GB147287A - Improvements in or relating to type-bar mechanisms - Google Patents

Abstract

147,287. Etheridge, H., and Bar-Lock Typewriter Co. April 16, 1919. Type-lever actions; case-shift mechanism. - Relates to actions in which the type-levers and sub-levers are mounted on a shift-segment, and the key-levers are connected to the sub-levers by links. (1) The key-levers G are connected to the sub-levers D by horizontal links F which are of such length that the ends connected to the keylevers are not moved appreciably when the segment A is shifted. The slight movement of the type-levers B that is produced by shifting the segment may be obviated by providing slack pivots or by arranging the links to pass from one side of the horizontal to the other. (2) The links F and the bottom ends of the sub-levers are arranged in one horizontal row or in as many horizontal rows as there are rows of keys. (3) The pivot G<1> of each key-lever G is, approximately, vertically above the pivot g of the associated link F, and the line of initial thrust of the link is approximately at right-angles to the bottom arm of the sub-lever. Initially, the line G<1> - - g is approximately at right-angles to the link. The key-levers are of bell-crank form, the longer arms carrying the keys. (4) The sublevers are pivoted on pins E<1>, as described below, and are formed at the top with offset radial parts D<1> which are provided with pins B<1>, engaging slots in the type-levers B. Initially, the line G<1> - - g of the middle key-lever is approximately parallel to the line B<1> - - b and the link is approximately parallel to a line drawn from the face of the type to the pivot of the type-lever. (5) The sub-levers D are pivoted in the forked ends E<1> of pillars E which are secured to the web G<1> of a frame C, secured to the segment A. The pillars are received by enlarged countersunk holes E<2> in the web and are secured by screws E<3> which pass through enlarged holes in the web and are screwed into the pillars, the arrangement permitting rotational and slight lateral adjustment of the pillars. The pillars are arranged in groups e, Fig. 2, of four, corresponding to four rows of keys.