JPS588153B2 - Thermopile and its manufacturing method - Google Patents

Description

[Detailed description of the invention] In differential thermal analysis, differential scanning calorimetry, etc., -150
It is necessary to measure the temperature difference between a sample and a standard sample with high sensitivity over a wide range of temperatures ranging from °C to about +800 °C.

Although a thermopile can be used for this purpose, a conventional thermopile for differential temperature measurement has been constructed as shown in FIG.

That is, by alternately arranging the wires P and Q formed of each of a pair of thermocouple materials, connecting them in series, and bending them in a zigzag pattern, every other connection part p and q can be connected as a group in the vicinity. It was placed in

However, in such a thermopile, two wires P and Q extend in the same direction from one connection p or q, and in order to reduce thermal noise and perform high-precision measurements, the above-mentioned method is required. Since the strands cannot be made very thin, especially when performing thermal analysis as described above on a minute amount of sample, the number of connections, or contacts, that can be attached to the sample is limited, making it impossible to obtain high sensitivity. There were drawbacks.

Therefore, the present invention provides a thermopile capable of forming a very large number of contacts in a narrow area, and a method for easily manufacturing the thermopile.

Fig. 2 is a plan view of the embodiment of the present invention, and Fig. 3 is A-A in Fig. 2.
In the cross-sectional view A, a plurality of strip-shaped wires 2, 2, 3, and 3 each made of a pair of thermocouple materials are attached to the surface of a base plate 1 made of a thermal and electrical insulator such as alumina. 3...
A thermopile is formed by pasting ... with an adhesive or the like.

That is, strands 2, 2... and 3, 3...
are arranged alternately and connected in series, and every other connection part 4
, 4, . . . and 5, 5, .

Terminal parts 6 and 7 are provided at the inner and outer ends of the spiral, and if necessary, the strand 2 has a terminal part 7 as shown in the figure.
A terminal portion 8 is also provided on the wire 3 directly connected to the wire 3 .

Note that the connection parts 4, 4... and 5, 5...
・It is necessary to make this number equal.

When such a thermopile is used, for example, for differential thermal analysis, the connection parts 4, 4, and
. . . and 5, 5 . Parts 6 and 7
Detect the voltage between.

That is, between the terminals 6 and 7, there are connecting parts 4, 4, . . . between the thermocouple wires 2 and 3, and connecting parts 5, 5, .
... are connected alternately and in series in the same number, and the sample container and the standard sample container are connected to the connecting portions 4, 4, and 5, 5, respectively. are in contact with.

Therefore, the connection parts 4, 4... and 5, 5...
Let n be the number of..., then n of the thermocouple output obtained by the temperature difference between the sample container and the standard sample container.
A double output voltage is generated between terminals 6 and 7.

Furthermore, the temperature of the sample container can be determined by guiding the terminal parts 7 and 8 to a reference temperature part using conductive wires made of the same thermocouple material as these and detecting the output voltage therebetween.

Note that when manufacturing a thermopile as described above, first, each of a pair of thermocouple materials is made to a thickness of 0.02 m, for example.
A rectangular thin plate of about m is formed.

The thin plates 11 and 12 are 1 as shown by the chain lines in FIG.
The two straight edges are butted together so that they are in contact with each other, and the contact portions are welded by electron beam welding or other appropriate method to form a single material plate.

Next, by using an appropriate method such as photo-etching or electrical discharge machining, the spiral-shaped unnecessary portion 13 centered at a point C on the joining line of the material plates is removed and adhered to the surface of the base 1 with a heat-resistant adhesive. .

As described above with respect to the embodiments, the thermopile of the present invention has a pair of strands extending in opposite directions from one connection portion, that is, a thermocouple contact.

Therefore, when the width of the wire is kept constant, the distance between the contacts can be made extremely small, and many contacts can be formed in a narrow range. can be detected with high sensitivity.

Further, if the number of contacts and the area occupied by the group of contacts are constant, the width of the wire can be increased, so that thermal disturbance noise can be reduced and highly accurate measurements can be performed.

In addition, since the thermopile has a planar shape, the heating furnace of the thermal analysis device can also be made smaller and have a smaller capacity.

Furthermore, since the thermopile can be manufactured very easily, for example by the method described above, and the thermopile is formed of a thermocouple material having an exactly predetermined composition, a constant thermoelectromotive force characteristic can be obtained.

[Brief explanation of the drawing]

Figure 1 shows an example of the shape of a conventional thermopile.
FIG. 2 is a plan view of a thermopile according to an embodiment of the present invention, and FIG. 3 is a sectional view taken along line AA in FIG. In the figure, 1 is a base, 2 and 3 are wires of thermocouple material, 4 and 5 are connecting portions of the wires, and 6, 7, and 8 are terminal portions.

Claims (1)

[Claims] 1. A plurality of thermocouple strands made of each of a pair of thermocouple materials are connected in series so that the strands of each material are alternately arranged, and every other connection part is 1. A thermopile characterized in that the thermopiles are formed in a spiral shape on the surface of a thermal and electrical insulating base so that each thermopile is arranged close to each other as a group. 2. Two thin plates made of each of a pair of thermocouple materials are joined together at their linear edges to form one raw material plate, and then a spiral shape is formed around a point on the joining line of the raw material plates. A thermopile manufacturing method characterized in that a spiral thermopile in which a plurality of pairs of wires of strip thermocouple material are alternately connected in series is obtained by removing a part of the material plate.