JP2000016680A - Discharge paper sheet sorting device and picture image formation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid a condition in which ink of a paper sheet discharged on a paper sheet discharge base before the paper sheet to be sorted adheres on a rear surface of the discharged paper sheet to be sorted. SOLUTION: At the time of sorting printing mode setting, a paper sheet Sa to be sorted is shifted in the direction of sorting by a pick up 25 when the paper sheet Sa to be sorted is discharged on a paper sheet discharge base 7. In this case, it is possible to avoid a condition in which ink of a paper sheet S discharged on the paper sheet discharge base 7 before the paper sheet Sa to be sorted adheres on a rear surface of the discharged paper sheet Sa to be sorted by changing the wait time from the time when the paper sheet Sa to be sorted is discharged up to the time when a roller 27 of the pick up 25 is driven in accordance with a dry condition of a printed picture image.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper discharge sorting apparatus for sorting printed sheets and an image forming apparatus such as a printing machine or a copying machine.

[0002]

2. Description of the Related Art For example, Japanese Patent Laid-Open Publication No.
There is a “paper discharge stacker device” described in Japanese Patent No. 01615. This paper discharge stacker device reciprocates a paper discharge tray on which paper is stacked in the width direction of the paper every time a predetermined number of papers are discharged, so that the discharged paper is width-width-set by the set number of papers. In this way, the printed material is sorted in each sorting group. further,
Some paper discharge sorting apparatuses aiming at the same effect as above do not move the paper discharge table but change the paper discharge position every time a set number of papers are discharged.

[0003] Further, in an apparatus having an effect similar to that of the above-mentioned sheet discharge stacker, the sheet discharge table is not reciprocated in the width direction, but is a "sorting apparatus" described in Japanese Patent Publication No. 6-78151. In some cases, the discharge tray on which sheets are stacked is rotated by 90 degrees every time a set number of sheets are discharged. By changing the direction of the paper discharge tray, the sheets stacked on the paper discharge tray are alternately stacked every set number of sheets.

Further, in a general office printing machine such as a stencil printing machine, jump plates are provided on both sides of a paper transport unit so as to protrude the side edges of the paper. The paper is bent so as to bend downward in a U-shape with respect to the part, and the paper is made to have a waist, both sides of the discharged paper are supported by two side fences, and the paper is bent into a U shape and stored. There is a discharged paper stacking device. As such a paper output stacking apparatus, the above-described paper stack in which the papers are shifted in the width direction cannot be used. The work of placing the marking tape on paper has been repeated.

[0005] Alternatively, there is a "tape launcher for printing press" described in Japanese Patent Application Laid-Open No. 7-1722, which automates the above-mentioned sorting operation using a tape. In this method, a tape on which information on the sorting status and the like is printed is sent out each time a set number of sheets are discharged, and the tape is inserted for each set number of sheets.

Further, there is a sorter device which divides the sheets discharged from the image forming apparatus into a plurality of discharge trays for each set number of sheets, and sorts the sheets for each discharge tray.

In the above-described paper discharge stacker, which stacks papers while shifting them in the width direction, when the paper discharge table is moved and stopped, the overlapped papers move by inertia, so that the papers are sorted. The boundaries may not be clear. In the case of the above-described "sorting device" in which the paper discharge tray is rotated by 90 degrees, the length of any side of the paper discharge tray must be longer than the length of a predetermined sheet in the longitudinal direction. However, the size increases and the weight increases. In addition, since the paper discharge table is rotated, the configuration becomes complicated and expensive. Further, these devices cannot be used for a device that guides both sides of a sheet and stacks it in a U-shape in order to make the sheet to be ejected stiff.

[0008] In the case of stacking paper in a U-shape, not only the work of placing the mark tape on the paper but also the work of removing it is necessary, which is inefficient. In addition, the tape may come off, resulting in incomplete sorting. Furthermore, tapes are uneconomic because they are difficult to reuse. The above "tape launcher for printing press" that automatically sorts by tape
However, since the timing of feeding the tape and the timing of discharging the paper may not be synchronized, smooth and reliable sorting cannot always be realized, resulting in poor reliability. Then, an operation for removing the tape is required, which is also inefficient.

Further, instead of the above-mentioned mark tape,
While printing is temporarily stopped, one blank sheet is ejected and used as a mark for the boundary of the sorting group. However, when the printed matter is a solid image, the contrast difference is clear. Therefore, it is easy to discriminate, but it is difficult to discriminate a printed matter having a small image area because the contrast difference is small.

A sorter apparatus for sorting into a plurality of paper discharge trays is large and expensive, and is often separated from the image forming apparatus and treated as an option. Further, it requires an occupied area equivalent to that of an image forming apparatus, and has not been widely adopted for general office use.

[0011]

SUMMARY OF THE INVENTION
When stacking sheets for each sorting group on the paper output tray, the edge of the uppermost sheet of the sorting group is held by a pickup and shifted in the horizontal direction, and the shifted sheet is used as a sorting mark of the sorting group. A paper discharge sorting device has been proposed.

However, when the uppermost sheet of the sorting group is displaced, the ink of the next sheet is rubbed by the uppermost sheet, so that the image of the next sheet is disturbed and the back of the uppermost sheet is disturbed. There is a problem that the ink of the next layer adheres and stains. Such a thing, when the image amount is large like a solid image, in a low temperature environment where the fluidity of the ink is poor, when the drying of the ink is delayed due to the high printing speed,
This is particularly likely to occur when the printing speed is low and the amount of ink transfer is large, or when a sheet of paper having poor ink absorbency such as high quality paper with high smoothness is used.

Conversely, when the image amount is small, in a high-temperature environment, when the printing speed is slow, and it is determined that the ink on the paper that has already been printed is dry, the printing speed is high. When the transfer amount is small, when using paper with high ink absorbency such as loose paper, etc.
Since it is not possible to shorten the time from when the paper to be sorted is discharged to when the sorting operation is performed, there is a problem that the printing cycle becomes long.

[0014]

According to a first aspect of the present invention, there is provided a paper output sorting apparatus, comprising: a paper output table on which printed sheets sequentially discharged and dropped from an image forming apparatus are stacked; A pickup that is driven by a pickup drive unit to shift the sheet to be discharged in the sorting direction when the sheet to be sorted is discharged from the forming apparatus;
A time changing unit configured to change a waiting time from when the paper to be sorted from the image forming apparatus is discharged to when the pickup driving unit is driven.

Therefore, it is possible to shift the paper to be sorted in the sorting direction at a time corresponding to the dry state of the printed image of the paper overlapping the lower side of the paper to be sorted.

According to a second aspect of the present invention, there is provided an image forming apparatus comprising: a printing unit; an image amount detecting unit for detecting an amount of an image to be printed on a sheet; Output means for outputting to the time changing means of the paper discharge sorting apparatus a command to change the waiting time from when the paper to be sorted is discharged to the paper discharge tray to when the pickup drive unit is driven. Have.

Therefore, the waiting time from when the paper to be sorted is discharged to the paper discharge tray to when the pickup driving unit is driven is determined according to the image amount. This allows
It is possible to shift the paper to be sorted in the sorting direction at a time corresponding to the dry state of the print image of the paper that overlaps below the paper to be sorted.

According to a third aspect of the present invention, there is provided an image forming apparatus comprising: a printing unit; a paper setting unit for designating a type of paper; a paper discharge sorting device according to the first aspect; Output means for outputting to the time changing means of the paper discharge sorting apparatus a command to change the waiting time from when the paper to be ejected to the paper discharge tray to when the pickup drive section is driven. .

Therefore, the waiting time from when the paper to be sorted is discharged to the paper discharge tray to when the pickup driving unit is driven is determined according to the type of the specified paper. This makes it possible to shift the paper to be sorted in the sorting direction at a time corresponding to the dry state of the print image of the paper that overlaps below the paper to be sorted.

According to a fourth aspect of the present invention, there is provided an image forming apparatus, comprising: a printing section; a temperature detecting means for detecting a temperature; a sheet discharge sorting apparatus according to the first aspect; Output means for outputting a command to change the waiting time from when the paper is discharged to the paper tray to when the pickup drive unit is driven to the time changing means of the paper discharge sorting device.

Therefore, the waiting time from when the paper to be sorted is discharged to the paper discharge tray to when the pickup driving unit is driven is determined according to the detected temperature. This makes it possible to shift the paper to be sorted in the sorting direction at a time corresponding to the dry state of the print image of the paper that overlaps below the paper to be sorted.

According to a fifth aspect of the present invention, there is provided an image forming apparatus, comprising: a printing unit; a printing speed setting means for setting a printing speed;
And a command to change a waiting time from a timing at which sheets to be sorted according to a set print speed are discharged to the discharge to a time at which the pickup driving unit is driven is described. Output means for outputting to the time changing means of the paper discharge sorting device.

Therefore, the waiting time from when the paper to be sorted is discharged to the paper discharge tray to when the pickup driving unit is driven is determined according to the set printing speed.
This makes it possible to shift the paper to be sorted in the sorting direction at a time corresponding to the dry state of the print image of the paper that overlaps below the paper to be sorted.

[0024]

FIG. 1 shows a first embodiment of the present invention.
This will be described with reference to FIG. First, an example of an image forming apparatus on which the sorting apparatus of the present invention is mounted will be schematically described with reference to FIG. The image forming apparatus in this example is a stencil printing apparatus, but is not limited to this.

A plate cylinder 2 around which a master 1 having been made is wound is provided rotatably. Around the plate cylinder 2, a master 1 is heated and pierced to make a plate, and a plate making section 3 for feeding the master 1 to the plate cylinder 2 and a sheet S fed from a sheet feeding section (not shown). A pair of registration rollers 4 for transporting the master 1 wound around the plate cylinder 2 in a timely manner and a press roller 5 for pressing the sheet S fed from the registration rollers 4 to the plate cylinder 2 via the master 1; A peeling claw 6 for peeling the printed paper S from the plate cylinder 2 and a paper discharge table 7 for loading the paper S peeled by the peeling claw 6 are arranged.

The plate making section 3 includes a platen 9 that is driven to rotate along a transport path 8 of the master 1, a thermal head 10 that is supported so as to be able to contact and separate from the platen 9, and a master 1.
Is formed by sequentially disposing a fixed blade 11 and a movable blade 12 for cutting the sheet, a pair of conveying rollers 13 and 14, a guide plate 15 for supporting the master 1 from below, and the like. The roll core 1a of the master 1, the platen 9, the transport rollers 13, 14 and the like are rotatably supported by a side plate (not shown) of a main body case of the stencil printing apparatus.

The plate cylinder 2 has a non-opening 2a and an opening 2b. The opening 2b is provided with a mesh screen formed of a resin or metal net. The plate cylinder 2 has flanges (not shown) fixed to both ends thereof rotatably supported by an ink pipe 16 fixedly supported on a side plate of the stencil printing apparatus, and is driven clockwise. Inside the plate cylinder 2, an ink roller 17 and a doctor roller 1 which come into contact with the inner peripheral surface of the plate cylinder 2 are provided.
8 are rotatably provided with a slight gap therebetween. A supply hole 1 formed at the lower end of the ink pipe 16 is formed in a wedge-shaped space between the ink roller 17 and the doctor roller 18.
An ink reservoir 20 for receiving ink dropped from the ink reservoir 9 is formed. Ink is supplied to the ink pipe 16 from an ink pack (not shown) provided outside the plate cylinder 2. A stage 21 and a clamper 22 for holding the leading end of the master 1 at the non-opening portion 2a are attached to the outer peripheral surface of the plate cylinder 2. The stage 21 is formed of a magnetic material and has a length along the axial direction of the plate cylinder 2. The clamper 22 is rotatably supported by a clamper shaft 23 disposed along the longitudinal direction of the stage 21 as a fulcrum.

Here, the plate cylinder 2, the press roller 5, the ink roller 17 incorporated in the plate cylinder 2, and the doctor roller 18 constitute a printing section P.

Next, the operation of the stencil printing apparatus will be described. When a document is set on a document reading unit (not shown) and a start signal is issued by pressing a start button, an image of the document is read by the document reading unit,
The plate cylinder 2 is driven counterclockwise by a motor (not shown). In this process, the master 1 which has been wound on the plate cylinder 2 is peeled off by a plate discharging device (not shown) and discarded, and the plate cylinder 2 is stopped when the clamper 22 reaches almost directly above. . At the time of this stop, the clamper 22 rotates in the opening direction about the clamper shaft 23 and is maintained in the plate feeding standby state.

When the image data is output to the thermal head 10, dots are formed on the master 1 by punching based on the image data. The master 1 is transported toward the plate cylinder 2 by rotation of the platen 9 and the transport rollers 13 and 14. At this time, when it is determined that the leading end of the master 1 has reached the clamper 22 by counting the number of steps of the stepping motor that drives the platen 9 and the transport rollers 13 and 14, the clamper 22 is closed by an opening / closing device (not shown). The tip of the master 1 is clamped between the clamper 22 and the stage 21 on the plate cylinder 2. Subsequently, plate cylinder 2 is master 1
The master 1 is wound around the outer circumference of the plate cylinder 2 by being driven clockwise at a peripheral speed substantially equal to the transport speed of the master 1. Then, when it is determined from the number of steps of the stepping motor that plate making is completed, the movable blade 12 is operated to cut the master 1, and the platen 9 and the transport rollers 13, 14 are stopped. When the plate cylinder 2 further rotates, the winding of the master 1 around the plate cylinder 2 is completed.

As described above, when the winding of the master 1 around the plate cylinder 2 is completed, the sheets S stacked on a sheet feeding tray (not shown) are fed by a separation sheet feeding device (not shown).
The sheet S is conveyed between the plate cylinder 2 and the press roller 5 by the registration roller 4 which rotates in synchronization with the rotation of the plate cylinder 2. When printing, the paper S is pressed by the press roller 5.
Is pressed against the outer periphery of the plate cylinder 2. As a result, the ink oozes out from the perforations of the master 1 and is transferred to the sheet S. That is, printing is performed.

Next, the configuration of the paper discharge sorting device A for sorting the paper S printed by the stencil printing apparatus will be described. The paper output tray 7 has an end plate 7a
Has a partition plate 7b on the side opposite to the discharge direction, and the interval between the end plate 7a and the partition plate 7b is slightly larger than the size of the paper S to be used. Reference numeral 24 denotes a paper transport unit that transports the printed paper S toward the paper discharge tray 7. A pickup 25 is provided below the paper transport unit 24. The pickup 25 has a swing arm 26 rotatably supported, and a roller 27 rotatably supported at a free end of the swing arm 26. Swing arm 26
Is driven by an arm drive motor 29 that can rotate forward and backward together with a shaft 28 fixed to the lower end thereof, and a roller 27 is driven by a roller drive motor 30 fixed to the free end of the swing arm 26.
(Pickup drive unit) (see FIG. 2).

Therefore, the swing arm 26 rotates to the area within the projection area of the sheet discharge table 7 by driving the arm drive motor 29 in the counterclockwise direction, and the arm drive motor 2
By driving the sheet 9 clockwise, the sheet 9 rotates outward from the area within the projection area of the sheet discharge table 7 to the outside of the sheet discharge table 7. For this purpose, an opening (not shown) is formed in the partition plate 7b of the sheet discharge table 7 to allow the swing arm 26, the roller drive motor 30, and the roller 27 to pass therethrough.

Next, FIG. 4 shows an electrical block diagram of the paper discharge sorting apparatus A. A CPU 31 and a ROM 3 storing fixed data such as a program executed by the CPU 31;
2. A RAM 33 for storing variable data such as work data in an updatable manner, an interface 34 for inputting and outputting signals to and from the stencil printing apparatus, and the like are connected by a system bus. An I / O port 35 connected to the CPU 31 receives an HP (home position) sensor 36 for detecting a state in which the swing arm 26 has returned to an initial position outside the paper output tray 7 and a printing unit P (see FIG. 1). Paper S to be discharged
, A sheet sensor 38 for detecting a state in which the roller 27 of the pickup 25 contacts the sheet S on the sheet discharge table 7, a driver 39 for driving an arm drive motor 29, and a roller drive motor 30 Driver 40
Etc. are connected.

Here, the stencil printing apparatus can set a sorting printing mode. When sorting printing mode is set, to sort printed materials by sorting group,
The number of sheets to be printed at one time can be set. The set number of sheets is stored in a number counter (not shown). Then, for example, by decrementing the count value of this sheet counter each time one sheet is printed, the end of printing of the set number of sheets can be recognized when the count value becomes zero. .

Although the stencil printing apparatuses are not shown,
An image amount detecting unit for detecting an image amount to be printed on the sheet S, a sheet setting unit for specifying a type of the sheet S to be printed, a temperature detecting unit for detecting an ambient temperature, and a printing speed setting unit for setting a printing speed. I have. The image amount is configured to be detected by, for example, data stored in a page memory, and the printing speed is configured to be set by key input from an operation panel.

The settings on the stencil printing machine side, that is,
The state in which the sort print mode is set, the number of prints for each sort group, the image amount of the image to be printed on the paper S, the type of the paper S to be used, the detected temperature, and the waiting time according to the set print speed, etc. The value is output from an interface (not shown) as an output means of the stencil printing apparatus to the paper discharge sorting apparatus A.
Is stored in the RAM 33 via the interface 34. The waiting time is the time from when the paper Sa to be sorted is discharged to the paper discharge tray 7 to when the arm drive motor 29 is driven.

Hereinafter, the printing operation will be described. The stencil printing apparatus performs printing in the order of the process shown in FIG. As described above, the printing process includes a document image reading process (S5-1), a plate discharging process of removing the used master 1 from the plate cylinder 2 (S5-2), and a plate making process of the master 1 (S5-2). S5-3) and print processing (S5-4). In this printing, when performing the sort printing, the stencil printing apparatus sets the sort mode, the number of prints for each sort group, the number of sets of sort groups, and the like as described above.

In the paper sorting device A, as shown in FIG.
First, it is determined whether the sorting printing mode is set in the stencil printing apparatus (S6-1). When it is determined that the sorting printing mode is set (Y in S6-1), the set value of the waiting time is recognized (S6-2).

Next, it is determined whether or not the paper Sa to be sorted has been discharged (S6-3). As described above, since the number of prints is counted on the stencil printing machine side as described above, the paper S to be discharged next is sorted based on the count value received via the interface 34.
Is determined by the CPU 31 to determine whether the sheet Sa is detected by the sheet discharge sensor 37.
1 is performed by a process such as recognition.

Of the sheets S discharged to the sheet discharge tray 7, the sheets to be sorted will be described with reference numerals of Sa in order to distinguish them from other sheets S. If it is recognized that the operation has been performed (Y in S6-3), the arm drive motor 29 is driven in the counterclockwise direction, and the swing arm 26 is rotated in the counterclockwise direction from the initial position, so that (S6-4), and the rollers 2 are applied to the paper Sa on the paper output tray 7.
When the state where the sheet 7 is in contact is recognized by the ON output of the sheet sensor 38 (Y in S6-5), the arm drive motor 29
Is stopped (S6-6). The position of the swing arm 26 at this time is shown by a virtual line in FIG.

When it is recognized that the set waiting time has elapsed (S6-7), the sorting is executed.
This sorting is performed by driving the roller drive motor 30 and rotating the roller 27 counterclockwise (S6-
8). As a result, the paper Sa on the discharge tray 7 is shifted toward the partition plate 7b of the discharge tray 7. Since the shift amount of the sheet Sa at this time is set in advance by the number of pulses for driving the roller drive motor 30, when the roller drive motor 30 is driven by the set number of pulses, the sheet Sa is shifted to the sorting position. Then, the roller drive motor 30 is stopped, and the roller 27 is stopped (S6-10).

Subsequently, the arm drive motor 29 is driven clockwise to rotate the swing arm 26 clockwise. That is, when the swing arm 26 is retracted to the outside of the paper discharge tray 7 (S6-11), and it is recognized that the swing arm 26 has returned to the initial position based on the detection signal of the HP sensor 36 (S6-12). , Stop the arm drive motor 29,
The swing arm 26 is stopped (S6-13).

The sorting operation of the sheet discharge sorting apparatus A is performed by recognizing the setting state of the perforated sheet printing apparatus by the CPU 31 and executing a program written in the ROM 32. Therefore, the sorting operation is performed as long as the sorting printing is continued in the stencil printing apparatus,
If sorting printing is not performed, no sorting operation is performed.

At the time of printing, the drying state of the printed image changes depending on the image amount, the type of the sheet S, the ambient temperature, the printing speed, and the like. In accordance with these conditions, the sheet Sa to be sorted is discharged. Since the waiting time from when the sheet is sorted to when the sorting operation is performed can be changed, the paper S to be sorted can be changed.
After the paper S of the next layer discharged before a is dried to some extent, the paper Sa to be sorted can be shifted in the sorting direction. Thus, even if the next layer paper S is rubbed against the uppermost layer paper Sa to be sorted, the ink of the next layer paper S does not adhere to the back surface of the sheet Sa to be sorted.

Here, S6-2 to S6-8 are time changing means for changing the waiting time from the time when the paper Sa to be sorted is discharged to the time when the pickup driving section (the roller driving motor 30) is driven. Equivalent to.

Note that, as shown in FIG.
Inclined surface 26 for guiding sheet S to end plate 7a side
By forming the sheet a, the sheet S of the next sorting group is ejected while the swing arm 26 is positioned inside the sheet ejection tray 7 after sorting by the rollers 27, and at this time, the sheet ejection is performed. A program relating to the sorting operation may be set so that the cut sheet S is guided toward the end plate 7a by the inclined surface 26a.

In this way, when the image amount is small,
In the case of a high-temperature environment, when it is determined that the ink of the paper S that has already been printed is dry because the printing speed is low,
In the case where the ink transfer amount is small due to the high printing speed, or in the case where the paper S having high ink absorbency such as loose paper is used, from the time when the paper to be sorted is discharged to the time when the sorting operation is performed. Can be shortened, so that the printing cycle can be shortened when sorting printing is performed continuously.

Further, in place of the roller 27, FIG.
As shown in (2), by using the roller 42 having a large number of protrusions 41 on the outer periphery, the contact area of the roller 42 with the sheet S discharged to the sheet discharge table 7 immediately after printing can be reduced. Thereby, the stain of the ink due to the rubbing of the print image by the roller 42 can be reduced, and furthermore, the dirt on the paper S due to the dirt can be alleviated because the dirt is not easily attached. Further, since the tip of the protrusion 41 is sharp, the paper S can be moved without slipping. As shown in FIG. 7B, such an effect is obtained by providing a large number of needle-like protrusions 43 on the outer periphery.
7C, or as shown in FIG. 7C, a roller 46 having a number of protrusions 45 having a suction cup shape made of a soft material such as rubber. The sucker-shaped projections 45 are not sharpened like the other projections 41 and 43, but have a concave central portion, so that the contact area with the paper S can be reduced. Since the center is concave and the peripheral edge is elastically bent, the sheet S has a good attraction to the sheet S, whereby the sheet S can be surely moved without slipping.

According to the present invention, the pickup driving unit (the roller driving motor 30) is driven from the time when the paper Sa to be sorted according to various situations in which the ink of the printed image is difficult to dry is discharged to the discharge tray 7. Since the waiting time before the change is changed, the mechanism of the paper sorting device is not limited to the above embodiment. Another example of a paper sorting device having a different mechanism will be described.

First, a second embodiment of the present invention will be described with reference to FIGS. In this embodiment and other embodiments that follow it, the same reference numerals are used for portions having the same structure as in the previous embodiment, and description thereof is omitted. The paper sorting device B according to the present embodiment includes a guide rod 47 vertically supported by a support member (not shown).
And a pickup 49 which is horizontally movably fitted in a tunnel-shaped opening of the lift table 48. The pickup 49 includes a pressing plate 51 rotatable around a support shaft 50 at an end thereof, and further includes a pressing portion 52 fixed to a lower surface on a free end side of the pressing plate 51. The pressing plate 51 is urged counterclockwise (downward) by a spring (not shown) mounted on the support shaft 50. Therefore, the reaction force of the spring increases as the angle at which the pressing plate 51 rotates clockwise increases, and the pressing force on the sheet S in the sheet discharge tray 7 increases. Further, a detection piece 53 is formed integrally with the pressing plate 51, and the rotation angle of the pressing plate 51 is detected in a plurality of steps (two steps in the embodiment) by detecting the detection piece 53. And second pressure sensors 54 and 55 are provided at the tip of the pickup 49.

A feed screw 56 parallel to the guide rod 47 is screwed into the lift table 48, and the feed screw 56 is rotated by a lift motor 57 that can rotate forward and reverse, so that the lift table 4 is rotated.
8 rises or falls. The elevating table 48 supports a forward / backward rotatable forward / backward motor (pickup drive unit) 58, and a pinion 59 driven by the forward / backward motor 58 is engaged with a rack 60 formed on the pickup 49. In FIG. 9, the partition plate 7b of the paper discharge tray 7 includes
An opening (not shown) for allowing the pickup 49 to move forward and backward is formed.

The sorting process in the paper sorting device B will be described with reference to the flowchart shown in FIG. Usually, the elevating table 48 is located at an initial position (elevating position), and the pickup 49 is located at an initial position where the pressing plate 51 waits outside the sheet discharging table 7. Then, similarly to the case of the previous embodiment, the state in which the sorting print mode is set is recognized (Y in S10-1), and the waiting time is recognized (S10).
(Y of -2), when the state that the paper Sa to be sorted is discharged to the paper discharge tray 7 is recognized (Y of S10-3), the forward / backward motor 58 is rotated forward to move the pickup 49 inside the paper discharge tray 7. (S10-4). This forward position is shown in FIG.
Is the position indicated by the solid line. It should be noted that when the state where the pickup 49 has reached the foremost position (the position where the pressing plate 51 advances into the paper discharge tray 7) as shown in FIG. 9 is recognized based on a detection signal of a stroke sensor (not shown) (S10-5). Y),
The moving motor 58 is stopped, and the pickup 49 is stopped (S10-6).

Subsequently, the lift motor 57 is rotated forward to lower the lift table 48 (S10-7).
When recognizing that the third or second pressure sensor 54 is turned on (Y in S10-8), the elevating motor 57 is stopped and the elevating table 48 is stopped (S10-9). In this case, comparing the case where the lift 48 is lowered until the first pressure sensor 53 is turned on and the case where the lift 48 is lowered until the second pressure sensor 54 is turned on, the latter is better. The pressing force (paper holding force) for pressing the paper Sa with the pressing plate 51 is large. The latter corresponds to paper Sa having a large size, a large thickness, and heavy weight. Any of the pressure sensors 53,
Whether the elevator 48 is stopped based on the detection signal of 54 may be set in advance.

Subsequently, when it is recognized that the waiting time has elapsed (Y in S10-10), the forward / backward motor 58 is reversed, and the pickup 49 is moved backward (S10-11).
When it is recognized from the detection signal of the stroke sensor (not shown) that the pickup 49 has retreated to the paper shift position (Y in S10-12), the forward / backward motor 58 is stopped and the pickup 49 is stopped (S10- 1
3). At this time, the retreat length of the pickup 49 is
The length is such that the paper Sa to be sorted is shifted to the vicinity of the partition plate 7b.

Subsequently, the lift motor 57 is rotated in the reverse direction to raise the lift 48 (S10-14), and it is recognized from the detection signal of the upper limit sensor (not shown) that the lift 48 has reached the initial position. At this time (Y in S10-15), the lifting motor 57 is stopped, and the lifting table 48 is stopped (S10-
16) The forward / backward motor 58 is rotated in the reverse direction to
Is retracted to the outside of the paper discharge tray 7 (S10-17), and when the state where the pickup 49 has reached the initial position is recognized by the detection signal of the HP sensor (Y in S10-18), the forward / backward motor 58 is stopped. Then, the pickup 49 is stopped at the initial position (S10-19).

Here, S10-2 to S10-11
Corresponds to time changing means for changing the waiting time from the time when the paper Sa to be sorted is discharged to the time when the pickup driving unit (the forward / backward motor 58) is driven.

Next, a third embodiment of the paper discharge sorting apparatus according to the present invention will be described with reference to FIG. The paper discharge sorting device C in the present embodiment uses a pickup 61 instead of the pickup 49 shown in FIGS. The pickup 61 is held by an elevating table 48 which is driven by an elevating motor 57 to move up and down, and is provided by a reciprocating motor 58 so as to reciprocate between the outside and the inside of the sheet discharge table 7. The pickup 61 has a pressing portion 62 at the lower end of the tip, and an inclined surface 6 on the upper side of the pressing portion 62 for guiding the sheet S to be discharged toward the end plate 7a.
3 are formed. The pressing portion 62 is formed in a sharp shape in order to increase the coefficient of friction with the paper Sa to be sorted. Further, the pickup 61 has
A pressure reference sensor (not shown) that is turned on when the paper Sa in the inside is pressed with a certain pressing force is provided.
The pressure reference sensor detects the pressure on the paper Sa and outputs a detection signal.

In such a paper discharge sorting apparatus C, when the paper Sa to be sorted is discharged to the paper discharge tray 7, the pickup 61 is advanced to the inside of the paper discharge tray 7, and the paper Sa to be sorted is removed. The procedure for lowering the elevating table 48 for pressing and performing the sorting by the retreating operation of the pickup 61 is the same as in the previous embodiment. In other words, the lowering of the elevating table 48 causes the pressing portion 62 to press the sheet Sa in the sheet discharging table 7 and the pressure reference sensor to be turned on. When the state is recognized, the operation of the elevating motor 57 is controlled. 48
At a predetermined height. Thus, similarly to the case of the previous embodiment, the pressing of the pickup 61 on the sheet Sa is determined.

Subsequently, when it is recognized that the waiting time from the time when the paper Sa to be sorted is discharged to the time when the pickup driving unit (the forward / backward motor 58) is driven has elapsed,
When the forward / backward motor 58 is reversed, the pickup 61 is moved backward, and when it is recognized from the detection signal of the stroke sensor (not shown) that the pickup 61 has moved back to the paper shift position, the forward / backward motor 58 is stopped, and the pickup 61 is stopped. To stop. Thereby, the paper S to be sorted is
Although a is shifted to the partition plate 7b side by the sharp pressing portion 62 of the pickup 61, the sorting is performed after the elapse of the waiting time, so that the ink of the next layer paper S adheres to the sorted paper Sa. There is no.

As described above, this embodiment is different from the previous embodiment in the structure and the sorting operation of the sheet discharging / sorting apparatus C, but from the time when the paper Sa to be discharged is discharged to the time when the sorting operation is performed. The control operation for changing the waiting time is the same as in the first and second embodiments, and a description thereof will be omitted. This is the same in the following embodiments.

Next, a fourth embodiment of the paper sorting apparatus according to the present invention will be described with reference to FIG. The paper discharge sorting apparatus D according to the present embodiment uses a pickup 64 instead of the pickup 49 shown in FIGS. The pickup 64 is held by an elevating table 48 which is driven by an elevating motor 57 to move up and down. The pickup 64 is driven by an advancing and retreating motor 58 to reciprocate between the outside and the inside of the sheet discharge table 7. The pickup 64 includes a gripper 65 that grips the paper Sa to be sorted at the leading end in a vertical direction,
An opening / closing drive unit (not shown) for opening and closing the grip 65 is provided.

In this paper discharge sorting apparatus D, when the number of prints in one sorting group is n, the pickup 6 is driven when the (n-1) th sheet S is discharged to the paper discharge tray 7.
4 is advanced to the inside of the paper discharge tray 7 and
Is lowered to the (n−1) th sheet S, and when the nth sheet, that is, the sheet Sa to be sorted is discharged to the sheet discharge tray 7, the gripping portion 65 is driven to drive the sheet to be sorted. Sa is gripped by the gripper.

Subsequently, when it is recognized that the waiting time from the time when the paper Sa to be sorted is discharged to the time when the pickup drive unit (the forward / backward motor 58) is driven has elapsed,
The reciprocating motor 58 is reversed, the pickup 64 is retracted, and when it is recognized from the detection signal of the stroke sensor (not shown) that the pickup 64 has retreated to the sheet shifting position, the reciprocating motor 58 is stopped and the pickup 64 is stopped. To stop. Thereby, the paper S to be sorted is
Although a is shifted to the partition plate 7b side while being held by the holding portion 65 of the pickup 64, the sorting is performed after the elapse of the waiting time, so that the ink of the next layer paper S is applied to the sorted paper Sa. Will not adhere.

[0065]

According to the first aspect of the present invention, there is provided a paper discharge tray for sequentially loading printed sheets which are discharged from an image forming apparatus and fall, and sheets to be sorted from the image forming apparatus when a sort printing mode is set. A pickup that is driven by a pickup driving unit when paper is discharged and shifts the paper to be discharged in the sorting direction, and drives the pickup driving unit from the time when the paper to be sorted is discharged from the image forming apparatus. And a time changing means for changing the waiting time until the paper to be sorted can be shifted in the sorting direction at a time corresponding to the dry state of the printed image of the paper overlapping below the paper to be sorted. Therefore,
It is possible to avoid a state in which the ink of the paper discharged to the discharge tray before the paper to be sorted adheres to the back surface of the discharged paper. In the case of printing conditions that can speed up the drying of the ink, the time from when the paper to be sorted is discharged to when the sorting operation is performed can be shortened.
The printing cycle can be shortened.

According to a second aspect of the present invention, there is provided an image forming apparatus, comprising: a printing unit; an image amount detecting unit for detecting an amount of an image to be printed on a sheet; Output means for outputting to the time changing means of the paper discharge sorting apparatus a command to change the waiting time from when the paper to be sorted is discharged to the paper discharge tray to when the pickup drive unit is driven. Accordingly, the waiting time from when the paper to be sorted is discharged to the paper discharge tray to when the pickup driving unit is driven is determined according to the image amount. Thereby, the paper to be sorted can be shifted in the sorting direction at a time corresponding to the dry state of the print image of the paper overlapping on the lower side of the paper to be sorted.

According to a third aspect of the present invention, there is provided an image forming apparatus comprising: a printing unit; a paper setting unit for designating a type of paper; a paper discharge sorting device according to the first aspect; Output means for outputting to the time changing means of the paper discharge sorting apparatus a command to change the waiting time from when the paper to be ejected to the paper discharge tray to when the pickup drive section is driven. Therefore, the waiting time from when the paper to be sorted is discharged to the paper discharge tray to when the pickup driving unit is driven is determined according to the type of the specified paper. Thereby, the paper to be sorted can be shifted in the sorting direction at a time corresponding to the dry state of the print image of the paper overlapping on the lower side of the paper to be sorted.

According to a fourth aspect of the present invention, there is provided an image forming apparatus comprising: a printing section; a temperature detecting means for detecting a temperature; a sheet discharge sorting apparatus according to the first aspect; Output means for outputting a command to change the waiting time from when the paper is discharged to the paper tray to when the pickup drive unit is driven to the time changing means of the paper discharge sorting device. The waiting time from when the paper is discharged to the paper discharge tray to when the pickup driving unit is driven is determined according to the detected temperature. Thereby, the paper to be sorted can be shifted in the sorting direction at a time corresponding to the dry state of the print image of the paper overlapping on the lower side of the paper to be sorted.

According to a fifth aspect of the present invention, there is provided an image forming apparatus comprising: a printing unit; a printing speed setting unit for setting a printing speed;
And a command to change a waiting time from a timing at which sheets to be sorted according to a set print speed are discharged to the discharge to a time at which the pickup driving unit is driven is described. Output means for outputting to the time changing means of the paper discharge sorting device, so that the printing speed in which the waiting time from when the paper to be sorted is discharged to the paper discharge table to when the pickup driving unit is driven is set. It is determined according to. Thereby, the paper to be sorted can be shifted in the sorting direction at a time corresponding to the dry state of the print image of the paper overlapping on the lower side of the paper to be sorted.

[Brief description of the drawings]

FIG. 1 is a vertical sectional front view showing a paper discharge sorting apparatus according to a first embodiment of the present invention together with a stencil printing apparatus.

FIG. 2 is a perspective view showing a swing arm.

FIG. 3 is a vertical sectional front view showing a paper discharge sorting device.

FIG. 4 is an electrical block diagram.

FIG. 5 is a flowchart illustrating a printing process of the stencil printing apparatus.

FIG. 6 is a flowchart illustrating a sorting process.

FIG. 7 is a front view showing a modified example of the roller of the pickup.

FIG. 8 is a perspective view showing a paper discharge sorting device according to a second embodiment of the present invention.

FIG. 9 is a vertical sectional front view of the paper discharge sorting device.

FIG. 10 is a flowchart illustrating a sorting process.

FIG. 11 is a vertical sectional front view showing a paper discharge sorting apparatus according to a third embodiment of the present invention.

FIG. 12 is a longitudinal sectional front view showing a paper discharge sorting apparatus according to a fourth embodiment of the present invention.

[Explanation of symbols]

 7 Discharge table 25, 49, 61, 64 Pickup 30, 58 Pickup driving unit P Printing unit S Paper Sa Paper to be sorted S6-1 to S6-8 Time changing means S10-2 to S10-11 Time changing means

Claims (5)

[Claims] A discharge tray for sequentially stacking printed sheets discharged from the image forming apparatus and dropping, and a pickup when a sheet to be sorted is discharged from the image forming apparatus when a sorting print mode is set A pickup driven by a drive unit to shift sheets to be discharged in a sorting direction, and a time for changing a waiting time from a time when the sheets to be sorted from the image forming apparatus are discharged to a time when the pickup driving unit is driven. A paper sorting device comprising a change unit. 2. A printing unit, an image amount detecting unit for detecting an image amount to be printed on a sheet, a sheet discharge sorting device according to claim 1, and a sheet to be sorted according to the detected image amount. An image forming apparatus comprising: an output unit that outputs a command to change a waiting time from when the sheet is discharged to the table to when the pickup driving unit is driven to a time changing unit of the sheet discharge sorting device. 3. A printing unit, paper setting means for specifying a paper type, a paper discharge sorting device according to claim 1, and paper to be sorted according to the specified paper type are stored in said paper output tray. An image forming apparatus comprising: an output unit that outputs a command to change a waiting time from when the sheet is ejected to when the pickup driving unit is driven to a time changing unit of the sheet sorting device. 4. A printing section, a temperature detecting means for detecting a temperature, a sheet discharge sorting apparatus according to claim 1, and a sheet to be sorted according to the detected temperature is discharged to said sheet discharge table. An output unit that outputs a command to change a waiting time from a time until the pickup driving unit is driven to a time changing unit of the sheet discharge sorting device. 5. A printing section, a printing speed setting means for setting a printing speed, a paper discharge sorting device according to claim 1, and a paper to be sorted according to the set printing speed is discharged to said paper discharge. And an output unit that outputs a command to change a waiting time from when the operation is performed to when the pickup driving unit is driven to the time changing unit of the sheet discharge sorting device.