JPH06134958A - Web stock width regulator - Google Patents

Abstract

PURPOSE:To eliminate a deviation of a previously printed image from a following printed image by providing web stock waviness indexing means for indexing a web stock while substantially waving it in a longitudinal direction at a downstream side of a printer. CONSTITUTION:Web stock waviness indexing means 1 rotatably drives a rotary driver 13 at a peripheral speed of a protrusion of an uneven indexing roller 11 slightly faster than a peripheral speed of blanket cylinders BC, BC of printers P, P'. A web stock W is towed by a towing force generated by a frictional force between the periphery of the roller 11 and the stock W by the drive of the means, the stock W is brought into strong contact with the roller 11 by towing, thereby generating substantially parallel waviness in a longitudinal direction. A longitudinal tension inclined slightly to a centerline side is operated at a downstream side of the printer P, a parallel longitudinal tension is operated at an upstream side, and components of both the tensions are operated at the printer P. The stock W is approached to a central side by the component while feeding, the component is reduced, and both the tensions are operated on the same straight line to be stabilized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for adjusting the width of a web material in a lithographic rotary printing machine for printing on a web material with a plurality of printing units.

[0002]

2. Description of the Related Art In recent years, a lithographic printing press for performing overprinting, for example, multicolor printing of newspapers has been promoted, and it is desired to carry out multipage multicolor printing in a limited installation space. As shown in FIGS. 7 and 8, two sets of the plate cylinder PC and the blanket cylinder BC are arranged, and the respective blanket cylinders BC are arranged on the left and right so that they can be pressure-contacted to each other to form the printing section P. It is open to the public to install four printing units P (for example, INCA-).
FIEJ Research Association
(IFA FJ Research
Association) Issued IFRA News pap
er Techniques English Edi
ION (IFR News Paper Technics English Edition) 1988.
See pages 64 to 73 of APRIL). In this lithographic rotary printing press, the web material paper is made to run substantially vertically, and the blanket cylinders BC, BC pressed against each other, that is, the printing portion, are sequentially passed to perform printing on both surfaces of the web material paper W.

By the way, in lithographic printing, particularly lithographic printing using dampening water, a web material is printed with a line when passing through a printing section and is given water. As the fibers absorb and swell in their diameter, the web stock expands in the width direction. for that reason,
In the overprinting by the planographic rotary printing machine as shown in FIGS. 7 and 8, there is a misalignment between the previously printed printing line and the later printed printing line due to the widthwise expansion of the web material. Has resulted.

Therefore, for example, the devices disclosed in Japanese Patent Laid-Open Nos. 4-73148 and 4-12043 have been proposed. These apparatuses are intended to prevent misalignment of printed lines by applying water to a web material before printing, expanding the web material in the width direction in advance and performing overlapping printing.

[0005]

However, in the apparatus disclosed in the above publication, a sufficient effect cannot be obtained unless a relatively large amount of water is applied to the web material before printing, and only a sufficient effect can be obtained. When water is applied, the web material absorbs water and becomes bulky and becomes heavy.For example, as in newspaper printing, the web material is run to the folding part, and many web materials are stacked and folded, and then cut. In processing, the load when sliding the web material on the turning bar or triangular plate (homer) increases,
The load at the time of cutting and folding at the folding barrel also increases, and further
Even in the shipping process after delivery, some inconveniences associated with increase in bulk and weight occurred.

The present invention has been conceived in view of the above, in which the printed lines printed earlier and the printed lines printed later are used without using water other than water necessary for printing. An object of the present invention is to provide a web material width adjusting device capable of preventing misalignment due to expansion of the web material in the width direction.

[0007]

The present invention achieves the above-mentioned object by providing a corrugated paper traction means for corrugating and pulling a web paper material on the downstream side of a printing unit while waving the web paper material in a direction substantially parallel to its longitudinal direction. Is what you are trying to do.

[0008]

[Operation] From the downstream side of the printing unit P, the web material W
A wavy WA that is substantially parallel to the longitudinal direction is generated on the web material W. Then, as shown in FIG. 5, a tension A in the longitudinal direction inclined toward the center line CL side of the web material W acts on the web material W on the downstream side of the printing portion P, and the web on the upstream side of the printing portion P is acted. A tension B in the longitudinal direction parallel to the center line CL of the web material W acts on the material W. Therefore, in the printing section P, the component C of the tension A and the tension B acts on the web material W.

In this state, when the blanket cylinders BC, BC for nipping the web material W in the printing section P are rotated and the web material W travels, the web material W approaches the center and the component force C is applied.
Disappears, the tension A and the tension B act on the same straight line and become stable, and the web material W passes through the printing section in a state where the both sides of the material are shortened as shown in FIG. To be done. Further, by appropriately adjusting the corrugation WA generated on the web material W, the web material W can be passed through the printing section P in a state where the space between both sides of the paper material is shortened and wrinkle-free.

It is not clear why the web material can pass under the printing pressure of the printing section in a state where both sides of the material sheet are shortened and wrinkle-free. When passing through the pressure reduction, a degree of merging that cannot be visually confirmed is generated in the web material, for example, an aggregation or an increase of fibers constituting the material occurs, and this is pressed by the printing pressure to stabilize the fibers. It is considered that this is due to the action of

By the above-described operation, the widthwise expansion of the web material which occurs while reaching the next printing portion by absorbing the dampening water applied during the previous printing is It pulls from the downstream side of the printing unit while generating appropriate corrugations substantially parallel to the longitudinal direction of the printing unit, and reduces and offsets the space between both sides of the paper (that is, the width direction of the web paper) when passing through the next printing unit. As a result, the lines of the web material that are overprinted by the plurality of printing units are aligned, and the printed image is properly aligned.

[0012]

EXAMPLES Next, examples of the present invention will be described with reference to FIGS. FIG. 1 shows an embodiment of the paper waving towing means 1. In the figure, reference numeral 11 denotes an uneven traction roller having an uneven peripheral surface. The concave-convex traction roller 11 is an auxiliary roller so that the wrapping angle α (see FIG. 4) sufficient to pull the traveling web material W can be secured on the downstream side of the printing unit P so as to contact the web material W. 12 and the like, the shaft end of which is automatically controlled so as to maintain a predetermined relationship with the operating speed of the planographic rotary printing machine PM, and the predetermined relationship can be adjusted appropriately. The uneven surface pulling mechanism 10 is linked to the body 13.

FIG. 2 shows another embodiment of the paper corrugated traction means 1. 21 is a pulling roller. The pulling roller 21 is arranged on the downstream side of the printing section P together with the auxiliary roller 22 and the like so that the winding angle β sufficient to pull the traveling web material W can be secured and the web material paper W can be contacted. , Its shaft end is linked to a rotary driving body 23 whose operating speed is automatically controlled so as to maintain a predetermined relationship with the operating speed of the planographic rotary printing press PM and which can appropriately adjust the predetermined relationship. The pulling mechanism 20 is configured.

Further, between the traction roller 21 and the printing section P, an uneven roller 26 having an uneven peripheral surface is run while being pulled by the traction roller 21.
Further, the pressing mechanism 25 is provided so as to be able to come into contact with the uneven peripheral surface and to be rotated as the web material W travels. The concave-convex traction roller 11 and the concave-convex roller 26 in the concave-convex surface traction mechanism 10 and the pressing mechanism 25 shown in FIGS. 1 and 2 are configured as shown in FIG. 3, and the convex portion 27 having a gentle arcuate top is formed in the axial direction. It has a shape in which a plurality is provided.

The operation of the above-described embodiment shown in FIGS. 1 and 2 will be described. In the paper corrugated traction means 1 shown in FIG. 1, the concave-convex traction roller 11 is provided with blanket cylinders BC, BC whose peripheral surface speed of the convex portion 27 is the printing portion P, P '.
The rotational driving body 1 is set to be slightly faster than the peripheral surface speed of
It is rotationally driven by 3. By this drive, the web material paper W is towed by the uneven traction roller 11 by the traction force generated by the frictional force between the peripheral surface of the roller and the web material paper W. By this pulling, the web material W strongly contacts the concave-convex towing roller 11, and the wavy WA that is substantially parallel to the longitudinal direction is generated on the web material W.

In the paper corrugated traction means 1 shown in FIG. 2, the traction roller 21 is rotated so that the peripheral speed thereof is slightly higher than the peripheral speeds of the blanket cylinders BC, BC of the printing units P, P '. It is rotationally driven by the dynamic driving body 23. By this drive, the pulling roller 21 pulls the web material W by the pulling force generated by the frictional force between the peripheral surface of the pulling roller 21 and the web material W. By this pulling, the web material W becomes in a strongly stretched state and strongly contacts the uneven roller 26 provided between the pulling roller 21 and the printing portion P, and the web material W is substantially parallel to the longitudinal direction thereof. A wavy WA occurs.

In any of the embodiments shown in FIGS. 1 and 2, the web material W having the wavy WA is located at the center of the web material W on the downstream side of the printing section P as shown in FIG. Tension A in the longitudinal direction slightly inclined to the line CL side
Acts on the upstream side of the printing portion P, and the tension B in the longitudinal direction parallel to the center line CL of the web material W acts. Then, in the printing section P, the component C of the tension A and the tension B acts on the web material W.

Therefore, the web material paper W moves toward the center side by the action of the component force C while running, and is stabilized in a state where the component force C disappears and the tension A and the tension B act on the same straight line. As shown in FIG. 5, printing is performed by passing through the printing unit P in a state where the both sides of the paper are shortened. That is, in the planographic rotary printing press PM as shown in FIG. 4, the planographic rotary printing press PM is operated to run the web material W, and the printing units P and P ′ are printing-operated.

The web material W running by the operation of the planographic rotary printing press PM first reaches the printing section P ', and then the printing section P'.
The printing line is printed, and dampening water is applied from the non-printing area of the printing plate through the blanket surface of the blanket cylinder BC. The web material paper W provided with dampening water is
With the passage of time, the fibers absorb water and expand in the width direction and run toward the next printing unit. The web material W, which is run toward the next printing unit P, is moved between both sides of the paper by the action of the component force C generated by the action of the paper waving and pulling means 1 provided on the downstream side of the next printing unit P. The distance is made shorter than the width of the actual web material W, and the printing portion P
Leading to.

The shortening amount is the magnitude of the component force C generated by the action of the paper corrugating / pulling means 1, for example, the operation of the rotary drive (not shown in FIG. 4) with respect to the operating speed of the planographic rotary printing press PM. By changing the predetermined relationship of the speed and changing the magnitude of the tension A, or by the uneven traction roller 11
Alternatively, a web material W of an uneven roller (not shown in FIG. 4)
It is possible to make an appropriate adjustment by changing the contact state with the wavy WA. For this shortening amount adjustment, automatic control means (not shown) is provided, and the brand information of the web material and the web material W are provided to this automatic control means.
Information related to the running speed of the
Rotation speed of the main motor that drives the
Input one or more pieces of information such as information on the deviation amount of the above-mentioned printing image line (for example, the difference between the deviation amount of the printing image line at the central portion and the deviation amount of the printing image line at the side of the web material W) However, the control signal can be automatically output by outputting a control signal to each operation adjusting means (not shown) based on the input information.

With the above adjustment, the web material paper W is reduced in the widthwise direction from the printing portion P'to the next printing portion P by
The dampening water applied in the printing portion P ′ is adjusted to an amount that cancels the widthwise expansion amount that occurs while traveling from the printing portion P ′ to the next printing portion P, and the next printing portion P is allowed to pass through. The
The image line of the printing unit P is printed in a state of being aligned with the image line of the previous printing unit P '. Further, the waviness WA caused by the paper undulating traction means 1 is generated substantially evenly in the width direction of the web material W, so that the shortening action is performed substantially evenly in the width direction of the web material W, and defects such as wrinkles that can be visually observed. Is also prevented.

According to the applicant's test, in a lithographic rotary printing machine in which printing units P1, P2, P3 and P4 as shown in FIG. 8 are stacked, the paper corrugating / pulling means 1 is provided downstream of the printing units P2, P3 and P4, respectively. A newspaper roll A (16
As a result of printing using the 26 mm width), when the printing is performed without providing the paper corrugating / pulling means 1, the deviation of the image lines of the printing portions P1 to P4 due to the expansion in the width direction caused by the water absorption of the web material W I was able to lose it. By the way, although the amount of expansion in the width direction differs depending on the brand of the paper roll, in the printing using the material paper waviness traction means 1, the printing portion P1 and the printing portion P4, which have occurred in the printing without the material paper waviness traction means 1, are performed.
It was possible to eliminate a deviation of about 2 mm between the printed image lines (using the newspaper roll A roll).

The present invention is not limited to the embodiments described above, and the uneven traction roller and the uneven roller may have any other suitable shape, and the uneven roller in the pressing mechanism presses the running web material. Other configurations may be used as long as they can effectively generate waviness. Further, the uneven traction roller and the traction roller should have a relatively large friction coefficient. Use of a material having a large wear coefficient and a surface configuration having a large wear coefficient may be freely selected and combined. The surface may be configured to be able to adsorb the web material. Further, in order to secure the winding angle of the web material on the uneven traction roller and the traction roller, the installation position of the auxiliary roller and the pressing mechanism may be appropriately determined, and the uneven traction roller, the traction roller, the auxiliary roller, the pressing mechanism, The installation position may be movable and adjustable. The point is that it includes design modifications that do not depart from the scope of the claims.

[0024]

According to the present invention, even when two or more lithographic printing sections using dampening water are used to successively print on the same web material, the web is cut from the preceding printing section to the next printing section. The width of the paper stock was adjusted to offset the expansion of the web paper in the width direction due to water absorption.Therefore, the web paper that is generated by absorbing the dampening water that is applied at the same time as printing in the printing section during printing run. It is possible to eliminate the deviation between the previously printed printing line and the subsequent printing lines due to the expansion in the width direction of the. Therefore, it has become possible to obtain a printed matter of good quality.

[Brief description of drawings]

FIG. 1 is a schematic configuration explanatory view showing an embodiment of the present invention.

FIG. 2 is a schematic configuration explanatory view showing another embodiment of the present invention.

FIG. 3 is a perspective view showing an example of shapes of an uneven traction roller and an uneven roller.

FIG. 4 is a front view showing a schematic configuration of a lithographic rotary printing press including two printing units stacked together and provided with the web material width adjusting device shown in FIG. 1.

FIG. 5 is an explanatory view showing the operation of the web material width adjusting device of the present invention and showing a state in which a component force acts on the center line side together with tension in the traveling direction on the downstream side of the printing unit.

6 is an explanatory view showing an operation of the web material width adjusting device of the present invention and showing a state in which the component force toward the center line side shown in FIG. 5 disappears.

FIG. 7 is a front view showing a schematic configuration of a known lithographic printing press in which four printing units are stacked.

FIG. 8 is a front view showing a schematic configuration of a known lithographic printing press in which four printing units are stacked.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Rippling traction means for paper, 10 ... Traction mechanism for uneven surface, 11
... Concavo-convex traction roller, 12 ... Auxiliary roller, 13 ... Rotation drive body, 20 ... Traction mechanism, 21 ... Traction roller, 22 ...
Auxiliary roller, 23 ... Rotational driving body, 25 ... Pressing mechanism, 2
6 ... uneven roller, 27 ... convex portion, α, β ... winding angle, PM ...
Lithographic printing press, P, P ', P1, P2, P3, P4 ...
Printing section, BC ... Blanket cylinder, PC ... Plate cylinder, W ... Web paper, WA ... Rippling, CL ... Center line of web paper,
A, B ... tension, C ... component force.

Claims (3)

[Claims] 1. A web material width adjusting device, characterized in that, on the downstream side of a printing section, there is provided a paper material corrugating / pulling means for corrugating and drawing the web material paper substantially in parallel with its longitudinal direction. 2. The paper corrugated traction means has an uneven surface traction mechanism for drawing the web material paper by means of an uneven surface.
The described web material width adjusting device. 3. The corrugated paper traction means has, in order from the upstream side, a pressing mechanism that presses the web paper so as to generate unevenness in the width direction of the web paper, and a traction mechanism that draws the web paper. Web material width adjusting device.