Patent ID: 8248192

Claim:
A pulse activated magnetic trip/reset mechanism for a ground fault circuit interrupter, comprising: (i) a body having a top surface, an opposite, bottom surface, a cylindrical opening at the center; (ii) a ferrite core having a concave top surface, and a convex bottom surface, positioned inside of the cylindrical opening at the bottom of the body; (iii) a plunger having a top surface, a bottom surface and a body portion defined therebetween, the bottom surface having a corresponding convex shape matching the concave top surface of the ferrite core, wherein the plunger is positioned above the ferrite core in the cylindrical opening of the body, and is movable in two positions in reaction to a magnetic field surrounding the plunger: (1) a first position (trip position) where the plunger is in close contact with the ferrite core, and (2) a second position (reset position) where the plunger is away from the ferrite core; (iv) a ferrite surrounding formed of a single ferrite plate and adapted to surround an outer perimeter of the body to magnetically couple with the ferrite core and the plunger to form a complete magnetic field loop, wherein the body, and the ferrite core and the plunger positioned in the cylindrical opening of the body are received in the ferrite surrounding such that when the plunger is in its first position (trip position), the top surface of the plunger is away from a top end portion of the ferrite surrounding, and when the plunger is in its second position (reset position), the top surface of the plunger is in contact with the top end portion of the ferrite surrounding; (v) a permanent magnet positioned under the top surface of the body, around and outside of the cylindrical opening of the body; (vi) a trip/reset coil positioned at the bottom portion of the body and around the cylindrical opening of the body, wherein when a series of pulses in a first polarity pass through the trip/reset coil, the magnetic field generated by the trip/reset coil drives the plunger to the first position, and when a series of pulses in a second polarity that is opposite to the first polarity pass through the trip/reset coil, the magnetic field generated by the trip/reset coil drives the plunger to the second position; (vii) a reset spring received in the ferrite surrounding and positioned between a plunger block and the top surface of the body to keep the plunger in its reset position; (viii) a first fixed contact holder having a first fixed contact point; and (ix) a first movable contact holder having a first movable contact point, wherein the first movable contact holder is attached to the body portion of the plunger such that when the plunger is in its first position (trip position), the first movable contact point is not in contact with the first fixed contact point, and when the plunger is in its second position (reset position), the first movable contact point is in contact with the first fixed contact point.