GB1231591A - - Google Patents

Abstract

1,231,591. Typewriters. INTERNATIONAL BUSINESS MACHINES CORP. 27 Aug., 1968 [18 Sept., 1967], No. 40817/68. Heading B6F. Power operated lever machines.-A power operated typewriter comprises type levers 22 connected to actuator members 15 by connecting links 21, each actuating member being selectively engageable with a reciprocable bail 28 by means of a corresponding key lever 11. Depression of a key 14 acts to urge an actuator member 15 leftwardly, a resilient finger 44 thereby being disengaged from a latching surface 43 on the actuator member, enabling the finger to lift a bail 46 which acts through a lever 47 to initiate engagement of a half-revolution clutch 48, so connecting the drive from a motor 50 to a drive shaft 34. A pair of cams 34 are thereby rotated, lifting the bail 28 to effect an impression. Key interlocks.-Simultaneous actuation of two or more type levers is prevented by a ball interlock 40 which will receive only one tail 38 of an actuator member 15. If a second key is depressed during the cycle of operation of a first key, the corresponding actuator member 15 travels far enough to release the finger 44 so that the clutch 48 remains engaged for a further half revolution to permit a corresponding impression action. Impact adjustment.-The actuator member 15 is driven by the bail 28 for a first part of its pivotal motion after which a projection 55 thereof strikes a rod 56 and the momentum of the actuator member and type lever carry them to effect impression. During the second part of the motion of the member 15, a tab 18 thereof engages the finger 44 which thereby controls the impact. Collective adjustment of the impact is effected by adjustment of the fulcrum of the fingers 44 by movement of a rod (61), Fig. 2, not shown. Letter-by-letter adjustment is achieved by screws 58, 59 which are selectively brought into operative position according to the case shift position. Rebound preventing.-The momentum of an actuator member 15 after impression is absorbed by a resilient finger (67, Fig. 2) which engages a surface 68 of the actuator member. Repeat power action preventing.-If the key lever is still depressed when the actuator member 15 returns after an impression action, the tab 18 strikes a camming surface 74 of the key lever and displaces the key lever out of operative position to prevent repeat action.