JP6885587B2 - Fluorescent fiber optic thermometer - Google Patents

Description

The present invention relates to a fluorescent optical fiber thermometer, and more particularly to a fluorescent optical fiber thermometer that improves repeatability.

As a fluorescent optical fiber thermometer, one in which a phosphor and the tip of an optical fiber tube are covered with a metal cap has been proposed (see, for example, Patent Document 1). This fluorescent optical fiber thermometer has a metal cap that facilitates heat transfer to the phosphor to improve the response speed.

Japanese Unexamined Patent Publication No. 11-31576

By the way, in the above-mentioned fluorescent fiber thermometer, when the metal cap is pressed against the object to be detected, the measurement accuracy is lowered if the metal cap and the object to be detected are in a one-sided contact state. Therefore, if the above-mentioned fluorescent optical fiber thermometer is mechanically incorporated into a device that presses the object to be detected by using an actuator or the like, there is a possibility that a one-sided contact state and a non-one-sided state may be repeated. That is, there is a problem that the repeatability is lowered because the contact area between the cap and the object to be detected changes significantly every time the measurement is performed.

The present invention has been made in view of the above, and an object of the present invention is to provide a fluorescent optical fiber thermometer capable of improving repeatability.

The fluorescent optical fiber thermometer of the present invention that solves the above problems is a fluorescent optical fiber thermometer having a phosphor at the tip of the optical fiber tube, in which the tip of the optical fiber tube and the phosphor are bottomed tubular. It is covered with a tilting cylinder, and the tip of the tilting cylinder is covered with a bottomed tubular contact cylinder. The contact cylinder is made of a metal material having a thermal conductivity of 100 W / mk or more and is the same. The outer bottom is configured to be pressed against the object to be detected, and the inner bottom has a recess that deepens toward the tip side in the center, and the tilting tube is made of a metal material having a thermal conductivity of 100 W / mk or more. , its outsole has a bulge increases toward the leading end side, in a state in which the contact cylinder is pressed to the detected body, bulging of the tilting cylinder is slidably fitted in the recess of the contact cylinder Mari, When the optical fiber tube and the tilting cylinder are tiltably connected to the contact cylinder and the bulge fits into the recess, an intermediate member is provided between the recess and the bulge, and the intermediate member is said to be the intermediate member. It is characterized by having a hardness higher than that of the dent and the bulge.

According to the present invention, when the contact cylinder covering the phosphor and the tilting cylinder are pressed against the object to be detected, the bulge of the tilting cylinder fits into the recess of the contact cylinder and slides to form a tiltable joint. By functioning, it is possible to avoid one-sided contact between the outer bottom of the contact cylinder and the object to be detected. This is advantageous for keeping the contact area between the outer bottom of the contact cylinder and the object to be detected constant when pressed against the object to be detected, and the repeatability can be improved.

It is a vertical cross-sectional view which illustrates the 1st Embodiment of the fluorescent optical fiber thermometer of this invention, and shows the state which separated the contact cylinder from the detected body. The state in which the contact cylinder of the fluorescent optical fiber thermometer of FIG. 1 is pressed against the object to be detected is shown. The state in which the optical fiber tube and the tilting cylinder of the fluorescent optical fiber thermometer of FIG. 1 are tilted with respect to the contact cylinder is shown. It is a perspective view which illustrates the process of assembling the fluorescent optical fiber thermometer of FIG. It is a relational figure which illustrates the relationship between the temperature and an error in the fluorescent optical fiber thermometer of FIG. It is a vertical cross-sectional view which illustrates the 2nd Embodiment of the fluorescent optical fiber thermometer of this invention, and shows the state which separated the contact cylinder from the detected body. The state in which the contact cylinder of the fluorescent optical fiber thermometer of FIG. 6 is pressed against the object to be detected is shown. It is a vertical cross-sectional view which illustrates the calibrator which calibrates the fluorescent optical fiber thermometer of this invention.

Hereinafter, embodiments of the fluorescent optical fiber thermometer of the present invention will be described with reference to the drawings. In the present specification, the tip indicates the end on the side to be detected at the lower end in the drawing, and the end means the end on the opposite side to the object to be detected at the upper end in the drawing.

As illustrated in FIGS. 1 to 4, the fluorescent optical fiber thermometer 10 of the first embodiment has a phosphor 12 at the tip of the optical fiber tube 11. In the fluorescent optical fiber thermometer 10, the excitation light projected from a light source (not shown) is received by the phosphor 12 via the optical fiber tube 11, and the fluorescence generated from the phosphor 12 that receives the excitation light is received. The temperature of the object to be detected 13 is measured based on the time when the brightness of the object 13 decays.

In the fluorescent optical fiber thermometer 10, the tip of the optical fiber tube 11 and the phosphor 12 are covered with the tubular body 14, and the portion other than the tip of the optical fiber tube 11 is covered with the covering material 15.

The optical fiber tube 11 is made of transparent quartz, glass, or plastic, and is composed of a wire formed by arranging a clad having a refractive index lower than that of the core on the outer periphery of the core in the center. The excitation light and fluorescence incident on the optical fiber tube 11 propagate through the core by repeating total reflection and refraction by the cladding.

The phosphor 12 heats a mixture of fluorescent powders such as magnesium-based fluorescent materials, yttrium aluminum garnet-based fluorescent materials, and cesium-based fluorescent materials and inorganic adhesives containing ceramic powders such as ceramic adhesives. Formed by curing. The ceramic adhesive is mainly composed of a ceramic powder of any or a combination of alumina, silica, and zirconia and a curing liquid such as an inorganic polymer, and is in the form of a colored paste having a viscosity of 40 Pas or more at a standard temperature. It is a high-viscosity adhesive. The ceramic adhesive may be a material other than the above as long as it is an inorganic adhesive containing ceramic powder and a curing liquid as main components. Further, it may be other than the one-component heat-curing type, and the ceramic powder and the curing liquid may be mixed separately.

The tubular body 14 has a bottomed tubular shape whose tip is closed by the bottom 16 and whose end is open, and is made of a transparent material such as glass or a thermosetting resin.

The covering material 15 is made of a ceramic tube. The ceramic tube is a tube obtained by sintering ceramic and has both ends open. In addition to this, as the covering material 15, a tube made of aromatic polyetherketone or stainless steel can be exemplified. By covering the outer surface of the optical fiber tube 11 with the coating material 15 in this way, it is advantageous to improve the durability.

The optical fiber tube 11, the phosphor 12, and the tubular body 14 are integrated by fixing the optical fiber tube 11 to the vicinity of the end of the tubular body 14 and the phosphor 12 to the bottom 16 of the tubular body 14, respectively.

Specifically, a mixture of a fluorescent powder and a ceramic adhesive is filled in the bottom 16 of the cylinder 14. Next, the mixture is heat-cured at a temperature of 70 ° C. or higher and 200 ° C. or lower to form a fluorescent substance 12 and the fluorescent substance 12 is fixed to the bottom 16. Next, the tip of the optical fiber tube 11 is inserted into the tubular body 14 and comes into contact with the phosphor 12.

As illustrated in FIGS. 1 to 4, in the fluorescent optical fiber thermometer 10, the tip of the optical fiber tube 11 and the phosphor 12 are covered with a bottomed tubular tilting cylinder 30, and the tilting cylinder 30 The tip is covered with a bottomed tubular contact cylinder 20. That is, in the fluorescent optical fiber thermometer 10, the cylinder body 14 is covered with two bottomed tubular members, a tilting cylinder 30 and a contact cylinder 20.

The contact cylinder 20 and the tilting cylinder 30 are made of aluminum. The contact cylinder 20 and the tilt cylinder 30 may be made of a metal material having a thermal conductivity of 100 W / mk or more. Examples of such a metal material include, for example, an aluminum alloy in addition to aluminum. Further, the contact cylinder 20 and the tilt cylinder 30 may be made of different metal materials.

The contact cylinder 20 is composed of two members, a contact head 21 and a lid portion 22, and has an outer bottom 23 facing the tip side that can be pressed against the detected body 13 and an inner bottom facing the end side. It has a recess 25 in the center of 24. The tilting cylinder 30 is composed of a tilting head 31 and a cylinder portion 32, has a bulge 35 in the center of an outer bottom 33 facing the tip side, and has a phosphor 12 on an inner bottom 34 facing the end side. The bottom 16 of the covering cylinder 14 is arranged.

The contact cylinder 20 and the tilting cylinder 30 are connected by arranging the tilting head 31 of the tilting cylinder 30 inside the contact head 21 of the contact cylinder 20 and then fitting the lid portion 22 into the contact head 21. It is configured to be possible.

The contact head 21 is a bottomed tubular member whose tip is closed by the bottom and whose end is open, and has an outer bottom 23 and an inner bottom 24. The lid portion 22 is an annular member and has an engaged portion 26 and a tilt stop portion 27.

The outer bottom 23 is configured to be in surface contact with the body to be detected 13, and its shape is formed in a circular shape. The shape of the outer bottom 23 may be formed into a rectangle or a polygon. The area S1 of the outer bottom 23 is set to a value of 7 times or more and 15 times or less the cross-sectional area S2 of the optical fiber tube 11.

The inner bottom 24 is raised toward the end side of the contact head 21 with respect to the outer bottom 23. The inner bottom 24 has a recess 25 in the central portion that becomes deeper toward the tip end side. The recess 25 is a substantially hemispherical recess, and the shape thereof is formed so as to be spherically contactable with the bulge 35 of the tilting cylinder 30 described later. Specifically, the shape of the recess 25 is a concave spherical shape that is recessed from the end side to the tip side, and the diameter of the spherical surface is substantially the same as the diameter of the spherical surface of the bulge 35.

The engaged portion 26 is formed by projecting the lower end of the lid portion 22 radially inward from the inner cylinder surface of the contact cylinder 20 so as to narrow the opening at the end of the contact head 21. The engaged portion 26 is a portion that can be engaged with the engaging portion 36 of the tilting cylinder 30 described later, and may be composed of a plurality of protrusions protruding inward in the radial direction from the inner cylinder surface near the end. Good.

The tilt stop portion 27 is formed by projecting the upper end of the lid portion 22 radially inward from the inner peripheral edge so as to narrow the opening at the end of the lid portion 22. The tilt stop portion 27 is a portion that comes into contact with the tilted stop portion 37 of the tilt cylinder 30 when the optical fiber tube 11 and the tilt cylinder 30 are tilted. It may be composed of protrusions.

The tilting cylinder 30 is formed so that the tilting head 31 projects radially outward from the cylinder portion 32 so as to exhibit a mushroom shape in which an umbrella is arranged on the tip side, the tip is closed by the bottom, and the end is opened. It is a bottomed tubular member. The tilting head 31 has an outer bottom 33 facing the tip side and an inner bottom 34 facing the end side, and also has an engaging portion 36. The cylinder portion 32 has a tilted stop portion 37 formed on the outer cylinder surface.

The outer bottom 33 has a bulge 35 that becomes higher toward the tip end side. The bulge 35 is a substantially hemispherical convex portion, and the shape thereof is formed so as to be spherically contactable with the recess 25 of the contact cylinder 20 described above. Specifically, the shape of the bulge 35 is a convex spherical shape that bulges from the end side to the tip side, and the diameter in the sphere is substantially the same as the diameter in the sphere of the dent 25.

The inner bottom 34 is arranged inside the bulge 35. The inner bottom 34 is in contact with the bottom 16 of the tubular body 14, and the bottom 16 of the tubular body 14 is interposed between the inner bottom 34 and the phosphor 12. By arranging the inner bottom 34 inside the bulge 35, when the contact cylinder 20 is pressed against the object to be detected 13, the phosphor 12 is located inside the dent 25 with the bulge 35 fitted in the dent 25. It will be. The inner bottom 34 may be fixed to the bottom 16 of the tubular body 14 with an adhesive.

The engaging portion 36 is formed by projecting the upper end of the tilting head 31 radially outward from the outer peripheral edge of the tilting head 31. The engaging portion 36 is arranged to face the engaged portion 26 between the inner bottom 24 of the contact cylinder 20 and the engaged portion 26 when the lid portion 22 is fitted to the end of the contact head 21. ing.

The end of the cylinder portion 32 is arranged above the lid portion 22 of the contact cylinder 20. The tubular portion 32 has a tilted stop portion 37 formed on the outer cylinder surface, and the length from the tip to the end of the tilted stop portion 37 is longer than the length from the tip to the end of the tilt stop portion 27.

Further, the fluorescent optical fiber thermometer 10 includes an intermediate member 40 interposed between the recess 25 and the bulge 35 when the bulge 35 of the tilting cylinder 30 fits into the recess 25 of the contact cylinder 20, and the contact cylinder. The outer surface of 20 is covered with the outer member 41.

The intermediate member 40 is configured to include a member having a hardness higher than that of the recess 25 and the bulge 35 in a high temperature environment of 150 ° C. or higher. The intermediate member 40 is interposed between the recess 25 and the bulge 35 so that the recess 25 and the bulge 35 do not come into direct contact with each other in a high temperature environment due to the member having a high hardness.

Specifically, the intermediate member 40 of this embodiment is a thin film containing a sintered body such as ceramic, which has a higher hardness than aluminum in a high temperature environment, and covers the entire area of the recess 25 of the contact cylinder 20. The intermediate member 40 is formed by applying a ceramic-based paint to the spherical surface of the recess 25 and then drying it. The intermediate member 40 may cover the bulge 35 of the tilting cylinder 30, or may cover the dent 25 and the bulge 35.

The outer member 41 has a hardness higher than that of the outer surface of the contact cylinder 20 in a high temperature environment of 150 degrees or higher. The outer surface of the outer member 41 is the object to be detected 1 in a high temperature environment.
The entire outer surface is covered so as not to come into direct contact with 3.

Specifically, the outer member 41 of this embodiment is a film (anodized) made of aluminum oxide having a hardness higher than that of aluminum in a high temperature environment, and covers the entire outer surface of the contact head 21 of the contact cylinder 20. That is, it covers the outer bottom 23 of the contact head 21 and the outer cylinder surface. The outer member 41 is formed by oxidizing the aluminum on the outer surface of the contact head 21 by an anodic oxidation treatment.

Next, the operation of the fluorescent optical fiber thermometer 10 will be described with reference to FIGS. 1 to 3. FIG. 1 illustrates a state in which the contact cylinder 20 is separated from the detected body 13, FIG. 2 illustrates a state in which the contact cylinder 20 is pressed against the detected body 13 to measure the temperature, and FIG. 3 shows an optical fiber tube. The state in which the eleven and the tilting cylinder 30 are tilted with respect to the contact cylinder 20 is illustrated.

As illustrated in FIG. 1, in the fluorescent optical fiber thermometer 10, when the contact cylinder 20 is separated from the object to be detected 13, the engaging portion 36 engages with the engaged portion 26, whereby the contact cylinder 20 And the tilting cylinder 30 are configured to be connected. On the other hand, in the fluorescent optical fiber thermometer 10, as illustrated in FIGS. 2 and 3, when the contact cylinder 20 is pressed against the object to be detected 13, the engaging portion 36 is separated from the engaged portion 26 and is separated from the engaged portion 26. The bulge 35 of the tilting cylinder 30 is slidably fitted in the recess 25 of the contact cylinder 20, and the optical fiber tube 11 and the tilting cylinder 30 are tiltably connected to the contact cylinder 20.

More specifically, as shown in FIG. 1, when the contact cylinder 20 is separated from the detected body 13, the contact cylinder 20 tends to move toward the detected body 13 due to its own weight. At this time, the engaging portion 36 abuts and engages with the engaged portion 26. As a result, the movement of the contact cylinder 20 toward the detected body 13 is restricted.

As described above, the engaging portion 36 and the engaged portion 26 may be configured such that the contact cylinder 20 does not separate from the tilting cylinder 30 when the contact cylinder 20 is not pressed by the detected body 13. For example, instead of the engaging portion 36 and the engaged portion 26, a plurality of strings for joining the contact cylinder 20 and the tilting cylinder 30 may be used.

As shown in FIG. 2, when measuring the temperature of the detected body 13, the measurer holds a handle (not shown) on the terminal side and presses the contact cylinder 20 against the detected body 13. At this time, with the engaging portion 36 separated from the engaged portion 26, the bulge 35 loosely fits into the recess 25 and comes into spherical contact. As a result, heat is transferred from the detected body 13 to the phosphor 12 via the contact cylinder 20 and the tilting cylinder 30, so that the temperature of the detected body 13 can be measured.

Further, in a high temperature environment of 150 ° C. or higher, the intermediate members 40 interposed between the recess 25 and the bulge 35 maintain their respective surface shapes by making them non-contact, and are fixed by melting. Functions to suppress. Specifically, the intermediate member 40 is brought into a non-contact state by the sintered body contained in the paint without bringing the recess 25 and the bulge 35 into contact with each other.

Similarly, the outer member 41 covering the outer surface of the contact head 21 of the contact cylinder 20 functions to keep the outer surface of the contact head 21 non-contact to maintain the outer surface shape and suppress sticking due to melting. To do.

As shown in FIG. 3, when the posture of the measurer changes during the temperature measurement, that is, when the measurer moves the handle in a direction other than the pressing direction while pressing the contact tube 20 against the detected body 13. Alternatively, when the contact cylinder 20 is pressed against the object to be detected 13 in a one-sided contact state, the optical fiber tube 1
1 and the tilting cylinder 30 tilt with respect to the contact cylinder 20.

Specifically, the tilting cylinder 30 functions like a tiltable joint, for example, a ball joint, with the bulge 35 in spherical contact with the recess 25 as a fulcrum. As a result, the optical fiber tube 11 and the tilting cylinder 30 tilt with respect to the contact cylinder 20 with the spherical contact of the bulge 35 and the depression 25 as fulcrums. In this way, the optical fiber tube 11 and the tilting cylinder 30 are tilted with respect to the contact cylinder 20 until the tilted stop portion 37 and the tilt stop portion 27 come into contact with each other. Due to this tilting, the outer bottom 23 of the contact cylinder 20 comes into surface contact with the body to be detected 13 without hitting one side.

As described above, when the contact cylinder 20 and the tilting cylinder 30 covering the phosphor 12 are pressed against the object to be detected 13, the bulge 35 of the tilting cylinder 30 fits into the recess 25 of the contact cylinder 20, and the tiltable joint. By functioning as, it is possible to avoid one-sided contact between the outer bottom 23 of the contact cylinder 20 and the detected body 13. This is advantageous for maintaining the contact area between the outer bottom 23 of the contact cylinder 20 and the detected body 13 when pressed against the detected body 13 at all times, and the repeatability can be improved.

Even if the fluorescent optical fiber thermometer 10 is mechanically pressed against the object to be detected 13 by an actuator or the like, one-sided contact can be avoided. This is advantageous in suppressing a significant change in the contact area between the outer bottom 23 and the object to be detected 13 each time the measurement is performed, and the repeatability can be improved.

Further, since the area S1 of the outer bottom 23 is larger than the cross-sectional area S2 of the optical fiber tube 11, it is advantageous to secure the contact area, and the amount of heat transferred from the detected body 13 to the phosphor 12 is increased. Can be increased. Along with this, the response speed at the time of measurement can be improved.

In addition, each of the two bottomed tubular members covering the tubular body 14 is made of a metal material having a thermal conductivity of 100 W / mk or more, so that the heat transferred from the detected body 13 to the phosphor 12 is transferred. Since the decrease in transmission can be suppressed, it is advantageous for improving the response speed.

Further, in a state where the contact cylinder 20 is pressed by the object to be detected 13, the recess 25 and the bulge 35 come into spherical contact with each other, so that the recess 25 and the bulge 35 come into contact with each other while maintaining a slidable state. The area can be maximized. This is advantageous in suppressing a decrease in the amount of heat transferred from the contact cylinder 20 to the tilt cylinder 30.

As illustrated in FIG. 5, when the intermediate member 40 and the outer member 41 are omitted, the measurement error may become smaller when the temperature exceeds 150 degrees. This is because the dent 25 and the bulge 35 are thermally deformed in a high temperature environment of 150 ° C. or higher to increase the contact area, and the dent 25 and the bulge 35 are melted and fixed to form the contact cylinder 20 and the tilting cylinder. The factor is that the thermal conductivity of 30 is high.

On the other hand, in the fluorescent optical fiber thermometer 10 of the embodiment, the surface shapes of the recess 25 and the bulge 35 are maintained by the intermediate member 40, and the sticking due to melting is suppressed. Therefore, the estimation error in a high temperature environment exceeding the temperature Ta can be increased. This is advantageous for maintaining a linearity in the relationship between temperature and error in a high temperature environment, and by making corrections based on the linearity, the temperature can be measured with higher accuracy.

In this way, when measuring the temperature in a special environment such as a high temperature environment, if the alignment in the relationship between the temperature and the error can be maintained, the measurement accuracy can be improved even if the estimation error becomes large in the high temperature environment. Can be made smaller.

Further, since the intermediate member 40 maintains good tilting of the optical fiber tube 11 and the tilting tube 30 with respect to the contact tube 20, it is advantageous for improving the repeatability in a high temperature environment. The intermediate member 40 may be configured to include a member having a hardness higher than that of the recess 25 and the bulge 35 in a high temperature environment. For example, the intermediate member 40 may be composed of alumite like the outer member 41. Good.

Similarly, in the fluorescent optical fiber thermometer 10 of the embodiment, the outer member 41 suppresses the sticking of the outer bottom 23 of the contact cylinder 20 due to distortion or melting. As a result, the temperature can be measured with high accuracy, and it is advantageous for improving the repeatability. The outer member 41 may have a hardness higher than that of the outer surface of the contact cylinder 20 in a high temperature environment. For example, a thin film formed of a paint containing a sintered body like the intermediate member 40. It may be composed of.

As illustrated in FIGS. 6 and 7, the fluorescent optical fiber thermometer 10 of the second embodiment has a different structure of the intermediate member 40 from the first embodiment and is filled with grease 42. The intermediate member 40 of this embodiment is made of an alumite film and covers the bulge 35 of the tilting cylinder 30.

The grease 42 is composed of a fluorinated grease in which a fluorinated oil (PFAE) is uniformly diffused as a lubricating oil and a fluororesin (PTFE) is uniformly diffused as a thickener, and is filled inside the contact cylinder 20. The grease 42 plays a role of increasing the degree of adhesion between the dent 25 and the bulge 35 covered with the intermediate member 40, and improves the thermal conductivity from the dent 25 to the bulge 35.

When the bulge 35 fits into the dent 25, the grease 42 may be interposed between the dent 25 and the bulge 35 covered with the intermediate member 40, and at least the dent 25 inside the contact cylinder 20 is filled. You just have to. However, the amount of grease 42 filled is adjusted so that when the bulge 35 fits into the recess 25, it does not overflow from the inside of the contact cylinder 20 to the outside.

As described above, even if the intermediate member 40 is made of an alumite film, the surface shapes of the recess 25 and the bulge 35 can be maintained and the sticking due to melting can be suppressed in a high temperature environment.

Further, by using the grease 42, it is advantageous to improve the thermal conductivity between the contact cylinder 20 and the tilting cylinder 30 as compared with the first embodiment, and the response speed can be improved.

When the contact cylinder 20 is pressed against the object to be detected 13 arranged above from below to above, the grease 42 may flow out from the inside of the contact cylinder 20 to the outside. Therefore, the fluorescent optical fiber thermometer 10 of the second embodiment includes a sealing member 43.

The sealing member 43 is made of an elastomer and is a packing that seals between the tilted stop portion 37 and the tilt stop portion 27, which are through portions, so that the grease 42 does not leak from the inside of the contact cylinder 20. .. The seal member 43 is joined to the tip end side of the tilt stop portion 27. The seal member 43 may be joined to the tilted stop portion 37.

By joining the seal member 43 to the tip side, the amount of elastic deformation of the seal member 43 can be reduced when the optical fiber tube 11 and the tilting cylinder 30 are tilted with respect to the contact cylinder 20, so that the tilting is not hindered. Leakage of grease 42 can be prevented.

In the above-described embodiment, a mixture of a fluorescent powder and an inorganic adhesive containing a ceramic powder is heated and cured. As a result, the effect of curing the inorganic polymer by changing to a reticulated polymer with a high crosslink density and the effect of maintaining a high solid content by the heat-resistant ceramic powder and preventing volume shrinkage during curing are achieved. The fluorescent powder is cured to be integrated to form the phosphor 12, and is fixed to the inside of the tubular body 14. Therefore, after heat curing, the phosphor 12 that can withstand a high temperature of 1000 degrees can be formed due to the high heat resistance and high adhesive properties of the ceramic adhesive. Further, it is advantageous to maintain the fixed state of the phosphor 12 and the tubular body 14 without peeling due to the high adhesive strength even in a high temperature environment.

Further, by forming the tubular body 14 with a transparent material, it is advantageous to check the degree of adhesion between the optical fiber tube 11 and the phosphor 12. Further, as the diameter of the optical fiber tube 11 is 0.4 mm or more and 1.0 mm or less, the phosphor 12 becomes smaller. Therefore, it is difficult to directly fix the optical fiber tube 11 and the phosphor 12. Therefore, by fixing the phosphor 12 to the bottom of the tubular body 14 and fixing the optical fiber tube 11 near the opening of the tubular body 14, the optical fiber tube 11 and the phosphor 12 can be easily connected via the tubular body 14. Can abut. As a result, the yield rate can be improved.

Further, the optical fiber tube 11 may be formed by integrating a plurality of strands with an adhesive. When the optical fiber tube 11 is composed of a single wire, the diameter of the wire is 0.4 mm or more and 1.0 mm or less. On the other hand, when the optical fiber tube 11 is configured by integrating a plurality of strands, the value of the total area obtained by multiplying the area of the strands by the number of strands is 0.1 mm ² or more and 0.8 mm ² or less. In addition, the diameter of the wire is formed to be 0.05 mm or more and 0.2 mm or less, and the number of the wires is 5 or more and 10 or less. When the optical fiber tube 11 is composed of a plurality of wires integrated with an adhesive, the bending radius of the optical fiber tube 11 can be reduced as compared with the case where the optical fiber tube 11 is composed of a single wire, which is advantageous for handling. become.

In the above-described embodiment, by arranging the end of the cylinder portion 32 above the lid portion 22 of the contact cylinder 20, even if the optical fiber tube 11 and the tilting cylinder 30 are tilted at the maximum angle with respect to the contact cylinder 20. , It is possible to surely prevent the optical fiber tube 11 from coming into contact with the tilt stop portion 27. This is advantageous in preventing damage to the optical fiber tube 11 due to tilting.

Further, when the contact cylinder 20 is pressed against the object to be detected 13, the phosphor 12 is located inside the recess 25 with the bulge 35 fitted in the recess 25, so that the phosphor 12 is brought closer to the object 13 to be detected. be able to. This is advantageous for improving the response speed.

As illustrated in FIG. 8, the fluorescent optical fiber thermometer 10 of the above-described embodiment is calibrated using the calibrator 50. The calibrator 50 includes a Dewar bottle 51, an inner box 52, a bottom base 53, a heat equalizing block 54, a heater 55, a calibration thermometer 56, and a control device 57.

The Dewar bottle 51 is a bottle made of stainless steel and in which the space between the inner layer and the outer layer is evacuated. The inner box 52 is made of stainless steel and is formed in a bottomed tubular shape with the lower end closed. Liquid nitrogen is filled between the Dewar bottle 51 and the inner box 52 as a coolant 58.

The bottom upper table 53 is a table that lifts and supports the lower end of the heat equalizing block 54 upward, and also has a role of not directly contacting the bottom of the inner box 52 and the inner cylinder surface of the heat equalizing block 54. The heat equalizing block 54 is made of copper. The upper end of the heat equalizing block 54 is arranged near the upper ends of the Dewar bottle 51 and the inner box 52, and may be arranged above the upper ends of the Dewar bottle 51 and the inner box 52. The heat equalizing block 54 has a heater installation hole 54a and a thermometer installation hole 54b formed by cutting downward from the upper end. The upper end of the heat equalizing block 54 is a contact surface 54c that abuts the contact cylinder 20 of the fluorescent optical fiber thermometer 10.

The heater 55 is composed of an electric heater and is inserted into the heater installation hole 54a. The calibration thermometer 56 is composed of a thermocouple and is inserted into the thermometer installation hole 54b.

The control device 57 is hardware composed of a CPU that performs various information processing, an internal storage device that can read and write programs and information processing results used for performing the various information processing, and various interfaces. The control device 57 is electrically connected to the fluorescent optical fiber thermometer 20, the heater 55, and the calibration thermometer 56 via a signal line indicated by an alternate long and short dash line.

A method of calibrating the fluorescent optical fiber thermometer 10 will be described. First, the cooling liquid 58 is filled between the Dewar bottle 51 and the inner box 52 to cool the soaking block 54. Next, the temperature T1 of the soaking block 54 is acquired by the calibration thermometer 56. Next, based on the acquired temperature T1, the soaking block 54 is heated by the heater 55 to keep the temperature T1 constant.

Next, the contact cylinder 20 of the fluorescent optical fiber thermometer 10 is brought into contact with the contact surface 54c. Next, the temperature T2 is acquired by the fluorescent optical fiber thermometer 10. Next, the fluorescent optical fiber thermometer 10 is calibrated based on the difference T4 between the acquired temperature T2 and the temperature T3 calculated based on the temperature T1. The temperature T3 is a temperature preset by experiments or tests, and may be calculated using, for example, a map set based on the relationship between the outside air temperature and the temperature T1.

When the contact surface 54c is arranged toward the bottom of the Dewar bottle 51 and the inner box 52, the entire fluorescent optical fiber thermometer 10 is cooled by the influence of the coolant 58. That is, even when the contact cylinder 20 of the fluorescent optical fiber thermometer 10 is not in close contact with the contact surface 54c, or when the recess 25 of the contact cylinder 20 and the bulge 35 of the tilting cylinder 30 are not in spherical contact, the contact surface 54c A value close to the surface temperature of is measured.

In this regard, in the temperature calibrator 50, the contact surface 54c on which the contact cylinder 20 of the fluorescent optical fiber thermometer 10 is pressed is arranged near the upper ends of the Dewar bottle 51 and the inner box 52. That is, the fluorescent optical fiber thermometer 10 is calibrated with a temperature difference between the contact surface 54c and the outside air. Therefore, it is possible to discriminate between the case where the fluorescent optical fiber thermometer 10 accurately measures the surface temperature of the contact surface 54c and the case where it cannot be measured by the temperature difference. This is advantageous for correctly calibrating the fluorescent optical fiber thermometer 10, and the measurement accuracy of the fluorescent optical fiber thermometer 10 can be improved.

It should be noted that if the periphery of the portion where the contact cylinder 20 of the fluorescent optical fiber thermometer 10 comes into contact is covered with an enclosure block made of copper, more accurate calibration becomes possible.

10 Fluorescent optical fiber thermometer 11 Optical fiber tube 12 Fluorescent material 20 Contact cylinder 23 Outer bottom 24 Inner bottom 25 Depression 30 Tilt cylinder 33 Outer bottom 35 Bulge 40 Intermediate member 41 Outer member

Claims (7)

In a fluorescent optical fiber thermometer having a phosphor at the tip of an optical fiber tube,
The tip of the optical fiber tube and the phosphor are covered with a bottomed tubular tilting tube, and the tip of the tilting tube is covered with a bottomed tubular contact tube.
The contact cylinder is made of a metal material having a thermal conductivity of 100 W / mk or more, and its outer bottom is configured to be pressed against the object to be detected, and a recess deepening toward the tip side is formed in the center of the inner bottom thereof. Have and
The tilting cylinder is made of a metal material having a thermal conductivity of 100 W / mk or more, and has a bulge on its outer bottom that increases toward the tip side.
With the contact cylinder pressed against the object to be detected, the bulge of the tilting cylinder is slidably fitted into the recess of the contact cylinder, and the optical fiber tube and the tilting cylinder are tiltably connected to the contact cylinder. ,
When the bulge is fitted into the dent, an intermediate member is provided between the dent and the bulge, and the intermediate member has a hardness higher than that of the dent and the bulge. Fluorescent fiber optic thermometer. With the contact cylinder pressed against the object to be detected, the intermediate member covering either the recess or the bulge and the recess and the other of the bulges are in spherical contact with each other , or the recess and the bulge and the other. The fluorescent optical fiber thermometer according to claim 1, wherein the intermediate members covering each of the bulges are in spherical contact with each other. The invention according to claim 1 or 2, wherein at least the recess in the inside of the contact cylinder is filled with grease, and when the bulge fits into the recess, the grease is interposed between the recess and the bulge. Fluorescent fiber optic thermometer. The fluorescent optical fiber thermometer according to claim 3, further comprising a sealing member that seals a gap between the contact cylinder and the tilting cylinder. The fluorescent optical fiber thermometer according to any one of claims 1 to 4, wherein the outer surface of the contact cylinder is covered with an outer member having a hardness higher than that of the outer surface. The fluorescence according to any one of claims 1 to 5, in which the contact cylinder is pressed against the object to be detected and the bulge is fitted in the recess, and the phosphor is located inside the recess. Optical fiber thermometer. The fluorescent optical fiber thermometer according to any one of claims 1 to 6, wherein the phosphor is covered with a cylinder made of glass, and the cylinder is covered with the tilting cylinder.

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