JPH07106641A - Ring integrated thermoelectric conversion element and apparatus using the same - Google Patents

Abstract

(57) [Abstract] [Purpose] Practical use of thermoelectric conversion elements that utilize the Peltier effect in industrial cooling equipment, air conditioning equipment for buildings, etc., to realize electronic cooling, and at the same time, achieve complete dechlorofluorocarbon. For that purpose 1. As a method of industrially producing a thermoelectric conversion device at a low cost and in large quantities, a thermoelectric conversion element integrally formed by powder metallurgy is created. 2. The thermoelectric conversion element module shape is an aggregate of ring-shaped sintered bodies. [Structure] Basically, a pair of modules in which ring-shaped N-type and P-type thermoelectric semiconductor elements are sandwiched between heat-resistant resin sheet rings, and a metal ring-shaped thin plate which is an electric conductor is provided inside and outside the ring. And a unit having a structure in which ceramics, which is an electrical insulator, is coated on the inner and outer peripheral surfaces of the above.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoelectric conversion device used in a cooling / heating device that electrically absorbs or radiates heat by utilizing the Peltier effect.

[0002]

2. Description of the Related Art Conventionally, a thermoelectric conversion module for converting heat into electricity or converting electricity into heat, as shown in the conventional example of FIG.
The basic structure is such that it has a structure in which the N-type semiconductor 13 or the P-type semiconductor 12 is sandwiched, a potential difference is applied to the metal plates on both sides, and a current is passed to cool the metal plates. The thermoelectric element N type semiconductor 13 or P type semiconductor used for this
As shown in FIG. 4, 12 had a structure in which several pairs or several hundred pairs or more were alternately arranged in series. Furthermore, FIG.
As shown in FIG. 5, the whole of a large number of these element aggregates was sandwiched between ceramic substrates 15 and 16 such as alumina.

[0003]

In such a conventional thermoelectric conversion device, a compound semiconductor element made of Bi, Te, or the like is used, and the manufacturing method is a melting method, a sintering method, or the like. A method of cutting and processing a bulk shaped body into a predetermined size has been used.

Further, as shown in FIG. 5, since the shape of the conventional thermoelectric conversion element has a planar structure, the shape of the contact portion with the heat conductor, which is the main purpose thereof, is also planar. In addition, in order to obtain the strength of the module itself and to maintain the insulation between the P-type semiconductor and the N-type semiconductor, a ceramic substrate made of plate-like alumina or the like has been used for packaging. For this reason, a large thermal resistance is generated between the heat conductor and the object to be cooled that are in contact with them, and it is difficult to heat and cool an object having a curved surface such as a cylindrical tube.

Further, in the structure of the conventional thermoelectric conversion device,
Since a compound semiconductor element made of Bi, Te, etc. is used, it is extremely fragile and easily damaged by the addition of mechanical stress such as bending or impact. It had the drawback that it could not be cooled.

When heating and cooling an object having a curved surface such as a cylindrical tube by using the thermoelectric module having the above structure, a method of soldering or crimping between the curved surface of the cylindrical tube and the thermoelectric element is considered. However, the loss due to Joule heat at the joint surface is large.

Further, even in a module having a structure adapted to the shape of an object to be cooled having a curved surface such as a cylindrical tube, a large number of finely cut and processed rectangular thermoelectric elements are formed of thin film metal or heat resistance. It had a structure attached to a flexible resin or the like. For this reason, it has a drawback that man-hours and yields are reduced.

Further, since expensive metal is used as the compound semiconductor element and these are finished to a predetermined size, the cutting process is repeated and a large amount of cutting margin is made, resulting in a high material cost.

[0009]

Based on the above problems, the present invention uses an element in which an N-type or P-type thermoelectric semiconductor is formed in a ring shape by a powder metallurgy sintering process. These are laminated by laminating plates or thin film electrical insulators such as nylon to each other, while electrical conductors such as Cu rings are formed on the inner and outer surfaces of the ring, and also Al2 which is a heat conductive material and an electrical insulating material. It has a structure in which coating films such as O3 and AlN are laminated. As described above, the present invention provides a ring-integrated thermoelectric conversion module having a structure in which a thermoelectric conversion module having a ring-integrated structure obtained by a powder sintering method is formed on the outer wall or inner wall surface of a cylindrical tube through which a fluid flows inside or outside. A conversion element and device are provided.

[0010]

Since the thermoelectric element of the present invention has a ring shape formed by the conventional general ceramics molding method,
By applying an electric potential to the thermoelectric conversion element, it is effective for cooling a cylindrical tube having a curved shape. That is, it is possible to cool or heat the fluid flowing in the tube by forming a ring-shaped thermoelectric conversion element on the outer wall surface of the tube having a curved surface in accordance with the dimension of the outer wall.

Further, unlike the conventional thermoelectric module, since it is not a structure of an assembly of a large number of finely cut and machined rectangular elements, the manufacturing process is shortened / reduced, and the man-hour yield is improved. It becomes easy to mass-produce industrially.

[0012]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows a state in which the ring-shaped thermoelectric conversion elements of the present invention are concentrically arranged in parallel. As the ring-shaped thermoelectric conversion element 1 of this example, one obtained by a normal powder sintering method or a hot isostatic method by which a higher density molded body was obtained was used. Dimensions and shape are outer diameter: 15 mmφ, inner diameter: 13
mmφ. These elements have the same inner diameter, outer diameter, and predetermined thickness for both N type and P type. As shown in FIG. 1, the N-type thermoelectric semiconductor ring elements 2 and the P-type thermoelectric semiconductor ring elements 3 are arranged in parallel on the same core with a predetermined interval alternately. Electrically good conductors such as the outer copper rings 4 are alternately attached to the outer peripheral portions of these two adjacent N-type thermoelectric semiconductor ring elements 2 and P-type thermoelectric semiconductor ring elements 3. Further, the same inner copper ring 6 is used for the inner peripheral portion to connect the inner peripheral portions of the adjacent rings in an electrically serial state. A thermoelectric device having the above-described set of ring-shaped thermoelectric conversion elements as a basic structure and continuously joined in parallel is fitted into a cylindrical water-cooling pipe described below, and heat for cooling and heat generation from the outer peripheral surface and the inner peripheral surface of the ring. Exchange.

FIG. 2 is a sectional view of a unit using an electric insulator in the combination of the electric conductor shown in FIG. 1 and the ring-shaped thermoelectric conversion element of the present invention. It has a structure in which ring-shaped electrical insulating materials 5 and 7 are inserted between adjacent N-type thermoelectric semiconductor ring elements 2 and P-type thermoelectric semiconductor rings 3. 12.5 to 15 mm as an electrically insulating material
A φ nylon ring was used.

FIG. 3 is an external view of a unit in which the ring-shaped thermoelectric conversion element according to the present invention is formed on the outer wall of an inner cylindrical tube 10 through which a fluid flows, and the outer cylindrical tube 8 is arranged outside them. A continuous ring-shaped thermoelectric conversion element is arranged in the gap between the body to be cooled and the outer tube and the inner tube corresponding to the heat radiation portion. Outer diameter with curved surface 12.7 mmφ
0.15 mm thick copper ring on the outside of the cylindrical tube, and the outer layer part is composed of a thin film coated with alumina by PVD method, and the outermost layer part has a copper ring of the same thickness and a thin film coated with alumina with an inner diameter of 15.08. It is closely attached to the inside of a cylindrical cylinder of mmφ. In this embodiment, the material of the ring-shaped thermoelectric conversion element is molded and heat-treated by an ordinary powder sintering method, but of course, other materials such as a ring made of a unidirectionally solidified single crystal by the conventional Bridgman method may be used. Even if it is used, the same effect can be obtained. Further, as the electric insulator material coated on the inner and outer circumferences of the ring, it is possible to use a material having a high thermal conductivity such as aluminum nitride other than alumina. Further, other than the nylon ring inserted in the gap of the thermoelectric element ring, another heat-resistant resin insulating material may be used.

FIG. 4 shows a perspective view of a conventional thermoelectric module.

FIG. 5 is an external view in which the thermoelectric element assembly of FIG. 1 is sandwiched on both sides by plates of a ceramic insulating material such as alumina.

[0017]

According to the present invention, it has been conventionally difficult to form a thermoelectric element on the outer wall surface of a tube having a curved surface. However, by using a ceramic element molded in a ring shape, the fluid flowing in the tube is cooled. Alternatively, it becomes possible to heat.

Further, since it is not the structure of a conventional assembly of a large number of minute elements cut and processed minutely, the manufacturing process is shortened / reduced, the man-hour yield is improved, and it is easy to mass-produce industrially. Become.

As described above, since the thermoelectric conversion module according to the present invention has a structure based on a ring-shaped integrated type element, it can be easily formed on the outer wall surface of a cylindrical cooling pipe which can flow inside. It is possible to simultaneously cool or heat the fluid inside the cylindrical tube.

[Brief description of drawings]

FIG. 1 is a ring-integrated thermoelectric converter according to the present invention.

FIG. 2 is a cross-sectional view of a ring-integrated thermoelectric device according to the present invention.

FIG. 3 is an external view of an air conditioning unit in which a ring-shaped thermoelectric conversion device according to the present invention is arranged outside a cylindrical pipe.

FIG. 4 is a perspective view of a conventional thermoelectric module.

FIG. 5 is an external view of a module in which a thermoelectric element assembly is sandwiched on both sides by plates of a ceramic insulating material such as alumina.

[Explanation of symbols]

 1 Thermoelectric conversion element 2 N-type semiconductor ring element 3 P-type semiconductor ring element 4 Outer copper ring 5 Nylon outer ring 6 Inner copper ring 7 Nylon inner ring 8 Outer cylindrical tube 9 Inner alumina coating film 10 Outer alumina coating 11 Inner cylindrical tube 12 P-type semiconductor element 13 N-type semiconductor element 14 Metal electrode 15 Alumina plate A 16 Alumina plate B 17 Solder A 18 Metal plate A 19 Metal plate B 20 Solder B 21 Square P-type semiconductor element 22 Square N-type semiconductor element

Claims (4)

[Claims] 1. A ring-integrated thermoelectric conversion element, characterized in that an N-type or P-type thermoelectric semiconductor that produces a Peltier effect is formed into a ring shape from a sintered body of powder metallurgy. 2. N-type and P-type thermoelectric semiconductors that produce a Peltier effect when a DC voltage is applied are formed into a ring shape, and these N-type and P-type thermoelectric semiconductors are alternately arranged, and a plate-like or thin-film shape is formed in between. The thermoelectric conversion device integrated with a ring, wherein the inner surface and the outer surface of the ring are alternately connected with a material having good electrical conductivity and are arranged concentrically in parallel with each other. 3. The ring-integrated thermoelectric element according to claim 2, wherein the outer peripheral portion and the inner peripheral portion of the N-type and P-type thermoelectric semiconductor rings are alternately connected in electrical series with a material having good electrical conductivity. Converter. 4. The ring-integrated thermoelectric conversion device according to claim 2, wherein the inside and / or the outside of the thermoelectric semiconductor ring is formed on an outer wall or an inner wall surface of a cooling pipe through which a fluid can flow.