Patent GB-191213315-A (GB)
Title: Improvements in Motor-operating and Key-locking Mechanisms for Combined Typewriting and Computing Machines.
Inventor: HART FREDERICK ARTHUR
Filed: 1912-06-06
Granted: 1913-06-05
Abstract: 13,315. Hart, F. A. Sept. 20, 1911, [Convention date]. Adding-apparatus; attachments to typewriters; operating by motors.-In a combined typewriting and computing machine of the Underwood-Hanson type, means are provided for effecting, after the setting of an item, the covering of the numeral keys and of the totalizer so as to prevent a key from being depressed or a total being taken during the forward movement of the general operator. Devices on the typewriter carriage automatically operate the covering-mechanism and close an electric circuit, thereby operating an electric switch and clutch to start a motor to drive the computing-mechanism. The typewriter carriage is provided with an adjustable tappet or dog 13 adapted to rock in succession levers 15 for depressing links 18 to rock levers 19, which in the usual manner raise the actuating rack-bars 21 so as to position one of a series of pins mounted therein, depending on the key depressed. A bar 31 on the general operator, when this is operated, drives the rack-bars to actuate the totalizer wheels 24. The operation is effected by an electric motor 37, which, through worm gearing, actuates a shaft 43 whereon is mounted a crank-arm having a slide 45 mounted in a slotted bar 46 which engages a yoke 47 on the side frame of the general operator. The left-hand lever 15 rests on a link 18 which engages a bell-crank lever 82, under one arm of which is a pin 85 of insulating-material connected to a terminal 86 and adapted to engage a terminal 87, thus completing an electro-magnetic circuit to rock a lever 52 controlling the starting-switch and clutch of the motor 37. The circuit remains completed sufficiently long to start the motor. The lever 52 may be rocked by means of a key 48 and link 49. A special lever 15, when raised, depresses a link 18<a> to draw back a latch 106 from a notch 108 in an arm 104, which, through a spring 105 and bell-crank lever 111, is raised, and, through an arm and bar 96, covers the keys and at the same time swings a shutter 97 to cover the totalizer. This covering-mechanism is released by the movement of the general operator by means of a bell-crank lever 113 which engages a notch 114 in a side frame of the operator and thereby swings the bell-crank lever 111 to depress the arm 104. The Specification as open to inspection under Section 91 (3) (a) comprises also a combined switch and clutch, Fig. 6, to start the motor and drive the computing-mechanism. The starting-bar 52, which is rocked on depression of a key 48 or automatically by the tappet on the typewriter carriage, raises the pin 53, which normally holds an arm 55 of a ring 68 against a shoulder 56 of a ring 57 frictionally mounted on the hub of a worm-wheel on the shaft 43. On the ring 68 is mounted an annular conducting-ring 69 having an insulating-segment 70, against which normally bears the end of one of the brushes 73, 74, Fig. 2. When the pin 53 is raised, the segment is rotated and the motor circuit is completed, thereby rotating the worm-wheel in a counter clockwise direction and carrying the ring 57 with it, thus forcing the rollers 64<a>, mounted in recesses on the ring, into the cam-portions of a cup-shaped member 65 fixed on the shaft 43, thereby rotating this shaft to operate the general operator. This subject-matter does not appear in the Specification as accepted.