JP2001088419A - Stencil printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stencil printer capable of using a plurality of types of master rolls in one printer. SOLUTION: The stencil printer comprises a housing 10 for selectively mounting a plurality of types of master rolls having different width sizes in response to an edition size, and a plurality of printing drums 27 having profile sizes responsive to width sizes and length sizes of a maximum edition size of various type edition sizes to be mounted and ink supply opening mesh areas 28 responsive to the width sizes of the masters of the various type edition sizes to be selectively installed thereat.

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, and more particularly to a stencil printing machine in which a plurality of types of stencils (masters) can be used by one printing machine.

[0002]

2. Description of the Related Art Conventionally, a stencil printing machine has been developed according to the size of paper to be printed, for example, according to a standard size such as A3 size or B4 size, or A4 size or B5 size. Printing has been performed by using a master roll adapted to the size of the printer and using a dedicated printing machine to which the master roll can be attached.

[0003] However, there is no problem when various dedicated printing presses are provided in accordance with various master rolls. For example, only one A3 size printing press is provided, and a smaller printing press such as B4 is used. If the printing of a size is to be performed by the printing press, the printing of a size smaller than the size of the printing press is possible, but the printing of the B4 size is performed using the A3 size master roll despite the B4 size printing. I had to print. That is, plate making is performed by perforating only a small area of B4 size using a master roll of A3 size, and a large area around the area is wastefully consumed without being used for plate making or printing. I was

Although it seems that there is no problem if a B4 size master roll is used on an A3 size printing press using a B4 size master roll, it is not so simple in practice. For example, the A3 size master roll has a longer axial length (corresponding to the width dimension orthogonal to the master feeding direction) than the B4 size master roll, and the master roll is attached to supply the master by the length of one plate making. A small B4-size master roll cannot be rotatably supported and mounted on the master supply unit (of the A3-size printing press) to be fed.

[0005] Further, even if a B4 size master roll can be rotatably supported and mounted on a master supply section of an A3 size printing machine, a B4 size master is attached to an A3 size printing drum. When stencil printing is performed, the ink supplied from the inside of the printing drum to the drum surface spreads to an area corresponding to an A3-size master, that is, the ink spreads to an area where no master exists. In other words, an A3-size printing press is provided with an A3-size printing drum, and an A3-size printing drum is provided with an ink supply opening mesh in an area corresponding to an A3-size master. . When a master smaller in size than the area where the mesh is formed is pasted, ink circulates in the outer area beyond the master, and extra ink is printed on A3-size printing paper, or the size of the master is reduced. If the matching B4 size printing paper is used, the excess ink is transferred to the press roller that rotates (co-rotates) with the print drum with the printing paper interposed therebetween, thereby contaminating the press roller. Become.

As described above, for example, even if an attempt is made to perform B4 size printing on an A3 size printing machine, the master roll is B4 size.
In reality, it is necessary to use an A3 size which is more expensive than a size. Therefore, the printing cost increases.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional technical problems. Therefore, an object of the present invention is to provide a stencil printing machine in which a plurality of types of master rolls can be used in one printing machine.

[0008]

SUMMARY OF THE INVENTION A stencil printing machine according to the present invention is characterized by having the following arrangement in order to achieve the object. That is, a base paper supply unit to which a plurality of types of master rolls having different widths depending on the size are selectively mounted, and a width and length of a maximum size among various sizes of the master roll to be mounted. A plurality of printing drums each having an outer dimension corresponding to the width dimension, and having an ink supply opening mesh area corresponding to the width dimension of the base paper of various sizes, and being selectively installed. The printing drum that fits the master roll mounted on the supply unit is selectively installed.

A base paper size detecting means for detecting a size of the base paper by detecting a width of the base paper supplied from the base paper supply unit to the printing drum; and a printing drum selectively installed. It is preferable to further comprise a drum size detecting means for detecting the size of the medium.

Further, when the size of the stencil sheet detected by the stencil size detecting means is incompatible with the size of the printing drum detected by the drum size detecting means, an alarm is issued and the plate making operation is forcibly stopped. Is preferred.

[0011]

FIG. 1 shows a schematic configuration of a stencil printing machine. In general, a stencil printing machine is equipped with a master roll wound in a roll form and supplies the stencil drawn out from the master roll to a stencil making section for the purpose of supplying the stencil paper for each stencil making. The heat-sensitive base paper is made into a plate by a thermal head in a plate making section, and is further supplied to a drum unit. The stencil sheet is affixed onto the peripheral surface of the printing drum of the drum unit, and ink supplied from the inner peripheral side of the drum oozes out onto the peripheral surface and further penetrates into the stencil sheet. The printing paper is supplied between the printing drum ready for printing and the press roller facing the printing drum, and is printed and discharged.

FIGS. 2 and 3 show a schematic configuration of a casing for holding a master roll in a stencil printing machine according to the present invention. The housing 10 includes a front wall 11 and a rear wall 1 as shown in FIG.
2. It has a bottom wall 13 and a side wall 14 and is formed in a substantially rectangular box shape without a lid. As shown in FIG. 3, the master roll 15 is inserted into the housing 10 from above, and the base paper 16 is pulled upward from the rear wall 12 side and crosses the upper end of the front wall 11 to the front (right side in the figure). ). The front wall 11 is fixed, and even if the base paper 16 is pulled forward, the master roll 15 stops against the front wall 11.

The rear wall 12 and the bottom wall 13 are formed integrally, and are urged forward by a coil spring 17 below the bottom wall 13. This is because the rear wall 12 presses the master roll against the front wall 11 and stabilizes the attitude of the master roll in the housing even if the roll diameter is reduced due to a decrease in the remaining amount of base paper of the master roll 15 in the housing 10. It is a configuration for.

The back and forth movement of the integrated structure of the rear wall 12 and the bottom wall 13 is performed by moving the slider 19 projecting below the bottom wall 13 with respect to the guide shaft 18 extending rearward from the lower end of the front wall 11. Are guided by fitting.

The side wall 14 is notched at the upper front end, so that when the master roll 15 is taken out, the core 20
You can put your finger inside.

In the master roll 15, a base paper of a predetermined length is wound around a core 20 (58 mm in an actual product) having a constant outer diameter according to a standard.
mm) is also constant. In addition, the length in the axial direction is different for each size, and is adapted to the width of the corresponding size. Then, the side wall 14 of the housing 10 moves so that the distance between the side walls can be changed in the width direction of the master roll 15 (the axial direction of the roll) with respect to the bottom wall 13 as shown by the dashed line in FIG. It is configured to be possible. With this configuration, a small-sized master roll (a roll that is short in the axial direction) can be accommodated and held. That is, if the A3 size master roll can be accommodated when the distance between the side walls is the maximum, for example, when a smaller size master roll such as a B4 size master roll or an A4 size master roll is accommodated, The distance between the side walls can be variably adjusted according to the width dimension of each master roll.

The side wall 14 can be configured to move while being guided by a guide slit 30 formed in the bottom wall 13 as shown in FIG. 4, for example. Both side walls 14,1
4 moves the master roll 1 with respect to the center of the housing 10.
5 is symmetrical in the width direction and is stopped by a stopper (not shown) so as not to spread outward when positioned. Therefore, the center position of the master roll remains constant regardless of the size of the master roll. Reference numeral 31 denotes a lever for releasing the locking by the stopper in order to return the side walls 14, 14 moved inward to the original outer position.

Even if the side walls 14, 14 are fixed, the distance between the side walls can be adjusted according to the master roll having a short axial length by fitting members serving as spacers at both inner ends thereof. is there.

From the master roll in the housing 10 to the base paper 16
Is pulled out at least in the horizontal direction or downward, and at the same time, so that the master roll 15 itself does not come out of the housing 10.
The height position of the bottom wall 13 is given. That is, the height from the upper end of the front wall 11 to the inner surface of the bottom wall 13 is higher than the radius of the new master roll (44 mm in the actual product) and is at least equal to the outer diameter of the core 20 of the master roll. Or lower than that. Further, when the master roll contact surface of the bottom wall 13 is set to the reference height, the base paper drawn out from the master roll 15 first comes into contact with the base paper, and the contact height position of the base paper contact portion that defines the initial portion of the base paper feed path. (Height dimensions from the above standard height)
Is always smaller than the outer diameter of the master roll, which gradually decreases. In this configuration example, as shown in FIG. 5, the base paper 16 pulled out from the master roll 15 is fed to the plate making section 22 having the thermal head 21, and the upper part of the plate making section is hinged at the base to be hinged. It is covered with a cover member 23 that can be opened and closed up and down, and the front end of the cover member 23 is the above-mentioned first base paper contact position. The tip of the cover member 23 may be equal to the outer diameter of the core of the master roll. In this case, the base paper 16 drawn as the final plate from the master roll 15 is drawn in the horizontal direction. In the figure, reference numeral 24 denotes a guide roller 24 provided in the middle of the base paper feeding path, so that the angle of the base paper entering under the cover member 23 when the remaining base paper becomes small becomes larger than a predetermined angle. The occurrence of chatter vibration of the cover member 23 is suppressed.

In the present embodiment, two optical sensors 25 and 26 are provided on the lower surface of the cover member 23 so that the base paper 16 drawn from the master roll 15 faces the feeding path under the cover member 23. ing. The sensors 25 and 26 are arranged as shown in FIG. 6 when viewed from above, and are arranged corresponding to the width of the base paper of A3 size and B4 size. In the drawing, an alternate long and short dash line indicates the width of a B4 size base paper, and an outer solid line indicates the width of an A3 size base paper. Arrows indicate the feeding direction of the base paper 16. 1st placed inside
The optical sensor 25 detects the presence of the base paper positioned on any of the base papers of the A3 size and the B4 size, regardless of whether the base paper is fed. A3 size base paper passes below, but B4
Medium size base paper does not pass. Conversely, if a base paper smaller than B4 size is fed, the first and second
Neither of the sensors 25, 26 detects the presence of the base paper. The detection level when the presence of the base paper is sensed is H, and the detection level when the presence of the base paper is not sensed is L.
, Both the first and second sensors 25, 26
If the detection levels of both are H, it can be determined that the paper is A3 size base paper. When the detection level of the first sensor 25 is H and the detection level of the second sensor 26 is L, it can be determined that the paper is a B4 size base paper. If the detection levels of both the first and second sensors 25 and 26 are L, it can be determined that the paper is A4 size base paper. Similarly, a third sensor for distinguishing between A4 size and B5 size may be provided further inside the first sensor 25.

The first and second optical sensors 25,
26 is provided on the lower surface of the cover member 23 as a portion facing the feed path of the base paper. In addition, for example, a light shielding plate is attached to the side walls 14 and 14 of the housing 10 shown in FIG.
It is also possible to indirectly detect the width dimension of the base paper by shielding the optical sensor from light with a light-shielding plate interlocking with the movement of the recording paper 4 and 14.

FIG. 7 is a perspective view of the printing drum. The printing drum 27 is prepared for each of various sizes to be mounted, and each of them is formed in a substantially cylindrical shape as shown in FIG. Printing drum 27 for each size
Are the diameters according to the perimeter that is compatible with the length of the maximum size among the various sizes to be mounted, and the axial length is also the length according to the width of the maximum size. And dimensions. Therefore, the contact state with the press roller is maintained in the same manner, regardless of the size of the printing drum 27 used.

Each printing drum 27 has an ink supply opening mesh area 28 corresponding to the width of base paper of various sizes. FIG. 8 shows an ink supply opening mesh area 28 formed on each of the outer peripheral surfaces of the print drum 27 by developing the outer peripheral surface of the print drum 27 so as to be superimposed on one developed view. The longitudinal direction in the figure is the circumferential direction of the drum, and each opening mesh area 28 is formed symmetrically with respect to the center line. The region between the innermost lines A-A is an A4-size aperture mesh region, the region between BB lines is a B4-size aperture mesh region, and C-
The area between the lines C is the aperture mesh area for A3 size.

The ink supply opening mesh area 28 is an area opened in a mesh shape so that ink supplied from the inner peripheral side of the printing drum 27 oozes onto the peripheral surface and further penetrates into the base paper. In the circumferential direction of the printing drum 27, the opening mesh area 28 may have the same length in each case. This means that the base paper of any size is used by being similarly wound around the entire circumference of the print drum 27, but the area actually printed is inside the area made for each size.
In a region where the stencil paper is wound but the stencil is not made, the ink only penetrates into the inner peripheral side of the stencil paper and does not seep into the outer surface of the stencil paper. That is, the surface of the printing paper or the press roller is not stained. The length of the opening mesh area 28 in the circumferential direction may be shortened or lengthened in accordance with the size of each sheet. In this case, it is not necessary to change the length, and the process can be simplified.

Various printing drums 2 configured as described above
7 can be attached to one printing press with compatibility. Therefore, even if the size of the printed material to be printed is different, it is not necessary to arrange the printing presses for each size, and if the printing drum 27 suitable for the size of the printed material to be printed is set in the printing press, one printer is set. A printing machine can print a plurality of sizes.

The printing drum 27 is provided with code information 29 indicating which printing format size the printing drum is for, outside the opening mesh area 28 near the base paper retaining portion. A code reading sensor (not shown) is provided at a position facing the code information 29 on the printing press main body side, and constantly monitors which print format size the set printing drum 27 is for. ing. As described above, the size of the master roll fed from the housing 10 is also determined by the optical sensor 2 on the lower surface of the cover member 23.
5 and 26, the printing drum 27
It can always be checked whether or not the size of the master roll matches the size of the master roll. When the detection signals of these sensors detect a mismatch between the size of the print drum 27 and the size of the master roll,
It is preferable that the operation is forcibly stopped by the control device (CPU) and a warning is issued to the user.

[0027]

As described above, the housing 10 on which the master roll 15 is mounted can mount a plurality of types of master rolls having different sizes, and the printing drum 27 can be interchanged for each size to be printed. Can be set to Accordingly, printing of different sizes can be performed by one printing press, and the master roll does not need to take an extra margin in the width dimension, and is economical.

Further, since the ink supply opening mesh areas 28 of each printing drum 27 have the same length in the circumferential direction of the printing drum 27, the manufacturing process of each printing drum is simple.

Since the print size of the master roll and the print drum is monitored by the sensor, it is possible to prevent the possibility of misprinting due to an incorrect combination.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a schematic configuration of a stencil printing machine.

FIG. 2 is a perspective view showing a schematic configuration of a housing for holding a master roll in the stencil printing machine according to the present invention.

FIG. 3 is a perspective view showing a state where a master roll is mounted on the housing of FIG. 2;

FIG. 4 is a plan view illustrating an example of a side wall moving mechanism in the housing of FIG. 2;

FIG. 5 is an explanatory diagram showing an arrangement of a sensor for detecting a format size of a base paper in a base paper feed path from a master roll to a plate making unit.

FIG. 6 is an explanatory diagram showing the arrangement of sensors in FIG. 5 as viewed from above.

FIG. 7 is a perspective view of a printing drum.

FIG. 8 is a development view of the outer peripheral surface of the printing drum.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Case 11 Front wall 12 Rear wall 13 Bottom wall 14 Side wall 15 Master roll 16 Base paper 17 Coil spring 18 Guide shaft 19 Slider 20 Core 21 Thermal head 22 Plate-making part 23 Cover member 24 Guide roller 25 First optical sensor 26 Second optical sensor Sensor 27 Printing drum 28 Opening mesh area 29 Code information 30 Guide slit 31 Lock release lever

Claims (3)

[Claims] 1. A base paper supply unit (1) on which a plurality of types of master rolls having different widths according to a size are selectively mounted.
0) and an ink having an outer dimension corresponding to the width and length of the maximum size among the various sizes of the master roll to be mounted, and an ink corresponding to the width of the base paper of the various sizes. A plurality of printing drums (2) each having a supply opening mesh area (28) and being selectively installed.
7), wherein the printing drum (27) adapted to the master roll mounted on the base paper supply section (10) is selectively installed. 2. A paper size detecting means (25, 26) for detecting the width of the paper supplied from the paper supply section (10) to the printing drum (27) to detect the size of the paper. The stencil printing machine according to claim 1, further comprising: a drum size detecting means for detecting a size of the printing drum, which is selectively installed. 3. The base paper size detecting means (25, 26).
3. The stencil printing machine according to claim 2, wherein when the size of the base paper detected by the method is incompatible with the size of the printing drum detected by the drum size detecting means, an alarm is issued and the stencil making operation is forcibly stopped.