Cleaning device for printing unit cylinders, in particular for rubber blanket cylinder to offset printing machines.

摘要

911,294. Printing machines; set-off preventing. ALLERS ETABLISSEMENT A.S., CARL. Dec. 2, 1958 [May 27, 1958], No. 1.6952/58. Class 100 (2). A rotary offset printing machine includes a scraper to clean the surface of the offset cylinder blanket as it rotates, the scraper comprising flexible elements which are secured at their ends so that when the elements are pressed against the blanket they conform between their ends to the peripheral form of the blanket to exert an extended scraping action thereon. The scraper elements consist of wires 9 stretched obliquely between the two side edges of an arcuate, slightly resilient holder 6 which is mounted by means of arms 7 on a shaft 8 and is parallel to the axis of the offset cylinder 1. The shaft 8 is rotated by means of a lever 11 and spring 13 so as to position the scraper with the wires 9 either out of or in contact with the blanket on the cylinder 1. In the latter position the wires scrape off stale ink and other foreign matter as the cylinder 1 rotates. The interior of the holder 6 is in communication with a source of suction and the matter removed by the wires is thereby sucked away from the holder, baffle plates 10 localizing the sucking action to the operative zone of the scraper wires. The scraper may extend the full width of the offset blanket or only part of the width and in either case may be reciprocated in a direction parallel to the axis of the cylinder. The wires 9 may be kept in constant or intermittent contact with the blanket. In a modification, the wires 9 are replaced by a resilient metal sheet having strips stamped out of the middle portion thereof, the marginal portions of the sheet being clamped in a holder.