US Patent No. 10,919,649

LOW-POWER HALL THRUSTER WITH AN INTERNALLY MOUNTED LOW-CURRENT HOLLOW CATHODE


Patent No. 10,919,649
Issue Date February 16, 2021
Title Low-power Hall Thruster With An Internally Mounted Low-current Hollow Cathode
Inventorship Ryan W Conversano, Pasadena, CA (US)
Dan M Goebel, Pasadena, CA (US)
Ira Katz, Pasadena, CA (US)
Richard R Hofer, Pasadena, CA (US)
Assignee CALIFORNIA INSTITUTE OF TECHNOLOGY, Pasadena, CA (US)

Claim of US Patent No. 10,919,649

1. A Hall thruster comprising:a center axis oriented from an upstream section of the Hall thruster, the upstream section housing a back pole for a magnetic circuit and a supply line for a gas propellant, to a downstream section concentric with an azimuthally-symmetrical discharge chamber;
the magnetic circuit comprising a center core, the center core comprising a counter bored cathode bore formed within the center core;
the counter bored cathode bore extending along the center axis, the counter bored cathode bore comprising:
an upstream bore having an upstream bore diameter and an upstream bore length along the center axis;
a downstream bore having a downstream bore diameter greater than the upstream bore diameter and a downstream bore length along the center axis, wherein the downstream bore length is shorter than the upstream bore length and, wherein the downstream bore is a counterbore of the upstream bore;
an internally-mounted cathode placed within the cathode bore, the internally-mounted cathode comprising:
an upstream section having an upstream cathode diameter and an upstream cathode axial length, wherein the upstream cathode diameter is an outermost diameter of the upstream section;
a downstream section having a downstream cathode diameter greater than the upstream cathode diameter and a downstream cathode axial length shorter than the upstream cathode axial length, wherein the downstream cathode diameter is an outermost diameter of the downstream section;
wherein the downstream section is positioned within the counterbore, and the upstream section is positioned within the upstream bore.