Patent GB-229037-A (GB)
Title: Improvements in or relating to electric relays
IPC: H02H3/027
Filed: 1923-12-11
Abstract: 229,037. Ross, T. W., Ryder, C., and Metropolitan-Vickers Electrical Co., Ltd. Dec. 11, 1923. Induction motor relays; switches, actuating.- In time-lag relays of the kind in which a plurality of contact controlling devices are. adapted to be selectively actuated, usually against the action of re-setting springs, from a single motive element through respective clutches and speedreducing mechanism or other escapement devices providing the necessary time lags, the contact controlling devices are selectively actuated by an induction disc device supplied with alternating current. The induction disc motor 1 drives a shaft 13 by means of a non-magnetic disc 12 and electromagnets 14, 15 for use with alternating currents. Fig. 2 shows the connections, the magnet 14 having a main coil 16 with terminals 17, and a secondary coil 18 connected to the primary 19 of a saturated transformer 20, the secondary 21 of which is connected to a coil 22 of the magnet 15. By this arrangement rotation of the disc has an arithmetic, instead of a square, relation with the alternating current, and the setting of the motor may be varied by a fixed or variable resistance 23. The transformer 20 mav be omitted and the relation may be obtained by arranging for the magnet 14 to be saturated, and in some cases a relation other than arithmetical may be employed. The spindle 13 drives a shaft 26 through reduction gearing 24, 25, and the shaft 26 carries worms 27, 28 with which worm wheels 29, 30 may be brought into engagement. The latter are mounted on shafts 31 rotatable in frames 32, 33 which are pivoted on a shaft 34 and movable to effect this engagement upon the energization of magnets 10, 11 which have pivoted armatures 35 in connection with the frames 32, 33. The shafts 31 carry arms 5, 6, carrying contacts adapted to bridge contacts 2, 3, 4, and maintained by springs 37 in their "off" " position against adjustable stops 36 in the form of pegs adapted to engage one of a plurality of holes 42. Energization of the magnet 10 throws in the clutch 27, 29 so that the arm 5 rotates and bridges contacts 2 in connection with terminal 38, 39. Energization of magnet 11 causes the arm 6 to bridge the contacts 3, in connection with terminals 40, and after a wiping action to engage contacts 4 in connection with terminals 39, 41. The timeelement of both arms 5, 6 is variable by varying the torque on the disc 12. as by varying the value of the resistance 23. Fig. 3 shows a means of connecting up the device to mains 43 by means of switches 44, 45 of the two-pole, single throw type, whereby operation of either will connect up the coil 16 and the corresponding magnet 10 or 11, or both switches may be operated to connect up the coil 16 and both magnets 10, 11. Upon opening the switches, the motor stops, the clutches are thrown out. and the springs 37 reset the device. The arms 5. 6, instead of carrying bridging contacts, may be arranged to engage co-operating pairs of fixed contacts to close or open circuits. According to the Provisional Specification any type of motor may be used.