JPH0334834Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to the structure of a heat-retaining heater for a fluorescent lamp for a copying machine.

The brightness of the exposure fluorescent lamp used in a copying machine affects the finish of copies, so stabilizing it is the most important condition for the performance of the copying machine.

Generally, the brightness of a fluorescent lamp depends on the temperature inside the lamp tube, so the brightness at the beginning of lighting tends to be low and gradually increase. Therefore, the fluorescent lamps in copying machines are always heated to a constant temperature by some kind of heater in order to always obtain a constant brightness. Heaters conventionally used for this purpose are shown in FIGS. 4 and 5.

That is, a sheet heater in which a cord-shaped heater is placed between two sheets of aluminum foil is attached with adhesive directly above a fluorescent lamp. Fluorescent lamps are therefore expensive and uneconomical. Another disadvantage is that the adhesive for fixing the heater changes color when exposed to fluorescent light, resulting in a decrease in illuminance and decomposing, producing harmful gases.

The fluorescent lamp heating device for a copying machine of the present invention includes a case 1 made of a thermal insulator, a cord-shaped heater 3 fitted into a groove 4 provided in the case and wired, and a cord heater 3 provided on both edges of the case. It consists of a metal plate 2 having a curved surface fitted into a groove 8.

In addition, the case surface in which the heater is embedded has a curvature,
Both the curvature and the curvature formed by the metal plate are designed to be approximately equal to the tube wall curvature of a fluorescent lamp.

The fluorescent lamp heating device for copying machines of the present invention is installed in a lamp so that the metal plate surface is in close contact with the fluorescent lamp tube surface. The heat emitted from the cord-shaped heater heats the fluorescent lamp via a metal plate with good thermal conductivity.

Since the tube surface of a fluorescent lamp is in close contact with a metal plate having approximately the same curvature, the amount of heat emitted from the cord-shaped heater is transmitted to the lamp tube surface with little loss. Also, by using a metal plate with good thermal conductivity, the entire contact surface has a uniform temperature distribution. The second advantage is that the light reflected by the metal surface can be effectively used as a light source. The third advantage is that there is no adhesive at the bonding part between the light tube and the metal plate surface, so there are no problems caused by this. A fourth advantage lies in the structure of the heating device of the present invention. As mentioned above, the fact that the main body is made of a thermal insulator and has a heater wiring groove makes it extremely easy to wire the heater, eliminating the need for wiring jigs and tools required in conventional methods, and reducing man-hours. It can be drastically reduced and the heat can be used effectively. In addition, the fact that the wiring surface has a curvature that is approximately the same as the wall surface of the light tube means that the curvature is approximately the same as that of the metal plate to which it is fitted, making it possible to press the entire surface tightly against the metal plate and to fix the heater without the need for adhesives. It is necessary and has good thermal efficiency. Furthermore, the metal plate surface has both the effect of providing uniform heat distribution and the effect of acting as a reflective surface.

The fluorescent lamp heating device for a copying machine according to the present invention can be manufactured extremely economically, eliminates all the drawbacks of the conventional devices, and is of high practical value.

[Brief explanation of the drawing]

Figure 1 is a perspective view of the present invention, Figure 2 is a case of the present invention, Figure 3 is a sectional view taken along line A-A' in Figure 2, Figure 4 is a front view of the conventional product, and Figure 5 is the case of the present invention. BB' sectional view of the figure. 1... Case, 2... Metal plate, 3... Cord-shaped heater, 4... Groove, 5... Fluorescent lamp, 6... Aluminum foil, 7... Adhesive, 8... Metal plate fitting groove.

Claims (1)

[Scope of utility model registration request] A case made of a thermal insulator and having a curvature approximately equal to the tube wall of a fluorescent lamp, a cord-shaped heater fitted into a groove provided in the case, and a cord-shaped heater fitted into the case by utilizing the repulsion properties of metal. A fluorescent lamp heating device for a copying machine comprising a metal plate fixed to a case, fitted into grooves provided on both edges of the case, and having a curvature approximately equal to the tube wall of the fluorescent lamp.