JPH03249055A - Image forming device - Google Patents

Abstract

PURPOSE:To stably convey sheets of paper and prevent a jam in an image forming device by providing a freely turning roller-shaped member in a position in which it will not disturb attraction of a cut medium, as in the opening of a guide plate. CONSTITUTION:A roller 42 has a pulley portion integrally therewith and an endless belt 51 wound around the pulley portion. When a photosensitive drum 25 is rotated in the direction indicated by the arrow E, the roller 42 is rotated via the belt 51 in the direction indicated by the arrow F at the same peripheral velocity as that of the photosensitive drum 25. During rotation of the roller 42, three holes 45 are constantly opposite to an opening 47. Therefore a peeling roller continuously exerts an attracting force on a cut sheet of paper 28 by means of its negative pressure source 23 and rotation of the roller 42 continuously exerts a conveying force on the paper 28. Hence the paper 28 is surely peeled from the photosensitive drum 25 even when the speed at which the paper 28 is conveyed and that of rotation of the photosensitive drum 25 are higher than usual.

Description

[Detailed Description of the Invention] [Summary] A toner image forming means for forming a toner image on a cut-shaped medium, a fixing means for fixing the toner image on the cut-shaped medium, and a toner image forming means for fixing a toner image on the cut-shaped medium; a conveying means for adsorbing and conveying the cut-shaped medium along a path to the destination;
The purpose of the image forming apparatus is to stably transport cut-shaped media and prevent jams from occurring, and the transport means is an endless-shaped image forming apparatus having a suction hole for sucking the cut-shaped media. a belt, a portion of the guide surface of the cut medium that corresponds to the suction hole is opened, and a guide plate that guides the endless belt; and a guide plate that is provided in the opening and supports the endless belt. and a rotatable roller-like member.

[Industrial application field]

The present invention provides a toner image forming means for forming a toner image on a cut-shaped medium, a fixing means for fixing the toner image on the cut-shaped medium, and a toner image forming means for fixing the toner image on the cut-shaped medium, and a fixing means for fixing the toner image on the cut-shaped medium. The present invention relates to an image forming apparatus including a conveying means that attracts and conveys a cut-shaped medium.

[Conventional technology]

In an image forming apparatus such as an electrophotographic printer, it is necessary to perform fixing after forming a toner image on a cuff-shaped medium.

The toner image on the cut-shaped medium is only attached by electrostatic force until it is fixed, so the cut-shaped medium is supported from the back side and transferred from the toner image forming section to the fixing section. transported.

At this time, it is necessary to not only support the cut-shaped medium but also to actively transport it, so the cut-shaped medium is suction-supported through an endless bed having suction holes. The endless belt is guided by a guide plate having an opening in a portion corresponding to the suction hole.

[Problem to be solved by the invention]

However, when using such a conventional image forming apparatus, there is a problem in that slippage occurs between the endless belt and the drive shaft, and the cut medium is not stably conveyed, resulting in jamming.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, an object of the present invention is to provide an image forming apparatus that can stably convey a cut-shaped medium and that does not cause jams.

[Means to solve the problem]

The purpose is to provide a toner image forming means for forming a toner image on a cut-shaped medium, a fixing means for fixing the toner image on the cut-shaped medium, and a curved toner image forming means extending from the toner image forming means to the fixing means. an image forming apparatus comprising: a conveyance means for suctioning and conveying the cut medium along a path, the conveyance means comprising: an endless belt having a suction hole for suctioning the cut medium; A portion corresponding to the suction hole on the guide surface side of the cut medium is opened, and a guide plate that guides the endless belt, and a rotatable guide plate that is provided in the opening and supports the endless belt. This is achieved by an image forming device comprising a roller-like member.

Since it is provided in a position that does not interfere with the suction of the media, the cut media can be transported.

〔Example〕

Embodiments of an image forming apparatus according to the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing an embodiment of an image forming apparatus according to the present invention;
FIG. 2 is a diagram showing the overall configuration of an image forming apparatus according to the present invention;
FIG. 3 is a plan view of the paper transport section, and FIG. 4 is a partially sectional view.

In the figure, 100 is a photosensitive drum, and around it,
Fur brush cleaner 101. Front charger 102, LED
Exposure device 103a using an array.

103b, two-component magnetic brush developer 104. A transfer charger 105 and the like, which are integrally provided with an AC static eliminator, are provided.

The photosensitive drum 100 is rotated in the direction of an arrow 106, uniformly charged by a pre-charger 102, and an electrostatic latent image is first formed in an exposure device 103. Next, this electrostatic latent image is developed by the developing device 104 to form a toner image. Further, sheet paper 107, which is a cut-shaped medium, is supplied from a paper feed section (not shown) in the direction of arrow 108, and transferred to transfer charger 109.
The toner image is transferred.

Thereafter, the sheet paper 107 is removed by a peeling roller 110.
The sheet is peeled off from the photosensitive drum 100 and transferred to the sheet conveying device 11.
1, the image is conveyed in the direction of arrow 113 under a flash fixing device 112 using flash lamps 112a to 112b, and in this process, it is flash-fixed.

The 2d sheet paper 107 on which the toner image has been fixed is discharged to a stacker (not shown) by a conveyance roller 114aDl14b.

Moreover, as shown in FIGS. 1 to 3, a peeling roller 1
Sheet paper 1 separated from photosensitive drum 100 by 10
07 is conveyed to the fixing unit 112 along a curved conveyance path by the paper conveyance device 41.

By curving the conveyance path in this manner, light from the flash lamps 112a to 112d leaking from the fixing section 112 is prevented from being irradiated onto the photosensitive drum 100.

This peeling roller 110 is configured as follows. That is, in the figure, 42 is a roller,
It is rotatably supported by the hollow member 43 by a bearing (not shown).

A plurality of holes are arranged in two rows in a staggered manner over the entire circumference of the roller 42. 45-1 is a first row of holes, which includes holes 45-1-1 to 451-1-N.

45-2 is a hole group in the second row, and holes 45-2-1 to 45
-2-N.

Holes 45-1-1 to 451-1-N and 45-2-1 to 45
-2-N is a staggered arrangement.

When a predetermined hole is not specified, it is indicated by reference numeral 45.

A sleeve 46 is fitted and fixed in the hollow member 43.

An opening 47 is formed in the hollow member 43 and the sleeve 46 so as to face the paper peeling portion 26 on the circumferential surface of the photosensitive drum 25 .

The size of the opening 47, the size of each hole 45, and the pitch of the holes 45 are determined so that three to four holes 45 are always facing the opening 47.

The end side of the hollow member 43 communicates with a negative pressure source (not shown).

The roller 42 integrally has a pulley portion 42a, and an endless belt 51 is wound around the pulley portion 42a.

When the photosensitive drum 25 is rotated in the direction of arrow E, the roller 42 is rotated in the direction of arrow F at the same circumferential speed as the circumferential speed of the photosensitive drum 25 via the belt 51.

During rotation of the roller 42, the three holes 45 always face the openings 47.

Therefore, in the peeling roller 110, the negative pressure source 23 causes the suction force to continuously act on the cut sheet-like paper 28, and the rotation of the roller 42 causes the conveying force to continuously act on the paper 28.

Therefore, even if the transport speed of the paper 28 and the rotational speed of the photosensitive drum 25 are higher than those in the past, the paper 28 can be reliably separated from the photosensitive drum 25.

In addition, since the holes 45 are arranged in two rows in a staggered manner, the size of the opening facing the three holes is small compared to the case where the holes are arranged in a single row. It acts concentratedly on the peeling portion 26, and the paper 28 is peeled off more reliably.

A plurality of peeling rollers 110 having the above configuration are arranged at equal intervals in the axial direction of the photosensitive drum 40, and the paper 28 is sucked at a plurality of locations in the width direction of the paper 28, and is reliably exposed to light over its entire width. It is peeled off from the drum 25.

The paper conveyance device 41 includes a pulley section 42a and rollers 52.5.
The belt 51 wound around the belt 3 has a perforated structure having suction holes 40 (only the negative part is shown), and a plurality of guide rollers 55 are provided to guide the belt 51. This is a configuration in which the negative pressure source 23 is communicated with the negative pressure source 23.

The belt 51 runs in the direction of arrow 1 at the same speed as the circumferential speed of the roller 22, and exerts a suction force in the section where it runs on the guide plate 59.

As a result, the paper 2 peeled off by the paper peeling device 40
8 is quickly attracted to the belt 51 and conveyed in the direction of the arrow ■.

A suction force from the negative pressure source 23 acts on the belt 51, and the belt 51 is pressed against the guide plate 59 and the guide roller 55 as shown in FIG. 4, and runs with a relatively light load.

As shown in FIG. 3, a plurality of paper conveying devices 41 are provided in the axial direction of the photosensitive drum 25, disposed between adjacent peeling rollers 110, so that the paper 28 can be conveyed smoothly and reliably after being peeled off. It will be done.

That is, as shown in FIG. 4, the outer ring 55a is opposed to the inner ring 55n fixed to the fixed shaft 55X.

55b is rotatably provided, and the outer ring 55a.

55b projects above the guide plate 59 by a height h (approximately l).

This makes it possible to bring the endless belt 51 and the guide plate 59 into substantially line contact, and also causes rolling friction on the back surface of the endless belt 51. Therefore, the frictional load applied to the endless belt 51 can be significantly reduced, and the drive roller 52 that drives the endless belt 51 does not slip between itself and the endless belt 51. It is also possible to prevent the motor from stepping out.

Furthermore, in this embodiment, the guide plate 59 with the opening 54 forms a suction box 60 and is connected to the negative pressure source 23 .

By the way, if a strong paper such as A3/135 kg paper is used as the cut sheet 28, the roller 52
The paper may separate from the belt 51 at the side.

Therefore, the negative pressure of the negative pressure source 23 is increased (then the paper 28
When the opening 40 of the bell 51 is completely covered, a strong negative pressure is applied to the suction box 60 to suck air into the suction box 60. As a result, even when paper with strong stiffness is used, paper can be transported stably, and paper having various sizes and thicknesses can be applied.

〔Effect of the invention〕

As described above, according to the two aspects of the present invention, paper can be transported stably and jams do not occur.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a diagram showing an embodiment of the image forming apparatus according to the present invention, FIG. 2 is a diagram showing the overall configuration of the image forming apparatus according to the present invention, and FIG. 3 is a diagram showing paper conveyance. FIG. 4 is a partially sectional view. In the figure, 25 and 100 are photosensitive drums, 41 is a paper conveyance device, 51 is an endless belt, 54 is an opening, 55 is a guide roller, and 59 is a guide plate.

Claims (1)

[Claims] a toner image forming means for forming a toner image on the cut medium; a fixing means for fixing the toner image on the cut medium; and a toner image forming means for fixing the toner image on the cut medium; An image forming apparatus comprising: a conveying means for suctioning and conveying the cut medium, the conveying means having an endless belt having suction holes for suctioning the cut medium; A portion corresponding to the hole is opened, and includes a guide plate that guides the endless belt, and a rotatable roller-like member that is provided in the opening and supports the endless belt. Image forming device.