JPH0618376Y2 - Heat and pressure fixing device for electronic copiers - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a heat and pressure fixing device for an electronic copying machine.

[Conventional technology]

FIG. 6 shows a general conventional example, which comprises a fixing roll device c composed of a heating roll a and a pressure contact roll b, and a pair of conveying rolls d and e. The pressure-fixed sheet f passes the transport rolls d and e and is discharged to the sheet tray g.

In the fixing roll device described above, the paper f that has passed through the heating roll a is subjected to heat stress and pressure, as shown in the figure, is bent and deformed toward the heating roll a side, and if it is discharged as it is, it is not properly accommodated in the paper tray g. Alternatively, when the once discharged paper f is tried to be sent again from the paper feed side, a defect in paper feeding due to deformation may occur.

Therefore, in order to solve the above problems in the conventional technology,
As shown in FIG. 7, the passage h between the fixing roll device c and the transport rolls d and e is curved in the direction opposite to the deformation of the paper, and as shown in FIG. It is composed of a book roll, and is configured to be curved and deformed in the opposite direction by passing through the discharge roll device i.

[Problems to be solved by the invention]

However, in the correction method as shown in FIG.
Since the force to be corrected in the passage h is smaller than the heat stress applied by the heating roll a given to the above, the correction effect is small and the correction cannot be completed.

Further, the correction method shown in FIG. 8 has problems that the device becomes complicated and the cost becomes high.

[Means and Actions for Solving Problems]

The present invention has been made in view of the above, and with a simple configuration, therefore, it is possible to correct the curved deformation of the paper at a low cost, and it is possible to prevent the accommodation deterioration due to the paper deformation and the paper running failure during double-sided copying and single-sided multiplex copying. An object of the present invention is to provide a heat and pressure fixing device for an electronic copying machine capable of preventing such a problem. The structure is such that a fixing roll device 1 including a heating roll 2 and a pressure contact roll 3 to a pair of rolls 4a and 4b.
At least both side edges in the width direction of the sheet 9 that has passed through the fixing roll device 1,
A pressing plate 6 having elasticity that presses the fixing roll device 1 from the tangent line in the feeding direction from the fixing roll device 1 to the pressure contact roll 3 side of the fixing roll device 1, and heating of the fixing roll device 1 from the tangent line in the feeding direction over the entire width of the paper sheet 9. A pressing plate 7 having elasticity for pressing to the roll 2 side is provided in this order from the upstream side of the above-mentioned transport path and toward the downstream side in the feeding direction at an acute angle with respect to the tangent line in the feeding direction. When passing through the fixing roll device, the sheet curved and deformed into a shape along the heating roll is corrected by the holding plate while being guided to the transport roll.

〔Example〕

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

In the figure, 1 is a fixing roll device comprising a heating roll 2 and a pressure contact roll 3 which is in pressure contact with the heating roll 2, 4 is a pair of rolls 4a,
The transport rolls 4b and 5 are discharge trays located on the downstream side of the transport rolls 4.

An upper holding plate 6 and a lower holding plate 7 are provided in the conveying path extending from the fixing roll device 1 to the conveying roll 4 with the upper holding plate 6 positioned upstream in the conveying direction. Both of the pressing plates 6 and 7 are oriented in the sheet conveying direction, and the leading end portions of the pressing plates are slightly harder than the conveying tangent line.
It is arranged at an acute angle with respect to the tangent to the feed direction. Further, both pressing plates 6 and 7 are made of elastic plate materials. Each of the pressing plates 6 and 7 has a shape as shown in FIG. 2, and the upper pressing plate 6 has a plurality of tongue pieces 6a and 6a for pressing only both end portions of a sheet of each size to be conveyed from the upper side. , 6a, and the lower holding plate 7 is shaped so as to come into contact with the entire width of the sheet from below. Note that FIG. 2 shows an example in which three tongue pieces 6a, 6b, 6c are provided, but this is provided according to the size of the paper. The part is pressed by, for example, the tongue piece 6a on one side and the tongue piece 6b on the middle part, and in the case of a large width sheet, both ends thereof are pressed by the tongue pieces 6a, 6c on both sides. Then, at this time, the intermediate portion of the large-width sheet is also pressed by the tongue piece 6b of the intermediate portion.

In the above-mentioned structure, the paper on which the toner image has been transferred by the transfer device (not shown) is sent by the transport to the fixing roll device 1 shown in FIG. 1, where the toner image is fixed on the paper by heat and pressure. . After that, the peeling claw 8 separates the heating roll 2, guides it to the conveyance path, and feeds it to the conveyance roll 4. Since the feeding speed of the transport roll 4 is slightly higher than that of the fixing roll device 1, the sheet is fed along the tangent of both rolls when the fixing roll device 1 and the transport roll 4 regulate the sheet. .

At this time, since the upper and lower pressing plates 6 and 7 are slightly depressed vertically with respect to the tangent line of the sheet in the feeding direction, stress is applied to the sheet.

That is, as shown in FIG. 3, when the sheet 9 passes through the fixing roll device 1, the sheet 9 is bent upward in the front-rear direction (X, X direction) with respect to the transport direction, and the intermediate portion is deformed to be concave. However, the pressing plate 7 on the lower side applies a force in the opposite direction to correct the bending in the X and X directions.

Further, the upper holding plate 6 abuts at least both ends of the paper 9 to deform this portion downward, and as a result, as shown in FIGS.
It is modified as shown.

The deformation of the sheet 9 by the upper and lower pressing plates 6 and 7 serves as an inhibiting force against the deformation of one side against the deformation of the other side. As a result, the deformation of the sheet 9 is reduced, and the storability and sheet transportability are improved. Is stable.

Further, the paper 9 conveyed from the fixing roll device 1 to the conveyance roll 4 is conveyed in a zigzag shape in the vertical direction with respect to the tangential line in the conveyance direction, and moreover, the presser for pressing the both widthwise end portions of the paper 9 downward. Since the plate 6 is located on the upstream side of the conveyance path, both ends of the sheet 9 are deformed by the pressing plate 6 while the temperature has just passed through the fixing roll device 1 and is still high. , The rigidity of the paper is relatively stronger than the other parts, and the deformation of both end portions is corrected well.

At this time, the two pressing plates 6 and 7 are directed to the downstream side at an acute angle with respect to the tangent line in the feeding direction, so that the sheet 9 is smoothly conveyed in a zigzag manner.

[Effect of device]

According to the present invention, it is possible to correct the curved deformation of the paper with a simple structure and at a low cost, and it is possible to prevent the storage failure due to the paper deformation, the paper feeding failure at the time of double-sided copying and single-sided multiplex copying, and in particular. According to the present invention, it is possible to satisfactorily correct the deformation of both end portions in the width direction of the sheet 9 which is stronger than the other parts, and the sheet 9 exiting the fixing roll device 1 is smooth while the above-described deformation correction is performed. Be transported to.

[Brief description of drawings]

1 to 5 show an embodiment of the present invention.
The figure is a vertical side view, FIG. 2 is a perspective view of a main portion, FIG. 3 is a perspective view showing a state of a sheet when it exits the fixing roll device, and FIG.
The figure is a perspective view showing the sheet after correction, and FIG. 5 is the V- of FIG.
A sectional view taken along the line V and each of FIG. 6 to FIG. 8 are vertical side views showing a conventional example. 1 is a fixing roll device, 2 is a heating roll, 4 is a transport roll, 6 and 7 are holding plates, and 9 is paper.

Claims (1)

[Scope of utility model registration request] 1. A sheet 9 that has passed through the fixing roll device 1 is provided on a conveyance path from a fixing roll device 1 including a heating roll 2 and a pressure contact roll 3 to a conveying roll 4 including a pair of rolls 4a and 4b, at least on both sides in the width direction. A pressing plate 6 having elasticity to press the end portion from the tangent line in the feeding direction from the fixing roll device 1 to the conveying roll 4 toward the pressure contact roll 3 side of the fixing roll device 1 and the fixing roll 6 from the tangent line in the feed direction over the entire width of the paper sheet 9. A pressing plate 7 having elasticity for pressing to the heating roll 2 side of the device 1 is provided in order from the upstream side of the above-mentioned conveying path and toward the downstream side in the feeding direction so as to form an acute angle with respect to the tangent line in the feeding direction. A heat and pressure fixing device for electronic copying machines.