Patent GB-189820254-A (GB)
Title: Improvements in or relating to Typewriting Machines.
Inventor: FOLEY JAMES SAMUEL
Filed: 1898-09-24
Granted: 1899-09-09
Abstract: 20,254. Foley, J. S., Salter, G., Bache, T. P., Birch, J. H., and Salter, T. H., [trading as Salter & Co., G.]. Sept. 24. Type-writers.-The platen roller is carried in bearings in a frame free to move in a path at rightangles to its length in guides in the main carriage. The platen frame is provided with a groove into which fits a guide-rail which can be actuated by suitable key levers so as to shift the platen for printing upper or lower case type &c. The main carriage is provided with an escapement spacing- mechanism of known pattern. The pressure of the scale bar on the platen is produced by helical springs of adjustable tension, and to prevent play between the platen frame and the carriage a flat spring is provided which is fastened to the carriage and bears against one end of the platen frame. The inking-device consists of a ribbon wound from one spool on to another and automatically reversed when either spool is empty. The inking-ribbon mechanism is carried by a shield or plate G shown in inverted plan view in Fig. 6. The shield is pivoted so that it can be thrown upwards clear of the platen when required. The spools N, of which one only is shown in Fig. 8, are toothed so as to gear with long pinions G<4> driven from toothed wheels G<5>. A plate H having a limited sliding movement on the shield G carries toothed wheels H<2> which gear with a rack F mounted upon the main carriage. The axles of the wheels H<2> pass through the plate H and terminate in cranks J, Fig. 6, to which are loosely pivoted rings J', Fig. 10, having internal pawls J<2> engaging with teeth K<2> cut upon the sleeves K<1> of toothed wheels K, Fig. 6. The ratchet driving-gear so constituted works more smoothly than one with spring-controlled pawls. According to the position of the sliding plate H, either the left-hand wheel K, Fig. 6, gears with the wheel G<5> through the medium of a pinion K<3> or the right-hand wheel K gears directly with the other wheel G<5>. The shifting of the plate H therefore produces a reversal of the inking-ribbon. The plate H is shifted in the following manner :-A segment plate L<4> journalled in part of the plate G gears with the rack F. On its axle is an eccentric L<3> passing through a slot in the plate H, which is caused to slide when the eccentric turns. On the further end of the same axle is a cam L, Fig. 9, in engagement with a spring-pressed roller L<2>, which in the position shown tends to turn the cam against the action of the stop M<1>, of which there are two carried by a sliding plate M. As a spool fills a finger O, Fig. 8, moves outwards until its shorter arm, which presses against the end M<3> of the plate M, causes the latter to move sufficiently to release the stop M' then in action. The roller L<2> then turns the cam sufficiently to throw the segment plate L<4> into gear with the rack F, the eccentric L<3> being thereby turned as the carriage advances and the plate H shifted so as to reverse the ribbon. The segment plate soon passes out of gear with the rack F and remains at rest until the cam L is once more actuated by the filling of the other spool. The ribbon passes over the impression point through guides which can be drawn back to expose the line last written. The ribbon is attached to the spool by inserting its end in a small circular hole made in the hollow hub of the spool.