GB196248A - Improvements in or relating to ribbon spools for typewriting machines - Google Patents

Abstract

196,248. Smith & Bros. Typewriter Co., L. C., (Assignees of Gabrielson, C.). April 14, 1922, [Convention date]. Ink-ribbon mechanism.-A ribbon-spool comprises top and bottom flanges joined by a core, the bottom flange having cams co-operating with means for preventing the feed-reversing devices from forming an obstruction when the spool is being mounted on a typewriter. The spool comprises top and bottom flanges 24, 30 connected by a core 27 formed from a blank having lugs 28, 29, which engage apertures in the flanges and are headed or welded. For holding together the ends of the core, abutting lugs formed at the top and bottom corners of the blank engage common apertures in the top and bottom flanges. The top flange is dished and the bottom flange is formed with depressions 32 having cam surfaces 33 co-operating with the devices described below. The core is formed with a ribbon-attaching prong 63. The top flange is secured to a sleeve 25 fitting on a shaft 14 and formed with notches engaging lugs 19 formed on a collar 18 on the shaft. The spool is retained by means of a thumb-screw 21. The spool is associated with a known feed-reversing device comprising a spring- urged feeler 39, pivoted on a bracket 35 and having lugs 41, 43. When the ribbon has been unwound, the lug 41 projects through a slot 31 in the core, and the lug 43 engages a gear 16 on a constantly-rotating shaft 17, which thereupon rises to bring the gear into engagement with a gear 15 on the shaft 14. There is now provided a spring-urged lever 50, adapted to move the feeler inwards when the full spool is removed, the lever being normally restrained by the engagement of a finger 55 thereon with the core 27. When the fresh spool is mounted on the shaft 14, the bottom flange rests on the finger 55, and on turning the spool one of the cam surfaces 33 engages the finger and rocks the lever 50, thereby permitting the feeler to return to the normal position. When the end of the cam surface reaches the finger, the finger enters the core, and the spool drops to permit engagement of the sleeve 25 with the lugs 19.