The United States of America As Represented by the Administrator of the

Vincent K Rawlin

James S Sovey

Robert F Roman

Roger M Myers

A cathode in an MPD thruster has an internal heater and utilizes low work function material. The cathode is preheated to operating temperature, and then the thruster is fired by discharging a capacitor bank in a pulse forming network.

Pulsed mode cathode

An improved ion thruster (10) for low specific impulse operation in the 1500 sec to 6000 sec range has a multicusp boundary field (48) provided by high strength magnets (30-38) on an iron anode shell (14) which lengthens the paths of electrons from a hollow cathode assembly (20). A downstream anode pole piece in the form of an iron ring (40) supports a ring of magnets (44) to provide a more uniform beam profile. A cylindrical cathode magnet (46) can be moved selectively in an axial direction along a feed tube (22) to produce the desired magnetic field at the cathode tip (24).

Growing community of inventors

Wellington, OH, United States of America

Vincent K Rawlin