JP2905584B2 - Rotary stencil printing machine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a rotary stencil printing machine.

2. Description of the Related Art In a rotary type stencil printing machine, as shown in FIG. 3, a metal support cylinder 2a having an infinite number of holes and a mesh screen layer 2b made of, for example, mesh-like polyester fibers mounted on the outer periphery thereof are generally provided as shown in FIG. The leading end of the perforated stencil paper 1 is gripped by a clamper 3 provided on the plate cylinder 2, and the stencil sheet 1 is provided inside the cylinder 2 over its tail. Support cylinder from ink supply device
Due to the viscosity of the ink supplied to the innumerable holes 2a and leaking to the outer periphery of the screen layer 2b, the ink is adhered to the outer peripheral surface of the plate cylinder 2.

The cylindrical plate cylinder 2 on which the stencil sheet 1 is mounted on the outer peripheral surface is supplied with the ink on the inner peripheral surface by the ink supply device, and is rotated around the shaft 16 by the electric motor.
The printing paper 15 is successively placed between the stencil sheet 1 mounted on the peripheral surface of the printer 1 and the press roller 6 urged toward the outer periphery of the plate cylinder 2 via a press roller arm 11 and a press roller support arm 13 by a spring 12. Is controlled by a cam 7 which rotates integrally with the plate cylinder 2 in synchronization with the rotation of the cylindrical plate cylinder 2, and presses the printing paper 15 against the stencil sheet 1 with the press rollers 6 to convey the stencil sheet 1. Printing is performed by moving the ink to the printing paper 15 through the holes.

As shown in FIG. 3, the lower end of the press roller arm 11 is locked by the stopper 10 except during printing, and is supported by the tip of the press roller support arm 13 fixed to the support shaft of the press roller arm 11, as shown in FIG. The press roller 6 is held at a position separated from the plate cylinder 2. As shown in FIG. 3, the cam 7 has a range corresponding to the non-perforated portion where the stencil sheet 1 is not wound around the plate cylinder protruding from the reference circle, and the portion corresponding to the perforated range matches the reference circle. ing. At the time of printing, a registration roller pair 8 is provided to feed the printing paper 15 at a timing coincident with the leading end of the image portion on the stencil sheet 1 wound around the plate cylinder 2 whose leading end rotates. At the position immediately after the pair of registration rollers 8 in the paper feed path, a feeler 9 for sensing the paper is provided with a stopper.
When the printing paper 15 passes over the paper 15 when it is fed, the paper 15 pushes down the feeler 9 as shown in FIG. 4 and the stopper 10 is turned counterclockwise in the drawing. To release the engagement with the press roller arm 11, and the press roller arm 11 is pulled by the spring 12 while the cam follower 11a at the upper end of the press roller arm faces the reference circular portion of the cam 7 with a slight gap. The press roller 6 presses the printing paper 15 against the stencil 1 on the plate cylinder 2, and the cam follower 11 a projects from the cam 7 at the non-opening portion of the plate cylinder 2. 3, the press roller 6 is displaced away from the plate cylinder as shown in FIG. 3, and when the paper 15 has passed through the feeler 9, the feeler 9 rotates clockwise and the stopper 10 The press roller arm 11 is locked.

When printing is performed, ink is consumed in the perforated portion of the stencil sheet 1, and the ink is supplied from the holes of the support cylinder 2a to the screen layer.
The ink is supplied to the holes of the support cylinder 2a by an ink supply device.

In the example shown in FIG. 3, the ink supply device contacts the inner peripheral surface of the plate cylinder 2 at a position facing the press roller 6, and rotates around its own axis in the direction of the arrow.
A doctor roller 5 provided at a slight gap therefrom and rotating around its own axis in the direction indicated by the arrow in the figure;
A gear train (not shown) for transmitting the rotation of the cylindrical plate cylinder to these rollers 4 and 5 for rotation, and a drum shaft 16 formed as a hollow shaft having a plurality of holes on the lower surface and also serving as an ink supply tube.
It is composed of

The V-shaped groove formed by the ink supply roller 4 and the doctor roller 5 forms an ink reservoir 17, and the ink sucked and discharged from the ink pack by the ink pump is supplied to the ink reservoir 17. .

The ink in the ink pool 17 is entrained by the rotation of the ink supply roller 4 and the doctor roller 5 and is measured when passing through a gap (doctor gap) between the two rollers. Forming an ink film,
The ink is supplied to the inner peripheral surface of the cylindrical plate cylinder 2 by being entrained by the ink supply roller 4.

By the way, in the rotary stencil printing machine having the above configuration, after printing, if left for a long time, the ink contained in the opening portion of the plate cylinder or the mesh screen evaporates,
When new base paper is wound around the plate cylinder again and printed,
In the beginning, the ink is insufficient and the ink gradually fills the opening of the plate cylinder and the mesh screen. Therefore, good prints cannot be obtained unless several to several tens of sheets are passed. Therefore, if printing paper is passed from the beginning, several to several tens of waste papers are generated. Further, there is a method of separately preparing and switching the paper for adjusting the tone in order to prevent the generation of the waste paper, but there is a problem that it is troublesome to replace the paper with the printing paper.

Japanese Patent Publication No. Sho 62-30117 discloses that after printing is completed, used stencils are discharged for confidentiality and non-perforated stencil-free stencils are wound around a plate cylinder to prevent ink evaporation. Although a stencil type stencil printing machine is disclosed, it is impossible to completely seal the ink in the plate cylinder and the mesh screen even by this method, and the ink gradually evaporates and the ink is discharged at the next printing. Insufficiency and the same problems as described above are unavoidable. In addition, there is also a disadvantage that the running cost is high because the plate-free base paper is discarded without being used for printing.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-described drawbacks of a conventional rotary stencil printing machine at the time of starting printing with a new base paper, so that a large number of waste papers are generated or a non-plate-making base paper is not used for printing. It is an object of the present invention to provide a rotary stencil printing apparatus that is useful for reducing running costs without discarding.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a rotary stencil printing apparatus having the above-described configuration, in which a means for suppressing rotation of the press roller when the press roller is pressed against the plate cylinder is provided. When the new base paper is applied, the rotation of the plate cylinder is started while the base paper is mounted on the plate cylinder, the printing paper is fed, and the means for suppressing the rotation of the press roller is operated. Then, the press roller is pressed against the plate cylinder, and after rotating the plate cylinder a predetermined number of times, the base paper so far is peeled off from the plate cylinder and discarded.
The printing apparatus is characterized in that control means is provided for setting a new stencil sheet, releasing the press roller rotation suppressing means, and performing a normal printing process.

Operation With the above configuration, when printing with new base paper loaded, the rotation of the plate cylinder is started before the base paper is replaced, and the printing paper is fed before the base paper is replaced. At the same time, with the press roller rotation suppression means activated,
When the press roller is pressed against the plate cylinder across the printing paper, the frictional force between the press roller and the printing paper is larger than the frictional force between the base paper wound around the plate cylinder and the printing paper. Does not move because the press roller is stopped. When the plate cylinder is rotated a predetermined number of times in this state, the printing paper keeps the stopped state, but with the rotation of the plate cylinder, ink is supplied to the inner surface of the plate cylinder by the ink supply device, and the opening of the plate cylinder is opened. Is filled with ink.

After a predetermined number of rotations, the original paper is peeled off from the plate cylinder and discarded.After the new base paper is applied, the rotation suppressing means of the press roller is released, and the printing is performed by the normal printing process. Since the opening in the cylinder is sufficiently filled, a printed matter better than the test print can be obtained.

Examples Hereinafter, examples of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram showing an embodiment in which the present invention is applied to the rotary stencil printing machine described with reference to FIG. Therefore, members having the same functions as those of the apparatus shown in FIG. 3 are denoted by the same reference numerals, and different points will be described with emphasis.

In the apparatus of this embodiment, a ratchet wheel 20 is integrally fixed to the end of the press roller 6, and a stop claw 21 capable of engaging with the teeth of the ratchet wheel is supported on the press roller support arm 13. The other end of the engagement portion is connected to a plunger of a solenoid 22 fixed to the press roller support arm 13.

Other configurations are the same as those of the conventional apparatus described with reference to FIGS. 3 and 4.

After the power is turned on, when a printing instruction is issued, the plate cylinder is rotated at a low speed by a motor, ink is supplied up to a certain amount by an ink detecting member (not shown), and one sheet of printing paper 15 is registered by a paper feeding device (not shown). 8 The registration roller 8 is driven by a motor, a sector gear or the like, and is fed between the plate cylinder 2 and the press roller 6 at a predetermined timing.

A voltage is applied to the solenoid 22 at the same time as the sheet feeding command, and the solenoid 22 is turned on, and as shown in FIG.
To engage the ratchet wheel. As a result, the press roller 6 cannot rotate in the sheet feeding direction, and the sheet is fed from the registration roller 8 so that the stopper 10 at the lower end of the press roller arm 11 (the third
Is released, and the printing paper 15 is pressed against the plate cylinder 2 on which the press roller 6 rotates.

Since the frictional force between the press roller 6 and the printing paper 15 is larger than the frictional force between the base paper wound on the plate cylinder and the printing paper 15, the printing paper 15 is in contact with the base paper 1 wound on the printing drum. Slip between and never move. As the plate cylinder rotates, ink is supplied to the inner peripheral surface of the plate cylinder by the ink roller 4 and the doctor roller 5, and the ink is filled into the support cylinder opening of the plate cylinder and the mesh screen.

When the ink is sufficiently filled, after the plate cylinder has been rotated a set number of times,
The solenoid 22 is turned off, the engagement between the ratchet wheel 20 and the stopper 21 is released, and the stopped paper is conveyed by the plate cylinder 2 and the press roller 6, peeled off by the paper discharge claw 23, and Is discharged. Further, the original paper 1 is peeled off from the plate cylinder 2 by a plate discharging device (not shown) and discarded. A new perforated original paper is subjected to plate printing by a known means, and the printing is shifted to test printing.

Effects As described above, according to the present invention, even if the sheet is left for a long time after the previous printing, the sheet is continuously conveyed in a short time by pressing the original sheet wound on the rotating plate cylinder without conveying the sheet. In the same way as in the state used for, ink can be filled into the holes of the plate cylinder support cylinder and the mesh screen,
Better printed matter can be obtained than printing with a plate (test printing). Also, only one printing paper is used during the filling of the opening with the ink, which generates a large number of waste papers and is far less than the conventional method of discarding using non-perforated base paper. It is economical. As a result of the experiment, it is possible to obtain a printed material equivalent to continuous use during printing with a plate period of 10 days, a plate cylinder rotation speed of 40 rpm, and 5 presses.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing the configuration near the plate cylinder of a rotary stencil printing machine according to an embodiment of the present invention, FIG. FIG. 4 is a cross-sectional view showing a configuration near the plate cylinder of a rotary stencil printing machine to which the present invention is applied, and FIG. 4 is an explanatory diagram for explaining the operation of a press roller during printing. 1 ... stencil sheet 2 ... plate cylinder 4 ... ink roller 6 ... press roller 7 ... cam 8 ... registration roller 9 ... detection feeler 10 ... stopper 11 ... press roller arm 12 ... spring 13 ... … Press roller support arm 15… Printing paper 20… Rachiette wheel (means for suppressing the rotation of the press roller) 21… Stopper 22… Solenoid

Claims (1)

(57) [Claims] 1. A perforated stencil sheet is wound around an outer periphery of a perforated rigid plate cylinder, and printing paper is pressed by a press roller capable of coming in contact with and separating from the stencil sheet wound on the plate cylinder. In a rotary stencil printing machine for performing printing by transferring ink supplied to the inner peripheral surface of the cylinder through the holes of the plate cylinder and the stencil sheet to the printing paper, printing is performed by pressing the press roller against the plate cylinder. At the same time, a means for suppressing the rotation of the press roller is provided, and when the new base paper is formed, the rotation of the plate cylinder is started while the previous base paper is mounted on the plate cylinder, and the printing paper is fed, and The press roller is pressed against the plate cylinder in a state where the means for suppressing the rotation of the press roller is operated, and after rotating the plate cylinder a predetermined number of times, the base paper thus far is peeled off from the plate cylinder and discarded, and the new base paper is discarded. Plates are released and the rotation suppression means of the press roller is released, Rotary stencil printing apparatus characterized in that a control means for controlling to perform the normal printing process.