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US 5,676,873 AGranted
Microwave oven and magnetron with cold cathode
AssigneeSharp Kabushiki Kaisha
InventorsTakeo Takase, Masao Urayama, Terutaka Tokumaru, Minoru Makita, Seiki Yano
Life of this patent
Estimating the term…
Abstract
There is provided a magnetron comprising a cold cathode having an electron emitting member which is formed linearly or as a plane on a substrate to emit electrons a subdivided anode disposed oppositely in parallel with the electron emitting member, the subdivided anode having cavity resonators formed therein at the side of the cold cathode, and a magnet which producing a magnetic field lying at right angles to an electric field applied between the cold cathode and the subdivided anode. There is also provided a microwave oven for dielectric-heating a substance to be heated by using the magnetron as a microwave supply source.
Claims26
A magnetron, comprising:
- a generally planar substrate;
- a cold cathode having an electron emitting member for emitting electrons, said electron emitting member being formed in two coplanar dimensions on said substrate;
- a subdivided anode which is disposed oppositely in parallel with the electron emitting member and which has cavity resonators formed therein at the side of the cold cathode;
- and
- a magnet producing a magnetic field lying at right angles to an electric field applied between the cold cathode and the subdivided anode,
- wherein the length of the electron emitting member is 2.pi.mE/eB.sup.2 relative to the moving direction of the electrons emitted from the electron emitting member, wherein .pi. is the ratio of the circumference of a circle to its diameter, m is mass of an electron, E is an applied electric field, e is an amount of elementary electric charge, and B is a magnetic field.
3 more elements
A magnetron, comprising:
- a generally planar substrate;
- a cold cathode having an electron emitting member for emitting electrons, said electron emitting member being formed in two coplanar dimensions on said substrate;
- a subdivided anode which is disposed oppositely in parallel with the electron emitting member and which has cavity resonators formed therein at the side of the cold cathode;
- a magnet producing a magnetic field lying at right angles to an electric field applied between the cold cathode and the subdivided anode;
- and
- means for adjusting output power by adjusting the amount of electrons emitted from the electron emitting member.
3 more elements
A magnetron, comprising:
- a cold cathode having an electron emitting member, for emitting electrons, the electron emitting member being composed of a field-emission cold cathode array;
- a subdivided anode concentrically disposed around the periphery of the cold cathode;
- and
- a magnet producing a magnetic field, the magnetic field lying at right angles to an electric field applied between the cold cathode and the subdivided anode,
- wherein the length of the electron emitting member is 2.pi.mE/eB.sup.2 relative to the moving direction of the electrons emitted from the electron emitting member, wherein .pi. is the ratio of the circumference of a circle to its diameter, m is mass of an electron, E is an applied electric field, e is an amount of elementary electric charge, and B is a magnetic field.
2 more elements
A magnetron, comprising:
- a cold cathode having an electron emitting member, for emitting electrons, the electron emitting member being composed of a field-emission cold cathode array;
- a subdivided anode concentrically disposed around the periphery of the cold cathode;
- and
- a magnet producing a magnetic field, the magnetic field lying at right angles to an electric field applied between the cold cathode and the subdivided anode,
- wherein the electron emitting member is divided into two or more sections, and the sections of the electron emitting member are independently controlled to change their respective output power.
2 more elements
A microwave oven for dielectric-heating a substance placed in a heating room of the oven, comprising:
- a magnetron including a planar cold cathode having an electron emitting member for emitting electrons;
- a subdivided anode disposed oppositely and parallel with the electron emitting member, the subdivided anode having cavity resonators formed therein at the side of the cold cathode;
- and
- a magnet producing a magnetic field, the magnetic field lying at right angles to an electric field applied between the cold cathode and the subdivided anode;
- a gate electrode formed between the cold cathode and the subdivided anode of the magnetron;
- and
- means for changing microwave output power by varying a gate voltage applied to the gate electrode.
4 more elements
A microwave oven for dielectric-heating a substance placed in a heating room of the oven, comprising:
- a magnetron including a planar cold cathode having an electron emitting member for emitting electrons;
- a subdivided anode disposed oppositely and parallel with the electron emitting member, the subdivided anode having cavity resonators formed therein at the side of the cold cathode;
- and
- a magnet producing a magnetic field, the magnetic field lying at right angles to an electric field applied between the cold cathode and the subdivided anode,
- wherein the magnetron is equipped to a heating room housing through an electrode of the magnetron, the electrode being electrically insulated against the heating room housing, and a direct current power source which is not insulated against a commercial power source serves as a supply source of the magnetron.
2 more elements
A magnetron, comprising:
- a generally planar substrate;
- p1 a cold cathode having an electron emitting member for emitting electrons, said electron emitting member being formed in two coplanar dimensions on said substrate;
- a subdivided anode which is disposed oppositely in parallel with the electron emitting member and which has cavity resonators formed therein at the side of the cold cathode;
- and
- a magnet producing a magnetic field lying at right angles to an electric field applied between the cold cathode and the subdivided anode,
- wherein the length of the electron emitting member is less than 2.pi.mE/eB.sup.2 relative to the moving direction of the electrons emitted from the electron emitting member, wherein .pi. is the ratio of the circumference of a circle to its diameter, m is mass of an electron, E is an applied electric field, e is an amount of elementary electric charge, and B is a magnetic field.
3 more elements
A magnetron, comprising:
- a cold cathode having an electron emitting member, for emitting electrons, the electron emitting member being composed of a field-emission cold cathode array;
- a subdivided anode concentrically disposed around the periphery of the cold cathode;
- and
- a magnet producing a magnetic field, the magnetic field lying at right angles to an electric field applied between the cold cathode and the subdivided anode,
- wherein the length of the electron emitting member is less than 2.pi.mE/eB.sup.2 relative to the moving direction of the electrons emitted from the electron emitting member, wherein .pi. is the ratio of the circumference of a circle to its diameter, m is mass of an electron, E is an applied electric field, e is an amount of elementary electric charge, and B is a magnetic field.
2 more elements
Dependencies are inferred from the claim text.