Patent GB-800816-A (GB)
Title: Improvements in apparatus for recording values relating to a physical variable
IPC: G01D15/04
Filed: 1955-06-24
Abstract: 800,816. Selective punching-apparatus. ELECTRICITE DE FRANCE. June 24, 1955 [June 28, 1954], No. 18392/55. Class 31 (2). [Also in Groups XIX and XXXVIII] Apparatus for recording the variations of a physical variable at intervals of time T in the form of perforations on a displaceable band, comprises a coding counter unit adapted to be moved as a whole at the end of each interval of time T to perforate the band by means of punches, the resulting perforations representing the value registered by the counter. Apparatus suitable for recording electrical variables and capable of modification comprises measuring apparatus of electrodynamic type 1, 2, Fig. 1, for producing revolutions of a shaft representing the integral of the variable. According to the direction of rotation of the shaft, a finger 4 cooperates with a bi-polar contact device 5 to pass impulses through storage relays 7 to a " positive " or " negative " electromagnet 61 or 62 to drive a coding counter C in one sense or the other. The counter comprises three rollers R1, R2, R3 interconnected by transfer devices and each roller can occupy sixteen positions and has teeth d for representing four binary orders. At the end of every time interval T, a synchronous clock device H causes those punches 15 in a perforating device D which are selected and made effective by the teeth d to perforate the sheet 10 whose forward feed is also controlled by the device H. A record is thus produced in binary code of the integral or mean value of the variable in each interval T, the counter being zeroized after each recording. In a modification, the counter C comprises three ten-sided discs for units, tens and hundreds respectively and each bearing teeth for representing the first four binary orders. The discs are carried by a pivoted lever 35, Fig. 4, and are all depressed as a single unit by a cam 34 to cause selected punches 15 to perforate the sheet 10 according to the decimalbinary code. Punching, followed by zeroizing, is initiated at the end of every period T by the device H momentarily closing contacts 30 to energize relay 13 which in attracting its armature 42 withdraws a pawl 43 from locking engagement with a notch 44 in the cam 34 and closes contacts 41 to start a motor 40. The motor drives the shaft 37 carrying the cam 34 which in turn holds the contacts 41 closed till the pawl 43 again enters the notch 44 at the end of a complete revolution. So long as there is no failure of current, a relay 21 through its armature 22 holds a finger 63 on a resetting arm 64 between a projection 47 on the lever 35 and a validating punch 48 so that when recording takes place a hole is punched to indicate that the record is valid. If the current fails the finger 63 is withdrawn and the first record made after the current resumes will be made without a validating perforation, showing that the record is invalid, while, during its rotation, the cam 34 engages the arm 64 to reset the finger 63 for validating future records. Means are provided in another position for punching a hole or not according to whether the value is positive or negative. In apparatus suitable for recording the angular deflection of a pointer 49, Fig. 7, at the end of time intervals T, the device H causes impulses to be transmitted to the counter C while a follow-up pointer 55 travels from its origin to a position corresponding with that of the pointer 49 so that the number of pulses counted represents the instantaneous value of the angular deflection at the end of the period T. In another embodiment, a motor 60, Fig. 9, drives a feeler in appropriate direction over a potentiometer 59 to balance a voltage VI therefrom with a voltage V from a potentiometer 57 determined by the position of a pointer 49, a voltage comparator 58 controlling the motor 60 which drives through gear-box 61 the counter C so that its registration follows the variable continuously and when caused to perforate, records its instantaneous value.