公开(公告)号：CA1168179A

公开(公告)日：1984-05-29

申请号：CA374685

申请日：1981-04-03

Applicant: IBM

Inventor： JAGODZINSKI PETER F ,  FIELD THOMAS R ,  PATRICK CARL D

IPC: B65H23/06 ,  B41J32/00 ,  B41J33/00 ,  B41J33/16 ,  B41J33/52 ,  B65H75/02 ,  B41J35/28 ,  B41J32/02

Abstract: ANTI-REVERSAL BACKCHECK FOR PRINTER RIBBON CARTRIDGE TAKEUP SPOOL In a typewriter ribbon cartridge, it is necessary to maintain tension on the span of ribbon extending outside the cartridge to prevent tangling and to insure high print quality during machine operation. One technique for insuring that adequate tension is maintained is disclosed herein as an anti-backup back check device. Connected to the takeup spool of the ribbon cartridge is a disc member supporting thereon a pair of thin flexible resilient arms with outwardly oriented pointed ends. These ends formed in the shape of points engage ratchet teeth formed around the interior surface of a cylinder. The cylinder is formed as a part of the ribbon cartridge and, thus, is permanently positioned and fixed with respect to it. As the takeup spool disc and arms are rotated by the ribbon feed mechanism, the arms will flex and permit a rotation of the disc and takeup spool with a minimal drag force. Upon reversal, the points on the ends of the arms engage the ratchet teeth and the arms become compression columns resisting the rotation of the disc and spool. The center of the disc and the takeup spool are free floating within reasonable physical constraints. The teeth of the arms are positioned such that they are one-half tooth pitch out of phase to insure that one tooth is always in engagement with a tip of one of the two pawls.

公开(公告)号：AU537114B2

公开(公告)日：1984-06-07

申请号：AU7133781

申请日：1981-06-04

Applicant: IBM

Inventor： FIELD THOMAS R ,  JAGODZINSKI PETER F ,  PATRICK CARL D

IPC: B65H23/06 ,  B41J32/00 ,  B41J33/00 ,  B41J33/16 ,  B41J33/52 ,  B65H75/02

Abstract: Connected to the take-up spool (26) of the ribbon cartridge (10) is a disc member (28) supporting a pair of flexible arms (32) with outwardly oriented pointed ends (34). Ends (34) engage ratchet teeth (44) formed on the internal surface of a cylinder (42) forming part of, or attached to, the ribbon cartridge (10). As disc (28) and arms (32) are rotated by the ribbon feed mechanism, arms (32) will flex and permit a rotation of disc (28) and take-up spool (26) with a minimal drag force. Upon reversal, the ends (34) of arms (32) engage ratchet teeth (44) and arms (32) become compression columns resisting the rotation of disc (28) and spool (26). Ends (34) of arms (32) are positioned such that they are one-half tooth out of phase to ensure that one tooth is always in engagement with the end (34) of one of the two arms (32).