam metal, and the amalgam metal can be reliably fixed in the vicinity of the coldest point in the arc tube 1, so that the characteristics of the lamp are stabilized.

[0012]

[Effect of the device]

 According to the present invention, as described above, the amalgam metal is wrapped in the metal mesh and is fixed to the back surface of the heat shield plate attached to the stem in the arc tube. , Stable and fixed near the coldest point. Therefore, according to the present invention, it is possible to provide a discharge lamp that has stable lamp characteristics without the risk of damaging the fluorescent film.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 is a perspective view showing a method of fixing an amalgam metal wrapped with a metal mesh to a heat shield plate.

[Explanation of symbols]

 1 arc tube 2 stem 3 heat shield plate 4 metal mesh 5 amalgam metal 6 notch

Claims (1)

[Scope of utility model registration request] 1. A discharge lamp in which at least mercury is enclosed in a light-transmitting arc tube and a predetermined amount of amalgam metal for controlling the mercury vapor pressure is enclosed, and the amalgam metal is wrapped with a metal mesh. A discharge lamp characterized by being fixed to the back surface of a heat shield plate mounted on a stem in an arc tube.