JPS5633974A - Ribbon-feeding device of ribbon cassette - Google Patents

Abstract

PURPOSE: To feed the ribbon with little load and a fixed tensile force by a method wherein one endless belt running constantly in contact with the outer-peripheral surface of the ribbon rolled round a roll-out ribbon core and a roll-up ribbon core is provided inside the ribbon cassette.

CONSTITUTION: Inside the ribbon cassette 7, a driving roller 16 is provided on the front side of the cassette, while on the rear side thereof two rollers 17 and 18 are provided in such a manner that these rollers, together with the driving roller 16, form nearly an equilateral triangle, and an endless belt 19 is stretched through these three rollers. On the occasion, these members are arranged so that the side A of the belt 19 forming the triangle becomes a tangent line of the roll-out ribbon core 9 and the side C thereof becomes a tangent line of the roll-up ribbon core 13. Accordingly, at the initial stage of rolling-out, the diameter of the rolled ribbon on the roll-out ribbon core 9 is large and thus the side A of the belt 19 contacting with the outer- peripheral surface of the ribbon 8 is curved to a large extent, while on the side C the roll-up ribbon core 13 contacts with the belt tangentially. At the final stage of rolling-out, the relations turn to be reverse.

COPYRIGHT: (C)1981,JPO&Japio