Patent GB-997991-A (GB)
Title: Apparatus for recording data
IPC: G01D15/20
Filed: 1961-11-22
Abstract: 997,991. Data recording apparatus; photo-electric photometers. UNIVERSITY OF ADELAIDE. Nov. 22, 1961 [Nov. 24, 1960], No. 41717/61. Headings G1A and G1J. In data recording apparatus having a rotaryarm receiving potentiometer 50 mechanically connected, through worm 78 and gears 54, to a servomotor 53 which drives print-out counters 56, the print-out servomotor 53 is coupled to an amplifier 58 (the input for which is the error signal between the potentiometer 50 and a voltage output signal from the data sending equipment) whereby the servomotor rotation, and hence the setting of the counters, is a function of the position of the rotating arm of potentiometer 50. Independent timing means periodically energise a solenoid to bring the counters, which have raised type, into contact with a sheet. To this end the counter unit is mounted between a pair of rocker arms 84 (Fig. 3) pivoting on a shaft 74 held between a pair of parallel arms 83 of a frame 70. The latter also carries the motor 53 and is fixed to the frame of an electric typewriter with its keyboard and type arms removed. The solenoid 66 for controlling the axial shift of the platen 62 is linked to the rocker arms 84 and when energized in response to the independent timing means operates the print-out mechanism. When solenoid 66 becomes de-energized, the platen 62 is shifted in the normal way, During the printing out operation a solenoid 86 (also controlling the ribbon movement) is energized. This brings the toothed end of a locking rod 57 into engagement with a star wheel 76 on shaft 74 meshing through gearing with the counter pinion 81 whereby alignment of the characters on individual rollers of the counter 56 is ensured. As shown in Fig. 1 the data signal voltage is developed in a transmitting potentiometer 39 the rotating arm of which is driven by a servomotor 38 controlling the position of a light blanketing member 40 of a double-beam nullreading photometer and coupled to the output of an amplifier 37 fed by the photo-cell 36. An oscillating mirror 34 gives two beams one through and one to the side of a column of liquid the absorption of which is used to measure the amino-acid content of a protein sample. This is mixed in a vessel 10 containing an ion-exchange resin with buffer solutions of various pH-values pumped from reservoirs 12 and 13, then via a collecting vessel 18 to mixing vessel 20 where it is heated and mixed with ninhydrin reagents from reservoirs 22. There are nine test columns 10 each of which is tested in turn, Liquid is discharged from vessel 20 to the transparent photometer vessel 29 by means of a solenoid-operated value 28. After the measurement independent timing means, which controls each step in the process, opens value 44 so that a further sample may be tested and the print-out mechanism is operated as previously described. Because the transmission of the sample is an exponential function of the absorption coefficient, potentiometer 50 is wound so that potential varies logarithmically with rotational displacement of the arm, and in this way the linear rotation of the counter will give quantities proportional to the absorption coefficient.