Improvements in Means for Varying the Throw or Extent of Lateral Reciprocating Movement of a Web Looping Roller so as to cause it to take up and give off more or less Web in a given interval of time, especially applicable to Stationary-bed Web-printing Presses to enable them to Print Different Lengths of Sheets.

摘要

8521. Thompson, W. P., [Dowell, A. E.]. April 25. Feeding-apparatus for webs; cylinder machines with plane printing-surfaces.-Relates to apparatus for feeding and manipulating webs in machines in which the web is fed in and out continuously, but has periods of rest in the machine, more particularly applicable for operating the looping- rollers of a Cox " Duplex " printing-press. The object is to adjust the extent of the movement of the loopers so that various lengths of sheet may be printed by varying the speed of the feed-rollers. Fig. 1 shows part of a press, of which K are the feeding-in rollers, O are the feeding-out rollers, and l, l1 are the looping-rollers on the frame L. The lever A operated by the looper cam D has an adjustable fulcrum a, which engages and operates a lever B, operating the frame L through a link b. The pivot of the lever B is nearer to the frame L than that of the lever A. A screw a2 or other means may be used for adjusting the fulcrum a. In modifications, (1) the lever B is pivoted on the other side of the frame L, and (2) the pivot or fulcrum at the left-hand end of the lever A is adjustable on the framing and the lever B is omitted.