GB602869A - Electrical type-printing telegraphic apparatus - Google Patents

Abstract

602,869. Ink-ribbon mechanism. STANDARD TELEPHONES & CABLES, Ltd. (International Standard Electric Corporation). Oct. 13, 1944, No. 19789. [Class 100(iv)] [Also in Group XL(b)] In a printing telegraph receiver in which a printing 'tape and inking ribbon are associated with a type-wheel which can be rotated and moved axially to bring the selected character into the printing position (see Group XL(b)) the ribbon P90 is fed to and from rolls P192, P194 carried by ratchet wheels P191, P193, the winding' roll being driven from an arm P155 through a lever P158 carrying a doubleacting pawl member P190. When the ribbon is nearly unwound from one roll, for example, the roll 194, studs on the ribbon are arrested by pins P210, P211 on a member P204 having limited angular motion on a member P202 pivoted at P203. Further winding motion of the ratchet P191 rocks the member P202 clockwise and in this position a shoulder P225 on the double pawl P190 engages the projection P224 on the member P202 when the arm P158 is next operated so that the double pawl is rotated into engagement with the ratchet wheel P193, the operating tooth of the double pawl being shifted to engage with the teeth of the ratchet wheel by a toggle spring P195. A double-acting holding pawl P197 pivotally supported from a fixed plate P198 operates independently by the driving pawl P190 but is provided with a fork P201 which straddles the pin P196 of the pawl P190 so that it is moved with the latter to engage the appropriate ratchet wheel. In a modification, Figs. 7 to 11 (not shown), the printing tape is moved in a direction parallel to the axis of the type-wheel and at right angles to the direction of movement of the inking ribbon. The feed rollers for the inking ribbon are carried by a frame which is resiliently mounted on pivots.