JPH07144402A - Printer - Google Patents

Abstract

PURPOSE:To prevent offset from being caused in a printing paper sheet which is fed from a paper feeder without increasing the cost by mounting a control means or the like which operates traveling means every other sheet. CONSTITUTION:The second printing paper sheet P is conveyed to a pair of register rollers 10 in the same way as the first paper sheet. After taking timing for a printing drum 16, the pair of register rollers 10 feed the printing paper sheet P between the printing drum 16 and a press roller 17. At that time, a signal is outputted from a paper sensor 13 and is compared with the printing data stored in a ROM by a CPU. Printing for the third paper sheet is carried out in the same way as the first one, and printing for the fourth paper sheet is carried out in the same way as the second one to the preset number of printing paper sheets. The printing data that the press rollers 17 are moved in printing for odd number of paper sheets and the press roller 17 is not moved for even number of paper sheets are stored in the ROM, by which it is possible to stack printed paper sheets and unprinted paper sheets by turns.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for show-through prevention printing and simple sorting printing in a printing press.

[0002]

2. Description of the Related Art In a general printing apparatus, the ink transferred to the printing paper during printing penetrates into the printing paper and does not stain even if rubbed with a finger or the like, in a so-called set state. By the time this set is complete,
It took some time. Then, if the next printing paper is stacked before the setting is completed, the so-called show-through problem occurs, in which the ink of the image portion of the previous printing paper is transferred to the back surface of the next printing paper. Was. This show-through is not a serious problem in normal printing in which printing is performed on only one side of the printing paper, but it is a serious problem in double-sided printing and postcard printing.

To prevent such show-through, therefore, the printing speed is lowered, the drum is idled several times to increase the paper feed interval, or a collating device having a plurality of sort bins is connected. A measure is taken to discharge the printed sheets one by one to each bin to gain time until the next printed sheet overlaps.

Further, when the sheets are sorted, a collating device and a sorting device (see Japanese Patent Laid-Open No. 4-246057) are connected to the printing device to perform sorting.

[0005]

However, in the above-mentioned measures for preventing show-through, there is a problem that the efficiency of the printing operation is lowered if the printing speed is lowered or the drum is idled to widen the paper feeding interval. Further, in the measure for connecting the collating device to increase the time for discharging the paper, there is a problem that the cost is increased by connecting the collating device.

Further, even when the sheets are sorted, there is a problem that the cost is increased by connecting the collating device and the sorting device.

The present invention provides a printing apparatus which solves the above-mentioned problems, prevents the show-through of the printing paper without lowering the efficiency of the printing work and increasing the cost, and is capable of separating the paper. With the goal.

[0008]

The invention according to claim 1 is
A rotatable drum, a press roller movably provided between a first position, which is an initial position separated from the outer peripheral surface of the drum, and a second position in contact with the outer peripheral surface,
A sheet feeding device for feeding a printing sheet and a moving unit for reciprocating the press roller between the first position and the second position, and an interleaf sheet between printed sheets. In a printing apparatus having an interleaving paper mode for inserting a sheet, when the interleaving mode is selected and printing is performed, the moving unit is moved every other sheet with respect to the printing paper fed from the paper feeding apparatus. It is characterized by comprising a control means for activating.

According to a second aspect of the present invention, in the printing apparatus according to the first aspect, the sheet feeding device further has a plurality of sheet feeding trays, the interleaf sheet mode is selected, and the sheet feeding operation is performed. When printing is performed by designating the printing paper feed tray and the interleaving paper feed tray from the tray, the printing paper tray and the interleaving paper feed tray are alternately switched to set the printing paper to 1 The paper is fed sheet by sheet, and the moving means is operated for the printing paper fed from the printing paper feed tray, and the printing paper is fed as the interleaving paper fed from the interleaf paper feed tray. For printing paper, a control means for stopping the operation of the moving means is provided.

According to a third aspect of the present invention, there is provided a rotatable drum and a first position which is an initial position separated from an outer peripheral surface of the drum.
And a second position in contact with the outer peripheral surface, a press roller movably provided, a paper feeding device for feeding a printing paper, the press roller, the first position and the second position. A group having a moving means for reciprocating between the second position and a predetermined number of sheets printed on one original plate, and inserting interleaving paper between groups of the predetermined number of printed sheets. In a printing apparatus provided with a grouping mode, when the grouping mode is selected and the number of groups and the number of prints for each group are respectively specified for printing, the movement is performed until the printing of the first group is completed. When the sheet feeding device feeds one sheet of the printing sheet as the interleaf sheet after the completion of printing of the first group, the operation of the moving section is stopped, and then the next During printing of the loop, characterized by comprising a control means for actuating the moving means again.

According to a fourth aspect of the present invention, in the printing apparatus according to the third aspect, the sheet feeding device further has a plurality of sheet feeding trays, the grouping mode is selected, and the sheet feeding is performed. Specify the paper tray for printing and the paper tray for interleaving from the tray, and specify the number of groups, 1
When printing is performed by designating the number of prints in each group, for the printing of the first group, the paper is fed from the printing paper tray and the moving means is operated,
After the printing of the first group is completed, one sheet of the printing paper as the interleaving paper is fed from the interleaving paper feeding tray and the operation of the moving means is stopped, and thereafter, when printing the next group, It is characterized by further comprising control means for activating the moving means again.

According to a fifth aspect of the present invention, in the printing apparatus according to the third aspect, the paper feeding device further has a plurality of paper feeding trays, and each of the paper feeding trays is moved in a direction orthogonal to the paper feeding direction. And a paper feed tray moving unit for selecting the grouping mode, designating a paper feed tray and an interleaf paper feed tray from each of the paper feed trays, and setting the number of groups and 1 When printing is performed by designating the number of prints in each group, when printing the first group, after feeding the paper from the printing paper feed tray and operating the moving means, after printing the first group, Is moved by the paper feed tray moving means, and feeds one sheet of the printing paper as the interleaving paper from the paper feed tray for interleaving paper whose paper feed position is different from that of the paper feeding tray for printing. Stops the operation of said moving means together with, then, at the time of the next group printing, characterized by comprising a control means for actuating the moving means again.

According to a sixth aspect of the invention, there is provided a rotatable drum and a first position which is an initial position separated from an outer peripheral surface of the drum.
And a second position in contact with the outer peripheral surface, a press roller movably provided between the position and a plurality of paper feed trays, and a paper feeding device for feeding paper, and the press roller. , A moving unit for reciprocating between the first position and the second position, and a sorting mode for sequentially feeding a predetermined number of sheets from each of the paper feed trays. In the printing apparatus, the sorting mode is selected, the feeding order from each of the paper feed trays, the number of fed sheets, and the number of bins are respectively specified, and the paper fed from each of the paper feed trays is sorted. At this time, the paper is fed from each of the paper feed trays according to the designated paper feed order, the number of fed paper sheets, and the number of classified papers, and the paper fed from each of the paper feed trays is Control means for stopping the operation of the moving means Characterized by comprising.

[0014]

According to the first aspect of the invention, when the interleaf sheet mode is selected and printing is performed, the control means causes the moving means to move every other sheet with respect to the printing paper fed from the paper feeding device. Since every other printing paper is brought into contact with the outer peripheral surface of the drum by the operation, the non-printed paper is sandwiched between the printed papers.

According to the second aspect of the present invention, when the interleaf sheet mode is selected and the printing paper feed tray and the interleaf paper feed tray are respectively designated from the plurality of paper feed trays, printing is performed. The control means alternately switches the printing paper feed tray and the interleaving paper feed tray to feed the printing papers one by one, and to the printing papers fed from the printing paper feed tray. Operates the moving means to stop the operation of the moving means with respect to the printing paper as the interleaf paper fed from the interleaf paper feed tray. Therefore, the printing fed from the paper feed tray for printing is stopped. The unprinted sheets fed from the slip sheet feed tray are sandwiched between the finished sheets as slip sheets.

According to the third aspect of the present invention, when the grouping mode is selected and the number of groups and the number of prints for one group are designated for printing, the control means sets the printing of the first group. Until the end, the moving means is operated, and after the printing of the first group is completed, when the paper feeding device feeds one printing sheet as interleaving paper, the operation of the moving means is stopped, and then the next group is printed. At the time of printing, since the moving means is operated again, the unprinted paper is sandwiched between the groups.

According to the fourth aspect of the present invention, the grouping mode is selected, and the printing paper feed tray and the interleaving paper feed tray are designated from a plurality of paper feed trays.
Moreover, when printing is performed by designating the number of groups and the number of prints of each group, the control means performs the feeding from the printing paper feed tray and activates the moving means for the printing of the first group. After printing for the first group, print one sheet of interleaving paper from the interleaving paper tray.
After feeding the sheets and stopping the operation of the moving means,
When the next group is printed, the moving means is activated again, so there is no printing between the groups of printed paper fed from the printing paper feed tray and paper fed from the interleaf paper feed tray. The paper is sandwiched as interleaving paper.

According to the fifth aspect of the present invention, the grouping mode is selected, and the printing paper feed tray and the interleaving paper feed tray are designated from a plurality of paper feed trays.
Moreover, when printing is performed by designating the number of groups and the number of prints of each group, the control means performs the feeding from the printing paper feed tray and activates the moving means for the printing of the first group. After the printing of the first group is completed, it is moved by the paper feed tray moving means, and one sheet of print paper is fed as the interleaf paper from the paper feed tray for printing and the paper feed tray for which the paper feed position is different. And the operation of the moving means is stopped, and then when printing the next group,
Since the moving means is activated again, the unprinted paper fed from the interleaf paper feed tray is discharged between each group of printed paper fed from the print paper feed tray.
The positions are shifted and sandwiched as interleaving paper.

According to the sixth aspect of the present invention, the sorting mode is selected, the sheet feeding order of the plurality of sheet feeding trays, the number of sheets to be fed, and the number of sorting are specified respectively, and the sheets are fed from each sheet feeding tray. When sorting the paper, the control means causes the paper to be fed from each paper feed tray according to the designated paper feed order, the number of fed paper sheets, and the number of bins, and the paper fed from each paper feed tray. In this case, since the operation of the moving means is stopped, the sheets are sequentially conveyed without being printed.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1 showing an embodiment of the present invention, a printing apparatus 1 comprises a paper feeding device 2, a printing section 3 and a paper ejection section 4. In this embodiment, in addition to the sheet feeding device 2 provided integrally with the casing 5 of the printing apparatus 1, a sheet feeding device 6 having a structure different from that of the casing 5 as shown in FIG. is doing.

The paper feeding device 2 is mainly composed of a paper feeding tray 7, a paper feeding roller 8, a separation pad 9, a pair of registration rollers 10, and the like. The paper feed tray 7 is detachably attached to the housing 5, and the print paper P is stacked on the upper portion of the paper feed tray 7a provided inside. The paper feed tray 7 is configured in the same manner as the paper feed tray 37 described later, and the stacked printing paper P is pressed against the paper feed roller 8 by the vertical movement mechanism 42 described later. The paper feed tray 7a is movably supported by a paper feed tray moving means 41, which will be described later. The paper feed roller 8 is rotatably driven by a driving unit (not shown), and scoops up and feeds the print paper P that contacts the outer peripheral surface thereof.
The drive means for driving the paper feed roller 8 is controlled in its operation by the control means described later. When the paper feed roller 8 feeds the print paper P, the print paper P is prevented from being double-fed by the separation pad 9. A sheet conveying path 11 is formed on the left side of the sheet feeding roller 8 and the separation pad 9, and a registration roller pair 10 which is rotationally driven by a driving unit (not shown) is arranged on the left side of the sheet conveying path 11. On the left side of the registration roller pair 10 and in the vicinity of the printing unit 3, a paper transport path 12 that guides the printing paper P to the printing unit 3 is formed. Below the paper transport path 12, a paper sensor 13 that detects whether or not the print paper P is present inside the paper transport path 12 is provided. The signal output from the paper sensor 13 is input to the control means described later. Further, the paper transport path 11 is
It branches downward from the end portion on the registration roller pair 10 side, and forms a sheet conveyance path 14. The sheet transport path 14 is provided so as to open at the bottom of the housing 5, and a rotatable transport roller pair 15 is disposed in the middle thereof.

A printing unit 3 is arranged on the left side of the paper feeding device 2. The printing unit 3 mainly includes a printing drum 16, a press roller 17, and the like. The printing drum 16 is
It is rotatably supported by a side plate (not shown), and is rotationally driven by a driving means (not shown). As shown in FIG. 2, a press roller 17 is arranged below the printing drum 16. The press roller 17 is formed so that its width is substantially the same as the width of the printing drum 16.
A shaft 17a is inserted and fixed in the central portion. Both ends of the shaft 17a are rotatably supported by the guide members 18, 18. A central shaft 19 is inserted and fixed to the end of the guide member 18, 18 opposite to the end supporting the shaft 17a. The center shaft 19 is rotatably supported by a side plate (not shown) of the housing 5, and at the end on the back side as viewed from FIG.
The actuating plate 20 has one end fixed thereto. Operating plate 20
Is a vertically long thin plate material, and a shaft 21a that rotatably supports the cam follower 21 is fixed to an end portion opposite to the end portion fixed to the central shaft 19. The actuating plate 20 is formed so that both side portions thereof project, and one end of a tension coil spring 22 is engaged with the projecting portion 20a on the printing drum 16 side. Tension coil spring 22
The other end of is fixed to a side plate (not shown) of the housing 5,
A biasing force in a counterclockwise direction in FIG. 2 is applied to the operating plate 20 about the central axis 19. Further, the projecting portion 20b of the operation plate 20 on the side of the sheet feeding device 2 can be engaged with and disengaged from a locking member 29 described later.

A printing pressure gear 23 is disposed further on the back side of the apparatus than the operating plate 20. The printing pressure gear 23 is rotatably supported by a side plate (not shown), and the pinion 2 fixed to the output shaft end of the motor 24 attached to the housing 5.
5, the rotational force is transmitted, and the rotational force is synchronized with the printing drum 16. On the front side of the printing pressure gear 23, the printing pressure cam 26 is arranged coaxially with the printing pressure gear 23. The printing pressure cam 26 is a plate member having a substantially 8-shape, and is rotationally driven by transmitting the rotational force of the motor 24. Printing cam 2
On the track formed on the outer peripheral surface of 6, the tension coil spring 2
The outer peripheral surface of the cam follower 21 urged by 2 contacts. The operating plate 20, the cam follower 21, the tension coil spring 22, the printing pressure gear 23, the motor 24, and the pinion 2 described above.
5, the printing pressure cam 26 and the like constitute the moving means 27.

Locking means 28 is provided near the sheet feeding device 2 side of the moving means 27. The locking means 28 is mainly composed of a locking member 29, a solenoid 30, a tension coil spring 31 and the like. The locking member 29 is a plate member having a substantially L shape, and is rotatably supported by the support shaft 32 at its bent portion. The support shaft 32 is embedded in a side plate (not shown) of the housing 5. One end 29a of the locking member 29 is engaged with one end of the tension coil spring 31, and the other end of the tension coil spring 31 is attached to the side plate of the housing 5. As a result, a counterclockwise biasing force is applied to the locking member 29 about the support shaft 32 in FIG. Further, the tip of the plunger 30a of the solenoid 30 is rotatably attached to the one end 29a by a shaft 33. As a result, the locking member 29 has one end 29a.
Are supported by a solenoid 30, a tension coil spring 31, and a support shaft 32 so that they are substantially horizontal. Locking member 2
The other end 29b of 9 extends downward from the bent portion, and a cutout portion 29c is formed in the upper side edge portion thereof. The notch 29c has a protruding portion 20 of the operating plate 20.
b is detachable. The solenoid 30 has a housing 5
Is attached to the side plate of, and its operation is controlled by the control means described later.

At the lower left of the printing unit 3, a paper discharge unit 4 is arranged. The paper discharge unit 4 is mainly composed of a suction conveyance unit 34 and a paper discharge tray 35. Adsorption transport unit 3
Reference numeral 4 is attached to the housing 5, and peels the printed printing paper P from the outer peripheral surface of the printing drum 16 and
The printing paper P has a well-known structure in which the printing paper P is stiffened to improve the paper ejection alignment and then ejected to the outside of the machine. Output tray 3
Reference numeral 5 is removably attached to the housing 5 and sequentially stacks printed printing papers P ejected outside the machine by the suction conveyance unit 34.

An operation panel 66 is provided on the upper surface of the housing 5. The operation panel 66, as shown in FIG. 3, performs an interleaving key 67 for selecting an interleaving mode in which interleaving sheets are inserted between printed sheets, performs a predetermined number of printings for each original, and prints the predetermined number of sheets. Insert interleaving paper between groups of printed paper, grouping key 68 for selecting grouping mode, sequentially feed a predetermined number of sheets from a plurality of paper feed trays, for selecting sorting mode Sorting key 69, a tray selection key 70 for selecting a tray to be used from a plurality of paper feed trays, a leftward movement key 71a for moving the paper feed tray provided in the paper feed tray leftward, and a rightward movement key 71a. Right move key 7 for
1b, a paper feed tray moving key 71, a message display 72 for displaying print information, a ten key 73 for setting print conditions, and a start key 7 for starting printing.
4. A plate-making start key 82 for starting the plate-making operation is arranged. A control means 76 is provided below the operation panel 66 and inside the housing 5. The control means 76, as shown in FIG.
It is mainly composed of a RAM 78 and a ROM 79.

Below the housing 5, a sheet feeding device 6 having a different structure is connected. The paper feeding device 6 is mainly configured by a device main body 36, a plurality of paper feeding trays 37, 37, a paper feeding roller 8 similar to the paper feeding device 2, a separation pad 9, a pair of transport rollers 15, and the like. As shown in FIG. 5, the paper feed tray 37 includes a paper feed tray 38, a paper feed bottom plate 39, side guide plates 40, 40, and
It is mainly composed of a paper feed tray moving means 41, a vertical movement mechanism 42 and the like.

A guide shaft 43 is installed between the side plates 37a and 37b of the paper feed tray 37. The guide shaft 43 is inserted through the side plates 38a and 38b of the paper feed table 38, and the paper feed table 38 is supported by the guide shaft 43 so as to be slidable in the arrow X direction. A paper feed bottom plate 39, on which the print paper P is stacked, is arranged in the middle of the inside of the paper feed tray 38. The paper feed bottom plate 39 is engaged with the long holes formed in the side plates 38a, 38b by the protrusions 39a, 39b provided on both sides thereof, and is supported by the vertical movement mechanism 42 described below so as to be vertically movable. There is. On the upper surface of the paper feed bottom plate 39,
The side guide plate 4 for positioning the printing paper P in the width direction
0 and 40 are arranged. Side guide plates 40, 40
Is a well-known structure that is provided symmetrically with respect to the center of the printing paper P and is movable in the arrow X direction.

A paper feed tray moving means 41 is arranged in the lower stage inside the paper feed tray 38. Paper tray moving means 41
Is a motor 44, ball screw 45, slit disk 4
6 and the slit sensor 47 and the like.
The motor 44 is supported by a motor bracket 48, and the motor bracket 48 is used for the bottom plate 3 of the paper feed tray 38.
It is attached to 8c. Output shaft 44 of motor 44
a is joined to a shaft 50 on which a ball screw 45 is engraved via a joint portion 49, and the shaft 50 is the ball screw 4
5, both ends of which are rotatably supported by support members 51 mounted on the bottom plate 38c, and at their free ends,
The slit disk 46 is fixedly installed. A substantially L-shaped bracket 52 having one surface fixed on the bottom plate of the paper feed tray 37 is screwed into the ball screw 45. With this configuration, the ball screw 45 is rotated with respect to the immovable bracket 52 by the rotational force of the motor 44, and the sheet feeding table 38 is movable on the guide shaft 43 in the arrow X direction. The operation of the motor 44 is controlled by the control means 76.

On the slit disk 46, as shown in FIG. 6, a plurality of slits 53 are radially formed at equal intervals. A slit sensor 47 that counts the slits 53 is arranged at a position facing the slits 53, and the slit sensor 47 is fixed on the bottom plate 38c. The slit disc 46 and the slit sensor 47 constitute a movement amount detecting means 54. Also, the bottom plate 38
An initial position indicating plate 80 is fixed to the lower surface of c, and an initial position sensor 81 is attached on the bottom plate of the paper feed tray 37 at a position corresponding to this, and the center of the original image in the arrow X direction and the arrow of the printing paper P are attached. By providing the initial position indicating plate 80 at the position where the center in the X direction coincides, the deviation of the document image with respect to the printing paper P can be corrected by moving the paper feed tray 38 by the motor 44.

As shown in FIG. 7, the vertical movement mechanism 42 includes a gear motor 55, a worm 56, and a worm wheel shaft 5.
7, hub 58, fixed pulley 59, 59, 59, moving pulley 60,
60, a wire 61, a pulse generator 62, a remaining amount sensor 63 and the like. Gear head 5
The gear motor 55 having 5a is fixedly mounted on the bottom plate 38c, and its operation is controlled by the control means 76. One end of the worm 56 is joined to the gear head 55a, and the pulse generator 62 is fixedly provided at the other end. A remaining amount sensor 63 is arranged at a position facing the pulse generator 62, and the remaining amount sensor 63 is attached on the bottom plate 38c. The pulse generator 62 and the remaining amount sensor 63 form a sheet detecting unit 65. Worm wheel shaft 5 engraved with worm wheel 57a that meshes with worm 56
7 are brackets 64, 64 fixed on the bottom plate 38c.
Is rotatably supported by the side plate 38a and the side plate 38a and the side plate 38b (not shown). A hub 58 is mounted near the side plate 38a of the worm wheel shaft 57, and a hub (not shown) is mounted on the other side of the side plate 38b, like the hub 58.

On the side plate 38a, two vertically formed
Three long holes 38d, 38d are formed. Each long hole 38
At the upper part of d and 38d and the lower part between each long hole, a fixed pulley 5
9, 59, 59 are rotatably attached, and movable pulleys 60, 60 are loosely fitted in the respective long holes so as to be vertically movable. The above-mentioned projections 39a, 39 of the sheet feeding bottom plate 39
The a is supported by the movable pulleys 60, 60. A wire 61 is wound around each fixed pulley and each moving pulley, and one end of the wire 61 is fixed to the hub 58 and the other end is fixed to one moving pulley 60. This hub, fixed pulley,
The movable pulley and the wire are also symmetrically configured on the side plate 38b side. With this configuration, the gear motor 5
When the worm wheel shaft 57 rotates in the counterclockwise direction in FIG. 7 by the rotation of 5, the wire 61 is wound around the hub 58, and the movable pulleys 60, 60 rise to push up the protrusions 39a, 39a, thereby supplying the power. The paper bottom plate 39 rises.

The printing paper P fed from the paper feed trays 37, 37 has a paper feed path 7 formed inside the paper feed device 6.
The sheet is conveyed by the pair of conveying rollers 15 through the sheet 5, and is conveyed to the pair of register rollers 10 through the sheet conveying path 14 opened at the bottom of the housing 5.

Based on the above configuration, the operation will be described below. As a first embodiment, a case of printing in the slip sheet mode will be described. Prior to printing, the operator sets a document on an image reading device (not shown), presses a plate making start key 82 on the operation panel 66, winds the plate making master on the outer peripheral surface of the printing drum 16, and then inserts a slip sheet key. 67 is pressed (when the master having been prepressed is already wound around the outer peripheral surface of the printing drum 16, the press of the prepress start key 82 is omitted). The signal is judged by the CPU 77, the print data is read from the ROM 79, and the message display 72 is instructed to set the number of trays to be used, the designated tray number and the number of prints, respectively. On the other hand, the operator designates the number of trays with the ten keys 73. Here, a case where one tray is selected will be described. Next, the operator selects and designates the tray to be used with the tray selection key 70, sets the number of prints with the ten keys 73, and then presses the start key 74. The input information designated here is input to the RAM 78.

When the start key 74 is pressed, the selected paper feed tray (any tray, the paper feed tray 37
The upper and lower moving mechanism 4 provided on the assumption that the upper stage is selected)
The second gear motor 55 rotates, and the wire 61 moves to the hub 5
It winds up to 8, and the movable pulleys 60, 60 are raised. As the movable pulleys 60, 60 rise, the paper feed bottom plate 39 rises and the upper surface of the stacked printing paper P contacts the paper feed roller 8, and the pressure on the paper feed roller 8 is a predetermined pressure stored in the ROM 79. Then, the rotation of the gear motor 55 is stopped, and the raising of the sheet feeding bottom plate 39 is stopped. At this time, as the worm 56 rotates, the pulse generator 62 rotates and a pulse is generated, and the remaining amount sensor 63 counts the number of pulses. The amount of movement of the sheet feeding bottom plate 39 changes depending on the number of stacked printing sheets P, and the number of pulses generated accordingly changes, so that the number of printing sheets P is detected and this signal is sent to the RAM 78. . Then, from this signal, the remaining number of print sheets P becomes less or 0
If the CPU 77 determines that
A print paper supply lamp (not shown) provided on 6 is turned on.

When the rising of the paper feed bottom plate 39 is stopped, the printing paper P
When is pressed against the paper feed roller 8 with an appropriate pressure, a command is issued from the control means 76 to rotate the paper feed roller 8 and feed the printing paper P. At this time, the printing paper P is separated one by one by the separation pad 9 and fed to the paper conveyance path 14. Paper transport path 1
The printing paper P sent to the sheet 4 is conveyed by the conveying roller pair 15, and when the leading end reaches a position where it abuts on the registration roller pair 10, a signal is output from the control means 76 and the conveying roller pair 15 is stopped. .

In parallel with the sheet feeding operation of the sheet feeding device 6, the printing section 3 is performing the printing operation. Along with the rotation of the printing drum 16, the registration roller pair 10 that has stopped
Rotates to feed the print paper P from the paper transport path 12 between the print drum 16 and the press roller 17. At this time, the leading edge of the printing paper P crosses the paper sensor 13, and the paper sensor 13 outputs a signal.
It is input to 78. The signal input to the RAM 78 is C
The PU 77 collates the print data stored in the ROM 79, and a signal is sent from the CPU 77 based on the print data to energize the solenoid 30.

The solenoid 30 attracts the plunger 30a when energized. Then, the locking member 29 is rotated clockwise around the support shaft 32 against the biasing force of the tension coil spring 31, and the operating plate in which the notch 29c of the locking member 29 locks the protrusion 20b. 20 is unlocked and is rotated counterclockwise about the central shaft 19 by the urging force of the tension coil spring 22. When the operating plate 20 rotates, the outer peripheral surface of the cam follower 21 comes into contact with the outer peripheral surface of the printing pressure cam 26, and the operating plate 20 is swung along the printing pressure cam 26.
The press roller 17 is moved to a second position where the outer peripheral surface of the press roller 17 contacts the outer peripheral surface of the printing drum 16.

Printing drum 1 by press roller 17
The printing paper P, to which the print image has been transferred by being pressed against the outer peripheral surface of 6, is separated from the outer peripheral surface of the print drum 16 by a peeling claw (not shown) arranged in the vicinity of the outer peripheral surface of the print drum 16, and then sucked and conveyed. The paper is conveyed while being united by the unit 34, and is discharged onto a paper discharge tray 35 outside the machine.

From the time when the press roller 17 comes into contact with the outer peripheral surface of the printing drum 16, the printing drum 16 makes about three quarters of the circumference, and the time when the most protruding portion of the printing pressure cam 26 and the cam follower 21 come into contact, that is, the When the notch 29c of the stop member 29 and the projecting portion 20b of the actuating plate 20 can be locked, a signal is sent from the control means 76 to interrupt the energization of the solenoid 30. Then, the locking member 29 is rotated counterclockwise by the urging force of the tension coil spring 31, and locks the protruding portion 20b of the operating plate 20 in the notch 29c. With this, the press roller 17 is held at the first position in which the outer peripheral surface of the printing drum 16 is separated from the outer peripheral surface thereof.

After the printing of the first sheet is completed, the second sheet is printed. Similarly to the first sheet, the second sheet of printing paper P is also conveyed to the registration roller pair 10 and timed with the printing drum 16, and then the registration roller pair 10 presses the printing sheet P against the printing drum 16. It is fed between the roller 17. At this time, similarly to the first sheet, a signal is output from the paper sensor 13 and this signal is input to the RAM 78. The signal input to the RAM 78 is collated by the CPU 77 with the print data stored in the ROM 79. This print data is different from the print data for the first sheet, so that the solenoid 30 should not be energized. Has become. Therefore, the press roller 17 does not move while being held at the first position, and the printing paper P is not
After passing between 6 and the press roller 17 and being conveyed to the suction conveyance unit 34, it is ejected onto the paper ejection tray 35.

After that, the third sheet is printed in the same manner as the first sheet,
In addition, the printing of the fourth sheet is performed up to the set number of prints similarly to the second sheet. In this way, by storing the print data in the ROM 79 that the press roller 17 is moved during printing of the odd number of sheets and that the press roller 17 is not moved during printing of the even number of sheets, the printed paper and the unprinted paper are recorded. And are alternately stacked on the discharge tray 35. As a result, the excess ink on the printed paper is absorbed by the unprinted paper as the interleaving paper, and the problem of ink show-through is prevented.

As a second embodiment, a case will be described in which, prior to printing, each item is set in the same manner as in the first embodiment, and two trays are selected with the ten keys 73 when setting the number of trays to be used. . Operator selects tray selection key 7
When 0 is selected, the printing paper feed tray and the interleaving paper feed tray are selected and designated, and the start key 74 is pressed. Start key 7
When 4 is pressed, the vertical movement provided in each selected tray (assuming that the upper tray of the paper feed tray 37 is selected as the paper feed tray for printing and the paper feed tray 7 is selected as the paper feed tray for slip sheet) Each of the mechanisms 42 operates to press the printing paper P against the paper feed roller 8 as in the first embodiment.

When the print paper P is pressed against the paper feed roller 8 with an appropriate pressure, a command is issued from the control means 76 to rotate the paper feed roller 8 and feed the print paper P from the upper stage of the paper feed tray 37. To do. The printing paper P sent to the paper transport path 14 is transported by the transport roller pair 15, and when the leading end reaches a position where it abuts on the registration roller pair 10, a signal is output from the control means 76 to cause the transport roller pair 15 to move. Be stopped. The registration roller pair 10 that has been stopped rotates in accordance with the rotation of the printing drum 16 and feeds the printing paper P from the paper transport path 12 between the printing drum 16 and the press roller 17. At this time, the leading edge of the printing paper P crosses the paper sensor 13, and the paper sensor 13 outputs a signal, which is input to the RAM 78. The signal input to the RAM 78 is collated by the CPU 77 with the print data stored in the ROM 79, and the CP is checked based on this print data.
A signal is sent from U77 to energize the solenoid 30. By energizing the solenoid 30, the press roller 17 is moved to the second position, and the original image is transferred to the printing paper P fed from the upper stage of the paper feed tray 37. Then, the printing paper P is transferred to the suction conveyance unit 34.
The sheet is conveyed while being stretched, and is discharged onto the sheet discharge tray 35. The press roller 17 is again positioned at the first position as in the first embodiment.

When the print paper P fed from the upper stage of the paper feed tray 37 is discharged onto the paper discharge tray 35, the print paper P as an interleaf paper is then fed from the paper feed tray 7. When the leading edge of the printing paper P sent to the paper transport path 11 reaches a position where it abuts against the registration roller pair 10, a signal is output from the control means 76 and the paper feed roller 8 is stopped.
The registration roller pair 10 which has been stopped rotates in accordance with the rotation of the printing drum 16 to transfer the printing paper P to the paper transport path 1.
2 to feed between the printing drum 16 and the press roller 17.

At this time, a signal is output from the paper sensor 13, this signal is input to the RAM 78, and then the CPU
The print data is collated at 77 with the print data stored in the ROM 79, but this print data is designed not to energize the solenoid 30. Therefore, the press roller 17 does not move while being held at the first position, and the print paper P fed from the paper feed tray 7 passes between the print drum 16 and the press roller 17 and is sucked and conveyed. After being carried to the unit 34, it is discharged onto the paper discharge tray 35.

As described above, the press roller 17 is moved when the printing paper P fed from the printing paper feed tray is printed, and the press roller 17 is printed when the printing paper P fed from the interleaf paper feed tray is printed. By storing in the ROM 79 the print data indicating that the paper is not moved, the printed paper and the unprinted paper are alternately stacked on the paper discharge tray 35. As a result, the excess ink on the printed paper is absorbed by the unprinted paper as the interleaving paper, and the problem of ink show-through is prevented. Further, waste paper can be used as the printing paper P as the interleaving paper.

As a third embodiment, a case of printing in the grouping mode will be described. Prior to printing, the operator sets the original on an image reading device (not shown),
After pressing the plate making start key 82 on the operation panel 66 to wind the plate made master on the outer peripheral surface of the printing drum 16,
Press the grouping key 68. The signal is the CPU 77
Then, the print data is read from the ROM 79, and an instruction is issued to set the number of trays to be used for printing, the designated tray number, the number of groups, and the number of prints for each group on the message display 72. On the other hand, the operator designates the number of trays with the ten keys 73. Here, a case where one tray is selected will be described. Next, the operator selects and designates the tray to be used with the tray selection key 70, sets the number of groups and the number of prints for each group with the ten keys 73, and then presses the start key 74.

Similar to each of the above-described embodiments, the vertical movement mechanism 42 provided in the selected paper feed tray (assuming that the upper stage of the paper feed tray 37 is selected) operates to feed the print paper P to the paper feed roller 8 Press against. The printing paper P is pressed against the paper feed roller 8 with an appropriate pressure, and then conveyed to a position where the paper feed roller 8 and the conveyance roller pair 15 contact the registration roller pair 10.
After that, the printing paper P is sent between the printing drum 16 and the press roller 17 by the registration roller pair 10,
Causes the sensor 13 to output a signal. This signal is RAM7
8 and is collated with print data stored in the ROM 79 by the CPU 77. A signal is sent from the CPU 77 based on the print data, and the solenoid 30 is energized. By energizing the solenoid 30, the press roller 17 is moved to the second position, and the paper feed tray 3
The original image is transferred to the printing paper P fed from the upper stage of 7. This operation is repeated until the number of printed sheets for one group input to the RAM 78 is exhausted.

When the number of printed sheets for one group input to the RAM 78 has been exhausted, the CPU 77 cuts off the power supply to the solenoid 30 and sets the press roller 17 to the first position to set the print paper P to 1 Pass only one piece. After that, the CPU 77 energizes the solenoid 30 again in the same manner as described above, and the printing of the next group is performed. When the number of printed sheets for this group is exhausted again, the CPU 77 cuts off the power supply to the solenoid 30,
Only one sheet of printing paper P is passed while the press roller 17 is positioned at the first position. RAM for the above operation
By storing in the ROM 79 the print data of repeating up to the number of groups input in 78, an unprinted paper is inserted as a slip sheet between each group formed of a plurality of printed papers. It is possible to perform grouping of printed sheets without using a sorting device.

As a fourth embodiment, a case will be described in which, prior to printing, each item is set in the same manner as in the third embodiment, and when the number of trays to be used is set, two trays are selected with the ten keys 73. . Operator selects tray selection key 7
When 0 is selected, the printing paper feed tray and the interleaving paper feed tray are selected and designated, and the start key 74 is pressed. Start key 7
When 4 is pressed, the vertical movement provided in each selected tray (assuming that the upper tray of the paper feed tray 37 is selected as the paper feed tray for printing and the paper feed tray 7 is selected as the paper feed tray for slip sheet) Each of the mechanisms 42 operates to press the printing paper P against the paper feed roller 8 in the same manner as in each of the above embodiments.

The printing paper P fed from the upper stage of the paper feed tray 37 is pressed against the paper feed roller 8 with an appropriate pressure, and then comes into contact with the registration roller pair 10 by the paper feed roller 8 and the transport roller pair 15. Be transported to. After that, this printing paper P
Is sent between the printing drum 16 and the press roller 17 by the registration roller pair 10 and causes the sensor 13 to output a signal. This signal is input to RAM78 and CP
In U77, the print data stored in the ROM 79 is collated. A signal is sent from the CPU 77 based on the print data, and the solenoid 30 is energized. By energizing the solenoid 30, the press roller 17 is moved to the second position, and the original image is transferred to the printing paper P fed from the upper stage of the paper feed tray 37. This operation is repeated until the number of printed sheets for one group input to the RAM 78 is exhausted.

When the number of printed sheets for one group input to the RAM 78 has been exhausted, the CPU 77 cuts off the power supply to the solenoid 30 and positions the press roller 17 at the first position, and then the paper feed tray. Only one sheet of printing paper P, which is an interleaf paper fed from 7, is passed. After that, the CPU 77 again causes the solenoid 30 to operate similarly to the above.
Is energized to print the next group. When the number of printed sheets for this group is exhausted again, C
The PU 77 cuts off the energization of the solenoid 30 and allows only one sheet of printing paper P from the paper feed tray 7 to pass while the press roller 17 is positioned at the first position. By storing in the ROM 79 print data that the above operation is repeated up to the number of groups input to the RAM 78, between each group formed of a plurality of printed sheets,
By inserting unprinted paper as a slip sheet, it is possible to group printed paper without using a grouping device. Further, as the printing paper P as the interleaving paper, waste paper or colored paper can be used.

As a fifth embodiment, prior to printing, each item is set in the same manner as in the fourth embodiment, and when the number of trays to be used is set, two trays are selected with the numeric keypad 73, and The case where the paper moving mode is selected will be described.
The operator selects and designates the printing paper feed tray and the interleaving paper feed tray by the tray selection key 70 according to the instruction of the message display 72. Then, the interleaving sheet moving mode is selected when the interleaf sheet feeding tray (assuming that the upper stage of the sheet feeding tray 37 is selected).

When the slip sheet moving mode is selected, a command is issued from the control means 76 and the shaft 50 is rotated by the rotational force of the motor 44.
The ball screw 45 engraved on the
On the other hand, the paper feed tray 38 moves in the setting direction of FIG. Axis 5
With the rotation of 0, the slit disk 46 also rotates, and the slit sensor 47 counts the slits 53 to detect the movement amount of the paper feed tray 38. The movement amount detected by the movement amount detecting means 54 is input to the RAM 78 and RO is stored in advance.
When compared with the data set in M79 and the movement amount and the set data match, the CPU 77 outputs a movement stop command.

After that, when the start key 74 is pressed,
Each selected tray (the lower tray of the paper feed tray 37 as the paper feed tray for printing is the paper feed tray 3 as the paper feed tray for interleaving paper)
The upper and lower moving mechanisms 42 provided in the upper stage of 7 are respectively operated, and the printing paper P is brought into pressure contact with the paper feed roller 8 in the same manner as in the above-described embodiments.

The printing paper P fed from the lower stage of the paper feed tray 37 is pressed against the paper feed roller 8 with an appropriate pressure, and then comes into contact with the registration roller pair 10 by the paper feed roller 8 and the transport roller pair 15. Be transported to. After that, this printing paper P
Is sent between the printing drum 16 and the press roller 17 by the registration roller pair 10 and causes the sensor 13 to output a signal. This signal is input to RAM78 and CP
In U77, the print data stored in the ROM 79 is collated. A signal is sent from the CPU 77 based on the print data, and the solenoid 30 is energized. By energizing the solenoid 30, the press roller 17 is moved to the second position, and the original image is transferred to the printing paper P fed from the upper stage of the paper feed tray 37. This behavior is
The process is repeated until the number of printed sheets for one group input to the RAM 78 is exhausted.

When the number of printed sheets for one group input to the RAM 78 is exhausted, the CPU 77 cuts off the energization of the solenoid 30 and positions the press roller 17 at the first position, and then the feed tray. Only one sheet of printing paper P as interleaving paper fed from the upper stage of 37 is passed. The printing paper P as a slip sheet discharged onto the paper discharge tray 35 is discharged with its discharge position different from that of the printed paper in a direction orthogonal to the paper discharge direction. Then CPU7
In No. 7, the solenoid 30 is energized again in the same manner as described above, and the printing of the next group is performed. When the number of printed sheets for this group is exhausted again, the CPU 77 cuts off the energization of the solenoid 30 and positions the press roller 17 at the first position, so that the printing paper from the upper stage of the paper feed tray 37 is printed. Only one sheet of paper P passes through, and the paper output tray 35
Discharge on top. By storing in the ROM 79 print data that the above operation is repeated up to the number of groups input to the RAM 78, an unprinted sheet is inserted as an interleaf sheet between each group configured by a plurality of printed sheets,
As a result, printed sheets can be grouped without using a grouping device. Further, as the printing paper P as the interleaving paper, waste paper or colored paper can be used, and printed paper can be easily taken out for each group.

As a sixth embodiment, a case where the sheets are sorted in the sorting mode will be described. Prior to sorting, the operator presses the sorting key 69 on the operation panel 66. The signal is input to the RAM 78, judged by the CPU 77, the print data is read from the ROM 79, and the number of trays used for the message display 72, the designated tray number, the feeding order from each designated tray, and the designated tray. An instruction is given to set the number of sheets to be fed and the required number of divisions. On the other hand, the operator designates the number of trays with the ten keys 73. Then the operator
Use the keypad 73 to select the tray to use with the tray selection key 70.
The number of sheets to be fed is input for each designated tray with, the feeding order is designated with the tray selection key 70, the number of sorting is input with the ten keys 73, and the start key 74 is pressed.

When the start key 74 is pressed, the selected trays (the upper tray of the paper feed tray 37 and the lower tray of the paper feed tray 37 are selected, and the upper tray of the paper feed tray 37 is fed first. The vertically moving mechanism 42 provided (for the designated position) is activated, and the printing paper P is brought into pressure contact with the paper feed roller 8 as in the above embodiments. At this time, not the printing paper P but the paper to be sorted is loaded in each paper feed tray. Printed sheets may be used as the sheets to be sorted.

According to the designated paper feed order, the paper feed tray 37
The sheet fed from the upper stage is pressed against the sheet feeding roller 8 with an appropriate pressure, and then conveyed to a position where the sheet feeding roller 8 and the conveying roller pair 15 contact the registration roller pair 10. After that, the sheet is sent between the printing drum 16 and the press roller 17 by the pair of registration rollers 10 and causes the sensor 13 to output a signal. This signal is input to the RAM 78 and collated with the print data stored in the ROM 79 by the CPU 77. CPU based on this print data
Although a signal is sent from 77, the solenoid 30 is not energized at this time. Therefore, the press roller 17 is still held at the first position, and the image is not transferred to the sheet fed from the upper stage of the sheet feed tray 37, and is directly discharged onto the sheet discharge tray 35. This operation is RAM7
The process is repeated until the number of fed sheets input in 8 is exhausted.

When the number of sheets to be fed for one group inputted to the RAM 78 is exhausted, the CPU 77 stops the sheet feeding roller 8 which feeds the sheet from the upper stage of the sheet feeding tray 37, and the lower stage of the sheet feeding tray 37. The paper feed roller 8 for feeding more paper is rotated. The sheet fed from the lower stage of the sheet feed tray 37 is fed between the printing drum 16 and the press roller 17 by the pair of registration rollers 10 and causes the sensor 13 to output a signal. Then, a signal is sent from the CPU 77, but the solenoid 30 is not energized at this time as well. Therefore, the press roller 17 is still held at the first position, the image is not transferred to the paper fed from the lower stage of the paper feed tray 37, and the paper discharge tray 35 remains as it is.
Discharged on top. This operation is repeated until the number of fed sheets input to the RAM 78 is exhausted. RA operation
By storing print data in the ROM 79, which is repeated until the number of sortings input in M78 is exhausted, the sheets can be sorted without using the sorting device.

[0063]

According to the first aspect of the present invention, when printing is performed by selecting the slip sheet mode, the control means moves every other sheet with respect to the print sheet fed from the sheet feeding device. Since the unprinted paper is sandwiched between the printed papers by activating the means and bringing the printing papers into contact with the outer peripheral surface of the drum by every other press roller, the excess ink adhered to the printed papers Is absorbed by the non-printed sheet as the interleaf sheet, and the show-through can be prevented without lowering the printing efficiency and without providing an extra device.

According to the second aspect of the invention, when the interleaf sheet mode is selected and the printing paper feed tray and the interleaf paper feed tray are designated from the plurality of paper feed trays, respectively, and printing is performed. The control means alternately switches the printing paper feed tray and the interleaving paper feed tray to feed the printing papers one by one, and to the printing papers fed from the printing paper feed tray. Prints the paper fed from the paper feed tray by activating the moving means and stopping the operation of the moving means for the printing paper as the interleaf paper fed from the interleaf paper feed tray. Since the unprinted paper fed from the interleaf paper tray is sandwiched between the paper as interleaf paper, the excess ink that has adhered to the printed paper is absorbed by the unprinted paper as interleaf paper. , Without reducing printing efficiency, and Show-through without providing a minute device can be prevented. In addition, since waste paper can be used as the interleaving paper, the running cost can be reduced.

According to the third aspect of the present invention, when the grouping mode is selected and the number of groups and the number of prints for one group are designated and printing is performed, the control means controls the printing of the first group. Until the end, the moving means is operated, after the printing of the first group is completed, when the paper feeding device feeds one sheet of printing paper as interleaving paper, the operation of the moving means is stopped, and then the printing of the next group is performed. Sometimes, by moving the moving means again, unprinted sheets are sandwiched between the groups, so that grouping can be performed without providing an extra device.

According to the fourth aspect of the present invention, the grouping mode is selected and the printing paper feed tray and the interleaving paper feed tray are designated from a plurality of paper feed trays.
Moreover, when printing is performed by designating the number of groups and the number of prints of each group, the control means performs the feeding from the printing paper feed tray and activates the moving means for the printing of the first group. After printing for the first group, print one sheet of interleaving paper from the interleaving paper tray.
After feeding the sheets and stopping the operation of the moving means,
When printing the next group, by moving the moving means again, between the groups of printed sheets that have been fed from the printing paper tray, there is no printing that has been fed from the interleaf paper tray. Since the sheets are sandwiched as interleaving sheets, grouping can be performed without providing an extra device. Further, by using waste paper or low-grade paper as the interleaving paper, the running cost can be reduced, and by using colored paper as the interleaving paper, it is possible to clarify the division between the groups.

According to the fifth aspect of the present invention, the grouping mode is selected and the printing paper feed tray and the interleaving paper feed tray are designated from a plurality of paper feed trays.
Moreover, when printing is performed by designating the number of groups and the number of prints of each group, the control means performs the feeding from the printing paper feed tray and activates the moving means for the printing of the first group. After the printing of the first group is completed, it is moved by the paper feed tray moving means, and one sheet of print paper is fed as the interleaf paper from the paper feed tray for printing and the paper feed tray for which the paper feed position is different. And the operation of the moving means is stopped, and then when printing the next group,
By operating the moving means again, the unprinted paper fed from the interleaf paper feed tray is displaced between the groups of printed paper fed from the print paper feed tray. Since it is sandwiched as interleaving paper, grouping can be done without providing an extra device, and by using waste paper or low-grade paper as interleaving paper,
The running cost can be reduced, and the use of colored paper as the interleaving paper makes it possible to further clarify the division between the groups.

According to the sixth aspect of the present invention, the sorting mode is selected, the sheet feeding order of the plurality of sheet feeding trays, the number of sheets fed, and the number of sorting are specified respectively, and the sheets are fed from each sheet feeding tray. When sorting the paper, the control means causes the paper to be fed from each paper feed tray according to the designated paper feed order, the number of fed paper sheets, and the number of bins, and the paper fed from each paper feed tray. For example, by stopping the operation of the moving means, the sheets are conveyed sequentially without being printed.
The sheets can be sorted without separately providing a sorting device.

[Brief description of drawings]

FIG. 1 is a schematic side view of a main part of a printing apparatus adopting an embodiment of the present invention.

FIG. 2 is a partial perspective view of a printing unit illustrating an embodiment of the present invention.

FIG. 3 is a diagram of an operation panel illustrating an embodiment of the present invention.

FIG. 4 is a diagram illustrating a control unit that is an embodiment of the present invention.

FIG. 5 is a side sectional view of a paper feed tray illustrating an embodiment of the present invention.

FIG. 6 is a diagram illustrating a movement amount detection unit that is an embodiment of the present invention.

FIG. 7 is a diagram illustrating a vertical movement mechanism that is an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printing device 2,6 Paper feeding device 7,37 Paper feeding tray 16 Printing drum 17 Press roller 27 Moving means 76 Control means

Claims (6)

[Claims] 1. A press roller rotatably provided between a rotatable drum, a first position which is an initial position separated from the outer peripheral surface of the drum, and a second position which is in contact with the outer peripheral surface. A sheet feeding device that feeds printing paper, and a moving unit that reciprocates the press roller between the first position and the second position. In a printing apparatus having a slip sheet mode for inserting a slip sheet, when printing is performed by selecting the slip sheet mode, every other sheet of the print sheet fed from the sheet feeding device is printed. A printing apparatus comprising control means for operating a moving means. 2. The sheet feeding device has a plurality of sheet feeding trays, selects the interleaf sheet mode, and selects a printing sheet tray and an interleaf sheet tray from each of the sheet trays. When printing is specified, the printing paper feed tray and the interleaving paper feed tray are alternately switched to feed the printing papers one by one, and the papers are fed from the printing paper feed tray. The moving means is operated for the sent printing paper, and the operation of the moving means is stopped for the printing paper as the interleaving paper fed from the interleaf paper feed tray. The printing apparatus according to claim 1, further comprising a control unit. 3. A rotatable drum, a press roller movably provided between a first position, which is an initial position separated from the outer peripheral surface of the drum, and a second position in contact with the outer peripheral surface. A sheet feeding device for feeding a printing sheet, and a moving unit for reciprocating the press roller between the first position and the second position. In a printing apparatus having a grouping mode in which a predetermined number of sheets are printed and interleaving sheets are inserted between groups of printed sheets of the predetermined number of sheets, the grouping mode is selected, and the number of groups and one group When printing is performed by designating the number of prints respectively, the moving means is operated until the printing of the first group is completed, and after the printing of the first group is completed, the paper feeding device detects the interleaving paper. A printing device comprising: a control unit that stops the operation of the moving unit when one sheet of the printing paper is fed, and then operates the moving unit again when printing the next group. . 4. The sheet feeding device has a plurality of sheet feeding trays, the grouping mode is selected, and a sheet feeding tray for printing and a sheet feeding tray for interleaving are respectively selected from the sheet feeding trays. When printing is performed by designating the number of groups and the number of prints of one group respectively, when printing the first group, paper is fed from the printing paper feed tray and the moving means is operated. After the printing of the first group is completed, one sheet of the printing paper as the interleaving paper is fed from the interleaving paper feed tray and the operation of the moving unit is stopped, and thereafter, at the time of printing of the next group. 4. The printing apparatus according to claim 3, further comprising control means for activating the moving means again. 5. The grouping mode, wherein the sheet feeding device has a plurality of sheet feeding trays, and a sheet feeding tray moving means for moving the sheet feeding trays in a direction orthogonal to the sheet feeding direction. When selecting and selecting the paper feed tray for printing and the paper feed tray for interleaving paper from each of the paper feed trays, and specifying the number of groups and the number of prints of one group respectively, when performing printing, For the printing of the group, the paper is fed from the printing paper feed tray and the moving means is operated, and after the printing of the first group is finished, the paper is moved by the paper feed tray moving means and the printing paper feed is performed. One sheet of the printing paper as the interleaving paper is fed from the interleaving paper feeding tray whose paper feeding position is different from that of the paper tray, and the operation of the moving means is stopped, and then the next group The printing apparatus according to claim 3, further comprising a control unit that operates the moving unit again at the time of printing. 6. A rotatable drum, and a press roller movably provided between a first position, which is an initial position separated from the outer peripheral surface of the drum, and a second position in contact with the outer peripheral surface. A sheet feeding device having a plurality of sheet feeding trays for feeding sheets, and a moving unit for reciprocating the press roller between the first position and the second position. A printing apparatus having a sorting mode for sequentially feeding a predetermined number of sheets of paper from each of the paper feed trays, selecting the sorting mode, feeding order from each of the paper feed trays, When the number of sheets and the number of sorting sheets are designated and the sheets fed from the respective sheet feeding trays are sorted, the sheets are fed from the respective sheet feeding trays according to the designated sheet feeding order, the number of sheets fed and the sorting number. , And each of the above For the paper fed from the paper tray, the printing apparatus characterized by comprising a control means for stopping the operation of said moving means.