JP2774758B2 - 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 in which a master perforated by a thermal head or the like is wound around a porous cylindrical plate cylinder for printing.

[0002]

2. Description of the Related Art A stencil master is mounted on the outer peripheral surface of a plate cylinder composed of a porous cylindrical support layer and a mesh screen layer, ink is supplied to the inner peripheral surface of the plate cylinder, and a press roller or the like is used. A stencil printing apparatus is known in which the ink supplied to the inner peripheral surface of the plate cylinder is passed through the opening of the support layer, the mesh screen layer, and the stencil master, and the ink is transferred to printing paper for printing. Have been.

In the case of the above-mentioned apparatus, first, an original is set, the original is read by a scanner of a reading apparatus, and a stencil master is perforated by a stencil master having a heating element such as a thermal head in accordance with image information, and the master is mounted on a plate cylinder. Printing is performed by being wound around the outer peripheral surface. In general, a printed material check called a trial print is performed to check whether the position of the printed print image is shifted from the image position of the document. If there is no shift in the print image, printing is performed as it is, and if there is a shift in the print image, the vertical and horizontal image positions are adjusted. The cause of the deviation of the printed image is caused by a document skew in a reading device that reads a document while transporting the document, a master skew when a master is transferred from a plate making device to a plate cylinder, and the like.

As disclosed in Japanese Patent Application Laid-Open No. Sho 50-66308, the displacement of the printing paper by changing the relative position between the plate cylinder and the paper is described in Japanese Patent Laid-Open Publication No. Sho 50-66308. A method of adjusting the position of the print image is introduced. For horizontal image position adjustment, refer to
As disclosed in Japanese Patent Publication No. 218435, a method of adjusting the image position by moving the printing paper horizontally with a lever or the like for each paper feed tray, or by moving the plate cylinder in the axial direction while the paper position is fixed. A method of adjusting the image position is employed.

In the offset printing apparatus, as shown in FIG. 17, an aluminum plate or a paper plate is used as a master 107, which is wound around a plate cylinder 130 and used. Since the master 107 used is strong and does not adhere to the plate cylinder 130, the master 107 is rotated by a tilt adjustment member or the like that moves the clamp member 106 holding the tip of the master or moves it in an arc shape. Is moved to adjust the deviation of the print image.

[0006]

However, in the above-mentioned conventional method, it is possible to correct a deviation in one of the vertical and horizontal directions. However, the master is made by bending the image on the master due to the original skew described above. In the case where the master is bent and wound around the plate cylinder due to the master skew, there is a problem that the deviation of the print image cannot be corrected. Also,
In the case of the offset printing system, the master is brought into close contact with the plate cylinder with ink, and when applied to a stencil printing machine where the master itself is thin and does not have sufficient strength, it moves to the image portion of the master even if the tip of the master moves. Therefore, there is a problem that it is not possible to deal with a case where an image is bent and a plate is made or a master is bent and wound around a plate cylinder.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a stencil printing apparatus which solves the above-mentioned problems, easily corrects a skew occurring in a printed image, and obtains a printed image faithful to a document.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a plate cylinder formed by rolling a porous thin plate into a cylindrical shape, and a pair of plate cylinder gears having cylindrical portions fitted to both ends of the plate cylinder. A driving unit for rotating the plate cylinder gear to rotate the plate cylinder, and a phase changing unit for selectively changing the phase of the pair of plate cylinder gears to twist the plate cylinder. Holding means for holding the phase , each of both ends of the thin plate
Of the plate cylinder at least at one point on the cylinder of the plate cylinder gear
Characterized by being supported so as not to slide in the direction .

[0009]

According to the present invention, the image of the master wound around the outer peripheral surface of the plate cylinder is twisted by changing the phase of the pair of plate cylinder gears by the phase changing means so that the image is at a predetermined position. Corrected and moved.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4, reference numeral 3 indicates a plate cylinder. At both ends of the plate cylinder 3, the cylindrical portions 1 of the pair of plate cylinder gears 1 and 2 are provided.
a, 2a are slidably fitted respectively, and the plate cylinder gear 1,
A space is provided between the plate cylinder 2 and both ends of the plate cylinder 3.
The plate cylinder gears 1 and 2 are rotatably supported around a pipe shaft 11 provided with a plurality of small holes for ink supply, and are fastened by stoppers 28 so as not to move in the axial direction.

The plate cylinder 3 has a two-layer structure of a porous cylindrical support layer forming the inner peripheral surface thereof and a mesh screen layer forming the outer peripheral surface thereof. (Only the support layer is shown in the figure.) The plate cylinder 3 is formed by laminating a thin plate made of porous stainless steel or the like and a net made of materials such as synthetic resin fibers or stainless steel fibers in a mesh shape. Its diameter is slightly smaller than the cylindrical portions 1a and 2a of the plate cylinder gears 1 and 2, and is formed by rolling into a cylindrical shape. A round hole 3e into which a stepped screw 5 is slidably fitted is provided at one corner 3z of the plate cylinder 3, and the corner 3z is turned around the screw 5 by the screw 5. 1
a and slidingly stopped. In addition, a slot 32 is provided in another corner 3y, and the corner 3
The y can slide on the cylindrical portion 2a by the stepped screw 33 and is prevented from falling off. The other corners are covered with a stage section 4 of a clamp means to be described later, and the outer peripheral surface thereof is pressed down.

As shown in FIG. 5, pins 30 are planted at the leading end 3c and the rear end 3b of the plate cylinder 3 so that the plate cylinder 3 is not opened. Pulling the leading end 3c and the trailing end 3b of the plate cylinder 3
I 'm stretching .

The clamping means of the master is disposed at a stage 4 provided so as to cover the opening between the front end 3c and the rear end 3b of the plate cylinder 3, and at a position opposed to the stage 4. It is mainly constituted by a clamper 6 which is swingably supported by a clamper shaft 6a. The clamping means is shown only in FIGS.

As shown in FIG. 4, one end 4a of the stage 4 is provided with a round hole 4d into which the above-mentioned screw 5 is slidably inserted. Is attached to the cylindrical portion 1a so as to be rotatable around the screw 5 together with the corner 3z of the above, and is prevented from coming off. The other end 4b of the stage 4 is provided with an elongated hole 31. The other end 4b of the stage 4 slides with the corner 3y of the plate cylinder 3 with the cylinder 3a of the plate cylinder gear 2 by means of a screw 33. It is free and secure. Therefore, the plate cylinder 3 and the stage unit 4 are configured to be displaceable about the screw 5.

The large diameter portions 1b and 2b of the plate cylinder gears 1 and 2 are spur gears, and the first drive gear 10 is attached to the large diameter portion 1b.
The second drive gear 9 meshes with b. The first drive gear 10 is fixed to one end of the drive shaft 8, and the other end of the drive shaft 8 is connected to the spline portion 2 as shown in FIGS.
1 is provided, and a helical first transmission gear 19 is slidably provided on the spline portion 21. The first transmission gear 19 meshes with the helical motor gear 18 of the motor 17, and is slid in the axial direction of the drive shaft 8 by the moving lever 22. Here, the moving lever 22, the first transmission gear 19, and the spline portion 21 constitute the phase changing means 100.

The rotation of the motor 17 causes the motor gear 18, the first transmission gear 19, the drive shaft 8, and the first drive gear 10 to rotate, and the plate cylinder gear 1 is driven to rotate. The second of the helical teeth meshing with the second drive gear 9 and the motor gear 18
The transmission gear 20 is integrally provided in a bobbin shape, and a hole penetrating between both gears is provided, and the above-described drive shaft 8 is inserted into this hole. When the motor 17 rotates, the plate cylinder gear 2 is rotated by the motor gear 18 and the second transmission gear 2.
0, the second drive gear 9 integral with the second transmission gear 20 rotates and is rotationally driven. Here, the motor 17, the motor gear 18, the first transmission gear 19, the second transmission gear 20, the first drive gear 10, and the second drive gear 9 constitute the drive means 200.

By moving the moving lever 22 in the axial direction of the plate cylinder 3, the first transmission gear 19 is slid on the spline portion 21, and the first transmission gear 19 and the motor gear 1 are moved.
8 changes, and the phase between the second transmission gear 20 and the first transmission gear 19 changes. As the phase changes, the phase shift is transmitted to the plate cylinder gears 1 and 2 connected to the second transmission gear 20 and the first transmission gear 19.
Accordingly, the plate cylinder 3 is moved in opposite directions by the screws 5 and the screws 33 fixed to the cylindrical portions 1a and 1b, and is twisted and deformed.

Inside the plate cylinder 3, an ink roller 12 for supplying ink to the inner peripheral surface of the plate cylinder 3, and an ink roller 12 are arranged in parallel with a slight gap. Doctor roller 13 forming pool 14
When the ink pipe for supplying ink to the ink reservoir 14
And the other pipe shaft 11 are arranged. Here, the ink roller 12, the doctor roller 13, and the pipe shaft 11 constitute an ink supply device. A press roller 15 that presses printing paper against the plate cylinder 3 is disposed near the lower portion of the outer peripheral surface of the plate cylinder 3 facing the ink roller 12.

Next, the operation of the stencil printing machine will be described. In FIG. 2, the plate cylinder 3 holds the tip of the master 7 between the clamper 6 of the clamping means and the stage 4. First, one sheet of printing paper is fed to a registration roller (not shown) by a paper supply device (not shown), and is wound around the outer peripheral surface of the plate cylinder 3 at a predetermined timing synchronized with the rotation of the plate cylinder 3 by the registration roller. The printing paper is inserted between the master 7 and the press roller 15. At this time, the ink roller 12 also rotates in the same direction as the rotation direction of the plate cylinder 3. The ink in the ink reservoir 14 is attached to the surface of the ink roller 12 by the rotation of the ink roller 12, and the amount thereof is regulated when passing through the gap between the ink roller 12 and the doctor roller 13, and is supplied to the inner peripheral surface of the plate cylinder 3. Is done. The ink supplied to the inner peripheral surface of the plate cylinder 3 passes through the opening 3d of the plate cylinder 3 by the further rotation of the ink roller 12, and is supplied to the surface of the master 7 which comes into contact with the plate cylinder 3. Then, the press roller 15 separated from the outer peripheral surface of the plate cylinder 3 moves upward,
When the printing paper is pressed against the master 3 wound on the outer peripheral surface of the plate cylinder 3 rotating in the direction of the arrow Y, ink is transferred from the perforated portion of the master 3 to the surface of the printing paper and printed, and the first printing is performed. Test printing is performed by printing the first sheet.

If there is no deviation in the test print image, a predetermined number of prints are sequentially and continuously performed by the same operation as described above.

A case where a deviation occurs in a printed image will be described. When the master 7 is wound obliquely around the plate cylinder 3 as shown by the solid line in FIG.
, The first transmission gear 19 is slid to the left on the spline portion 21 so that the first transmission gear 1
9 by changing the meshing position of the
The phase between the transmission gear 20 and the first transmission gear 19 is changed. The phase shift is transmitted to the plate cylinder gears 1 and 2 connected to the second transmission gear 20 and the first transmission gear 19 by changing the phase. The plate cylinder 3 is twisted in opposite directions by screws 5 and screws 33 fixed to the cylinder portions 1a and 2a, deformed as shown in FIG. 8, and wound around the outer peripheral surface of the plate cylinder 3. The position of 7 is corrected, and the test printing is performed as described above. When the master 7 is wound obliquely with respect to the plate cylinder 3 as shown by a two-dot chain line in FIG. 7, the moving lever 22 is moved to the right to move the position of the master 7 as described above. What is necessary is just to correct as shown in FIG. In addition,
When the phase is set by changing the phase of the plate cylinder gears 1 and 2 by moving the moving lever 22 in the left-right direction to change the phase of the second transmission gear 20 and the first transmission gear 19 as described above. The selectively changed phase is held by a phase holding means provided with a stopper (not shown) for restricting the movement of the moving lever 22 in the left-right direction.

Although the plate cylinder gears 1 and 2 shown in this embodiment are fixed so as not to move in the direction of the pipe shaft 11 by stoppers 28, one of the plate cylinder gears is slidable with respect to the pipe shaft 11. And the slot 3 between the plate cylinder 3 and the stage 4
The plate cylinder 3 and the stage 4 may be slidably mounted on the cylinders 1a and 2a of the plate cylinder gears 1 and 2 with screws by using round holes 1 and 32, respectively. Also, the tip 3 of the plate cylinder 3
As shown in FIG. 10, the plate cylinder 3 may be formed by superimposing the c and the rear end 3b. In this manner, by overlapping the leading end 3c and the trailing end 3b of the plate cylinder 3, it is possible to prevent the ink from scattering from the leading end 3c and the trailing end 3b.
In the above embodiment, the corners 3z, 3y of the plate cylinder 3 are slidably mounted on the cylinders 1a, 2a of the plate cylinder gears 1, 2, respectively, but are not limited to the corners 3z, 3y. Arbitrary peripheral portions at both ends of the plate cylinder 3 may be slidably attached to the cylindrical portions 1a, 2a, respectively.

Further, as shown in FIG. 11, a stepping motor 34 is connected to the moving lever 22 by a lead screw 35.
, And is configured to be movable so that the moving lever 22
May be converted by the number of steps to display the moving amount or set the moving amount.

FIG. 12 shows a modification of the embodiment shown in FIGS. The driving means 201 shown in this embodiment is different from the embodiment shown in FIGS. 1 to 11 in that an electromagnet 36 for selectively integrating the drive shaft 8 and the second transmission gear 20 and a fixed plate 26 made of a magnetic material are used. Only the configuration having The fixed plate 26 is disposed on the spline portion 21 at a position facing the second transmission gear 20 so as to be slidable in the axial direction of the spline portion 21. After the phase of the plate cylinder gears 1 and 2 is changed by the moving lever 22 as described above to set the phase, the electromagnet 36 and the fixed plate 26 attracted to the electromagnet 36 via the second transmission gear 20 form the drive shaft. 8 and the second transmission gear 2
0 and the set phase are held. According to the embodiment shown in FIG. 12, the electromagnet 36 and the second
The set phase is held by integrating the drive shaft 8 and the second transmission gear 20 by the fixed plate 26 attracted via the transmission gear 20, so that the set phase is reliably held without changing again.

FIG. 13 shows another embodiment of the embodiment shown in FIGS. The plate cylinder gear 301 shown in this embodiment,
Numeral 302 designates a cylindrical portion 3 in the embodiment shown in FIGS.
Only the configuration in which grooves 300 for inserting the ends of the plate cylinder 3 in the direction of the pipe shaft 11 are provided in 01a and 302a, respectively. In this embodiment, the plate cylinder 3 is inserted into the groove 300.
Can be prevented from floating or coming off the plate cylinder gears 301 and 302 due to centrifugal force or the like when the plate cylinder 3 rotates. Further, as shown in FIG. 14, a notch 304 is provided at an end of the plate cylinder 3 so that the cylinders 1 a and 1 b of the plate cylinder gears 1 and 2 receive the plate cylinder 3 by the pins 29 so as to be slidable. Is also good.

FIG. 15 shows still another embodiment. The phase changing means 101 shown in this embodiment is different from the embodiment shown in FIGS. 1 to 14 in that the electromagnet 24 is connected to one side of the first transmission gear 19, and the first transmission The only difference is the configuration in which a manual disk 23 made of a magnetic material that changes the phase of the plate cylinder gears 1 and 2 is provided at a position facing the gear 19. The change of the phase of the plate cylinder gears 1 and 2 by the phase changing means 101 first stops the rotation of the motor 17, releases the operation of the electromagnet 24, and disconnects the connection between the first transmission gear 19 and the manual disk 23. The rotation is performed by manually rotating the manual disk 23, rotating the second drive gear 9, and rotating the plate cylinder gear 2. Thereafter, the electromagnet 24 is operated again to activate the first transmission gear 1.
The first transmission gear 19 and the manual disk 23 are connected by attracting the manual disk 23 to the electromagnet 24 via the intermediate member 9 , and both are integrally rotated to rotate the plate cylinder 3 in a predetermined direction. According to this embodiment, since the phase change is performed manually by rotating the manual disk 23, a delicate phase change becomes possible, and a print image can be obtained at a predetermined position. Further, instead of the electromagnet 24, the first transmission gear 19 and the manual disk 23 may be fixed by fixing screws 27 as shown in FIG.

[0027]

As described above, according to the present invention,
Even if the printed image is bent and printed due to skew of the original during plate making, master skew when clamping the master, etc.
By shifting the phase of the pair of plate cylinder gears and twisting the plate cylinder, it is possible to correct the bending generated in the print image and obtain a print image faithful to the original.

[Brief description of the drawings]

FIG. 1 is a perspective view of a stencil printing machine showing one embodiment of the present invention.

FIG. 2 is a sectional view of the stencil printing machine shown in FIG.

FIG. 3 is a plan view of the stencil printing machine shown in FIG.

FIG. 4 is a sectional view of a main part showing a plate cylinder and a stage of the stencil printing machine shown in FIG. 1;

5 is a sectional view of a main part showing a plate cylinder of the stencil printing machine shown in FIG.

FIG. 6 is a sectional view of a main part showing a driving unit and a phase changing unit of the stencil printing machine shown in FIG. 1;

FIG. 7 is a perspective view showing a master obliquely wound around a plate cylinder of the stencil printing machine shown in FIG. 1;

8 is a perspective view in which both ends of the plate cylinder shown in FIG. 7 are twisted to correct the position of a master.

FIG. 9 is a perspective view in which both ends of the plate cylinder shown in FIG. 7 are twisted to correct the position of the master.

FIG. 10 is a perspective view showing another example of the plate cylinder shown in FIG.

11 is a cross-sectional view showing another example of the phase changing means shown in FIG. 6 and a driving means; FIG.

FIG. 12 is a sectional view of a phase changing means and a driving means showing a modified embodiment of the present invention.

FIG. 13 is a cross-sectional view of a plate cylinder gear of a stencil printing machine showing another embodiment of the present invention.

FIG. 14 is a side view of a plate cylinder gear and a plate cylinder showing another example of the plate cylinder gear shown in FIG.

FIG. 15 is a side view of a phase changing unit and a driving unit of a stencil printing apparatus showing still another embodiment of the present invention.

FIG. 16 is a side view of a main part showing another example of the phase changing means shown in FIG. 15;

FIG. 17 is a perspective view illustrating a skew adjustment member of a master in the offset printing apparatus.

[Explanation of symbols]

 1, 2 plate cylinder gear 3 plate cylinder 4 stage 7 master 8 drive shaft 9 second drive gear 10 first drive gear 17 motor 18 motor gear 19 first transmission gear 20 second transmission gear 22 moving lever 200, 201 driving means 100 , 101 Phase changing means

Claims (1)

(57) [Claims] 1. A plate cylinder formed by rolling a porous thin plate into a cylindrical shape, a pair of plate cylinder gears having cylindrical portions fitted to both ends of the plate cylinder, and rotating the plate cylinder gear. Drive means for rotating and driving the plate cylinder, phase changing means for selectively changing the phase of the pair of plate cylinder gears and twisting the plate cylinder, and holding means for holding the selectively changed phase. A stencil printing machine , wherein at least one of both ends of the thin plate is supported by the cylindrical portion of the plate cylinder gear so as not to slide in the rotation direction of the plate cylinder.