EP1609598B1 - Method for reliable driving a printing press and printing press using this method - Google Patents

Abstract

The process involves including a printing machine containing two cylinders driven by respective motors. Sheets of paper are accepted or delivered from or to the one of the cylinders by a gripper system (27). The gripper system is retracted far enough into one of the cylinders such that collision of the gripper system with the other cylinder is eliminated when deviation occurs in synchronized running between the cylinders. An independent claim is also included for a printing machine comprising two cylinders driven by respective motors.

Description

The present invention relates to a method for safe operation of a printing press, wherein a first cylinder is driven by a first motor and a second cylinder by a second motor and the first cylinder by means of a gripper system takes over sheet from the second cylinder or passes to the latter The present invention further relates to a printing press for carrying out the method, comprising a first cylinder with a gripper system, a first motor for driving the first cylinder, a second cylinder and a second motor for driving the second cylinder the preamble of claim 2.

The invention arose from the following background: sheetfed presses comprise cylinders with gripper systems for holding the sheets. In some sheet-fed presses, such cylinders, which are adjacent to each other, are mechanically coupled together by a pair of gears, so that the cylinders can be driven by a common motor. By the pair of gears, the cylinders are coupled formschlüssüsig that under all circumstances synchronous operation of the cylinder is ensured with each other and a collision of a gripper system of one cylinder is excluded with the other cylinder.

But there are also sheet-fed presses, in which the cylinders have no such gear pair and are driven by different motors. As long as the motors work trouble-free, the synchronous operation of the cylinders is ensured and thus a collision of the gripper system is excluded. In order to avoid such a collision even in the case of a malfunction of one of the motors or its control, additional precautionary measures are required.

These precautionary measures can z. B. in that the in DE 42 02 722 A1 described safety device is present. However, the method by which this safety device works is not suitable for every printing press.

Far further state of the art represents an in DE 199 09 686 A1 described device for controlling the gripper, in which the grippers are pivoted under the periphery of a counter-pressure cylinder to perform maintenance.

The invention has for its object to provide a further method for safe operation of a printing press, are avoided in which collisions of the gripper system due to disturbances occurring in the printing operation, and to provide a suitable method for performing the printing press.

This object is achieved by a method having the features of claim 1 and by a printing press having the features of claim 2.

The inventive method for safe operation of a printing press, wherein a first cylinder by a first motor and a second cylinder are driven by a second motor and the first cylinder by means of a gripper system takes over arc from the second cylinder or passes to the latter, characterized in that the Gripper system is at least partially and so far retracted in a occurring between the cylinders synchronism deviation in the first cylinder that a collision of the gripper system is prevented with the second cylinder.

The sinking of the gripper system is carried out in the method according to the invention thus in response to the exceeding of a predetermined rotation angle difference, in which threatens the collision of the gripper system.

The printing press according to the invention for carrying out the method comprises a first cylinder with a gripper system, a first motor for driving the first cylinder, a second cylinder and a second motor for driving the second Cylinder and is characterized in that the first cylinder has a sinking mechanism for forcing occurring between the cylinders synchronous deviation occurring forcing the gripper system in the first cylinder.

In the printing machine according to the invention, the two cylinders are mechanically decoupled from each other and either the entire gripper system including the gripper and the gripper pad or only a part of the gripper system, z. B. only the gripper, at least as deep drawn into the first cylinder that the collision of the gripper system is prevented with the second cylinder.

In the subclaims mentioned developments of the printing machine according to the invention are briefly explained in detail below:

In a refinement, the countersink mechanism comprises a first shifting device rotating with the first cylinder, and the second shifting device is associated with the second cylinder in such a way that when the synchronism running deviation occurs, the shifting devices come into switching contact with one another. As soon as the synchronous operation between the cylinders is disturbed, the synchronous operation between the control devices rotating with the cylinders is also disturbed and, after exceeding a predetermined rotational angle difference between the cylinders and thus between the switching devices, come into switching contact with each other.

In a further development, the second switching device has a first flank and a second flank, which are arranged opposite one another in the direction of rotation and with play for the first switching device, which contactlessly engages in the second switching device during trouble-free synchronous operation. As long as the predetermined by the game rotation angle difference between the switching devices is not exceeded, the first switching device immersed in each revolution in the second switching device, without coming into switching contact with one of the two edges of the second switching device.

In a further embodiment, the first switching device is a shift lever which is arranged such that the shift lever is pivotable due to a switching contact between the shift lever and the first edge in the same direction of rotation as a result of a switching contact between the shift lever and the second edge. The shift lever or a cam follower, which has the shift lever, and the flanks of the second switching device are so arranged coordinated and contoured that the shift lever in both cases - the contact of the cam follower with the first edge and the contact of the cam follower with the second Edge - pushed by the respective edge in one and the same direction of rotation.

According to a further development, the second switching device is a safety curve. This safety curve is arranged coaxially with the second cylinder and rotatably connected to the latter.

In a further development, the first switching device for actuating a control system controlling the gripper cam is arranged. This control curve serves as a so-called gripper opening curve during trouble-free synchronous operation to adjust a gripper of the gripper system relative to the gripper pad, and allows in case of occurrence of the synchronism deviation to sink the gripper and the gripper pad in the first cylinder to a collision of the gripper with to avoid the second cylinder.

According to a further embodiment, the control cam is supported during trouble-free synchronous operation by a cam support, which is arranged such that when the synchronism deviation occurs, the first switching device strikes due to their switching contact with the second switching device to the curve support and thereby adjusted so that the curve support an adjustment the control cam releases. Accordingly, the first switching device is adjusted relative to the first cylinder as a result of their switching contact, that only then the curve support in an imaginary circle of the first Switching device, which flight circle describes the first switching device as a result of their rotation occurring together with the first cylinder, protrudes.

Other functionally and structurally advantageous developments will become apparent from the following description of preferred embodiments and the accompanying drawings.

Figur 1

ein Druckmaschinen-Zylinderpaar,

Figur 2

einen Greifersystem-Versenkmechanismus, mit dem jeder Zylinder des Paares aus Figur 1 ausgestattet ist, und

Figur 3

eine Modifikation des in Figur 2 dargestellten Versenkmechanismus.

In this shows:

FIG. 1

a printing press cylinder pair,

FIG. 2

a gripper system countersink mechanism, with which each cylinder of the pair off FIG. 1 is equipped, and

FIG. 3

a modification of the in FIG. 2 illustrated sinking mechanism.

In the in the FIGS. 1 and 2 illustrated embodiment, a printing machine 11 comprises a first cylinder 13 and a second cylinder 14. Each cylinder 13, 14 is a sheet 12 of substrate transporting cylinder, such as. B. a counter-pressure cylinder or a transfer drum. The first cylinder 13 is rotationally driven by a first motor 15 and the second cylinder 14 is driven by a second motor 16.

On the first cylinder 13, a first securing cam 17 and a first cam follower 19 are mounted and on the second cylinder 14 a second securing cam 18 and a second cam follower 20. The cam followers 19, 20 are rollers. Each locking curve 17, 18 has a recess 21 with a leading edge in the direction of rotation 22 and a trailing edge 23. Each cylinder 13, 14 has a cylinder channel 26 with a gripper system 27 disposed therein.

The respective gripper system 27 comprises a gripper 4 and a gripper pad 5, between which the sheet 12 is clamped during gripping. When gripping the sheet 12 of the gripper 4 is pivoted by a gripper shaft 11 to the gripper pad 5 out. This closing of the gripper system 27 and also the opening are controlled by means of a cam gear, to which a roller lever 2 and a control cam 7 belong. The roller lever 2 is rotatably connected to the gripper shaft 1 and carries a cam roller 3, which is held by a roller lever spring 24 on the control cam 7.

The clamping force of the gripper 4 is determined by a gripper spring 9, which is a compression spring and is biased between a mounted on the gripper shaft 1 and fixedly connected to the gripper 4 gripper housing 28 and a stop. The stop is firmly connected to the gripper shaft 1.

The gripper pad 5 is mounted in a substantially radial direction 29 inwardly displaceable in the cylinder 13 and 14 and loaded by a gripper support spring 8 in the opposite direction. The gripper support spring 8 is stronger, d. H. generating a larger spring force than the gripper spring 9. At the gripper pad 5, a pin-shaped driver 6 is arranged, which is contacted by the roller lever 2.

The control cam 7 is connected via a rotary joint 30 with a machine frame 31 and supported at its opposite end to the rotary joint 30 by a curve support 10. The curve support 10 is also pivotally connected to the machine frame 31 and adjustable by a shift lever 32 from a support position shown in solid line in a release position shown with phantom line. The shift lever 32 carries at one end of the cam follower 19 or 20 and contacted with its other end when switching the curve support 10. The shift lever 32 is pivotally mounted in the cylinder 13 and 14 and loaded by a return spring 25.

The function of in FIG. 2 shown sinking mechanism 35 is explained below using the example of its assignment to the first cylinder 13 below:

In trouble-free synchronous operation of the cylinders 13, 14 there is no risk that the gripper system 27 of the first cylinder 13 collides with the second cylinder 14 and engages the first cam follower 19 at each cylinder revolution in the trough 21 of the second locking curve 18, without touching the latter , This switching contactless cooperating the two switching devices (shift lever 32, second locking curve 18) is ensured by the present at the central engagement of the first cam follower 19 between the latter and the flanks 22, 23 game.

A disturbance of the synchronous operation can, for. B. in case of failure of one of the motors 15, 16 occur and involves the risk of a collision of the gripper system 27 of the first cylinder 13 with the second cylinder 14 in itself, because the two cylinders 13, 14 are not coupled via a synchronous locking positively locking gear pair together rotationally are. This risk of collision becomes acute when a certain rotational angle difference between the cylinders 13, 14 is exceeded.

In case of disturbance of the synchronous operation of the first cam follower 19 no longer exactly centered in the trough 21 and comes the first cam follower 19 with the second locking curve 18 in switching contact. The arc length of the trough 21 or between the flanks 22 and 23 existing distance is such that the first cam follower 19 runs when exceeding the specific rotation angle difference depending on the direction of this synchronism deviation on one or the other edge 22 or 23.

As a result, the first cam follower 19 bearing shift lever 32 is deflected, due to its design and the inclination of the flanks 22, 23 in both cases - the contact with the leading edge 22 and the contact with the trailing edge 23 - in one and the same pivoting direction , ie with respect to FIG. 2 clockwise.

The shift lever 32 consequently strikes with its first cam follower 19 opposite lever arm on the curve support 10 and pushes it out of their Supporting position out, so that the cam support 10, the control cam 7 releases and the latter with respect FIG. 2 can be folded down.

The roller lever spring 24 presses on the roller lever 2 and thereby contacted by the roller lever 2 driver 6, the gripper pad 5 against the action of the gripper pad spring 8 into the cylinder inside. As a result of the associated movement of the gripper shaft 1 and the action of the gripper spring 9, the gripper 4 of the retraction movement of the gripper pad 5 follows so far that the gripper 4 can no longer collide with the second cylinder 14. The gripper system 27 remains after the activation of the retracting mechanism over several revolutions of the first cylinder 18 and permanently retracted until the deactivation of the retracting mechanism.

For the purpose of deactivating the retracting mechanism, the curve support 10, z. B. by means of an actuator, zurückverstellt back to its supporting position, whereby the control cam 7 is folded upwards and is pivoted back by the control cam 7 of the roller lever 2 against the action of the roller lever spring 24, so that the gripper support spring 8, the gripper pad. 5 can zurückverstellen opposite to the direction 29.

Likewise, as with the aforementioned retracting mechanism for retracting the gripper system 27 of the first cylinder 13 in response to a rotation angle difference occurring between the cylinders 13, 14, a retracting mechanism for retracting the gripper system 27 of the second cylinder 14 is formed, and this retracting mechanism operates. The countersinking mechanism of the second cylinder 14 retracts its gripper system 27 into the interior of the cylinder in response to a rotational angle difference or a synchronous running disturbance occurring between the second cylinder 14 and a third cylinder (not shown in the drawings). In this case, the second cam follower 20 cooperates with a third securing cam of the third cylinder (likewise not shown in the drawing).

That in the FIG. 3 illustrated embodiment differs from the in FIG. 2 shown only by the use of a slide switch 33 or plunger which comes into operative connection with a wedge surface 34 for actuating the curve support 10.

LIST OF REFERENCE NUMBERS

1

gripper shaft

2

roller lever

3

follower

4

grab

5

Gripper pad

6

takeaway

7

cam

8th

Gripper pad spring

9

Claw spring

10

corner support

11

press

12

bow

13

first cylinder

14

second cylinder

15

first engine

16

second engine

17

first safety curve

18

second safety curve

19

first turn follower

20

second turn follower

21

trough

22

leading edge

23

trailing edge

24

Roller lever spring

25

Reset spring

26

cylinder gap

27

gripper system

28

gripper housing

29

direction

30

swivel

31

machine frame

32

gear lever

33

switch slide

34

wedge surface

35

retraction mechanism

Claims (8)

1. Method of safely operating a printing press (11) wherein a first cylinder (13) is driven by a first motor (15) and a second cylinder (14) is driven by a second motor (16), the first cylinder (13) accepting sheets (12) from or transferring sheets (12) to the second cylinder (14) by means of a gripper system (27),
   characterized in
   that in case of a deviation from the synchronized running of the cylinders (13, 14) the gripper system (27) is at least partially retracted far enough into the first cylinder (13) to avoid a collision between the gripper system (27) and the second cylinder (14).
2. Printing press (11) for implementing the method according to Claim 1, comprising a first gripper (13) with a gripper system (27), a first motor (15) for driving the first cylinder (13), a second cylinder (14) and a second motor (16) for driving the second cylinder (14),
   characterized in
   that the first cylinder (13) includes a retraction mechanism (35) for compulsorily retracting the gripper system (27) into the first cylinder (13) when a deviation from the synchronized running of the cylinders (13, 14) occurs.
3. Printing press according to Claim 2,
   characterized in
   that the retracting mechanism (35) comprises a first switching device co-rotating with the first cylinder (13) and that a second switching device is associated with the second cylinder (14) to co-rotate with the latter so that the switching devices get into switching contact with each other when the deviation from the synchronous running occurs.
4. Printing press according to Claim 3,
   characterized in
   that the second switching device includes a first shoulder (22) and a second shoulder (23), which are arranged opposite each other in the direction of rotation and with play relative to the first switching device, which dips into the second switching device without contact in case of undisturbed synchronized running.
5. Printing press according to Claim 4,
   characterized in
   that the first switching device is a switching lever (32) that is arranged in such a way that as a result of a switching contact between the switching lever (32) and the first shoulder (22), the switching lever (32) is swivellable in the same direction of rotation as as a result of a switching contact between the switching lever and the second shoulder (23).
6. Printing press according to one of Claims 3 to 5,
   characterized in
   that the second switching device is a safety cam (18).
7. Printing press according to one of Claims 3 to 6,
   characterized in
   that the first switching device is arranged to operate a control cam (7) controlling the gripper system (27).
8. Printing press according to Claim 7,
   characterized in
   that in the case of undisturbed synchronized running, the control cam (7) is supported by a cam support (10) that is arranged in such a way that when the deviation from the synchronized running occurs, the first switching device hits the cam support (10) as a result of its switching contact with the second switching device, thus adjusting the cam support (10) in a way to cause the cam support (10) to release an adjustment of the control cam (7).

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