Printing – Print plate feeding or delivering
Patent
1994-05-12
1996-03-05
Bennett, Christopher A.
Printing
Print plate feeding or delivering
1014151, B41F 2100
Patent
active
054958059
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
FIELD OF THE INVENTION
The invention relates to a device, in the form of a magazine, for supplying printing plates to a plate cylinder of a printing press, in particular for the automatic or semi-automatic changing of printing plates, with a plate-supplying apparatus.
A device of the initially mentioned kind is known from European patent application 0 435 410. The purpose of said device is to automate the changing of printing plates. The magazine holds old, used plates. For removal, the used printing plate is released from the plate cylinder at one end and is then--through appropriate rotation of the plate cylinder--partially inserted into the magazine. Subsequently, the other end of the printing plate is released by the tensioning device of the plate cylinder and the entire printing plate is introduced into the magazine with a plate-removing apparatus. Subsequently, a new printing plate to be used is taken from the magazine by means of the plate-supplying apparatus. First, one end of the printing plate is inserted into the corresponding clamping device of the plate cylinder, where it is clamped, and then--through rotation of the plate cylinder--the printing plate is removed completely from the magazine and is drawn around the outer cylindrical surface of the plate cylinder. Then, the other end of the printing plate is clamped and the plate is tensioned in the circumferential direction. The supplying of printing plates may be disrupted if, when a new printing plate is removed, at least one other of the new printing plates held in a pile in the magazine unintentionally changes its position.
SUMMARY OF THE INVENTION
The object of the invention is to create a device of the initially mentioned kind, the device permitting the operationally reliable supplying of printing plates while being of simple construction and small design.
The object of the invention is achieved in that the plate-supplying apparatus comprises a plurality of distributed, consecutively activatable (second) holding means for the printing plate.
In order to supply a new printing plate to be used, the printing plate is taken from the cassette of the magazine, supplied to the plate cylinder and clamped thereon. This operation takes place fully automatically or, alternatively, semi-automatically using the plate-supplying apparatus, with the non-simultaneous, but preferably consecutive activation of the second holding means over the length of the yet to be used printing plate having the advantage that the printing plate to be used can be lifted perfectly from the pile of new printing plates in the cassette, without--thanks to the flatness of the positioning--any further printing plate being lifted or slid out as a result of the formation of a vacuum. Preferably, the second holding means are in the form of activatable second suction elements.
It is advantageous if the second holding means are disposed on a second carriage, said carriage being movable along a second guide. Further disposed inside the magazine is a sensor which monitors the printing plate to be used, particularly the rear edge thereof, for correct supplying to the plate cylinder.
During the plate-supplying operation, the second holding means associated with the front edge of the new printing plate release the printing plate while it is more or less in the clamping position or hold it so loosely that the printing plate is displaceably held before the printing-plate front edge is clamped on the plate cylinder. The purpose of this is so that the printing plate can be better aligned during clamping. After the front edge has been clamped, tile plate cylinder rotates and pulls the new printing plate completely out of the cassette of the magazine. Both for the alignment of the printing plate and also for its removal from the cassette, the suction elements serving as the holding means may, for example by means of a bypass, be provided with such a weak vacuum that the printing plate slides on the suction elements.
As the angled printing-plate rear edge appr
REFERENCES:
patent: 5259314 (1993-11-01), Sugiyama
Beisel Hermann
Blaser Peter T.
Hauck Dieter
Hutzenlaub Rudolf
Ja/ ger Helmut
Bennett Christopher A.
Greenberg Laurence A.
Heidelberger Druckmaschinen AG
Lerner Herbert L.
LandOfFree
Device for supplying printing plates to a printing machine does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Device for supplying printing plates to a printing machine, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Device for supplying printing plates to a printing machine will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1406164