GB457034A - Improvements in and relating to electro-magnetic interrupters - Google Patents

Abstract

457,034. Electromagnetic interrupters. MALLORY & CO., Inc., P. R., 3029, East Washington Street, Indianapolis, Indiana, U.S.A. March 14, 1935, No. 7965. Convention date, March 14, 1934. [Class 38 (v)] An electromagnetic interrupter which may be used as a potential changer comprises a yoke of permeable material, electromagnetic means associated with said yoke at one end, and a vibratory reed of magnetic material mounted on and magnetically connected to the other end of the yoke with circuit-making and breaking means associated with the reed, wherein the electromagnetic means comprises a single core member having a D.C. exciting winding, said core member being connected at its inner end to one end of said yoke and having its outer end facing the other end of the yoke, the major portion of the body of the vibratory reed being disposed substantially parallel to the axis of the single core member with the free end of the reed extending towards the outer end of said core. As shown in Fig. 1, the armature consists of a vibrating reed 21 of magnetic material secured at its lower end between the arms 12 of an inverted U-shaped yoke and carrying on an off-set part of the upper end a magnetic plate armature 22. The winding 13 is secured on a core 15 secured to the cross limb of the core and a lateral extension 20<1> of the end 20 of one of the limbs of the voke makes contact with the lower end of the reed to complete the magnetic circuit through the reed. The reed bears two pairs of contacts 23, 24, on opposite sides, Fig. 3, adapted to engage contacts on pairs of relatively fixed spring blades 26 and 28, 29 mounted at opposite sides of the reed. The free ends of the fixed contact springs are forked and engage the insulated ends of adjusting stops 36 which are set so that the springs 26, 29 for the two halves of the primary circuit break before and make after the springs 25, 28 for the two halves of the secondary circuit. When the interrupter is switched into circuit the coil 13 is in series with one half of the primary winding so that reed is at once moved and when it closes the primary circuit the operating coil is short circuited. Thus vibration of the reed is maintained and the circuits of the two halves of the primary and secondary circuits are alternately made and broken. The interrupter is mounted within an earthed outer casing 62 lined with sound-insulating material 65, 66 the connections being made by means of plug members 43.. 47. Condensers 56, 59 shunt the primary interrupter contacts for sparking-preventing purposes.