JPH0434032Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention is a sheet-fed printing press with a reversing mechanism.The present invention is a sheet-fed printing press with a reversing mechanism. It is related to the device.

[Conventional technology]

With the diversification of printing, various types of sheet-fed printing presses with reversing mechanisms that can be used for single-sided printing and double-sided printing have been proposed and put into practical use. There are two main types: a one-piece type with a double-diameter reversing cylinder, and a three-piece type with a transfer cylinder, a reversing cylinder, and a double-diameter cylinder between them.

Among these, the double-diameter barrel of the three-piece type has a plurality of gripping claw devices (hereinafter referred to as claws) consisting of a claw and a claw base arranged in parallel in the axial direction at positions that bisect the outer circumferential part into two equal parts. Two rows of suction heads are provided, and a plurality of two rows of suction heads are provided at positions dividing the outer circumferential portion into two, with the suction heads being out of phase with the claws in the circumferential direction.

In the case of single-sided printing, the paper printed in the first color is transferred from the transfer cylinder's claw to the double-diameter cylinder's claw, is conveyed while attached to the double-diameter cylinder, and is then transferred to the reversing cylinder's claw. After being transferred and conveyed, the second color is printed. In such single-sided printing,
Paper is conveyed with its tip caught in the claws of the double-diameter cylinder,
The end of the paper is suctioned by the suction head and conveyed so that the unheld portion other than the end of the paper does not flap.

In addition, in the case of double-sided printing, the paper that has been printed on the front side is transferred from the transfer cylinder's grip to the double-diameter cylinder's grip, as in single-sided printing, and then transferred to the reversing cylinder's grip. The animal is transferred in its mouth. In this case, the double-diameter cylinder rotates the length of the paper in the vertical direction more than in the case of single-sided printing, and the claws of the reversing cylinder grip the end of the paper and transport it, resulting in the paper being reversed and then printed. The unit prints on the back side of the paper, making it double-sided. Even in the case of such double-sided printing, when the paper is conveyed with its leading edge caught in the claws of the double-diameter cylinder, the suction head is used to suck the trailing edge of the paper so that the unheld portion other than the gripped edge does not flap. At the same time, when the paper is transferred to the claw of the reversing cylinder, the suction head sucks the trailing edge of the paper until the claw finishes picking up the trailing edge of the paper, thereby ensuring the re-gripping.

In double-sided printing using such a sheet-fed printing press with a reversing mechanism, when the paper is transferred from the suction head of the double-diameter cylinder to the claw of the reversing cylinder, the tail of the paper suctioned by the suction head may sag in the vertical or horizontal direction. When you are there,
When printing on the back side, printing errors occur due to misregistration, so various paper edge tensioning devices have been proposed for tensioning the paper being sucked by a suction head.

[Problem that the invention attempts to solve]

However, the following problems remain in the conventional paper tail tensioning device. That is, for example, the paper disclosed in Japanese Patent Publication No. 44-9056 rotates the fan-shaped side plate that holds all the suction heads around the double-diameter axis until it hits a stopper to smooth out the wrinkles in the paper. However, since wrinkles are smoothed only in the vertical direction of the paper, the paper may sag from side to side, making it impossible to completely eliminate printing misregistration.

Further, for example, in the device disclosed in Japanese Patent Publication No. 54-30323, each suction head is rotatably supported, and its suction port is eccentric to the center of rotation, and the suction head is rotated at any time by a cam mechanism. This device tensions the paper vertically and horizontally by moving the mouthpiece eccentrically, but it has a complicated structure and a large number of parts, which not only makes it impossible to provide at a low price, but also makes maintenance difficult. There was a problem with the lack of durability.

[Means for solving problems]

In order to solve these problems, in the present invention, a plurality of suction levers, which are pivoted in parallel on the intake pipe extending parallel to the cylinder axis on the outer periphery of the double-diameter cylinder, have a The suction head is rotatably supported, and its protruding end in the direction parallel to the cylinder axis is rotatably and slidably supported on the cylinder body side, and the suction port of the suction head that opens to the cylinder circumferential surface is aligned with the axis of the suction head. It is installed at an eccentric position in the circumferential direction of the cylinder, and has a cam on the frame side and a cam follower on the cylinder side, and as the cylinder rotates, the suction lever swings, and the suction head swings around the protruding end while rotating around the support part. A cam mechanism has been installed to allow

[Effect]

The tail of the paper transferred from the transfer cylinder's claw to the double-diameter drum's claw is attracted to the end surface of the suction head by the air sucked from the suction port of the suction head, and is reversed to the double-diameter cylinder. Move towards the point of contact with the torso.
During this movement, the rotating cam follower on the side of the double-diameter cylinder comes into contact with the cam surface of the fixed cam on the frame side, the suction lever swings, and the suction head swings around the protruding end and moves to the center of the support part. As it rotates, the suction port provided at the eccentric position of the suction head moves in an oblique direction that has both axial and circumferential components of the cylinder.
Tension the tail of the paper being sucked in both directions, vertically and horizontally.

〔Example〕

1 to 7 show an embodiment of the paper tail tensioning device according to the present invention. Figure 3 is a side view from B of Figure 1, Figure 4 is a side view of Figure 2.
Fig. 5 is a plan view corresponding to Fig. 2 with the paper end under tension, Fig. 6 is a schematic plan view of a double diameter cylinder implementing the present invention, and Fig. 7 is a cross-sectional view of the CC section of the figure. FIG. 2 is a cylinder arrangement diagram of a printing press shown to explain a double-sided printing operation. In the figure, diagonally below the blanket cylinder 1 that is in contact with the plate cylinder, there is an impression cylinder 5 equipped with a gripping claw device 4 (hereinafter referred to as the claw 4) consisting of a claw 2 and a claw base 3 in a notch on the outer periphery. The printing unit on the downstream side also has a blanket cylinder 6 which is provided so that its peripheral surfaces are in contact with each other and which is in contact with the plate cylinder.
and an impression cylinder 10, which is provided with a gripping claw device 9 (hereinafter referred to as claw 9) consisting of a claw 7 and a claw base 8, and whose peripheral surface is in contact with the blanket cylinder 6. Between both impression cylinders 5 and 10, there is provided a transfer cylinder 1 whose peripheral surfaces are in contact with each other.
A reversing mechanism consisting of three rollers: 1, a double diameter cylinder 12, and a reversing cylinder 13 is provided. Of these, the transfer drum 11 is provided with a gripping claw device 16 (hereinafter referred to as the claw 16) consisting of a claw 14 and a claw base 15 in an outer peripheral notch. Also, the double diameter cylinder 12 is the transfer cylinder 11.
Two sets of gripping claw devices 19 and 20 (hereinafter referred to as claws 19 and 20) consisting of a claw 17 and a claw base 18 are located at positions dividing the outer circumference into two equal parts.
Two rows of suction heads 36, which will be described later, are arranged at a position that precedes each claw 19, 20 by a predetermined angle in the direction of rotation of the cylinder. Double diameter barrel 12
The configuration will be explained in detail later. Furthermore, reversal cylinder 1
In the outer peripheral notch of No. 3 is a gripping claw device A25 (hereinafter referred to as claw A25) consisting of a claw 23 and a claw base 24.
and a gripping claw device B2 consisting of a claw 26 and a claw base 27.
8 (hereinafter referred to as claws B28) are disposed adjacent to each other in the circumferential direction.

The double diameter barrel 12 is formed of a barrel main body 29 having a casting space, and side plates 30 on both sides joined to both end surfaces of the barrel body 29 and fixed in a rotatable manner.
End shaft portions at both ends of the trunk body 29 are pivotally supported by frames on both sides. An intake pipe 31 extending parallel to the body axis is pivotally supported by the side plates 30 on both sides at a location where the outer periphery of the side plates 30 on both sides is equally divided into two in the circumferential direction. It is connected to a vacuum pump as an air source via a rotary valve (not shown). On the other hand, a plurality of grooves 32 having a predetermined circumferential angle are provided in parallel in the axial direction on the outer peripheral wall of the trunk body 29, and in each groove 32, a suction lever 33 extending in the trunk circumferential direction is provided. are fixed to the intake pipe 31 with separate fastenings, respectively. Each suction lever 33 has an intake hole 33a that passes through its axial center and communicates with the inner hole of the intake pipe 31, and a switching valve 35 that opens and closes the intake hole 33a by gripping a knob 34 and rotating it. A circular convex portion 36a of a suction head 36, which is formed in a potbellied shape when viewed from above, is rotatably fitted into a circular concave hole 33b provided on the distal end surface of the suction lever 33. This suction head 36 includes a pot-shaped main body 36b having a circular convex portion 36a, and a main body 36b.
Diamond-shaped adsorption plate 36 screwed to the end face of 6b
This suction head 36 is integrally formed with
is prevented from coming out of the recessed hole 33b by a guide 37 screwed to both sides of the suction lever 33 and having an L-shaped cross section. is in contact with
Further, the main body 36b of the suction head 36 is provided with a stepped intake hole 36d that is continuous with the intake hole 33b of the suction lever 33, and a suction plate 36c.
is provided with a suction port 36e that communicates with the intake hole 36d and opens toward the circumferential surface of the trunk. The position of this suction port 36e is set at an eccentric position in the circumferential direction that precedes the rotation axis of the suction head 36 in the direction of rotation of the cylinder as shown by arrow D in the figure. Reference numeral 38 denotes a U-shaped holder fixed to the wall surface of the groove 32 with a bolt 39, and the U-shaped groove 38a has a roller 40 pivotally attached to the protruding end of the main body 36b of the suction head 36. are rotatably and slidably engaged. A cam lever 41 is pivotally attached to a protruding portion of the intake pipe 31 from one side plate 30, and a cam follower 42 is pivotally attached to its free end. On the other hand, a cam 43 having a small diameter part 43a and a large diameter part 43b is fixed to the machine frame side, and the cam follower 42 is pressed against the cam surface of this cam 43 by a spring member (not shown). 12 rotates, the cam follower 42 moves from the large diameter portion 43b to the small diameter portion 43a of the cam 43 at a predetermined position during one rotation, and the cam lever 41 swings to connect each suction unit to the cam lever 41 via the intake pipe 31. The lever 33 is configured to swing. and,
When the suction lever 33 swings, the guide 37 moves in the circumferential direction of the cylinder, and the suction head 36, which holds the suction plate 36c therebetween, also moves. However, the torso body 2
Since the suction head 36 is held by a fixed holder 38 on the 9 side, the suction head 36 has a roller 40 which is a protruding end.
It rotates around the circular convex portion 36a, which is a support portion, while swinging around the center. That is, since the suction head 36 moves between the position shown in FIG. 2 and the position shown in FIG. 5, the suction port 36e moves from the solid line position to the chain line position in FIG. The amount of movement to is indicated by the symbols X and Y in FIG. 2, respectively. Therefore, the intake pipe 31
The paper that is attracted to the suction plate 36c by suction from the side is pulled and tensed in a direction that lags behind the rotational direction of the cylinder and in an outward direction of the cylinder axis. It should be noted that among the plural suction heads 36, the one provided at the right end and the one provided at the left end of the double diameter cylinder 12 are symmetrical with each other, and the paper has both left and right ends facing outward. It is pulled diagonally.

A double-sided printing operation by a sheet-fed printing press with a reversing mechanism having a double-diameter cylinder configured as described above will be explained. When each cylinder rotates in the direction shown by the arrow in FIG.
When the paper 50 passes between the blanket cylinder 1 and the impression cylinder 5, the first color is printed on its surface. This paper 50 is
During this transportation, the vacuum pump operates and the atmosphere outside the suction port is transferred to the suction port 36e, the intake holes 36d, 33a, Since the paper 50 is sucked through the intake pipe 31 and the rotary valve, the paper end of the paper 50 is absorbed by the suction plate 36.
It is adsorbed by c. When the tail of the paper approaches the contact point between the two cylinders 12 and 13 due to the rotation of the cylinder, the cam follower 42 moves from the large diameter part 43b of the cam 43 to the small diameter part 43a, and the suction lever 33 moves as shown in FIG. Since it rotates clockwise, the suction head 36, which holds the protruding end roller 40 with the holder 38,
The suction port 36e moves from the position shown in FIG. 2 to the position shown in FIG. 5 by pivoting around the circular convex portion 36a while swinging around the center. That is, since the suction port 36e moves by X in the axial direction and by Y in the circumferential direction, the tail of the paper 50 attracted to the suction port 36e is pulled obliquely outward at both left and right ends, and is moved in the vertical and horizontal directions. I get nervous. When the tensioned paper 50 is conveyed in this manner until the tail of the paper reaches the contact point between the cylinders 12 and 13 as shown by reference numeral 50A in the figure, the claw B28 closes and grips the tail of the paper, and the suction head 43 releases the paper tail from suction, so paper 5
The paper 0A is conveyed by the reversing cylinder 13 with the tail end of the paper leading. When the end of the paper is changed in the mouth, the paper 50A is tensed vertically and horizontally, so the nail B28 grips the correct part. Then, during conveyance by gripping the pawl B28, both pawls A25 and B28 are reversed and then open and close at different timings, causing the paper 50A to
is changed from claw B28 to claw A25 and claw A2
5. After being reversed at B28, it is transported. When the pawl A25 and the pawl 9 of the impression cylinder 10 face each other, the paper 50A is gripped by the pawl 9 and conveyed as shown by reference numeral 50B in the figure. When this paper 50B passes between the blanket cylinder 6 and the impression cylinder 10, the back side comes into contact with the blanket cylinder 6, so printing is performed on the back side and printing on the front side results in double-sided printing. When printing on the back side, the paper 50A is correctly gripped by the claws B28 while being tensed both vertically and horizontally, so that printing misregistration does not occur.

[Effect of idea]

As is clear from the above explanation, according to the present invention, in a paper tail tensioning device for a sheet-fed printing press with a reversing mechanism, shafts are attached in parallel on the outer periphery of a double-diameter cylinder on an intake pipe extending parallel to the cylinder axis. A suction head is rotatably supported on the tip surface of each of the plurality of suction levers, and the protruding end in the direction parallel to the cylinder axis is rotatably and slidably supported on the cylinder body side, and The opening of the suction head is provided at an eccentric position in the circumferential direction of the suction head with respect to the axis of the suction head, and it has a cam on the frame side and a cam follower on the cylinder side, and the suction lever is swung by rotation of the cylinder to project the suction head. By providing a cam mechanism that rotates around the support part while swinging around the center of the end, the end of the paper that is being conveyed by being gripped by the claws of the double-diameter cylinder is attracted to the suction head, and the paper is conveyed. During the process, the suction head moves diagonally outward due to the operation of the cam mechanism and the swinging action of the suction head, pulling the suctioned paper tail diagonally outward and tensioning it in both the vertical and horizontal directions. Since the correct position is held in the claw of the side impression cylinder, printing misregistration will not occur in subsequent printing.
The quality of printed matter is greatly improved, the structure is simple and maintenance is easy, and this can be provided at low cost. Furthermore, forced load can be avoided during rotation of the suction head, making it possible to cope with higher speeds.

[Brief explanation of drawings]

1 to 7 show an embodiment of the paper trailing tension device for a sheet-fed printing press with a reversing mechanism according to the present invention, and
The figure is a cross-sectional view of the outer circumference of the double-diameter barrel in which this process was implemented, and the second
The figure is a plan view from A in Fig. 1, Fig. 3 is a side view from B in Fig. 1, Fig. 4 is a CC cross-sectional view in Fig. 2, and Fig. 5 shows the second FIG. 6 is a schematic plan view of a double-diameter cylinder embodying the present invention, and FIG. 7 is a cylinder arrangement diagram of a printing press shown to explain the double-sided printing operation. 12...Double diameter barrel, 29...Body body, 31...Intake pipe, 33...Adsorption lever, 33a, 36d...
Intake hole, 33b...circular concave hole, 36...suction head, 36a...circular convex portion, 36c...suction plate, 3
6e... Suction port, 37... Guide, 38... Holder, 40... Roller, 42... Cam follower, 43
……cam.

Claims (1)

[Scope of utility model registration request] An intake pipe supported on the outer periphery of the double-diameter barrel in parallel with the axis and connected to an air source, a plurality of suction levers that are pivoted in parallel on this intake pipe and extend in the circumferential direction of the barrel, and In a sheet-fed printing machine with a reversing mechanism, which is equipped with a paper tail suction device consisting of a suction head that is attached to the tip of a suction lever and has a suction port that opens toward the cylinder circumferential surface, the suction head is attached to the cylinder circumferential surface of the suction lever. The suction port is supported rotatably around the radial axis of the suction head, and its protruding end in a direction parallel to the cylinder axis is rotatably and slidably supported on the cylinder main body side, and the suction port is aligned with the cylinder circle relative to the axis of the suction head. The suction head is provided at an eccentric position in the circumferential direction, and has a cam on the frame side and a cam follower on the double diameter cylinder side, and the suction lever is swung by the rotation of the double diameter cylinder, and the suction head is supported while being swung around the protruding end. A paper edge tensioning device for a sheet-fed printing press with a reversing mechanism, characterized by being provided with a cam mechanism that rotates around the center of the sheet-fed printing press.