High current square wave power source

Abstract

Abstract A SQUARE WAVE POWER SUPPLY USED IN PRESSURE SEAM WELDING OF AN BODIES. PHOTOELECTRIC CELLS DETECT THE PRESENCE AND LOCATION OF CAN BODIES PASSING BETWEEN PRESSURE ROLLER ELECTRODES TO ACTUATE SOLID STATE SWITCHES. A THREE PHASE A.C. SOURCE IS RECTIFIED AND FILTERED TO PRODUCE A SOURCE OF DIRECT CURRENT. AN OUTPUT TRANSFORMER AND A FIRST SCR ARE CONNECTED IN SERIES ACROSS THE DIRECT CURRENT SOURCE. CONNECTION OF THE OUTPUT TRANSFORMER WITH THE DIRECT CURRENT SOURCE IS CONTROLLED BY TWO TIMING CIRCUITS, ONE OF WHICH CONTROLS THE CONDUCTION DURATION OF THE FIRST SCR AND THE SECOND OF WHICH CONTROLS THE BLOCKING DURATION OF THE SCR. CONDUCTION OF THE SCR IS TERMINATED BY A POSITIVE QUENCHING THEREOF THROUGH THE APPLICATION OF A VOLTAGE ACROSS THE SCR GREATER THAN AND IN OPPOSITION TO THE VOLTAGE OUTPUT FROM THE DIRECT CURRENT SOURCE. A SUBSTANTIALLY WELL DEFINED AND CONSISTENT SQUARE WAVE OUTPUT IS PROVIDED BY PULSE-SHAPING CIRCUIT ELEMENTS IN COOPERATION WITH THE OUTPUT TRANSFORMER AND SCR AND BY ESTABLISHMENT OF A PRELIMINARY FLUX LEVEL IN THE OUTPUT TRANSFORMER PRIOR TO THE INITIATION OF AND UPON TERMINATION OF A TRAIN OF SQUARE WAVE OUTPUT CURRENT SIGNALS. AN OVERLOAD TIMING CIRCUIT PROTECTS THE SUPPLY BY TERMINATING THE INPUT THERETO.

Inventors

• 👤 Carl A Pesce
• 👤 Ernest M Gore
• 👤 James P Tatham

Bibliographic Details