JPH048341B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a sheet feeding device installed in 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; The present invention relates to a sheet conveyance device such as an automatic document feeder that automatically supplies a document to a platen of an image processing device such as a copying machine, facsimile machine, or image reader.

[Conventional technology]

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 has a loading section that is inserted into a sheet intake port, a hopper that loads sheets, a lifting device that moves the hopper up and down, and a feeding device that feeds out the sheets loaded on the hopper. The sheet is then fed into the copying machine through the loading section.

[Problem that the invention seeks to solve]

In such a sheet feeding device, separation claws are provided at both front ends, similar to a paper feed cassette, and the sheets sent out by the feeding means are bent against the separation claws and bounced beyond the elastic limit, thereby separating the sheets into one sheet. Separated.

However, since the reliability of separation performance is low, if high separation performance is required, a feeding roller that rotates in the sheet conveyance direction and a separation roller that rotates in the opposite direction to the sheet conveyance direction are pressed into contact. The sheet is then fed to the copying machine while being separated.

However, since the feed roller and the separation roller rotate in opposite directions while in pressure contact with each other, it is difficult for the sheet to be gripped, and the sheet is likely to skew when gripped.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a sheet conveyance device that easily grips sheets when separating the sheets and is less likely to skew.

[Means for solving problems]

In order to achieve the above object, the present invention provides a sheet conveying device that separates and conveys a plurality of sheets into one sheet, in which a plurality of first feeders are provided in a direction intersecting the sheet conveying direction, and a first feeding device for conveying the sheets is provided. a plurality of first separation means provided in a direction intersecting the sheet conveyance direction and for rejecting the sheet following the sheet conveyed by the first feeding means;
a plurality of second feeding means, which are provided in a direction intersecting the sheet conveyance direction, and convey the sheets separated and sent out by the first feeding means and the first separating means; a plurality of second separation means provided in a crossing direction and for rejecting sheets that follow sheets conveyed by the second feeding means, the first feeding means and the first separation means; are smaller than the respective numbers of the second feeding means and the second separating means, and the first feeding means, the first separating means, and the second feeding means The second separating means are arranged alternately and overlapped in opposite directions, and the amount of overlap between the first feeding means and the first separating means is adjusted to the amount of overlap between the second feeding means and the first separating means. The amount of overlap with the second separation means was made smaller.

[Embodiments of the invention]

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

<Overall Configuration> As shown in FIG. 1, an image forming device such as a copying machine 3 is placed on a mounting table 1, and a document fed from an automatic document feeder 75 to a platen 77 of the copying machine 3 is placed on a sheet. The information is copied onto sheets supplied from the supply device 5 and stored in a sorter 99.

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

<Sheet Supply Device 5> The sheet supply device 5 includes a sheet storage section 17 that stores sheets, and a mounting section 19 that guides sheets inserted into a sheet intake port 41 (described later) and sent out from the sheet storage section 17 to the copying machine 3. , and a back cover 27 rotatably attached to the back of the seat 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 and
a transmission mechanism 34 that transmits the driving force, and a take-up roller 35 to which the driving force is transmitted from the transmission mechanism 34.
, a belt 37 that combines the take-up roller 35 and the hopper 29, and a roller 39 that supports the belt 37.

Although not shown, there is a down switch that lowers the hopper 29. If you press it with the cover 27 closed, the hopper 29 will lower. If you open the cover 27 while it is descending, it will be turned off for safety. Stop. Further, since the operator wants to open the cover 27 to replenish sheets or clear jammed sheets, when the down switch is pressed while the cover 27 is open, the down switch is lowered, and when the down switch is pressed again, the down switch is stopped.

When the hopper 29 is loaded with sheets, there are
A pair of support means, such as support rollers 36 and 38 attached to the support member 26, are provided and supported by the guide 30 in a forwardly inclined state. The hopper 29 also has an empty detection hole 101 and notches 103, 105, 10 as shown in FIG.
7,109 are provided.

Furthermore, a support plate 115 is attached to the upper part of the sheet accommodating portion 17 between the side plates 111 and 113 as shown in FIG. This support plate 115 is provided with guide grooves 117 and 119.

Sliders 121,
123 guide shafts 125, 127, 129, 13
1 is inserted. Note that the slider 121,
123 are connected by a rack and pinion (not shown), so that no matter which of the sliders 121 and 123 is slid, both move by the same amount.

Hanging regulating plates 133, 135, 137, 139 are attached to the outside of the sliders 121, 123. In addition, the regulation plates 133, 135, 13
7,139 are notches 103, 105, 10
7 and 109 correspond to each other.

An empty sensor lever 141 and a level sensor lever 143 are rotatably attached to the center of the support plate 115, and the empty state and level of the sheet are detected by, for example, a transparent empty sensor 145 and a level sensor 147. ing. In addition, the empty sensor 145 and the level sensor 14
7 has a step at its mounting position, and the empty sensor 145 is mounted at a slightly higher position. Further, a pair of stoppers 149 and 151 are attached to the front of the support plate 115.

The mounting portion 19 has a guide 153, as shown in FIG.
A conveyance path 159 is formed by 155 and 157, and a cover 154 is attached so as to be openable and closable via a hinge 156 as shown in FIG. is raised together with the cover 154, and the sheet jam in the conveyance path 159 can be cleared.

In addition, the mounting portion 19 includes a feeding unit 161 that feeds out the sheet on the hopper 29, a first feeding unit 163 that rotates in the sheet feeding direction, and a feeding unit 161 that feeds out the sheet on the hopper 29, with the conveying path 159 in between. A first separating means 16 that is arranged to face the sheet and rotates in the opposite direction to the sheet conveying direction to reject the sheet that follows the sheet conveyed by the first feeding means 163.
5, a second feeding means 167 for conveying the sheet separated by the first feeding means 163 and the first separating means 165, and a second feeding means 167 disposed opposite to the second feeding means 167. The second feeding means 167 rotates in the opposite direction to the conveying direction of the sheet.
a second separating means 169 for rejecting the sheet following the sheet conveyed by the second separating means 169; and a second feeding means 16
A registration means 171 that once receives the sheet sent out while being separated by the second separation means 7 and the second separation means 169 and registers the leading edge thereof, and a sensor 173 that detects the sheet reaching the registration means 171 are provided.

The first feeding means 163 includes two feeding rollers 183 attached to a rotating shaft 179 via a one-way clutch 181, as shown in FIG. The one-way clutch 181 is connected to the rotating shaft 179
When the feed roller 1 rotates in the sheet conveying direction,
83, and when the rotary shaft 179 rotates in the opposite direction, the drive is not transmitted.

A rotating shaft 179 is supported by bearings 301 and 303, and a gear 307 with a spring clutch 305;
An arm 311 with a spring clutch 309, a pulley 313 and an arm 317 with a spring clutch 315 are attached.

The spring clutch 305 fixes the gear 307 to the rotation shaft 179 when the gear 307 rotates in the sheet conveyance direction, and causes the gear 307 and the rotation shaft 179 to slip when a load exceeding a predetermined level is applied when the gear 307 rotates in the opposite direction. It's getting old. Further, when the gear 307 rotates in the sheet conveyance direction, the spring clutches 309 and 315 cause the rotation shaft 179 and the arms 311 and 317 to slip when a load exceeding a predetermined value is applied, and when the gear 307 rotates in the sheet conveyance direction, the rotation shaft 179 and the arms 311 and 317 slip.
1,317 is fixed.

The feeding means 161 includes a rotating shaft 319 supported by arms 311 and 317 as shown in FIG.
21.

A pulley 323 is attached to the rotating shaft 319. This pulley 323 is drivingly connected to the pulley 313 by a belt 325.

The first separating means 165 includes three separating rollers 17 attached to a rotating shaft 175 as shown in FIG.
It has 7. These three separation rollers 177
are arranged alternately with the two feeding rollers 183, and overlap each other by a length L1 in a direction perpendicular to the sheet conveyance direction.

One end of the rotating shaft 175 is supported by a bearing 176,
A gear 178 with a one-way clutch is attached. This gear 178 transmits a driving force to the rotating shaft 175 when a drive motor M, which will be described later, rotates in the forward direction, and slips against the rotating shaft 175 when it rotates in the reverse direction.

The second feeding means 167 includes three feeding rollers 32 attached to a rotating shaft 327 as shown in FIG.
It has 9. These feeding rollers 329 are
As shown in FIG. 4, it is arranged at a different position from the feeding roller 183 in the conveying direction. That is, the feeding roller 18
The feed roller 3 is located at a position away from the front extension line of 3.
29 are provided.

One end of the rotating shaft 327 is supported by a bearing 328,
A gear 331 with a one-way clutch is attached. This gear 331 transmits a driving force to the rotation shaft 327 when the drive motor M rotates in the forward direction, and slips against the rotation shaft 327 when the drive motor M rotates in the reverse direction.

The second separating means 169 includes four separating rollers 335 attached to a rotating shaft 333. These four separation rollers 335 are arranged alternately with the three feeding rollers 329, and are provided so as to overlap each other by a length L2 in a direction perpendicular to the sheet conveyance direction. Note that L2 is larger than L1. Further, the four separation rollers 335 are arranged at different positions in the conveyance direction from the three separation rollers 177.

One end of the rotating shaft 333 is supported by a bearing 334,
A gear 336 with a one-way clutch is attached. This gear 336 transmits a driving force to the rotating shaft 333 when the drive motor M rotates in the forward direction, and slips against the rotating shaft 333 when the drive motor M rotates in the reverse direction.

The registration means 171 includes a registration roller 339 attached to a rotation shaft 337 as shown in FIGS. 2 and 4, and a registration roller 34 attached to a rotation shaft 341 and pressed against the registration roller 339.
3. Note that a gear 345 with a one-way clutch is attached to the rotating shaft 337. This gear 345 slips on the rotation shaft 337 when the drive motor M rotates forward, and transmits a driving force to the rotation shaft 337 when the drive motor M rotates in the reverse direction.

Gears 178, 307, 331, 336, 345
is a drive motor M via a transmission mechanism (not shown).
is connected to.

<Configuration of copying machine 3> As shown in FIG.
1 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 . Beyond the intake ports 41 and 51,
Registration rollers 55 and a conveyor belt 57 are provided to supply sheets 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.

Below the platen 77 is a slit illumination device 7.
9 is provided 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 an optical 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, and the paper feeding timing is adjusted by the registration roller 55.
The image is transferred onto the sheet P sent between.

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 discharged from a discharge port 97 with the visible image facing upward by a discharge roller 95, and is stored in a sheet storage device such as a sorter 99.

<Configuration of the automatic document feeder 75> 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 in the document tray 201 into one sheet and sends out the document. The document sent out from the separation and feeding section 203 is conveyed onto the platen 77 and set at the reference position.
A transport unit 205 that sends out from above, and a discharge unit 20 that reverses the document sent from this transport unit and discharges it.
7 and a storage tray 209 for accommodating the sheets discharged from the discharge section 207, and is attached to the rear surface of the copying machine 3 via a hinge so as to be openable and closable.

<Operation> 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.

In this state, when the back cover 27 is closed, the motor 33 is automatically driven and the roller 35 is
rotates and the hopper 29 rises. The seat pushes up the empty sensor lever 141 and the level sensor lever 143, and when both are turned on, it stops.

As a result, the drive motor M rotates forward, and the gear 3
Rotation of 07, 178, 331, 336 is rotation axis 1
79, 175, 327, 333, the feeding rollers 183, 329 rotate in the sheet conveyance direction, and the separation rollers 177, 335 rotate in the sheet repelling direction. Note that the rotating shaft 337 does not rotate because the one-way clutch of the gear 345 slips.

The rotation of the rotating shaft 179 causes the hard crawler 321 to rotate in the sheet conveyance direction via the pulley 313, belt 325, and pulley 323, and the arms 311 and 317 to rotate downward. Arm 3
11, 317 are rotated so that the hard crawler 321 contacts the seat, a load is applied to the arms 311, 317, the spring clutches 309, 315 slip, and the hard crawler 321 comes into contact with the seat with a constant force.

When the hard roller 321 comes into contact with the sheet, the sheet is fed out, and first a separation operation is performed by the feeding roller 183 and the separation roller 177. Then, a second separation operation is performed by the next feeding roller 329 and separation roller 335, and the sheet is transported.

When the leading edge of the sheet is detected by the sensor 173, the drive motor M stops after a predetermined time T. Here, the predetermined time T is set to a time sufficient for the leading edge of the sheet to contact the rolling contact portions of the registration rollers 339 and 343 after passing the sensor 173, and for the sheet to bend. Therefore, the leading ends of the bent sheets are aligned and the sheet is in a standby state.

On the other hand, the document tray 20 of the automatic document feeder 75
1 and presses a copy button (not shown), the document is separated into one sheet by the separating and feeding section 203 and sent out, and the document is set at a reference position on the platen 77 by the conveying section 205. 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 sheet supply command is issued from the copying machine 3, and the drive motor M rotates in reverse. For this reason, the gear 345,
Registration rollers 339 rotate in the conveying direction via a rotation shaft 337, and driven registration rollers 343
At the same time, the sheet in the standby state is sent out.

By the way, due to the reverse rotation of the gear 307, the arm 3
11,317 rotates upward, and the hard crawler 321
leaves the seat. When the rotating shaft 319 hits the stoppers 149, 151, the arms 311, 3
17 is prevented from rising and the spring clutch 30
A load is applied to the gear 307, causing the gear 307 to slip relative to the rotating shaft 179.

Further, the gears 178, 331, 336 also rotate in the reverse direction, but the one-way clutch slips and the rotating shafts 175, 327, 333 are not driven. However, as the sheet is sent out by the registration rollers 339 and 343, the feeding roller 18
3, 329 and separation rollers 177, 335 rotate as the sheet moves.

The sheets sent out by the registration rollers 339 and 343 are supplied into the copying machine 3. and,
When the rear end of the sheet is detected by the sensor 173, the drive motor M rotates forward and the next sheet is sent to the standby position by the above-described operation.

The images of the sheets thus supplied to the copying machine 3 are copied by the image forming section 58, and the sheets are supplied to a sorter 99, where they are sorted and stored.

Note that as sheets are fed from the sheet feeding device 5, the leading ends of the empty sensor lever 141 and the level sensor lever 143 go down, and the rear ends go up. This rise in the rear end causes the level sensor 14 to
7 is turned off, the empty sensor 145 is turned off. As a result, the motor 33 rotates and the hopper 29 is raised by a predetermined height.

When this operation is repeated and the sheet runs out, the level sensor lever 143 is pushed up by the hopper 29 and the empty sensor lever 141 enters the empty detection hole 101, so the empty sensor 145 turns off and the level sensor 14
7 turns on. Under this condition, the empty state of the sheet is detected and the hopper 29 is automatically lowered.

<Effects of Example> According to this example described above, the following effects can be obtained.

Feed roller 183 rotating in the sheet conveyance direction
and a separation roller 177 that rejects the sheet that follows the sheet conveyed by the feeding roller 183.
A feeding roller 329 that conveys the sheet being sent out while being separated by the feeding roller 183 and the separation roller 177, and a separation roller 335 that rejects the sheet that follows the sheet conveyed by the feeding roller 329 are provided. Primary separation feed rollers 183 (2) and separation rollers 177 (3)
The number of secondary separation feeding rollers 329 (3
Since the number of feed rollers 183 and separation rollers 17 is smaller than the number of separation rollers 335 (four),
7 is smaller than the resistance between the feeding roller 329 and separation roller 335, the sheet can be easily gripped, skew is less likely to occur during gripping, and the sheet can be held between the feeding roller 183 and separation roller 177. In the loaded state, the feed roller 329
Since the separation is performed by the separation roller 335, skew is difficult to occur even in secondary separation.

[Modified example]

Although one embodiment of the present invention has been described above,
The present invention is not limited to the above-mentioned embodiment, and for example, the following modifications are possible.

(1) In the embodiment described above, the sheet conveying device is applied to the sheet feeding device 5, but it can also be applied to the separation feeding section 203 of the automatic document feeding device 75.

(2) Although the separation rollers 177 and 335 are shown as the first and second separation means 165 and 169, they may be separated by a friction member such as a fixed rubber pad. Further, the feeding means 163, 167 and the separating means 177, 169 may be belts or the like. Furthermore, rollers, friction members, belts, etc. may be combined.

(3) In the above embodiment, a device that feeds sheets from the top paper is shown, but the present invention can also be applied to a device that feeds sheets from the bottom paper.

〔Effect of the invention〕

According to the sheet conveyance device of the present invention, in the sheet conveyance device that separates and conveys a plurality of sheets into one sheet, a plurality of first feeders are provided in a direction intersecting the sheet conveyance direction, and the first feeder conveys the sheets. a plurality of first separation means provided in a direction intersecting the sheet conveyance direction and for rejecting the sheet following the sheet conveyed by the first feeding means;
a plurality of second feeding means, which are provided in a direction intersecting the sheet conveyance direction, and convey the sheets separated and sent out by the first feeding means and the first separating means; a plurality of second separation means provided in a crossing direction and for rejecting sheets that follow sheets conveyed by the second feeding means, the first feeding means and the first separation means; are smaller than the respective numbers of the second feeding means and the second separating means, and the first feeding means, the first separating means, and the second feeding means The second separating means are arranged alternately and overlapped in opposite directions, and the amount of overlap between the first feeding means and the first separating means is adjusted to the amount of overlap between the second feeding means and the first separating means. Since the amount of overlap with the second separating means is smaller than the amount of overlap between the first feeding means and the first separating means, the resistance to the sheet in the conveying direction is greater between the first feeding means and the first separating means than between the second feeding means and the second separating means. The distance between the first feeding means and the first separating means is smaller, making it easier to hold the sheet between the first feeding means and the first separating means, making it difficult for skew to occur when holding the sheet between the first feeding means and the second separating means, and making it easier to hold the sheet between the first feeding means and the first separating means. Since the amount of overlap between the first feeding means and the first separating means is relatively larger than the amount of overlap between the first feeding means and the first separating means, the sheet becomes stiffer, improving both conveyance and separation performance, and improving the quality of the sheet. Improvement in the separation performance of the device is achieved without the need for

[Brief explanation of drawings]

1 to 6 are diagrams showing an embodiment of the present invention, in which 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 sorter; Figure 3 is a cross-sectional view showing the internal structure of the sheet feeding device as seen from the side, Figure 3 is a cross-sectional view showing the structure of the elevating device of the sheet feeding device, and Figure 4 is a cross-sectional view showing the internal structure of the sheet feeding device seen from above. cross section,
FIG. 5 is a diagram showing the structure of the first feeding means and the first separating means, and FIG. 6 is a diagram showing the structure of the second feeding means and the second separating means. DESCRIPTION OF SYMBOLS 1... Placing table, 3... Copying machine, 5... Sheet feeding device, 17... Sheet storage part, 19... Mounting part, 29... Hopper, 31... Lifting device, 41...
... Sheet intake port, 75 ... Automatic document feeder, 99 ... Sorter, 161 ... Feeding means,
163...first feeding means, 165...first separation means, 167...second feeding means, 169...
Second separation means, 171...Resist means, 17
3...Sensor.

Claims (1)

[Scope of Claims] 1. A sheet conveyance device that separates and conveys a plurality of sheets into one sheet, comprising: a plurality of first supply means that are provided in a direction intersecting the sheet conveyance direction and convey the sheets; a plurality of first separating means provided in a direction intersecting the conveying direction of the sheet and for rejecting the sheet following the sheet conveyed by the first feeding means; a plurality of first separating means provided in the direction intersecting the sheet conveying direction; a second feeding unit that transports the sheet separated by the first feeding unit and the first separation unit; a second separating means for rejecting the sheet following the sheet conveyed by the feeding means, and the number of each of the first feeding means and the first separating means is adjusted to smaller than each number of second separating means, and the first feeding means and the first separating means, and the second feeding means and the second separating means are arranged alternately, respectively, and overlap in opposite directions, and the amount of overlap between the first feeding means and the first separating means is smaller than the amount of overlap between the second feeding means and the second separating means. A sheet conveying device characterized by: