JPH09188057A - Perfecting press - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a perfecting press which can automatically print both faces of a printing paper. SOLUTION: A processed base paper for screen printing is provided over the outer periphery of a printing drum 3. A paper feed roller 21 feeds a printing paper P to the printing drum 3. A press roller 26 presses the fed printing paper P against the drum 3 to perform printing. The printed paper P passes through a transfer prevention mechanism 28 and is put into a reversing means 30 by switching a switching means 35. The paper P whose top and bottom faces are reverse to each other enters a primary delivery part 25. The part 25 is elevated and set at a paper feed table 19. The paper P whose bottom face is printed is sent again to the drum 3 through the roller 21 so that the top face of the paper P is printed. The means 35 is changed over and the paper is delivered to a second delivery part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double-sided printing apparatus capable of printing on both sides of printing paper.

[0002]

2. Description of the Related Art FIG. 9 schematically shows the structure of a general stencil printing machine. At the center of the printing device is a print drum 100 that rotates about its central axis. A part of the peripheral wall of the printing drum 100 is ink permeable. There is an ink supply means inside the print drum. In the figure, on the right side of the printing drum 100, there is a plate making unit 101 having a thermal head, a platen roll, a roll-shaped stencil printing base paper, and a cutter. In the figure, on the left side of the printing drum 100, there is a plate discharging means 102 for accommodating the used stencil printing base paper peeled from the printing drum 100. In the figure, above the print drum 100, there is a document reading unit 103 for reading image information of a document. Further, in the lower part of the printing apparatus, below the plate discharging means 102, there is a paper feeding means 104 for sequentially feeding a stack of sheets stacked on a paper feeding table to the printing drum from the topmost sheet. Printing drum 100
Below the table, there is a pressing unit 105 provided with a press roller for performing printing by sandwiching the printing paper supplied from the paper feeding unit 104 with the printing drum 100 and carrying the printing paper. In the vicinity of the printing drum 100, there is a peeling unit 106 that includes a separating claw and an air blower and that peels the printed paper from the printing drum. Adjacent to the peeling unit 106, there is a conveying unit 107 that conveys a sheet that has been printed and peeled from the printing drum 100. Next to the conveying means 107, there is a paper discharge stacker 108 that receives and stacks the printed and peeled paper from the printing drum 100.

The used stencil printing base paper is a plate discharging means 102.
Is stored in. The document reading unit 103 reads the document information, and the thermal head of the plate making unit 101 forms a perforated image on the stencil printing base paper based on the document information. The stencil sheet that has been prepressed is wound around the printing drum 100 by holding the leading end of the stencil sheet with clamping means and rotating the printing drum 100. After that, the sheet sent from the sheet feeding unit 104 is pressed by the pressing unit 105.
Is pressed against the printing drum 100 by
The ink inside is transferred onto the paper to perform stencil printing.

[0004]

In principle, the above-mentioned stencil printing machine can print only one side of the printing paper. If printing is to be performed on both sides of the printing paper by the stencil printing machine, the user who uses the printing machine flips over the printing paper once printed, and the paper feeding means 104 in FIG.
It is necessary to load it on the printer and then print again. At this time,
The user of the apparatus discharges the paper stacker 1 so that the printing paper printed on one side is smoothly supplied to the printing apparatus without any trouble.
After the print sheets stacked on the 08 are rearranged, they must be stacked on the sheet feeding unit 104 again. Since a certain technique is required to arrange the printing papers stored in the paper discharge stacker 108 into a state suitable for re-feeding, not everyone can use the stencil printing machine for double-sided printing, and The users of are limited to some extent.

It is an object of the present invention to provide a double-sided printing device capable of automatically printing on both front and back sides of printing paper regardless of the skill of the user of the device.

[0006]

According to a first aspect of the present invention, there is provided a double-sided printing device in which a printing plate is provided on an outer peripheral surface of the printing drum, the printing drum rotating around its own central axis, and printing paper on the printing drum. Next to the paper feeding means for supplying, the pressing means for pressing the printing paper supplied by the paper feeding means against the printing drum to print on the printing paper, and the printing drum for ejecting the printed printing paper And a reversing means for receiving printed printing paper ejected from between the printing drum and the pressing means, reversing the upper surface and the lower surface of the printing paper, and ejecting from the ejection port, the printing drum and the pressing means. The switching means for switching whether or not the printed printing paper discharged from the space enters the reversing means and the discharge means of the reversing means are provided adjacent to the upper and lower surfaces of the reversing means. A first paper discharging unit that receives the rolled printed printing paper and supplies it again to the paper feeding unit, and a printed paper that has not entered the reversing unit after being discharged from between the printing drum and the pressing unit. And a second paper ejection unit for receiving the printing paper.

A double-sided printing apparatus according to a second aspect is the double-sided printing apparatus according to the first aspect, in which printing is performed on a printed printing sheet between the printing drum and the pressing means and the reversing means. It is characterized in that a re-transfer prevention mechanism is provided to prevent transfer of the ink to another.

A double-sided printing apparatus according to a third aspect is the double-sided printing apparatus according to the second aspect, in which the printed printing sheet received by the first sheet discharging section is transferred to the printing drum by the sheet feeding means. It comprises a moving means for moving the first paper discharging portion to the paper feeding means for feeding again.

A double-sided printing device according to a fourth aspect is the double-sided printing device according to the third aspect, wherein the paper feeding means includes a paper feed tray and a paper feed roller, and the paper feed tray includes a printing sheet. The sheet feed table is movable between a first state in which the sheet is held and a second state in which the print sheet is not held and receives the first sheet discharge unit. A single sheet for sending the printing paper held by the paper feed tray in the state or the printing paper held by the first paper discharge unit received by the paper feed tray in the second state to the print drum. A sheet feeding roller, the discharge port of the reversing unit and the first sheet discharging unit are set below the sheet feeding table, and the moving unit prints the first sheet discharging unit from the discharging port. The lower position for receiving the paper and the first paper ejection unit bring the paper feed table into the second state Between the parts position, and is configured to move the first sheet discharge unit.

A double-sided printing device according to a fifth aspect is the double-sided printing device according to the third aspect, wherein the paper feeding means is
A paper feed table on which the print paper is placed, a first paper feed roller for feeding the print paper from the paper feed tray to the print drum, and a reversed printed print received by the first paper discharge unit. A second paper feed roller for feeding a sheet to the printing drum, and the moving means moves the first paper discharge unit between the vicinity of the discharge port and the second paper feed roller. It is configured to let.

A double-sided printing apparatus according to a sixth aspect is the double-sided printing apparatus according to the first aspect, in which a print selection signal for selecting double-sided printing or single-sided printing is input from the outside, and double-sided printing is performed by the print selection signal. If selected,
After switching the switching means to the reversing means side, primary printing is performed on one side of the number of printing sheets designated from the outside, and then the switching means is switched to the second paper discharging portion side and When secondary printing is performed on the printing paper that has been inverted by the inversion means and received by the first paper discharge unit, and single-sided printing is selected by the print selection signal,
After the switching unit is switched to the side of the second sheet discharge unit, a control unit is provided for performing control so as to perform primary printing on one side of the number of printing sheets designated from the outside.

A double-sided printing device according to a seventh aspect is the double-sided printing device according to the sixth aspect, wherein the printing drum is replaceable according to a printing color, and the control means selects double-sided printing. After the print selection signal is input, a print color selection signal for selecting double-sided same-color printing or double-sided color printing is input from the outside, and when the double-sided color printing is selected by the print color selection signal, the primary The control means controls the secondary printing only when the printing drum is replaced with another printing drum having a different printing color after printing.

A double-sided printing device according to an eighth aspect is the double-sided printing device according to the sixth aspect, wherein the double-sided printing device forms a plate of a desired original document, and a printing plate from the printing drum. And a printing original selection signal for selecting double-sided original document printing or double-sided original document printing is externally input to the control unit after a print selection signal for selecting double-sided printing is input to the control unit. When the two-sided document printing is selected by the print document selection signal, the plate discharging unit removes the plate from the printing drum and the plate making unit creates a new plate after the primary printing. The control means controls the secondary printing only when the secondary printing is performed on the printing drum.

A double-sided printing device according to a ninth aspect is the double-sided printing device according to the sixth aspect, in which the printing drum is replaceable according to a printing color, and plate making means for producing a desired original plate. And a plate discharge unit for removing the plate from the printing drum, and the control unit selects double-sided same-color printing or double-sided different-color printing after a print selection signal for selecting double-sided printing is input. A print color selection signal and a print original selection signal for selecting both-sided original document printing or both-sided original document printing are input from the outside, and both-sided individual color printing is selected by the print color selection signal, and by the print original selection signal. When double-sided original printing is selected, the printing drum is replaced with another printing drum having a different printing color after the primary printing, and then a new printing plate created by the plate making means is loaded on the printing drum. Vignetting, said control means so as to then perform the secondary printing is characterized by performing control.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described with reference to FIGS. The double-sided printing device 1 is a printing device which can use both of the stencil printing base paper and the printing plate as a printing plate and can print on both sides of the printing paper according to the principle of stencil printing. The printing drum 3 is provided inside the housing 2 of the printing apparatus 1.
Is stored. The printing drum 3 has a cylindrical peripheral wall at least a part of which is permeable to ink, and is rotated about its central horizontal axis by driving means (not shown). In FIG. 1, the printing drum 3 rotates counterclockwise.

A clamp base 4 is provided on the outer peripheral surface of the peripheral wall of the printing drum 3. The clamp base 4 has a rotation axis parallel to one generatrix of the printing drum 3. A clamp plate 5 is rotatably attached to the rotary shaft, and the tip of the stencil printing base paper can be sandwiched and fixed between the clamp plate 5 and the clamp base 4.

Inside the printing drum 3, there is an ink supply means 6 for supplying a fixed amount of ink to the inner peripheral surface of the peripheral wall. The ink supply means 6 includes a squeegee roller 7 that is in contact with the peripheral wall and rotates in synchronization with the printing drum 3, and a doctor roller 8 that is arranged in the squeegee roller 7 with a predetermined gap.
It has a distributor 9 for supplying ink between the squeegee roller 7 and the doctor roller 8. The ink propagates through the gap between the squeegee roller 7 and the doctor roller 8 on the peripheral surface of the squeegee roller 7, and is supplied to the inner surface of the peripheral wall of the printing drum 3 in a constant amount. At the time of printing, the squeegee roller 7 rotates in synchronization with the printing drum 3, so that a swirl of ink is formed between the squeegee roller 7 and the doctor roller 8. By detecting the size of this ink vortex,
It is possible to detect an increase or decrease in ink. When the size of the ink vortex is reduced, the ink is carried from an ink storage unit (not shown), and the ink is supplied from the distributor 9 to the ink vortex.

The ink color of the ink supply means 6 is determined for each print drum 3, and when it is desired to change the ink color, the print drum 3 is replaced. That is, in the double-sided printing device 1 of this example, the printing drum 3 can be replaced.

An automatic document reading device 10 is provided on the upper surface of the housing 2 of the present device. The document automatic reading device 10 automatically reads a document set at a predetermined position of the device,
Output as manuscript information.

In FIG. 1, to the right of the top of the printing drum 3,
There is a plate making means 11. The plate making means 11 is a roll-shaped stencil printing base paper S rotatably supported at a predetermined position, a thermal head 12 and a platen roll 13 as plate making elements for punching the stencil printing base paper S by heat, The stencil sheet S has a carrying roller 14 for carrying the stencil sheet S, and a cutter 15 for cutting the stencil sheet S thus prepared.

In FIG. 1, to the left of the top of the printing drum 3,
There is a plate discharging means 16. The plate discharge means 16 has a plate discharge box 17 for storing the used stencil printing base paper S and a conveying means 18 for transferring the used stencil printing base paper S into the plate discharge box 17.

In FIG. 1, to the left of the bottom of the printing drum 3,
There is a paper feeding means 19. The sheet feeding means 19 of this example is the sheet feeding table 2
0 and a paper feed roller 21 provided at one place. The paper feed tray 20 is provided in the paper feed port 2 a formed in the housing 2. As shown in FIGS. 2 and 4, the paper feed tray 20 includes a pair of paper feed plates 22 and 22 arranged at a predetermined interval. The outer edge of each paper feed plate 22 is rotatably supported by two support shafts 23 parallel to the paper feed direction. As shown in FIG. 2, each paper feed plate 22 is
It is supported in a horizontal state by the supporting portion 24 and faces each other with a predetermined interval smaller than the width of the printing paper. This state is called the first state. In the first state, the paper feed tray 20
A printing paper P is placed on top of. Only when there is no printing paper P on the paper feed tray 20, if each paper feed plate 22 is pushed up from below as shown in FIG.
Rotate upward about 90 from the first state by about 90 degrees,
It can be in a substantially vertical position. This state is called the second state.

The paper feed roller 21 feeds the print paper P on the paper feed tray 20 in the first state toward the print drum 3.

As shown in FIG. 1 and FIG.
Below the 0, a primary paper discharge unit 25, which is a first paper discharge unit, is provided. The primary paper discharge unit 25 is provided in the paper discharge port 2b formed in the housing 2. The printing paper P having one side printed by the printing drum 3 (printing paper P that has undergone primary printing) is discharged to the primary paper discharge unit 25. The primary paper discharge unit 25 can be moved up and down between a lower position and an upper position by a moving unit (not shown). The lower position is a position where the primary paper ejecting unit 25 receives the printing paper P on which the primary printing has been completed. At the upper position, the primary paper discharge unit 25 that is moved up by the moving means pushes up the paper feed plate 22 and moves the paper feed plate 22 to the second position.
It is the position to be set to the state of.

The paper feed roller 21 transfers the printing paper P (primarily printed printing paper P) on the primary paper ejecting section 25 received by the paper feed tray 20 in the second state, to the printing drum 3. Send in the direction.

Below the printing drum 3, a press roller 26 as a pressing means is provided so as to be able to move up and down.
The press roller 26 presses the printing paper P supplied from the paper feeding means 19 against the printing drum 3, and conveys the printing paper P while sandwiching it between the printing drum 3 and transferring the ink from the printing drum 3 to the printing paper P. Perform stencil printing.

In FIG. 1, on the right side of the bottom of the printing drum 3 from which the printing paper P is discharged, there is a separation claw 27 for peeling the printed paper from the printing drum 3. A rearrangement prevention mechanism 28 is provided adjacent to the separation claw 27. The retransfer prevention mechanism 28 prevents the printing ink on the printed printing paper P that has been peeled from the printing drum 3 from transferring to other components of the apparatus, other printing paper P, or the like. The retransfer prevention mechanism 28 removes excess printing ink on the printing paper P,
Alternatively, it has a function of drying or coating the printing paper P. The re-metastatic mechanism 2 of this example illustrated in FIG.
Reference numeral 8 includes a pair of rollers that conveys the printing paper P between them, and a coating unit that coats the retransfer prevention treatment liquid on at least one of the pair of rollers.

A reversing means 30 is provided on the discharge side of the retransfer prevention mechanism 28. The inverting means 30 includes a bending portion 31.
It has a conveyance path 31 provided with a and a plurality of pairs of conveyance rollers 32 that convey the printing paper P along the conveyance path 31. The reversing unit 30 receives the printed printing paper P ejected from the re-transferring mechanism 28, reverses the upper surface and the lower surface thereof, and ejects the printing paper P in a direction opposite to the direction in which the printing drum 3 ejects the printing paper P. Discharge from the outlet. Reversing means 30
The discharge port 33 is provided near the primary discharge unit 25.

At the entrance of the reversing means 30, a switching means 35 for switching whether or not the printed printing paper P discharged from the retransfer prevention mechanism 28 enters the reversing means 30.
Is provided. The switching means 35 of this example has a claw-shaped member that is swingable within a predetermined angle range.
In FIG. 1, when the switching unit 35 is set to the limit position in the clockwise direction to reach the angle for receiving the print sheet P, the print sheet P is introduced into the reversing unit 30 and set to the limit position in the counterclockwise direction to print. When the print sheet P becomes substantially horizontal in the conveying direction, the print sheet P is guided to the secondary sheet discharge unit 36 described later.

Next to the reversing means 30, a second paper ejection section which is a second paper ejection section for receiving the printed printing paper P which has not been admitted to the reversal means 30 after being ejected from the retransfer mechanism 28. A paper unit 36 is provided.

The operation of the double-sided printing device 1 will be described. The procedure for plate making will be described. The document to be printed is set in the document automatic reading device 10 and the document information is read.
In the plate making means 11, the thermal head 12 and the platen roll 13 are driven based on the document information, and the image of the document is punched on the stencil printing base paper S wound in a roll shape. The leading edge of the stencil printing base paper S on which the image is punched is sandwiched between the clamp plate 5 and the clamp base 4 of the printing drum 3. In FIG. 1, the printing drum 3 rotates in the direction of arrow A, and the stencil printing base paper S is wound around the outer circumference of the printing drum 3. In the state where the stencil printing base paper S is wound around the outer circumference of the printing drum 3, the cutter 15 in the plate making means 11 is used.
Cuts the stencil printing base paper S.

The printing procedure will be described. As shown in FIGS. 1 and 2, a desired number of printing sheets P are stacked on the paper feed tray 20 in the first state, and the printing start switch is turned on. A power motor (not shown) rotates the paper feed roller 21, and the print paper P is conveyed to the vicinity of the print drum 3. At the same time, the power drum causes the printing drum 3 to rotate in the direction of arrow A in FIG. When the printing paper P approaches the printing drum 3, the press roller 26 also approaches the printing drum 3, and the printing paper P is conveyed while being sandwiched between the printing drum 3 and the pressing roller 26. The ink in the printing drum 3 is transferred to the printing paper P through the peripheral wall of the printing drum 3 and the perforation portion of the stencil printing base paper S, whereby a printing image corresponding to the image of the original is formed on the printing paper P. .

The printing drum 3 rotates once and the press roller 2
When 6 reaches the non-printable area of the print drum 3, the press roller 26 descends and separates from the print drum 3. The printing paper P is separated from the printing drum 3 by the separating claw 27 and is conveyed to the retransfer preventing mechanism 28.

As shown in FIG. 1, the switching means 35 is
The print sheet P is set at a position where it is guided to the reversing unit 30. The printing paper P ejected from the re-transferring mechanism 28 passes through the reversing unit 30, the upper surface and the lower surface are turned upside down, and is ejected to a position below the paper feed table 20 and accumulated in the primary paper ejection unit 25. The printing paper P is stacked on the primary paper ejection unit 25 with the printed surface facing down.

As described above, all of the printing paper P on the paper feeding table 20 is printed. A desired number of printing papers P, one side of which has been printed, are stacked on the primary paper discharge unit 25 with the printed side facing down. Here, as shown in FIGS. 3 and 4, the primary sheet discharge unit 25 is moved to the upper position by the moving means, and the sheet feeding plate 22 of the sheet feeding tray 20 in the first state is lifted to the second state. And

The printing paper P of the primary paper discharge unit 25 set to the upper position is sent out to the printing drum 3 by the paper feeding roller 21, and the unprinted surface is subjected to secondary printing. At this time, as shown in FIG. 3, the switching means 35 is set so as to close the entrance of the reversing means 30. As a result, the printing paper P on both sides of which has been printed is discharged to the secondary paper discharge unit 36 and stored without entering the reversing unit 30.

According to this example, the printing paper P to be secondarily printed
Immediately after the primary printing, the sheets are reversed and stacked on the primary paper ejection unit 25, and the primary paper ejection unit 25 is conveyed to the paper feeding means 19 and directly fed to the printing drum 3 by the paper feeding roller 21. Therefore, the conveyance path of the printing paper P supplied to the printing drum 3 does not greatly bend, and has a simple shape along a substantially linear direction. Compared with the case where a mechanism is adopted in which the printing paper P that has been subjected to the primary printing is stacked with the printing surface facing upward, and is inverted and sent out to the printing drum 3 immediately before the secondary printing, this example is Printing paper P for the printing drum 3
This has the advantage that the structure of the conveyance path is simple, and it is less likely that conveyance defects such as image stains, conveyance timing deviations, and clogging will not occur. In order to obtain such an advantage, in order to adopt the mechanism for processing the printing paper P immediately after the primary printing by the reversing means 30, a means for preventing the non-dried primary printing ink from adhering to each part of the apparatus is taken. Although it has to be mentioned, in the present example, the printed sheet P which has been printed is processed by the re-transferring mechanism 28, so that the reversing means 30 is provided adjacent to the ejection side of the printing drum 3.
There is no problem in simplifying the structure of the printing drum 3 on the paper feed side.

FIG. 5 shows the configuration of the control means 51 in the first embodiment of the present invention. The control means 51 can be constituted by a microcomputer, and the CPU 52
It has a ROM 54, a RAM 55, and an I / O interface 53. The ROM 54 stores the sequence program for the printing process, and the RAM 55 stores the data necessary for the sequence program.

The input side of the I / O interface 53 has a print selection signal 61 for selecting double-sided printing or single-sided printing.
A print color selection signal 62 for selecting double-sided same-color printing or double-sided different-color printing, and a print-original selection signal 63 for selecting double-sided same-side original printing or double-sided different-side original printing. These signals are input by the operator by an input means such as a keyboard (not shown).

On the output side of the I / O interface 53, a display section 71 for displaying the state of the apparatus and an inverting means 30.
A switching unit driving unit 72 that drives the switching unit 35 that takes in the printing paper P, a printing motor driving unit 73 that drives a power motor for printing, and the automatic document reading apparatus 1
A reading processing unit 74 for reading an original document at 0, a plate making processing unit 75 for making the plate making unit 11 perform plate making processing, and a plate discharge processing unit 76 for making the plate discharging unit 16 carry out plate discharge processing are respectively connected.

FIG. 6 is a flow chart showing a control procedure of the control means 51 in the first embodiment of the present invention. When the device is activated, the control means 51 asks the user of the device via the display unit whether to perform "double-sided printing" or "single-sided printing" (S1). Here, the user inputs a print selection signal 61 for selecting double-sided printing or single-sided printing by the input means. When “single-sided printing” is selected, the control unit 51 sets the switching unit 35 to the state shown in FIG. 3 via the switching unit driving unit 72. The control unit 51 displays on the display unit 71 so as to input the number of prints from the input unit. When the number of prints is input, the control unit 51 drives the print motor drive unit 73 to print.

When the user of the apparatus selects "double-sided printing", the control means 51 sets the switching means 35 to the state shown in FIG. 1 via the switching means drive section 72. Next, the control means 51 “prints with the same color on both sides” via the display unit.
Ask the user of the device whether to print with different colors on both sides (S2). Further, ask the user of the device whether to "print on both sides of the same document" or "print on both sides of different document" (S
3).

When the user selects "two-sided same color" or "two-sided same document", the control means 51 drives the switching means after the number of print sheets P (x sheets) designated by the user are primarily printed. The switching means 35 is set to the state shown in FIG. The primary paper output unit 25 that has received the printing paper P that has undergone primary printing is moved to the upper position, and the paper feed plate 22 of the paper feed tray 20 is opened. The printing paper P whose lower surface is primarily printed is sent to the printing drum 3 by the paper feed roller 21, and secondary printing is performed again on x printing papers P.

When the "same color on both sides" and the "original on both sides different" are selected, the primary printing is performed by the same control as the above-described step, and the primary sheet discharge section 25 is moved to a position above the sheet discharge tray. After that, the reading processing unit 74 and the plate discharge processing unit 76
And driving the plate making processing unit 75 to read a new original,
Discard used plates and perform plate making process based on newly read originals. After that, if the printing paper P of the x sheets of the primary ejecting unit 25 that has been primary-printed is secondarily printed, double-sided printing can be performed using a document having the same color on both sides and different sides.

When "same original on both sides" is selected for "different colors on both sides", when the stencil sheet S is first made,
The manuscript information is stored in the RAM 55 of the control means 51.
Next, the same control as the above step is performed. However, a new original is not read in the above process. When the primary printing is completed, the user of the apparatus is instructed via the display unit to replace the printing drum 3. After that, it is confirmed that the operator has replaced the print drum 3 with the print drum 3 of ink of a desired color, and the original image information stored in the RAM 55 is used to print the same image data as the image data previously made by stencil printing. Plate-making on the base paper S. Then, subsequent secondary printing is performed in the same manner.

If "two-sided different color" is selected as "two-sided different original", after the printing drum 3 is replaced during the process,
A new original reading process is performed, the new original is punched on the stencil printing base paper S, the stencil printing base paper S is wound around the replaced printing drum 3, and secondary printing of x sheets is performed.

According to this example, double-sided printing or single-sided printing, double-sided same-color printing or double-sided different-colored printing, double-sided same original printing or double-sided different original printing can be freely selected, and the primary printing paper P can be selected. It can be automatically used for secondary printing without the operator having to handle it by hand, and double-sided printing can be performed with high efficiency.

A second embodiment of the present invention will be described with reference to FIG. The same components as those in the first embodiment are designated by the same reference numerals as those in FIG. 1 and their description is omitted. The paper feeding means 80 of this example includes a paper feed table 81 on which the print paper P is placed, a first paper feed roller 82 for supplying the print paper P on the paper feed table 81 to the print drum 3, and a primary ejection. The second paper feed roller 83 is provided for supplying the reversed printed printing paper P received by the paper unit 25 to the printing drum 3.

Moving means 84 for moving the primary sheet discharging section 25
Can move the primary paper discharge unit 25 between the vicinity of the discharge port 33 set below the retransfer prevention mechanism 28 and the second paper feed roller 83. In this example, a part of the moving means is constituted by a belt transport mechanism in which the transport belt 86 is wound around at least a pair of pulleys 85, 85. The conveyor belt 86 is provided with a protrusion 86 a, and the protrusion 86 a engages with the primary paper discharge unit 25. When the transport belt 86 moves, the projection 86a pushes and moves the primary paper discharge unit 25. In addition, the other part of the moving unit 84 can arbitrarily move up and down the primary paper discharge unit 25 that is transported below the second paper feed roller 83 by the transport belt 86.

When the double-sided printing device 1 of this example operates, first, the first paper feed roller 82 conveys the printing paper P to the printing drum 3 and performs the primary printing on one surface of the printing paper P. The printing paper P that has undergone the primary printing and is ejected has a re-transfer prevention mechanism 28.
Pass through. The switching unit 35 opens the entrance of the reversing unit 30, and the printing paper P passing through the retransfer preventing mechanism 28 enters the reversing unit 30. The printing paper P on which one surface is printed is inverted so that the printing surface faces down, and is stored in the primary paper ejection unit 25. When the designated number of print sheets P are accumulated in the primary paper output unit 25, the printing of the apparatus is temporarily stopped. The primary discharge unit 25 is moved to the area indicated by the chain line in the figure by the conveyor belt 86 of the moving unit 84, and further moved up by the moving unit to be set at the position of the second paper feed roller 83. Then, the reversed printing paper P of the primary paper discharge unit 25
Are sent to the print drum 3 by the second paper feed roller 83. Secondary printing is performed on the other surface of the printing paper P by the printing drum 3 and the press roller 26. The printing paper P that has been secondarily printed and ejected passes through the retransfer prevention mechanism 28. The switching unit 35 closes the entrance of the reversing unit 30, and the print paper P that has passed through the retransfer prevention mechanism 28 is discharged to the secondary paper discharge unit 36 and stored therein.

A third embodiment of the present invention will be described with reference to FIG. The same components as those in the first and second embodiments are designated by the same reference numerals as those in FIG. 7 and their description is omitted.
In this example, when a predetermined number of printing sheets P that have undergone primary printing are stacked on the primary paper discharge unit 25, the primary paper discharge unit 25 is set in the area B below the paper feed unit 19 by the moving unit 84. . The primary paper discharge unit 25 is raised by a moving unit (not shown) and set at the paper feeding position in the paper feeding unit 19. Subsequent operations are the same as those in the above-mentioned examples.

In the above-described embodiments, the stencil printing apparatus using the stencil printing base paper as the printing plate is illustrated, but the double-sided printing apparatus of the present invention can be applied to a printing apparatus of a principle other than the stencil printing. .

[0053]

According to the present invention, it is possible to automatically print on both sides of a printing paper simply by placing the printing paper on the paper feeding means and starting printing. It is not necessary for the user of the printing apparatus to re-align the print sheets that have been ejected once and arrange them again in the paper feeding means. Therefore, double-sided printing can be performed with higher efficiency than printing using a conventional printing device.

Further, when the printing on one side is completed, the printing process is temporarily interrupted, and the printing drum is replaced or a new original is made, so that it is possible to print the original on both sides or print the colors on both sides. Become.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a first embodiment of the present invention, showing a state during primary printing.

FIG. 2 is a left side view of FIG.

FIG. 3 is a cross-sectional view showing the first embodiment of the present invention, showing a state during secondary printing.

FIG. 4 is a left side view in FIG. 3;

FIG. 5 is a block diagram showing a configuration of control means in the first exemplary embodiment of the present invention.

FIG. 6 is a flowchart showing the control procedure of the control means in the first embodiment of the invention.

FIG. 7 is a cross-sectional view showing a second embodiment of the present invention.

FIG. 8 is a sectional view showing a third embodiment of the present invention.

FIG. 9 is a diagram showing a general configuration of a conventional stencil printing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Double-sided printing device 3 Printing drum 11 Plate making means 16 Plate discharging means 19 Paper feeding means 20 Paper feeding table 21 Paper feeding roller 25 Primary paper discharging section which is the first paper discharging section 26 Press roller as pressing means 28 Retransfer prevention mechanism 30 Reversing Means 33 Reversing Means Discharge Ports 35 Switching Means 36 Secondary Discharge Units that are Second Discharge Units 51 Control Means 80 Paper Feeding Means 81 Paper Feeding Tables 82 First Paper Feeding Rollers 83 Second Paper Feeding Roller 84 moving means

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Claims (9)

[Claims] 1. A printing drum having a printing plate provided on an outer peripheral surface thereof, the printing drum rotating around a central axis of the printing drum, a paper feeding unit for feeding a printing paper to the printing drum, and a printing process supplied by the paper feeding unit. A pressing unit that presses a sheet of paper against the printing drum to perform printing on the printing sheet, and a unit that is provided next to the printing drum from which the printed printing sheet is discharged, and is discharged from between the printing drum and the pressing unit. And a reversing means for reversing the upper surface and the lower surface of the printed printing paper and ejecting it from the discharge port, and the printed printing paper ejected between the printing drum and the pressing means is the reversing means. Switching means for switching whether to enter or not, and a paper feeding hand which is provided next to the discharge port of the reversing means and receives printed printing paper whose upper surface and lower surface are reversed by the reversing means. And a second paper discharging unit that receives printed printing paper that has not entered the reversing unit after being discharged from between the printing drum and the pressing unit. Double-sided printing device. 2. A re-transfer prevention mechanism is provided between the printing drum and the pressing means, and the reversing means to prevent transfer of the printing ink on the printed printing paper to another. The double-sided printing device according to claim 1. 3. The first paper discharging unit is moved to the paper feeding unit in order to supply the printed printing paper received by the first paper discharging unit to the print drum by the paper feeding unit again. The double-sided printing device according to claim 2, further comprising moving means for moving the same. 4. The paper feed means comprises a paper feed table and a paper feed roller, wherein the paper feed table holds a print sheet in a first state and does not hold the print sheet in the first discharged sheet. A sheet feeding table movable between a second state for receiving a set and the sheet feeding roller in the first state, the printing sheet held by the sheet feeding table, or the second state; A single paper feed roller that sends the print paper held by the first paper discharge unit received by the paper feed tray to the print drum, and the discharge port of the reversing unit and the first paper discharge roller. Section is set below the paper feed tray, and the moving means sets the first paper discharge tray to a lower position where the first paper discharge tray receives print paper from the discharge port, and the first paper discharge tray moves the paper feed tray to the paper feed tray. 4. The configuration according to claim 3, wherein the first paper discharge unit is moved between the upper position in which the second state is set. Double-sided printing apparatus. 5. The paper feed unit, a paper feed table on which the print paper is placed, a first paper feed roller for supplying the print paper on the paper feed tray to the print drum, and the first paper discharge unit. A second paper feed roller for feeding the reversed printed printing paper received by the unit to the printing drum, the moving means comprising:
The double-sided printing apparatus according to claim 3, wherein the first paper discharge unit is configured to move between the vicinity of the discharge port and the second paper feed roller. 6. When a print selection signal for selecting double-sided printing or single-sided printing is input from the outside and double-sided printing is selected by the print selection signal, the switching means is switched to the reversing means side. The primary printing is performed on one side of the number of printing sheets designated from the outside, and then the switching means is switched to the side of the second sheet discharging section, which is then reversed by the reversing section and the first sheet discharging section. When the secondary printing is performed on the printing paper received in step S1 and single-sided printing is selected by the print selection signal, the switching means is switched to the side of the second sheet discharge unit, and then the external instruction is given. 2. The double-sided printing apparatus according to claim 1, further comprising control means for performing control so that primary printing is performed on one side of a number of printing sheets. 7. The printing drum can be replaced according to a printing color, and the control unit selects double-sided same-color printing or double-sided different-color printing after a print selection signal for selecting double-sided printing is input. When the print color selection signal is input from the outside and the two-sided color printing is selected by the print color selection signal, only when the print drum is replaced with another print drum having a different print color after the primary printing 7. The double-sided printing device according to claim 6, wherein the control unit controls the secondary printing so as to perform the secondary printing. 8. A printing selection signal for selecting double-sided printing, comprising plate making means for producing a desired original plate and plate discharge means for removing the plate from the printing drum. Is input, a print original selection signal for selecting double-sided original printing or double-sided original printing is input from the outside, and if double-sided original printing is selected by the print original selection signal, the After that, the plate discharge means removes the printing plate from the printing drum, and the control means controls the secondary printing only when the plate making means creates a new printing plate and provides it on the printing drum. The double-sided printing device according to claim 6. 9. The printing drum is replaceable according to a printing color, and has a plate making unit for making a printing plate of a desired original document, and a plate discharging unit for removing the printing plate from the printing drum, In the control means, after a print selection signal for selecting double-sided printing is input, a print color selection signal for selecting double-sided same-color printing or double-sided different-color printing, and a print for selecting double-sided same-side original printing or double-sided different-side original printing An original selection signal is input from the outside, color printing on both sides is selected by the printing color selection signal,
When the two-sided document printing is selected by the printing document selection signal, the printing drum is replaced with another printing drum having a different printing color after the primary printing, and then a new printing plate created by the plate making unit is replaced. 7. The double-sided printing apparatus according to claim 6, wherein a plate is provided on the printing drum, and the control unit controls so as to perform the secondary printing next.