JP2640231B2 - Plate cylinder for rotary stencil printing - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary stencil printing plate cylinder, and more particularly to a stencil printing paper cylinder wound around an outer peripheral surface thereof. The present invention relates to a rotary stencil printing plate cylinder that performs stencil printing by contact with a stencil printing plate.

2. Description of the Related Art In general, rotary stencil printing uses a cylindrical plate cylinder around which a stencil sheet is wound and mounted on an outer peripheral surface, and the outer periphery of the stencil sheet wound around and mounted on the outer peripheral surface of the plate cylinder. Printing is performed by pressing the printing paper with a press roller or the like while rotating the plate cylinder on the surface, and bringing the printing paper into contact with the outer surface of the stencil printing paper. At this time, the printing paper is affixed to the outer surface of the stencil printing paper with printing ink, and the printing paper is peeled off from the front edge thereof by the rotation of the plate cylinder by a separation claw having a relatively sharp tip. The paper is ejected. Rotary stencil printing apparatuses that perform this type of stencil printing are disclosed in Japanese Patent Publication No. Sho 58-46428 and Japanese Patent Laid-Open Publication No. Sho 61-250631.

Problems to be Solved by the Invention When the printing ink itself has a strong adhesive strength, or when there are many printed images at the leading edge of the printing paper and the printing ink has an adhesive strength to the stencil sheet of the printing paper due to the printing ink. When the stencil strength is exceeded, the leading edge of the printing paper comes into close contact with the outer surface of the stencil sheet, so that a separation claw is provided between the leading edge of the printing paper and the stencil printing sheet. As a result, the printing paper cannot be smoothly removed from the plate cylinder. Such a phenomenon is generally called a rising phenomenon. When the rising phenomenon occurs, a paper jam occurs, and smooth stencil printing cannot be performed smoothly and repeatedly. The rising phenomenon is more likely to occur in a printing paper having a small weight or a printing paper having a low stiffness such as a new paper.

The present invention has been made in view of the above-described problems, and even when the printing ink has a strong adhesive force, and even when a large number of printed images are present at the leading edge of the printing paper, the printing paper is not separated from the plate cylinder. It is an object of the present invention to provide a rotary stencil printing plate which is improved so as to be surely performed by a separating claw.

Means for Solving the Problems According to the present invention, as described above, a stencil sheet for stencil printing is wound around an outer peripheral surface of the stencil sheet, and the stencil sheet is brought into contact with the outer surface of the stencil sheet for printing. This is achieved by a rotary stencil printing plate cylinder in which the corresponding area of the leading edge of the printing paper is raised as compared to other areas in the rotary stencil printing plate cylinder for printing. Is done.

The rotary stencil printing plate cylinder includes an ink-permeable region and an ink-impermeable region, which are substantially stencil-working portions when viewed in the circumferential direction, and the leading edge of the printing paper corresponds to the ink-permeable region. The area to be formed may be a leading edge of the ink passage area when viewed in the direction of rotation of the drum.

The protuberance of the rotary stencil printing plate cylinder may be provided by an ink-permeable member.

Further, the protuberance of the rotary stencil printing plate cylinder may be constituted by an ink passage restricting member.

Operation and Effect of the Invention At the time of printing, the leading edge of the printing paper, which comes into contact with the outer surface of the stencil printing paper wound around the outer peripheral surface of the plate cylinder at the time of printing, is embossed more than other portions by the protrusion provided on the plate cylinder. As a result, the leading edge of the printing paper is slightly separated from the outer surface of the stencil printing paper, whereby the leading edge of the printing paper and the outer surface of the stencil printing paper are separated from each other. A gap is maintained between the gaps, and the separation claw enters the gap, whereby the printing paper is reliably peeled off from the plate cylinder.

In the case where the bulge is constituted by an ink passage restricting member, the ink supply amount at the leading edge of the printing paper is limited, so that the stencil printing paper with the printing ink of the printing paper at this portion is provided. It is avoided that the adhesive force to the adhesive becomes extremely strong. Therefore, this also ensures that a minute gap is formed between the leading edge of the printing paper and the outer surface of the stencil printing paper, and the separation of the printing paper from the plate cylinder by the separation claw is more reliable. Will be performed.

Embodiments The present invention will be described below in detail with reference to the accompanying drawings.

FIGS. 1 and 2 show one embodiment of a stencil printing apparatus including a rotary stencil printing plate cylinder according to the present invention with respect to the essential parts thereof. In the figure, 10 is a plate cylinder for rotary stencil printing, 12 is a squeegee roller for supplying printing ink to the inner peripheral surface of the plate cylinder 10, 14 is a doctor rod for controlling the ink supply amount, and 16 is a doctor rod. Printing paper P against the outer peripheral surface of the plate cylinder 10
Press roller 18 to press the printing paper P from the plate cylinder 10
Are shown respectively. In the illustrated embodiment, the plate cylinder 10 is rotated in a counterclockwise direction in the figure to perform stencil printing in a rotary manner.

The plate cylinder 10 has a two-layer structure including a metal cylindrical body 20 serving as a base material thereof and a screen layer body 22 wound around the outer peripheral surface of the metal cylindrical body 20.

The metal cylindrical body 20 has a porous structure portion 26 having a large number of small holes 24 for ink passage to form an ink-permeable region which is a substantial stencil printing portion, and a small hole to form an ink-impermeable region. A non-porous portion 28 that is not provided is provided in the circumferential direction.

Incidentally, the small holes 24 of the porous structure portion 26 are drawn large so as to be easily understood in the figure, but have a diameter of 0.5 to 0.0.
The porous structure 24, which is a very small hole of about 1 mm and has many small holes 24, may have a porous structure of about 20 to 60 mesh.

A base paper mounting seat 30 is mounted on the non-porous portion 28 of the metal cylindrical body 20. The base paper mounting seat portion 30 is supported on the base paper mounting seat portion 30 by a permanent magnet plate 32 fixed to the base paper mounting seat portion and a pivot shaft 34 at one end, and is selectively magnetically attracted to the permanent magnet plate 32. A clamp plate 36 is provided. Clamp plate
Numeral 36 indicates that the leading end of the stencil sheet S is clamped and held between the two by magnetically attracted to the permanent magnet plate 32, and the leading end of the stencil sheet S is locked to the plate cylinder 10. It is supposed to.

As shown, the stencil sheet S is wound around the outer peripheral surface of the screen layer body 22 of the plate cylinder 10, and is attached to the outer peripheral surface of the screen layer body 22 due to the viscosity of the printing ink. ing.

The screen layer body 22 is wound and mounted on the outer peripheral surface of the metal cylindrical body 20 over the entire area other than the portion where the base paper mounting seat portion 30 is provided. The screen layer body 22 is a screen layer body of about 100 to 500 mesh, which is formed by coating a woven sheet formed by spinning a synthetic resin fiber such as a fluororesin fiber with a metal such as nickel.

A ridge imparting member 40 is provided at a front edge of the porous structure portion 26 of the plate cylinder 10 as viewed in the plate cylinder rotation direction. Raised member 40
1 is provided on the outer surface of the screen layer body 22 as shown in FIGS. 1 and 2 or between the metal cylindrical body 20 and the screen layer body 22 as shown in FIG. The protruding member raises the front edge portion of the porous structure portion 26 in the plate cylinder rotating direction as compared with other portions. The ridge applying member 40 may be provided along one generatrix of the plate cylinder 10 over the entirety thereof, or may be provided partially on both sides in the width direction corresponding to the separation claws 18. This bump imparting member 40
Of the plate cylinder 10 may be about 0.15 to 0.3 mm.

The bump imparting member 40 is formed of a mesh structure formed of a woven fabric of metal fibers such as silk, synthetic resin fibers, and stainless steel, or an ink-permeable member such as an open-cell elastic body such as a sponge.

The printing paper P is fed between the plate cylinder 10 and the press roller 16 so that its leading edge Pa is just located at a position corresponding to the leading edge when viewed in the plate cylinder rotating direction of the porous structure portion 26. As described above, the paper feed timing is set in advance.

The “leading edge” of the printing paper is a strip-like portion adjacent to the leading end of the printing paper, and extends along the paper thickness (when the band is regarded as a band, the width of the band is equal to the width of the band. Since the ratio of (corresponding dimensions) is not so large, this is a portion exhibiting considerable elasticity against bending such that the band is bent in the longitudinal direction.

Accordingly, the region of the plate cylinder 10 corresponding to the front edge Pa of the printing paper P is raised by the protrusion applying member 40 as compared with other regions.

As a result, at the time of printing, the leading edge Pa of the printing paper P that comes into contact with the outer surface of the stencil printing paper S wound and mounted on the outer peripheral surface of the plate cylinder 10 rises from the other portions due to the bulge, and the printing is performed. The leading edge Pa of the paper P is a stencil sheet S
Slightly away from the outer surface of the As a result, a gap D is maintained between the leading edge Pa of the printing paper P and the outer surface of the stencil sheet S, and the leading end of the separation claw 18 enters the gap, whereby the plate cylinder of the printing paper P is moved. Peeling from 10 will be ensured.

As shown, the leading end of the leading edge Pa of the printing paper P is preferably located slightly closer to the rotation direction advance side of the plate cylinder 10 than the protruding portion formed by the protruding member 40. The edge of the plate cylinder 10 on the rotation direction advance side is preferably formed as a sharp end face as shown in the figure.

The bump imparting member 40 may be constituted by an ink passage restricting member that is finer than the screen layer body 22. In this case, the swelling member 40 produces a squeezing effect that limits the amount of ink passing through the arranging portion. As a result, the ink supply amount at the leading edge of the printing paper P is limited, and the adhesion of the printing paper P to the stencil printing paper S by the printing ink at this portion becomes extremely strong. Therefore, a minute gap is reliably formed between the leading edge Pa of the printing paper P and the stencil sheet S.
Peeling from 10 will be performed more reliably.

In the above, the present invention has been described in detail with reference to specific embodiments, but the present invention is not limited thereto.
It will be apparent to those skilled in the art that various embodiments are possible within the scope of the present invention.

[Brief description of the drawings]

FIG. 1 is a schematic structural view showing an essential part of one embodiment of a rotary stencil printing machine provided with a rotary stencil printing paper according to the present invention, and FIG. 2 is a diagram showing a rotary stencil printing machine according to the present invention shown in FIG. A longitudinal sectional view showing an enlarged main part of a plate cylinder for rotary stencil printing,
FIG. 3 is an enlarged vertical sectional view showing another embodiment of a rotary stencil printing plate cylinder according to the present invention, showing a main portion thereof. 10 …… plate cylinder for rotary stencil printing, 12 …… squeegee roller,
14… Doctor rod, 16… Press roller, 18… Separation claw, 20… Metal cylinder, 22… Screen layer, 24…
Small hole, 26 ... Porous structure part, 28 ... No hole part, 30 ... Base paper mounting seat part, 32 ... Permanent magnet plate, 34 ... Axis, 36 ... Clamp plate,
40 …… Protrusion imparting member

Claims (4)

(57) [Claims] In a rotary stencil printing plate cylinder, a stencil printing paper is wound around an outer peripheral surface thereof, and stencil printing is performed by contacting a printing paper with an outer surface of the stencil printing paper.
A plate cylinder for rotary stencil printing, wherein a region corresponding to the leading edge of the printing paper is raised as compared with other regions. 2. A rotary stencil printing plate cylinder according to claim 1, wherein the plate cylinder is substantially free from an ink-permeable area and an ink-free area when viewed in the circumferential direction. A rotatable stencil printing plate cylinder, wherein a region corresponding to the leading edge of the printing paper is a leading edge as viewed in the direction of rotation of the drum of the ink passing region. 3. The rotary stencil printing plate cylinder according to claim 1 or 2, wherein said ridge is provided by an ink-permeable member. Plate cylinder. 4. The rotary stencil printing plate cylinder according to claim 1 or 2, wherein said ridge is constituted by an ink passage restricting member. Plate cylinder.