GB635916A - Typewriting machine - Google Patents

Abstract

635,916. Typewriters. UNDERWOOD CORPORATION. May 30, 1947, No. 14445. Convention date, Dec. 3; 1938. [Class 100 (iv)] In a power-driven typewriter of the kind having a semi-circular array of type levers which are spring-urged towards inoperative positions and are connected to their operating levers at graded lengths from the pivots of said levers and having selectively operated pusher actuators arranged in a straight row adjacent a continuously-operating power source associated with the type-levers, the actuators 34 are normally spring-held against a stationary abutment 35 free from the power source 38 and have vertical arms 28 pivoted thereto which are in individually formed rolling contact with their associated type-bar operating levers 21 to transmit, when operated, equal power movements to the type bars. The actuators 34 are selected by the key levers 41 by the engagement of a hooked member 69 with a projection 52 on the actuators 34 and upon depression a pawl 37 on the end of actuator 34, held by gravity in an anticlockwise direction, is engaged by the power drive 38. A spring 36 ensures that there is no movement of actuator 34 until good contact is made between parts 37, 38 and until the pawl 37 is halted by a stop 56. The spring also causes immediate return of the actuator to normal position in advance of and independently of the return of the type-bars 11 and operating lever 21 to normal positions. The levers 21 are mounted on a straight axis 23 and connected to the type-lever 11 by connecting- rods 19, and the points of connection 26 at graded lengths from the axis 23 lie on a vertical arc in front of an arc along which the links 19 are connected to the type-bars 11. Each lever 21 has a differently-shaped contacting surface 68 so that the action of the parts 28, 34 thereon in combination with the varying leverages of levers 21 ensures that equal power is given to the typebars. Disengagement of the actuators 34 from the power drive 38 is effected by surfaces 58 engaging a head 59 of individually adjustable screws mounted in a universal bar 60. Bar 60 is carried on pivoting arms 61, 62 so that the power imparted to all actuators 34 can be simultaneously adjusted by movement of the arms about a pivot 23 against the tension of a spring 66 and adjustably positioned by the rotation of an eccentric 64 attached to a dial control 65. Ink-ribbon feeds and vibrator mechanism. Extensions 75 of the levers 21 are of varying length to compensate for their differing angular movements and impart a constant movement to the universal bar 74 connected to the ribbon mechanism. Tongues 72 on the bar 74 are bendable to compensate for small differences in the throw of the levers 75.