Circuit arrangement for energizing a direct-current electromagnet

Claim 1

A CIRCUIT ARRANGEMENT FOR ENERGIZING AN ELECTROMAGNET, COMPRISING: A FULL-WAVE RECTIFIER BRIDGE PROVIDED WITH FOUR RECTIFIER ARMS, A PAIR OF DIAGONALLY OPPOSITE INPUT TERMINALS CONNECTABLE ACROSS A SOURCE OF ALTERNATING CURRENT, AND A PAIR OF DIAGONALLY OPPOSITE OUTPUT TERMINALS CONNECTED ACROSS SAID ELECTROMAGNET; A PAIR OF BREAK CONTACTS RESPECTIVELY INSERTED IN CIRCUIT WITH SAID OUTPUT TERMINALS AND RESPECTIVE RECTIFIER ARMS CONNECTED TO DIFFERENT INPUT TERMINALS; MEANS FOR OPENING BOTH SAID BREAK CONTACTS UPON ENERGIZATION OF SAID ELECTROMAGNET BY THE DIRECT-CURRENT OUTPUT OF SAID BRIDGE WHEREBY A PULSATING HOLDING CURRENT FOR SAID ELECTROMAGNET IS CAUSED TO PASS THROUGH TWO OF SAID ARMS IN SERIES WITH SAID ELECTROMAGNET; AND RESISTANCE MEANS SHUNTING ONE OF SAID BREAK CONTACTS AND ESTABLISHING A CIRCUIT INDEPENDENT OF SAID SOURCE THROUGH ONE OF THE TWO LAST-MENTIONED ARMS AND A THIRD OF SAID ARMS IN SERIES WITH SAID RESISTANCE MEANS AND SAID ELECTROMAGNET FOR MAINTAINING AN INDUCTIVE CURRENT FLOW THERETHROUGH BETWEEN PULSATIONS OF SAID HOLDING CURRENT.