The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 16, 1990
Filed:
Jun. 27, 1988
Walter D'Heureuse, Ladenburg, DE;
Hans-Jurgen Kusch, Neckargemund, DE;
Gerhard Heppenstiel, Bammental, DE;
Rudi Stellberger, Kronau, DE;
Heidelberger Druckmaschinen AG, Heidelberg, DE;
Abstract
A dampening unit for an offset printing machine, includes a roller pair consisting of a metering roller, and a dampening form roller for applying dampening medium to a plate cylinder of the printing machine, the metering roller and the form roller being in mutually pressing engagement at a first contact zone along respective axially parallel lines on respective casings of the roller pair, a gear drive for driving the roller pair with circumferential speeds of the metering roller and the form roller substantially in a downward direction in vicinity of the contact zone, and means defining a storage space for dampening medium located above the contact zone and including surfaces of the casings of the roller pair and sealing elements located at respective ends of the roller pair, only the metering roller of the roller pair being driven by a gear meshing with a drive gear of the gear drive, the form roller being in driven engagement via friction contact at the first contact zone in a first position of the form roller wherein the form roller is lifted away from the plate cylinder, and being in driven engagement via friction contact both at the first contact zone and at a second contact zone between the form roller and the plate cylinder in a second position of the form roller wherein the form roller is in engagement with the plate cylinder, the metering roller being drivable at a circumferential speed increased to such an extent over that of the plate cylinder to compensate for braking moments applied to the form roller so that the form roller rotates in the second position thereof with a circumferential speed slower by an order of magnitude of 0.5% to 2% than the circumferential speed of the plate cylinder.