JPH01127925A - Thermocouple - Google Patents

Abstract

PURPOSE:To provide a thermocouple which is hardly limited by the shape and material of a material to be measured of temp. by thermally spraying two kinds of metals onto the material to be measured of temp. in such a manner that part thereof comes into contact with said material. CONSTITUTION:Fine powder of alumina is plasma-thermally sprayed to the material 1 to be measured of temp. to form an insulating film 2 and thereafter a metallic masking plate 8 blanked to a prescribed shape is covered thereon. Fine powder of copper 3 is then plasma-thermally sprayed from above said plate. A metallic masking plate 9 blanked to a prescribed shape is thereafter coated thereon and fine powder of constantan 4 is plasma-thermally sprayed from above said plate so that the copper 3 and the constantan 4 overlap partly on each other. The fine powder of the alumina is again thermally sprayed from above the same to form a protective film 5. The thermocouple is tightly adhered directly to the material 1 and is hardly limited by the shape and material of the material to be measured of temp. if the thermocouple is constituted in such a manner.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application 1] The present invention relates to thermoelectric lamps, and more particularly to thermocouples used for measuring the temperature of heating appliances such as hotplates.

[Prior Art] Conventionally, thermocouples are made of round wire or strip wire. A type II metal wire with both ends joined by welding was used. When measuring temperature with this thermocouple, one contact of the thermocouple is crimped onto the object to be measured using a mechanical substitute such as a spring, or fixed with adhesive or a magnet.
They were directly embedded inside the object to be measured.

[Points to be solved by the invention] However, when measuring temperature using a conventional thermocouple, if it is crimped with a mechanical mechanism such as a spring, a temperature error occurs due to the crimping pressure, and the temperature being measured is The object must have a flat surface, making it difficult to measure the temperature on a rough surface. Furthermore, when fixing thermocouples using adhesive, there are limits to the heat resistance and durability of the adhesive, making it difficult to measure high temperatures.
Furthermore, the adhesion work was often time-consuming, as it took time for the adhesive to solidify at the same time. Further, when a thermocouple is fixed using a magnet, the material of the object to be measured is limited, and it is difficult to fix the thermocouple to a non-metallic material. Furthermore, when a thermocouple is directly embedded inside an object to be temperature measured, the object to be temperature measured must be a cast product or something that can be cast, and even when the thermocouple is embedded, there is a risk that the shape of the object to be temperature measured may be restricted.

[Object of the Invention] The present invention has been made to solve the above-mentioned problem α, and its first purpose is to provide a thermocouple that is not easily restricted by the shape and material of the object to be measured. The second objective is to provide an inexpensive thermocouple that has good adhesion to the object to be measured and has small measurement errors.

[Means for solving α J In order to achieve this objective, the thermocouple of the present invention is characterized in that two types of metals are sprayed onto the temperature measured object so that a portion of the metal is in contact with the object. .

[Function] In the present invention having the above configuration, the thermocouple is in close contact with the object to be measured, and the temperature changes following the temperature change of the object to be measured. The thermoelectric lamp generates a potential difference according to its temperature change.

[Example 1] Hereinafter, an example embodying the present invention will be described with reference to FIGS. 1, 3, 4, and 5. Figure 1 is a cross-sectional view of an example of PJSl, in which alumina with a particle size of 5 to 25 μm is plasma sprayed onto a temperature measurement object 1 made of aluminum or steel such as a hot plate or iron, and electrically insulated with a film thickness of 80 μm. After creating the film 2, as shown in Fig. 3, it is covered with a masking plate 8 made of 1TT metal which has been hollowed out into a predetermined shape, and a shell 3 corresponding to F51 metal with a grain size of 5 to 25 μm is placed over the masking plate 8. As shown in Fig. 4, a metal masking plate 9 cut into a predetermined shape is covered with a metal masking plate 9, and then a funstantan 4 corresponding to the second metal having a particle size of 5 to 25 μm is plasma sprayed on top of the masking plate 9. do. However, at this time, as shown in FIG. 5, the copper 3 and the funstantan 4 are thermally sprayed with their parts overlapped. Fine alumina powder is again sprayed onto the thermocouple thus prepared to form a J-retaining film 5 of 80 μl.

In this thermocouple prepared as described above, a thermoelectromotive force measuring device 10 is connected to the end of the thermocouple as shown in FIG. 6, and the temperature is GFW'd and outputted from the thermoelectromotive force generated.

Further, when the temperature measurement object 6 is made of a non-metal such as ceramics, as shown in Fig. fjS2, there is no need for an electrically insulating coating between the temperature measurement object 6 and the thermocouple, resulting in a simpler structure.

[Effects of the Invention] As is clear from the detailed description above, the thermocouple of the present invention is inexpensive and adapts to the shape and material of the object to be temperature measured because the thermocouple is directly attached to the object to be measured by thermal spraying. It is less subject to restrictions and has smaller measurement errors.

[Brief explanation of the drawing]

1 to 6 show embodiments embodying the present invention. FIG. 1 is a sectional view of the main part of the embodiment, and FIG.
The figure shows a modification when the object to be measured is a non-metallic material, Figure 3 shows a thermal spraying state using a masking plate, and Figure 4 shows a thermal spraying process using a masking plate. FIG. 5 is a diagram showing a state in which a thermocouple is attached, and FIG. 6 is a diagram showing a temperature measuring device. 1... Temperature measurement object, 3... Cylinder, 4... Funstantan. Patent applicant Katsuji Kawanari, President and Director of Brother Industries, Ltd. Figure 1 Figure 2 Inasa 3 (2) Foil. □

Claims (1)

[Claims] 1. A first metal coating (3) sprayed onto the object to be measured (1), and a second metal coating (3) sprayed so as to be partially in contact with the first metal coating (3). 2. A thermocouple comprising a metal film (4).