Patent GB-191324989-A (GB)
Title: Improvements in Typewriting Machines.
Inventor: JAMES REGINALD WILLIAM
IPC: B41J7/02
Filed: 1913-11-03
Granted: 1914-04-30
Abstract: 24,989. James, R. W., [Remington Typewriter Co ]. Nov. 3. Type - lever a c t i o n s ; keys.-(1) The key-levers 11 are pivoted on axles 12 and are connected by vertical push-links 13 to bell-crank sub-levers 14 which are connected by draw-links 15 to the front-strike type-levers 16. The action imparts an accelerated motion to the type-levers, the acceleration being caused mainly by the links 13 approaching the pivot 30 of the sub-levers, and by the front arms of the sublevers approaching the normal to the links 15. T h e typelevers a r e pivoted in a segment 18, and the sub-levers may be arranged in a segment, but preferably the sublevers are pivoted on a straight wire 30, as shown, and the links 13 are made of uniform length. The pivot-wire 34 of the type-levers is arranged in a slot 35, ar d is secured by the engagement of the heads of screws 36. As the type-levers at the middle of the segment are lifted more directly than the type-levers at the sides of the segment, the action is arranged so that the keys of the middle type-levers have a greater initial leverage than those at the sides of the segment, the touch of the keys thus being equalized. For this purpose, the links 15 of the side type-levers and the middle type-levers are arranged, as shown in Fig. 1, to slope respectively downwards and upwards to the sub-levers, so that the initial angle between the side links and their sub-levers is less than the initial angle between the middle links and their sub-levers. (2) To provide a uniform dip, the keys 10 and the axles 12 are arranged in the known manner in three rows at different levels, the key-levers of the top, middle, and bottom rows being pivoted respectively on the top, middle and bottom axles. The key-levers of all the rows have the same leverage, and the keys are adapted to move vertically by arranging the n so that they are slightly above their axles at the beginning of the stroke and slightly below their axles at the end of the stroke. (3) The type-levers rest on a pad 47 consisting of a cork cushion clamped in a sheetmetal case 46 secured to arms 48 on the segment 18. (4) Returning-springs 24 are arranged between the rear ends of the key-levers and hooks 25 formed on a thin plate 26 riveted to a plate 27 which is secured by screws 28 to the framework, the screws passing through slots 29 which permit of adjustment of the tension of the springs. (5) To facilitate assembling, the key-levers and the axles 12 are adapted to be inserted bodily, the axles being secured by screws 23 to brackets 20 on a cross-bar 21 which is secured by screws to the side bars 1 of the framework. The key-levers are spaced apart on the axles by sleeves 19. The brackets 20 carry also the axle 82 of the space-bar levers 81. The sub-levers and the type-levers are preferably mounted in a detachable case-shift frame, described below, and the links 13 are readily detachable. (6) The type-levers may each carry three types 17, and either a platen-shift or a caseshift may be provided. Case shift mechanism.-The type-levers and the sub-levers may be mounted in a frame 37 provided witharms 40 pivoted at 41 to brackets 42 on the framework, the pivots being disposed as described below in such a manner that the case-shift can be effected without disturbing the action, the links 13 merely swinging slightly to the front or rear according as to whether the segment is shifted up or down. For this purpose, the axis of the pivots 41 is arranged in the same plane, horizontal in the machine shown, as the printing point and the axis of the platen ; further, the axis of the pivots 41 is arranged in the plane of the links 13, and the upper ends of these links are nearer than the printing point to the axis of the pivots so that the movement of the upper ends of the links is slight. The shift-frame is balanced by a spring 50. The shift-frame consists of a casting formed with the segment 18 and a slotted guide 32 for the sublevers. The shift-frame and the type-levers and sub-levers are inserted bodily when the machine is being assembled. Shift-key actions.-The shift-key levers 55, 56 are secured to levers 57, 58 which are mounted on a common pivot 60 and are respectively formed with cam-slots 71, 66, Fig. 2, adapted to engage co-axial rollers 72, 67 on the shift-frame. The shift-frame is held in the middle position by the engagement of the roller 72 with a ledge 75 on the lever 57. and the engagement of the roller 67 with a ledge 76 on the lever 58. The cam-slots 71, 66 are adapted respectively to depress and to raise the shift-frame. The lever 58 is formed with a bend 65 to afford clearance for the action of the lever 57. The pivot 60 is mounted on a support 61, which is fulcrumed at 63 on the cross-bar 21 and is engaged by adjusting-screws 62 which are manipulated to adjust the position of the shift-frame. The throw of the levers 57, 58 is adjusted by means of stop-screws 77 which are locked by studs 78.