JPH05294B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a sheet feeding device that is attached to a sheet intake port provided in an image forming apparatus such as a copying machine, a laser printer, a liquid crystal printer, or a printing machine.

[Technical background of the invention]

Generally, in image forming devices such as copying machines,
A paper feed cassette is attached to the sheet intake port to supply sheets such as copy paper, tracing paper, synthetic resin film, etc., but when copying a large amount at once, it is necessary to replenish the sheets frequently during copying. There must be.

Therefore, a sheet feeding device that accommodates a large amount of sheets is attached to the sheet intake port for a normal paper cassette installed in a copying machine, or to a specially provided sheet intake port to reduce the number of times sheets are replenished. ing.

Such a sheet feeding device includes a loading section that is inserted into a sheet intake port, a storage section that stores sheets, and a feeding means that feeds out the sheets stacked in the storage section, and copies through the loading section. The sheets are fed to a take-in means provided inside the machine.

[Problems with background technology]

However, in the case of a paper feed cassette, the take-in means can directly take in the sheets in the paper feed cassette, but in the case of a sheet supply device, the sheets in the storage section must be conveyed to the take-in means by the feed means. It won't happen. Therefore, sheets cannot be fed in time for high-speed copying machines and laser printers.

[Purpose of the invention]

An object of the present invention is to obtain a sheet feeding device with a high feeding speed.

[Summary of the invention]

In order to achieve the above object, the present invention includes a storage section for stacking and storing sheets, and a feeding means for contacting and feeding out the uppermost sheet of the sheets stacked in the storage section, and an image forming apparatus. In a sheet feeding device that is attached to a sheet intake port and supplies the sheet fed out from the storage portion to a capture means provided at the sheet intake port,
The feeding means has a predetermined interval in the sheet feeding direction, simultaneously contacts the uppermost sheet of the storage section at least at a leading end portion and a trailing end portion thereof, and feeds the uppermost sheet by advancing the uppermost sheet. When the trailing edge of the uppermost sheet passes through the rear end side portion of the feeding means and the rear end side portion of the feeding means comes into contact with the next sheet next to the uppermost sheet, the feeding means The top sheet is simultaneously fed by the leading edge portion, and the next sheet is fed by the trailing edge portion at the same time with a delay of the predetermined interval, and the leading edge of the top sheet is fed by the leading edge. A detection means for detecting that the sheet has reached the means, and a control means for stopping the feeding operation of the feeding means in response to a detection signal from the detection means, and at the same time feeding the uppermost sheet by the taking-in means. , when the uppermost sheet is fed by the take-in means, the next sheet is held by the rear end portion of the stopped feeding means that is in contact with the next sheet. This is a sheet feeding device.

[Embodiments of the invention]

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

As shown in FIG. 1, an image forming device such as a copying machine 3 is placed on a mounting table 1, and an image is formed by the sheet copying machine 3 supplied from a sheet feeding device 5 attached to this copying machine 3. It's getting old.

The mounting table 1 can be moved in and out between the guides 7 and 9, and accommodates a support plate 11 that supports the sheet feeding device 5 in the pulled out state, and a plurality of small-capacity paper feed cassettes 13 containing sheets of different sizes. It has a multi-stage cassette storage section 15.

The sheet feeding device 5 includes a sheet storage section 17 that stores sheets, and a sheet intake port 4 that will be described later.
1 , and a back cover 27 rotatably attached to the back of the sheet storage section 17 .

Further, as shown in FIG. 2, the sheet accommodating portion 17 includes a stacking portion, such as a hopper 29, which supports the sheet by abutting the tip against the tip regulating plate 28, and a third stacking portion.
As shown in the figure, a lifting device 31 is provided to move the hopper 29 up and down along a guide 30. The lifting device 31 includes a motor 33, a transmission mechanism 34 that transmits the driving force of the motor 33, a roller 35 to which the driving force is transmitted from the transmission mechanism 34, a belt 37 that connects the roller 35 and the hopper 29, and this belt 37. It is equipped with a roller 39 that supports.

When the hopper 29 is loaded with sheets, there are
A pair of support means, for example, support rollers 36 and 38 attached to the support member 26, are provided and supported by the guide 30 in a forwardly inclined state.

Furthermore, as shown in FIG. 2, a feeding means 101 is attached to a frame 102 above the sheet storage section 17 for feeding out the sheets stacked on the hopper 29 one by one.

This feeding means 101 includes feeding rollers 11 at the front and rear.
2,115, and is rotatably driven by the motor 103 to feed out the sheet. The rotational force of the motor 103 is the same as that of the motor 103 shown in FIG.
A gear 105 attached to a rotating shaft 104, a gear 106 meshing with this gear 105, this gear 1
A gear 108 attached to a shaft 107 of 06, a pair of left and right arms 109 rotatably attached to the shaft 107, a rotating shaft 110 attached to this arm 109, a gear 108 attached to this rotating shaft 110, It is transmitted via meshing gears 111 to a feeding roller 112 attached to a rotating shaft 110. The feeding roller 112 is a one-way clutched roller that rotates in one direction, and can be moved up and down by an arm 109.

A frame 113 is rotatably attached to the rotating shaft 110, and a feeding roller 115 is attached to a rotating shaft 114 provided at the rear of the frame 113. The driving force is transmitted to the feeding roller 115 by a pulley 116 attached to the rotating shaft 110, a pulley 117 attached to the rotating shaft 114, and a belt 118 stretched between the pulleys 116 and 117, as shown in FIG. It is done through.

The mounting portion 19 includes a guide 123 that guides the sheet sent out by the feeding roller 103, and a shaft 12.
A pressing plate 127 that rotates around 5, this pressing plate 1
A solenoid 129 for rotating the sheet 27, and a sheet detection sensor 131 having a light emitting element and a light receiving element for detecting whether or not the sheet is in the setting section are provided. Note that the return of the pressing plate 127 is performed by a spring 131.

On the other hand, the copying machine 3 is provided with a sheet intake port 41 into which the mounting portion 19 of the sheet feeding device 5 is inserted, as shown in FIG. In this sheet intake port 41, a sheet feeding device 5 is provided as shown in FIG.
A sheet take-in means, for example a take-in roller 47, with which the pressing plate 127 engages is provided.

The copying machine 3 is also provided with an intake port 51 into which the paper feed cassette 13 is inserted. Note that a take-in roller 53 is provided within this take-in port 51 .

Registration rollers 55 and a conveyor belt 57 are provided ahead of the take-in rollers 47 and 53 to feed the sheet to an image forming section 58.

The image forming section 58 is provided with a photosensitive drum 59. Around this photosensitive drum 59, a charging device 61, an unnecessary charge eraser 63, a developing device 6
5, a transfer device 67, a separation charge device 69, a separation claw 71, and a drum cleaner 73 are arranged.

An automatic document feeder 75 is attached to the document setting section so that its rear side can be opened and closed by a hinge.

A platen 77 made of contact glass is provided below the automatic document feeder 75, and a slit illumination device 79 is provided below the platen 77 so as to be movable in the left-right direction along the platen 77.

In addition, two movable reflecting mirrors 81 and 83 and a lens 8
5 and two fixed reflecting mirrors 87 and 89 transmits a light image of the original image illuminated by the slit illumination device 79 to the photosensitive drum 59, and performs exposure. There is.

The photosensitive drum 59 forms an electrostatic latent image corresponding to the image of the document on its outer peripheral surface, and this latent image is transferred to the developing device 6.
Visualization with toner is performed by 5.

The visible image formed on the photosensitive drum 59 in this way is captured by the capture roller 51 or 53, the paper feeding timing is adjusted by the registration roller 55, and the visible image is sent between the photosensitive drum 59 and the transfer device 67. The image is transferred onto the sheet P.

The sheet with the visible image transferred in this way is
The photosensitive drum 59 is separated from the photosensitive drum 59 by the discharging action by the separation charging device 69 and the mechanical separation action by the separating claw 71, and is sent to the fixing device 93 by the conveyance roller 91.

The transfer sheet is operated from a discharge port 97 with the visible image facing upward by a carry-out roller 95, and is stored in a sheet processing device 99.

This sheet processing device 99 has a folding function (folding device) and a sorting function (sorter),
Conveyance path 151, conveyance rollers 153, 155, conveyance path switching gate 157, folding roller 15
9,161,163, size switching gate 16
5. Folding path 167, 169, roller 17
Suction belt 1 supported vertically by 1,173
75, a distributor 177, and a plurality of trays 179. Note that the folding path 167 is, for example,
The folding path 169 is for B4 size, and the folding path 169 is for A3 size, for example.

The automatic document feeder 75 includes a document tray 201 on which a document is set, a separation and feeding section 203 that separates the document set on the document tray 201 into one sheet and sends them out, and a separation and feeding section 203 that separates the document set on the document tray 201 into one sheet and sends them out, and a document feeder 203 that separates the document set on the document tray 201 into one sheet and sends them out. A transport unit 205 transports the document onto the platen 77, sets it at a reference position value, and sends the document out from the platen 77 after copying is completed; A storage tray 209 for storing sheets discharged from the section 207 is provided.

With the above configuration, this device operates as follows.

First, the back cover 27 of the sheet feeding device 5 is opened and a sheet is set on the hopper 29. Since the hopper 29 is inclined, the leading edge of the sheet abuts against the leading edge regulating plate 28. Also, Hotupa 29
Since the support position of is located behind the center of gravity,
The weight of the seat causes the hopper 29 to tilt further forward. Therefore, the sheet does not shift toward the rear of the hopper 29.

In this state, when the back cover 27 is closed, the motor 33 is automatically driven and the roller 35 is
to raise the hopper 29. When the sheet pushes up the feeding rollers 112 and 115 and a sensor (not shown) turns on, the feeding rollers 112 and 115 stop. Then, the motor 103 is driven, and the feeding rollers 112 and 115 are rotated.

Therefore, when the uppermost sheet is sent out by the feeding rollers 112 and 115 and the trailing edge of the sheet passes the feeding roller 115, the uppermost sheet is sent out by the feeding roller 115.
2, the feeding roller 115 feeds out the next sheet. The tip of the previous sheet is the sensor 133
When detected, the motor 103 stops, the rotation of the feeding rollers 112 and 115 stops, and
The solenoid 129 is energized, the press plate 127 rotates, and the sheet is pressed against the take-in roller 47 .

On the other hand, the document tray 20 of the automatic document feeder 75
1 and press the copy button (not shown), the document is separated into one sheet by the separating and feeding unit 203 and sent out, and the conveying unit 205 transfers the document to the platen 7.
It is set to the reference position on 7. Note that when copying is completed, the document is discharged to the storage tray 209 via the discharge section 207, and the next document is supplied from the separation and feeding section 203.

When the original is set at the reference position on the platen 77, a command to take in the sheet is issued from the copying machine 3.
The take-in roller 47 rotates and the sheet is transferred to the copying machine 3.
taken within. When the trailing edge of the sheet is detected by the sensor 133, the solenoid 129 is de-energized, the press plate 127 moves away from the take-in roller 47, the motor 103 rotates, and the feed rollers 112 and 115 feed the next sheet. send out.

Note that when a predetermined amount of sheets are taken in, the hopper 2
9 rises by a certain amount, and the sheet always moves to the feeding roller 11.
It is in contact with 2,115.

The image of the thus captured sheet is copied by the image forming section 58 and is supplied to the sheet processing device 99.

When the sheet needs to be folded to B4 size or A3 size, it is supplied to folding rollers 159 and 161 through a conveyance path 151. When the sheet to be folded is B4 size, the size switching gate 165 is switched as shown by the solid line, and when the sheet is A3 size, it is switched as shown by the broken line.

When the edge of the sheet hits the tip of the folding path 167 or 169, the sheet is deflected, and the deflected portion is gripped by folding rollers 161, 163, folded, and stored in a tray 179 designated by a distributor 177.

When there is no need to fold the sheet, the conveyance path switching gate 157 is switched as shown by the broken line,
The tray 179 designated by the distributor 177 accommodates the tray 179 .

According to this embodiment described above, the following effects can be obtained.

(1) Two feeding rollers 11 in the sheet feeding direction
Since 2,115 are lined up, while the sheet is being fed out, the feeding of the next sheet is started, and the next sheet is placed in a first-feeding state. Therefore, even if the distance between the storage section 17 and the take-in roller 47 is long,
The distance between the leading edge of the next sheet and the take-in roller 47 is shortened, the time required for the sheet to reach the take-in roller 47 is shortened, and the sheet can be fed at high speed.

(2) Since the take-in roller 47 pulls out the uppermost sheet while the feed roller 115 is holding down the next sheet, the next sheet does not follow and is not double fed.

[Modified example]

Although one embodiment of the present invention has been described above,
The present invention is not limited to the embodiment described above; for example, in the embodiment described above, two feeding rollers 11
Although belts 2 and 115 are arranged side by side in the feeding direction, even one belt can start feeding out the next sheet while feeding out the next sheet.

〔Effect of the invention〕

As described above, according to the present invention, an image forming apparatus includes a storage section for stacking and storing sheets, and a feeding means for contacting and feeding out the uppermost sheet of the sheets stacked in the storage section. In a sheet feeding device that is attached to a sheet intake port and supplies sheets fed out from a storage section to a capture means provided at the sheet intake port,
The feeding means has a predetermined interval in the sheet feeding direction, simultaneously contacts the uppermost sheet of the storage section at least at a leading end portion and a trailing end portion thereof, and moves the uppermost sheet by advancing the uppermost sheet. When the trailing edge of the upper sheet passes through the rear end side of the feeding means and this end side of the feeding means comes into contact with the next sheet next to the uppermost sheet, the leading edge of the feeding means Detection means for simultaneously feeding the topmost sheet and the next sheet by the rear end side with a delay of the predetermined interval, and detecting that the leading edge of the topmost sheet has reached the taking-in means. and control means for stopping the feeding operation of the feeding means in response to a detection signal from the detection means and simultaneously feeding the uppermost sheet by the taking-in means, so that the uppermost sheet is not fed by the taking-in means. When the next sheet is loaded, the next sheet is held by the rear end portion of the stopped feeding means that is in contact with the next sheet, so the next sheet overlaps the top sheet with a slight delay. At the same time, even though the next sheet overlaps the topmost sheet, the taking-in means is fed with the rear end of the feeding means holding down the next sheet. We were able to create a sheet feeding device that takes in the topmost sheet and is less likely to cause double feed.

[Brief explanation of the drawing]

1 to 4 are diagrams showing one embodiment of the present invention, and FIG. 1 is a sectional view showing the overall configuration of a mounting table, a copying machine, a sheet feeding device, an automatic document feeder, and a sheet processing device; FIG. 2 is a sectional view showing the internal structure of the sheet feeding device, FIG. 3 is a side view showing the structure of the elevating device of the sheet feeding device, and FIG. 4 is a view showing the structure of the feeding means. DESCRIPTION OF SYMBOLS 1... Placing table, 3... Copying machine, 5... Sheet supply device, 11... Large capacity storage section, 17... Sheet storage section, 19... Mounting section, 26... Support member, 2
8...Tip regulation plate, 29...Hopper, 31
... Lifting device, 36, 38 ... Support roller, 41
... Sheet intake port, 47 ... Take-in roller, 75 ... Automatic document feeder, 99 ... Sheet processing device, 101 ... Feeding means, 112, 115
... Feeding roller, 127 ... Pressing plate.

Claims (1)

[Claims] 1. The image forming apparatus 3 is equipped with a storage section 17 for stacking and storing sheets, and a feeding means 101 for contacting and feeding out the uppermost sheet of the sheets stacked on the storage section 17. In the sheet feeding device 5 that is attached to the sheet intake port 41 and supplies the sheet fed out from the storage section 17 to the intake device 47 provided in the sheet intake port 41, the feeding device 101 is configured to feed the sheet. The uppermost sheet has a predetermined interval in the feeding direction, and is in contact with the uppermost sheet of the storage section 17 at least at the leading end and rear end thereof, and as the uppermost sheet moves forward, the rear edge of the uppermost sheet The feeding means 10
When the rear end side portion of the feeding means 101 comes into contact with the next sheet next to the uppermost sheet, the leading end side portion of the feeding means 101 passes through the rear end side portion of the feeding means 101. The uppermost sheet is simultaneously fed with the next sheet being delayed by the predetermined distance by the rear end side portion, and the leading edge of the uppermost sheet is conveyed to the taking-in means 4.
a detection means 133 for detecting that the sheet has reached 7, and a detection signal from the detection means 133 to stop the feeding operation of the feeding means 101, and at the same time control the feeding means 47 to feed the uppermost sheet. means 129, when the uppermost sheet is fed by the taking-in means 47, the next sheet is placed on the rear end side of the stopped feeding means 101 that is in contact with the next sheet; A sheet feeding device characterized in that the sheet feeding device is held by a portion. 2. In the sheet feeding device according to claim 1, a leading end portion and a trailing end portion of the feeding means 101 are provided with a first roller 112 and a second roller provided at a predetermined interval in the sheet feeding direction, respectively. 2. A sheet feeding device comprising: two rollers 115; 3. In the sheet feeding device according to claim 1, the feeding means is constructed by winding a belt member between belt rollers arranged at a predetermined interval in the sheet feeding direction. Characteristic sheet feeding device.