GB210857A - Improvements in ribbon vibrator mechanisms for typewriting machines - Google Patents

Abstract

210,857. Brougham, F. J., (Addograph Co.). Nov. 7, 1922. Ink-ribbon mechanism; driving-mechanism.- A ribbon-vibrator, which may be adjustable for multicolour, stencilling, and case-shift, is actuated by a spring, and is retracted in opposition to the spring by means of a rotary motor. The vibrator 27 is carried by a bell-crank 28 engaging a push-bar 34 connected to a rocking frame 25 which is associated with the key-controlled devices described in Specifications 25038/13 and 210,894 for actuating type-levers, the devices comprising an actuating-spring 26, and a ratchetcoupling on a shaft driven by a rotary motor. On depressing the keys, the rocking-frame is released and actuates the vibrator and type-levers, whereupon the ratchet-coupling is thrown in, and theparts are retracted by means of the motor. A spring 36 retains the bell-crank in engagement when the push-bar is retracted, and serves also to cushion the forward movement of the pushbar. To compensate for platen-shift, a pivoted arm 31 supporting the bell-crank is connected by a link 38 to the push-bar 34, and by a link 39 to a member of the shift-mechanism, for instance to the rock-arm 40, forming part of the shiftmechanism described in Specification 208,767. For two-colour adjustment, the push-bar can be moved laterally to place either of two fingers 44 thereon in engagement with the bell-crank; or for stencilling, the push-bar is moved into a mid-position, neither finger being then in engagement. The push-bar is moved by means of a slide 47 which is actuated by a cranked shaft 48, and is formed with a slotted arm 46 engaging a finger 45 on the push-bar. The cranked shaft is operated by a knob having a finger arranged over a colour-indicating plate. The slide is provided with projections 47a for engaging a detent.