JP2002338072A - Paper feeding device of image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify check of the state of a roller for drawing a recoding paper from a containing tray and feeding it and replacement of the roller. SOLUTION: As an inspection window is formed on a rotation supporting plate 626 on a separation feeding unit 611, the state of a pickup roller 621 can be easily checked through the inspection window. As the rotation supporting plate 626 is rotatably supported on the upper edge of a paper containing tray 610, check of the state of a lower face of the rotation supporting plate 626 and its maintenance can be done easily by rotating and moving the rotation supporting plate 626 upward.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding device of an image forming apparatus which is mounted on an image forming apparatus such as a copying machine, a printer, a facsimile machine, etc., and stores and supplies recording paper.

[0002]

2. Description of the Related Art As is well known, in this type of paper feeder, a large number of recording papers are stacked and stored in a storage tray. It is transported and supplied to the forming apparatus. In order to pull out and transport the recording paper from the storage tray, a roller that is pressed against the recording paper in the storage tray and pulls out the recording paper, and a roller that separates and transports the pulled out recording paper one by one, etc. Provided. These rollers generate large friction with the recording paper, and are contaminated or abraded by, for example, SiO ₂ contained in the recording paper, and the force of the rollers for transporting the recording paper is reduced. Therefore, each roller needs to be replaced. In addition, in order to reliably pull out and convey the recording paper, the mounting accuracy of each roller must be high, and it is necessary to maintain the mounting accuracy even if each roller is replaced.

For example, in the apparatus described in Japanese Patent Application Laid-Open No. 11-334904, the developing unit and the fixing unit are separated from each other by opening the side wall of the apparatus main body, and the state of a sheet feeding roller below these units is changed. Check and then replace the feed roller. Further, a structure in which the paper feed roller can be attached to and detached from the drive shaft by a simple operation is adopted.

[0004]

However, in the apparatus disclosed in the above publication, since the paper feed roller is built in the apparatus main body, the state of the paper feed roller is checked unless the developing unit and the fixing unit are separated. I couldn't do that.
It is extremely difficult for the user to perform such work regularly. Therefore, instead of relying on checking the state of the paper feed rollers, when paper jams frequently occur in the paper feeder, it is determined that it is time to replace the paper feed rollers, and the paper feed rollers are replaced. It was a reality. In addition, since the paper feed roller is replaced after the developing unit and the fixing unit are detached, this work is burdensome for the user.

In view of the above, the present invention has been made in view of the above-mentioned conventional problems, and an image forming apparatus capable of easily confirming and replacing the state of a roller for pulling out or transporting recording paper from a storage tray. It is an object of the present invention to provide a paper feeding device.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is directed to an image forming apparatus which forms an image on a recording sheet and feeds the recording sheet while accommodating the recording sheet. The apparatus includes a storage tray that stores a plurality of sheets in a stacked state, and a roller group that pulls out the recording sheet from the storage tray and conveys the recording sheet to the image forming apparatus, and the roller group is integrally and movably mounted. ing.

According to the present invention having such a configuration, the roller group is integrally and movably mounted. If this roller group is moved, its state can be easily checked and replaced.

Further, in the present invention, a window is provided to look into the roller group.

By providing such a window, the state of the roller group can be checked more easily.

Further, in the present invention, the drive roller of the roller group is passed through the drive shaft, and the rotation of the drive shaft is transmitted to the drive roller by detachable engagement between one end of the drive roller and the drive shaft, thereby driving the drive roller. The detachable engagement between the other end of the roller and the drive shaft limits the movement of the drive roller in the longitudinal direction.

In order to remove the drive roller, the engagement between the other end of the drive roller and the drive shaft is released, and then the drive roller is moved in the longitudinal direction to remove the drive roller from the drive shaft.
To attach the drive roller, the drive roller is passed through the drive shaft, and one end and the other end of the drive roller are engaged with the drive shaft.

Further, in the present invention, the roller group is rotatably supported on the shaft, and approaches and separates from the storage tray by the rotational movement.

[0013] When the roller group is close to the storage tray, the recording paper is pulled out of the storage tray by the roller group and conveyed, and when the roller group is separated from the storage tray, the recording paper is supplied to the storage tray. I do.

[0014]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a side view illustrating an image forming apparatus to which an embodiment of a sheet feeding device according to the present invention is applied. The image forming apparatus 1 shown in FIG. 1 is a multi-function type, and performs functions of a copier, a printing machine, a facsimile machine, and the like. The image forming apparatus 1 includes a printer 2, a scanner 3, an automatic document feeder 4,
And a multi-stage paper feeder 6.

In the automatic document feeder 4, when a document is placed on the document set tray 40, the document is conveyed onto the platen glass 30 and positioned, and after the image of the document is read by the scanner 3, the document is read. Is transported and discharged. In addition, one side of the automatic document feeder 4 is pivotally supported so that a non-transportable document can be placed on the platen glass 30 so that the entire device 4 can be opened and closed.

In the scanner 3, one of an automatic reading mode and a manual operation reading mode can be selected and set. When the former automatic reading mode is selected, the image of the document is read in conjunction with the transfer of the document onto the platen glass 30 by the document feeder 4. When the latter manual operation reading mode is selected, the image of the original placed on the platen glass 30 is read in response to the manual operation. In either mode, the first and second scanning units 31, 32
Are moved while maintaining a predetermined speed relationship with each other, and the first scanning unit 31 exposes the image of the original placed on the platen glass 30 to the first and second scanning units 3.
The light reflected from the document is guided to the lens 33 by the lenses 1 and 32, and the image of the document is converted by the lens 33 into the photoelectric conversion element (C).
(CD) 34. The CCD 34 repeatedly scans and reads the image of the document in the main scanning direction, and outputs image data indicating the image of the document.

The printer 2 receives image data from the scanner 3 and image data from an external device (for example, a personal computer) and records an image represented by the image data on a recording sheet.

The printer control unit 24 functions as an interface for controlling the electrophotographic processing unit 20 and receiving image data from an external device. The image control unit 25 performs predetermined image processing on image data from an external device, or executes the light scanning unit 22 according to the image data.
Drive control.

The electrophotographic process unit 20 includes a photosensitive drum 200, a charging roller 201, an optical scanning unit 22, a developing unit 202, a transfer unit 203, a cleaning unit 204, and a charge removing unit (not shown). The surface of the photosensitive drum 200 is
1 allows for uniform charging. The optical scanning unit 22 forms a light beam modulated according to image data, and repeatedly scans the surface of the photosensitive drum 200 in the main scanning direction with the light beam to form an electrostatic latent image on the surface of the photosensitive drum 200. I do. The developing unit 202 transfers the toner to the photoconductor 200
Supply to the surface. This toner adheres to the electrostatic latent image on the surface of the photoconductor drum 200 to form a toner image. The transfer unit 203 overlaps the recording paper conveyed from below with the photosensitive drum 200 and transfers the toner image from the photosensitive drum 200 to the recording paper.

Above the electrophotographic process section 20, a fixing device 23 is disposed. The fixing device 23 heats and presses the recording sheet to fix the toner image on the recording sheet.

Further, the recording paper is transported by each transport roller 28 and is delivered to the relay path unit 8 of the paper discharge processing device 5.

When an image is to be recorded on the back side of the recording sheet, the conveyance of the recording sheet is temporarily stopped, and the recording sheet is conveyed from the relay path unit 8 to the printer 2 in the reverse direction. In the printer 2, the branch claw 251 is rotated,
Double-sided conveyance path unit 1 feeds recording paper by branching claws 251
Lead to zero. The two-sided conveyance path unit 10 conveys the recording sheet along the two-sided conveyance path 250 and guides the recording sheet to the electrophotographic process 20 again. Thereby, the front and back of the recording paper are reversed, and an image is recorded on the back of the recording paper. The recording paper on which the images are recorded on the front and back sides is conveyed by the conveying rollers 28 and delivered to the relay path unit 8 of the sheet discharging processing device 5.

A paper feed unit 21 is provided below the printer 2. The paper feeding unit 21 separates and takes out the recording paper from the paper storage tray 210 and the paper storage tray 210 one by one.
A separation / supply unit 211 for supplying recording paper to the electrophotographic processing unit 20; The sheet storage tray 210 can be pulled out of the image forming apparatus 1 main body,
In the pulled-out state, the recording paper is supplied to the paper storage tray 210.

Next, the multi-stage paper feeder 6 is optional and is detachable from the image forming apparatus 1. In the multi-stage paper feeding device 6, a plurality of types of recording papers are stored in respective paper storage trays 610. Each separation and supply unit 611 stores the recording paper in the respective paper storage tray 6.
The recording paper is separated from the recording paper 10 and sent out to the electrophotographic processing unit 20. Each of the sheet storage trays 610 can be pulled out from the main body of the multi-stage paper feeder 6, and in the pulled-out state, recording paper is supplied to each of the sheet storage trays 610. Further, the number and size of each sheet storage tray may be changed as appropriate.

The paper discharge processing device 5 includes a relay path unit 8 and a post-processing unit 9. Relay path unit 8
Includes a relay path 84 that receives recording paper from the printer 2 and conveys the recording paper to the post-processing unit 9, a switchback path 83 that once receives the recording paper from the printer 2 and returns the recording paper to the printer 2, A gate plate 81 for guiding recording paper from the printer 2 to one of the relay path 84 and the switchback path 83; The gate plate 81 is swingable, and when its tip is directed downward, the recording paper is guided to the switchback path 83,
When the leading end is directed upward, the recording paper is
It is led to 4.

The relay path 84 is provided with transport rollers 85 that rotate in one direction. The transport rollers 85 guide recording paper to the post-processing unit 9. The switchback path 83 is provided with a mounting plate 86 on which recording paper is mounted. When the recording paper is guided to the switchback path 83, the rear end of the recording paper is sandwiched between the respective transport rollers 28 of the printer 2, and the respective transport rollers 28 are stopped while the recording paper is placed on the mounting plate 86. Then, the conveyance of the recording paper is temporarily stopped. Thereafter, the transport rollers 28 are rotated in the reverse direction to transport the recording paper to the printer 2 in the reverse direction. In the printer 2, as described above, the recording paper is guided to the transport path 250 of the duplex transport path unit 10 by the branch claw 251, and the recording paper is transported again through the transport path 250 to the electrophotographic process 20, where the recording paper is recorded. Record the image on the back of the paper.

In the post-processing unit 9, the recording paper is received from the printer 2 via the relay path 84, the recording paper is introduced by each of the carry-in rollers 50, the gate plate 52 is swung, and the recording paper is discharged to the respective discharge trays 56, 59. In addition, stable processing, sorting processing, and the like are performed as post-processing.

On the other hand, on the multi-stage paper feeder 6, the printer 2 and an optional paper discharge processor 5 are mounted. Further, the scanner 3 and the automatic document feeder 4 are mounted on a system rack 7. At the bottom of the multi-stage paper feeding device 6, each moving roller 63 and each fixing portion 64 are provided. When the fixing portions 64 are screwed into the bottom of the multi-stage paper feeding device 6 to separate the fixing portions 64 from the floor surface and the multi-stage paper feeding device 6 is supported by the moving rollers 63, the multi-stage paper feeding device 6 is moved. be able to. In this state, the multi-stage paper feeding device 6, the printer 2, and the paper ejection processing device 5 are moved and arranged inside the system rack 7. Thereafter, each fixing portion 64 is rotated and protruded, and each fixing portion 64 is brought into contact with the floor surface, and the multi-stage sheet feeding device 6 is fixed by each fixing portion 64.

Next, the multi-stage paper feeder 6 of the present embodiment will be described in more detail. In the multi-stage paper feeder of this embodiment, two paper storage trays 610 are arranged in the paper supply frame 111 as shown in FIG. 2, and a large number of recording papers are stored in each paper storage tray 610. Above each sheet storage tray 610, each separation supply unit 611 is rotatably supported.

Here, when the separation / feed unit 611 is rotated in the direction of the arrow, the entire upper side of the sheet storage tray 610 is opened. In this state, recording paper is supplied to the paper storage tray 610. When the separation and supply unit 611 is rotated in the direction opposite to the arrow, the pickup roller 621 of the separation and supply unit 611 comes into contact with the uppermost recording sheet in the sheet storage tray 610.
In this state, the pickup roller 621 is rotated,
The uppermost recording sheet is pulled out, and the recording sheet is transported between the drive feed roller 622 and the driven feed roller 623.

FIGS. 3, 4 and 5 are a schematic view showing the separation supply unit 611 when viewed from above, a schematic view when viewed from below, and a schematic view when viewed from the side. As apparent from FIGS. 3 to 5, in the separation and supply unit 611, the pickup roller 621 and the drive feed roller 62
2. Drive motor 624 and paper empty detection sensor 625
Are provided on the lower surface of the rotation support plate 626. The illustration of the driven feed roller 623 is omitted.

The rotation support plate 626 has a viewing window 626a, a rotation shaft 627, and a stopper 628. The rotation shaft 627 is supported on the upper side of the paper storage tray 610,
The separation supply unit 611 is rotatably supported. The stopper 628 abuts on a part of the sheet storage tray 610 during the rotation of the separation and supply unit 611 in the direction of the arrow in FIG.

The sheet empty detection sensor 625 is connected to the movable element 62.
5a. Here, in a state where a sufficient number of recording papers are stored in the paper storage tray 610, the recording paper in the paper storage tray 610 is used by the drive mechanism (not shown) while the bottom plate of the paper storage tray 610 is being lifted. The mover 625a of the empty detection sensor 625 is pushed up, and in response to the detection output of the empty paper detection sensor 625 at this time, the lifting of the bottom plate of the paper storage tray 610 is stopped. Placed at the height of Further, when the sheet storage tray 610 is almost empty, the movable element 625 a of the sheet empty detection sensor 625 can operate even if the bottom plate of the sheet storage tray 610 is raised to the upper limit.
The paper empty detection sensor 62 at this time is not pushed up.
Based on the detection output of No. 5, the empty state of the sheet storage tray 610 is determined.

The drive feed roller 622 is rotatably supported by a shaft. A gear 631 is fixed to a rotation shaft 622 a of the drive feed roller 622, and the gear 631 is meshed with a gear 632 of a drive motor 624. The drive motor 624 is connected to each gear 63.
The drive feed roller 622 is rotationally driven through 1,632.

The pickup roller 621 has a hole 621a formed in the center thereof, and is supported by a rotating shaft 635 passed through the hole 621a. Also, as shown in FIG. 6, a first coupling 633 is fixed to one end of the pickup roller 621, and an elastic engagement claw 634 is provided at the other end. On the other hand, the rotation shaft 635 is rotatably supported, and has a gear 636 and a second coupling 6 at one end.
37 is fixed, and an engagement groove 638 is formed at the other end. First coupling 6 of pickup roller 621
33 to the second coupling pickup 6 of the rotation shaft 635.
37, the elastic engaging pawl 634 of the pickup roller 621 is engaged with the engaging groove 638 of the rotating shaft 635 as shown in FIG. In this state, the elastic engagement claws 6
34 and the engagement groove 638 engage the pickup roller 6.
The movement of the rotary shaft 635 is transmitted to the pickup roller 621 through the first and second couplings 633 and 637. The drive motor 624 includes a gear 632, each gear 639, and a gear 636.
Shaft 635 and pickup roller 621 through
Is driven to rotate.

In the multi-stage paper feeder 6 having such a configuration, if the sheet storage tray 610 is pulled out from the main body of the multi-stage paper feeder 6, the degree of wear of the pickup roller 621 passes through the viewing window 626 a of the rotation support plate 626. And dirt around it can be easily confirmed visually. Or,
By rotating the separation supply unit 611 upward,
Since the rotation support plate 626 stands almost vertically, the state of the pickup roller 621, the drive feed roller 622, and the like can be easily confirmed.

The worn pickup roller 621
In the case of replacing, the separation supply unit 611 is rotated upward, and the rotation support plate 626 is set up almost vertically. In this state, as shown in FIG.
21 is disengaged from the engaging groove 638 of the rotating shaft 635, the pickup roller 621 is moved in the longitudinal direction, the first coupling 633 is detached from the second coupling 637, and the pickup roller 621 is detached. Pull out from the rotating shaft 635. Then, a new pickup roller 621 is inserted into the rotation shaft 635, and the first coupling 633 is engaged with the second coupling 637, and the elastic engaging claw 634 is engaged with the engaging groove 638.

That is, in the present embodiment, the rotation support plate 6
26 through the window 626a.
1 can be easily confirmed. Further, by rotating the rotation support plate 626 upward, confirmation and maintenance of the pickup roller 621, the drive feed roller 622, and the like can be easily performed. Further, the pickup roller 621 can be pulled out from the rotation shaft 635 simply by warping the elastic engagement claw 634 of the pickup roller 621 and disengaging it from the engagement groove 638 of the rotation shaft 635. 6
The new pickup roller 621 can be attached by simply inserting the pickup roller 621 into the pickup roller 621. When the pickup roller 621 is replaced, the pickup roller 621 may be replaced.
Since the other components are not removed at all, the mounting accuracy of the pickup roller 621 can be maintained.

The present invention is not limited to the above embodiment, but can be variously modified. For example,
A sheet feeding unit 21 equivalent to the separation feeding unit 611 is used.
May be provided. Further, the drive feed roller 622 may be replaced by a mechanism equivalent to the pickup roller 621.

[0040]

As described above, according to the present invention, the roller group is integrated and movably mounted on the main body of the sheet feeding apparatus. By moving the roller group, the state of the roller group can be confirmed and replaced. Can be easily performed.

Further, according to the present invention, since the window for viewing the roller group is provided, the state of the roller group can be more easily confirmed.

Further, according to the present invention, in order to remove the drive roller, the engagement between the other end of the drive roller and the drive shaft is released, and then the drive roller is moved in the longitudinal direction so that the drive roller is driven. Remove from To attach the drive roller, the drive roller is passed through the drive shaft, and one end and the other end of the drive roller are engaged with the drive shaft. Therefore, the drive roller can be easily replaced.

Further, according to the present invention, the roller group is rotatably supported on the shaft, and approaches and separates from the storage tray by the rotational movement. In a state where the roller group is brought close to the storage tray, the recording paper is drawn out of the storage tray by the roller group and conveyed, and in a state where the roller group is separated from the storage tray, the recording paper is supplied to the storage tray.

[Brief description of the drawings]

FIG. 1 is a side view illustrating an image forming apparatus to which an embodiment of a sheet feeding device according to the invention is applied.

FIG. 2 is a side view illustrating the multi-stage sheet feeding device according to the embodiment.

FIG. 3 is a schematic diagram illustrating a separation and supply unit in the multi-stage sheet feeding device of FIG. 2 as viewed from above.

FIG. 4 is a schematic diagram showing the separation and supply unit of FIG. 3 as viewed from below.

FIG. 5 is a schematic diagram showing the separation and supply unit of FIG. 3 as viewed from the side.

FIG. 6 is a side view showing a pickup roller of the separation and supply unit of FIG. 3;

FIGS. 7A and 7B are enlarged views showing a part of the pickup roller of FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Printer 3 Scanner 4 Automatic document feeder 5 Discharge processing apparatus 6 Multi-stage paper feeder 610 Paper storage tray 611 Separation supply unit 621 Pickup roller 622 Drive feed roller 623 Driven feed roller 624 Drive motor 625 Paper empty detection sensor 626 Rotation support plate

Continued on the front page (72) Inventor Shigetaka Hayashi 22-22, Nagaikecho, Abeno-ku, Osaka-shi, Japan Inside Sharp Corporation (72) Inventor Jinichi Nagata 22-22, Nagaikecho, Abeno-ku, Osaka-shi, Osaka Sharp shares In-company (72) Inventor Toshiki Ogita 22-22, Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Inside Sharp Corporation (72) Inventor Toyoaki Namba 22-22, Nagaike-cho, Abeno-ku, Osaka-shi, Osaka F-term (Reference) 3F343 FA02 FB02 FB03 FC22 GA01 GB01 GC01 GD01 JA02 JA14 JA19 JD04 JD09 JD33 KB04 KB05 KB13 KB15 LA04 LA16 LC14

Claims (4)

[Claims] An image forming apparatus that forms an image on a recording sheet and feeds the recording sheet by storing the recording sheet in a sheet feeding device of the image forming apparatus. A roller group for pulling out recording paper from the storage tray and transporting the recording paper to the image forming apparatus, wherein the roller group is integrated and movably mounted. 2. A sheet feeding device for an image forming apparatus according to claim 1, further comprising a window for viewing the roller group. 3. A drive roller of a roller group is passed through a drive shaft, and rotation of the drive shaft is transmitted to the drive roller by detachable engagement between one end of the drive roller and the drive shaft. 2. The sheet feeding device of the image forming apparatus according to claim 1, wherein movement of the driving roller in the longitudinal direction is restricted by detachable engagement with the driving shaft. 4. A roller group is rotatably supported on a shaft,
The sheet feeding device of the image forming apparatus according to claim 1, wherein the sheet feeding device approaches and separates from the storage tray by rotating.