JP2983090B2 - Stencil printing machine - 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.

[0002]

2. Description of the Related Art A conventional stencil printing apparatus is common in many parts to the embodiment of the present invention shown in the drawings, and will be described with reference to this drawing. This stencil printing apparatus has a cylindrical porous plate cylinder 7 which is clamped on the outer peripheral surface by a clamper 6 and has a stencil sheet 11 mounted thereon, and which is rotatably held on a machine frame. It has an ink supply means 8 for supplying ink to the ink roller 17 that comes into contact with the ink roller 17, and a printing pressure roller 9 which is provided so as to be able to contact and separate from the outer peripheral surface of the plate cylinder 7. FIG.
The details of the ink supply means 8 are shown, and a doctor roller 18 is provided with a small gap from the ink roller 17, and an ink reservoir 24 is formed between them.
The presence or absence of the 24 ink is detected by an ink amount detection sensor 21. When the absence of the ink is detected, the ink is supplied by an ink supply pipe 19 and replenished from the ink dropping hole 20 to be supplied. The reservoir 24 is formed, and the ink in the ink reservoir 24 is pushed out from the inner peripheral surface to the outer peripheral surface of the plate cylinder 7 by the ink roller 17 through the minute holes.

[0003] When printing is performed by such a stencil printing apparatus, when printing paper 23 is set on the elevating sheet feeder 1 and a print start key on an operation panel (not shown) is pressed, the sheet feeder is turned on. 1 starts rising and printing paper 23
Abuts on the paper feed roller 2 and stops at a predetermined position. Then, the printing paper 23 is fed by the feed roller 2 and separated by the separation roller 3 and the separation pad 4 one by one.
The sheet is conveyed to the feed roller 4. Then, the skew of the printing paper 23 is corrected and the printing paper 23 is conveyed to the plate cylinder 7 in synchronization with the plate cylinder 7, while the ink is pushed out from the inner peripheral surface to the outer peripheral surface of the printing cylinder 23 as described above. This ink oozes through the micropores of the stencil sheet 11 that has been made and is mounted on the outer peripheral surface of the plate cylinder 7. The printing paper 23 is pressed against the outer peripheral surface of the plate cylinder 7 in such a state by the printing pressure roller 9, whereby the image on the stencil sheet 11 is transferred to the printing paper 23. The printing paper 23 transferred in this manner is separated from the plate cylinder 7 by the suction unit 12 and is discharged to the paper discharge tray 13 after being subjected to crimping for improving paper discharge alignment. At this time, the printing pressure roller 9
Pressing is performed only on the printing area of the plate cylinder 7 in synchronization with the printing timing.

In this stencil printing apparatus, a stencil sheet 11 is used.
The plate making unit 14 is provided, and a plate making unit 14 is provided. In the printing process as described above, in a state where the printing paper 23 is set on the paper feed table 1, an operation panel (not shown) When the stencil making start key is depressed, the manuscript is read by the manuscript reading section 16, the image data is transferred to the stencil making unit 14, and an image is perforated on the stencil sheet 11 by a thermal head (not shown). When the stencil sheet 11 is sent out from the stencil making unit 14, the stencil sheet 11 is cut into a predetermined length and mounted on the plate cylinder 7 in the above-described state. When the stencil printing apparatus as described above is used continuously without much time interval, a clear image is transferred from the first and second printing papers 23 from the beginning, but it takes several hours or more. When used at long intervals, it takes time until the ink on the surface of the plate cylinder 7 dries and the ink inside the plate cylinder 7 oozes out on the surface, and only after transferring several printing papers 23. There is a problem that a clear image cannot be obtained, so that not only the printing paper 23 is wasted, but also it takes time to perform additional printing.

[0005]

In order to solve the above-mentioned problems, a pressure roller provided separately from the printing roller is pressed against the plate cylinder via unused stencil paper or printing paper. This is disclosed in Japanese Utility Model Laid-Open No. 1-206049 and Japanese Utility Model Laid-Open No. 1-144464. However, in the former case, when foreign matter such as dust adheres to the surface of the pressure contact roller, there is a problem that the foreign matter adheres to the surface of the stencil sheet and adversely affects the image. There is a problem that a cleaning mechanism for cleaning the surface of the roller must be provided. Also, in the latter case, even if the pressure of the pressure roller is increased, it takes a long time for the ink to seep out onto the surface of the plate cylinder, and a complete image may not be obtained by one rotation. In order to prevent the pressure roller from coming into contact with the printing paper several times in order to avoid any trouble, a paper ejection mechanism, for example, a mechanism that can arbitrarily release the separation claw without synchronizing with the plate cylinder is provided. Therefore, there is a problem that the entire structure becomes complicated and expensive.

Accordingly, an object of the present invention is to solve the above-mentioned problems of the conventional stencil printing apparatus, and to start printing quickly even when printing after a long interruption time, as in the case of continuous use. Clear images can be obtained from the printing paper, so that the printing paper is not wasted, and even if ink or dust adheres to the pressing roller, only the printed stencil sheet becomes dirty. An object of the present invention is to provide an inexpensive stencil printing apparatus which does not require a cleaning mechanism for cleaning.

[0007]

In order to achieve the above object, the present invention is directed to a cylindrical plate cylinder having a stencil sheet mounted on an outer peripheral surface thereof; A stencil printing machine having an ink supply means for supplying ink to an ink roller contacting an inner peripheral surface of the stencil printing press, and a printing pressure roller provided to face an outer peripheral surface of the cylindrical plate cylinder. Before the printed stencil sheet mounted on the stencil is subjected to printing, without a printing paper, a pressing roller that is directly pressed against the printed stencil sheet in place of the printing pressure roller is provided. Is what you do. According to a second aspect of the present invention, in the first aspect of the present invention, the pressing force of the pressing roller against the cylindrical plate cylinder, and the rotation speed and speed of the cylindrical plate cylinder in a state of being pressed against the cylindrical plate cylinder are changed. In the non-operation time, it is controlled by selecting from preset conditions.

[0008]

In the stencil printing apparatus of the present invention as described above, the invention according to claim 1 is characterized in that the printing pressure does not pass through the printing paper before the printed stencil sheet mounted on the cylindrical plate cylinder is discharged. Instead of the roller, the pressure roller directly presses the printed stencil paper and is pressed against the plate cylinder and rotates, during which the ink in the plate cylinder exudes to the stencil sheet, and the use of the stencil is interrupted for a long time, and the surface of the stencil is stopped. Even if the ink is dry, a clear image can be obtained from the first printing paper as in the case of continuous use, since the printing rises quickly. According to a second aspect of the present invention, in the first aspect of the present invention, the pressing force of the pressing roller against the cylindrical plate cylinder, and the rotation speed and speed of the cylindrical plate cylinder in a state of being pressed against the cylindrical plate cylinder are different from those of the printing apparatus. During operation, it is controlled by selecting from preset conditions, so that the pressing force of the pressure roller to the plate cylinder and the plate, which are optimal for various conditions such as the standing time from the end of printing, ambient temperature, etc. The rotation speed and number of rotations of the cylinder can be selected from the set conditions, the image rises quickly even after being left for a long time, a printed matter with a constant image density can be obtained quickly, and the image rise density is kept constant. .

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the embodiment of the present invention shown in FIGS.
The same parts as those in the conventional art are referred to by the same reference numerals, and the description thereof will be omitted. The different parts will be mainly described.

The printing pressure roller 9 is supported at one end of an arm 15 and pivotally supports a pressure roller 10 at the other end of the arm 15. The middle of the arm 15 is connected to the other end of a lever 14 whose one end is pivotally supported by the body. The lever 14 can be moved between a printing pressure position shown by a solid line and a non-printing position shown by a dashed line in FIG. 1 by an appropriate operating mechanism (not shown). The arm 15 can be rotated by 180 degrees about an intermediate pivot point by an appropriate operating mechanism (not shown).

When printing by the stencil printing apparatus as described above is completed, the stencil sheet 11 having been printed is left attached to the plate cylinder 7, and printing is resumed after a long time. , The operator presses a long idle key (not shown). As a result, the lever 14 is displaced, and the arm 15 moves from the printing pressure position to the non-printing position, where the arm 15 is further rotated by 180 degrees, and the printing pressure roller 9 and the pressing roller 1 are moved.
Then, the arm 15 is moved back from the non-printing position to the printing pressure position, and the pressing roller 10 is pressed against the stencil paper 11, and the plate cylinder 7 is moved until the ink oozes from the surface of the stencil paper 11. By rotating the plate cylinder 7, the state of the ink on the surface of the plate cylinder 7 is set to the same state as in the continuous operation. When this occurs, the stencil sheet 11 is discharged, and thereafter, the new stencil sheet 11 is made by the stencil making unit 14, and the stencil sheet 11 is mounted on the plate cylinder 7 for printing, whereby a clear printed matter is obtained from the beginning. Thus, the printing paper 23 is not wasted. At this time, since the pressure roller 10 directly contacts the surface of the printed stencil 11, the surfaces of the pressure roller 10 and the printed stencil 11 are stained with ink, but the former is not used during printing.
Since the latter is already printed, there is no problem in printing. In this case, the pressing roller 10 may be of any size, material, hardness, etc. as long as the ink can ooze out of the surface of the stencil paper 11.

According to the second aspect of the present invention, according to the second aspect of the present invention, an image or the like is clearly obtained by an experiment or the like in advance, by leaving time, an ambient temperature, a pressing force of the pressing roller 10 against the plate cylinder 7, a rotation speed of the plate cylinder 7, and the like. The number of sheets of printing paper 23, the change in image density, and the like up to the point when the printing is completed are stored as data, and the printing cylinder 7 of the pressure roller 10 suitable for the standing time from the end of the preceding printing and the ambient temperature condition is stored.
The pressurizing force, the rotation speed and the number of rotations of the plate cylinder 7 are input to the memory of the printing apparatus. A backup memory, a timer, a temperature sensor, etc. are provided in the printing device to determine the status of the printing device when it is left for a long time. The pressing force of the roller 10 to the plate cylinder 7, the rotation speed and the number of rotations of the plate cylinder 7 can be selected from the set conditions, and the image rises quickly even after being left for a long time, and a printed matter with a constant image density can be obtained quickly. be able to. In this case, if the number of rotations of the plate cylinder 7 when the pressure roller 10 is pressed against the plate cylinder 7 is too small, the ink does not sufficiently ooze out of the surface of the plate cylinder 7 so that the rising of the image is delayed, and conversely, If the number is too large, too much ink will come out of the surface of the plate cylinder 7, and the rising density of the image will be too high, causing show-through on the printing paper 23 and adverse effects such as slow drying. . In this case, the pressing roller 10 may be of any size, material, hardness, etc. as long as the ink can ooze out of the surface of the stencil paper 11.

[0013]

The present invention is as described above. According to the first aspect of the present invention, there is provided a cylindrical plate cylinder having a stencil sheet mounted on an outer peripheral surface thereof, and an ink contacting an inner peripheral surface of the cylindrical plate cylinder. It has an ink supply means for supplying ink to the rollers, and a printing pressure roller provided opposite to the outer peripheral surface of the cylindrical plate cylinder, and a printed stencil sheet mounted on the cylindrical plate cylinder is printed. Before the printing paper, a press roller is provided instead of the printing pressure roller instead of the printing pressure roller, and the press roller is pressed against the plate cylinder and rotates. Even if the ink oozes to the stencil sheet and the ink on the plate cylinder surface is dry for a long period of use and the ink on the plate cylinder surface is dry, the printing starts quickly and a clear image can be obtained from the first printing paper as in continuous use. The printing paper is not wasted, and Be deposited is Yagomi, since only stencil sheet printed soiling, it is not necessary to provide a cleaning mechanism for cleaning the pressure roller, there is an effect that it is inexpensive. And the invention of claim 2 is:
In the invention of claim 1, the pressing force of the pressing roller against the cylindrical plate cylinder, and the rotation speed and speed of the cylindrical plate cylinder in a state of being pressed against the cylindrical plate cylinder are preset when the printing apparatus is not operated. Since it is selected and controlled from the conditions, the image rises quickly even after being left for a long time, it is possible to quickly obtain a printed matter with a constant image density, and keep the image density at the time of the rise constant. This has the effect of preventing show-through on the printing paper and slowing down of drying.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional front view of a part of an embodiment of the present invention.

FIG. 2 is a vertical sectional front view showing details of an ink supply unit according to the first embodiment.

[Explanation of symbols]

 7 Plate cylinder 9 Printing roller 10 Press roller 11 Stencil sheet 23 Printing paper

Claims (2)

(57) [Claims] 1. A cylindrical plate cylinder having an outer peripheral surface on which a stencil sheet is mounted, ink supply means for supplying ink to an ink roller contacting an inner peripheral surface of the cylindrical plate cylinder, and In a stencil printing machine having a printing pressure roller provided to face an outer peripheral surface, the printed stencil sheet mounted on the cylindrical plate cylinder is not subjected to printing paper before the stencil sheet is printed on the stencil sheet. A stencil printing machine, characterized in that a stencil roller is provided in direct contact with the printed stencil sheet instead of the pressure roller. 2. The pressing force of the pressure roller against the cylindrical plate cylinder, and the rotational speed and speed of the cylindrical plate cylinder in a state of being pressed against the cylindrical plate cylinder are determined from conditions set in advance when the printing apparatus is not operated. 2. The stencil printing machine according to claim 1, wherein the stencil printing machine is selected and controlled.