JPS6122555A - Flash lamp unit - Google Patents

Abstract

PURPOSE:To make a unit compact by forming a reflecting layer, by which flash is reflected, on the wall of a flash lamp tube, opposite to the open surface of the tube. CONSTITUTION:A reflecting plate 6 formed so as to cover the wall of a flash lamp tube 1 is mounted on the wall of the tube 1, opposite to the open surface 3. By the reflecting plate 6, a reflecting layer is formed. Forming of electric-conductive reflective surface in the reflecting part of the back side of the flash lamp tube is not necessary, and flash lamp tube 1 and a reflecting part 2 can closely be arranged. Therefore, the reflecting part 2 is made small and a unit is made compact.

Description

[Detailed Description of the Invention] II! In the II image recording apparatus, there is a flash lamp device used for fixing or exposure.

PRIOR ART Image recording devices such as copying machines, facsimiles, and printers often use a flash lamp device for exposure to illuminate the surface of the document, as well as a fixing device for fixing the toner image on the recording paper. Fixing or exposure is performed by a momentary strong flash of light emitted from a flash lamp tube such as a xenon lamp.

8 and 9 show a conventionally used flash lamp device for fixing, which is constructed by covering the periphery of a flash lamp tube 1 with a reflective member 2, and the lower surface of the reflective member 2 is open. It has a box shape, and a transparent plate 3 made of heat-resistant glass or the like is stretched over the open surface. As shown in FIG. 9, the reflecting member 2 is an L-shaped member that reflects the flash light emitted from the flash lamp tube 1 and directs it onto the recording paper 4 placed below the transparent plate 3, and has a low reflectance. (Usually made of metal and grounded.

The flash lamp tube 1 is usually formed into a cylindrical shape using a quartz tube, etc., and is not filled with a gas such as xenon. A flash is emitted by discharging the charge of the capacitor between the electrodes, and this flash lamp tube has a trigger electrode 5 in addition to the discharge electrode.
is provided, and by applying a high trigger pulse voltage to this trigger electrode, the inside of the lamp tube becomes conductive and the above-mentioned discharge phenomenon occurs. As shown in FIG. 8, this trigger me=5 is constructed of a bare high-voltage electric wire [, J:] that is directly wound around the outer periphery of the flash lamp tube 1.

However, in the conventional flash lamp device as described above, it is difficult to prevent current leakage through the high trigger voltage applied to the trigger electrode 5 or through the reflective member 2, which is made of a conductive material such as metal and is grounded. To avoid this, a sufficient space distance F! is provided between the flash lamp tube 1 and the reflective member 2! Usually, it is necessary to set the distance X between the trigger electrode 5 and the reflector plate 2 to be at least 91 times the trigger pressure of about IKV.

Therefore, the placement position of the flash lamp tube in the space surrounded by the reflecting member is restricted, so it is not possible to arrange the flash lamp tube at a position that optimizes the irradiation distribution on the irradiated object, and the reflecting member 2 is made larger. There were problems such as having to do something.

The present invention aims to solve the above-mentioned problems and to enable the flash lamp tube to be arranged sufficiently close to the reflective member. A reflective layer 6 for reflecting flash light emitted from the flash lamp tube is provided on the tube wall portion of the member 2 opposite to the open surface 3.

According to the present invention, the flash of light directed toward the opposite side of the open surface 3 of the Franche lamp tube 1 is prevented by the reflective layer 6 from reaching the open surface 3.
Since the light is reflected to the side, there is no need for a reflective surface behind the flash lamp tube 1. Therefore, by locally constructing 6 parts of 20 pairs of reflection members with an insulating material or cutting them out, a sufficient distance is maintained between the trigger electrode 5 and the conductive part of the reflection member 2 to prevent leakage of the trigger voltage. It is possible to place the flash lamp tube 1 sufficiently close to or in contact with the reflective member 2 while avoiding the need for the reflective member 2.

Embodiment FIGS. 1 to 3 show an embodiment in which the present invention is applied to a flash lamp unit for fixing. A sectional view taken along the line n--■ in the figure, and FIG. 3 is a partially enlarged view of FIG. 2. Similar to the conventional flashlamp device described above with reference to FIGS. 8 and 9, this flashlamp device includes a flashlamp tube 1 and a reflecting member 2, and the lower part of the reflecting member 2 is an open surface. A transparent plate 3 made of heat-resistant glass or the like is stretched over this open surface. A recording paper 4 is conveyed below the transparent plate 3 in the direction of arrow a (FIG. 2), and is irradiated through the transparent plate 3 by a flash 7 emitted from a flash lamp tube 10. For example, in the case of an electrophotographic copying machine, a toner image obtained by developing an electrostatic latent image on a photoreceptor is transferred from the photoreceptor to the upper surface of the recording paper 4. The image is fused by the flash 7 and fixed on the recording paper 4.

A trigger electrode 5 is wound around the outer periphery of the flash lamp tube 1, as in the conventional flash lamp tube 1, but in this embodiment, the upper part of the outer periphery of the flash lamp tube 1, that is, the A reflecting plate 6 processed to cover the tube wall portion is attached to the tube wall portion on the side opposite to the open surface 3, and a reflective layer is formed from this reflecting plate 61C. Therefore, the flash of light emitted upward from the inside of the flash lamp tube l is shown in Figure 2. As shown in , the light is reflected by the inner surface of the reflecting plate 6 and irradiates the transparent plate, that is, the open surface 31C, and onto the recording paper 4.
It is not necessary to make the back part of the lamp tube 1 of the reflective member 2 a reflective surface as shown in FIG. Therefore, in this embodiment, this portion is constructed of an insulating member 8 which is an electrically non-conductor. This insulating member 8 is connected to another conductive portion 21 (third
Although a box-shaped reflective member 2 is formed as shown in FIG. Conductive portion 2. Distance x to the trigger electrode 5 (as mentioned above, it is sufficient to take the third figure at a rate of 1 anus per trigger voltage of about IKV,
The flash lamp tube 1 can be placed close to the inner surface of the reflective member 2. Therefore, since there is no need to provide a sufficient spatial distance between the flash lamp tube 1 and the inner surface of the reflecting member 2, the height of the reflecting member 2 can be reduced, and the entire device can be made smaller. On the main flow side, the height of the reflective member 2 is further reduced by making the insulating member 8 project from the upper surface of the separate member 2 and housing the flash lamp tube 1 in the inner four parts 9 formed by this. I take it as a thing.

The reflective layer 6 provided on the wall portion of the flash lamp tube can be formed by a variety of methods, some examples of which are shown in FIGS. 4 to 7.

The reflective layer 61 shown in FIG.
The reflective layer 62 shown in the figure is made by wrapping and pasting a thin plate-like reflective material onto the surface of the flash lamp tube 10. Trigger electrodes are conventionally attached to these outer peripheral surfaces.

The reflective layer 63 shown in FIG. 6 is a relatively thick reflective plate processed to cover the lamp tube 1 and attached to the tube wall, similar to the embodiments shown in FIGS. 1 to 3.

The reflective layer 64 shown in FIG. 7 is formed by coating the inner surface of the flash lamp tube 1 with a reflective agent.

Effects of the Invention As described above, in the present invention, in a flashlamp device comprising a flashlamp tube surrounded by a reflective member having one open surface, a tube wall of the flashlamp tube opposite to the open surface is provided. Since a reflective layer that reflects the flash light emitted by the flash lamp tube is provided on the part, the reflective member part behind the Franche lamp tube does not need to be a conductive reflective surface, and therefore the flash lamp tube and the reflective member are sufficiently separated. Since they can be brought close together, a relatively small reflective member can be used, and the overall device becomes compact.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a flash fixing device according to an embodiment of the present invention. FIG. 2 is a sectional view taken along the line ■-■ in FIG. FIGS. 4 to 7 are cross-sectional views showing examples of reflective layers, respectively, and FIGS. 8 and 9 are cross-sectional views similar to FIG. 2 and FIG. 2 showing conventional flash lamp devices. 1... Flash lamp tube, 2... Reflective member 23.
... Transparent plate (open surface) 24... Recording paper, 5... Trigger electrode 26... Reflective layer, 7... Flash light, 8... Insulating member, 9... Concave portion.

Claims (1)

[Claims] In a flashlamp device comprising a flashlamp tube surrounded by a reflective member having one side open, the flash light emitted by the flashlamp tube is reflected on a wall portion of the flashlamp tube opposite to the open side. A flash lamp device characterized by being provided with a reflective layer.