GB682212A - Power-driven mechanism for operating type bars and other instrumentalities of typewriter or like machines - Google Patents

Abstract

682,212. Typewriters &c. ROYAL TYPEWRITER CO., Inc. May 25, 1950 [July 1, 1949], No. 13208/50. Class 100 (iv). A power operated typewriter or like machine comprises a rotating snatch roll 9, Fig. 3, and a driving pulley 69 whose effective diameter on which a driving belt 68 engages can be varied to adjust the speed of the pulley and snatch roll 9 to vary the face transmitted to the various operated parts e.g. a typelever mechanism as shown in Fig. 9. The key-lever mechanism is similar to that described in Specification 674,941, but means are provided whereby the force of the impression of individual type-levers may be adjusted, and comprises an extension 46 of the actuator 10 which can be bent into various positions as indicated at 46a and 46b so that the extent to which the actuator pawl nose 23a enters a tooth space on the snatch roll 9 is controlled. If the extension 46 is moved into position 46b the pawl 23 makes a greater clockwise movement and the drive of the snatch roll on the nose 23a is accordingly greater.' The means whereby the power to actuate the type levers or other mechanisms is collectively adjusted, comprises a drive to the variable diameter driving pulley 69, driven from a constant speed source D, Fig. 6, geared down by belt and pulley drives 50-60 driving a shaft 61 carrying a V-groove pulley 67 around which is trained a belt 68 rotating the variable diameter pulley 69. This pulley comprises an axially fixed flange 84, Fig. 3, and an axially slidable flange 90 rotatably secured to a pin 80 secured to the snatch roll 9. To adjust the effective diameter of the pulley the distance between the two flanges 84, 90 is adjusted, the slack in the belt 68 being taken up by a pair of spring loaded jockey pulleys. Flange 90 transmits rotation to the flange 84 through a slotted collar 93, keyed to the pin 80 and engaging a pin 96 extending from the flange 84. Axial movement imparted to the flange 90 is derived from a knob 108 carrying markings on a surface M which are aligned with a pointer 113 formed in the framework 114. The knob is rotatable between fixed limits to turn a screw 104 in a bushing 100 to transmit, through a ball 102 and a pin 79, an axial movement to the snatch roll 9 and pin 80 against the pressure of a return spring 107. Carriage-returning mechanism. - Carriagereturn movement is effected by a mechanism actuated from the snatch roll 9 as described in Specification 674,943 operating a fork 132, Fig. 6, which axially moves a cone 130 leftwardly spreading clutch-engaging fingers 131 which operate to expand a ring 129 to transmit the drive from the motor driven shaft 61 to a drum 128 on which is wound a carriage-pulling band 125.