JP2659728B2 - Electronic copier - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to an electronic copying machine, and more particularly to a curl removal of a copy sheet in a copy machine that performs double-sided copying and superimposed copying of copy sheets. The present invention relates to an electronic copying machine having a curl correction device.

(Prior Art) When performing double-sided copying or superimposing copying on a copy sheet in an electronic copying machine, the copy sheet copied on one side in a photosensitive drum portion is once carried into a loading section in the copying machine, and is further exposed from the loading section. Paper is fed to the body drum and copying is performed.

An ADD supply unit of an automatic duplexer (hereinafter referred to as ADD) for transporting the copy sheet to the stacking unit is provided between the photosensitive drum unit and the stacking unit of the electronic copying machine. The copy paper insertion side of the ADD supply unit discharges the copy paper outside the electronic copier or
A switching guide for switching the transport to the ADD supply unit is provided.

(Problems to be Solved by the Invention) The copy paper discharged from the photosensitive drum portion is in a heat-sensitive state, easily curls, and when the copy paper is guided to the ADD supply unit by the switching guide. Thus, the copy sheet is curved and curled. When the curled copy paper is loaded into the loading section, the copy paper already loaded on the loading section is in a curled state and the next copy paper is difficult to be loaded into the loading section, and the copy paper is loaded from the loading section. There is a problem that it is difficult to smoothly feed the paper to the photosensitive drum portion.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-described problem by providing a curl correction device including a plurality of curl correction rollers capable of effectively performing curl of a copy sheet at an appropriate position between a photosensitive drum unit and a stacking unit. To provide a copying machine.

[Structure of the Invention] (Means for Solving the Problems) An electronic copying machine according to the present invention comprises:
An image forming unit that transfers a developer image formed on an image carrier onto a sheet conveyed by the conveying unit to form an image on the sheet; and a developer image that is transferred by the image forming unit. A fixing unit for fixing the sheet on the sheet, a re-conveying unit having a loop-shaped path for conveying the sheet on which the image is fixed by the fixing unit to the image forming unit, and a loop-shaped path of the re-conveying unit. Provided in the middle, so that the leading end of the sheet in the conveying direction is positioned above the trailing end of the sheet in the direction of gravity so that the rear end of the sheet to be conveyed is aligned in the conveying direction of the sheet. A sheet stacking means inclined to stack the sheets, and a part of the re-conveying means, which is provided downstream in the conveying direction with respect to the fixing means and upstream in the conveying direction with respect to the sheet collecting means; And one b And a pair of curl correction rollers for correcting the curl of the sheet conveyed from the fixing unit and conveying the sheet to the sheet stacking unit after correcting the curl of the sheet conveyed from the fixing unit. Features.

(Effect) In the electronic copying machine of the present invention, there is provided a temporary accumulating section for temporarily accumulating the sheet on which the one-sided image has been formed and aligning the rear end in the sheet conveying direction. Since the curl of the paper is corrected immediately before the paper is stacked on the stacking unit, the curled paper is not stacked in the temporary stacking unit, and the trailing edge of the paper can be reliably aligned. That is, when paper is re-fed from the temporary stacking section, the paper can be reliably fed.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a front view of an electronic copying machine showing one embodiment of the present invention. In FIG. 1, an electronic copying machine 1 has an automatic two-sided copying machine (ADD) having the functions of double-sided copying of a copy sheet 2 and superimposed copying. The copy paper 2 is conveyed to the photosensitive drum unit 4 by the registration roller 3, and
The toner image formed on the peripheral surface of the photosensitive drum 5 is transferred. The toner image is fixed on the copy paper 2 after the transfer of the toner image by the fixing device 6, and the copy paper 2 is discharged outside the machine by the ADD discharge roller 7 or is conveyed to the ADD supply unit 8. Reference numeral 9 denotes a switching guide for switching the conveyance of the copy sheet 2 to the external discharge unit and the ADD supply unit 8.

The ADD supply unit 8 includes a pair of guide plates 11, paper discharge rollers 12 and 13 provided at appropriate positions, and a curl correction device 14 described later. The copy sheet 2 conveyed from the ADD supply unit 8 is carried into the stacking unit 15. The stacking section 15 is arranged such that the sheet feeding side (the right side in FIG. 1) is located upward.

The stacking unit 15 has a lifter 16 described later for a length guide for moving the copy paper 2 to the paper feed side end at the rear end, and a width for adjusting the position of the width of the copy paper 2 in the middle part. A side aligning device 18 is provided for aligning the width of the copy sheet 2 by bringing the guide plate 17 and the copy sheet 2 into contact with the width guide plate 17. Furthermore, at the top of the loading section 15,
For re-feeding the copy paper 2 carried into the stacking unit 15
An ADD pickup roller 19 is provided.

In front of the ADD pickup roller 19, an ADD paper feed roller 21 and an overlap / double-side switching gate 22 are provided. When performing overlay copying on copy paper 2,
The copy sheet 2 is directly guided to the photosensitive drum unit 4 by the overlap / double-side switching gate 22. And copy paper 2
When performing double-sided copying, the copy paper 2 is guided by the switchback unit 23 by the overlap / double-side switching gate 22 and is switched back and forth, that is, the copy paper 2 is switched over to the photosensitive drum unit 4. Paper is fed.

FIG. 2 shows the lifter 16 of the loading section 15 and its driving section. A pair of holding plates 31 for holding a rear portion of the supplied copy sheet 2 are provided at an appropriate interval at a rear portion of the stacking portion 15. The lifter 16 is disposed between the holding plates 31, and its base is located at a rear portion 32 of the rack plate 32.
It is attached to a.

A pinion 34 integral with a pulley 33 meshes with a rack 32b formed on one side of the rack plate 32. Pulley 33
Is connected to a pulley 37 of a motor 36 provided on the fixing member 35. When the motor 36 rotates forward in the direction indicated by the arrow 38, the lifter 16 provided on the rack plate 32 moves in the direction indicated by the arrow 39, that is, to the paper feed side end of the stacking unit 15. By this movement, the leading end of the copy sheet 2 carried into the stacking unit 15 is set to a position where refeeding is possible.

FIG. 3 shows a control circuit for adjusting the position of the copy sheet 2. When the size of the copy paper 2 or the cassette size used in the electronic copying machine is detected by the detection means 41, the control means 42 is operated by the detection signal to control the motor drive circuit.
By operating the motor 43, the motor 36 for adjusting the position in the length direction of the copy sheet 2 is driven. By the rotation of the motor 36 in the forward and reverse directions, the lifter 16 moves in the direction of the arrow 39 or in the opposite direction to set the leading end of the copy sheet 2 at a predetermined position on the sheet feed side end.

A drive circuit 44 for adjusting the width direction of the copy sheet 2 is operated by a signal corresponding to the size of the copy sheet 2 from the control means 42 to drive a width guide motor 45 described later. Has become. The signal input to the control means 42 can be input by operating the operation unit of the control panel 46 shown by a dashed line, in addition to the detection signal by the detection means 41. Can also be set.

FIG. 4 shows a side aligning device 18 for adjusting the width direction of the copy sheet 2 carried into the stacking section 15. The width guide member 51 includes a guide plate 52 with which the side edge of the copy sheet 2 is in contact, and a bottom plate 53 integral with the guide plate 52. A rack plate 54 having a rack 54a on one side is fixed to the lower surface of the bottom plate 53. A pulley 55 integral with the pinion meshing with the rack 54a is connected to a pulley 56 of the guide motor 45 shown in FIG.

In FIG. 5, a support member is provided on the frame of the loading portion 15.
61 is fixed. A base of a pair of swing members 63 each having a free end to which a side aligning roller 62 is pivotally attached is pivotally attached to the support member 61 by a shaft 64. The swing member 63 has a direction in which the side aligning roller 62 descends,
That is, the copy sheet 2 in the stacking section 15 is urged in a direction to be pressed by the side aligning roller 62, and swings around the shaft 64 by a drive mechanism (not shown).

When the side aligning roller 62 comes into contact with the copy sheet 2 due to the lowering of the swinging member 63, the side aligning roller 62 is in the direction of arrow 65, that is, one side edge of the copy sheet 2 carried into the stacking unit 15 (the left side edge in FIG. 5). Is brought into contact with the side wall 52a of the guide plate 52 to perform an operation of aligning the axial direction of the copy sheet 2. The side aligning operation of the side aligning roller 62 is performed by lowering and rotating on the copy sheet 2 every time the copy sheet 2 is carried into the stacking section 15.

The copy paper 2 carried into the stacking section 15 has a lengthwise direction as described with reference to FIGS.
Is adjusted by The width direction is adjusted by the drive circuit 44 driving the width guide motor 45 in response to the size of the copy sheet 2 to move the width guide member 51 forward or backward in the direction of arrow 67 in FIG. You. The copy paper 2 carried into the stacking section 15 in this state is abutted against the guide plate 52 of the width guide member 51 by the side aligning roller 62 as described above, and the width direction is adjusted.

The width guide member 51 and the side aligning roller 62 for adjusting the position of the copy sheet 2 in the width direction are provided only on one side (the left side in the embodiment) of the stacking section 15.

In FIG. 1, when the copy paper 2 is subjected to double-sided copying or superimposed copying, the transport direction of the copy paper 2 is switched by the switching guide 9 as described above, and the copy paper 2 is transported from the photosensitive drum unit 4 into the ADD supply unit 8. Have been.
The copy sheet 2 conveyed from the photosensitive drum unit 4 is heated by the fixing device 6 and is easily curled. The copy paper 2 is curved by the switching guide 9 and the like.
When the copy sheet 2 is conveyed into the ADD supply section 8, the leading end of the copy sheet 2 is curled in a counterclockwise direction in FIG. The curled copy sheet 2 is difficult to carry into the stacking unit 15 and may cause a feeding error when feeding from the stacking unit 15.

The curl correcting device 14 shown in FIGS. 6 and 7 corrects the above-described curled copy sheet 2.

The curl correction device 14 includes a single long curl correction roller 71 pivotally attached to the frame of the ADD supply unit 8, a plurality of short-cut curl correction rollers 72 respectively pressed against the curl correction roller 71, It consists of 73.

As shown in FIG. 7, shafts 74 and 75 to which the curl correction rollers 72 and 73 are fixed are connected to a frame 78 via bearings 76 and 77.
It is pivoted to and unitized. As shown in FIG. 7, the curl correction rollers 72 and 73 have their outer peripheral portions overlapped with each other, and the outer diameter thereof can be set sufficiently large even in a small space. The curl correction rollers 72 and 73 are arranged alternately in the axial direction, that is, in the directions of the shafts 74 and 75 so as to form a zigzag shape.

Two of the three rollers constituting the curl correction device 14 are unitized, that is, the curl correction rollers 72 and 73.
Are arranged in a staggered manner as described above, so that the outer diameters of the curl correction rollers 72 and 73 can be set large. Can be performed in a small space by the above-described overlapping action, and the curl correction device 14
Can be reduced in size.

ADD supply unit 8 due to enlargement of curl correction rollers 72 and 73
The curled leading end of the copy sheet 2 conveyed inside can be reliably inserted into the nip between the outer peripheries of the curl correction rollers 71 and 72. The copy sheet 2 is reliably conveyed by the curl correction device 14, and is handled and curled by the peripheral surface of the curl correction roller 71 pressed by the curl correction rollers 72 and 73 during the passage.

The curl correction of the copy sheet 2 by the curl correction device 14 in this manner ensures that the copy sheet 2 is carried into the stacking section 15 in an appropriate state, and that the paper sheet 2 from the stacking section 15 is reliably fed again. Can be.

[Effects of the Invention] As described above, according to the present invention, there is provided a temporary accumulating section for temporarily accumulating sheets on which single-sided image formation has been performed and aligning the rear end in the sheet conveyance direction, and having a single-sided image formed thereon. Since the curl of the paper is corrected immediately before the paper is accumulated in the temporary accumulating portion, the curled paper is not accumulated in the temporary accumulating portion, and the rear end of the paper is reliably aligned. It can be carried out. That is, when re-feeding the paper from the temporary stacking unit, the paper can be reliably fed.

[Brief description of the drawings]

FIG. 1 is a front view showing an example of an electronic copier to which the present invention is applied, FIG. 2 is a perspective view showing a lifter device of the electronic copier, and FIG. 3 is a lifter device and a side aligning device of a loading section. FIG. 4 is a perspective view showing a width guide member and a drive unit of the side aligning device, FIG. 5 is a plan view showing a side aligning roller unit, and FIG. 6 is a block diagram of the present invention. FIG. 7 is a side view showing a curl correction device provided in an ADD supply section of an electronic copying machine according to an embodiment, and FIG. 7 is a perspective view of a unitized curl correction roller constituting the curl correction device. 2. Copy paper 4. Photosensitive drum unit 15. Stacking unit 8. ADD supply unit 9. Switching guide 71. Curling correction rollers 72, 73. Curl correction arranged in a zigzag pattern. roller

Claims (1)

(57) [Claims] 1. A conveying means for conveying a sheet, and an image forming means for transferring a developer image formed on an image carrier onto the sheet conveyed by the conveying means to form an image on the sheet. Fixing means for fixing the developer image transferred by the image forming means onto the sheet, and re-conveying having a loop-shaped path for conveying the sheet on which the image is fixed by the fixing means to the image forming means again Means, provided in the middle of a loop-shaped path of the re-conveying means, so that the leading end of the sheet in the conveying direction of the sheet is aligned with the rear end of the sheet in the conveying direction so that the rear end of the sheet in the conveying direction is aligned. A sheet accumulating unit that is provided to be inclined so as to accumulate the sheets so as to be positioned above the rear end in the direction of gravity; and a part of the re-conveying unit, which is downstream of the fixing unit in the conveying direction. And the paper stacking hand A plurality of rollers are provided in contact with one roller, and a plurality of rollers are in contact with one roller. An electronic copying machine, comprising: a pair of curl correction rollers for conveying.