The Lincoln Electric Company

Denis Michael Osowski

Keith Leon Clark

Edward M Crouse

Scott Joseph Schraff

A method and system of controlling the output current/voltage characteristic curve of an engine driven alternator welder with a maximum open circuit output voltage, including a rotary engine, a three phase alternator, a rectifier bridge having a number of electronic switching devices for directing current to the output at an operating point determined by the firing angle of the switching devices, a sensor for sensing output current, a sensor for sensing output voltage, and a microprocessor output control device for controlling the firing angles of said switching devices in response to the sensed current and sensed voltage. The method and system comprise a device for creating a desired fixed slope operating current/voltage characteristic curve; an arrangement for sensing the present operating current/voltage point of the welder; and, a control for changing the firing angles of the switching devices to shift the current operating point to a new operating point on the desired, fixed slope current/voltage curve of the welder. Preferably, the switching devices include an SCR for each phase of the alternator.

Method and system for controlling the output of an engine driven welder

An engine-driven, multiple-phase, alternator-powered SCR rectified arc welding power supply using a single synchronizing winding within the alternator providing signals to a synchronizing digitizer which masks noise for most of each cycle of the alternator. The synchronizing circuitry prevents spurious synchronizing signals.

Growing community of inventors

Parma, OH, United States of America

Denis Michael Osowski