X-ray tube with ferrite core filament transformer

In an x-ray tube which includes an evacuated envelope, a cathode assembly and an anode surface disposed within the evacuated envelope, the cathode assembly including a thermionic cathode means which emits electrons in response to electrical stimulation, a means for permitting relative rotational movement between the cathode assembly and the envelope, and a high voltage means for creating a high potential between the anode and cathode assembly, the improvement comprising:

• a secondary winding with a ferrite core mounted to the cathode assembly within the evacuated envelope and held at substantially the potential thereof, the secondary winding being connected with the thermionic cathode means;
• a primary winding with a ferrite core disposed exterior to the evacuated envelope, the primary ferrite core being mounted across the envelope from and in a magnetic flux coupled relationship with the secondary ferrite core, the primary winding being at substantially the same potential as the secondary winding;
• and
• an isolating transformer for isolating the primary winding from an AC electric source.

A rotating anode x-ray tube comprising:

• an evacuated envelope having a vacuum in an interior thereof;
• an anode formed at least along an annular surface adjacent one end of the envelope;
• a cathode assembly rotatably supported by the envelope, the cathode assembly including a cathode means for emitting electrons in response to electrical stimulation;
• a means for rotating the envelope and anode;
• a means for holding the cathode assembly stationary as the envelope and anode rotate;
• a ferrite core transformer having (i) a primary winding and a C-shaped primary ferrite core exterior of the envelope, the primary ferrite core extending between end faces disposed contiguous to and conforming with an exterior surface of the envelope and (ii) and a secondary winding and a C-shaped secondary ferrite core extending between end faces disposed in the vacuum interior of the envelope, the primary and secondary core end faces being disposed sufficiently contiguous to each other that magnetic flux from the primary ferrite core is communicated to the secondary ferrite core, the secondary ferrite core, the secondary winding being connected with the cathode assembly for providing an AC electrical current path to the cathode assembly.

A rotating anode x-ray tube comprising:

• an evacuated envelope;
• an anode formed at least along an annular surface adjacent one end of the envelope;
• a cathode assembly rotatably supported by the envelope, the cathode assembly including a plurality of filaments for emitting electrons in response to electrical stimulation;
• a means for rotating the envelope and anode;
• a means for holding the cathode assembly stationary as the envelope and anode rotate;
• a ferrite core transformer having (i) a primary winding and a primary ferrite core exterior of the envelope and (ii) a plurality of secondary ferrite cores mounted to the cathode assembly in an interior of the envelope, each filament being connected with one of a plurality of secondary windings which each encircle one of the ferrite cores mounted to the cathode assembly inside the envelope.

A rotating anode x-ray tube comprising:

• an evacuated envelope;
• an anode formed at least along an annular surface adjacent one end of the envelope;
• a cathode assembly rotatably supported by the envelope, the cathode assembly including a cathode means for emitting electrons in response to electrical stimulation;
• a means for rotating the envelope and anode;
• a means for holding the cathode assembly stationary as the envelope and anode rotate;
• a primary winding and a primary ferrite core exterior of the envelope;
• a secondary ferrite core having at least one end face which conforms to an interior surface of the envelope in a close, magnetic flux coupled relationship with the primary ferrite core;
• a dielectric member surrounds at least a portion of the secondary ferrite core;
• a secondary winding including an insulation free wire wound around the dielectric member in a spiral path with spaced turns, the uninsulated wire being connected with the cathode assembly.

An x-ray tube comprising:

• an evacuated envelope having a circularly cylindrical side wall;
• an anode formed at least along an annular surface adjacent one end of the envelope;
• a cathode assembly rotatably supported relative to the envelope, the cathode assembly including a thermionic cathode means for emitting electrons in response to electrical stimulation;
• a transformer having:
• a primary winding encircling a C-shaped primary core exterior of the envelope, the primary core having end faces disposed contiguous to and conforming with an exterior surface of the envelope side wall,
• a secondary winding encircling a C-shaped secondary core interior to the envelope, the secondary core having end faces disposed contiguous to and conforming to an interior surface of the envelope side wall, the primary and secondary core end faces being disposed sufficiently contiguous to each other that magnetic flux from the primary core is communicated across the envelope side wall to the secondary core, the secondary winding being connected with the thermionic cathode means.

An x-ray tube comprising:

• an evacuated envelope;
• an anode formed at least along an annular surface adjacent one end of the envelope;
• a cathode assembly rotatably supported by the envelope, the cathode assembly including a thermionic cathode means for emitting electrons in response to electrical stimulation;
• a ferrite core transformer including:
• a primary winding encircling a primary ferrite core exterior of the envelope;
• a dielectric member surrounding at least a portion of a secondary ferrite core;
• and,
• a secondary winding including an insulation free wire wound around the dielectric member in a spiral path with spaced turns, the uninsulated wire being connected with the cathode means.

An x-ray tube comprising:

• an evacuated envelope;
• an anode formed at least along an annular surface adjacent one end of the envelope;
• a cathode assembly rotatably supported by the envelope, the cathode assembly including a thermionic cathode means for emitting electrons in response to electrical stimulation;
• a ferrite core transformer having a primary winding encircling a primary ferrite core exterior of the envelope and a secondary winding encircling a secondary ferrite core interior of the envelope, the primary ferrite core having a transverse cross-section which is larger than a transverse cross-section of the secondary ferrite core, the primary ferrite core having end faces disposed contiguous to and conforming with an exterior surface of the envelope, the secondary ferrite core extending between end faces which conform to an interior of the envelope, the primary and secondary ferrite core end faces being disposed sufficiently contiguous to each other that magnetic flux from the primary ferrite core is communicated to the secondary ferrite core, the secondary winding being connected with the thermionic cathode means.