Patent ID: 8351177
Filing Date: 2013-01-08
Classification: B66C,H01F

Abstract:
1. A magnet discharge apparatus for an electromagnet, said electromagnet being associated with a control system and power source that applies a DC or rectified AC voltage to the magnet in a “lift” direction, and then applies a DC or rectified AC voltage in the opposite, or “reverse”, direction and applies control signals at specific times and for specific durations to the discharge apparatus, such discharge apparatus being comprised of: a primary lift discharge circuit further comprised of a series combination of a first diode and a first electrically-controlled switching element, said first diode being in the reverse-biased direction during “lift”, and said series combination connected in parallel across the magnet; a primary reverse discharge circuit further comprised of a series combination of a second diode and a second electrically-controlled switching element, said second diode being in the reverse-biased direction during “reverse”, and said series combination connected in parallel across the magnet; a secondary lift discharge circuit; and a secondary reverse discharge circuit.