GB1055369A - A litho printing machine, particularly an offset printing machine - Google Patents

Abstract

1,055,369. Printing machines. ROTAPRINT A.G. May 6, 1965 [May 8, 1964], No. 19247/65. Heading B6C. [Also in Division F2] The drive shaft of a lithographic machine can be rotated either by a hand-crank 2 or by a motor-driven pulley 16, the coupling between the pulley 16 and the shaft 5 comprising a helical spring 15 connected at one end 16a to the pulley 16 and at the other end 14a to an external sleeve 14, the spring 15 surrounding a clutch member 6 keyed to the shaft 5. A roller 13 on a lever 7 can be engaged with the sleeve 14 adjacent to the end 14a so as to brake the sleeve and cause the spring 15 to twist itself tightly on the member 6, thus coupling the shaft 5 to the pulley 16. The handle 2 is urged axially leftwards by a spring 3, such movement being limited by the engagement of a follower part 11 on the lever 7 with a concentric track 9 on the hub 1 of the handle 2. In this position a clutch part 4 on the hub 1 engages a clutch part of the member 6, and the roller 13 is disengaged from the sleeve 14, so that the shaft 5 can be rotated by the handle 2. To employ the power drive, the handle when hanging vertically downwards is moved axially to the right so as to disengage the clutch parts 4, 6. During such movement, the follower part 11 first engages an eccentric track 12 on the hub, which is a neutral position wherein neither drive is engaged, and then drops into a recess 12a allowing the roller 13 to engage the sleeve 14 so as to couple the power drive to the shaft 5. If the handle 2 is now rotated, the follower 11 slips out of the recess 12a and on to the eccentric track 12 to uncouple the power drive. Upon further rotation of the handle 2, the eccentric track 12 moves the follower 11 radially outward until it slips back on to the track 9 under the action of spring 3.