JPH0323340B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a swing device in a rotary cylinder of a sheet-fed printing press that can be selectively switched between front printing and back printing.

The swinging device in this type of printing press has a suction swinger and a gripper swinger, the suction swinger receiving sheets from the surface of several cylinders or rolls in the case of front and back printing, and is delivered in a rotated state to a Gritspa swinger, which then inverts the paper and sends it further to the next cylinder.

Especially when printing at high speeds, when paper sheets are large in size, or when handling paper sheets ranging from thin paper to thick paper, it is important to The construction and control of the jonswinga is of particular importance.

A swinging device of this type with a grip swinger and a suction swinger is known from German Democratic Republic Patent No. 54703. This swing device has a gripper swinger and a suction swinger of the same length, the gripper swinger and the suction swinger are connected to each other and form an arc-shaped trajectory for the movement of a sheet guide cylinder (rotating cylinder). Draw and rotate. In this case, in the known device, the swing (rotation) angles of both swingers are made equal.

A disadvantage of the known swinging device is that when the suction swinger is rotated, a deflection angle is formed between the surface of the suction head and the sheet released from the impression cylinder. This deflection angle causes a reduction in the holding force of the suction swinger. In particular, when handling cardboard-like sheets, this deflection angle causes the sheet to be peeled off from the suction head and bent adjacent to the holding surface of the suction member.

This drawback occurs when the tensile force increases, such as when the printing press is operated at high speeds, and this can cause misregistration. According to German Democratic Republic Patent No. 142 861, the following sheet reversing device is also known. That is, in this device, the suction swinger has a suction device, is movably supported by the suction swinger, and is rotated by a special control mechanism. Due to this additional movement, the deflection angle that occurs during rotation can be kept even smaller.

However, even with this method, a control drive device is required, and since the suction device is rotatably supported, the sheet reversing device becomes expensive and its control becomes more difficult. remains.

Furthermore, the addition of a drive increases the moving mass and the resulting inertia forces.

In view of the above points, it is an object of the present invention to maintain the register in both front and back printing, even when handling large-sized paper sheets and when operating at high rotational speeds. The object of the present invention is to provide a swing device for a rotary cylinder of a sheet-fed printing press, which is capable of performing a reversal.

According to the invention, in a swing device for a rotary cylinder of a sheet-fed printing press, the suction swinger and the gripper swinger are arranged so that no deflection angle occurs between the suction surface of the suction swinger and the paper sheet.

In the present invention, in order to prevent a deflection angle from occurring, the distance from the attraction surface of the suction swinger to the center of the swing axis of the suction swinger is the same as the distance from the grip contact surface of the gripper swinger to the center of the swing axis of the gripper swinger. made smaller.

The above-described novel geometrical arrangement of the suction swinger and the gripper swinger results in a favorable overall form of displacement during leaf reversal. On the other hand, due to the geometrical dimensional relationships described above, in the preferred embodiment, the swing angles PSI _S of the suction swinger and the grip swinger are
The PSI _G relationship is 2:1 or 3:1. The distance r _S from the center of the swing axis of the suction swinger to the suction swing suction surface is smaller than the ratio of the distance r _S from the center of the swing axis of the gripper swinger to the contact surface of the gripper _G , and the swing angle PSI of the gripper swinger is smaller than 1. By configuring the swinging device under the condition that the ratio of the swing angle of the swinger to the swing angle PSI _S is less than 1, it is possible to avoid the formation of deflection angles during the rotation, and under normal conditions the paper The leaves can be pulled out of the front cylinder. In particular, a device for controlling the position of the suction head during the travel of the sheet is no longer necessary, so that the suction swinger
This simple structure requires less mass than the Gritspa swinger.

The suction swinger and the grip swinger are operatively connected to each other, and the distance r _G >
r _S , by setting the above-mentioned swing angle PSI _S > PSI _G , it is possible to avoid the formation of a sheet deflection angle without adding a control mechanism to the suction head, and to By the time the leaf is delivered by the suction swinger,
The gripper swinger has already traveled a part of the swing angle PSI _G , so that a position is obtained in which the gripping tip of the opened gripper is below the cylinder circumferential surface. Therefore, the rotation angle of the massed Gritspass swinger relative to the suction swinger is kept small, so that the rotation stroke of the swing device takes on a favorable state over a large rotation angle of the sheet reversing cylinder. be able to.

As described above, according to the present invention, the performance of the printing press can be improved with a simple and reliable configuration.

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 designates a rotary cylinder of a front-to-back printing press. Both the rotating cylinder 1 and the swing device consisting of the suction swinger 2 and the grip swinger 3 belong to the public domain, such as in German Democratic Republic Patent No. 54703, and are not the gist of the present invention. . The rotating cylinder 1 includes a first cylinder 4.1 (Figs. 2 and 3) and a second cylinder 4.2.
(Fig. 3) on both sides. These cylinders 4.1, 4.2 can be designed as impression cylinders or sheet-guiding cylinders. The suction swinger 2 and the grip swinger 3 are supported by swing shafts (pivots) 5.1 and 5.2, respectively.
These swing axes are supported by rotary cylinders 1 and effect a swinging movement by means of suitable drives and transmissions. Furthermore, in order to transfer the sheet from the suction swinger 2 to the grip swinger 3, the distance between the swing shaft 5.1 and the swing shaft 5.2 is r _S +r _G. The drive device can be of the type disclosed in German Democratic Republic Patent No. 59799, and the swing axis 5
may be coupled via sector gears or may drive each swing axis separately, as disclosed in German Democratic Republic Patent No. 127935.

The gripper swinger 3 includes a gripper contact member 6 having a gripper contact surface 7 and a gripper tongue 8 , and the gripper tongue 8 is supported by a gripper shaft 9 . Suction swinger is suction part 1
0, and a suction surface 11 is provided thereon.

The distances from the center of the swing axis 5 to the gripper contact surface 7 and suction surface 11 are r _G and r _S , respectively (FIG. 1).

During the paper sheet guiding action of the suction swinger 2 and the gripper swinger 3, these swingers 2, 3
rotate through swing angles PSI _S and PSI _G , respectively.

According to the invention, r _S is made smaller than r _G and
PSI _G is defined as smaller than PSI _S.

The operation of the printing press of the present invention in front printing and back printing is as follows.

Gritspa Swinga 3, its swing angle
When the sheet is transferred across PSI _G and sent to the second cylinder 4.2 as shown in FIG. From swing axis 5.1
The position is rotated by a predetermined angle in the direction of rotation of the cylinder from the line passing through the cylinder.

The sheet 12 being fed on the first cylinder 4.1 then travels along the tangent t _1.2 (third
2, the rear end edge is grasped by the suction swinger 2 which rotates by the predetermined angle in the direction opposite to the direction of rotation of the cylinder (FIG. 2).

The suction swinger 2 grasps the rear edge of the paper edge 12 and rotates from this position around the swing axis 5.1 in a direction opposite to the direction of rotation of the cylinder.
It angularly displaces by its total swing angle PSI _S and reaches the new position. In this position, as shown in FIG. 2, the suction surface 11 of the suction unit 10 is parallel or almost parallel to the sheet 12, and there is no deflection angle. At this position, the sheet of paper 12 adsorbed by the suction swinger 2 is held by the gripper swinger 3, which rotates in the rotational direction of the cylinder, as shown in _FIG . The paper sheet 12 is then transferred to the second cylinder 4 as shown in FIG.
Send to 2.

This type of printing press has been known for many years;
It was described in German Democratic Republic Patent No. 54703 (1966). However, from the center of the suction swinger shaft 5.2 to the suction swinger suction surface 11.
By simply making the distance r _S to be smaller than the similar distance r _G in the Gritzpa swinger and thereby increasing the swing angle PSI _S of the suction swinger with respect to the swing angle PSI _G of the Gritzpa swinger 3, No one noticed that it worked or was effective.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the geometrical relationship of the swinging device of the rotary cylinder of the sheet-fed printing press of the present invention, FIG. 2 is a schematic diagram showing the delivery and guidance state of paper sheets by the suction swinger, and FIG. 1 is a schematic diagram showing the situation of sheet transfer in the area of a rotating cylinder and a following cylinder; FIG. 1...Rotating cylinder, 2...Suction swinger, 3...Gritzpa swinger, 4.1...First cylinder, 4.2...Second cylinder, 5.1...Swing axis of suction swinger, 5. 2... Swing axis of the gripper swinger, 6... Gripper contact member, 7... Contact surface, 8... Gripper tongue,
9... Axis pin of Gritspa Swinger, 10... Adsorption part, 11... Adsorption surface, 12... Paper leaf, PSI _G ...
...the swing angle of the paper leaf of Gritspus moth,
PSI _S ...Swing angle of the suction swinger with respect to the paper sheet, r _G ...Distance between the center of the swing axis and the contact surface of the gripper, r _S ...Distance between the center of the swing axis and the suction surface, t ₁ , ₂ ... Tangent line between the first cylinder and the rotating cylinder.

Claims (1)

[Claims] 1 A swing shaft for a suction swinger and a swing shaft for a gripper swinger are provided on the rotating cylinder at intervals in the rotational direction of the rotating cylinder, and a suction swinger having a suction surface at its tip is pivotally attached to the swing shaft for the suction swinger. At the same time, a Gritsupas swinger with a grip contact surface at its tip is pivotally attached to the swinging shaft for the Gritsupas swinger, and can be selectively switched between front printing and back printing, and paper sheets are printed on the front side by the principle of turning the trailing edge over. In a swing device for a rotary cylinder of a paper sheet printing press that can be freely reversed for reverse printing, the distance from the suction surface 11 of the suction swinger 2 to the center of the swing shafts 5 and 1 for the suction swinger is r _S The distance from the grip contact surface 7 of the Gritspa swinger 3 to the center of the swing shafts 5 and 2 for the Gritspa swinger is r _G , and the swing angle of the Gritspus swinger is
PSI _G , the swing angle of the suction swinger.
When PSI _S is set, r _S is smaller than r _G , and PSI _G is
This swing device is smaller than PSI _S , and is characterized in that the distance between the center of the swing shafts 5, 1 for suction swingers and the centers of swing shafts 5, 2 for grippus swingers is set to _rS plus _rG .