Device for controlling the power for one or more electrons spinning used in an electron beam furnace

摘要

1,177,292. Automatic voltage and current control. AIR REDUCTION CO. Inc. April 3, 1967 [May 2, 1966], No. 15045/67. Heading G3R. A fraction of the voltage across an electron beam furnace is compared with an adjustable reference 84 and the error passed through an isolating circuit (even nos 90-98) to a transistor voltage regulator which normally supplies a positive bias to a grid 20 through a switch 22. When the voltage across a current sensing resistor 46 exceeds a level determined by a trigger circuit 24 switch 22 is opened and a negative cut off bias 112 is applied to the grid 20 through a resistor 110. After a delay determined by a circuit 114, switch 22 is reclosed. Electron beam current is controlled through a tranductor 122 having a power winding (not shown) a control winding 124 and winding 126 the output of which is compared with a reference 128, the difference between which controls the filament current through circuits 132, 134. The trigger circuit 24 is protected against excessive voltages by diodes 118, 120. The filament current may be alternatively controlled by evaporation rate or target temperature. The arrangement may be multiplied to supply a plurality of furnaces.