JPH01270086A - Fixing device using flash lamp - Google Patents

Abstract

PURPOSE:To prevent an excessive toner image from being fixed by dividing suction grooves in the traveling direction of a form and inhibiting the form from being sucked nearby right below the flash lamp. CONSTITUTION:The form 1 is sucked by a belt 2 and carried to the side of a roller 10. The flash lamp 15 emits light at prescribed intervals in synchronism with the conveyance of the form 1 and toner is melted and fixed on the form 1. Air is sucked by an air sucking device through holes 3 of the belt, the suction grooves 5a and 5b which are divided in the form traveling direction in an air chamber 4, and the air chamber 4. Here, when the air chamber 4 divided into two at a prescribed position, the air is not sucked nearby right below the lamp 15. Consequently, particles of toner which are scattered at the time of the light emission of the lamp 15 do not stick on the form again. Thus, an excessive image other than a transferred toner image is prevented from being fixed on the form 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a fixing device using a flash lamp of a printing device or a copying device using an electrophotographic method.

[Background of the invention]

2. Description of the Related Art In a printing device or a copying device using an electrophotographic method, it is known that a flash lamp is used to fix a toner image transferred to a sheet of paper.

In addition, on the surface of the suction groove of the air chamber having the suction groove,
It is also known to convey paper by moving a perforated belt along a suction groove, sucking air through the holes in the belt and the suction groove to attract paper to the belt.

In the fixing device using the flash lamp described above, when the paper is conveyed by the belt conveyance, there are the following problems.

FIG. 3 is a sectional view showing the general structure of a fixing device according to the prior art. In FIG.
Air is attracted to the belt 2 by suction through the suction groove 5 of the air chamber. The belt 2 is wound around a quick-acting shaft 6 and an idler shaft 7, and is moved along the suction groove 5 of the air chamber by rotating the quick-moving shaft 6. At this time, since the paper 1 is attracted to the belt 2, it is sent to the puller 10 by the movement of the belt 2.

Before entering the fixing device, there is a transfer device! i (not shown), an unfixed toner image is transferred to the paper. The flash lamp 15 emits light at a timing that corresponds to the paper feed speed and the light emitting width of the flash lamp in the paper running direction, and the flash lamp 15 melts the toner on the paper by emitting light at the timing when the paper passes under the flash lamp. Let it settle in.

When the flash lamp emits light, fine powder of 1-ner flies up and is sucked onto the paper through the hole drilled in Bell 1, resulting in a transfer in the shape of the hole in the belt, as shown in Figure 4. The extra 1-ner image that was added is fixed onto the paper.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art and to prevent excess toner images other than the transferred toner image from being fixed on paper.

[Summary of the invention]

The present invention focuses on the fact that the flash lamp emits light for a short period of time (less than 1 m S E C) and that the range in which fine toner powder is flying up is limited. It has a structure that eliminates the suction groove in the air chamber.

[Embodiments of the invention]

An embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, a sheet of paper 1 is attracted by a belt 2 and conveyed to a puller 10 side. The flash lamp 15 emits light at a certain emission cycle in synchronization with the timing when the paper 1 is conveyed, and the toner on the paper is melted and fixed on the paper. Air is passed through the hole 3 in the belt, the suction grooves 5a and 5b, and the air chamber 4 divided in the paper running direction in the air chamber to an air suction device (not shown).
is attracted by. The air chamber is divided into two, 5a and 5b, near the area directly below the flash lamp.

It has a structure that does not suck air.

An example of the relationship between the light emission width of the flash lamp and the shape of the suction groove will be explained in detail with reference to FIG. As shown in the figure,
It can be seen that the range in which air is not sucked is not symmetrical with respect to the flash lamp light emission center, but is shifted by a certain value. The amount and direction of the shift depends on the air flow near the paper. In general, if the length of the suction groove is shortened, the paper tends to float up, so in order to ensure stable paper travel, the longer the suction groove is, the better. (The smaller the area where air is not sucked, the better.) From this point of view, the relationship shown in FIG. 2 is important in narrowing the area where air is not sucked.

〔Effect of the invention〕

According to the present invention, the suction grooves in the air chamber are manufactured to prevent the fine powder of 1 to toner that flies up when the flash lamp is emitted from re-adhering to the paper, so that the excess toner image other than the transferred toner image does not stick to the paper. It is possible to prevent it from being fixed.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention, FIG. 2 is an explanatory diagram showing the positional relationship between the light emitting width of the flash lamp and the shape of the suction groove in the case of an embodiment of the present invention, and FIG. 3 4 is a longitudinal sectional view showing an embodiment of the prior art, and FIG. 4 is an explanatory diagram showing the problems of the prior art. In the figure, 1 is paper, 2 is a belt, 3 is a hole in the belt, 4 is an air chamber, 5.5a and 5b are suction grooves of the air chamber, and 15 is a flash lamp. Name of patent applicant Hitachi Koki Co., Ltd. Kaya 10 No. 20 Kaya 30 Figure 4

Claims (1)

[Claims] In a printing device that uses electrophotography, a flash lamp is used to heat and melt the toner, a belt that conveys the paper has holes to suck the paper, and a suction groove that allows air to pass through to make the belt suck the paper. What is claimed is: 1. A fixing device comprising an air chamber with a suction groove divided in the paper running direction, and the paper is not sucked with air in the vicinity directly below a flash lamp.