JP3020701B2 - 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 shown in FIG. 3 and includes a cylindrical plate cylinder 1 'on which an outer peripheral surface is wound with a stencil sheet 11, and a cylindrical plate cylinder 1'. A rotatable press roller 8 'supported so as to be able to contact and separate from the stencil sheet 11, and ink supply means 6 for supplying ink to the inner peripheral surface of the cylindrical plate cylinder 1'. Ink is supplied to the inner peripheral surface of the cylindrical plate cylinder 1 ′, and the printing paper is pressed against the stencil paper 11 by the press roller 8 ′, and printing is performed on the printing paper by the ink 16 oozing out from the holes of the stencil paper 11. The outer periphery of the cylindrical plate cylinder 1 'is provided with an opening having a number of small holes from a start point A to an end point B in a counterclockwise direction. Perforations are provided in portions corresponding to the openings. In the figure, reference numeral 2 denotes a screen mesh provided on the outer peripheral surface of the cylindrical plate cylinder 1, and 3 denotes a hollow support shaft 3 also serving as an ink supply pipe. 4 is provided inside the cylindrical plate cylinder 1 and is rotated in the same direction as the cylindrical plate cylinder 1 'by a drive mechanism (not shown) to rotate the ink 16 on its inner peripheral surface. And 5 are doctor rollers disposed with a slight gap between the ink roller 4 and the ink roller 4. These ink rollers constitute ink supply means 6. Reference numeral 7 denotes an outer peripheral surface of the cylindrical plate cylinder 1 '. A clamper for clamping the leading end of the stencil sheet 11 provided in the non-opening portion, a separation claw 9 for separating the printed printing paper from the outer peripheral surface of the cylindrical plate cylinder 1, and a stencil sheet 10 for the cylindrical plate cylinder 1 '. Conveyor rollers for conveying 11 and 12 for cylindrical printing paper A registration roller 13 for feeding the drum 1 'and a paper discharge tray 13 are shown.

In the above case, the press roller 8 'is intermittently pressed against the cylindrical plate cylinder 1' by a press roller vertical cam (not shown) which rotates in synchronization with the cylindrical plate cylinder 1 'during printing. In the standby state, it is held at a position shown in the drawing, which is far away from the cylindrical plate cylinder 1 'so as not to come into contact with the clamper 7. When the press roller 8 'is intermittently pressed against the cylindrical plate cylinder 1', the speed is high, so that the cylindrical plate cylinder 1 '
When the contact is made, a loud impact noise is generated, and the press roller 8 'bounces and vibrates, thereby causing a problem such that density unevenness occurs at the leading end of the image.

[0004]

In order to solve the above-mentioned problem, there has been proposed an apparatus in which a shock absorbing member is provided at an initial pressing position of a plate cylinder at which a press roller starts to contact at the start of printing (see, for example, Japanese Patent Application Laid-Open No. H11-157556). JP-A-3-136890). By the way, in such a printing machine, in order to prevent the printed printing paper from sticking to the surface of the stencil sheet and winding up without being discharged, the printing paper is formed on the outer peripheral surface of the cylindrical plate cylinder. It is preferable that the peeling claw to be peeled off is located as close as possible to the outer peripheral surface of the cylindrical plate cylinder. For that, it is not possible to increase the thickness of the shock absorbing member. There is a problem that a step occurs on the outer peripheral surface of the cylindrical plate cylinder due to the thickness of the shock absorbing member, so that the pressing force by the press roller becomes uneven, thereby causing image unevenness.

Accordingly, an object of the present invention is to solve the above-mentioned problems of the conventional stencil printing apparatus, eliminate the need for providing a clamper, simplify the structure and reduce the cost, and use a cylindrical press roller intermittently. In addition to being not pressed by the plate cylinder, it does not generate a loud impact sound, it also does not bounce and causes uneven density at the image tip, and absorbs shock on the outer peripheral surface of the cylindrical plate cylinder. There is no need to provide members,
An object of the present invention is to provide a stencil printing apparatus in which a step is formed on an outer peripheral surface of a cylindrical plate cylinder and image unevenness is not generated due to uneven pressing force by a press roller.

[0006]

In order to achieve the above object, the present invention is directed to a cylindrical plate cylinder having a stencil paper wound around an outer peripheral surface thereof, A stencil printing machine comprising: a rotatable press roller for pressing a printing sheet against a stencil wrapped around a cylinder; and ink supply means for supplying ink to the inner peripheral surface of the cylindrical plate cylinder. The drum is provided with a number of small holes over the entire outer peripheral surface thereof, and is not provided with a clamper for clamping the stencil sheet. In the position facing the cylindrical plate cylinder, a stencil press roller is provided so as to be able to contact and separate from the stencil sheet, and the stencil sheet is fed toward the cylindrical plate cylinder,
When the leading end of the stencil sheet reaches the position facing the pressing roller, the pressing roller presses the leading end of the stencil sheet, affixes the leading end to the cylindrical plate cylinder, and the stencil sheet is directed toward the cylindrical plate cylinder. The press roller is returned before the perforated portion of the stencil sheet is fed and reaches the press roller. According to a second aspect of the present invention, in the stencil printing apparatus according to the first aspect, the separation distance between the cylindrical plate cylinder and the press roller is significantly reduced. According to a third aspect of the present invention, in the stencil printing machine according to the first aspect, the press roller continues the pressing operation continuously during paper feeding.

[0007]

In the stencil printing apparatus of the present invention as described above, when a start signal is issued, the stencil sheet pierced by the piercing means and is moved to the standby position when the leading end of the stencil sheet conveyed by the conveying roller reaches the pressing roller. A stencil roller is moved to a pressing position to press the stencil sheet against the cylindrical plate cylinder, and at the same time, the cylindrical plate cylinder rotates at the same speed as the stencil sheet feed rate, and the front end portion of the stencil sheet that has not been perforated is moved. The winding is started while being adhered to the cylindrical plate cylinder by the adhesive force of the ink, and immediately before the stencil sheet is conveyed and the perforated portion reaches the press roller, the press roller returns to the standby position, and the cylindrical plate cylinder is returned. Is further rotated, and when the stencil sheet reaches a predetermined length, the stencil sheet is cut by the cutter to complete the winding of the stencil sheet. In this way, when the stencil winding is completed, one sheet of printing paper is conveyed by the paper feeding means and supplied between the press roller and the stencil paper, and the press roller shifts from the standby state to the pressing state. And
The printing paper is pressed against the stencil paper and brought into close contact with it, and at the same time, test printing is performed.The printing paper is peeled from the cylindrical plate cylinder and discharged to the paper output tray.
The press roller is pressed to perform printing in response to the supply of the printing paper, and returns to the standby state by cutting the paper.

[0008]

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 cylindrical plate cylinder 1 is provided with a number of small holes over the entire outer peripheral surface thereof, and is not provided with a clamper. The press roller 8 is spaced apart from the cylindrical plate cylinder 1 at an extremely narrow interval. The pressing roller 14 of the stencil sheet 11 is brought into contact with and separated from the stencil sheet 11 at a position facing the cylindrical plate cylinder 1 on the upstream side of the pressing point of the printing paper 17 by the press roller 8 on the movement path of the stencil sheet 11. The holding roller 14 is rotatably attached to the tip of a support arm 15 pivotally supported at the middle of the body by a shaft 19, and the rear end of the support arm 15 is pivotally supported by a solenoid 18. In such a device, when a start signal is issued, the cylindrical plate cylinder 1 around which the used base paper 11 is wound rotates counterclockwise in the drawing, and is separated and discarded by a plate discharging means (not shown). The plate cylinder 1 stops at a predetermined position. Here the stencil paper 11
Is pierced by a piercing means including a thermal head and a platen roller (not shown),
When it is conveyed by 10 and its tip reaches the pressing roller 14, it is applied to the solenoid 18 and
15 rotates counterclockwise about the shaft 19, and moves the pressing roller 14 from the standby position shown by the dashed line in FIG. 1 to the pressing position shown by the solid line, thereby pressing the stencil sheet 11 against the cylindrical plate cylinder 1. . At the same time, the cylindrical plate cylinder 1 rotates clockwise at the same speed as the feed speed of the stencil sheet 11, and the front end portion of the stencil sheet 11 that has not been perforated is attached to the cylindrical plate cylinder 1 by the adhesive force of the ink. Start winding. Immediately before the stencil sheet 11 is conveyed and the perforated portion reaches the pressing roller 14, the application of the solenoid 18 is released, and the pressing roller 14 returns to the standby position. When the cylindrical plate cylinder 1 further rotates and the stencil sheet 11 reaches a predetermined length, the stencil sheet 11 is cut by a cutter (not shown), and the winding of the stencil sheet 11 is completed.

When the stencil sheet 11 has been wound as described above, one sheet of printing paper 17 is conveyed separately from the other printing sheets by a paper feeding means (not shown), and the timing is adjusted by the registration rollers 12. Press roller 8 and stencil paper 11
The press roller 8 shifts from the standby state shown in FIG. 1 to the pressing state shown in FIG. 2, and presses the printing paper 17 against the stencil sheet 11 to make it close to the stencil sheet 11 and simultaneously performs test printing. Are peeled by the peeling claw 9 and stacked on the paper discharge tray 13. When the paper feed is started, the press roller 8 is pressed to perform printing in response to the supply of the printing paper 17, and returns to the standby state by the paper feed cut.

[0011]

The present invention is as described above. According to the first aspect of the present invention, there is provided a cylindrical printing drum on which a stencil paper is wound on an outer peripheral surface, and a stencil paper wound on the cylindrical printing drum. A stencil printing machine provided with a rotatable press roller for pressing the printing paper and ink supply means for supplying ink to the inner peripheral surface of the cylindrical plate cylinder. No small hole is provided, and no clamper for clamping the stencil sheet is provided, and at a position facing the cylindrical plate cylinder on the upstream side of the press point of the printing paper by the press roller on the movement path of the stencil sheet. The stencil sheet press roller is provided so as to be able to contact and separate from the stencil sheet, and the stencil sheet is fed toward the cylindrical plate cylinder. Press the leading edge of the base paper The front end is attached to a cylindrical plate cylinder, and the stencil sheet is fed toward the cylindrical plate cylinder, and the pressing roller is returned before the perforated portion of the stencil sheet reaches the pressing roller. The stencil paper can be wound around the outer peripheral surface of the cylindrical plate cylinder by the adhesive force of the ink from the leading end of the cylinder, and there is no need to provide a clamper and a clamper opening / closing mechanism. When operating the peeling claw, it is necessary to provide a non-opening of a certain width before and after the clamper in order to make the rise and fall to some extent slow, but it is not necessary to provide such a thing, so it is cylindrical. Small holes are provided on the entire outer peripheral surface of the plate cylinder, so that the diameter can be reduced and the size can be reduced.In addition, the structure can be simplified and provided at low cost. stop This eliminates the need for a special operation to perform the operation, eliminates the impact noise that occurs when the clamper is closed, and eliminates the need for opening and closing the clamper. There is the effect that the time called the first print time until the first sheet is printed can be greatly reduced. According to the second and third aspects of the present invention, in the first aspect of the present invention, the separation distance between the cylindrical plate cylinder and the press roller is significantly reduced, and the press roller continues the pressing operation continuously during paper feeding. The press roller does not intermittently press the cylindrical plate cylinder and does not generate a loud impact sound, and the press roller does not bounce and vibrate to generate uneven density at the image front end. In addition, since no shock absorbing member is provided on the outer peripheral surface of the cylindrical plate cylinder, a step is generated on the outer peripheral surface of the cylindrical plate cylinder, and the unevenness of the pressing force by the press roller does not cause image unevenness. There is.

[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 when the press roller is pressed.

FIG. 3 is a vertical sectional front view of a part of a conventional stencil printing apparatus of the same type as the present invention.

[Explanation of symbols]

 1 plate cylinder 6 ink supply means 8 press roller 10 stencil feed roller 11 stencil paper 14 press roller 15 support arm 16 ink 17 printing paper 18 solenoid

Claims (3)

(57) [Claims] 1. A cylindrical plate cylinder on which a stencil sheet is wound on an outer peripheral surface, a rotatable press roller for pressing a printing sheet against the stencil sheet wound on the cylindrical plate cylinder, and a cylindrical plate cylinder. A stencil printing apparatus provided with ink supply means for supplying ink to an inner peripheral surface of the cylindrical plate cylinder, wherein the cylindrical plate cylinder is provided with a number of small holes over the entire outer peripheral surface thereof, and provided with a clamper for clamping a stencil sheet. The stencil paper pressing roller is provided on the moving path of the stencil paper upstream of the pressing point of the printing paper by the press roller at a position facing the cylindrical plate cylinder so as to be able to contact and separate the stencil paper. When the stencil paper is fed toward the cylindrical plate cylinder and the leading edge of the stencil sheet reaches a position facing the pressing roller, the pressing roller presses the leading end of the stencil sheet and affixes the leading end to the cylindrical plate cylinder. And the stencil sheet is a cylindrical plate. A stencil printing apparatus characterized in that the press roller is returned before the perforated portion of the stencil sheet is fed to the cylinder and reaches the press roller. 2. The stencil printing machine according to claim 1, wherein the distance between the cylindrical plate cylinder and the press roller is significantly reduced. 3. The stencil printing apparatus according to claim 1, wherein the press roller continuously performs a pressing operation during paper feeding.