Patent GB-818480-A (GB)
Title: Improvements in or relating to apparatus for transferring data in either direction between a computer and a mechanical calculating machine
Inventor: SAXBY FRANK REGINALD
Filed: 1954-11-03
Abstract: 818,480. Digital electric calculating-apparatus. NATIONAL CASH REGISTER CO. Ltd. Nov. 3, 1955 [Nov. 3, 1954], No. 31797/54. Class 106 (1). In a computing system including a mechanical rack-operated calculating machine and a computer having storage means settable according to a combinational code, data conversion apparatus for transferring data in either direction comprises a set of individually actuatable members associated with a device carried by a movable rack of the calculating machine, the members actuated determining, or being determined by, the differential setting of the rack, according to whether data is being transferred to or from the calculating machine. Apparatus for translating a decimal digit, represented by the differential position of a rack in a mechanical calculating machine as described in Specification 680,992, into a binary 1, 2, 4, 8 code representation by selective energization of four gas discharge storage tubes V 1 -V 4 , Fig. 2, in an electronic computer and vice versa, is described, similar arrangements being provided for the. transfer of the other digits of a number. The members comprise four lever plates 5-8, Fig. 1, corresponding to 1, 2, 4, 8 respectively and having serrations, positioned according to the code, which coact with the wide nose portion 4 of a spring-biased pawl 1 carried by a block 2 clamped to the rack. The plates may be raised by corresponding solenoids SL 1 -SL 4 , Fig. 2, which are energized through contacts A-D of relays MA-MD in the cathode circuits of the discharge tubes. The movement of the pawl is controlled by zero stop plate 9 which is raised by spring 16 from the position shown when cam rod 17 is rotated through 180 degrees by solenoid LE. Cams on shaft. 21, driven from the main shaft of the mechanical machine, close timing contacts such as CF, in the transfer control circuit, Fig. 2. Reference is made to the use of a non-decimal e.g. sterling mechanical computer. Transferring data from mechanical machine to electronic computer.-When the motor bar (not shown) of the mechanical calculating machine is depressed, the racks are moved in accordance with a number set up on the keyboard. " Reading " contacts X associated with stops on the form bar of the machine are closed if a number is to be transferred to the electronic computer, whereby an impulse from the latter energizes relay RR which operates contacts R 1 -R 4 . After the racks and therefore the pawls, such as 1, have been positioned, cam contacts CF 1  close to energize relay RB which closes contacts B 1 -B 5  thereby energizing all the relays MAMD which close their contacts A-D. Solenoids SL 1 -SL 4  are thus energized, but only those lever plates which have a serration in register with the pawl 1 are able to rise and close corresponding contacts L 1 -L 4  to apply triggering pulses to tubes V 1 -V 4 ; thus if, e.g., the pawl is in the position corresponding to digit " 5," only plates 5 and 7 (corresponding to " 1 " and " 4 ") will be raised thereby triggering tubes V 1  and V 3 . For each tube fired, an output pulse is applied over a lead such as P 1 . Transferring data from electronic computer to mechanical machine.-Pulses representing in binary form a decimal digit to be transferred are applied selectively over lines U 1 -U 4  to the triggering inputs of storage tubes V 1 -V 4 . " Set " contacts Y are closed for a transfer to the mechanical calculating machine, whereby relay RS is energized and closes contacts S 1 - S 3 . A " setting " signal is applied via contacts S 2  and line 24 to the electronic computer which then sends a pulse over line 25 to energize solenoid LM which operates the motor bar of the mechanical calculating machine. Near the beginning of the main shaft cycle, cam contacts CD, CC close, thereby energizing stop-plateraising solenoid LE through contacts E 1  of relay RE, and energizing those solenoids SL 1 - SL 4  corresponding to the stored digit, through contacts S 3  and contacts A-D; thus if, e.g., the digit " 5 " is stored by triggering tubes V 1  and V 3  and energizing relays MA and MC, solenoids SL 1  and SL 3  will be energized through closed contacts A and C. The energized solenoids will raise the corresponding lever plates (e.g. 5 and 7), thereby lifting the pawl nose 4 over the projection 13 on stop plate 9. The racks and pawls are then advanced; when the pawl 1 reaches aligned serrations in the raised lever plate(s) it drops and prevents further rack movement, a rack thus being differentially positioned in accordance with the lever plate(s) selected. Printing segments controlled by the racks effect printing of the number thus entered. The racks are subsequently restored, and cam contacts CF energize solenoid LF, Figs. 1 and 2, through contacts F 1  of relay RF, thereby restoring the cam rod 17 and stop plate 9 to the position shown.