JPH06144683A - Sheet storage device for image forming device - Google Patents

Abstract

PURPOSE:To enable the compact storage of large-size sheets in a relatively small space by dividing the storage place of sheets, discharged at the specified speed from an image forming device, according to large size and smaller sizes. CONSTITUTION:A sheet storage device B provided adjacently to the paper discharge port 8 of an image forming device A is provided with a hanger part 25 for supporting large-size sheets in the state of being bent in approximately inverted U-shape in the sheet discharge direction, a tray 16 for stacking small- size sheets in the sheet discharge direction, and a flapper 12 disposed in sheet carrier paths 13, 14, provided among the hanger part 25, the tray 16 and the discharge port 8 so as to switch the sheet discharge direction either to the hanger part 25 or tray 16 according to the sheet size.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a storage device for printed sheets in an image forming apparatus such as a copying machine, a printer or a plotter.

[0002]

2. Description of the Related Art Generally, in this type of apparatus, a tray for sequentially stacking and storing sheets of paper is extended at a sheet discharge port of an image forming apparatus, and sheets fed from the sheet discharge port are stacked and stored on the tray. Is widely known. Further, there is known a sorter device in which a plurality of sheet storage trays are provided at the top and bottom to sort sheets from a sheet discharge port in page order.

[0003]

However, since all of the conventional storage devices stack and store paper in a substantially flat tray provided at the paper discharge port, the image forming apparatus displays images on large-size paper. There is no choice but to increase the size of the storage device when forming. For example, Japanese Industrial Standard A0
Taking a plotter for forming an image on a sheet such as a plate, an A1 plate, and an A2 plate as an example, a storage device for these sheets has a drawback that it becomes an inconvenient device that does not fit the actual situation that requires an extremely large installation area.

In view of the above drawbacks, the present invention has been made based on the knowledge that large size sheets of a predetermined size or larger are folded and stored in a U shape. That is, the object of the present invention is to
It is possible to store the paper discharged from the image forming apparatus by dividing it into large plate sizes and sizes smaller than that.
An object of the present invention is to provide a paper storage device that can be stored in a compact space in a relatively small space.

Another object of the present invention is to provide a sheet storage device which can be attached to the sheet discharge ports of various image forming apparatuses and can surely bend and store sheets discharged at various speeds. In offer.

[0006]

In order to achieve the above object, a sheet storage device according to the present invention is provided adjacent to a sheet discharge port of an image forming apparatus such as a copying machine, a printer or a plotter, and is discharged from the sheet discharge port. In a paper accommodating device for sequentially stacking and accommodating sheets of paper, a hanger portion for bending and supporting the paper sheets in a substantially inverted U shape in the paper ejection direction, a tray portion for accumulating and placing the paper sheets in the paper ejection direction, and these hanger portions And a gate unit arranged between the tray unit and the sheet discharge port, and a gate unit for switching the sheet discharge direction to one of the hanger unit and the tray unit according to the size of the sheet.

[0007]

According to the above-mentioned means, the gate portion is switched according to the size of the sheet fed out from the sheet discharge port, and in the normal use state, the small plate size sheet has the transport path to the tray section selected, and the large plate is selected. For the size of paper, the transport path to the hanger is selected. Therefore, a large-size sheet of paper whose transport path to the hanger section has been selected enters one side of the hanger section from the leading edge, and when the sheet reaches the predetermined length, the paper ejection posture direction is displaced to the other side of the hanger section. The rear end side of the paper is sent to the other side of the hanger portion, and thus the large-size paper discharged from the paper discharge port is bent and supported by the hanger portion to be compactly stored in a substantially inverted U shape. You can

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 shows a case where the present invention is applied to an image forming apparatus A including a raster plotter. The sheet storage device B, which is a unit separate from the image forming apparatus A, is attached to the sheet discharge port of the image forming apparatus A.

The image forming apparatus A shown in FIG. 2 shows a thermal plotter as an example, in which a roll-shaped thermal paper 1 is wound around a drum 2 and stored. The thermal paper 1 is cut by the cutter means 3 into a predetermined length. Reference numeral 4 denotes a pair of conveyance rollers, which feed the roll-shaped thermal paper 1 and convey it to the printing point. The platen 5 is prepared at the printing point, and the heating head 6 is provided in pressure contact with the platen 5. Then, the sheet printed by the heating head 6 is discharged from the sheet discharge port 8 by the sheet discharge roller 7 at a predetermined speed. Reference numeral 9 is a stand of the image forming apparatus A that supports the above-described image forming unit.

The conventional thermal plotter as described above is
The feed roller 4 for feeding the roll-shaped thermal paper 1, the roll platen 5, and the paper discharge roller 7 are connected to a drive motor (not shown) so as to feed the paper so that the paper is fed at a predetermined speed synchronized with each other. Has been done. An application controller is electrically connected to the heating head 6 to convert a drawing command such as a computer into raster data and perform thermal printing in synchronization with the sheet speed of the platen 5 part.

The image forming apparatus A described above is a well-known thermal plotter, but in the present invention, an electrophotographic image forming apparatus may be used instead. In this case, the electrophotographic image forming apparatus forms an image on a photoconductor by a laser scanning unit or an LED light emitting unit known as an optical printer, electrically attaches toner ink to the image, and develops the image. The structure of an ordinary optical printer, in which an image is transferred onto a sheet and then fixed, may be adopted. It is also known that the electrostatic image forming apparatus uses static electricity that the paper itself is sensitive to static electricity, forms an image on the paper surface with an electrostatic head, and then adheres and develops toner ink to fix it. However, the present invention can be adopted.

A paper storage device B is attached adjacent to the paper discharge port 8 of the image forming apparatus A as described below.

The sheet storage device B is provided with a receiving port 11 connected to the sheet discharging port 8. Behind the receiving port 11, a flapper 1 serving as a gate portion which can be switched in two directions.
2 are provided, and by switching the flapper 12, two different paper transport paths 13 following the flapper 12,
14 can be selected as an alternative. One of the paper transport paths 13 is a path for storing small size paper,
A path extending from the receiving port 11 in a substantially horizontal direction is formed, and a tray 16 is arranged at the lower rear of the discharge roller 15. This tray 16 is, as shown in FIG.
It is configured by arranging a plurality of linear members in the lateral direction, and stacks and stacks sheets of paper cut into, for example, A3 size or smaller. The other paper transport path 14 is a path for storing large-size paper, and the flapper 1
A path extending in the substantially vertical direction is formed by turning the direction immediately downward from 2, and the discharge roller 20 is provided in the middle of the path.
Guide member 21, shift member 22, pair of holding portions 2
3, 24 are arranged in this order, and a hanger portion 25 is arranged below them.

The respective discharge rollers 15 and 20 provided in the paper conveying paths 13 and 14 are rotationally driven by a motor M capable of rotating in the forward and reverse directions. That is, each discharge roller 1
Belts 26, 2 are provided between the motors 5, 20 and the motor M, respectively.
7 is bridged, and by the action of a clutch mechanism (not shown) provided on the main shaft of the motor M, only one discharge roller 15 is in the forward direction (counterclockwise direction in FIG. 2) when the motor M rotates in the forward direction. ), And when the motor M rotates in the reverse direction, only the other discharge roller 20 rotates in the reverse direction (clockwise direction in FIG. 2). Further, in this embodiment, each of the discharge rollers 15 and 20 and the flapper 1 are
Belts (not shown) are also provided between the two rotating shafts 28.
The flapper 12 is also rotated around the rotation shaft 28 in association with the rotation of the discharge rollers 15 and 20, and the paper transport paths 13 and 14 are automatically switched. Moreover, in this embodiment, a pair of stopper members (not shown) for restricting the rotation amount of the flapper 12 when switching the flapper 12 are provided at positions near the top and bottom of the flapper 12, respectively, and a torque limiter ( (Not shown) is provided, and when the flapper 12 hits the stopper member and its rotation is restricted, the rotation shaft 28 is caused to rotate by the action of the torque limiter. In addition,
In this embodiment, when the motor M is stopped, the flapper 12 holds the switching state immediately before that.

Thus, in this embodiment, the flapper 12
Since the switching is performed in conjunction with the rotation of the discharge rollers 15 and 20, a solenoid generally used as a switching unit is not required, and a switching direction determination circuit, a switching timing determination circuit, etc. Is also unnecessary.

The discharge roller 20 disposed in the large-size sheet conveying path 14 includes a pair of rollers 20a and 20a.
One roller 20a is connected to the motor M via a torque limiter, and a rotary encoder is attached to the other roller 20b driven by the roller 20a. In this embodiment, the peripheral velocity V1 of the discharge roller 20 is set to the discharge roller 7 of the image forming apparatus A.
Is set slightly faster than the peripheral speed V2 (for example, about 10%). As a result, when the discharged sheet is constrained by both the sheet discharge roller 7 and the sheet discharge roller 20, the roller 20a slips due to the action of the torque limiter, and the sheet discharge roller 20a and the sheet discharge roller 20b accompanying it are decelerated. Then, by changing to the peripheral speed V2 of the paper discharge roller 7, the paper is carried at the speed of the carrying roller 7.

The leading edge of the sheet is detected by detecting the change when the peripheral speed of the discharge roller 20 is reduced from V1 to V2 by the rotary encoder. After the leading edge is detected, the rotary encoder counts the number of rotations of the discharge roller 20, and when the number of pulses is counted up to a preset number of pulses, it is detected from the rotary encoder that the substantially central portion of the paper has reached a predetermined position. Give a signal. The number of set pulses counted by the rotary encoder differs depending on the paper size.
When a paper size signal is sent from the paper storage device B
The above-mentioned operation is performed by selecting the set value according to the size on the side.

Directly behind the discharge roller 20, a guide member 21 and a shift member 22 are arranged so as to face each other with the sheet conveying path 14 interposed therebetween. These members 21, 22
Are arranged with an appropriate inclination angle and are connected by a connecting member 41. In addition, the shift member 22
By pivotally supporting the rotary shaft 42 provided at the upper end of the rotary shaft 42 on the frame frame of the sheet storage device B, the guide member 21 becomes integrated when the shift member 22 swings around the rotary shaft 42. Rock. The guide member 21 is the discharge roller 2
It is for guiding the paper fed from 0 to one side of a hanger portion 25 described later, and is inclined downward to the right in FIG. Further, when the sheet is guided to one side of the hanger portion 25 by the guide member 21 to the substantially central portion, the shift member 22 swings to the left side in FIG. It is for leading the paper to the other side of 25.

The hanger portion 25 is arranged near the lower portions of the guide member 21 and the shift member 22, and has a substantially inverted U-shaped cross-section with a support upper surface formed in a curved shape. The hanger portion 25 extends in the left-right direction in the cross-sectional shape described above, and one end portion or both end portions thereof are attached to the frame body frame of the sheet storage device B. Since the hanger portion 25 according to this embodiment has a substantially inverted U-shaped cross section and does not extend downward, when the paper is suspended,
The hanging end of the paper does not interfere with the hanger 25. Therefore, even if a large number of sheets with curled edges are accumulated, the edges of the sheets do not bulge and the sheets can be smoothly accumulated. The cross-sectional shape of the hanger portion 25 is not limited to the above-mentioned substantially inverted U-shape, but can be appropriately selected, for example, a mountain fold shape or a semi-elliptical shape.

The hanger portion 25 and the guide member 21 described above.
A pair of hold portions 23 and 24 are provided between the shift member 22 and the shift member 22 so as to hold the sheet suspended and placed on the hanger portion 25 so as not to slip off.
These holding parts 23 and 24 respectively have a rotating shaft 4
5 and 46 are arm members that swing about the retracted position where neither of them interferes with the sheet entering the hanger portion 25, and the hold position for pressing the support surface of the hanger portion 25. Rocks between. A rubber piece 47 is fixed to the tip of one of the hold portions 23, and the paper is held by bringing the rubber piece 47 into contact with a position slightly lower than the curved portion of the hanger portion 25. The other holding section 24 has a tip of an arm formed by a rubber roller 48, and abuts against the curved section on the other side of the hanger section 25 to hold the sheet.

Since the pair of hold portions 23 and 24 alternately occupy the retracted position and the hold position and one of them holds the paper without fail, the hanger portion 25 does not matter how much the paper is accumulated. The paper can be prevented from slipping off. The operation timings of the holding portions 23 and 24 are the same as those of the guide member 21 and the shift member 22.
Is controlled between.

Next, the operation of the sheet storage device B having the above structure will be described with reference to FIGS. First, a size signal of a sheet discharged from the image forming apparatus A and a sheet discharge instruction signal are sent to the sheet storage apparatus B. In the sheet storage device B, the motor M receives this and rotates in either the forward or reverse direction. For example, if there is a signal for large size paper,
The motor M rotates in the opposite direction, and the discharge roller 20 rotates in the clockwise direction in conjunction with this. Then, the flapper 12 is further interlocked and switched to the sheet conveyance path 14 side. At this time, the guide member 21, the shift member 22, and the holding portions 23 and 24 are set in the state shown in FIG.

The sheet carried out from the sheet discharge port 8 of the image forming apparatus A to the receiving port 11 of the sheet storage apparatus B is carried into the large plate size side sheet carrying path 14 selected by the flapper 12. The speed at which the sheet is conveyed at this time depends on the peripheral speed V2 of the sheet discharge roller 7 of the image forming apparatus A. However, since the sheet conveying path 14 extends in the substantially vertical direction, the leading edge of the sheet is weighed by its own weight. With the help, the sheet is smoothly guided downward in the sheet conveyance path 14. On the other hand, when the leading edge of the sheet is nipped by the discharge roller 20, the sheet is pulled by the discharge roller 20 due to the speed difference between the discharge roller 7 and the discharge roller 20, but slippage occurs in the torque limiter, so the discharge roller 20 slows down. In synchronism with the peripheral velocity V2 of the paper discharge roller 7. The deceleration change at this time is detected as the number of pulses generated by the rotary encoder is reduced, and the arrival of the leading edge of the paper at the discharge roller 20 is detected. Further, thereafter, the rotary encoder counts a predetermined number of pulses to recognize that the paper has reached a predetermined central portion.

The image forming apparatus A may be replaced by the above method.
Receives the paper discharge speed information and the paper size information as electrical signals, arranges a leading edge detection sensor of the sheet near the upper side of the discharge roller 20, and activates the timer means by the signal from the leading edge detection sensor. It is also possible to calculate that the paper has reached a predetermined central portion.

The leading end of the sheet that has passed through the discharge roller 20 is guided along the guide member 21 to the front side of the hanger 25 in the transport direction. Then, at the time when the sheet enters the side of the arrow a shown in FIG. 3A for a predetermined length and the substantially central portion of the sheet reaches the position of the discharge roller 20, the motor M is momentarily stopped and the discharge roller 20 moves. Stop spinning.

Since the sheet is not conveyed on the leading end side due to the stop of the discharging roller 20, the trailing end side of the sheet fed by the rotation of the discharging roller 7 is the sheet conveying path 1.
However, at this time, the guide roller 49 provided in the middle of the sheet conveying path 14 escapes backward as shown by the phantom line in FIG. Allows the paper to form a loop.

Next, in this state, the guide member 2
1 and the shift member 22 swing from the guide position shown in FIG. 3 (A) in the direction of arrow c, and move to the shift position shown in FIG. 3 (B). Therefore, the sheet is pressed by the lower end portion of the shift member 22 in a substantially doglegged shape.
Since the sheet guided to the one side of the sheet 5 is not held by the holding unit 23 and is free, the leading end side of the sheet is slightly pulled back. Then, in that state, the hold unit 23
The rubber piece 47 presses the hanger portion 25 to hold the sheet. Almost at the same time as the holding portion 23 presses one side of the hanger portion 25, the holding portion 24 on the other side is held by the hanger portion 25.
The holding on the other side is released and starts to separate from the hanger portion 25. Further, when the motor M is rotated at the same time, the paper is fed again by the discharge roller 20. The ejected direction of the fed-out sheet is changed by the guide of the shift member 22, the holding section 24 in the middle of returning to the retracted position also assists the loop formation, and the holding section 23 holds the leading edge side of the sheet. As shown in FIG. 3 (C), the fed paper passes over the hanger portion 25 while drawing a loop on the other side of the hanger portion 25, is guided along the other side, and When the edge comes off the discharge roller 20, the paper falls by its own weight to the other side of the hanger portion 25 shown by the arrow b, and is suspended and held in the hanger portion 25 in a substantially inverted U shape. In addition, the series of operations described above, that is, the movement of the guide member 21, the shift member 22, and the hold portion 23 from the stop of the discharge roller 20, and the discharge roller.
The restart of the printer 20 and the operation of the hold unit 24 are executed in a relatively short time.

In this embodiment, the shift member 22 is moved before the front end side of the paper is held by the hold unit 23, but this is held by both the discharge roller 20 and the hold unit 23 first. This is because the margin length of the paper required for shifting the paper cannot be obtained, and the paper may be damaged when the shift member 22 is moved. In the above embodiment, the shift member 22 is moved while the feeding of the sheet from the discharge roller 20 is stopped, but the shift member 22 can be moved in the state of continuously feeding the discharge roller 20 and the sheet. Is.

When the trailing edge of the sheet comes off the discharge roller 20, the guide member 21, the shift member 22, and the holding portions 23 and 24 are swung to the opposite side at the same time or with a slight delay, the original state is maintained. Return to position. Therefore, the holding unit 24 holds the sheet again. After the paper is completely discharged, the paper hung in the inverted U shape on the hanger portion 25 from the discharge side can be pulled out obliquely downward to be easily collected.

On the other hand, when a small-sized sheet is discharged from the image forming apparatus A, the motor M rotates in the forward direction as shown in FIG. While rotating in the direction, the flapper 12 is interlocked and is switched to the sheet conveyance path 13 side. Then, the paper carried out from the paper exit 8 of the image forming apparatus A to the receiving entrance 11 of the paper storage device B is carried into the paper carrying path 13 on the small plate size side selected by the flapper 12, and the paper ejecting roller 15 Is discharged onto the tray 16.

[0031]

As described above, according to the sheet storage device of the image forming apparatus of the present invention, since the gate portion for switching the sheet conveying path according to the size of the sheet discharged from the image forming apparatus is provided. The gate can set the storage location for large-size paper separately from that for small-size paper, and facilitates paper recovery.
Further, by switching the gates in tandem with the paper transport driving means provided in the respective paper transport paths, a solenoid for switching the gates, a discrimination circuit for selecting the switching direction, etc. No longer needed
Etc. are effective.

[Brief description of drawings]

FIG. 1 is a perspective explanatory view in which a sheet storage device according to the present invention is connected to a plotter.

FIG. 2 is a cross-sectional explanatory diagram of a sheet storage device according to the present invention.

FIG. 3 is an explanatory diagram showing an operating state when a large-sized sheet is stored.

FIG. 4 is an explanatory diagram showing an operating state when a small-sized sheet is stored.

[Explanation of symbols]

 A image forming device B paper storage device 8 paper discharge port 12 flapper (gate part) 13 paper transport path 14 paper transport path 16 tray 25 hanger part

Claims (5)

[Claims] 1. A paper storage device adjacent to a paper exit of an image forming apparatus such as a copying machine, a printer, or a plotter, for sequentially stacking and storing paper discharged from the paper exit, in a paper discharge direction. A hanger portion that bends and supports the inverted U shape, a tray portion that stacks and stacks sheets in the sheet discharge direction, and a sheet conveyance path that is provided between the hanger portion and the tray portion and the sheet discharge port. A sheet storage device in an image forming apparatus, which is provided with a hanger portion and a gate portion that switches a sheet discharge direction on one side of a tray portion according to a sheet size. 2. The hanger portion supports sheets of a predetermined size or more that are preset by bending them in a substantially inverted U shape in the sheet discharge direction, and the tray portion stacks sheets of the predetermined size or smaller in the sheet discharge direction. The sheet storage device in the image forming apparatus according to claim 1, wherein the sheet storage device is placed. 3. The hanger portion is arranged between the image forming apparatus and the tray portion, and further below the conveying path for conveying the sheet from the discharge port of the image forming apparatus to the tray portion,
2. The sheet storage device in an image forming apparatus according to claim 1, wherein a sheet transporting path from the gate portion to the hanger portion extends in a substantially vertical direction. 4. A sheet storage device in an image forming apparatus according to claim 1, wherein a sheet transporting path from the gate portion to the hanger portion extends in a substantially vertical direction. 5. The gate unit comprises a sheet conveying unit provided in a sheet conveying route from the gate unit to the hanger unit, and a driving unit of the sheet conveying unit provided in a sheet conveying route from the gate unit to the tray unit. 3. The sheet storage device in the image forming apparatus according to claim 1, wherein the sheet storage device is switched in conjunction with.