JPS60107668A - Fixing device - Google Patents

Abstract

PURPOSE:To prevent the generation of a crease even if a recording paper whose front end is curled is introduced, by introducing the recording paper to a roll fuser part while attarcting the recording paper with a guide member provided near a fixing nip area and an attracting device of a belt conveyor. CONSTITUTION:A belt 18 of a belt conveyor 19 is provided plural holes 18a, and a pipe roll 16 is provided with long holes 16a and round holes 16b corresponding to holes 18a. A bias voltage is applied to a guide plate 14 from a power source 15 to generate an electric field. A sent recording paper 1 is attracted to the belt conveyor 19 by a fan 23 and is attracted by the guide plate 14, and therefore, the front end of the paper 1 is straightened even if this front end is curled, and the paper 1 is introduced to a roll fuser part 11 between a heat roll 9 and a pressure roll 10, and the center part and corner parts of the front end of the paper are taken into a fixing nip area 12 simultaneously. Consequently, a crease is not generated even if the recording paper 1 whose front end is curled is sent.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fixing device for fixing images formed with toner, and particularly to a fixing device that prevents wrinkles caused on recording paper during the fixing. 13.

[Prior art]

A conventional fixing device for fixing a toner image formed on a recording sheet is shown in FIG. In this device, a recording paper 1 on which a toner image has been formed is transferred to a belt roll 2,
3 and a belt 4 through a receiving plate 6 and upper and lower guide plates 7°8, and introduced into a roll tour AJ1 consisting of a heating roller 9 and a pressure roller 1°,
The toner image is fixed by heating and pressing the recording paper I on which the toner image is formed.

By the way, when the recording paper 1 on which the above-mentioned toner image is formed is introduced into the roll fuser section 11 consisting of the heating roller 9 and the pressure roller 1o, if the leading edge of the recording paper 1 is curled, the center of the recording paper 1 will first curl. The fixing area (
After being taken in (hereinafter referred to as the fixing nip area) 121ζ, several portions are taken into the fixing nip area 12 with a slight delay. For this reason, the recording paper 1 is heated and pressurized in the roll user section 11 with the center portion being stretched, and as a result, as shown in FIG. A large number of wrinkles 13 occur on the recording paper 1 after passing through the paper 12 .

OBJECTS OF THE INVENTION The present invention has been made in view of the above-mentioned points, and an object of the present invention is to provide a fixing device that prevents wrinkles from forming on the recording paper even when recording paper with a curled leading edge is introduced. purpose.

[Structure of the invention]

The present invention utilizes the phenomenon that recording paper is generally positively or negatively charged and is attracted by a guide member to which an appropriate bias voltage is applied.

That is, the present invention provides a fixing system in which a recording sheet, on which a predetermined image is formed on a roll user section consisting of a heating roll and a pressure roll, and which is positively or negatively charged, is introduced via a belt conveyor, and the image is fixed. In the apparatus, a guide member to which a predetermined bias voltage is applied is provided near the fixing nip area of the roll user section, and a suction device for suctioning the recording paper conveyed to the belt conveyor is provided. The recording paper is sucked by both of them, thereby preventing wrinkles from forming on the recording paper after the fixing process.

(Embodiments) Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 3 shows an embodiment of the fixing device of the present invention. The apparatus of this embodiment is provided with a bias application guide plate 14 in place of the receiving plate 6 and guide plate 7 of the conventional fixing device shown in FIG. It is constructed using a belt conveyor 19 provided with a belt conveyor (as shown in the figure). In FIG. 2, parts that operate in the same way as those shown in FIG. 1 are given the same reference numerals to simplify the explanation.

In FIG. 3, the bias application guide plate 14 is connected to the power source 15.
A predetermined bias voltage is applied by this, and a predetermined electric field is generated between the bias guide plate 14 and the grounded noid plate 8 to attract the recording paper 1 toward the bias application guide plate 14. . The polarity of the bias voltage applied to the guide plate 7 by the power source 14 is determined by the charging polarity of the recording paper 1 used (determined by the format of the toner image on the recording paper 1).

In this embodiment, the recording paper 1 is assumed to be negatively charged, and a positive voltage is applied to the guide plate 7.

As shown in detail in FIG. 4, the belt conveyor 19 equipped with a suction device has a suction section consisting of a valve 22 and a fan 23 at one end, and a suction pipe roll 16 that is supported by bearings 20 and 21. , a belt roll 17 having a drive 26 at one end and supported by bearings 24.25.
A plurality of belts 18 having a plurality of holes 18a between them.
It is constructed by installing The suction pipe roll 16 is the fifth
One end is closed as shown in the figure, and the side of the heald 1
A long hole], 6a is drilled at a location corresponding to the hole 18a of the belt 18, and a round hole 16b is drilled in a portion between the stretched portions of the belt 18. The reason why the hole 16a corresponding to the hole 18a of the belt 18 is made into a long hole is that the hole t of the belt 18 is
This is to ensure suction via Sa.

When the recording paper 1 is introduced onto the belt conveyor 19 in such a configuration, when the leading edge of the recording paper 1 reaches the position where the suction via 15 of the belt conveyor 19 is arranged, the valve 22 is turned on. Due to the suction action of the fan 23, the recording paper 1 is moved to the suction pipe roll 16.
The recording paper 1 is attracted to the belt conveyor 19 through the hole 18a of the belt 18, the hole 18a of the belt 18, and the hole 18b of the suction pipe roll 16, and then the recording paper 1 is electrostatically attracted to the bias application guide plate 15. become.

As a result, the recording paper 1 is in a state where there is no curl at the leading edge.
1, the leading edge of the recording paper 1 reaches the fixing nip area 12 of the roll user section 11 at the same time, both at the center and at the corners.

That is, even if recording paper with a curled leading edge is fed, this curl is corrected by the suction device of the belt conveyor 19 and the suction action of the guide plate 14 and introduced into the fixing nimp area 12, so that the recording paper is This means that no wrinkles will occur.

(Effects of the Invention) As explained above, according to the present invention, the recording paper is guided to the roll user in a straightened state, so even if the recording paper is introduced in a curled state, there is a difference in the time it takes for the recording paper to be drawn into the fixing nip area. No wrinkles will occur.

[Brief explanation of the drawing]

FIG. 1 is a side view showing a conventional fixing device, FIG. 2 is a plan view showing wrinkled recording paper, FIG. 3 is a side view showing an embodiment of the fixing device of the present invention, and FIG. 4 is a side view showing a conventional fixing device. A plan view showing details of the belt conveyor in the embodiment shown in FIG.
This figure is a perspective view showing details of the suction pipe roll shown in FIG. 4. 1...recording paper, 2, 3.belt roll, 4.belt, 5..belt conveyor, 6. receiving M, 7, 8..guide plate, 9..heating roll, 10.pressure roll, 11.
・Roll Tsuyu-'f'! /12... fixed Ninov area,
13...Wrinkle, 14...Bias application guide plate, 1
5... Power supply, 16... Pipe roll for suction, 17... To belt roll 18... Belt, 19... Belt conveyor with suction device, 20, 21, 24. 25 - Bearing, 22...
・Valve, 23...Fan, 26...Driver. 5 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] A recording sheet on which a predetermined image has been formed is introduced into a roll fuser unit consisting of a heating roll and a pressure roll via a belt conveyor, and in a fixing device that performs a fixing process for the image, a sheet of paper is placed near the fixing nip area of the roll fuser unit. A guide member to which a predetermined bias voltage is applied is provided, and a suction device is provided for sucking the recording paper conveyed to the belt conveyor. A fixing device characterized in that the fixing device is guided to the part.