JPH07215531A - Sheet feeding device and image forming device - Google Patents

Abstract

PURPOSE:To shrink the occupied space when a jam is processed, sufficiently secure the jam processing space, and improve the visibility of a jammed sheet and the workability for jam processing. CONSTITUTION:An inversion guide 9 and the second feed section 12 are integrally formed as a right door unit, only the right door unit is rotated clockwise centering on the rotation center 20a without rotating a multi-tray 11, and the inversion guide 9 is rotated to the position shown by a broken line centering on the rotation center 9a. A conveyance path delivered from a sheet feed cassette 7 is almost visible from the outside of the device, and an inversion conveyance path of sheets can be opened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding apparatus for feeding a sheet mounted on an image forming apparatus such as a copying machine or a printer.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus such as a copying machine or a printer, a cassette feeding device for feeding recording paper from a paper feed cassette accommodating and stacking a plurality of recording papers and a manual feed from an openable tray. There is a device equipped with a multi-manual feeding device that supplies and feeds the recording paper. For example, in the copying machine shown in FIG.
a cassette feeding device C that feeds the recording paper P from a and 51b by the feeding rollers 52a and 52b, and multi-manual feeding that feeds the recording paper P from the manual feed tray T that can be opened and closed to the apparatus main body. The feeding device M is equipped. The recording paper P supplied from the cassette feeding device C is reversely conveyed, passes through the paper path Q, and is guided to the registration roller pair 54. The recording paper P supplied from the multi-manual feeder M is directly guided to the registration roller pair 54.

The jam handling mechanisms of the cassette feeding device C and the multi-manual feeding device M are individually provided. That is, the jam (paper jam) generated in the paper path Q or the cassette feeding device C is jammed by opening the opening / closing door D, and the jam generated in the multi-manual feeding device M is moved to the manual feeding tray T. Jam processing is performed through the opening E formed on the side surface of the apparatus main body by opening.

Further, as described in Japanese Utility Model Publication No. 2-15881, a manual feed tray for manually inserting sheets one by one is constructed integrally with a reversing guide of a cassette feeding device, and is manually fed during jam processing. When the tray is opened, the reversing guide is also opened at the same time, and the jam clearance space is secured.

[0005]

In the copying machine equipped with the cassette feeding device C and the multi-manual feeding device M shown in FIG. 5, the paper path Q (registration roller pair) is especially used.
54) If a jam occurs in the area before 54, the door D must be opened to remove the jammed paper. However, the multi-manual feeding device M having the manual feeding tray T is an obstacle during the jam processing and makes it difficult to perform the work. Particularly in a configuration in which the paper path from the paper feed cassettes 51a and 51b to the registration roller pair 54 is reversed and conveyed, the recording paper P is curved and conveyed at the reversing portion, so that the resistance is large. The incidence of jams was high. On the other hand, in the configuration of the conventional feeding device, since the jam processing space is small, it is difficult to find the jammed paper, and the jam processing work is troublesome and takes time.

Further, in the technique disclosed in Japanese Utility Model Publication No. 2-15881, since the manual feed tray is integrally formed with the reverse guide of the cassette feeding device, the reverse guide is also opened when the manual feed tray is opened during the jam processing. Although it is opened, the jam clearance space can be expanded, but the recording paper on the tray may drop due to the rotation of the manual feed tray. In addition, there is a problem that a large portion is rotated during the jam processing, and an occupied space of a device required for the jam processing is increased.

An object of the present invention is to solve the above-mentioned problems of the prior art, reduce the occupied space during jam processing, and secure a sufficient jam processing space to improve the visibility of the jam sheet and the workability of the jam processing. An improved sheet feeding apparatus is provided.

[0008]

A typical means for solving the above-mentioned problems of the prior art and applied to the embodiments described below is a first feeding section for feeding sheets from the sheet storing means in which the sheets are stacked and stored. A first feeding means equipped with a reversing guide means for reversing and guiding the sheet sent out from the first feeding section, a stacking guide means for stacking and supplying a plurality of sheets, and the stacking A sheet feeding device having a second feeding unit equipped with a second feeding unit for feeding the sheet supplied from the guiding unit, comprising: a reversing guiding unit of the first feeding unit; It is characterized in that it is configured as a separate body from the loading guide means of the feeding means and has a separate center of rotation, and the reversing guide means and the second feeding portion are unitized and integrally configured. And

[0009]

According to the above means, for example, when the reversing guide means and the second feeding section are integrally formed as a door unit,
Without rotating the stacking guide means, only the door unit can be rotated to open the sheet reversal conveyance path widely.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a sheet feeding apparatus according to an embodiment of the present invention to which the above means is applied will be described. The present embodiment will be described using a sheet feeding device equipped in a copying machine. 1 is a cross-sectional view showing a schematic configuration of a copying machine, FIG. 2 is an explanatory view showing a state in which a multi-tray of the copying machine is opened, FIG. 3 is an explanatory view when a door unit is opened, and FIG. 4 is a door unit and a multi-tray. It is explanatory drawing which shows the relationship with.

(Overall structure)

First, a schematic structure of a copying machine will be described with reference to FIGS. In FIG. 1, reference numeral 1 denotes a document table glass for placing a document on which a document to be copied is placed. Reference numeral 2 denotes an exposure device which moves in the direction of arrow A and scans the entire surface of the original while irradiating the original placed on the original table glass 1 with light.

The reflected light obtained by illuminating the original with the exposure device 2 is imaged on the photosensitive drum 5 via the first mirror group 3a, the zoom lens 4 and the second mirror group 3b. An electrostatic latent image is formed.

The photosensitive drum 5 is provided in a process cartridge 6 provided with a plurality of process means for contributing to image formation on the periphery thereof, and a charging means, a developing means, a cleaning means and the like are provided around the photosensitive drum 5. It is arranged. The electrostatic latent image formed on the photosensitive drum 5 is developed by the developing means and visualized.

Reference numeral 7 denotes a sheet feeding cassette as sheet storing means for stacking and storing sheets P such as recording sheets. A first feeding unit 8 is equipped with a feeding roller 8a that feeds the sheet P from the paper feeding cassette 7, a separation pad 8b that presses the feeding roller 8a, and the like. Reference numeral 9 denotes a reversing guide as a reversing guide means, which reverses and conveys the sheet P fed by the feeding roller 8a. Further, 10a, 10b and 10c are upper, middle and lower guides for guiding the conveyance of the sheet P.

In FIG. 2, reference numeral 11 denotes a multi-tray as a loading guide means, which is rotatably attached to the right side surface of the apparatus main body. A second feeding unit 12 is equipped with a feeding roller 12a for feeding the sheets P stacked on the multi-tray 11 and a supporting arm 12c for supporting a separation pad 12b pressed against the feeding roller 12a.

Further, in FIG. 1 and FIG. 2, reference numeral 13 denotes a pair of registration rollers as a conveying means, and the sheet feeding cassette 7
Alternatively, the sheet P supplied from the multi-tray 11 is synchronized with the developed image formed on the photosensitive drum 5 and conveyed to the transfer section. A transfer roller 14 is in pressure contact with the photosensitive drum 5. The transfer roller 14 constitutes an image forming means for forming an image on the sheet P together with the process cartridge 6. That is, the developed image is transferred to the sheet P conveyed by the registration roller pair 13 when passing between the photosensitive drum 5 and the transfer roller 14. The sheet P after the image transfer is conveyed by the conveying device 15 and is fixed by the fixing device.
When passing through 16, heat and pressure are applied to fix the transferred image. Then, the sheet P after the image fixing is conveyed and discharged to the discharge tray 18 by the discharge roller pair 17.

(Structure of Sheet Feeding Device)

Next, the structure of the sheet feeding device in the copying machine will be described. The present embodiment is equipped with two feeding means, and their configurations will be described below in order.

(First feeding means)

1 and 2, the paper feed cassette 7
Is detachably attached to the bottom of the apparatus main body, and pushes up the intermediate plate 7a by a pressing means such as a spring (not shown) to press the sheet P stacked on the intermediate plate 7a against the feeding roller 8a. A frictional force is generated between them. In addition, the separation pad 8b of the first feeding unit 8 is a pressing spring 8c.
It is pressed by and is pressed against the feeding roller 8a.

When the feeding roller 8a rotates, it is fed from the uppermost sheet P, and when it passes between the feeding roller 8a and the separation pad 8b, it is fed one by one.
Then, the feeding roller 8a, the reverse guide 9, and the middle guide 10b
And the lower guide 10c, and further, a reversing conveyance path formed between the upper guide 10a and the lower guide 10c.

(Second feeding means)

The support arm 12c of the second feeding section 12 is biased by a spring in a direction in which the separation pad 12b presses the feeding roller 12a, and the middle plate 12d is centered on a fulcrum by a cam (not shown). It can be rotated vertically. Above multi tray
When the sheet P is set to 11 and the copy button is pressed, the middle plate 12d is raised by the cam, the sheet P is brought into pressure contact with the feeding roller 12a, and then the feeding roller 12a is rotated to start the movement of the sheet P. The middle plate 12d is lowered to the original position, and the pressure contact of the sheet P with the feeding roller 12a is released. As a result, the sheet P that has started to move is separated from the separation pad 12b.
By this, only the uppermost side is separated and sent out. Then, the upper guide 10a, the middle guide 10b, and further the upper guide 10a
And the lower guide 10c.

In the above structure, the sheet P fed from the paper feed cassette 7 or the multi-tray 11 is guided to the registration roller pair 13 which is temporarily stopped. The sheet P sent out from the paper feed cassette 7 is inverted and conveyed by the inversion guide 9 and the middle guide 10b. The middle guide 10b is composed of a rib formed on the right door 19 which also serves as the exterior of the device. Further, the right door 19 has a middle guide 10b, a feeding roller 12a constituting the second feeding means, a separation pad.
12b, support arm 12c, middle plate 12d, etc. are integrally attached to form a unit structure (hereinafter referred to as "right door unit 20"), and the number of parts is reduced. This right door unit 20 is attached to the main body of the apparatus so as to be rotatable about a rotation center 20a, and is provided separately from the rotation center of a multi-tray 11 which will be described later. It is configured to rotate.

(Jam processing method)

Next, a jam handling method when a jam occurs on the upstream side of the registration roller pair 13 in the sheet conveying direction (between the upper and lower guides 10a and 10c) will be described with reference to FIG. First, by pulling the handle 20b of the right door unit 20 arranged coaxially with the positioning hook of the device body, the hook is rotated and the connection with the device body is released, and the right door unit 20 is rotated about the rotation center 20a. It rotates clockwise and moves to the position shown in FIG. By rotating the reversing guide 9 around the rotation center 9a to the position shown by the broken line in the figure, the conveyance path sent out from the sheet feeding cassette 7 can be almost visually observed from the outside of the apparatus, and the jam sheet can be easily found. In addition, it is possible to secure a sufficient jam clearance space.

In addition, since the right door unit 20 and the multi-tray 11 have separate pivot centers, each has its own pivotal structure. A space corresponding to the length L of the multi-tray 11 is not required as compared with the above. Therefore, it is possible to reduce the area occupied by the device during the jam processing.

Further, when the right door unit 20 is rotated, it is not necessary to rotate a portion corresponding to the multi-tray 11, so that the operability is good and the multi-tray 11 is damaged by an excessive force applied. There is no fear of doing it. Further, when the sheets P are stacked on the multi-tray 11,
Does not rotate, so there is no risk of the stacked sheets falling.

Next, the right door unit 20 and the multi-tray
The relationship of 11 will be described with reference to FIG. Right door unit 20
The rotation center of the tray is 20a, and the rotation center of the multi-tray 11 is 11a shown by the chain double-dashed line in the figure. By vertically shifting the rotation center 11a of the multi-tray 11 and the rotation center 20a of the right door unit 20, when the multi-tray 11 is opened as shown by the chain double-dashed line in the figure, the right door unit 20 is rotated. The sheet P is configured to enter the second feeding unit 12 that is integrally provided.

An upper right door 21 is provided coaxially with a rotation center 20d of a hook 20c for fixing the right door unit 20 to the main body of the apparatus. The upper right door 21 is constantly biased in the direction of arrow a by biasing means such as a torsion coil spring. The upper right door 21 also serves as an exterior between the right door 19 and the multi-tray 11 except when feeding from the multi-tray 11. A rib 21a is formed on the upper right door 21, and a protrusion 11b corresponding to the rib 21a is formed on the multi-tray 11. When the multi-tray 11 is rotated to the position indicated by the chain double-dashed line in the figure, the projection 11b pushes down the rib 21a, so that the upper right door 21 is pushed down to the position shown by the chain double-dashed line. Further, when the multi-tray 11 is closed to the apparatus main body as shown by the solid line, the upper right door 21 is rotated in the direction of arrow a by the biasing means such as the torsion coil spring as described above, and the apparatus is shown as the solid line. Stand still in the closed state.

By providing the upper right door 21 which rotates separately from the right door unit 20, the area shown by Y in FIG. 3 can be used during the jam clearance work, and the visibility of the jam sheet and the jam clearance space are enlarged. Workability can be improved. The upper right door 21 is a multi-tray
Since it is configured to rotate in conjunction with 11,
The operability in the opening / closing operation of the multi-tray 11 is not deteriorated, and it is possible to contribute to downsizing of the multi-tray 11.

Although the sheet feeding device equipped in the copying machine has been described in the present embodiment, the image forming device is not limited to this, and other devices such as a facsimile device, an ink jet printer, a laser beam printer, etc. Device may be used.

[0034]

As described above, according to the present invention, the reversing guide means of the first feeding means and the stacking guide means of the second feeding means are formed separately and have different rotation centers. Since the reversing guide means and the second feeding portion are unitized and integrally configured, for example, when the reversing guide means and the second feeding portion are unitized with the opening / closing door and integrally configured as a door unit, Only the door unit can be rotated without rotating the stacking guide unit to open the sheet reversal conveyance path widely. Therefore, it is possible to reduce the area occupied by the device during the jam processing and improve the operability. Further, since the stacked sheets are not rotated in the stacking guide means, the stacked sheets do not fall.

Further, the reversing guide means is rotatably attached to the opening / closing door. When a door which can be rotated separately from the opening / closing door is provided, the visibility of the jam sheet and the jam clearance space are improved. It is possible to improve the workability of the jam processing by enlarging the size.

By rotating the door in conjunction with the loading guide means, it is possible to maintain good operability in the opening / closing operation of the loading guide means, and further downsize the loading guide means. Can contribute to.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a schematic configuration of a copying machine.

FIG. 2 is an explanatory diagram showing a state in which a multi-tray of the copying machine is opened.

FIG. 3 is an explanatory diagram when a door unit is opened.

FIG. 4 is an explanatory diagram showing a relationship between a door unit and a multi-tray.

FIG. 5 is an explanatory diagram showing a configuration of a conventional copying machine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Original glass stand 2 ... Exposure device 3a ... 1st mirror group 3b ... 2nd mirror group 4 ... Zoom lens 5 ... Photosensitive drum 6 ... Process cartridge 7 ... Paper feed cassette 7a, 12d ... Middle plate 8 ... 1st feeding Part 8a, 12a ... Feeding roller 8b, 12b ... Separation pad 9 ... Inversion guide 9a, 20a, 20d ... Rotation center 10a, 10b, 10c ... Guide 11 ... Multi-tray 12 ... Second feeding part 12c ... Support arm 13 … Registration roller pair 14… Transfer roller 15… Conveying device 16… Fixer 17… Ejection roller pair 18… Ejection tray 19… Right door 20… Right door unit 20b… Grip 20c… Hook 21… Right door 21a… Rib

Claims (5)

[Claims] 1. A first equipped with a first feeding section for feeding out a sheet from a sheet accommodating means in which sheets are stacked and stored, and a reversing guide means for reversing and guiding the sheet fed out from the first feeding section. A second feeding means equipped with a first feeding means, a stacking guide means for stacking and supplying a plurality of sheets, and a second feeding section for sending out the sheets supplied from the stacking guide means; In the sheet feeding apparatus having the above, the reversing guide means of the first feeding means and the stacking guide means of the second feeding means are formed as separate bodies and have different rotation centers, The sheet feeding apparatus, wherein the second feeding unit is unitized and integrally configured. 2. The inversion guide means of the first feeding means and the second feeding portion of the second feeding means are unitized as an opening / closing door and integrally provided. The sheet feeding device described. 3. The reversing guide means is rotatably attached to the open / close door, and a door provided between the open / close door and the loading guide means is rotatable separately from the open / close door. The sheet feeding apparatus according to claim 2, further comprising: 4. The sheet feeding apparatus according to claim 3, wherein the door rotates in conjunction with the stacking guide means. 5. The sheet feeding apparatus according to claim 1, a feeding unit for feeding the sheet fed by the sheet feeding apparatus, and a sheet fed by the feeding unit according to image information. An image forming apparatus equipped with an image forming unit for forming an image.