Patent GB-786038-A (GB)
Title: Improvements in typewriters and other keyboard operated machines
IPC: B41J19/64
Filed: 1950-06-23
Abstract: 786,038. Typewriters. DIRKS, G. June 23, 1950 [Oct. 1, 1948], No. 37219/54. Divided out of 786,021 [Group XIX]. Class 100(4) A typewriter or like machine is arranged so that in each line the first actuation of the space key, a punctuation key, or the hyphen key after a predetermined number of letter spaces have been traversed, sets the machine for a new line. Automatic justifying arrangements are also described. As applied to an ordinary typewriter, an electrical contact 12, Fig. 6, is closed by the moving carriage ten to fifteen letter spaces before the end of a maximum line. The resulting energization of winding I of relay 13 establishes a holding circuit through winding II and changes over a switch arm 13b so that subsequent closure of contacts 14 by operation of the space bar or a punctuation key, &c. energizes a relay 15 which operates the carriage return mechanism. A delayed-action relay 17 then opens contacts 18 de-energizing the relay 13. In a typing machine of the type described in Specifications 786,022, 786,037 and 786,039 [Group XIX] data entered by keyboard is first stored on a magnetic drum 2, Fig. 1. A circumferential track on the drum is available for each line to be typed. During reading out, within (say) ten to fifteen letter spaces from the end of a line, a contact 21, Fig. 2, begins to traverse a series of contacts 23<SP>1</SP> . . . . 23<SP>n</SP>. Each time a tube 24<SP>1</SP>. 24<SP>2</SP> . . . &c. is fired by the sensing of a character signal, a relay 26 is energized; this moves a contact arm 30 over to contact 27a and steps on 'the contact 21. Also, with each rotation of the drum 2, Fig. 1, a tooth of a disc 7 passes a coil 39 causing a voltage surge which is applied to the grid of a gas tube 29. Since, however, the anode supply to this tube is cut off each time a character is sensed, the tube cannot fire until a hyphen, punctuation, or space signal is sensed. When this happens the tube 29 fires and a relay 28 operates to start a new line. Justifying arrangements. The firing of tube 29 completes a circuit through contact 21 and that one of a series of relays 22<SP>1</SP> ... 22<SP>n</SP> with which it is connected. The relay selected is therefore identified with the number of character-spaces in that particular line, and it is used to select one of a series of toothed pulse generator discs 3' ... 3<SP>n</SP>. In this series of discs the number of teeth per disc decreases progressively by one tooth for each successive disc and therefore the frequency of pulse signals picked up by each set of three equallyspaced sensing heads' 4<SP>1</SP> . . . 4", 5<SP>1</SP> . . . 5", decreases accordingly. These signals are used to control the speed of the motor which drives the printing device across one line of the paper. Therefore with a smaller number of character-spaces counted by the contact 21 that relay 22<SP>n</SP> is energized which will select the set of heads 4", 5<SP>n</SP>, &c. which will pick up higher frequency signals for traversing the printing device more rapidly to "stretch out" the line of characters. Conversely, where the number of characters in a line approaches the maximum allowable, a source of pulses at lower frequency controls the traversing motor so as to fit a greater number of characters in the same length. Specifications 786,033 and 786,041 [both in Group XIX] also are referred to.