Ribbon drive system for a thermal demand printer

摘要

A demand printer for printing on media includes a ribbon take-up spindle for accumulating spent printing ribbon and facilitating removal of the spent ribbon from the spindle. The spindle has a surface with a protrusion bore formed therethrough. At least one protruding segment extends through the protrusion bore. The protruding segment controllably projects away from the spindle surface for maintaining a space between a portion of the spindle surface and the spent ribbon accumulated on the spindle. A biasing structure is operatively associated with the spindle and the protruding segment for controllably biasedly directing the protruding segment through the protrusion bore in the spindle. A retracting structure is provided for controllably compressing and expanding the biasing means to controllably move the protruding segment through the protrusion bore.