GB371652A - Improvements in and relating to typewriting machines - Google Patents

Abstract

371,652. Typewriters. SMITH & CORONA TYPEWRITERS, Ltd., L. C. and HICKMAN, V., Melbourne House, Aldwych, London. June 2, 1931, No. 16078. [Class 100 (iv).] Paper carriages and supports; web-feeding arrangements; line-spacing mechanism.-In a typewriting-machine for writing in a single line upon a continuous strip, having a spring- driven carriage whose traverse is regulated by key action, a platen roller 11 is provided which is intermittently rotated by the advancing motion of the carriage 4. The roller 11 is held against rectilinear movement by a forked guide-member fixed to the machine and is mounted upon a detachable shaft 12, formed with a helical rib 15 engaging a corresponding recess on the roller 11, so that the latter is turned as the carriage 4 and shaft 12 are traversed. The strip 25 is brought through a fixed guide 20a and a movable guide 21, formed of a light spring-strip and attached at one end to the carriage-return lever 22, and thence to a.clutch formed by the lever 22 and its supporting-bracket 23, such that the strip is clutched when the lever 22 is operated to return the carriage, thereby drawing a length of strip from the spool sufficient for the succeeding traverse movement of the carriage. At other times, the clutch is held open by spring means. The strip then passes through a guide ring 27 attached to the bracket 23 and through tubular guide members 28, between which is mounted the platen 11, and an automatic feed at a rate corresponding to that of the traverse of the carriage is obtained by rollers 29, 30, Fig. 3, the former being pivotally mounted in a frame 31 and spring-pressed against the roller 30. The latter is mounted on a shaft having a ratchet 32 and co-operating pawl at one end to permit rotation in one direction only, such rotation being produced by a rack 38 on the carriage, acting through gears 37, 34 and a one-way ratchet 35 which is free to rise axially upon the shaft against the spring 36 if the pinion 34 turns in the reverse direction. In operation the strip 25 is passed through the clutch device 22, 23 and the guides 27, 28, the feed-rollers 29, 30 being temporarily separated. The carriage is moved to the right by the lever 22, closing the clutch, to withdraw a length of strip corresponding to the traverse movement of the carriage, and the machine is then ready for use. Ink-ribbon mechanism. One or more ribbons may be provided at the back or front of the strip, or two ribbons may be employed, one operating at the front and the other 48 at the back of the strip for obtaining denser impressions. The four ribbon spools are mounted in pairs upon shafts operating in the usual manner to feed the ribbon from one spool to the other, and the ribbon inking the back of the strip is led thereto through slots 51 .. 54 in a ribbon guide 50, Fig. 5, being normally held out of contact with the strip by resilient members 56, 57. The ribbon guide for the front ribbon is pivotally mounted on the upper part of the member 28 so that it can be turned up when the ribbon is to be disengaged therefrom. By temporarily displacing the ribbons, the machine may be used for stencilling.