GB619604A - Improvements relating to electric circuit breakers - Google Patents

Abstract

619,604. Automatic circuit-breakers. ROTAX, Ltd., and BOURNE, W. G. Dec. 16, 1946, No. 36982. [Class 38 (v)] A three-phase, solenoid-closed and overloadreleased circuit-breaker comprises contacts e on spring-loaded fingers f pivoted at g to an arm c pivoted at d to the frame a. Toggle links m, n pivoted to the arm c at q and at r to a lever s pivoted at t, have a joint pin p engaged by a slotted link w connected to the plunger v of the closing solenoid u. A tripping toggle 3, 4 pivoted at 8 to the lever s and at 7 to a fixture, is overset and held by a spring-blade 5, thereby normally locking the lever s. Energization of the solenoid u raises the link w to overset the toggle m, n and close the breaker, and a roller 2 on the pin p engages a spring- blade x to open contacts y, z, Fig. 2, and deenergize the solenoid, the plunger of which descends, leaving the toggle m, n set. Raising the pin 6 to break the toggle 3, 4 releases the lever s allowing the spring-blade x to move the toggle m, n over-centre and spring o then rocks the arm c to open the breaker. The pin 6 may be raised either by a spring-loaded, push-button actuated lever 9 pivoted at t, or by a stud 15 on a trip-lever 12 pivoted at 13 and actuated by the plunger 17 of a solenoid 16. The solenoid 16 may be energized either by a push-button switch or by closure of contacts 18, 19 by a lever 22 on an armature 24 actuated by overload windings 26 in series with the contacts. The spring 5 resets the toggle 3, 4 for the next closing operation.