DE29714079U1 - Device for developing cylindrical surfaces - Google Patents

Description

Device for developing cylindrical surfaces

The invention relates to a device for developing cylindrical surfaces in printing machines with at least one integrated device for writing/imaging active surfaces of a printing form cylinder.

When writing/imaging using a special device integrated into a printing machine, the active surfaces of the printing form cylinder usually consist of an ink-repellent silicone layer and an ink-carrying image layer. If the active surfaces are written/imaged , the silicone layer is converted into particles at the required locations, thereby exposing the deeper ink-carrying layer. The silicone particles must be removed in a development step following the writing/imaging, whereby in the deeper zones/especially in the edge areas these silicone particles adhere so partially that their removal is problematic.

According to DE 19600846 Cl, a device for removing the silicone particles that are created during direct writing/image making is known. The device has a soft rubber strip that extends across the width of the printing form. In the direction of rotation ''·> of the printing form cylinder, a device for sucking out dissolved silicone particles is provided behind the rubber strip, followed by a roller with an adhesive surface. Means are also provided for moistening and for traversing the rubber strip.

The device has the disadvantage that due to the working elements rubber strip/suction device and adhesive roller arranged one behind the other in the direction of rotation of the printing form cylinder/extending across the width of the printing form cylinder, a large installation space is required and the accessibility to the printing form cylinder is restricted

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Another disadvantage is that this device only reliably removes the silicone particles that have only been dissolved in the edge areas of the deeper surfaces, which run in the circumferential direction or are located at the front in the axial direction and in the direction of rotation of the printing form cylinder, so that additional options must be provided to ensure that the dissolved silicone particles in the edge areas are also removed, which are located at the back in the axial direction and in the direction of rotation of the printing cylinder.

The object of the invention is to create a device for developing cylindrical surfaces/ which requires little installation space/ can be implemented using simple means and increases the efficiency of the printing machine.

According to the invention, the object is achieved by the protection claims.

The solution according to the invention ensures that the silicone particles that are created during direct imaging/labeling are immediately removed from the printing form cylinder after they are created, so that there is no danger of them getting into the printing machine. The working element of the developing device only ever processes the area of the printing form cylinder that has just been imaged/labeled.

The invention will be explained in more detail below using an embodiment.

In the drawings show

Fig. 1 shows a perspective view of a device according to the invention on a printing form cylinder/

Fig. 2 the device according to Fig. 1 in a schematic representation in side view

Figure 1 shows a printing form cylinder 1/ whose active surfaces are written/imaged by a device 14, as well as a device 2 for developing these active surfaces. When developing the active surfaces, the silicone particles that arise during writing/image creation are removed. The device 2 for developing is designed as a functional unit and consists of a frame 6/ which is mounted in the machine frame, for example by sliding surfaces 7 provided on the sides of the frame walls 8, and can be moved into a working position on the printing form cylinder 1 or away from it into a parking position using adjusting elements (not shown).

The device 2 has a brush roller 3 that is driven in rotation and is arranged so that it can be displaced in the axial direction. The brush roller 3 is mounted in a carriage 9, which is axially displaced, for example, by a screw gear. For this purpose, a threaded nut 10 is arranged in the carriage 9 in a rotationally fixed manner, into which a threaded spindle 11 engages, which is mounted in the frame walls 8 and is driven by means not shown. The brush roller 3 is driven by a splined shaft 12, which is also mounted in the frame walls 8, so that the brush roller 3 rotates in the opposite direction to the printing form cylinder 1. Below the brush roller 3, a doctor blade 5 is provided that extends at least over the width of the brush roller and is flush with the walls of the carriage 9 at the sides. The doctor blade 5 is connected in the lower area to a suction device 4/ which is arranged fixed to the frame in the carriage 9 and is connected to a vacuum shaft (not shown).

-A-

A laser head 14.1 is provided as a device 14 for writing/images the active surfaces of the printing form cylinder 1, for example, which is guided along the printing form cylinder 1 in an axial direction within a working cycle, with the printing form cylinder 1 itself rotating, for example, in the direction of rotation 15. In the embodiment in Fig. 1, the active surfaces of the printing form cylinder 1 are written/imaged starting from the left. Accordingly, the carriage 9 with the brush roller 3 is positioned in this area and is positioned against the printing form cylinder 1 by adjusting means acting on the frame 6 so that the brush roller 3 is in active connection with the active surfaces of the printing form cylinder 1, with the doctor blade 5 being adjusted so that it is not in contact with the printing form cylinder 1. The brush roller 3 is driven in the direction of rotation 16 via the splined shaft 12 and means not shown, while the carriage 9 - and thus the brush roller 3 - is moved in the working direction 13 by the combination of threaded nut 10/threaded spindle 11 synchronously with the laser head 14.1/ controlled by means not shown.

The silicone particles that are created when the active surfaces of the printing form cylinder 1 are imaged/written on are removed from the active surfaces of the printing form cylinder 1 by the counter-rotating rotations of the printing form cylinder 1 and the brush roller 3 immediately after they are created and/ guided by the doctor blade 5/ fed to the suction device 4 and sucked away by it. After the imaged/written on and the subsequent development of the active surfaces/ the carriage 9 with the brush roller 3 has moved once in the axial direction along the printing form cylinder 1/ the frame 6 is set down by adjusting means not shown from the printing form cylinder 1 and the carriage 9 is returned to its parking position.

List of reference symbols used

1 printing form cylinder

2 Development facility

3 Brush roller

4 Extraction device

5 Squeegees

6 Frame

7 Sliding surface

8 Frame wall

9 sledges

10 Threaded nut

11 Threaded spindle

12 Splined shaft

13 Working direction

14 Device for writing/imaging 14.1 Laser head

15 Direction of rotation

16 Direction of rotation

Claims (3)

Protection claims 1. Device for developing cylindrical surfaces in printing machines - with at least one integrated device (14) for writing/image-producing active surfaces of a printing form cylinder (I)/ - the device (2) is designed as a functional unit that can be moved either into a working position on the printing form cylinder (1) or into a parking position remote from it/ - the device (2) has a carriage (9) that can be moved synchronously with the device (14) for writing/image-making in the working direction (13) running axially of the printing form cylinder (1), - in the carriage (9) there is a positively driven brush roller (3) which in the working position is in operative connection with the active surfaces of the printing form cylinder (1) and - a suction device (4) associated with the brush roller (3) is provided. 2. Device according to claim 1/ - with a doctor blade (5) arranged in the carriage (9)/ associated with the brush roller (3)/ which in the working position does not touch the active surfaces of the printing form cylinder (1). 3. Device according to claim 1/ - with a frame (6) extending at least over the width of the printing form cylinder (1).