GB736976A - Typewriters - Google Patents

Abstract

736,976. Typewriters. VALMOR, Ltd. Aug. 25, 1953 [Sept. 15, 1952; Jan. 13, 1953], Nos. 23137/52 and 972/53. Class 100 (4). Ink - ribbon mechanism.- A duplicating arrangement for a typewriter comprises a hectograph ribbon 16 fed along the printing line from a supply spool mounted in a detachable casing 15 to a feeding roller 32, so that the ribbon is fed a distance equal to a character width at each letter-space movement of the typewriter carriage. The feeding roller 32 is held against rotation during carriage return movement so that a new length of ribbon is drawn into place. The spool 15 and roller 32 are mounted on brackets 12, 11 attached to the sides of the machine and roller 32 is driven by a coiled spring attached to the roller shaft and to a drum 39. The drum is substantially the same diameter as the feed roller 32 and is rotated to wind up the spring during carriage return movements by a flexible band 42 attached to the typewriter carriage. A pawl 40 on the drum free-wheels over ratchet-wheel 38 attached to the roller 32, so that it is not rotated backwardly. The casing 15 is pivotally mounted so that a lip forming an exit slot for the ribbon bears on it and maintains it in tension. The supply spool is formed with grooves so that only spools so provided will fit corresponding projections on the rotatable spool support and slipping between the two is prevented. Sheet guiding arrangements. To facilitate the entry, either from the front or the back of the platen, of a sheet between the ribbon 16 and a front ribbon guide 26, Fig. 6, the plate 45 is hingeable a limited amount at 46.