Patent GB-215768-A (GB)
Title: Improvements in and relating to recording devices for use in measuring instruments and more particularly electric meters
IPC: G01R13/04
Filed: 1924-05-07
Abstract: 215,768. Landis et Gyr Soc. Anon. May 7, 1923, [Convention date]. Recording by distinctive marks.-In intermittently recording apparatus particularly for use in electricity measuring instruments the recording element is moved unidirectionally with reference to the record-band by the instrument and the recording is effected by a periodically controlled power device independent of the available power of the moving element of the instrument. In the form shown in Fig. 1 the recording stylus 23 is carried on an arm 24 integral with a piston 24<11> freely movable in a slotted tube 18 and connected at its ends to a cord 22 passing over pulleys 20, 21. The spindle of the pulley 21 supports a crown wheel 27 with which engages a pinion 29 connected through the shaft and friction clutch 31 with a worm wheel 32 in gear with a worm 33 on the indicating shaft of the measuring instrument and adapted to move the stylus in the direction of the arrow 34 during the measuring period. At the end of this period a clock driven cam 1 releases a lever 2 so that a pawl 4 carried thereby advances a ratchet wheel 5 to release a bell crank lever 14 from engagement with one of series of pins 13 mounted on the wheel 5. The lever 14 is under the control of an arm 17 extending from the tube 18, contact between the lever and arm being maintained by a spring 19. Movement of the lever 14 through a pin 15 thereon effects the closure of a pair of contacts 16 in the circuit of an electric motor 12 which thereupon drives a shaft 10. Rotation of the shaft 10, through a mutilated toothed wheel 30 thereon, effects the rotation of a gear wheel 28 meshing with the crown wheel 27 and adapted to drive it in the opposite, direction to that produced by the pinion 29 so that the stylus, which has been pressed into contact with the recordband 25 by the rocking of the lever 14, produces a record as it is returned to its zero position. A suitable stop and spring coupling co-operating with the pulley 21 may be provided to arrest the stylus at its initial position. At the end of one revolution of the shaft 10 a cam 9 thereon permits a lever 7 to drop so that a pawl 6 on lever may advance the ratchet wheel 5 until the succeeding pin 13 engages and restores the bell crank lever 14 so as to interrupt the motor circuit whereupon the stylus is again moved bv the measuring instrument. The record-band 25 is preferably of translucent paper beneath which is arranged a transfer paper band both being wound on a clock driven roller 26. A brake actuated by the lever 14 may be provided to arrest the motor 12. In the form shown in Fig. 2, two change over switches 42, 43 are provided in the motor circuit. The switch 42 co-operates with twc levers 38, 39 and a double clock actuated cam 36, 37 and the switch 43 is controlled by a pin 44 on a wheel 45 connected with the motor driven shaft 48. During the measuring period the lower contact of the switch 42 and the upper contact of the switch 43 are open and the circuit of the motor is broken. At the end of this period the lower contact of the switch 42 is closed bv the movement of the lever 3R and the motor causes the shaft 48 to rotate and so effect the return movement of the stylus 23<1>. A rotation of the shaft 48 through the pin 44 opens the lower contact of the switch 43 to stop the motor.