Patent GB-667767-A (GB)
Title: Improvements in or relating to typewriting machines
IPC: B41J3/37
Filed: 1948-10-06
Abstract: 667,767. Typewriters &c. KLEIN, E., and GAL, E. Oct. 6, 1948, No. 26103/48. [A Specification was laid open to inspection under Sect. 91 of the Acts, April 9, 1949.] Class 100 (iv). The keys of a typewriter are formed with projecting arms 10 of various lengths pivotally attached to the free ends of levers 37 pivotally mounted on a common shaft 38 and which are operatively connected to type-levers 3, the arms 10 being prevented from upward pivotal movement after release by means of a transverse bar 50. Each type lever 3 is pivoted on a horizontal arcuate shaft 2 and is actuated by toothed gearing from a lever 4 pivoted on a shaft 5, the lever 4 having a link 6 connecting it with its lever 37; all three shafts 2, 5, 38 are assembled in a mounting 1. The levers 37 have an upright portion 7 to which the arms 10 are pivoted at 9 for folding, so that when the transverse bar 50 is moved anticlockwise about shafts 48, 48a against pressure of springs 51, 51a all the keys are folded into the position indicated by dotted lines, where they are held by a cover of the typewriter. The bar 50 is positioned close to a curved front edge 53 of depending dogs 11 the edge having a centre of curvature in the shaft 38 so that the distance between the bar 50 and edges 53 remains constant when the keys are depressed to transmit action through a stud 12 engaging an abutment 13 on the portion 7 of the lever 37. The Specification as open to inspection under Sect. 91 comprises also mechanisms which actuate a control plate 16 engaged by protrusions 15 spaced at varying distances from shaft 38 so that the unequal movement of key-levers 10 due to their different lengths is translated into equal movements of the control plate 16. The control plate 16 rocks a shaft 18 which is coupled to (a) the space-bar mechanism via levers 44, 44a and rod 47 (b) the ribbon-spool mechanism via levers 44, 44a and rods 46 (c) the escapement mechanism via a block 20, attached to shaft 18, pivot- and-link 21, 22 and operating extension 23, and (d) the ribbon vibrator 26 connected to the link 22. The force of impact of each type lever may be adjusted by suitably shaping noses 61 on the levers which strike a collar 28 fixed to the mounting member 1. In a modification, Fig. 6 (Cancelled), the toothed lever 4 driving the type levers is connected to the levers 37 by a pin.and slot connection 65, 66, the lever 4 being urged into rest position by a coil spring clamped by an arcuate toothed member 69 to an arcuate element 100. The adjustable contact between the key lever and the control plate 16 comprises studs 99 connected to springs 97 resiliently surrounding the lever 37 so that the studs can be moved to lodge in one of the various notches 98 on the underside of the key levers. The plate 16 is carried on arms 73, 73a and is resiliently attached by springs 75, 75a to arms 76, 76a clamped to the control shaft 18. The touch of the keyboard is adjustable by means of a screwcontrol indicating-device 92-96 connected by a tensioning spring 91 attached to arms 90, 90a fixed to the control shaft 18. Shaft 18 also carries a lever 78 in which a stud 80 is screwed. The head of the screw engages a notch in the end of another lever 81 freely rotatable on the shaft 18 and connected by a stud 83 and linkage 84- 87 to the escapement device. Thus by the relative displacement of the two levers 78, 81 adjustment may be made to the escapement mechanism. The construction is arranged so that the type-basket together with the components mounted therein forms a separate pre-adjustable unit which is subsequently fixed to the frame of the typewriter. This subject-matter does not appear in the Specification as accepted.