GB764261A - Improved electromagnetic mercury relay of the impulse type - Google Patents

Abstract

764,261. Electromagnetic relays. INRECO AKTIEBOLAG. Jan. 31, 1955 [Feb. 4, 1954], No. 2883/55. Class 38(5) A relay having contacts which are opened and closed upon successive current impulses comprises a glass bulb 1 containing two mercury pools 2, 3 separated by a ridge 4, electrodes 9, 10 entering the pools respectively, and the electrode 9 forming a spindle for a U-shaped armature 11 and an insulating contact carrier 12. A lug 13 on the carrier 12 extends through an arc-like window 14 formed in one side limb of the armature, and when the electromagnet 5 is not energized the parts 11, 12 rest on the ridge 4, Fig. 3. The core 5a of the electromagnet 5 has two curved pole pieces 6, 7 embracing the bulb 1, and when the magnet is energized the armature 11 turns through 90 degrees to be opposite the pole pieces 6, 7 and an end of the window 14 knocks against the lug 13 to rotate the carrier 12 over its upper dead-centre position, and the parts assume the position shown in Fig. 4. During this movement of the carrier a U-shaped contact 15 thereon leaves the pools 2, 3 to break the circuit. On de-energization of the magnet the carrier lug 13 moves the armature clockwise so that the parts again rest on the ridge 4 in a position displaced 180 degrees from that of Fig. 3 The next current impulse causes a similar sequence of operations to return the contact 15 to its original position in which it bridges the pools 2, 3. In a modification the window 14 is provided on the carrier 12 and the lug 13 on the armature.