The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 31, 1993
Filed:
Jan. 06, 1992
James E Burke, Villa Park, IL (US);
Salvatore G Perno, Winfield, IL (US);
Picker International, Inc., Highland Heights, OH (US);
Abstract
An anode (A) closes one end of an evacuated envelope (C) and a cathode end plate (22) closes the other. A cathode assembly (B) is mounted on a bearing (40) in the evacuated envelope such that the envelope and cathode can undergo relative rotation. A motor (38) rotates the anode and envelope while a pair of magnets (44, 46) hold the cathode assembly stationary. Bearing (40) functions as a current path from a current source (72) to the primary windings of a transformer (58). Another bearing (94) provides a return current path from the transformer to the current source. The secondary windings of the transformer are connected with a cathode filament (52). The transformer enables a relatively low ampere current to pass through the bearings to limit cathodic damage to the bearings, yet provides sufficient amperage to the filament to cause thermionic emission. The bearings provide a direct transfer of current which does not degrade the vacuum in the envelope in such a manner that the current through the cathode filament can be measured directly from outside the envelope.