US Patent 4,650,631
United States Patent and Trademark Office
University of Iowa Research Foundation (Iowa City, IA, US)
A container device for a fusion plasma which has a beam of charged particles accelerating system feeding an ion or plasma beam into a polytron magnetic device. The polytron is formed from a succession of magnetic cusps joined point to point around a torus. The accelerating system introduces an ion or plasma beam into the polytron through a magnetic junction. A second accelerating system may introduce a second beam of different velocity creating an instability and turbulent mixing of the two beams, which are favorable for a fusion reaction.
Knorr, George E. Injection, containment and heating device for fusion plasmas. US Patent 4,650,631 filed May 14, 1984 and issued March 17, 1987. https://ir.uiowa.edu/patents/50