WO2016068107A1

WO2016068107A1 - Temperature sensor

Info

Publication number: WO2016068107A1
Application number: PCT/JP2015/080182
Authority: WO
Inventors: 雅紀廣中; 元樹佐藤
Original assignee: 株式会社デンソー
Priority date: 2014-10-31
Filing date: 2015-10-27
Publication date: 2016-05-06
Also published as: JP2016090563A; JP6350400B2; DE112015004970T5; DE112015004970B4

Abstract

This temperature sensor (1) includes: a temperature-sensitive element (2) that changes electrical characteristics in accordance with the temperature; a pair of signal lines (21) extending from the temperature-sensitive element (2) toward the back-end side; an insulation tube (3) that allows the pair of signal lines (21) to be inserted thereinto, so as to insulate the pair of signal lines (21); an external tube (4) that covers the insulation tube (3) and the temperature-sensitive element (2); a leading-end holding member (5A) which is provided on the outer circumference of a leading end (31) of the insulation tube (3), and which allows the leading end (31) of the insulation tube (3) to be held to the external tube (4); and a back-end holding member (5B) which is provided on the outer circumference of a back end (32) of the insulation tube (3), and which allows the back end (32) of the insulation tube (3) to be held to the external tube (4). The leading-end holding member (5A) is formed of a non-metallic inorganic fiber.

Description

Temperature sensor

Cross-reference of related applications

This application is based on Japanese Patent Application No. 2014-223263 filed on October 31, 2014 and Japanese Patent Application No. 2015-119661 filed on June 12, 2015. The entire contents of which are hereby incorporated by reference into this application.

The present disclosure relates to a temperature sensor that measures the temperature of a measurement site using a temperature sensitive element.

In a temperature sensor that measures the temperature of exhaust gas or the like flowing through an exhaust pipe of a vehicle, a temperature sensitive element whose electrical characteristics change depending on the temperature is used. In the temperature sensor, a pair of signal wires extending from the temperature sensing element to the rear end side, an insulating tube that holds the pair of signal wires while insulating them, and an outer tube that covers the outer periphery of the insulating tube are provided. . The outer periphery of the insulating tube is held on the outer tube directly or via a filler or the like, and the outer periphery of the rear end is held on the outer tube via an elastic body, a metal mesh, a rubber bush, or the like. Has been.

For example, Patent Document 1 discloses a temperature sensor in which an insulating tube is attached to a cylindrical member by a holding member. The holding member is configured by an elastic body such as a spring or a metal mesh in which metal thin wires are entangled.

JP 2012-93340 A

In recent years, there has been a demand for improved control of turbochargers using temperature sensors due to demand for exhaust gas regulations and high fuel efficiency. For this reason, the temperature sensor is required to have high responsiveness for controlling the turbocharger and high-temperature vibration resistance that can withstand high-temperature and high-vibration environments using the turbocharger.
However, the inventors of the present application, in the background art such as Patent Document 1, etc., when the holding member that holds the insulating tube on the cylindrical member (outer tube) is configured by an elastic body such as a spring, a metal mesh, or the like. Found the following problems. That is, when the environment in which the temperature is measured by the temperature sensor is high, the holding member is thermally deteriorated by heat, and it is difficult to stably hold the insulating tube on the cylindrical member. Furthermore, when vibration due to running of the vehicle is transmitted to the temperature sensor, the holding member is more likely to be thermally deteriorated due to the influence of repeatedly generated stress. The thermal deterioration referred to here is hot relaxation, which means that plastic strain is generated under a low stress within the elastic limit, and the holding member loses holding power. When this thermal sag occurs, when the vibration due to running of the vehicle is transmitted to the temperature sensor, the insulating tube may receive the vibration and break or bend.
In addition, a method of fixing an insulating tube to a cylindrical member with a filler that fixes the temperature sensitive element to the cylindrical member is known. However, when the insulating tube is fixed to the cylindrical member with the filler, the amount of heat transferred from the element through the filler to the insulating tube is large, and the responsiveness of the temperature sensor is lowered.

The present disclosure has been made in view of such a background, and provides a temperature sensor that can improve durability against heat and can stably hold an insulating tube on an outer tube over a long period of time. It is aimed.

In one aspect of the present disclosure, the temperature sensor is
A temperature-sensitive element whose electrical characteristics change with temperature,
A pair of signal lines extending from the thermosensitive element to the rear end side;
An insulating tube that is inserted through the pair of signal lines and insulated from the pair of signal lines;
An outer tube covering the insulating tube and the temperature sensing element;
A tip-side holding member that is provided on the outer periphery of the tip of the insulating tube and holds the tip of the insulating tube on the outer tube;
A rear end holding member provided on an outer periphery of the rear end portion of the insulating tube, and holding the rear end portion of the insulating tube on the outer tube;
With
The said front end side holding member is comprised from the nonmetallic inorganic fiber.

According to said structure, the front end side holding member which hold | maintains the front-end | tip part of an insulating tube to an outer tube is comprised from the nonmetallic inorganic fiber.
Even if the environment measured by the temperature sensor is high temperature, this non-metallic inorganic fiber is hardly deteriorated by heat, and the performance of holding the insulating tube on the outer tube hardly decreases. In particular, the tip-side holding member provided on the outer periphery of the tip of the insulating tube is easily heated to a high temperature. For this reason, the insulating tube can be stably held on the outer tube for a long period of time by configuring the tip side holding member from the non-metallic inorganic fiber.

Further, by holding the insulating tube on the outer tube by the front end side holding member and the rear end side holding member, it is possible to prevent the insulating tube from being cracked or bent due to vibration or the like.
Therefore, according to said structure, durability of the temperature sensor with respect to a heat | fever can be improved, and an insulating tube can be stably hold | maintained to an outer tube over a long period of time.

Also, since the insulating tube can be held on the outer tube by each holding member, it is not necessary to fix the insulating tube to the outer tube with a filler. That is, the amount of filler used can be a small amount for fixing the temperature sensitive element to the outer tube, and a cavity can be provided between the filler and the insulating tube. Thereby, the amount of heat transfer from the temperature-sensitive element to the insulating tube via the filler can be suppressed, and the responsiveness and high-temperature vibration resistance of the temperature sensor can be improved.

Sectional drawing which shows the temperature sensor concerning embodiment. Sectional drawing which shows the front end side part of the temperature sensor concerning embodiment. Sectional drawing which shows the rear-end side part of the temperature sensor concerning embodiment. Explanatory drawing which shows the temperature sensor concerning embodiment attached to the exhaust pipe. Explanatory drawing which shows the state which inserts the insulation pipe | tube with which each holding member was assembled | attached in an outer pipe | tube. Sectional drawing which shows the temperature sensor concerning a 1st modification. Sectional drawing which shows the temperature sensor concerning a 2nd modification. Sectional drawing which shows the temperature sensor concerning a 3rd modification. Sectional drawing which shows the temperature sensor concerning a 4th modification. Sectional drawing which shows the temperature sensor concerning a 5th modification. Sectional drawing which shows the temperature sensor concerning a 6th modification. Sectional drawing which shows the temperature sensor concerning a 7th modification.

As shown in FIG. 1, the temperature sensor 1 according to one embodiment includes a temperature sensitive element 2, a pair of signal wires 21, an insulating tube 3, an outer tube 4, a front end side holding member 5A, and a rear end side holding member 5B. ing. The temperature sensitive element 2 has an electrical characteristic (electrical resistance) that varies depending on the temperature. The pair of signal lines 21 extends from the temperature sensitive element 2 to the rear end side. The insulating tube 3 has a pair of signal lines 21 inserted therethrough and is insulated from the pair of signal lines 21. The insulating tube 3 insulates the pair of signal lines 21 from the outer tube 4. The outer tube 4 is made of metal and is formed in a shape that covers the insulating tube 3 and the temperature sensitive element 2. The distal end side holding member 5 A is provided on the outer periphery of the distal end portion 31 of the insulating tube 3, and holds the distal end portion 31 of the insulating tube 3 on the outer tube 4. The rear end side holding member 5 B is provided on the outer periphery of the rear end portion 32 of the insulating tube 3, and holds the rear end portion 32 of the insulating tube 3 on the outer tube 4. The front end side holding member 5A and the rear end side holding member 5B are made of non-metallic inorganic fibers.

Hereinafter, the temperature sensor 1 of the present embodiment will be described in detail with reference to FIGS.
As shown in FIG. 4, the temperature sensor 1 of the present embodiment is disposed in the exhaust pipe 7 of the vehicle and measures the temperature of the exhaust gas G flowing through the exhaust pipe 7.
An insertion hole 71 for inserting the temperature sensor 1 is formed in the exhaust pipe 7. A female screw part 711 is formed on the front side of the insertion hole 71, and a latching part 712 having a diameter smaller than that of the female screw part 711 is formed on the back side of the insertion hole 71. When the temperature sensor 1 is inserted into the exhaust pipe 7, a rib 43 provided on the outer pipe 4 is hooked on the hooking part 712 of the insertion hole 71, and the outer pipe 4 is put on the female thread part 711. A nipple 44 to be attached to the outer periphery of the nipple is tightened. Then, the rib 43 is brought into close contact with the hooking portion 712 to close the gap between the temperature sensor 1 and the insertion hole 71.

In the present embodiment, the temperature sensitive element 2 is constituted by a thermistor. The temperature sensing element 2 can also be constituted by a resistance temperature detector made of a thermocouple, platinum (Pt) or the like instead of the thermistor. As shown in FIG. 2, the temperature sensitive element 2 is covered with a glass layer 22 for suppressing oxygen reduction deterioration. The temperature sensing element 2 is disposed inside the distal end portion 411 of the outer tube 4 and in a space S formed on the distal end side of the distal end surface 311 of the insulating tube 3. A filler 61 for fixing the temperature-sensitive element 2 to the distal end portion 411 of the outer tube 4 is disposed at the distal end side portion in the space S in a state where a part of the space S is left at the rear end side portion. . The filler 61 contains aggregate particles such as ceramic powder, glass components, and the like.

As shown in FIG. 2, the pair of signal lines 21 protrudes from the distal end surface 311 of the insulating tube 3 toward the distal end side and is connected to the temperature sensing element 2, and after being disposed in the insulating tube 3. And an end portion 214. The distance between the front end side portions 213 of the pair of signal lines 21 is bent from the rear end side portion 214, so that the distance between the rear end side portions 214 of the pair of signal lines 21 is narrower. The front end portion 213 of the pair of signal lines 21 and the rear end portion 214 of the pair of signal lines 21 are formed in parallel to each other. Between the front end side portion 213 and the rear end side portion 214 of the pair of signal lines 21, a tapered portion 215 that connects the two is formed.

The filler 61 covers the entire temperature sensing element 2 and the entire tip end portion 213 of the pair of signal lines 21. When the length from the inner front end surface of the front end portion 411 of the outer tube 4 to the front end surface 311 of the insulating tube 3 is L, the range of the length L1 filled with the filler 61 is the front end portion of the outer tube 4 It can be made into the range of 0.6L or more from the inner front end surface of 411 to the rear end side. However, in order to reduce the amount of heat transfer from the temperature sensing element 2 to the rear end side of the insulating tube 3 or the like, a part of the space S is formed between the rear end position of the filler 61 and the front end surface 311 of the insulating tube 3. To be left behind. Note that if heat transfer from the temperature sensing element 2 to the rear end side of the insulating tube 3 or the like occurs, the responsiveness of the temperature sensor 1 is lowered.

By covering the entire temperature sensing element 2 with the filler 61, the temperature sensing element 2 can be protected from vibrations and the like. Further, by covering the entire distal end portion 213 of the pair of signal lines 21 with the filler 61, the filler 61 is disposed between the distal end portions 213 of the pair of signal lines 21. Contact between the distal end portions 213 can be reliably prevented.
Moreover, in the temperature sensor 1 of this embodiment, the usage amount of the filler 61 can be reduced by holding the insulating tube 3 and the pair of signal lines 21 on the outer tube 4 by the holding

members

5A and 5B.

As shown in FIGS. 2 and 3, the insulating tube 3 is configured by a cylindrical ceramic sintered body having a pair of insertion holes 33 through which the pair of signal lines 21 are inserted. The insulating tube 3 is made of ceramics having high heat resistance such as Al ₂ O ₃ (alumina), ZrO ₂ (zirconia), MgO (magnesia), and the like. Among these ceramics, Al ₂ O ₃ is preferable because of its high strength and good workability. Each signal line 21 is connected to the temperature sensing element 2 and is inserted into each insertion hole 33. Each signal line 21 is made of a heat-resistant material such as, for example, INCONEL601, INCONEL600, Pt, Fe—Cr—Al alloy, Pt—Ir alloy.

Further, an adhesive (for example, a ceramic adhesive such as Aron ceramics) 34 is provided in the gap between the opening portions at both ends of each insertion hole 33. Each signal line 21 is fixed to the insulating tube 3 with an adhesive 34.
The outer tube 4 is connected to the distal end side tube portion 41 covering the distal end side portion of the insulating tube 3 and the temperature sensing element 2 and the rear end side of the distal end side tube portion 41, and the rear end covering the rear end side portion of the insulating tube 3. Side tube portion 42. The distal end portion 411 of the distal end side tube portion 41 is reduced in diameter in accordance with the size of the temperature sensing element 2 at a position closer to the distal end side than the distal end surface 311 of the insulating tube 3.

As shown in FIG. 1, the distal end side holding member 5 A is sandwiched between the outer periphery of the distal end portion 31 of the insulating tube 3 and the inner periphery of the distal end side tube portion 41. It is held by the side tube portion 41. The rear end side holding member 5B is sandwiched between the outer periphery of the rear end portion 32 of the insulating tube 3 and the inner periphery of the rear end side tube portion 42, and the rear end portion 32 of the insulating tube 3 is connected to the rear end side tube. Held in the part 42.

As shown in FIG. 3, in the rear end side pipe portion 42, a rear end side holding member 5 B provided on the outer periphery of the rear end portion 32 of the insulating tube 3, and from the rear end surface of the insulating tube 3 to the rear end side. A pair of lead wires 62 connected to a portion of the pair of signal wires 21 projecting toward and a rubber bush 63 for holding the pair of lead wires 62 in the rear end side pipe portion 42 are disposed. .

The distal end portion 31 of the insulating tube 3 is reduced in diameter at the outer periphery of a portion 412 of the distal end side tube portion 41 located on the outer peripheral side of the distal end side holding member 5A, whereby the distal end side tube portion 41 is interposed via the distal end side holding member 5A. It has been cramped. The rear end portion 32 of the insulating tube 3 is reduced in diameter by reducing the outer periphery of a portion 421 of the rear end side tube portion 42 located on the outer peripheral side of the rear end side holding member 5B, thereby allowing the rear end portion 32 to pass through the rear end side holding member 5B. It is caulked to the end side pipe part 42. The pair of lead wires 62 are caulked to the rear end side pipe portion 42 via the bush 63 by reducing the diameter of the outer periphery of a portion 422 of the rear end side pipe portion 42 located on the outer peripheral side of the bush 63.

Since the insulating tube 3 is caulked to the outer tube 4 via the holding

members

5A and 5B, the maximum static frictional force acting on the insulating tube 3 by the holding

members

5A and 5B acts on the insulating tube 3 by vibration. It becomes larger than the load. The maximum static frictional force is the repulsive force (surface pressure) acting on the holding

members

5A and 5B, the static friction coefficient between the insulating tube 3 and the holding

members

5A and 5B, and the holding

members

5A and 5B and the outer tube. 4 based on the coefficient of static friction between 4 and 4. Thereby, the insulating tube 3 can be stably held in the outer tube 4.

The non-metallic inorganic fibers constituting the holding

members

5A and 5B are ceramic fiber molded bodies formed into a cylindrical shape, a mat shape, or a sheet shape. The molded body of ceramic fiber is excellent in heat resistance. The ceramic fiber is composed of alumina fiber, silica fiber, or the like. The molded body of ceramic fibers can be molded into a predetermined shape by mixing ceramic fibers and any other component such as a binder. Moreover, the ceramic fiber molded body can be formed by collecting ceramic fibers in a cotton shape without using a binder.
The nonmetallic inorganic fibers constituting the holding

members

5A and 5B can be, for example, glass fibers or rock wool, in addition to the ceramic fibers.

The mat-like or sheet-like holding members 5 A and 5 B made of a ceramic fiber molded body can be wound around the insulating tube 3. Further, when the

cylindrical holding members

5A and 5B are used, the insulating tube 3 can be press-fitted into the holding

members

5A and 5B. When the temperature sensor 1 is assembled, as shown in FIG. 5, the insulating tube 3 assembled with the holding members 5 A and 5 B can be inserted into the outer tube 4.

As shown in the figure, when the insulating tube 3 is inserted into the outer tube 4, the holding members 5 A and 5 B slide along the inner periphery of the outer tube 4, so that the insulating tube 3 and the outer tube are inserted. 4 can be improved. Thereby, the assembly | attachment property of the temperature sensor 1 can be improved.
In addition, since the coaxiality between the insulating tube 3 and the outer tube 4 can be easily secured, the distal end side tube portion 41 in which the temperature sensing element 2 is reduced in diameter when the insulating tube 3 is inserted into the outer tube 4. Thus, it is possible to prevent the temperature sensitive element 2 from being cracked during assembly.

Further, each holding

member

5A, 5B can be assembled to the insulating tube 3 via an adhesive (for example, a ceramic adhesive or a nonwoven fabric containing an organic binder). In this case, the holding

members

5A and 5B can be made difficult to be displaced in the axial direction of the insulating tube 3 by the adhesive. Further, the adhesive can be volatilized by heat when the filler 61 in the temperature sensor 1 after assembly is sintered.

Further, the ceramic fiber constituting each holding

member

5A, 5B can contain an expansion material such as vermiculite. The inflating material is contained in the gap between the ceramic fibers. In this case, the expansion material expands due to heat generated when the filler 61 in the temperature sensor 1 after assembly is sintered. And the molded body of the ceramic fiber which comprises each holding

member

5A, 5B expand | swells with an expansion | swelling material, A pressure can be produced in the insulating tube 3 and the outer tube | pipe 4 from each holding

member

5A, 5B. As a result, as shown in FIG. 6, the insulating tube 3 can be connected via the holding

members

5A and 5B without reducing the outer circumference of the outer tube 4 and pressing (caulking) the holding

members

5A and 5B. It can be fixed to the outer tube 4.

In the temperature sensor 1 of the present embodiment, the front end side holding member 5A and the rear end side holding member 5B are formed of a ceramic fiber molded body.
Even if the environment measured by the temperature sensor 1 is high temperature, the ceramic fiber is hardly thermally deteriorated, and the performance of holding the insulating tube 3 on the outer tube 4 hardly decreases. Therefore, the insulating tube 3 can be stably held on the outer tube 4 over a long period of time by configuring the holding

members

5A and 5B from ceramic fibers.

In the exhaust pipe of the vehicle, heating and cooling are repeated according to the combustion cycle of the engine, and the outer pipe 4 in the temperature sensor 1 is repeatedly expanded and contracted under the influence of heat. The degree of expansion / contraction of the metal outer tube 4 is larger than the degree of expansion / contraction of the insulating tube 3 and the holding

members

5A, 5B. And when the outer tube | pipe 4 expand | swells, the condition where it will be easy to make a clearance gap between each holding

member

5A, 5B and the outer tube | pipe 4 will generate | occur | produce.

Even in this situation, the density of filling the ceramic fiber compacts constituting the holding

members

5A and 5B between the insulating tube 3 and the outer tube 4 is increased so that the outer tube 4 expands. Thus, a restoring force can be applied to each holding

member

5A, 5B. The density here means the filling density, that is, the density of the holding

members

5A and 5B after the temperature sensor 1 is assembled. Thereby, the state in which the insulating tube 3 is held by the holding members 5 A and 5 B can follow the expansion of the outer tube 4. That is, it is possible to prevent gaps between the holding

members

5A and 5B and the outer tube 4 even at high temperatures. As a result, the insulating tube 3 can be stably held on the outer tube 4 over a long period of time even in an environment with large temperature fluctuations.

Further, it is necessary to supply oxygen from the rear end side of the temperature sensor 1 to the temperature sensing element 2 in order to prevent reduction degradation at a high temperature of the temperature sensing element 2 to the temperature sensing element 2 constituted by the thermistor. is there. At this time, since each holding

member

5A, 5B is formed of a ceramic fiber molded body, oxygen can be easily supplied to the temperature sensing element 2 through each holding

member

5A, 5B.

Further, by holding the insulating tube 3 on the outer tube 4 by the front end side holding member 5A and the rear end side holding member 5B, the insulating tube 3 can be prevented from being broken by vibration or the like. Further, as shown in FIG. 7, the vibration stress acting on the insulating tube 3 is reduced by increasing the axial length of each holding

member

5A, 5B and increasing the area of each holding

member

5A, 5B assembled to the insulating tube 3. can do.
Therefore, according to the temperature sensor 1 of the present embodiment, durability against heat can be improved, and the insulating tube 3 can be stably held on the outer tube 4 over a long period of time.

In addition, the insulation tube 3 is held on the outer tube 4 by the holding

members

5A and 5B to prevent the insulation tube 3 from cracking when the temperature sensor 1 is assembled, and to reduce the amount of filler 61 used. A decrease in responsiveness of the temperature sensor 1 can be prevented.

Further, the relationship between the thickness t1 of the holding

members

5A and 5B and the clearance t2 between the insulating tube 3 and the outer tube 4 (front end side tube portion 41, rear end side tube portion 42) is t1> t2. Is preferred. Thereby, the coaxiality of the insulating tube 3 and the outer tube 4 can be improved, and the insulating tube 3 can be stably held by the outer tube 4. However, if the thickness t1 of the holding

members

5A and 5B is too large, the temperature sensor 1 is hindered and the holding force (surface pressure) acting on the holding

members

5A and 5B becomes too high, and the holding member 5A. , 5B may cause heat sink. Therefore, the relationship between the thickness t1 and the clearance t2 is more preferably 2 × t2> t1> t2.

If the thickness t1 of the holding

members

5A and 5B is smaller than the clearance t2, the insulating tube 3 cannot be sufficiently held, and the insulating tube 3 may crack when vibration stress is applied to the insulating tube 3. is there.
For example, when the clearance between the insulating tube 3 and the outer tube 4 is about 1 mm, sheet-

like holding members

5A and 5B having a thickness of about 1.5 mm can be used. Then, by press-fitting the insulating tube 3 around which the holding

members

5A and 5B are wound into the outer tube 4, the coaxiality between the insulating tube 3 and the outer tube 4 is improved, and the assembling property of the temperature sensor 1 is improved. be able to.

Further, as shown in FIG. 8, the insulating tube 3 can be held on the outer tube 4 by holding

members

5A, 5B, 5C provided at three locations in the longitudinal direction. In this case, the holding member 5 C provided at the intermediate position can also be compressed by reducing the outer diameter of the portion 413 of the distal end side tube portion 41. By increasing the number of places where the insulating tube 3 is held by the holding

members

5A, 5B, and 5C, displacement generated in the insulating tube 3 due to vibration can be reduced, and vibration stress acting on the insulating tube 3 can be reduced.

Moreover, as shown in FIG. 9, the front end side holding member 5A and the rear end side holding member 5B can be configured by a holding member 5 in which these are integrated. In this case, the entire length of the insulating tube 3 can be held by the outer tube 4 by the holding member 5. In this case, since the entire insulating tube 3 can be supported by the holding member 5, the insulating tube 3 can be stably held on the outer tube 4 over a long period of time.

FIGS. 1 to 9 show the case where the signal line 21 of the temperature sensing element 2 is constituted by a lead wire drawn out from the temperature sensing element 2.
In addition to this, as shown in FIG. 10, the signal line 21 is a laser produced by abutting a lead portion 211 drawn from the temperature sensing element 2 with a lead wire member 212 protruding from the insertion hole 33 of the insulating tube 3. It can also be set as the structure welded. As shown in FIG. 11, the signal line 21 is laser-welded by superposing a lead portion 211 drawn from the temperature sensing element 2 and a lead wire member 212 protruding from the insertion hole 33 of the insulating tube 3. It can also be configured. In this case, the entire portion of the lead portion 211 that is not overlapped with the lead wire member 212 is covered with the filler 61.

Further, as shown in FIG. 12, the insulating tube 3 may be a sheath pin. In this case, the sheath pin is constituted by a metal hollow tube 35 and an insulating filling powder 36 filled in the hollow tube 35 through which the pair of signal wires 21 (lead wire members 212) are inserted. . In this case, the pair of signal wires 21 (lead wire members 212) and the outer tube 4 can be insulated by the insulating filling powder 36. Also in this case, the same effect as the case where the insulating tube 3 is comprised by the ceramic sintered compact can be acquired.

In this case, the lead portions 211 constituting the pair of signal lines 21 can be made of, for example, Pt, Pt—Ir alloy, Pt—Rh alloy, etc., and the lead wires constituting the pair of signal lines 21 The member 212 can be composed of, for example, INCONEL601, INCONEL600, Fe—Cr—Al alloy, or the like. The filling powder 36, for example, can be constituted by MgO (magnesia powder) and SiO ₂ (silica powder). Also in the temperature sensor 1 of FIG. 12, the lead part 211 drawn out from the temperature sensing element 2 and the pair of lead wire members 212 can be overlapped and laser-welded. In this case, the entire welded portion between the lead portion 211 and the lead wire member 212 is covered with the filler 61.

Note that the present disclosure is not limited to the above-described embodiments and modifications, and it is needless to say that various modifications can be made without departing from the gist of the present disclosure.

Claims

A temperature sensitive element (2) whose electrical characteristics change with temperature,
A pair of signal lines (21) extending from the temperature sensing element (2) to the rear end side;
An insulating tube (3) that is inserted through the pair of signal lines (21) and insulated from the pair of signal lines (21);
An outer tube (4) covering the insulating tube (3) and the temperature sensing element (2);
A distal-side holding member (5A) provided on the outer periphery of the distal end portion (31) of the insulating tube (3) and retaining the distal end portion (31) of the insulating tube (3) on the outer tube (4);
A rear end side holding member (5B) provided on the outer periphery of the rear end portion (32) of the insulating tube (3) and holding the rear end portion (32) of the insulating tube (3) to the outer tube (4). And comprising
The said front end side holding member (5A) is a temperature sensor (1) comprised from the nonmetallic inorganic fiber.
The temperature sensor (1) according to claim 1, wherein the rear end side holding member (5B) is made of a non-metallic inorganic fiber.
3. The temperature sensor (1) according to claim 1 or 2, wherein the non-metallic inorganic fiber is a ceramic fiber molded body formed into a mat or sheet.
The insulating tube (3) is formed of a ceramic sintered body having a pair of insertion holes (33) through which the pair of signal lines (21) are inserted. Temperature sensor (1).
The insulating tube (3) includes a metal hollow tube (35) and an insulating filling powder (36) filled in the hollow tube (35) through which the pair of signal wires (21) are inserted. The temperature sensor (1) according to any one of claims 1 to 3, comprising:
The temperature sensing element (2) is a space (S) formed in the distal end side (311) of the insulating tube (3) inside the distal end portion (411) of the outer tube (4). )
A filler for fixing the temperature sensing element (2) to the tip end portion (411) in a state where a part of the space (S) is left in the rear end side portion in the tip end side portion in the space (S). The temperature sensor (1) according to any one of claims 1 to 5, wherein (61) is arranged.
The distance between the tip side portions (213) of the pair of signal lines (21) connected to the temperature sensing element (2) is the rear of the pair of signal lines (21) disposed in the insulating tube (3). It is narrower than the distance between the end portions (214),
The temperature sensor (1) according to claim 6, wherein the filler (61) covers the entirety of the temperature sensitive element (2) and the entire distal end portion (213) of the pair of signal lines (21). .