JPH0574475B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <<Field of the Invention>> The present invention relates to a stencil printing device that allows easy adjustment of printing density on printing paper.

<<Prior art and its problems>> Conventionally, in a stencil printing device, the factors that affect printing density include the amount of ink applied to the squeegee roller, the pressing force of the squeegee roller to the plate cylinder, and the pressure of the press roller to the plate cylinder. Examples include pressure contact force.

Among these factors, when adjusting the print density by varying the amount of ink applied to the squeegee roller, it is sufficient to adjust the minute distance between the squeegee roller and the doctor roller, but if the distance is 1/1 100mm
The adjustment itself requires skill, as the units are quite small, and the doctor roller and squeegee roller must be adjusted to have uniform spacing along their respective longitudinal directions. It is extremely difficult to adjust.

In addition, when adjusting the print density by varying the pressure of the squeegee roller against the plate cylinder, the pressure can be varied by adjusting the eccentric cam, etc., but this also takes density unevenness into consideration. The left and right eccentric cams must be adjusted so that the pressing force is applied evenly, which is an extremely difficult task.

Furthermore, when adjusting the printing density by varying the press pressure of the press roller on the plate cylinder, the press pressure can be varied by adjusting the position of the press spring, or by varying the return force of the spring by adjusting the screw. Although it is relatively simple to do this, it must also be adjusted by taking into consideration the parallelism of the press rollers, and it is difficult for the user to adjust it himself.

In addition, when the print density changes due to factors such as temperature changes, there is a problem in that the user cannot adjust the print density himself.

<<Object of the Invention>> An object of the present invention is to provide a stencil printing apparatus configured such that printing density can be easily adjusted only by inputting information from an operation panel.

<<Structure and Effects of the Invention>> In order to achieve the above object, the present invention provides a stencil plate in which printing is performed by pressing a printing paper into contact with a stencil paper wrapped around the outer periphery of a cylindrical plate cylinder using a cylindrical press roller. A printing device; a solenoid device having an actuator that is disposed so as to be able to protrude from one end surface of the case in response to a biasing force corresponding to a voltage applied to a solenoid disposed within a cylindrical case; and the actuator and a connecting member that is connected to the press roller and presses the press roller against the outer periphery of the plate cylinder with a biasing force corresponding to the applied voltage, and sets printing density information to be printed on the printing paper. and voltage control means for controlling the voltage applied to the solenoid device in response to print density information set by the print density setting means; The printing density corresponding to the printing density information is adjusted by the pressing force of the press roller against the plate cylinder obtained by the above-mentioned press roller.

According to this configuration, the pressure control of the press roller with respect to the plate cylinder is performed by the solenoid device, and the applied voltage to be supplied to the solenoid device is controlled according to the print density setting information set by the print density setting means. This makes it possible to adjust the printing density by adjusting the pressing force of the press roller against the plate cylinder simply by operating the operation panel. Printed matter with a desired print density can be obtained by simply operating a print density setting key provided on an operation panel or the like while checking the density status.

≪Explanation of Examples≫ An embodiment of this invention will be described below.

FIG. 1 is an external view of a stencil printing apparatus 1 according to the present invention.

In the figure, a lid 2 is attached to one side of the upper part of a case 1a of a stencil printing device 1 using a hinge 2a (see Figure 3), etc., and the lid 2 can be opened to open and close the lid 2. It is configured to set the stencil paper S at a predetermined position.

Furthermore, in case 1a, as shown in Fig. 2,
An operation panel 5 such as a flat keyboard is provided, and this operation panel 5 includes a numeric keypad 5a for setting the number of prints, a print start key 5b, a print stop key 5c, a print density setting key 5d, a print speed setting key 5e, and a print speed setting key 5e. A display section 5f such as an LCD display for displaying the number of printed sheets and the like is provided.

FIG. 3 shows the internal mechanism of the stencil printing apparatus 1 according to the present invention.

In the figure, a cylindrical plate cylinder 20 is rotatably supported by a machine frame (not shown) around its own central axis 20c. The plate cylinder 20 has a porous structure and has a clamp mechanism 21 on its outer periphery, and the clamp mechanism 21 is configured to intermittently lock one end of the stencil paper S.

That is, the clamp mechanism 21 includes a strip-shaped permanent magnet 22 fixed to the outer peripheral surface of the plate cylinder 20 and extending along one generatrix thereof, and a shaft 23 extending along the axial direction of the plate cylinder 20. Therefore, it has a movable clamp piece 24 which is pivotally supported. In addition, the shaft 23
A gear 25 is attached to one end, and a drive gear 27 supported on one end of a lever 26 is appropriately connected to the gear 25 when the plate cylinder 20 is in the initial rotational position (the position shown in FIG. 3). They are starting to mesh together. The lever 26 is pivotally supported on a machine frame (not shown) by a pivot 28, and when the solenoid 29 is not energized, it is biased counterclockwise in the figure by the spring force of a spring 30, causing the drive gear 27 to rotate. Pull away from 25. On the other hand, solenoid 2
9 is energized, it rotates clockwise in the figure against the spring force of the spring 30, causing the drive gear 27 to mesh with the gear 25 of the plate cylinder 20 at the initial rotation position. There is. The drive gear 27 is rotated appropriately by an electric motor 31 attached to the lever 26, which rotates the gear 25, and the clamp piece 24 is moved between the clamp position where it is attracted to the permanent magnet 22 and the position where it is separated from the permanent magnet 22. On the other hand, it is configured to be rotatably driven between a clamp standby position inclined to form a narrow angle and a fully open position rotated approximately 180 degrees counterclockwise in the figure from the clamp position.

The plate cylinder 20 is drivingly connected to a sprocket 34a provided coaxially with the center axis 20c, and this sprocket 34a is drivingly connected to a drive sprocket 34b of an electric motor 33 by an endless chain 32. With this power transmission device, the plate cylinder 20 is intermittently or continuously rotated clockwise in the figure by the electric motor 33.

Further, a printing ink supply means 35 is provided inside the plate cylinder 20. It has a squeegee roller 36 that is rotatable around a shaft 37, and a doctor rod 38 that extends along the generatrix direction of the roller with a predetermined gap from the outer peripheral surface of the squeegee roller 36. It is configured to supply printing ink from the ink reservoir A to the inner peripheral surface of the plate cylinder 20 by being rotationally driven in the same direction as the plate cylinder 20 in synchronization with the rotation of the plate cylinder 20. That is, as the squeegee roller 36 rotates, the printing ink in the ink pool A passes through the gap between this roller and the doctor rod 38, and at this time, the ink is measured and spread over the outer peripheral surface of the squeegee roller 36 to a uniform thickness. This printing ink layer is applied to the plate cylinder 20 as the squeegee roller 36 rotates.
is supplied to the inner circumferential surface of the printer for printing.

Below the plate cylinder 20, a press solenoid device 400 for pressing the printing paper P against the plate cylinder 20, which is an important part of the present invention, is arranged. This press solenoid device 400, as shown in FIG.
A cylindrical press roller 40 is rotatably attached to one end of a pair of lever elements 50, and a shaft 5 is attached to the other end.
1 is fixed, and both ends of this shaft 51 are connected to the side plate 5.
It is rotatably supported by 2.

Further, a lever 53 is attached to one end of the shaft 51, and a spring 54 is attached to one end of the lever 53, and the spring force of the spring 54 causes the lever element 50 to constantly rotate around the shaft 51 as a fulcrum. It is biased clockwise. An intermediate bar 55 is attached to approximately the center of the lever element 50, and a disc-shaped roller 56 is attached to the lower center surface of the intermediate bar 55.
A support block 58 rotatably supported by a shaft 57 is fixed. This support block 58
A solenoid device 41 having a cylindrical case is disposed below the solenoid device 41, and a solenoid (not shown) is disposed inside the solenoid device 41. It has a cylindrical actuator 59 that is arranged so as to be able to protrude from one end surface of the device 41 . One end of this actuator 59 is attached to the lower surface of an engagement block 60 that engages with the roller 56, and this engagement block 60 is connected to a pipe member 6 with a slit.
1 and is fitted into the screw 6 provided in the tightening block 62 inserted into the outer surface of the pipe member 61.
3, the actuator 59 of the solenoid 41 and the engagement block are connected and fixed. Further, screws 64 are attached to both sides of the engagement block 60.
A rubber-like belt member 65 is attached to this screw 64 and shaft 57.
By spanning the rollers 56 and 60, the engagement between the roller 56 and the engagement block 60 is always maintained even during operation. Further, a coil spring 66 is fitted and fixed in the actuator 59 (see FIG. 3), and a predetermined distance is maintained between the solenoid device 41 and the tightening block 62. This is because the start-up operation of the actuator 59 is slow when the solenoid device 41 is energized, so by keeping it moved upward by a predetermined amount by the spring 66, the influence on the press timing of the press roller 40, etc. is reduced. In addition to preventing the plate cylinder 20
This setting is made in consideration of the amount of movement required to release the press roller 40 so that the clamp mechanism 21 provided on the plate cylinder does not interfere with the press roller 40 during the rotational operation of the plate cylinder.

The paper feed tray 4 is provided with a pinion 48 connected to a motor (not shown) and an output transmission mechanism for transmitting the output of the motor, and a rack 49 engaged with the pinion 48. Rack 49 is
Since it has a wave-like engagement portion 49a that is provided substantially perpendicularly to the paper feed table 4 and is to be engaged with the pinion 48, the paper feed table 4 is also moved up and down as the pinion 48 rotates.
Namely. The paper feed tray 4 is moved up and down in accordance with the amount of printing paper P set on the paper feed tray 4, so that the paper feed mechanism 60 can easily take in the printing paper P.

The paper feeding mechanism 60 includes rollers 61, 6 made of rubber or the like.
2, 63, etc., and takes in printing paper P from the paper feed tray 4 and supplies it to the outer periphery of the plate cylinder 20.

Further, around the plate cylinder 20, a printed paper peeling claw 80 is provided above the paper feed table 4 at a position facing the stencil paper removal mechanism 70 and the paper feeding mechanism 60, and this claw 80 is used to remove the printed paper after printing is completed. This is to remove the printed paper from above the plate cylinder 20, and the peeled paper flies to the lower right side in the figure due to the rotational force given by the rotation of the plate cylinder 20, and is placed on the paper output table 3. Laminated and held in sequence.

On the stencil setting plate 100 for setting the stencil paper S, there is an optical sensor 10 for detecting the presence or absence of the stencil paper S.
1 is provided, and when it is detected that the stencil paper S is set on the stencil paper setting plate 100,
Either one of the feed rollers 102 and 103 is rotationally driven, and the stencil paper S is conveyed to the chrome lamp mechanism 21 via the conveyance path 107.

As explained above, in the printing apparatus 1 in this embodiment, the stencil paper S is conveyed to the clamp mechanism 21, the leading end of which is clamped to a part of the plate cylinder 20, and the stencil paper S is placed on the outer peripheral surface of the plate cylinder 20. After wrapping the stencil paper S and applying ink to the stencil paper S, printing is performed by wrapping and pressing the printing paper P onto the outer peripheral surface of the printing cylinder, and each mechanism is controlled by a microcopy computer.

FIG. 5 shows the electrical components of the stencil printing apparatus 1 according to the present invention.

In the figure, a CPU 200 composed of a microprocessor, etc. has a ROM 21 that stores programs for controlling each mechanism in the device.
0, operation panel 5, optical sensor 101 that detects the presence or absence of stencil paper S, optical sensor 9 that detects that stencil paper S has been conveyed to a position where it can be clamped.
0, a plate cylinder driving motor 3 constituting a plate cylinder driving section for rotating the plate cylinder 20 in divided rotations or continuous rotation;
3. Paper feed roller drive motor 60M, stencil paper S
the motor 102M for driving the conveyance roller that conveys the image, the clamp mechanism 21, the stencil discharge mechanism (stencil removal mechanism) 70, the solenoid device 41, the power supply circuit 230 that controls the applied voltage to be supplied to the solenoid device 41, and the calculation of the microprocessor. Temporarily store the results or use the numeric keypad 5a on the operation panel 5
A RAM 220 is connected to each of the RAMs 220 for storing the number of prints setting information inputted from the printer, printing speed information set using the printing speed setting key 5e, and printing density information set using the printing density setting key 5d. Further, in the figure, 240 is a power source as a power supply source.

Next, the main part of this invention will be explained according to the flowchart shown in FIG.

The stencil paper S (manuscript) is placed on the stencil paper set plate 100.
When set to the top, the optical sensor 101 detects this (Yes at step 501), and the number of prints setting information, print speed setting key 5e, and print density setting key 5 are input using the numeric keypad 5a of the operation panel 5.
When the printing speed and printing density information are input and set using d, each setting information is
It is stored in each area of the RAM 220 (steps 502, 503, and 504), and is one of the conditions for later printing processing.
It becomes one.

Next, when the print start key 5b is pressed (affirmative at step 505), the clamp mechanism 21 is activated based on a command from the CPU 200, and the stencil paper used in the previous printing and wrapped around the plate cylinder 20 is S is released from the clamped state, and then stripped from the outer peripheral surface of the plate cylinder 20 by the plate discharge mechanism 70 and discarded in a plate discharge box (not shown) (step 506).

Next, the conveyance roller drive motor 102M is driven by a command from the CPU 200, whereby the feed roller 102 is rotationally driven, and the stencil paper S is conveyed to the clamp mechanism 21. When the leading edge of the stencil paper S reaches the clamp mechanism 21, the optical sensor 90
This is detected and the detection signal is
When transmitted to the CPU 200, the CPU 200 sends a command to clamp the leading edge of the stencil paper S to the clamp mechanism 21. Therefore, one side edge of the stencil paper S is clamped by the clamp mechanism 21.

Thereafter, in response to a command from the CPU 200, the plate cylinder driving motor 33 is driven to rotate the plate cylinder 20 counterclockwise in the figure, and the stencil paper S is wound around the outer peripheral surface of the plate cylinder 20 (step 507).

In the next step 508, printing processing is performed based on the print number setting information, print speed setting information, and print density setting information stored in the RAM 220. In this printing process, the plate cylinder 20
The plate cylinder drive motor 33 that rotationally drives the
It is controlled based on the printing speed setting information stored in the RAM 220, and the pressing force of the press roller 40 that presses the printing paper P against the plate cylinder 20 according to the printing speed is controlled based on the printing density setting information stored in the RAM 220. controlled based on That is, the CPU 200 controls the power supply circuit 230 based on the print density setting information stored in the RAM 220 to determine the applied voltage to be applied to the solenoid device 41. Therefore, if the printing density is set to a darker direction using the printing density setting key 5d shown in FIG. The pressure force applied to the cylinder 20 increases, and the print density increases.

On the other hand, when the printing density is set toward a lower value, the applied voltage supplied to the solenoid device 41 becomes smaller, and as a result, the pressing force of the press roller 40 against the plate cylinder 20 becomes smaller.

Based on the information stored in the RAM 220 as described above, the plate cylinder 20 and press roller 40 are driven.
The paper feed mechanism 60, squeegee roller 36, etc. are operated to perform printing (step 508).

Next, the CPU 220 determines whether or not the number of printed sheets P of which printing has been completed has reached the set number of print sheets. Here, when the set number of prints is reached (step 509 affirmative), the printing process ends. On the other hand, if the set number of prints has not been reached (No in step 509), the CPU 200 first confirms that the print density has not been changed by operating the print density setting key 5d on the operation panel 5 (step 510).
(No), the next printing process is performed under the previous printing conditions (step 508).

On the other hand, if the print density has been changed (Yes at Step 510), the print density setting information stored in the RAM 220 is changed to the changed print density setting information (Yes at Step 510, Step 511). Therefore, in the subsequent printing process, the press roller 4
0 to the plate cylinder 20, the power supply circuit 2
The applied voltage supplied from the solenoid device 30 to the solenoid device 41 is supplied in accordance with the changed print density setting information. Thereafter, each time the print density is changed by operating the print density setting key 5d, the above process is performed, and the applied voltage to the solenoid device 41 is changed, thereby causing the plate cylinder 20 of the press roller 40 to
The pressure contact force is changed. That is, by changing the pressing force of the press roller 40 against the plate cylinder 20, the printing density on the printing paper P is changed.

[Brief explanation of the drawing]

FIG. 1 is an external view of a stencil printing device according to the present invention, FIG. 2 is an explanatory diagram showing an operation panel, and FIG. 3 is an overall schematic diagram showing the internal mechanism of the stencil printing device,
FIG. 4 is a perspective view showing the press roller, solenoid device, etc. used in the stencil printing device, FIG. 5 is a block diagram showing the electrical components of the stencil printing device, and FIG. 6 is the entirety of the stencil printing device. This is a flowchart showing the operation. 1...Stencil printing device, 5...Operation panel, 5d
...Print density setting key (print density setting means), 2
0... Plate cylinder, 40... Press roller, 41... Solenoid device, 59... Actuator, S...
Duplicate paper.

Claims (1)

[Scope of Claims] 1. A stencil printing device that performs printing by pressing printing paper into contact with stencil paper wrapped around the outer periphery of a cylindrical plate cylinder using a cylindrical press roller; a solenoid device having an actuator configured to protrude from one end surface of the case in response to a biasing force corresponding to a voltage applied to a solenoid provided therein; , a connecting member for pressing the press roller against the outer periphery of the plate cylinder with a biasing force corresponding to the applied voltage, a printing density setting means for setting printing density information to be printed on the printing paper, and the printing density setting means voltage control means for controlling a voltage applied to the solenoid device in response to print density information set by the press roller; A stencil printing apparatus characterized in that a printing density corresponding to the printing density information is adjusted by pressure contact force.