Magnetic latch device for a clapper type contactor

Claim 2

A magnetic latch circuit for a clapper type contactor having a frame and activated by an electromagnetic coil in which the electromagnetic system of the contactor includes an operating coil having a coil core, a magnet frame connected to said operating coil and supporting the coil, and an armature, the improvement comprising: a contact arm pivotally mounted on said frame; a pair of contact tips, one stationarily mounted to the frame and the other movably associated with said contact arm, said contact arm having said armature fixedly connected thereto and depending therefrom so that when the armature moves to its closed position against the coil core the contact arm pivots likewise to break open the contact tips; and means, secured to said contact arm and pivoted therewith and abutting against the magnet frame at one end thereof and closely adjacent the heel of the armature at the other end thereof, for establishing a magnetic latch by a flux path from said magnet frame to said armature so that the establishing means latches the contact arm to a fixed position which retards the movement of the armature until the magnetic force in the coil builds to a level that will carry the armature through its complete motion without hesitation.

Claim 3

The magnetic latch circuit of claim 1 wherein the establishing means is stamped out of a single piece of carbon steel.

Claim 4

A magnetic latch circuit for a clapper type contactor having a frame and activated by an electromagnetic coil in which the electromagnetic system of the contactor includes an operating coil having a coil core, a magnet frame connected to the operating coil and supporting the coil, an armature, said contactor further including a contact arm pivotally mounted on the frame, a pair of contact tips, one associated with the contact arm and the other stationarily mounted on the frame, said armature fixedly mounted on said contact arm and depending therefrom so that the contact arm and armature move in unison, the improvement comprising: a substantially flat plate of a predetermined width and thickness to carry the optimum amount of magnetic flux; a depending transition section attached at one end of the plate having generally the same cross-section as the plate; a stop section attached to the other end of the transition section for abutting against the magnet frame, said stop section in a plane lower than said plate but generally parallel thereto; and an ear extending upwardly from said stop section and connected thereto for attachment to the contact arm so that the flat plate, transition section and stop section define a magnetic latch by establishing a flux path from the magnet frame which the stop section abuts against to the armature which the other end of the plate is closely adjacent thereto in order to latch the contact arm to a fixed position which retards the movement of the armature until the magnetic force in the coil builds to a level that will carry the armature through its complete motion without hesitation to clearly break the contact tips.

Claim 5

A magnetic latch circuit for a clapper type contactor having a frame and activated by an electromagnetic coil in which the electromagnetic system of the contactor includes an operating coil having a coil core, a magnet frame connected to the operating coil and supporting the coil, an armature, said contactor further including a contact arm pivotally mounted on the frame, a pair of contact tips, one associated with the contact arm and the other stationarily mounted on the frame, said armature fixedly mounted on said contact arm and depending therefrom so that the contact arm and armature move in unison, the improvement comprising: a substantially flat plate of a predetermined width and thickness to carry the optimum amount of magnetic flux; a depending transition section attached at one end of the plate having generally the same cross-section as the plate; a stop section attached to the other end of the transition section for abutting against the magnet frame, said stop section in a plane lower than said plate but generally parallel thereto; and an ear extending upwardly from said stop section and connected thereto for attachment to the contact arm so that the flat plate, transition section and stop section define a magnetic latch by establishing a flux path from the magnet frame which the stop section abuts against to the armature which the other end of the plate is closely adjacent thereto in order to latch the contact arm to a fixed position which retards the movement of the armature until the magnetic force in the coil builds to a level that will carry the armature through its complete motion without hesitation to clearly break the contact tips.