JP2017032406A - Structure and method for attaching thermo couple - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure for attaching a thermo couple using a reinforced platinum based thermo couple, capable of achieving the joining of a thermocouple having a high lifetime without causing strength degradation due to melting.SOLUTION: A structure 100 for attaching a thermocouple comprises: an instrument 1 formed using platinum, platinum alloy or oxide dispersion reinforced platinum; a reinforced platinum based thermocouple 11; and an attachment part 4 in which the temperature measurement contact 10 of the reinforced platinum based thermocouple 11 is fixed to a portion to be measured of the instrument. The reinforced platinum based thermocouple 11 has a high temperature strength having a rupture time of 100 hours or more when a stress of 10 MPa is applied at a temperature of 1100°C in the atmosphere; the diameter of the single wire of the reinforced platinum based thermocouple 11 is 0.1 mm or more and 2.0 mm or less; and the temperature measurement contact 10 is diffusion-joined.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a thermocouple mounting structure, and in particular, when using a reinforced platinum-based thermocouple to measure the temperature of a predetermined part of a tool formed using platinum, a platinum alloy or oxide dispersion-strengthened platinum, a disconnection trouble occurs. The present invention relates to a thermocouple mounting structure that is less prone to cause a problem.

  As a thermocouple using platinum, for example, an R thermocouple using a positive electrode (plus electrode) made of a platinum rhodium alloy (rhodium 13%) and a negative electrode made of pure platinum, and a positive electrode made of a platinum rhodium alloy ( There is an S thermocouple using a strand made of 10% rhodium and a strand made of pure platinum for the negative electrode.

  These thermocouples are used for temperature measurement of platinum glass melting devices. Then, after welding the tip of the thermocouple, use a platinum plate as a reinforcing material in the vicinity of the welded part, and place it so as to cover part of the strands of the thermocouple, and weld and fix the four corners of the platinum plate There is a disclosure of a thermocouple mounting structure (see, for example, Patent Document 1). Patent Document 1 describes that even if the tip of the thermocouple is directly welded and attached to the measurement site of the apparatus by this technique, disconnection of the thermocouple can be reliably prevented.

JP 2011-158424 A

  In the technique described in Patent Document 1, a thermocouple of Pt vs. Pt—Rh alloy is used for temperature measurement of a platinum glass melting furnace. However, this thermocouple has a problem that when it is used at a high temperature for a long time, it deteriorates and breaks, and this cannot be avoided.

  Therefore, in order to increase the strength of the thermocouple itself, a thermocouple having a higher strength than the conventional one called a reinforced platinum-based thermocouple has been developed. However, since it is a thermocouple in which inclusions are inserted into the thermocouple wires to improve the strength, there is a problem that when joining by melting, the strength is greatly deteriorated and cannot be used.

  Accordingly, an object of the present invention is to realize a long-life thermocouple junction without causing deterioration in strength due to melting in a thermocouple mounting structure using a reinforced platinum-based thermocouple.

  The inventors of the present invention have maintained the strength of the reinforced platinum thermocouple by bonding the temperature measuring contact by adopting diffusion bonding, that is, a thermal diffusion phenomenon, instead of the melting method as a bonding method of the reinforced platinum thermocouple. As a result, the present invention was completed. That is, the thermocouple mounting structure according to the present invention includes an instrument formed using platinum, a platinum alloy or oxide dispersion strengthened platinum, a reinforced platinum thermocouple, and a temperature measuring contact of the reinforced platinum thermocouple. A thermocouple mounting structure having a mounting portion fixed to a measurement target site of the instrument, wherein the reinforced platinum-based thermocouple has a fracture time of 100 hours when a stress of 10 MPa is applied at 1100 ° C. in the atmosphere. It has the above high-temperature strength, the wire diameter of the reinforced platinum-based thermocouple is 0.1 mm or more and 2.0 mm or less, and the temperature measuring contact is diffusion-bonded.

In the thermocouple mounting structure according to the present invention, the mounting portion has a chip made of a platinum-based material, and the temperature measuring contact is:
(1) Whether the positive electrode of the reinforced platinum-based thermocouple is diffusion bonded to the chip, the negative electrode is diffusion bonded to the chip, and the positive electrode and the negative electrode are not diffusion bonded.
(2) The positive electrode and the negative electrode of the reinforced platinum thermocouple are diffusion bonded, or
(3) The positive electrode of the reinforced platinum thermocouple is diffusion bonded to the chip, the negative electrode is diffusion bonded to the chip, and the positive electrode and the negative electrode are diffusion bonded. And it is preferable that it is fixed to the instrument in a state covered with the chip. Since the attachment portion has a structure with a chip, the temperature-measurement contact that is diffusion-bonded can be more firmly attached to the instrument.

  In the thermocouple mounting structure according to the present invention, the tip has a facing surface, the facing surface sandwiches a temperature measuring contact of the reinforced platinum thermocouple, and the tip is fixed to the instrument. It is preferable. Since the chip sandwiches the temperature measuring contact of the thermocouple, the thermocouple is mechanically and firmly attached to the chip. In addition, since the contact area between the tip and the instrument can be maximized, the tip can be more firmly attached to the instrument.

  In the thermocouple mounting structure according to the present invention, it is preferable that the chip has a slit shape, and the facing surface is an inner surface of the slit. The chip having such a structure facilitates the work of sandwiching the thermocouple element wire into the chip. Furthermore, since the faces facing each other are on one chip, they do not fall apart. Furthermore, when the chip is mechanically caulked, the slits are crushed, so that the thermocouple can be sandwiched with a stronger force.

  In the thermocouple mounting structure according to the present invention, it is preferable that the tip is diffusion bonded to the instrument. It does not cause strength deterioration of the joined part. In addition, it is possible to join the chip to the instrument at the same time as the work of diffusion bonding the temperature measuring contact.

  In the thermocouple mounting structure according to the present invention, a platinum foil having a thickness of 0.01 mm or more and 0.5 mm or less is sandwiched between the instrument and the chip, and the abutting surfaces are diffusion bonded. It is preferable that Since the platinum foil can fill the gap between the tool and the chip, the bonding strength can be increased.

  In the thermocouple mounting structure according to the present invention, a plate made of a platinum-based material having a thickness of 0.3 mm or more and 2.0 mm or less is sandwiched between the instrument and the chip, and the surfaces are in contact with each other It is preferable that they are diffusion-bonded together. Since the plate is inserted between the instrument and the tip, the strength of the attachment portion can be increased.

  In the thermocouple mounting structure according to the present invention, the plate is preferably diffusion bonded to the instrument. It does not cause strength deterioration of the joined part. In addition, it is possible to join the plate to the instrument simultaneously with the operation of diffusion bonding the temperature measuring contact.

  In the thermocouple mounting structure according to the present invention, a thickness of 0.01 mm or more and 0.5 mm or less is provided between the tip and the plate, or between the instrument and the plate, or both. It is preferable that the platinum foil is sandwiched and the surfaces that come into contact with each other are diffusion bonded. Since the platinum foil can fill a gap between the chip and the plate, or between the instrument and the plate, or both, the bonding strength can be increased.

  In the thermocouple mounting structure according to the present invention, it is preferable that at least one of the positive electrode and the negative electrode of the reinforced platinum thermocouple is diffusion bonded in a state of being wound around a platinum foil. Since the platinum foil can fill the gap around the strand of the thermocouple, the bonding strength can be increased.

  At least one of the positive electrode and the negative electrode of the reinforced platinum-based thermocouple according to the present invention contains a metal element or a gas element, or contains at least one of oxide, nitride, carbide, or boride. It is preferable to do. The strength of the reinforced platinum-based thermocouple wire is maintained without causing strength deterioration due to melting.

  In the thermocouple mounting structure according to the present invention, the instrument includes a glass melting line instrument, a glass melting furnace, a melting tank, a defoaming layer, a clarification tank, a stirring tank, or a connection pipe.

  The thermocouple mounting method according to the present invention is the thermocouple mounting method in the thermocouple mounting structure according to the present invention, wherein the portion to be the temperature measuring contact is mechanically joined and the portion is pressurized. It is characterized by having a step of diffusion bonding by heating to a temperature of 1000 ° C. or higher and thermally diffusing. The parts to be diffusion bonded can be bonded at one time, and the workability is excellent.

  According to the present invention, in a thermocouple mounting structure using a reinforced platinum-based thermocouple, a long-life thermocouple junction is realized without causing strength deterioration due to melting.

It is the schematic which shows the attachment state of the thermocouple which concerns on this embodiment, (a) is a top view, (b) is an AA cross section. It is the schematic which shows an example of a chip | tip, (a) is a front view, (b) is a right view, (c) is a rear view. It is the schematic which shows the attachment state of the thermocouple which concerns on another embodiment, (a) is a top view, (b) is a BB cross section, (c) is CC sectional drawing. It is the schematic which shows the example of a BB cross section, (a) is an example in which the positive electrode and negative electrode of a thermocouple are diffusion-bonded, (b) is the positive electrode of a thermocouple, diffusion-bonded with a chip | tip, and a negative electrode is a chip | tip. (C) The thermocouple positive electrode is diffusion bonded to the chip, the negative electrode is diffusion bonded to the chip, and the positive electrode and negative electrode are diffusion bonded. This is not an example. It is the schematic which shows another example of an AA cross section, and is an example which pinched platinum foil between the chip | tip and the instrument. It is the schematic which shows the other example of an AA cross section, and is the example which pinched | interposed the board | plate which consists of platinum-type materials between the chip | tip and the instrument. It is the schematic which shows the other example of an AA cross section, and is the example which pinched | interposed the board | plate which consists of platinum-type materials between the chip | tip and the instrument, and pinched platinum foil between them. It is the schematic which shows another example of an AA cross section, and is the example which wound platinum foil around the strand of the thermocouple.

  Next, although an embodiment is shown and explained in detail about the present invention, the present invention is limited to these descriptions and is not interpreted. As long as the effect of the present invention is exhibited, the embodiment may be variously modified.

  With reference to FIG. 1, the thermocouple mounting structure according to the present embodiment will be described. 1A and 1B are schematic views showing a mounting state of a thermocouple according to the present embodiment, where FIG. 1A is a plan view and FIG. The thermocouple mounting structure 100 according to the present embodiment includes an instrument 1 formed using platinum, a platinum alloy, or oxide dispersion strengthened platinum, a reinforced platinum thermocouple 11, and a temperature measurement of the reinforced platinum thermocouple 11. The contact point 10 has an attachment portion 9 fixed to the measurement target portion of the instrument 1. Here, the reinforced platinum-based thermocouple 11 has a high temperature strength with a breaking time of 100 hours or more when a stress of 10 MPa is applied at 1100 ° C. in the atmosphere, and the strands of the reinforced platinum-based thermocouple (positive electrode 2 and negative electrode) 3) is 0.1 mm or more and 2.0 mm or less, and the temperature measuring contact 10 is diffusion-bonded. In the figure, the diffusion bonded portion is indicated by reference numeral 5.

  The instrument 1 is, for example, a glass melting line instrument, a glass melting furnace, a melting tank, a defoaming layer, a clarification tank, a stirring tank, or a connecting pipe. These instruments are formed using platinum, platinum alloys or oxide dispersion strengthened platinum. The platinum alloy is, for example, a platinum-rhodium alloy, a platinum-iridium alloy, a platinum-gold alloy, a platinum-zirconium alloy, a platinum-yttrium alloy, a platinum-samarium alloy or a platinum-calcium alloy. Oxide dispersion strengthened platinum is a material in which dispersed particles such as zirconium oxide, yttrium oxide, samarium oxide, and calcium oxide are present in a matrix of platinum or a platinum rhodium alloy.

  The reinforced platinum-based thermocouple 11 is a combination of a platinum-rhodium alloy wire with a positive electrode and a pure platinum wire with a negative electrode, or a platinum-rhodium alloy wire having a composition different from that of a positive electrode with a platinum-rhodium alloy wire and a negative electrode with a positive electrode. There is a combination of lines. For example, the composition of (positive electrode, negative electrode) is (PtRh13%, Pt), (PtRh10%, Pt), (PtRh30%, PtRh6%), (PtRh40%, PtRh20%). The reinforced platinum-based thermocouple 11 is based on the above composition, and an additive component for improving the strength is added. Specifically, either one or both of the positive electrode 2 and the negative electrode 3 of the reinforced platinum-based thermocouple 11 contain a metal element or a gas element, or contain an oxide, nitride, carbide or boride. To do. Examples of the metal element contained in the platinum of the strengthened platinum present in the strand are rhodium, iridium, gold, zirconium, yttrium, samarium, and calcium. Examples of the gas element contained in the platinum of the reinforced platinum present in the strand include nitrogen, oxygen, and carbon. In addition, oxides contained in platinum of reinforced platinum present in the strands are zirconium oxide, yttrium oxide, samarium oxide, calcium oxide, and the like, and exist as dispersed particles. And since the intensity | strength of the strands (each strand of the positive electrode 2 and the negative electrode 3) has improved with these additional components, it can be used by a thin wire diameter. The wire diameter of the element wire is 0.1 mm or more and 2.0 mm or less, preferably 0.3 mm or more and 1.0 mm or less. In the present embodiment, the reinforced platinum-based thermocouple 11 refers to a thermocouple having a high temperature strength with a breaking time of 100 hours or more when the strength of the strand is applied with a stress of 10 MPa at 1100 ° C. in the atmosphere.

  The temperature measuring contact 10 is diffusion bonded. In diffusion bonding, the parts to be bonded are pressed against each other, preferably mechanically caulked, and then at a temperature lower than the melting point of the wire, in the case of a platinum-based thermocouple, a temperature of 1000 to 1700 ° C., preferably 1200 to Heating is performed at a temperature of 1500 ° C., and heat diffusion is caused between the abutting surfaces without melting the strands and thermocompression bonding is performed. Since the joining portion has not undergone the melting step, the dispersibility of the additive component for improving the strength does not collapse. Therefore, strength deterioration is prevented. The temperature measuring contact 10 is not limited to the form formed at the most distal portion of the thermocouple 11, but includes a form formed at a position before the tip. In FIG. 1, the region enclosed as the temperature measuring contact 10 indicates that this entire portion becomes the temperature measuring contact. When the positive electrode wire and the negative electrode wire are bonded, the bonded portion becomes a temperature measuring contact. However, in the embodiment shown in FIG. 1, the positive electrode strand and the negative electrode strand are not directly joined, and the chip 4 is interposed. Therefore, the region including the positive electrode wire, the negative electrode wire, and the chip between them is a temperature measuring contact.

  In this embodiment, it is not limited to the form where only the temperature measuring contact 10 is diffusion bonded. For example, there is a form in which the entire attachment portion 9 including the temperature measuring contact 10 or a part thereof is heated in a pressurized state, thereby being diffusion-bonded at the abutting portions.

  The attachment portion 9 is a portion where the temperature measuring contact 10 of the reinforced platinum thermocouple 11 is fixed to the measurement target portion of the instrument 1. The position at which the attachment portion 9 is provided is preferably the bottom wall of the instrument and the lower part of the side wall. Since the object to be melted is in contact with the wall in these places, the temperature of the object to be melted can be accurately measured.

  Next, the form in which the attachment portion 9 includes the chip 4 will be described.

  The chip 4 is made of a platinum-based material, and is preferably made of, for example, platinum, a platinum alloy, or oxide dispersion strengthened platinum. The composition of the platinum alloy or oxide dispersion strengthened platinum is the same as the composition exemplified in the instrument 1. More preferably, the tip 4 has the same composition as the instrument 1.

  It is preferable that the chip | tip 4 has a small piece shape which covers the temperature measuring contact 10 in the measurement object site | part of the instrument 1. FIG. For example, a configuration in which the temperature measuring contact 10 is disposed on the surface of the instrument 1 and the chip is a small piece covering the tip (not shown) is exemplified.

  As shown in FIG. 1B, in this embodiment, the chip 4 has facing surfaces 4a and 4b, and the facing surfaces 4a and 4b sandwich the temperature measuring contact 10 of the reinforced platinum-based thermocouple 11, More preferably, 4 is fixed to the instrument 1. When the chip 4 sandwiches the temperature measuring contact 10 of the thermocouple, the reinforced platinum thermocouple 11 is mechanically and firmly attached to the chip 4. Further, since the opposite surface 4c of the facing surface 4b can be a flat surface, the entire area of the opposite surface 4c of the facing surface 4b can contact the instrument 1. As a result, the reinforced platinum-based thermocouple 11 is attached to the instrument 1 more firmly.

  First, the shape of the chip 4 before caulking will be described with reference to FIG. FIG. 2 is a schematic view showing an example of a chip, where (a) is a front view, (b) is a right side view, and (c) is a rear view. The chip 4 has two through holes 12 and further has slits 13 so as to pass through the two through holes 12. The chip 4 has a slit shape, and the facing surfaces 4a and 4b are preferably inner surfaces of the slit. Since the wall having the facing surface 4a and the wall having the facing surface 4b are integrated via the side wall on one end side of the slit, it is easy to sandwich the thermocouple element (positive electrode 2, negative electrode 3) into the chip 4. become. Further, the faces 4a and 4b facing each other by the integration are not separated. The interval between the slits 13 is preferably smaller than the inner diameter of the through hole 12. The inner diameter of the through hole 12 needs to be larger than the diameter of the strand. The interval between the slits 13 is preferably smaller than the diameter of the strand of the thermocouple. Since the chip 4 has such a shape, the thermocouple can be passed through the through-hole, and contact between the positive electrode and the negative electrode is prevented, and the chip and the strand can be formed without increasing the caulking force. The contact area with can be increased. In addition, by providing the slits 13, it is easy to caulk because deformation deformation can be made in the direction in which the space between the slits 13 is closed when caulking.

  A method and a fixing state of fixing the thermocouple to the chip 4 shown in FIG. 2 will be described. One end of the through hole 12 is passed through the tip of the thermocouple positive electrode, and the other end of the through hole 12 is passed through the negative electrode of the thermocouple. For example, the strand is passed through the through hole 12 from the back surface of the slit 13. The tip of the strand may or may not protrude from the front through-hole 12. After passing the strand of the thermocouple through the through-hole 12 and crushing so that the plane and the bottom surface of the chip 4 approach each other, the interval between the slits 13 is reduced, and the strand is fixed to the chip 4. At this time, as shown in FIG. 1B, the inner wall of the through hole 12 and the strand of the positive electrode 2 are in contact, the inner wall of the through hole 12 and the strand of the negative electrode 3 are in contact, and the slit 13 The inner surfaces are in contact with each other. The contacted portion becomes a diffusion bonding portion indicated by reference numeral 5 in FIG. In FIG. 1B, the inner surfaces of the slits 13 are thermocompression-bonded, and the thermocompression-bonded portion is indicated by reference numeral 13 (5). Moreover, in this form, the positive electrode 2 and the negative electrode 3 do not contact each other. The temperature measuring contact 10 has a configuration in which the chip 4 is electrically interposed between the positive electrode 2 and the negative electrode 3.

  Next, an attachment state when using another type of chip 4 will be described. FIGS. 3A and 3B are schematic views showing a mounting state of a thermocouple according to another embodiment, wherein FIG. 3A is a plan view, FIG. 3B is a BB cross section, and FIG. 3C is a CC cross section. The chip 4 shown in FIG. 3 is provided with only a slit without providing a through hole. As shown in FIG. 3C, one end of the slit is connected. Since no through hole is provided, the area of contact between the inner surface of the slit and the strand of the thermocouple is small as compared with the embodiment of FIG. However, as the caulking force is increased, the slit is deformed more and the contact area can be increased.

  In addition to the U-shaped cross section shown in FIG. 2 or 4, the slit has a V-shaped cross section and a U-shaped cross section.

  FIG. 3 shows a form in which the axial direction of the strands of the thermocouple is arranged so as to face the normal direction of the wall connecting the slits, but the axial direction of the strands faces the surface direction of the wall connecting the slits. That is, it is good also as a form which pinches | interposes a slit from the side surface of a strand.

  4A and 4B are schematic views showing an example of a BB cross section, where FIG. 4A is an example in which a positive electrode and a negative electrode of a thermocouple are diffusion bonded, and FIG. 4B is a diffusion bond of a positive electrode of a thermocouple to a chip. (C) The positive electrode of the thermocouple is diffusion bonded to the chip, the negative electrode is diffusion bonded to the chip, and the positive electrode and negative electrode Are examples in which no diffusion bonding is performed. In the form shown in FIG. 4C, the positive electrode and the negative electrode are not diffusion bonded as in the form shown in FIG. The temperature measuring contact 10 has a configuration in which the chip 4 is electrically interposed between the positive electrode 2 and the negative electrode 3. In the form shown in FIG. 4A, the temperature measuring contact 10 has a form in which the positive electrode 2 and the negative electrode 3 are directly joined. In the form shown in FIG. 4B, the temperature measuring contact 10 has a form in which the positive electrode 2 and the negative electrode 3 are directly joined to each other, and the chip 4 is electrically interposed between the positive electrode 2 and the negative electrode 3. Have. In the form shown in FIG. 4C, the chip 4 is electrically interposed between the positive electrode 2 and the negative electrode 3.

  In FIG. 1, after diffusion bonding, the faces 4 a and 4 b facing each other are in contact with each other except for a portion in contact with the positive electrode 2 and the negative electrode 3 of the reinforced platinum-based thermocouple 11. FIG. 4 shows a form in which the facing surfaces 4a and 4b partially contact each other after diffusion bonding. The present embodiment includes a form in which the facing surfaces 4a and 4b are not in contact with each other after diffusion bonding. For example, in the form shown in FIG. 3 and FIG. 4, as the caulking becomes stronger, the faces 4a and 4b are not in contact with each other, then the faces 4a and 4b are partially in contact with each other, All the surfaces 4a, 4b facing each other are in contact with each other except for a portion in contact with the thermocouple, and the thermocouple is more firmly fixed.

  Next, diffusion bonding will be described. The configuration shown in FIGS. 1 and 2 is as follows. That is, as shown in FIG. 1B, the temperature measuring contact 10 is formed by diffusion bonding the positive electrode 2 of the reinforced platinum thermocouple 11 with the chip 4, diffusion bonding the negative electrode 3 with the chip 4, and positive electrode 2. And the negative electrode 3 are not diffusion bonded. A location where the positive electrode 2 and the negative electrode 3 are in contact with the chip 4 is a location 5 where diffusion bonding is performed. Moreover, since the strands of the positive electrode 2 and the negative electrode 3 are not in contact, they are not diffusion bonded. Thus, the temperature measuring contact 10 does not necessarily have a configuration in which the positive electrode 2 and the negative electrode 3 are diffusion-bonded, and even if the positive electrode 2 and the negative electrode 3 are not in contact with each other, the temperature measuring contact 10 can be connected via the chip 4. Can be formed.

  The configuration shown in FIGS. 3 and 4 is as follows. First, as shown in FIG. 4A, the temperature measuring contact 10 takes a form in which the positive electrode 2 and the negative electrode 3 of the reinforced platinum thermocouple 11 are diffusion-bonded. A portion where the strands of the positive electrode 2 and the negative electrode 3 are in contact with each other is a portion 5 where diffusion bonding is performed. Secondly, as shown in FIG. 4B, the temperature measuring contact 10 is formed by diffusion bonding the positive electrode 2 of the reinforced platinum-based thermocouple 11 with the chip 4, the diffusion electrode 3 with the chip 4, and the positive electrode. 2 and the negative electrode 3 are diffusion bonded. In addition to the location 5 where the strands of the positive electrode 2 and the negative electrode 3 are in contact with each other as a diffusion bonding, the location where the positive electrode 2 and the negative electrode 3 are in contact with the chip 4 is the location 5 where the diffusion bonding is performed. Third, as shown in FIG. 4C, the temperature measuring contact 10 is formed by diffusion bonding the positive electrode 2 of the reinforced platinum-based thermocouple 11 with the chip 4, diffusion bonding the negative electrode 3 with the chip 4, and positive electrode 2 and the negative electrode 3 are not diffusion bonded. This form is similar to FIG. 1B, and the temperature measuring contact 10 can form a contact via the chip 4 even if the positive electrode 2 and the negative electrode 3 are not in contact. In FIG.4 (c), the area | region enclosed as the temperature measuring contact 10 has shown that this whole part becomes a temperature measuring contact. In FIG. 4C, a region including the positive electrode wire, the negative electrode wire, and the chip therebetween is a temperature measuring contact.

  In any of these forms, the temperature measuring contact 10 is fixed to the instrument 1 while being covered with the chip 4. Here, the chip 4 is preferably diffusion bonded to the instrument 1. Even between the tip 4 and the instrument 1, the strength of the joined portion is not deteriorated. In addition, it is possible to join the chip to the instrument at the same time as the work of diffusion bonding the temperature measuring contact.

  Next, with reference to FIG. 5, the form using foil is demonstrated. FIG. 5 is a schematic view showing another example of the AA cross section, in which a platinum foil is sandwiched between the chip and the instrument. In the present embodiment, a platinum foil 6 having a thickness of 0.01 mm or more and 0.5 mm or less is sandwiched between the instrument 1 and the chip 4, and the abutting surfaces are diffusion bonded. preferable. Here, the surfaces that contact each other are the contact surface between the instrument 1 and the platinum foil 6 and the contact surface between the platinum foil 6 and the chip 4. Even if there is a gap between these surfaces, the gap can be filled with the platinum foil 6, so that the bonding strength can be increased. The thickness of the platinum foil 6 is more preferably 0.05 mm or greater and 0.1 mm or less. The composition of the platinum foil 6 is preferably pure platinum.

  Next, with reference to FIG. 6, the form using a board is demonstrated. FIG. 6 is a schematic view showing another example of the AA cross section, in which a plate made of a platinum-based material is sandwiched between a chip and an instrument. In this embodiment, a plate 7 made of a platinum-based material having a thickness of 0.3 mm or more and 2.0 mm or less is sandwiched between the instrument 1 and the chip 4, and the abutting surfaces are diffusion-bonded to each other. It is preferable. Here, the surfaces that contact each other are the contact surface between the instrument 1 and the plate 7 and the contact surface between the plate 7 and the chip 4. Since the plate 7 is inserted between the instrument 1 and the chip 4, the rigidity of the base part to which the chip 4 is joined is increased, and the chip 4 is hardly peeled off. The thickness of the plate 7 is more preferably 0.3 mm or greater and 1.0 mm or less. The composition of the plate 7 is preferably pure platinum, a platinum rhodium alloy, or oxide dispersion strengthened platinum. The composition of platinum rhodium alloy and oxide dispersion strengthened platinum is the same as that of the instrument 1.

  The plate 7 is preferably diffusion bonded to the instrument 1. It does not cause strength deterioration of the joined part. Moreover, the joining operation | work to the instrument of a board is attained simultaneously with the operation | work which carries out the diffusion joining of the temperature measuring contact 10.

  Next, with reference to FIG. 7, the form using a board and foil is demonstrated. FIG. 7 is a schematic view showing another example of the AA cross section, in which a plate made of a platinum-based material is sandwiched between the chip and the instrument, and a platinum foil is sandwiched between them. In the present embodiment, platinum foils 6a and 6b having a thickness of 0.01 mm or more and 0.5 mm or less are provided between the chip 4 and the plate 7, or between the instrument 1 and the plate 7, or both. It is preferable that the surfaces sandwiched and in contact with each other are diffusion bonded. Here, the abutting surfaces are the abutting surface between the instrument 1 and the platinum foil 6a, the abutting surface between the platinum foil 6a and the plate 7, the abutting surface between the plate 7 and the platinum foil 6b, and the platinum foil 6b. And a contact surface between the chip 4 and the chip 4. Since the platinum foils 6a and 6b can fill a gap between the chip 4 and the plate 7, or between the instrument 1 and the plate 7, or both, the bonding strength can be increased. The thickness of the plate 7, the thicknesses of the platinum foils 6a and 6b, and the composition thereof are the same as those described with reference to FIGS.

  Next, with reference to FIG. 8, the form which wound platinum foil around the strand is demonstrated. FIG. 8 is a schematic view showing another example of the AA cross section, and is an example in which a platinum foil is wound around a strand of a thermocouple. In the present embodiment, it is preferable that at least one of the positive electrode 2 and the negative electrode 3 of the reinforced platinum thermocouple is diffusion bonded in a state of being wound around the platinum foils 8a and 8b. The composition of the platinum foils 8a and 8b is preferably pure platinum. The thickness of the platinum foils 8a and 8b is preferably 0.01 mm or more and 0.5 mm or less, and more preferably 0.05 mm or more and 0.2 mm or less. When the diameter of the strands of the positive electrode 2 and the negative electrode 3 of the thermocouple is smaller than the inner diameter of the through-hole, the gap around the strands can be filled with the platinum foil 8, so that the adhesion is increased and the bonding strength is increased. Can do. Here, the positive electrode 2 and the wound platinum foil 8a are diffusion-bonded. The negative electrode 3 and the wound platinum foil 8b are diffusion bonded. The platinum foils 8a and 8b are not diffusion bonded to each other, the platinum foil 8a and the chip 4 are diffusion bonded, and the platinum foil 8b and the chip 4 are diffusion bonded. The platinum foil is preferably wound once on the strand. Since platinum foil is easily deformed, gaps are filled when it is caulked, adhesion is enhanced, and diffusion bonding is easily promoted. This effect can be sufficiently obtained with a single roll.

  In the form shown in FIG. 4, a platinum foil may be wound around the wire. In this case, there is a form in which the platinum foils 8a and 8b are diffusion bonded. Further, there is a form in which the platinum foils 8a and 8b are diffusion bonded, the platinum foil 8a and the chip 4 are diffusion bonded, and the platinum foil 8b and the chip 4 are diffusion bonded. Furthermore, the platinum foils 8a and 8b are not diffusion-bonded to each other, the platinum foil 8a and the chip 4 are diffusion-bonded, and the platinum foil 8b and the chip 4 are diffusion-bonded. In any form, a temperature measuring contact is formed.

  Next, a method for mounting the thermocouple in the thermocouple mounting structure according to the present embodiment will be described. In all the forms shown in FIG. 1 to FIG. 8, first, a portion that becomes the temperature measuring contact 10 is mechanically joined. Specifically, by sandwiching with pliers or the like, the chip 4, the positive electrode 2, the negative electrode 3, and the like are deformed, and accordingly, the contact area with each other increases. Next, in a state where the portion to be the temperature measuring contact 10 is pressurized, it is heated to a temperature of 1000 ° C. or more and thermally diffused to perform diffusion bonding. Heating methods include heating with a burner, induction heating, and energization heating. The heating temperature is preferably 1200 ° C to 1500 ° C. Although temperature measurement may be difficult depending on the heating method, there is no particular limitation as long as it is a temperature at which diffusion bonding occurs without melting. Specifically, the upper limit is the temperature at which the chip 4, the positive electrode 2, the negative electrode 3, if necessary, the platinum foil 6, the platinum foil 8, the plate 7 made of a platinum material does not melt, and the temperature at which thermal diffusion starts to occur, It is preferable to proceed with the work.

  The operation of performing the diffusion bonding is preferably a mode in which the operation of bonding the chip to the instrument is performed simultaneously with the operation of diffusion bonding the temperature measuring contact. High work efficiency. Further, a mode in which the work of diffusion bonding the temperature measuring contact using the chip and the thermocouple is performed first, and then the work of bonding the chip to the instrument may be employed. Although the work efficiency is inferior, this joining work may be better depending on the shape of the instrument.

DESCRIPTION OF SYMBOLS 100 Thermocouple mounting structure 1 Instrument 2 Positive electrode 3 Negative electrode 4 Chips 4a and 4b Opposing surfaces 5 Diffusion-bonded portions 6, 6a and 6b Platinum foil 7 Plates 8, 8a and 8b made of a platinum-based material Platinum foil 9 Mounting portion 10 Temperature measuring contact 11 Reinforced platinum thermocouple 12 Through hole 13 Slit

Claims (13)

A fixture formed using platinum, a platinum alloy or oxide dispersion strengthened platinum, a reinforced platinum thermocouple, and a mounting portion in which a temperature measuring contact of the reinforced platinum thermocouple is fixed to a measurement target portion of the fixture. And a thermocouple mounting structure comprising:
The reinforced platinum-based thermocouple has a high temperature strength with a breaking time of 100 hours or more when a stress of 10 MPa is applied at 1100 ° C. in the atmosphere,
The thermocouple mounting structure, wherein a wire diameter of the reinforced platinum thermocouple is 0.1 mm or more and 2.0 mm or less, and the temperature measuring contact is diffusion-bonded. The mounting portion has a chip made of a platinum-based material,
The temperature measuring contact is
(1) Whether the positive electrode of the reinforced platinum-based thermocouple is diffusion bonded to the chip, the negative electrode is diffusion bonded to the chip, and the positive electrode and the negative electrode are not diffusion bonded.
(2) The positive electrode and the negative electrode of the reinforced platinum thermocouple are diffusion bonded, or
(3) The positive electrode of the reinforced platinum thermocouple is diffusion bonded to the chip, the negative electrode is diffusion bonded to the chip, and the positive electrode and the negative electrode are diffusion bonded. The thermocouple mounting structure according to claim 1, wherein the thermocouple mounting structure is fixed to the instrument while being covered with the chip. The tip has opposing faces;
The thermocouple mounting structure according to claim 2, wherein the facing surfaces sandwich a temperature measuring contact of the reinforced platinum-based thermocouple, and the tip is fixed to the instrument. The tip has a slit shape;
The thermocouple mounting structure according to claim 3, wherein the facing surface is an inner surface of the slit.   The thermocouple mounting structure according to claim 2, wherein the chip is diffusion-bonded to the instrument.   3. A platinum foil having a thickness of 0.01 mm or more and 0.5 mm or less is sandwiched between the device and the chip, and the abutting surfaces are diffusion-bonded to each other. The thermocouple mounting structure according to any one of -4.   A plate made of a platinum-based material having a thickness of 0.3 mm or more and 2.0 mm or less is sandwiched between the device and the chip, and the surfaces that come into contact with each other are diffusion bonded. The thermocouple mounting structure according to any one of claims 2 to 4.   The thermocouple mounting structure according to claim 7, wherein the plate is diffusion-bonded to the instrument. A platinum foil having a thickness of 0.01 mm or more and 0.5 mm or less is sandwiched between the chip and the plate, or between the instrument and the plate, or both. 8. The thermocouple mounting structure according to claim 7, wherein the contacting surfaces are diffusion-bonded to each other.   The thermocouple according to any one of claims 1 to 9, wherein at least one of the positive electrode and the negative electrode of the reinforced platinum-based thermocouple is diffusion bonded in a state of being wound around a platinum foil. Mounting structure.   At least one of the positive electrode and the negative electrode of the reinforced platinum-based thermocouple contains a metal element or a gas element, or contains at least one of oxide, nitride, carbide, or boride. The thermocouple mounting structure according to any one of claims 1 to 10, wherein the thermocouple mounting structure is any one of the above.   The thermoelectric device according to any one of claims 1 to 11, wherein the instrument is an instrument for a glass melting line, a glass melting furnace, a melting tank, a defoaming layer, a clarification tank, a stirring tank, or a connecting pipe. Pair mounting structure. A method for attaching the thermocouple in the thermocouple attachment structure according to any one of claims 1 to 12,
Mounting a thermocouple characterized by having a step of mechanically bonding the portion to be the temperature measuring contact, heating the portion to a temperature of 1000 ° C. or higher and thermally diffusing the portion while pressurizing the portion. Method.

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