GB839381A - Improvements in or relating to type-printing arrangements - Google Patents

Abstract

839,381. Typewriters. SAXBY, R. N. Nov. 26, 1957 [Dec. 15, 1956], No. 38333/56. Class 100(4) The type printing mechanism of Specification 791,800 is modified by the provision of a separate reversible motor for controlling carriage movement in letter or back spacing direction. As in the prior Specification line spacing is effected by a hollow shaft 91, Fig. 1, driven in either direction from a shaft 59 through bevel gearing 104, 105 or 104, 106 the alternative engagement of which is controlled by an electromagnet. The shaft 59 is driven intermittently to provide single line spacing as described in the prior Specification and provision is made to drive the shaft 59 continuously under the control of manual keys or signals received from a computer or similar machine. Letter and back spacing. As in the prior Specification single letter spacing is effected by a Geneva wheel 64, Fig. 4, acting through a pinion 66 and a rack 67. In addition continuous movement in either direction is effected on operation of the carriage magnet, an extension 145 of which forces down the spindle 138 to disengage a pin 144 from the Geneva wheel 64 and to connect a bevel wheel 134 with a toothed ring 140 of a member 139 which by a pin 141 drives the carriage through the spindle 138 and rack and pinion 67, 66. Downward movement of the spindle 138 closes a contact springset 146 to start the reversible motor. The carriage movement like the line spacing movement is controlled by manual keys or signals from a computer and in the latter case the drive is stopped by the control of a wiper moving over spaced contacts. Ink ribbon mechanism. Spools mounted on spindles 153, 154 are driven from a shaft 173, through bevel gears 167, 177 or 168, 178. The shaft 173 is driven by a pawl and ratchet 186, 174 from an electromagnet 189. The direction of the feed is reversed when an eyelet on the ribbon engages a fork 160 to close contacts 185 and energize an electromagnet 195 to move the shaft 173 to disengage the gearing 167, 177 and engage the gearing 168, 178 the feed is again reversed when the fork 159 is contacted to make contacts 184.