EP0432660A2 - Device for exchanging a printing plate - Google Patents

Abstract

In a method and a device for carrying out the method for automatically changing a printing plate on a plate cylinder of a rotational printing machine, a printing plate changing device with transport rollers and storage chambers is provided, in which device the printing plate is placed.

Description

Method and device for automatically changing a printing plate

The invention relates to a method and a device for carrying out the method for automatically changing a printing plate on a plate cylinder of a rotary printing press.

Through the EP note. 02 68 857 a semi-automatic device is known with which it is possible to attach a printing plate on the plate cylinder of a rotary printing press.

A disadvantage of the device according to EP application. 02 68 857 is that the pressure plate must be inserted into the clamping device by hand; In addition, the commands for placing the pressure plate, clamping and clamping must be entered manually on a control panel.

The invention has for its object to provide a method for changing a printing plate on a plate cylinder and a device for performing the method.

The object is achieved by the features of the characterizing part of claims 1 and 2.

The advantage of the method and the device according to the invention is in particular that for attaching the printing plates to the plate cylinder

Auxiliary staff can be used. Touching the personnel with the rotating parts of the machine is excluded. H. security is increased. Machine downtimes for changing the printing plates are reduced.

A position relevant to the plate on the plate cylinder becomes more precise. A waste of paper waste caused by lengthy registration correction is reduced.

Fig. 1

eine Seitenansicht der erfindungsgemäßen Druckplattenwechseleinrichtung im Schnitt,

Fig. 2

einen vergrößerten Ausschnitt aus der Darstellung der Seitenansicht des Transportbereiches der Druckplattenwechseleinrichtung,

Fig. 3

eine vergrößerte Seitenansicht der Klemmeinrichtung für ein Druckplattenende, "Druckplattenklemmstellung",

Fig. 4

eine vergrößerte Seitenansicht der Klemmeinrichtung für einen Druckplattenanfang, "Druckplattenzuführstellung",

Fig. 5

Steuereinrichtung und Steuerrechner,

Fig. 6

einen Ablaufplan.

An embodiment of the invention is shown in the drawings and is described below. Show it

Fig. 1

a side view of the printing plate changing device according to the invention in section,

Fig. 2

2 shows an enlarged detail from the representation of the side view of the transport area of the printing plate changing device,

Fig. 3

an enlarged side view of the clamping device for a printing plate end, "printing plate clamping position",

Fig. 4

an enlarged side view of the clamping device for a printing plate start, "printing plate feed position",

Fig. 5

Control device and control computer,

Fig. 6

a schedule.

A rotary printing press has several printing units 1 (z. B. 4), each u. a. a plate cylinder 3, a blanket cylinder 4 and an impression cylinder 6 included. These are stored in the usual way in side frames of the rotary printing press.

Since the various printing units 1 are almost identical to one another, the invention is only described with reference to a printing unit 1.

A printing plate changing device 9 is provided on an access side 8 to the cylinders 3, 4, 6 of the printing unit 1. The pressure plate changing device 9 is attached to a cover plate 11, which serves as a coupling. This is together with the printing plate changing device 9 by means of two rockers 17; 18, which are attached to the side frames of the printing towers 1, are arranged vertically pivotable in two end positions. The swivel radii are shown by dashed lines. For this purpose, an upper and lower Glleenk 14; are on a front and rear side of the cover plate 11; 16 provided, in each of which a first end of the rocker 17; 18 is pivotally mounted. A second end of the rocker 17, 18 is pivotally mounted on the side frames. The cover plate 11 as a coupling, the wings 17, 18 and the frame of the printing unit 1 as a web thus form a four-bar link.

At a lower end on both sides of the cover plate 11, a double-acting cylinder 19 is pivotally mounted. A piston rod 21 of the working cylinder 19 is articulated to a lever 22. The lever 22 rotatably supports in its first end mounted a parallel pressure roller 26 with a drive 23 arranged parallel to the axis of the plate cylinder 3. The pressure roller 26 can also be offset. The pressure roller 26 has a surface which is soft in relation to a pressure plate 27 (for example rubber; plastic). The lever 22 is pivotally mounted about an axis 30 of a drive roller 28 which is rotatably mounted in side supports (not shown) of the cover plate 11. The drive roller 28 is offset and has a drive (z. B. gear drive, electric motor, pneumatic motor, etc.).

In the exemplary embodiment, this is represented schematically by a chain wheel 31 with a drive chain 32.

The drive roller 28 and the pressure roller 26 can, however, also be in drive connection with one another, for. B. by a chain drive, wherein they should preferably have the same peripheral speeds.

The drive roller 28 is in drive contact with a further drive roller 29 (for example, gear drive) such that the drive rollers 28, 29 rotate in opposite directions, i. H. in a nip formed by the drive rollers 28, 29 they have a common transport direction. All transport rollers have a soft, elastic surface (e.g. rubber) which is at least softer than the pressure plates 27, 60 used, so that they cannot damage them.

A pressure roller 33 is arranged such that it can be brought into contact with the driven drive roller 29. For this is the Pressure roller 33 is rotatably supported in a first end of a two-armed lever 34.

The lever 34 is pivotally mounted almost centrally in the side supports of the cover plate 11 and has a bearing point 36 at a second end, in which one end of a piston rod 37 engages in an articulated manner. The piston rod 37 is part of a working cylinder 40 which is articulated to the cover plate 11.

The printing plate changing device 9 consists of an approximately printing plate-wide housing with two storage chambers 73, 74. When viewed in section, the housing has a slight curvature such that an upper part of the housing is aligned almost vertically and a lower part of the housing tangentially to a lower part of the plate cylinder 3 is aligned.

The housing is made in two parts and has a hinge 42 above the cover plate 11, by means of which an upper part of the housing can be folded down, whereby an upper part of the printing tower 1, in which an inking unit (not shown) of the printing press is provided in the usual way is accessible to an operator.

A front wall 43 of the housing extends shortly before the pressure roller 26 and has openings 44 in the area of the drive roller 28, through which surface areas of the stepped drive roller 28 protrude from below into the storage chamber 73. A rear wall 46 of the housing extends shortly before Pressure roller 33.

A wall 78 separates the storage chambers 73, 74 from one another and extends to just before the drive roller 29, where it ends in two guide plates 79, 81, which ensure that the pressure plate 27, 60 to be supplied or removed enters the correct nip.

Behind the pressure roller 33, a plurality of ejection fingers 45 are provided parallel to a wedge-shaped guide plate 76, which are arranged fixedly on an ejection finger shaft 47 which is pivotably mounted in the side supports of the cover plate 11. At a distance from the pivotable mounting of the ejection finger shaft 47, a piston rod 48 articulates on a lever 50 of the ejection finger shaft 47 to actuate it. The piston rod 48 is part of a working cylinder 49 which is articulated to the cover plate 11. The ejection fingers 45 can be pivoted by means of the piston rod 48 in such a way that their tips 68 dip into the periphery 62 of the plate cylinder 3 or lift off over the periphery 62.

The plate cylinder 3 has a plate clamping and tensioning device 53, 54 in a pit 52. The plate clamping device is e.g. B. known from DE-PS 36 26 936. This is characterized in particular by a conveniently arranged pivot pole of the clamping flap 55; 56 out. This has the effect that a pressure plate end 57 is not hindered by the clamping flap 55 when it is inserted into or removed from the plate clamping device 54.

The jig is e.g. known from DE-OS 36 04 071.

Upon rotation of the plate cylinder 3 from a pressure plate release position A clockwise (backward) and pressurization of the working cylinder 49, the tips 68 of the gripper fingers 45 pass through corresponding openings 64 in the clamping flap 55 into recesses 65 in the plate clamping and tensioning device 54 under the pressure plate end 57 and thus support a lifting of the pressure plate end 57 from a clamping support 63.

Provided actuating means for the plate clamping and tensioning device 53, 54 are supplied with working medium via a rotary entry on the plate cylinder journal. Of course, it is also possible to provide devices which, when the plate cylinder 3 is at a standstill, in a plate cylinder position A; B; C, supply it with working medium via its end face or lateral surface. The actuating means can be designed as hydraulic, pneumatic, mechanical or else electrical units.

In printing operation, the printing plate store 9 is in a position according to FIGS. 1 and 2. In this position, access to the cylinders 3, 4, 6 is closed by the cover plate 11; however, the pressure roller 26 and the gripper fingers 45 are pivoted away from the plate cylinder 3.

In a printing plate release or feed position A, B, the pressure roller 26 is set against the plate cylinder 3.

After the end of the current printing job, the plate cylinder 3 moves into the predetermined angular position A (printing plate release position) (FIG. 2). The clamping flap 55 is opened. A pressure plate end 57 springs outwards due to its elastic inherent tension until it strikes the guide plate 76 or is lifted off the clamping support 63 by the ejection fingers 45 by rotating the plate cylinder 3 into the pressure plate clamping position C.

A rotation of the plate cylinder 3 clockwise (backwards) now causes the pressure plate 27 to be pushed out into the storage chamber 74, the pressure roller 26 being driven counterclockwise with a preselectable torque. The torque allows the friction between plate 27; 60 and roll surface 26 do not exceed.

Here, the pressure plate end 57 comes into a gap between the drive roller 28 and the parked pressure roller 33. The pressure plate 27 is transported through the gap between the transport rollers 29, 33 into the storage chamber 74 until the plate cylinder 3 reaches the pressure plate feed position B and the clamping flap 55 to hold the printing plate start 58 opens. Almost simultaneously, the pressure roller 33 is set against the drive roller 29 by means of the working cylinder unit 37, 40. Activation of the drive 31, 32 now causes the pressure plate 27 to be removed from the contact area, ie the lower part of the pressure plate changing device 9, and to be fed to the storage chamber 74.

At the same time, the drive rollers 28, 29 transport a pressure plate 60 previously inserted into the storage chamber 73 into the application area until the pressure plate start 58 of the new pressure plate 60 abuts a stop 51 of the plate clamping and tensioning device 53. A position detector 59 for monitoring the installation of the pressure plate 27; 60 on the stop 51 gives a "good" signal to a control computer 66, whereupon the clamping flap 56 is closed. The start of the pressure plate 58 is clamped. The plate cylinder 3 is now rotated counterclockwise (forward) while the pressure roller 26 presses the pressure plate 60 against the plate cylinder 3. If the position detector 59 signals, however, that the pressure plate 60 is not in good contact with the stop 51 of the plate clamping device 54, a corresponding interference signal is generated.

When a plate cylinder position (printing plate clamping position) C (FIG. 3) is reached, in which the printing plate end 57 is pressed onto the clamping surface 63 by the pressure roller 26, the clamping flap 55 closes and clamps the printing plate end 57 firmly. Subsequent activation of the clamping elements clamps the pressure plate 60 on the plate cylinder 3.

The position C is subdivided into angular degrees only a little (e.g. 5 ° - 10 °) behind the pressure plate release position A, i.e. the plate cylinder 3 only has to be turned a little bit counterclockwise from the pressure plate release position A until it reaches position C ( Fig. 3) reached.

In position C, the pressure roller 26 has slightly bent the pressure plate end 57 around an edge 61 of the plate cylinder pit 52, so that the pressure plate end 57 comes to lie within the periphery 62 of the plate cylinder 3 on the clamping support 63 of the clamping device 54 before it is released from the clamping flap 55 is held.

The pressure roller 26 is then pivoted back into the printing press operating position in that the double-acting working cylinder 19 pressurizes the piston rod 21, and the pressure roller 26 swivels about the axis 30 of the drive roller 29 from the plate cylinder 3. The printing plate change has ended.

The control computer 66 is connected to a number of solenoid valves 67 which, when a command is given, change the pressure plate in the correct sequence depending on the positions of the plate cylinder 3 and in conjunction with suitable software and supply the actuating cylinders with working medium from a pressure source 72 (FIG. 4) .

The positions A, B, C of the plate cylinder 3 are determined by means of an angle encoder 71 and fed to the control computer 66 (FIG. 4).

All electrical drives (e.g. plate cylinder drive M; drive for the transport roller 33) are also controlled by means of the control computer 66. The software of the control computer works according to a flow chart (FIG. 6), so that all steps 101-137 be carried out automatically one after the other.

After actuation of a start trigger 101 (FIG. 6), security conditions of the rotary printing press are queried in a first step 102 (for example, is the cover plate 11 closed?). If all safety conditions are not met, an interference signal 103 is generated. If the safety conditions are met, a start-up warning signal is generated in a subsequent step 104.

After repeated activation of the start trigger 101 (triggered manually or also by the control computer 66), the plate cylinder 3 rotates in step 106 into the plate cylinder position A. When the plate cylinder position A is reached, the pressure roller 26 is set against the plate cylinder 3 in a step 107, on it the plate tension is switched off in step 108, the clamping flap 55 is opened in step 109, the ejection fingers 45 are pivoted into the periphery 62 of the plate cylinder 3 in step 111 and the transport roller 33 is pivoted away from the drive roller 29 in step 112.

In a subsequent step 113, the drive 23 is activated and the plate cylinder 3 is moved backwards into the plate cylinder position B. After a circumferential path (approx. 50 mm) has been covered, the ejection fingers 45 are pivoted out of the periphery 62 in a step 114. The plate cylinder 3 continues to rotate up to the plate cylinder position B (step 116). If the plate cylinder position B is reached, the drive 23 is turned off in a step 117. In step 118, the pressure roller 33 is attached to the drive roller 29 employed.

In step 119, the clamping flap 56 is opened. In the subsequent step 121, the pressure roller 26 is turned off somewhat by the plate cylinder 3 and only serves as a guide for the old and new printing plates 27, 60. Then the drives 31, 32 are activated in step 122 and the plate tension is released (step 123). The old printing plate 27 is now transported out of the clamping device 54 by means of the transport rollers 29, 33; at the same time, the new pressure plate 60 is transported from the storage chamber 73 to the clamping device 54.

In step 124, a position detection of the new printing plate 60 is queried. If the plate position is not correct, the pressure plate 60 continues to be advanced by means of the transport rollers 28, 29. If the pressure plate 60 is still not correctly positioned after repeated interrogation of the position detector 59, an interference signal 126 is generated. However, if the pressure plate 60 abuts the stop 51 correctly, the drive 31, 32 is turned off in step 127.

In steps 128, 129 the clamping flap 56 is closed and the pressure roller 26 is placed against the plate cylinder 3 under slight pressure.

In the subsequent step 131, the plate cylinder 3 is moved forward into the plate cylinder position A; At the same time, the drives 23, 31, 32 are activated. When the plate cylinder position A is reached, the drives 31, 32 are turned off in step 132.

In step 133, the plate cylinder position C is approached and then in step 134 the clamping flap 55 is closed, in step 135 the plate tension is applied and in step 136 the pressure roller 26 is removed and released. The printing plate change is finished; an end 137 signal is generated.

Parts list

1

 Printing unit

2nd

 -

3rd

 Plate cylinder

4th

 Blanket cylinder

5

 -

6

 Impression cylinder

7

 -

8th

 Access page

9

 Pressure plate changing device

10th

 -

11

 Cover plate

12

 -

13

 -

14

 Joint (upper)

15

 -

16

 Joint (lower)

17th

 Swingarm

18th

 Swingarm

19th

 Working cylinder

20th

 -

21

 Piston rod

22

 lever

23

 drive

24th

 -

25th

 -

26

 Pressure roller

27th

 printing plate

28

 Drive roller

29

 Drive roller

30th

axis

31

 Sprocket

32

 Drive chain

33

 Pressure roller

34

 lever

35

 -

36

 Depository

37

 Piston rod

38

 -

39

 -

40

 Working cylinder

41

 -

42

 hinge

43

 Front wall (9)

44

 Breakthroughs

45

 Ejection finger

46

 Rear wall (9)

47

 Ejection finger wave

48

 Piston rod

49

 Working cylinder

50

 lever

51

 attack

52

 Pit (3)

53

 Plate clamping and tensioning device

54

 Plate clamping and tensioning device

55

 Clamp flap

56

 Clamp flap

57

 Pressure plate end

58

 Printing plate start

59

 Location detectors

60

Pressure plate (new)

61

 Edge (52)

62

 Periphery (3)

63

 Clamping pad (54)

64

 Breakthroughs

65

 Recess (54)

66

 Tax calculator

67

 Solenoid valve

68

 Lace (45)

69

 -

70

 -

71

 Angle of rotation encoder

72

 Pressure source

73

 Storage chamber

74

 Storage chamber

75

 -

76

 Guide plate

77

 -

78

 wall

79

 Guide plate

80

 -

81

 Guide plate

101

 )

.

 )

.

 ) Follow-up steps of the schedule

.

 )

137

 )

A

 Pressure plate release position

B

 Printing plate feed position

C.

 Pressure plate clamping position

M

 Plate cylinder drive

Claims (14)

Method for automatically changing a printing plate (27) on a plate cylinder (3) of a rotary printing press, which u. a. Has means (53, 54) for clamping and tensioning the printing plate (27), characterized in that a printing plate (60) is placed in a storage chamber (73) of a printing plate changing device (9), that the plate cylinder (3) is in a printing plate release position ( A) is rotated, that a clamping flap (55) for detecting a printing plate end (57) is opened, that the plate cylinder (3) is rotated backwards into a printing plate feed position (3), that a clamping flap (55) for detecting the beginning of the printing plate (58) is opened that the pressure plate (27) by means of a number of transport rollers (28, 33) is fed to a storage chamber (74), that at the same time a stored pressure plate (60) by means of a number of transport rollers (28, 29) a clamping device (53) of the plate cylinder (3) is supplied, that a clamping flap (56) of the clamping device (53) is closed, that the plate cylinder (3) is moved forward into a pressure plate clamping position (C) d that the clamping flap (55) is closed. A method according to claim 1, characterized in that when the pressure plate (27; 60) rests against a stop (51) of the clamping device (53, 54), a "good" signal is generated by a system detection (59), which then causes the clamping flap (56) is closed. Device for automatically changing a printing plate (27) on a plate cylinder (3) of a rotary printing press, which u. a. Has means (53, 54) for clamping and tensioning the printing plate (27), characterized in that the printing plate changing device (9) has at least two storage chambers (73, 74), that the printing plate changing device (9) has a number of transport rollers (28, 29, 33). Device according to claim 3, characterized in that at least one transport roller 28; 29) has a drive (31, 32). Device according to claim 4, characterized in that the pressure roller (33) is arranged so as to be adjustable against the drive roller (29). Device according to claims 4 and 5, characterized in that computer-controlled adjusting means (37, 40, 67) are provided for generating a positioning movement of the pressure roller (33). Device according to claims 5 to 7, characterized in that a pivotable pressure roller (26) is provided, that the pressure roller (26) has a drive (23). Device according to claim 7, characterized in that adjusting means (19, 21, 67) are provided for producing a pivoting movement of the pressure roller (26). Device according to claim 4, characterized in that ejection fingers (45) are provided. Device according to claims 4 and 9, characterized in that the ejection fingers (45) are fastened on a pivotably mounted ejection finger shaft (47). Device according to claims 4, 9 and 10, characterized in that the ejection fingers (45) have tips (68), that the tips (68) are arranged so as to be pivotable into the periphery (62) of the plate cylinder (3). Device according to claims 4, 9 to 11, characterized in that openings (64) are provided in the clamping flap (55) of the plate clamping and tensioning device (54) and recesses (65) are provided in the plate clamping and tensioning device (54). Device according to claims 4, 9 to 12, characterized in that adjusting means (48, 49, 67) are provided for producing a swiveling movement of the ejection fingers (45). Device according to claim 4, characterized in that the pressure plate store (9) is constructed in two parts and has a joint (42) connecting the two parts.

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