Abstract: An apparatus and method for feeding a stream of underlap-imbricated sheet-like printing substrates to printing machine, the apparatus comprising a conveying table for conveying the stream in a conveying direction toward the printing, a source of compressed air, and at least one blowing device coupled to the source of compressed air, the blowing device being disposed in a region of the conveying table adjacent to printing machine, and including at least one opening disposed to direct compressed air beneath the imbricated stream in a direction opposite to the conveying direction.

Abstract: A method for automatically feeding a printing plate in proper registry to a plate cylinder in a printing machine is disclosed. Pursuant to the disclosed method, a printing plate is advanced by a plate conveyor towards a clamping rail on the plate cylinder. After the leading edge is inserted into the clamping rail, the in-register condition of the leading edge of the printing plate is independently sensed at two sensing sites. If the leading edge of the printing plate is in register at only one site, the printing plate is released from the plate conveyor for a period of time to permit the printing plate to align itself. The printing plate is then held again by the plate conveyor and the advancement of the plate is resumed. This process is repeated until the independent sensors both indicate that registry has been achieved.

Abstract: A magazine for the automated changing of printing plates of a sheet-fed offset printing machine. The magazine includes a guiding apparatus which can be put into place on the plate cylinder for purposes of conveying used printing plates out of the plate cylinder and for feeding new printing plates to the cylinder. The guiding apparatus may be formed by a sheet-metal profile. Provision is made of further guiding surfaces and a holder so that the used printing plate may be locked by the holder. An operator then only need pull the plate a short distance out of the gripping region of a leading edge clamping rail. Stops are provided for a printing plate so that the new printing plate can be deposited on the stops. By virtue of putting the guiding apparatus into place, the new printing plate is shifted toward the plate cylinder and can be fed into the front clamping rail by the operator.

Abstract: A method and an apparatus for controlling an automated printing plate change process in a sheet-fed offset printing machine, in which a used printing plate is removed from the gripping portion of a clamping rail allocated to the leading edge of the plate cylinder and thereupon a new printing plate is guided into the opened gripping portion. Position sensors are used to determine, first, whether the front end of the used printing plate, and subsequently, whether the front end of the new printing plate, is in register in the leading edge clamping rail. Such information is used to control the plate change process. During the plate change process, the sensors are interrogated to determine whether the used plate has been removed from the plate cylinder, and whether the new printing plate is properly loaded.

Abstract: A mechanism is provided for adjusting printing plates on plate cylinders in sheet-fed offset printing machines. After the leading and trailing edges of the printing plate have been clamped onto the plate cylinder by clamping bars or attachment devices, the adjusting mechanism is utilized to provide circumferential and axial translation of the printing plate relative to the plate cylinder for registration correction. The adjusting mechanism selectively translates only those attachment devices clamping the edge of the printing plate which require this correction. In the preferred embodiment, the adjusting mechanism is a hand tool with a shank having a handle at one end and a cam at the other. Upon placing the tool at predetermined locations on the plate cylinder and turning the handle, the cam acts on the engagement surfaces of the attachment devices which are pivotable about their longitudinal axis causing circumferential translation of the printing plate.

Abstract: A clamping device for attachment of a printing plate having registry defining notches in the leading edge thereof in proper registry on the plate cylinder of a sheet-fed printing machine is provided. The clamping device includes a clamping rail disposed in an axis-parallel recess in the plate cylinder and has a closable plate receiving gap therein for fastening the leading edge of the printing plate to the clamping rail. A plurality of adjustable stops are disposed in the plate receiving gap of the clamping rail for abutting the corresponding registry defining notches in the leading edge of the printing plate for locating the printing plate on the cylinder in proper registry.

Abstract: A gripper finger for a sheet gripper system for a printing press, to which gripper unwanted paper dust, dirt, debris, or the like cannot stick, the profiled retaining surface of the finger has in its front part a single bead-like protuberance which contacts the sheet, has a bead radius (R) of from 0.4 to 1.0 mm, extends parallel to the front edge of the sheet and is coated with a hard substance.