GB773270A - Impression control for typewriting machine - Google Patents

Abstract

773,270. Typewriters. UNDERWOOD CORPORATION. July 18, 1955 [Nov 19, 1954], No. 20694/55. Class 100(4) In a power operated typewriter of the kind having a type-lever 11 that effects printing by means of a sub-lever 16 in contact with a lever 20 operated by an actuator 22 from a power roll 10, case shift means is provided for changing the position of the type 36, 37 and, at the same time, adjust the relative positions of the pivots 17 and 18 of the sub-lever 16 and lever 20 respectively. The adjustment of the position of the pivots alters the point of contact between the sub-lever and lever so that the total distance that the typelever is driven for any particular motion of the actuator 22 increases as the initial contact between the lever 20 and the circular surface 21 of the sub-lever 16 is moved away from the pivot. Movement of the pivot 17 is effected by swinging the pivot mounting 40 about a rod 41 by means of a link 43 connected to a case-shiftable yoke 44 adjustably connected to a pintle 47 secured to a type segment 14. The yoke 44 is moved to effect case-shift and adjustment of the mounting 40 by a strap 49 embracing a rotatable disc 50 eccentrically mounted upon a bearing portion of the power roll 10. Upon operation of a caseshift a lever 53 is rocked clear of a pawl 52 on the disc 50, whereupon pawl 52 engages toothed member 51 and after onehalf of a revolution is disengaged by a hooked lever 57. This half-revolution of disc 50 swings the yoke 44 which moves to lower-case position. U.S.A. Specification 2,275,759 is referred to.