Thermoelectric transducer, a manufacturing method thereof, a cooling device using the same, and a method for controlling the cooling device

• US 20050134167A1
• Filed: 01/27/2005
• Published: 06/23/2005
• Est. Priority Date: 10/07/2003
• Status: Active Grant

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Taomoto, Akira, Deguchi, Masahiro, Shibata, Motoshi, Ozaki, Toyokazu
• Granted Patent: US 7,003,962 B2
• Time in Patent Office: Days
• US Class Current: 313/491
• CPC Class Codes: F25B 2321/003 by using thermionic electron cooling effects
• CPC Class Codes: H10N 15/00 Thermoelectric devices without a junction of dissimilar materials; Thermomagnetic devices, e.g. using the Nernst-Ettingshausen effect integrated devices or assemblies of multiple devices H10N19/00

Abstract

A thermoelectric transducer comprising an emitter (1) for emitting electrons according to the action of heat or an electric field, a collector (2) disposed so as to face the emitter (1) and collect electrons emitted from the emitter (1), and an electron transport layer (3) held between the emitter (1) and the collector (2) to serve as a region for transferring the electrons emitted from the emitter (1), the electron transport layer (3) being a porous body having a mixed structure of a vapor phase and a solid phase, the entire solid phase which composes the porous body being composed of an insulating material, and the electrons emitted from the emitter traveling in the vapor phase by applying an electric potential to the collector (2) that is higher than that applied to the emitter (1).

Claims

1. A thermoelectric transducer comprising:

an emitter for emitting electrons;

a collector disposed so as to face the emitter and collect electrons emitted from the emitter; and

an electron transport layer held between the emitter and the collector;

the electron transport layer being a porous body having a structure in which a vapor phase and a solid phase coexist;

the entire solid phase being composed of an insulating material; and

the electrons emitted from the emitter being made to travel in the vapor phase by applying a higher electric potential to the collector than to the emitter.

2. A thermoelectric transducer according to claim 1, wherein the surfaces of the emitter and the electron transport layer contact each other.

3. A thermoelectric transducer according to claim 1, wherein the surfaces of the collector and the electron transport layer contact each other.

4. A thermoelectric transducer according to claim 1, wherein the surfaces of the emitter and the collector contact the electron transport layer.

5. A thermoelectric transducer according to claim 1, wherein the insulating material composing the porous body is a metal oxide.

6. A thermoelectric transducer according to claim 5, wherein the metal oxide is silica or alumina.

7. A thermoelectric transducer according to claim 1, wherein the insulating material contains at least one member selected from the group consisting of diamond, boron nitride and aluminium nitride.

8. A thermoelectric transducer according to claim 1, wherein the volume ratio of the solid phase is less than 15%.

9. A thermoelectric transducer according to claim 1, wherein the solid phase is formed by a plurality of particles connecting mutually, and the diameter of each particle is less than 20 nm and not less than 3 nm.

10. A thermoelectric transducer according to claim 1, wherein the emitter is formed from a material that comprises carbon as a main component.

11. A thermoelectric transducer according to claim 10, wherein the material comprising carbon as a main component contains a metallic element as an impurity.

12. A thermoelectric transducer according to claim 1, wherein the thickness of the electron transport layer is not less than 5 nm and not more than 500 nm.

13. A method for manufacturing a thermoelectric transducer, the thermoelectric transducer comprising:

an emitter for emitting electrons;

a collector disposed so as to face the emitter and collect electrons emitted from the emitter; and

an electron transport layer held between the emitter and the collector;

the electron transport layer being a porous body having a structure in which a vapor phase and a solid phase coexist;

the entire solid phase being composed of an insulating material; and

the electrons emitted from the emitter being made to travel in the vapor phase by applying a higher electric potential to the collector than to the emitter;

the method comprising a step of forming the porous body using a sol-gel reaction.

14. A cooling device comprising a thermoelectric transducer and a power supply:

the thermoelectric transducer having;

an emitter for emitting electrons;

a collector disposed so as to face the emitter and collect electrons emitted from the emitter; and

an electron transport layer held between the emitter and the collector;

the electron transport layer being a porous body having a structure in which a vapor phase and a solid phase coexist;

the entire solid phase being composed of an insulating material;

the electrons emitted from the emitter being made to travel in the vapor phase by applying a higher electric potential to the collector than to the emitter; and

the power supply for applying a voltage across the emitter and the collector in such a manner that an electric potential higher than that applied to the emitter is applied to the collector.

15. A cooling device comprising a thermoelectric transducer and a driving circuit:

the thermoelectric transducer having;

a plurality of emitters for emitting electrons;

a plurality of collectors for collecting electrons emitted from the emitters, the plurality of collectors being disposed so as to face each of the emitters; and

an electron transport layer held between the emitters and the collectors;

the electron transport layer being a porous body having a structure in which a vapor phase and a solid phase coexist;

the entire solid phase being composed of an insulating material;

the electrons emitted from the emitters being made to travel in the vapor phase by applying a higher electric potential to the collectors than to the emitters; and

the driving circuit applying a voltage to the emitters and the collectors.

16. A method for controlling a cooling device comprising a thermoelectric transducer and a driving circuit:

the thermoelectric transducer having;

a plurality of emitters for emitting electrons;

a plurality of collectors for collecting electrons emitted from the emitters, the plurality of collectors being disposed so as to face each of the emitters; and

an electron transport layer held between the emitters and the collectors;

the electron transport layer being a porous body having a structure in which a vapor phase and a solid phase coexist;

the entire solid phase that composes the porous body being composed of an insulating material;

the electrons emitted from the emitters being made to travel in the vapor phase by applying a higher electric potential to the collectors than to the emitters; and

the driving circuit applying a voltage to the emitters and the collectors;

the method comprising;

a step of making the plurality of emitters to thermally connect to a surface of an object to be cooled; and

a step of controlling the driving circuit so that a voltage is applied to each emitter and collector in such a manner that the cooling distribution formed by the plurality of emitters corresponds to the temperature distribution on the surface which is thermally connected to the plurality of emitters.

17. A method for controlling a cooling device according to claim 16, which further comprises a step of controlling the driving circuit so that a voltage is applied to the plurality of emitters and collectors except those in which a short-circuit occurs.