DE19945243A1 - Printing machine with adjustable blanket cylinders - Google Patents

Abstract

The invention relates to an offset printing machine with a first plate cylinder (10), a first blanket cylinder (12) which can be adjusted to the first plate cylinder (10), a counter pressure cylinder (14) forming a printing gap with the first blanket cylinder (12), and a wedge (7), by means of which the first blanket cylinder (12) can optionally be kept at a distance from the impression cylinder (14). The impression cylinder (14) can be designed as a second blanket cylinder, which is assigned to a second plate cylinder (16).

Description

The present invention relates to printing presses, in particular web-fed rotary Offset printing machines, according to the preamble of claim 1.

In the case of web printing presses, there is usually a need to start up the Unrolling a paper web and leading it through the printing machine. Here can be a relatively complicated process. When replacing one Printing plate in the printing press often breaks the web, resulting in downtimes and result in increased paper consumption.

Accordingly, it is an object of the present invention to provide a printing press the risk of tearing the material web when changing the on the plate cylinder arranged printing plates is significantly reduced.

This object is solved by the features of claims 1, 10 and 20.

Further features and advantages of the present invention result from the Subclaims.

The present invention describes an offset printing machine with a first Plate cylinder; a first connected to the first plate cylinder Blanket cylinder; an impression cylinder, which with the first Blanket cylinder forms a printing nip; a web of material, which through the Pressure gap can be moved; a primary generating a compressive force Pressure element, which in the activated state the first blanket cylinder and the Impression cylinder pushes against each other; and one between the first Blanket cylinder and the impression cylinder arranged wedge, which at activated primary pressure element an adjustment of the impression cylinder to the Blanket cylinder prevented. The wedge can be operated by an air cylinder and on the bearing housing of the first blanket cylinder and the impression cylinder  Act. In the primary printing element, which the first blanket cylinder and the Counter-pressure cylinder pushes against each other, it can for example be a working Act air cylinder, which on the corresponding bearing housing and linkage Cylinder works. Such a device is e.g. B. described in US 5,301,609. The Impression cylinder can also be designed as a second blanket cylinder, and the Printing press can have a second plate cylinder. By means of the Air cylinders can move the first and second plate cylinders towards each other and thereby the cylinders arranged between them are placed against each other.

The present invention advantageously provides that the first Blanket cylinder and the impression cylinder with the help of the inserted wedge can be turned off from each other while the first plate cylinder and the first Keep blanket cylinders in line. Accordingly, the first The plate cylinder was changed when the blanket cylinder was turned on without the material web in the between the first blanket cylinder and the pressure gap formed is clamped. This allows one increased paper consumption can be prevented because of the risk of tearing the material web is reduced.

The present invention is explained in more detail below with reference to the drawing.

Fig. 1 shows a side view of the printing machine according to the present invention.

Fig. 1 shows a printing press 1 with a first plate cylinder 10, a first blanket cylinder 12, a second blanket cylinder and an impression cylinder 14, and a second plate cylinder 16. Printing plates can be applied to the first plate cylinder 10 and the second plate cylinder 16 , and rubber blankets can be applied to the blanket cylinders 12 and 14 . A web 9 passes through a pressure gap formed between the two blanket cylinders 12 and 14 .

The first plate cylinder 10 is rotatably attached at one end 10 a via a first bearing 210 in a first plate cylinder bearing housing 110 . The first blanket cylinder 12 , the second blanket cylinder or impression cylinder 14 and the second plate cylinder 16 are also fastened with their ends 12 a, 14 a and 16 a via bearings 212 , 214 and 216 in bearing housings 112 , 114 and 116 .

The first blanket cylinder bearing housing 112 is fixed to a frame of the printing press 1 . The bearing housings 110 , 114 and 116 , on the other hand, are arranged so as to be pivotable or translationally movable with respect to the frame, so that the bearing housings 110 , 114 and 116 can be moved up and down, as shown in FIG. 1. A primary pressure element 3 , preferably a hydraulic or pneumatic cylinder, acts on the first plate cylinder bearing housing 110 and the second plate cylinder bearing housing 116 , e.g. B. via lever or linkage shown schematically in Fig. 1 as lines 13 . During the printing operation, the bearing housing 110 is urged downward from the working air cylinder 3 against the stationary bearing housing 112 and the bearing housings 114 and 116 upwards against the stationary bearing housing 112 , so that all cylinders 10 , 12 , 14 and 16 with at least one of the cylinders 10 , 12 , 14 , 16 are in pressure contact and a pressure gap is formed between the two blanket cylinders 12 , 14 through which the web 9 can be passed.

When the printing machine 1 is at a standstill, the pressure transmitted to the two plate cylinders 10 and 16 via the linkage through the primary pressure element 3 can be released or vice versa, so that the first plate cylinder bearing housing 110 is turned off by the first, stationary blanket cylinder bearing housing 112 , and that second blanket cylinder bearing housing 114 z. B. comes to rest on a stop 5 . In this case, the second plate cylinder bearing housing 116 is preferably likewise set down from the second blanket cylinder bearing housing and lies on a further stop (not shown).

During a plate change, the primary pressure element 3 is pressurized, which is transmitted via the linkages 13 and the bearing housings 110 and 116 to the first and second plate cylinders 10 , 16 . The prevailing pressure keeps the plate cylinder 10 in contact with the blanket cylinder 12 and the plate cylinder 16 in contact with the blanket cylinder 14 . However, before the cylinder 3 is pressurized, a wedge 7 is moved by a second, preferably hydraulically, electrically or pneumatically operated, compressed air cylinder 6 between the first blanket cylinder bearing housing 112 and the second blanket cylinder bearing housing 114 , so that the two bearing housings 112 and 114 are separated from each other when the pressure exerted by the primary pressure element 3 urges the blanket cylinder bearing housing 114 of the second plate cylinder 14 upwards. In this way, the printing plates on the first plate cylinder 10 and on the second plate cylinder 16 can be changed in a known manner by rotating the respective blanket cylinder, while the plate cylinders 10 , 16 are still in the printing position with the respective blanket cylinders 12 , 14 , the blanket cylinders 12 , 14 are however separated from each other due to the wedge 7 located between them.

Of course, the wedge according to the present invention can be of various shapes and also be slidable by hand; however, it preferably has at least one an angled surface. The used in this application The term "impression cylinder" also includes a second blanket cylinder.  

LIST OF REFERENCES

1

Printing press

3rd

Pressure element

5

attack

6

additional compressed air cylinder

7

wedge

9

train

10th

first plate cylinder

10th

a cylinder end

12th

first blanket cylinder

12th

a cylinder end

13

management

14

second blanket cylinder / impression cylinder

14

a cylinder end

16

second plate cylinder

16

a cylinder end

110

first plate cylinder bearing housing

112

first blanket cylinder bearing housing

114

second blanket cylinder bearing housing

116

second plate cylinder bearing housing

210

camp

212

camp

214

camp

216

camp

Claims (11)

1. offset printing machine, in particular web-fed offset printing machine, with a first plate cylinder ( 10 ); a first blanket cylinder ( 12 ) which can be set on the first plate cylinder ( 10 ), a back-pressure cylinder ( 14 ) which can be set on the first blanket cylinder ( 12 ) to form a pressure gap, and one which acts on the first plate cylinder ( 10 ) and the back-pressure cylinder ( 14 ) Activatable pressure element ( 3 ) with which the first plate cylinder ( 10 ) and the impression cylinder ( 14 ) can be acted upon by a compressive force to move the cylinders towards one another, characterized by a for generating a distance between the first blanket cylinder ( 12 ) and the impression cylinder ( 14 ) wedge ( 7 ) acting during a pressure plate change. 2. Printing machine according to claim 1, characterized in that the first blanket cylinder ( 12 ) with one end ( 12 a) in a first blanket cylinder bearing housing ( 112 ) and the impression cylinder ( 14 ) with one end ( 14 a) in an impression cylinder- Bearing housing ( 114 ) is mounted, and that the wedge ( 7 ) between the first blanket cylinder bearing housing ( 112 ) and the impression cylinder bearing housing ( 114 ) is movable in such a way that the first blanket cylinder ( 12 ) and the impression cylinder ( 14 ) be kept at a distance from each other when the pressure element ( 3 ) urges the cylinders ( 12 and 14 ) towards each other. 3. Printing machine according to one of the preceding claims, characterized in that the wedge ( 7 ) is supported directly on the bearing housing ( 112 , 114 ) of the first blanket cylinder ( 12 ) and the impression cylinder ( 14 ). 4. Printing machine according to one of the preceding claims, characterized in that the wedge ( 7 ) is movable by an actuating device ( 6 ). 5. Printing machine according to claim 4, characterized in that the actuating device ( 6 ) is a pneumatic cylinder or a hydraulic cylinder. 6. Printing machine according to one of the preceding claims, characterized in that the first plate cylinder ( 10 ) with a first end ( 10 a) is mounted in a plate cylinder bearing housing ( 110 ) of the first plate cylinder ( 10 ), and that the primary printing element ( 3 ) acts on the plate cylinder bearing housing ( 110 ) of the first plate cylinder ( 10 ). 7. Printing machine according to one of the preceding claims, characterized in that the first plate cylinder ( 10 ) and the impression cylinder ( 14 ) are movable and the first blanket cylinder ( 12 ) are arranged stationary with respect to the frame of the printing press. 8. Printing machine according to one of the preceding claims, characterized in that the impression cylinder ( 14 ) is designed as a second blanket cylinder, on which a second plate cylinder ( 16 ) can be set. 9. Printing machine according to claim 8, characterized in that the primary printing element ( 3 ) acts between the first plate cylinder ( 10 ) and the second plate cylinder ( 16 ) in such a way that the first plate cylinder ( 10 ) and the second plate cylinder ( 16 ) can be moved towards each other by a pressure force generated by the pressure element ( 3 ). 10. Printing machine according to claim 9, characterized in that the second plate cylinder ( 16 ) with one end ( 16 a) is mounted in a plate cylinder bearing housing ( 116 ) which is movable relative to the frame of the printing machine in the direction of the second blanket cylinder. 11. Printing machine according to one of the preceding claims, characterized in that the primary printing element ( 3 ) is a pneumatic cylinder or a hydraulic cylinder.