Multistep electronic cooler

• US 5,237,821 A
• Filed: 11/20/1991
• Issued: 08/24/1993
• Est. Priority Date: 08/20/1987
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Komatsu Seisakusho (Komatsu Ltd.)
• Original Assignee: Kabushiki Kaisha Komatsu Seisakusho (Komatsu Ltd.)
• Inventors: Okumura, Takuji, Yamashita, Masao
• Primary Examiner(s): Sollecito, John M.
• Application Number:
  US07/795,271
• Time in Patent Office: 643 Days
• Field of Search: 62/3.1, 62/3.2, 62/3.5, 62/3.6
• US Class Current: 62/3.2
• CPC Class Codes: F25B 21/02 using Peltier effect; using Nernst-Ettinghausen effect
• CPC Class Codes: H10N 19/101 Multiple thermocouples connected in a cascade arrangement

Abstract

A multistep electronic cooler developed for the purpose of minimizing the incoming heat quantity generated by convective heat transfer and radiant heat transfer with a simple structure and bringing the maximum achievable cooling temperature to a level lower than that in a conventional electronic cooler of this kind at a low cost. The multistep electronic cooler according to the present invention has a plurality of base plates (3) arranged as cooling plates in tiers within a vacuum container (5), a plurality of pairs of semiconductors (2) arranged between the base plates via a plurality of electrodes (4) bonded to the base plates, and one layer, at least, or more of heat shielding members (7a, 7b, 7c) covering spaces above the base plates (3). The surfaces of the parts assembled to form the multistep electronic cooler are coated with a substance having a low thermal emissivity, for example, gold.

Claims

1. A multistep electronic cooler housed within a vacuum container, comprising:

a plurality of thermoelectric elements stacked into multisteps;

a plurality of base plates serving as cooling plates and attached on the top ends of respective steps of said thermoelectric elements; and

a plurality of heat shield members arranged within said vacuum container and each of said heat shield members extending over at least one of said base plates for insulating the corresponding one of said base plate from external thermal load.

2. A multistep electronic cooler according to claim 1, wherein said heat shielding members are provided with heat reflecting members bonded to both inner and outer surfaces thereof.

3. A multistep electronic cooler according to claim 1, wherein each of said heat shielding members has a window hole made at the top portion thereof.

4. A multistep electronic cooler according to claim 1, wherein said heat shielding member is made of copper foil having a thickness of 12 μ

.

5. A multistep electronic cooler according to claim 2, wherein said heat reflecting member is made of gold foil having a thickness of 1 μ

.

6. A multistep electronic cooler according to claim 1, wherein surfaces of parts assembled to form said multistep electronic cooler are coated with a substance having a low thermal emissivity.

7. A multistep electronic cooler according to claim 6, wherein said substance having a low thermal emissivity is Au and the coating with Au is provided by one of adhesion, compression bonding, evaporation, and plating.

8. A multistep electronic cooler according to claim 1, wherein said vacuum container is made of a substance having a low thermal emissivity.

9. A multistep electronic cooler according to claim 8, wherein said substance having a low thermal emissivity is Au.

10. A multistep electronic cooler according to claim 1, wherein said vacuum container is coated with a substance having a low thermal emissivity.

11. A multistep electronic cooler according to claim 10, wherein said substance having a low thermal emissivity is Au and the coating with Au is provided by one of adhesion, compression bonding, evaporation, and plating .

12. A multistep electronic cooler housed within a vacuum chamber, comprising:

a plurality of thermoelectric elements stacked to form a plurality of steps of arrays, each of the arrays of said thermoelectric semiconductor elements being formed with at least one thermoelectric semiconductor element in such a manner that the lowermost array has the largest number of said thermoelectric semiconductor elements and the uppermost array has the smallest number to have at least one thermoelectric semiconductor element;

a plurality of base plates mounted on the tops of respective steps of said arrays of said thermoelectric semiconductor elements, said base plates serving as cooling plates for said electronic cooler, one of the base plates corresponding to said lowermost array of said thermoelectric semiconductor elements having the largest area and another one of the base plate corresponding to said uppermost array of said thermoelectric semiconductor elements having the smallest area; and

a plurality of head shield plates having different sizes to be piled one on the other in spaced part relationship to each other for covering at least one of said base plate.

13. A multistep electronic cooler housed within a vacuum chamber, comprising:

a plurality of thermoelectric semiconductor elements stacked to form a plurality of steps of arrays, each of the arrays of said thermoelectric semiconductor elements being formed with at least one thermoelectric semiconductor element in such a manner that the lowermost array has the largest number of said thermoelectric semiconductor elements and the uppermost array has the smallest number to have at least one thermoelectric semiconductor element;

a plurality of base plates mounted on the tops of respective steps of said arrays of said thermoelectric semiconductor elements, said base plates serving as cooling plates for said electronic cooler, one of the base plates corresponding to said lowermost array of said thermoelectric semiconductor elements having the largest area and another one of the base plate corresponding to said uppermost array of said thermoelectric semiconductor elements having the smallest area;

a plurality of head shield plates having different sizes to be piled one on the other in spaced apart relationship to each other for covering at least one of said base plate; and

a thermally reflective layer formed on either sides of each of said base plate.