JP3318010B2 - Printing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stencil printing machine,
In particular, it relates to a structure in which printing is performed on both sides of one sheet.

[0002]

2. Description of the Related Art Conventionally, a stencil printing apparatus is known as one of the printing apparatuses. In this printing apparatus, a printing base paper corresponding to a plate perforated by a stencil making apparatus is wound on a plate cylinder having an ink passing structure. And a structure in which the ink is transferred from the plate cylinder to the paper closely contacting the base paper by leaching the ink from the inside of the plate cylinder. The plate cylinder is provided with a clamp mechanism for clamping the leading end of the printing base paper for winding the printing base paper, and the clamp mechanism includes a swingable holding claw attached to the surface of the plate cylinder. It is configured.

By the way, in the above-described printing apparatus,
In recent years, it has been desired to reduce the printing cost by reducing the paper consumption.

For this reason, there has been a demand for double-sided printing in which printing is performed on both sides of a sheet. In this double-sided printing, once the printed sheet is removed from the plate cylinder, the back side of the sheet faces the printing base paper on the plate cylinder. This is performed by feeding paper in a state where it is made to be in a state where it is made to be.

[0005] However, in handling such paper, there is a problem that the procedure for re-feeding the paper is troublesome, or that it takes much time to obtain double-sided printing.

Therefore, conventionally, as shown in FIG. 6, a pair of plate cylinders A1 and A2 are provided, and each of the plate cylinders A1 and A2 is wound with a printing base paper having the content to be printed on each side of the sheet. Then, a structure has been proposed in which a sheet fed from a sheet feeding device B is passed between plate cylinders, and printing is performed on both sides of the sheet by pressing the plate cylinders at this time.

[0007]

Generally, clamp mechanisms C1 and C2 are provided on the surface of the plate cylinder for holding the leading edge of the printing base paper. The clamp mechanisms C1 and C2 are provided on the surface of the plate cylinder. Often protruding from. For this reason, the plate cylinder is placed in advance at a position separated by more than the interval including the protruding height of the clamp mechanisms C1 and C2, for example, about 10 mm. No.

Accordingly, in order to bring the plate cylinders into contact with each other from a position apart from each other, it is necessary to move the plate cylinders at a relatively high speed. Of these, the image behind the clamp position may not be printed.

However, when the plate cylinder is brought into contact at a high speed from a distant position as described above, the impact sound generated when the plate cylinder comes into contact with the plate cylinder is generated in an extremely large state. 1
It will occur every rotation.

Further, in order to move a relatively heavy plate cylinder at a high speed and repeat collisions, it is necessary to increase the rigidity of the plate cylinder. Therefore, the plate cylinder and a drive unit for moving the plate cylinder must be rigid. Must be made. Therefore, there has been a problem that the weight of the entire apparatus including the plate cylinder is greatly increased and the cost of the apparatus is significantly increased.

In order to prevent the interference with the clamp mechanism described above, a structure has been proposed in which a concave portion in which the clamp mechanism can be immersed is formed in one of the plate cylinders (for example, Japanese Patent Application Laid-Open No. Hei 3-197078).

However, according to such a proposed structure, not only is it troublesome to form a concave portion in a part of the peripheral surface of the plate cylinder, but also if an ink supply mechanism is provided inside the plate cylinder, In order to prevent interference when the ink supply roller of the supply mechanism approaches the recess, a structure is required to retract the ink supply roller at high speed, and the structure becomes considerably complicated, including measures such as ink leakage in the recess. This cannot be denied, and as a result, the cost of the apparatus may increase.

In a printing apparatus capable of performing such double-sided printing, for example, when performing single-sided printing, it is necessary to prevent ink from being attached to the back side of the surface of the printing paper on which an image is formed. Is required.

For this reason, when performing single-sided printing in a printing apparatus capable of double-sided printing, as described above, unprinted printing paper is fed out to the plate cylinder facing the back side of the printing surface. You must set a non-printable state. Therefore, when single-sided printing is selected, it is necessary to replace the printing base paper wound on the plate cylinder one by one.

If one-sided printing is selected, if the unprinted printing base paper is printed on the plate cylinder on the side corresponding to the printing surface without knowing that it is wound, the printing is performed as it is. A printing error is found after printing, and there is a possibility that printing paper is wasted.

Accordingly, an object of the present invention is to provide a printing apparatus having a structure capable of performing double-sided printing with a simple structure in view of the above-described problems in the conventional printing apparatus.

Another object of the present invention is to provide a method for switching from double-sided printing to single-sided printing.
It is possible to prevent supply of unprinted printing base paper to a non-printing surface and wasteful consumption of printing base paper at the time of this supply, and further, wasteful consumption of printing paper when an incorrect printing surface is selected. It is an object of the present invention to provide a printing apparatus having a structure capable of performing printing.

[0018]

In order to achieve this object, the invention according to claim 1 is provided with an ink supply mechanism inside, and divides a part in the circumferential direction to adjust the leading end of a printing base paper corresponding to a plate. At least one pair of rotatable porous cylindrical plate cylinders each having an overlapping portion capable of coming and going to be sandwiched therebetween are arranged so as to face each other.

The invention according to claim 2 is characterized in that the opposed cylindrical plate cylinders are connected with each other by means of an up-down moving device with their rotary drive units being connected, the up-down moving device being constituted by a gear train. .

The third aspect of the present invention is characterized in that the gear train of the vertical moving device is set such that the number of teeth of adjacent gears is the same or an integer multiple.

According to a fourth aspect of the present invention, one of the divided portions of the overlapping portion is located on the outer diameter line of the cylindrical plate cylinder, and accordingly, the cylindrical plate cylinders are slightly separated from the outer peripheral surface thereof. It is characterized in that it is arranged at a different position.

The invention according to claim 5 is characterized in that the cylindrical plate cylinders are set to continuously press each other while the printing paper is fed.

According to a sixth aspect of the present invention, in the printing apparatus according to any one of the first to fifth aspects, the first and second printing apparatuses are provided.
The first and second plate making devices provided for each of the porous cylindrical plate cylinders, printing surface selecting means for selecting printing on one side or both sides of printing paper, and the printing surface selecting means.
The first porous cylindrical plate is used for printing on the selected one side.
When printing on both sides, first and second porous cylindrical plates
A single-sided / double-sided printing selecting means for selecting a cylinder as a plate cylinder to be used , the printing side selecting means and the single-sided / double-sided printing selecting means are connected to an input side, and the first and the second sides are connected to an output side
A second plate-making apparatus is connected to the control unit, which is capable of setting a feeding state of unprinted printing base paper to one of the first and second porous cylindrical plate cylinders when single-sided printing is selected; Prepared,
When the single-sided printing for only the front side of the printing paper is selected, the control unit does not send the second porous cylindrical plate cylinder to the second printing cylinder.
A warning can be issued if the printing base paper for plate making is not wound.
It is characterized by that.

[0024]

[0025]

[0026]

According to the present invention, by clamping the leading end of the printing base paper in the overlapped portion formed in a part in the circumferential direction, the conventionally used clamping mechanism becomes unnecessary, and this clamping mechanism has been present. As compared with the case, the opposed plate cylinders can be brought closer to each other and brought into contact during printing.

According to the present invention, since the gear train is used for the vertical moving device, the occurrence of a deviation in the vertical position due to elongation or the like, such as when a belt or the like is used, is prevented.

According to the present invention, since unprinted printing base paper can be worn on one of the plate cylinders and the plate cylinders can be pressed together, single-sided printing on printing paper can be performed.

According to the present invention , selection is made when performing single-sided printing.
On the plate cylinder opposite the plate cylinder on the side corresponding to the printed surface
If the printing base paper that has been
Printing by the plate cylinder on the side corresponding to the selected printing surface is performed.
It is. As a result, unprinted printing base paper can be used for plate cylinders that do not require printing.
When the paper is wound, the wasteful procedure of removing the printing paper one by one can be omitted.

Further, according to the present invention, when single-sided printing for only the surface of the printing paper is selected, the unprinted printing base paper is not wound on the second porous cylindrical plate cylinder. Can be warned if the print mode selection is
It is impossible with the printing base paper wound on the plate cylinder at this stage
If you warn that there is something and execute the printing process carelessly
It is possible to avoid waste of printing base paper .

[0031]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

FIG. 1 is a schematic view showing the structure of a main part of the present invention. The feature of this embodiment is that a pair of cylindrical plate cylinders are arranged to face each other with a very small gap. .

That is, in the figure, reference numerals 1 and 10 denote first and second plate cylinders, respectively.
The second plate cylinders 1 and 10 are arranged opposite to each other at a position where the printing paper to be fed can be pressed together. Since the structure of the plate cylinders 1 and 10 is the same, the first plate cylinder 1 will be described below as an example. In addition, regarding the second plate cylinder 10, the first plate cylinder 1
Are indicated by the reference numerals obtained by adding 10 to the reference numerals of the components used in the above.

Although not shown in detail, the first plate cylinder 1 is based on a metal plate having a large number of holes perforated in a range corresponding to a printing base paper winding portion in the circumferential direction and serving as an ink passage portion. On its outer surface, for example, it is composed of a forward / reverse rotatable cylindrical member having an ink-permeable structure in which a screen layer made of, for example, polyester fiber is arranged, and a polymerization portion 1A is provided in a part of the circumferential direction. . This overlapping portion 1A
And the divided wall 1A1 is positioned on the circumference of the first plate cylinder 1 having a regular diameter,
The other divided 1A2 is made longer in circumference than the divided position, has the same diameter as the diameter of the first plate cylinder 1, and is positioned at one end inside 1A1. Therefore, the other divided 1A2 is in a state where the diameter is reduced at a position facing the divided one 1A1, and therefore accumulates the bending force for returning to the normal diameter.
As shown by the two-dot chain line, for example, the other divided 1A1,
By pushing and opening 10A1, a space in which the leading end of the printing base paper can be inserted can be formed. Further, since the divided other 1A2 is given a habit of closely adhering to the inside of the one 1A1 by the flexing force, when the opening is released after the leading end of the printing base paper is inserted, the divided one 1A2 is separated.
The leading end of the printing base paper is sandwiched together with A1 and 10A1.

On the other hand, an ink supply unit 2 is disposed inside the first plate cylinder 1, and the ink supply unit 2 approaches or comes into contact with the inner peripheral surface of the first plate cylinder 1 to make the first plate cylinder 1. And a doctor roller 2B fixed in close proximity to the ink supply roller 2A with a predetermined gap. In the ink supply unit 2, for example, ink discharged from an ink supply pipe 2C provided on a spindle of the first plate cylinder 1 is formed at a position opposed to the ink supply roller 2A and the doctor roller 2B. After being accumulated in a pool and kneaded by these two rollers, the kneaded ink is conveyed to a position where the ink and the first plate cylinder 1 are opposed by the ink supply roller 2A.

In the vicinity of the peripheral surface of the first plate cylinder 1, a first plate making device 3 and a first peeling claw 5 for peeling a sheet are provided.
In the vicinity of the peripheral surface of the second plate cylinder 10, a second plate-making device 13 and a second peeling claw 14 are respectively arranged.

Although not shown in detail, the first and second plate making devices 3 and 13 contain, for example, a roll-shaped printing base paper, and apply a thermal head and a platen roller to the printing base paper to form an original image. Drilled accordingly. Then, the first and second plate making devices 3, 13
The plate making and the non-plate making states are respectively set by signals from the control unit. The control unit will be described later.

Further, the first and second peeling claws 4, 14
Is fixed with its leading end positioned at a position separated by a predetermined gap from the peripheral surface of the first plate cylinder 1. The predetermined gap is an extremely small gap in consideration of the fact that a member corresponding to the clamp mechanism E shown in FIG. 6 does not exist. In FIG. 1, reference numeral 5 denotes a paper discharge tray, and reference numeral 6 denotes a paper feeding device capable of feeding out printing paper. The printing paper fed from the paper feeding device 6 is an image position on a plate cylinder. Is adjusted by the registration roller 6A and fed toward the plate cylinder.

On the other hand, the first and second plate cylinders 1 and 10 are driven to rotate by the structure shown in FIG.

The first and second plate cylinders 1 and 10 described above include:
The first plate cylinder gear 7 and the second plate cylinder gear 17 are respectively integrated with the support shaft supporting this. Of the plate cylinder gears, the second plate cylinder gear meshes with a drive gear 18A fixed to the output shaft of the drive motor 18;
The plate cylinder gear 7 and the second plate cylinder gear 17 are provided with idle gears 19 which mesh with each other. Second plate cylinder 10
The drive gear 18 is provided so as to be able to rotate only without being displaced by a support portion of a printing device (not shown).
A can always mesh with the second plate cylinder gear 17.

The idle gear 19 includes the first and second plate cylinders 1,
The first and second plate cylinder gears 7 and 17 can be rolled around via a first connecting arm 20 and a second connecting arm 21 rotatably mounted by ten spindles, These idle gears 19 can be linked with each other by a connection link 22. Also, of the first and second connecting arms 20 and 21,
One end of a moving rod 23 is attached to the second connecting arm 21 located on the side of the second plate cylinder gear 17, and the idle gear 19 is rotated on the second plate cylinder gear 21 by moving this in the direction of the arrow. It can be moved. Therefore, the gear train including these gears constitutes a planetary gear mechanism, and the number of teeth between each gear is set to be the same as that of an adjacent gear or an integer multiple, as shown in FIG. The number of gear teeth in the gear train is, for example,
9 have the same number of teeth, and the first and second plate cylinder gears 7 and 17 have the same number of teeth.
9 is set to an integral multiple of the number of teeth.

The first and the second by such a planetary gear mechanism.
The rotary drive mechanism for the plate cylinders 1 and 10 constitutes a vertical movement device having a function of adjusting the phase between the first and second plate cylinders. That is, when the moving rod 23 is displaced, the idle gear 19 that meshes with the second plate cylinder gear 21 rolls according to the displacement amount.
Is transmitted to the idle gear 19 meshing with the first plate cylinder gear 6, and the first plate cylinder gear 6 rotates through the rotation of the idle gear 19. Since the phase of the other plate cylinder can be adjusted with respect to the phase of the one plate cylinder, the printing start position can be aligned between the first and second plate cylinders. The rotation transmission between the first and second plate cylinders 1 and 10 having the printing start position set as described above is performed between the idle gears 19 and between the idle gear 19 and the first
Since the meshing with the second plate cylinder gear is set so that the same tooth meshes at the same position, according to the ratio of the number of teeth, for example, if 1: 1, the same tooth always meshes, and
If the ratio is 1: 2 or 1: 3, the same teeth mesh with each other every two or three rotations, and even if the meshing accuracy including the machining accuracy of the gear is poor, the first and second plate cylinders can be meshed with each other. Is obtained in which the relative positional relationship does not change.

The first plate cylinder 1 is different from the second plate cylinder 10 in that
It is provided so as to be able to come and go. For this purpose, the support shaft of the first plate cylinder 1 is attached to the swinging end side of the swingable first plate cylinder arm 24 whose base end is supported by the stationary part of the printing apparatus, and An eccentric cam 25 is disposed in the vicinity of the swinging end of the first plate cylinder arm 24, and a pressure spring 2 having a habit of pulling the second plate cylinder 10 against the eccentric cam 25.
The swinging end of the first plate cylinder arm 24 comes into contact with the urging force of No. 6. The eccentric cam 25 is provided for bringing the first plate cylinder 1 into and out of contact with the second plate cylinder 10 until the leading end of the printing paper is sandwiched between the overlapping portions 1A and 10A of the plate cylinder. Causes the first plate cylinder 1 to move away from the second plate cylinder 10 in a direction away from the second plate cylinder 10, and causes the first plate cylinder 1 to abut on the second plate cylinder 10 when the leading edge of the printing paper is completed. Rotate to displace in the direction.

On the other hand, the above-mentioned control section has the configuration shown in FIG.

That is, the main part of the control unit 27 is constituted by, for example, a microcomputer 27A.
On the input side via the I / O interface 27B, for example, the printing surface selection means 28 of the printing paper, the first plate making device 3, the second plate making device 13, the first plate discharging device 29, the second plate making device, etc.
The plate discharging device 30 and the single-sided / double-sided printing selecting means 31 are connected, and the driving section of the first plate making device 3 is provided on the output side.
The drive unit of the second plate making device, the drive units of the first and second plate discharging devices, the display unit 32, and the motor drive unit 33 are connected to each other. The above-described printing side selection unit 28 and one-sided / two-sided printing selection unit 31 are members for selecting a plate cylinder to be used for printing on one side of printing paper and selecting a printing mode for both sides and a printing mode for one side. And these selections are made by the operator.

The control unit 27 includes a microcomputer 27
A is provided with a ROM 27C and a RAM 27D connected to A. The ROM 27C stores a sequence program of a printing process, and the RAM 27D stores data necessary for the sequence program. RAM
27D, this state is taken in as data when the preprinted printing base paper in the first and second plate making devices 3 and 13 is fed out, and when an unprinted printing base paper is fed out. This state is taken in as data.

Then, the control unit 27 determines the operation state of the first and second plate making devices 3 and 13 by discriminating the one-sided / double-sided printing of the document and the plate cylinder to be used. Has become. Also, for example, the first and second plate-making devices are fed out of the first and second plate making apparatuses for double-sided printing.
When it is determined that single-sided printing is selected while the perforated printing base paper is wound on the plate cylinders 1 and 10 of the plate cylinders 10 and 10, the plate is wound on the plate cylinder corresponding to the surface that does not require printing. The printing base paper is discharged, and a signal for feeding out an unprinted printing base paper from the plate making apparatus is output to the plate cylinder.

Further, the fact that the unprinted printing base paper is wound is stored in the RAM 27D, and when printing is continuously performed under the same conditions as the one-sided printing executed before that, the unprinted printing base paper is unprinted. The plate making device and the plate discharging device provided corresponding to the plate cylinder on which the printing plate of the plate making is wound are not operated, and the unprinted printing plate which has been wound so far is left as it is. To be used. This means that, when a single-sided original is selected, the conditions for continuous one-sided printing are the same as those for the single-sided printing executed before, without rewinding the unprinted printing base paper one by one, that is, If the same plate cylinder is used to wind the unprinted printing base paper, the printing plate is used as it is to reduce the consumption of printing base paper.

In the control section 27, when performing single-sided printing, if the plate cylinder on which the unprinted printing base paper is to be wound is different, the display section 32 warns this state. ing.

In the case of single-sided printing, it is advantageous to print the image on the front side of the printing paper in order to check the printing state. When the user instructs to wind the printing base paper by selecting the plate cylinder side opposite to the image printing, the image is printed on the back surface of the printing paper, and this is obtained as a so-called printing error. Therefore, when the single-sided printing is selected, the control unit 27 instructs the winding of the preprinted printing paper to the printing drum facing the backside of the printing paper. The operation state of the plate making device is switched so that the printing base paper made by the plate making device is fed to the opposed plate cylinder. As a result, in the case of single-sided printing, printing can be performed on the surface of the printing paper, which is the side that is easily viewed.

Next, the operation will be described. FIG. 4 is a flowchart for explaining the procedure of the printing operation executed by the control unit 27. In the flowchart shown in FIG. 4, the first plate cylinder 1 corresponds to the plate cylinder facing the surface of the printing paper at the time of single-sided printing, and the second plate cylinder corresponds to the plate cylinder facing the back side of the printing surface. The case 10 will be described. In the figure, the control unit 27 determines whether or not the printing is double-sided printing based on the presence or absence of a signal from the printing surface selection unit 28 and a signal from the single-sided / double-sided printing selection unit 31 (ST1). In this discrimination, a signal from the printing surface selection means 28 is input when the printing is one-sided printing.
In the case of double-sided printing, the first and second plate cylinders 1, 1
It is determined whether or not the printing base paper as the plate is wound at 0 based on the plate making status from the first and second plate making devices 3 and 13 (ST2). The plate making status of each of the plate making devices 3 and 13 used for this determination is data determined according to whether or not the plate making process has been performed at the current stage in the RAM 27D, and thus is the content determined by this data. When the preprinted printing base paper is wound on the first and second plate cylinders 1 and 10, the printing base paper is discharged (ST3), and the first and second printing cylinders are further processed according to the new image. In the second plate making devices 3 and 13, a perforation process is performed to make a plate, and the printing base paper subjected to the plate making process is fed out (ST4, ST5).

On the other hand, when the eccentric cam 25 is rotated in accordance with the feeding of the printing base paper, the first plate cylinder arm 2 is rotated.
4 is swung in a direction to separate the first plate cylinder 1 from the second plate cylinder 10 (ST6). In this state, the overlapping portion 1 of the first and second plate cylinders 1 and 10 is
A, 10A, which is the other of the divided 1A2, 10A2, is pushed open to form a space for inserting the leading end of the printing paper (ST7). The opening in the overlapping portion is maintained until the leading end of the printing base paper is completely inserted, and whether the insertion of the leading end of the printing base paper is completed is determined by the amount of rotation of the drive motor used for feeding out. Is determined by the information of
(ST8). When the leading end of the printing base paper is completely inserted into the overlapping portions 1A and 10A, the first plate cylinder 1 is moved to the first plate cylinder arm 24 as the eccentric cam 25 returns to the initial position.
Is set to a state where the second plate cylinder 10 can be brought into contact with the second plate cylinder 10, and at this time, the second plate cylinder gear 17 is rotationally driven by the drive motor 18 (ST9). And
When the printing base paper is wound in this manner, the printing paper is fed and discharged in the same manner as in a normal printing operation, and therefore, the operation control of the peeling claws 4 and 14 is executed ( ST10).

If it is determined in step (ST1) that printing is not double-sided printing, it means single-sided printing. In single-sided printing, it is determined whether printing is performed on the front side of printing paper (ST11). ). As described above, this determination is made in response to the fact that printing on the front side of the printing paper is convenient for checking the printing status and the like. Selection of the plate cylinder to be used in accordance with the selection of the print cylinder, that is, using the first plate cylinder 1 facing the front side of the printing paper or the second plate cylinder 1 facing the back side of the printing paper
It is determined according to the selection status of whether to use 0.

When an instruction is given to use a document set for printing on the front side, that is, to use the first plate cylinder 1, in FIG. It is determined whether or not the printing base paper wound on is a non-made plate (ST12). If the printing base paper wound on the second plate cylinder 10 is an unprinted plate, the plate discharging process from the second plate cylinder 10 is stopped (ST13).
This is to save the trouble of winding the unprinted printing base paper once again when the unprinted printing base paper is already wound around the second plate cylinder 10. The printing base paper for plate making is maintained in a wound state until a new printing condition, that is, a state in which the printing base paper for which plate making is completed is wound on the second plate cylinder. Then, in order to perform printing on the surface of the printing paper, a plate discharging process from the first plate cylinder 1 is performed, and a plate making process is performed by a perforation process in the first plate making device 3, and the printing base paper is fed. (ST14 to ST16).

For example, when single-sided printing on the surface of the printing paper is selected and no unprinted printing base paper is wound on the second plate cylinder 10, the display unit 32
Warning message (ST17), warns the operator that the print mode selection is not possible with the printing base paper wound on the plate cylinder at this stage, and executes the printing process carelessly. In this case, the printing base paper is prevented from being wasted.

Further, when printing is not performed on the front side of the printing paper in a state where the one-sided printing is selected, that is, since the printing is performed on the front side, it is erroneously determined that the use of the first plate cylinder 1 should be selected. When the instruction to use the plate cylinder 10 is issued, a warning is displayed that a plate cylinder that does not correspond to the front side printing has been selected, and the first cylinder facing the front side is displayed.
The winding of the prepressed printing base paper on the plate cylinder 1 is set.

That is, in this case, the perforated printing base paper is unwound to the first plate cylinder 1 facing the surface of the printing paper without perforating the selected plate cylinder by the plate making apparatus. Switching of the operation of the device is performed. Therefore, in this case, it is determined whether or not unprinted printing base paper is wound on the first plate cylinder 1. If unprinted printing base paper is wound on the first plate cylinder 1, the unprinted printing base paper is discharged. The printing process is executed by the first plate-making apparatus 3 to feed the printing base paper to the first plate cylinder 1 (ST18 to S18).
T22). In this case, it is assumed that unprinted printing base paper is wound on the second plate cylinder. If no unprinted printing base paper is wound, the printing base paper is discharged. To perform a process of winding unprinted printing base paper.

According to the present embodiment described above, the rotation transmission from the second plate cylinder gear 17 to the first plate cylinder gear 7 does not use a belt or the like that has an elongation change. By making the number of teeth of this gear equal or an integer multiple,
Since the same teeth can always be engaged without any phase shift, it is possible to prevent a shift in the image leading end position between the first and second plate cylinders.

[0059]

As described above, according to the present invention, when printing is performed on both the front and back surfaces of a printing paper with the plate cylinder facing the printing cylinder,
Since the overlapping portion is formed on the peripheral wall of the plate cylinder and used as a clamp mechanism, a member projecting from the surface of the plate cylinder can be eliminated. Therefore, the interval between the plate cylinders facing each other can be made extremely small, thereby making it possible to reduce the moving stroke at the time of pressing and reduce the impact noise.

Further, since the moving stroke can be reduced, it is not necessary to increase the rigidity of the apparatus, and the weight of the apparatus including the plate cylinder can be prevented from increasing.

According to the present invention, when single-sided printing is selected in a state where double-sided printing can be performed, unprinted plate is placed on one plate cylinder, that is, the plate cylinder facing the non-printing surface. Can be wound, and when single-sided printing is selected, if unprinted printing base paper is wound on the plate cylinder facing the non-printing surface at this stage, Since no unprinted printing base paper is wound, wasteful consumption of printing base paper can be prevented.

Further, according to the present invention, the surface of the printing paper
When single-sided printing for only
Unprinted printing base paper is not wound on the porous cylindrical plate cylinder.
Select the print mode
Is not possible with printing base paper wound on the plate cylinder at this stage
If the warning is issued and the printing process is executed carelessly
To avoid waste of printing base paper
Become.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a main configuration of a printing apparatus according to the present invention.

FIG. 2 is a schematic diagram for illustrating a configuration of a drive system used in a main configuration shown in FIG. 1;

FIG. 3 is a block diagram for explaining a configuration of a control unit used in the configuration of the unit shown in FIG. 1;

FIG. 4 is a flowchart for explaining the operation of the control unit shown in FIG. 3;

FIG. 5 is a flowchart for explaining a continuous part of the flowchart shown in FIG. 4;

FIG. 6 is a schematic diagram showing a conventional example around a plate cylinder in a printing apparatus.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 first plate cylinder 1A overlapping portion 1A1 one of divided overlapping portions 1A2 other of divided overlapping portion 3 first plate making device 4 peeling claw 10 second plate cylinder 10A overlapping portion 10A1 of divided overlapping portion On the other hand 10A2 The other of the divided overlapping portions 13 Second plate making device 16 First plate cylinder gear forming a part of the vertical moving device 17 Second plate cylinder gear forming a part of the vertical moving device 18 Drive motor 19 Vertical moving device Idle gear 24 forming a part of the first plate cylinder arm 25 eccentric cam 27 control unit 28 original reading means 29 first plate discharging device 30 second plate discharging device 32 display unit

Claims (6)

(57) [Claims] A first porous cylindrical plate cylinder provided with an ink supply mechanism therein and provided to face each other so that printing on one side or both sides of a printing paper can be selected; and a second porous cylindrical plate cylinder. A rotatable porous cylinder having a porous cylindrical plate cylinder and a polymerization part which can be separated and separated to divide the part in the circumferential direction and hold the leading end of the printing base paper corresponding to the plate A printing apparatus, wherein at least one or more plate cylinders are arranged to face each other. 2. The printing apparatus according to claim 1, wherein the rotation driving portions of the opposed cylindrical plate cylinders are connected by a vertical moving device, and the vertical moving device is constituted by a gear train. 3. The printing apparatus according to claim 2, wherein the gear train of the vertical moving device has the same number of teeth of adjacent gears or a relationship of an integral multiple. 4. The printing apparatus according to claim 1, wherein one of the divided portions of the overlapping portion is located on the outer diameter line of the cylindrical plate cylinder, and the cylindrical plate cylinders are accordingly arranged to be higher than the outer peripheral surface thereof. A printing device that is located slightly away. 5. A printing apparatus according to claim 1, wherein the cylindrical plate cylinders are set to continuously press each other while printing paper is fed. 6. The printing according to claim 1, wherein
A first and a second plate making device provided for each of the first and second porous cylindrical plate cylinders; and a printing surface selecting means for selecting printing on one side or both sides of printing paper. At the time of printing on one side selected by the printing side selecting means.
Uses the first porous cylindrical plate cylinder when printing on both sides.
1, a plate cylinder using a second porous cylindrical plate cylinder,
Single-sided double-sided printing selection means for selecting in said printing surface selecting means and one-sided, double-sided printing selection means is connected to the input side, the first, second plate making device is connected to the output side, single-sided printing And a control unit that can set a feeding state of unprinted printing base paper on one of the first and second porous cylindrical plate cylinders when is selected. When single-sided printing for only the single-sided printing is selected, the second porous cylindrical plate cylinder
A warning can be issued if the printing base paper for plate making is not wound.
A printing device , characterized in that: