GB191324990A - Improvements in Typewriting Machines. - Google Patents

Abstract

24,990. James, R. W., [Remington Typewriter Co.]. Nov. 3. Case-shift mechanism; shift - key actions. - In machines in which the shiftable part can occupy three positions, the shift mechanism comprises two toggles arranged so that the part is held in the normal position, when both toggles are straight, and is moved into the other two shift positions by bending one or other of the toggles. The arrangement is shown as applied to the type-lever action described in Specif i c a t i o n 24,989/13, in which the shiftable part consists of a frame 16 which is pivoted at 17 and is provided w.th a segment 13 for typelevers 10. A lever 37 pivoted at 36 to an offset plate 34 on the left-hand bar of the frame 16 is connected at 39 to a toggle 38, 40, and is connected at 53 to a toggle 52, 55, the arms 40, 55 of the toggles being respectively pivoted at 41, 48 to the fixed framework a n d being connected by a link 50 to a shift-lever 47 pivoted at 48 and by a pin and slot 62 to a shift-lever 60 pivoted at 61. The arm 38 is formed with a finger 45 adapted to engage the arm 40 to prevent the toggle 38, 40 from being bent towards the rear, bending towards the front being restrained by a wire spring 44. The toggle 53, 55 is similarly prevented from being bent towards the front by a finger 57 on the arm 52, and is restrained from bending towards the rear by a wire spring 56. When both toggles are straight, the shift-frame is held accurately in the normal position, bending of the toggles in either direction being prevented by the fingers 45, 57 and the springs 44, 56. When the sbift-lever 60 is depressed, the toggle 52, 55 is bent towards the rear, as shown in Fig. 5, and the sbift-frame is depressed, the pivot 39 forming a fulcrum for the lever 37. When the shift-lever 47 is depressed, the toggle 38, 40 is bent towards the front and, as shown in Fig. 6, the shift-frame is lifted, the pivot 55 forming a fulcrum for the lever 37. The movements of the shift, frame are limited by the engagement of ears 66, 67 on the plate 34 which carries the lever 37 with the bevelled ends 74, 75, Fig. 7, of stops 68, 70, which are adjustably secured in a recessed bracket 73 by studs 72 passing through slots 71. Key locks.-(1) The shift-levers 47, 60 are formed with locking-ears 80 adapted to engage ears 82, 83 on a plate 88, which is pivoted at 90 and is engaged by a spring normally holding the plate vertical, with the ears 82, 83 out of the path of the ears 80. To lock either of the shift-levers in the depressed position, the plate 88 is tilted by means of a finger-piece 93 into the position shown. The locked shift-lever can be released by depressing it slightly. The ears 82, 83 are formed on independently adjustable plates 84, 85 secured to the plate 88 by studs 87 passing through slots. One of the plates 81, 85 is formed with the finger-piece 93. (2) Simultaneous depression of the shiftlevers 47, 60 is prevented by the engagement of a lug 76 on the lever 47 and with an ear 77 projecting from a lug 78 on the lever 60.