JPS61188180A - Stencil duplicator - Google Patents

Abstract

PURPOSE:To enable a rapid rise to be obtained in restarting the titled duplicator even after the duplicator is left unused for a long period of time, by providing a power means for driving in the direction for increasing the contact pressure with which an ink-supplying roller is pressed against the inner peripheral surface of a form cylinder. CONSTITUTION:An inking arrangement 19 comprises side plates 30 at both side end part of a squeegee roller 16, and the side plates movably support an end part of a squeegee roller support lever 32 through a pivotal shaft 31. A rod 42 for increasing the contact pressure is fitted between the side plates 30, and is engaged with a free end of the lever 32. A motor 43 for increasing the contact pressure is fitted to the side plates 30, and an eccentric cam 45 is fitted to an output shaft 44 of the motor 43. The cam 45 is engaged with the rod 42, and is driven to rotate counterclockwise by the motor 43 to push the rod 42 downward, thereby driving the lever 32 counterclockwise.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application □ The present invention relates to a stencil printing device, and more particularly to an ink supply system of a single-cylinder rotary stencil printing device.

Conventional single-cylinder rotary stencil printing apparatuses generally include a cylindrical plate cylinder with a porous structure that rotates around its own central axis, and a stencil printing base paper is wrapped around the outer peripheral surface of the stencil printing apparatus. The outer circumferential surface is arranged in contact with the inner circumferential surface of the cylindrical plate cylinder, and rotates around its own central axis to supply printing ink to the inner circumferential surface of the cylindrical five-plate cylinder. , commonly referred to as a squeegee roller1
A stencil printing apparatus of this kind is shown, for example, in Japanese Patent Application Laid-open No. 55889/1989.

Problems to be Solved by the Invention The above-described stencil printing apparatus is left with stencil printing paper wrapped around the outer circumferential surface of the cylindrical plate cylinder when it is not in use. Although covered by the base paper, the inner peripheral surface of the cylindrical plate cylinder is exposed to the atmosphere, so if it is left indoors for a long time, the cylindrical plate cylinder will become trapped in the pores of its porous structure. The printing ink that comes out will harden, which will make it difficult for the printing ink to pass through the cylindrical plate cylinder, and there is a risk that printing will be impaired when it is reused. When printing ink hardens and the flow of printing ink in the cylindrical plate cylinder deteriorates, the amount of printing ink supplied to the stencil printing paper attached to the outer circumferential surface of the cylindrical plate cylinder decreases, causing the stencil printing paper to deteriorate. The compatibility of the printing ink with the paper becomes poor, and it becomes necessary to perform several trial printings before the 11th printing in order to obtain printed matter with an appropriate density. This phenomenon becomes more pronounced the longer the stencil printing apparatus is left unused.

In view of the above-mentioned problems in conventional stencil printing apparatuses, the present invention provides an improved stencil printing apparatus which quickly resumes normal printing operation when restarted even if it is left unused for a long period of time. The purpose is to provide printing @ placement.

Means for Solving the Problems According to the present invention, a cylindrical plate cylinder having a porous structure and having a stencil printing paper wrapped around its outer peripheral surface and rotating around its central axis. an ink supply roller arranged in contact with the inner circumferential surface of the cylindrical plate cylinder at its outer circumferential surface and rotating around its own central axis to supply printing ink to the inner circumferential surface of the cylindrical plate cylinder. This is achieved by a stencil printing apparatus having a power means for selectively driving the ink supply roller in a direction that increases the contact pressure of the ink supply roller against the inner circumferential surface of the cylindrical plate cylinder. Ru.

Effects and Effects of the Invention According to the configuration as described above, the contact pressure of the ink supply roller against the inner peripheral surface of the cylindrical plate cylinder is selectively increased by the power means, so that the printing contained in the cylindrical plate cylinder is If the pressure applied to the ink increases from the inner peripheral surface of the drum to the outer peripheral surface of the drum, and the cylindrical plate cylinder is rotated while this contact pressure increases, the printing ink on the cylindrical plate cylinder increases. The streets are nice and nice all over. Therefore, even if the printing ink contained in the cylindrical plate cylinder hardens and the printing ink in the cylindrical plate cylinder is difficult to pass through, the contact pressure of the ink supply roller against the inner circumferential surface of the cylindrical plate cylinder is maintained as described above. By increasing the number of prints, this problem can be quickly resolved, and printed matter with appropriate density can be obtained quickly without having to make many test prints.

The effect of increasing the contact pressure of the ink supply roller against the inner circumferential surface of the cylindrical plate cylinder, that is, the contact pressure increasing effect, occurs when the power is turned on when using the stencil printing device, and when printing with new stencil printing paper is started, that is, when printing starts with new stencil printing paper, It would be better if it was done at the time of printing. The contact pressure increasing effect when the power is turned on can be performed in a non-printing state, that is, without paper feeding and without operating the press roller (-).The contact pressure increasing effect at the start of printing can be This may be carried out in a normal paper feeding state, that is, in a state in which the press roller is pressed against the outer peripheral surface of the cylindrical plate cylinder while holding the printing paper in between.The contact pressure increasing effect under this normal paper feeding state The effect of this is so remarkable that normal hole plate printing with proper density can be performed next time by just one trial printing using this printing paper.

Note that the contact pressure increase amount when the stencil printing device is powered on may be different from the contact pressure increase effect during plate placement, and the contact pressure increase Il' during plate placement is equal to It's good that it's small compared to the time.

Further, the driving means for driving the ink supply roller in a direction in which the contact pressure against the inner circumferential surface of the cylindrical plate cylinder increases may be configured such that its driving amount can be variably controlled;
In this case, the contact pressure of the ink supply roller against the inner circumferential surface of the cylindrical plate cylinder is variably set depending on the amount of drive, thereby making it possible to adjust the printing density of ordinary printed matter.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail by way of embodiments with reference to the accompanying drawings.

FIG. 1 shows one example of a stencil printing device according to the present invention 71II.
j4 is shown. The stencil printing apparatus shown in FIG. 1 includes a plate-making device, which includes a cylindrical plate cylinder 2, a press roller 3, a paper feed table 4, a paper feed roller 5, and a paper feed roller 6.
a paper feeder 1f7 including a belt conveyor-type paper ejection rack 8, a paper ejection tray 9, a roll storage unit 10 that rotatably and replaceably accommodates a roll member for stencil printing base paper, and a heat-sensitive A type plate making device 11, a base paper cutter 12, and a document mounting table 1
3 and a document discharge passage 14.

The cylindrical plate cylinder 2 is composed of, for example, a metal cylinder with a porous structure and a laminated body of screen mesh wrapped around the outer peripheral surface of the cylinder, and one end of the stencil printing base paper S is attached to a part of the outer peripheral surface. The electric motor 2 has a clamping means 15 for selectively locking the motor 2, and the stencil printing paper S is wrapped around the outer peripheral surface of the electric motor 2.
0, it is rotated counterclockwise in the figure around its own central axis.

An ink supply device 19 having a squeegee roller 16, a doctor rod 17, and an ink supply pipe 18 is provided in the cylindrical plate cylinder 2, and the ink supply device supplies the ink tube 21 according to the rotation of the cylindrical plate cylinder 2. The printing ink is supplied to the inner peripheral surface of the cylindrical plate cylinder 2.

The plate making device 11 includes a light source box 2 which has a light source device 22 and has a light transmitting plate 23 made of transparent glass attached to the upper opening.
4, a press plate 25 that is fixedly arranged above the light source box 24 and faces the light transmitting plate 23, and a release position where the light transmitting plate 22 is separated from the press plate 25, and a position where the light transmitting plate 22 is in the suppressing plate 2.
A drive unit @ 26 that reciprocates the light source box 24 in the vertical direction as shown in the figure to move it to the darkness from the pressed position pressed by 5.
It has

In the stencil printing apparatus constructed as described above, the stencil printing paper S of the roll R is thermally plated by the plate making device 11, and the stencil printing paper S thus made is cylindrical by the clamping means 15. The winding is attached to the outer peripheral surface of the cylindrical plate cylinder 2 while it is locked to the plate cylinder 2, and the printing paper P is fed one by one from the paper feed table 4 in synchronization with the rotation of the cylindrical plate cylinder 2. It is sent toward the outer circumferential surface of the cylindrical plate cylinder 2 and is moved by the press roller 3 while being pressed against the stencil printing base paper S attached to the outer circumferential surface of the cylindrical plate cylinder 2. A printing stroke is formed on the printing paper P by printing ink,
At this time, the printing paper is discharged onto a paper discharge table 9 by a paper discharge device 8.

If a more detailed explanation of this stencil printing device with a plate-making device is required, please refer to Japanese Patent Application No. 57-207216 and Published Patent Application No. 96983/1983 filed by the same applicant as the present applicant. sea bream.

FIGS. 2 and 3 show an enlarged view of the ink supply device, which is a main part of the stencil printing apparatus according to the present invention.

The ink supply device 19 has side plates 30 at both ends of the squeegee roller 16, and each of the side plates pivotally supports one end of a squeegee roller support lever 32 by a pivot 31. Each of the squeegee roller support levers 32 supports a squeegee roller support shaft 33 at its intermediate portion, and the squeegee roller support shaft 33 supports the squeegee roller 16 rotatably around its own central axis.

The side plate 30 supports a doctor rod 17, and the doctor rod 17 is engaged with a long hole 35 provided in the side plate 30 at projections 34 provided at both ends thereof. Projection 3
A stay rod 36 passes through 4, and one end of the stay rod 36 is screwed to the squeegee roller support shaft 33.

A compression coil spring 37 is provided between the protrusion 34 and the squeegee roller support shaft 33 so as to surround the stay rod 36 . The compression coil spring 37 biases the doctor rod 17 in the direction of separating it from the squeegee roller 16.
The size of the gap 38 for ink metering between the squeegee roller 16 and the doctor rod 17 is determined by adjusting the screwing amount of the stay rod 36 with respect to the squeegee roller support shaft 33.

The squeegee roller 16 contacts the inner circumferential surface of the cylindrical plate cylinder 2 with its outer circumferential surface, and rotates counterclockwise in FIG. 2 around its own central axis in synchronization with the rotation of the cylindrical plate cylinder 2. It is designed to rotate. As the squeegee roller 16 rotates, printing ink A is supplied from the ink supply pipe 18 and is formed in the ink pool between the squeegee roller 16 and the doctor socket 17 through the gap 18. It adheres to the outer peripheral surface of the squeegee roller 1.9 in a layer having a thickness determined by the size of the gap 38, and is sent to the inner peripheral surface of the cylindrical plate cylinder 2.

An eccentric cam 40 for contact pressure adjustment is attached to the side plate 30 by a mounting screw 39. The eccentric cam 40 engages the squeegee roller support lever 32 on its outer peripheral surface and pushes the support lever clockwise in FIG. The pressure is adjusted to an appropriate value under normal printing conditions by adjusting the mounting phase.

The side plate 30 supports a contact pressure increasing rod 42 through a long hole 41. The contact pressure increasing rod 42 is stretched between the side plates 30 and engaged with the free end of the squeegee roller support lever 32. In addition, the side plate 30 has a contact pressure increasing electric motor 43.
An eccentric cam 45 is attached to the output shaft 44 of the electric motor. The eccentric cam 45 engages with the contact pressure increasing rod 42 and is rotationally driven by the electric motor 43 in the counterclockwise direction as viewed in FIG. 3, thereby pushing the contact pressure increasing rod 42 downward. The squeegee roller support lever 32 is driven in the counterclockwise direction as seen in FIG.

Under normal conditions, the position of the squeegee roller support lever 32 is determined by the eccentric cam 40, and the contact pressure of the squeegee roller 16 against the inner peripheral surface of the cylindrical plate cylinder 2 is maintained at a contact pressure suitable for normal printing. In other words, the rotational position of the eccentric cam 45 is set by the contact pressure increasing electric motor 43 so that the contact pressure increasing rod 42 does not apply pressure to the squeegee roller support lever 32. When the contact pressure increases during printing, the eccentric cam 45 is rotated by the electric motor 43 in the counterclockwise direction as seen in FIG. 3, and the contact pressure increasing rod 42 is accordingly pushed downward in the figure. The contact pressure increasing rod 42 drives the squeegee roller support lever 32 in the clockwise direction as viewed in FIG. As a result, the contact pressure of the squeegee roller 16 against the inner circumferential surface of the cylindrical plate cylinder 2 increases in accordance with the amount of rotation of the eccentric cam 45 compared to under the above-mentioned normal state.

The operation of the contact pressure increasing electric motor 43 is controlled by a control system as shown in FIG. 4, for example.

This υIll system has an electric control unit @50 that includes a microcomputer, and this control unit controls all of the plate-making and printing operations in addition to controlling the power supply to the contact pressure increasing machines 111 and 43. I'm supposed to do it till the wolf f! 250 receives information regarding the opening and closing of the power switch 51 from the first print switch 5.
2, information regarding the opening and closing of this from the print start switch 53, information regarding the number of prints □ from the print number setting device 54, and information regarding the number of prints □ from the various switches and 0 sensor 55 for plate making and printing □ operations. According to this information, the electric motor 20 for driving the print, the electric motor 43 for increasing contact pressure, and other various electric motors and actuators 5 for plate making and printing (not shown) are given various information.
The control unit controls the operation of 6.

Regarding the contact pressure increase control, when the power switch 51 is closed and the stencil printing apparatus is powered on, the control device 50 generates a signal and a plate to rotate the contact pressure increase electric l1143 by a predetermined amount in the contact pressure increase direction. Electric motor 2 for torso drive
0 at a predetermined rotational speed or a signal to drive the rotation, □Also, when the first print switch 52 is closed, plate making is performed and a new stencil printing base paper S is transferred to the cylindrical plate cylinder 2.
A signal for rotating the contact pressure increasing electric motor 43 by a predetermined amount in the contact pressure increasing direction after being wound around the outer peripheral surface of 20 by a predetermined number of rotations, and at the same time outputs a control signal number to various electric motors and actuators 56 for printing so that printing is performed on one sheet of printing paper.

Therefore, when the power of the stencil printing device is turned on, the press roller 3
2, the contact pressure of the squeegee roller 16 against the inner peripheral surface of the cylindrical plate cylinder 2 is increased by the operation of the contact pressure increasing electric motor 43. In this state, the cylindrical plate cylinder 2 rotates a predetermined number of times. As a result, the printing ink contained in the cylindrical plate cylinder 2, which has hardened when the stencil printing apparatus is left unused, is discharged onto the outer and inner surfaces of the cylindrical plate cylinder □2, which is currently still in the cylindrical plate cylinder. When the stencil printing paper S for the previous printing, which is attached to the outer peripheral surface of the stencil sheet S, is removed, it adheres to the stencil printing paper S and is removed.

When the first print switch 52 is closed, that is, at the time of plate making and printing, the inner periphery of the cylindrical plate cylinder 2 of the squeegee roller is activated by the electric contact pressure increasing electric Ia 43 when a test print is made on a sheet of printing paper P. The contact pressure against the surface is increased, so that the printing ink is reliably adapted to the new stencil printing paper S by a single trial printing.

As a result, printing at the appropriate density can be started immediately after this without wasting printing paper or time.

Furthermore, when the cylindrical plate cylinder 2 rotates a predetermined number of times when the power is turned on and during first printing, the contact increasing electric motor 143 is driven in the reverse direction, and the contact pressure increasing effect thereby is canceled. The contact pressure against the inner circumferential surface of the plate cylinder 2 is maintained at an appropriate level of 1+fl under normal printing conditions determined by the eccentric cam 40.

As described above, the action of increasing the contact pressure of the squeegee roller 16 against the inner circumferential surface of the cylindrical plate cylinder 2 occurs when the stencil printing apparatus is continuously unused for a predetermined period of time, for example, 10 hours or more.
In addition, the amount of contact pressure increase or the rotation speed of the cylindrical plate cylinder 2 in the contact pressure increase state may be changed depending on the continuous standing time. It may be configured to be controlled.

The power means for increasing the contact pressure of the stencil printing apparatus according to the present invention is not limited to the electric vJIa, but may be a solenoid device, a fluid pressure actuator, or other actuators.

Although the present invention has been described in detail with respect to specific embodiments above, the present invention is not limited thereto, and various embodiments are possible within the scope of the present invention. will be clear to those skilled in the art.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing one embodiment of a stencil printing apparatus according to the present invention, and FIG. 2 is an enlarged front view showing a portion of an ink supply device which is a main part of a stencil printing apparatus according to the present invention. , FIG. 3 is a sectional view taken along line 1--2 in FIG. 2, and FIG. 4 is a block diagram showing a control system of a stencil printing apparatus according to the present invention. 2... Cylindrical plate cylinder, 3... Press roller, 4...
Paper feed tray, 5... Paper feed roller, 6... Paper feed roller,
7... Paper feed device, 8... Paper discharge device, 9... Paper discharge stand, 10... Roll storage section, 11... Plate making device, 12
...Base paper cutter. 13... Document placement table, 14... Document discharge path, 15
... Clamping means, 16 ... Squeegee roller, 1
7...Doctor rod, 18...Ink supply pipe,
19... Ink supply device, 20-... Electric motor, 21.
...Ink duplex, 22...Light source device, 23...
Light transmitting plate, 24... Light source box, 25... Pressing plate, 26... Drive device. 30... Side plate, 31... Pivot, 32...' Squeegee roller support lever, 33... Squeegee roller support shaft. 34... Projection, 35... Elongated hole, 36'-Stage O. 37... Compression coil spring, 38... Gap, 39...
・Mounting screw, 40... Eccentric cam for contact pressure adjustment, 41.
・Long hole. 42... Rondo for contact pressure increase, 43... Electric motor for contact pressure increase, 44... Output shaft, 45... Eccentric cam for contact pressure increase, 50... Control device, 51... Power supply Switch, 52... First print switch, 53...
・Print start switch, 54...print number setting device,
55...Various switches and sensors, 56...Various motors and actuators for plate making and printing

Claims (1)

[Claims] A cylindrical plate cylinder with a porous structure that rotates around its central axis and has a stencil printing paper wrapped around its outer circumferential surface, and a plate cylinder that is arranged with its outer circumferential surface in contact with the inner circumferential surface of the cylindrical plate cylinder. In a stencil printing apparatus having an ink supply roller that rotates around the central axis of the cylindrical plate cylinder and supplies printing ink to the inner peripheral surface of the cylindrical plate cylinder, A stencil printing device that has power means that selectively drives in a direction that increases contact pressure against an inner circumferential surface.