JP6234755B2 - Temperature sensor - Google Patents

Description

  The present invention relates to a temperature sensor including a pair of thermocouple wires and a temperature measuring contact portion formed by joining the tips of the pair of thermocouple wires to each other.

  A temperature sensor is known that includes a pair of thermocouple wires and a temperature measuring contact portion formed by joining the tips of the pair of thermocouple wires to each other (see, for example, Patent Document 1). The temperature sensor described in Patent Document 1 includes an insulating soot tube and an outer cylinder. The insulated soot pipe passes through each of the pair of thermocouple wires in a state of being insulated from each other. The outer cylinder accommodates the temperature measuring contact portion.

Japanese Utility Model Publication No. 56-174032

  In the temperature sensor described in Patent Document 1, the temperature measuring contact portion is separated from the insulating rod and the outer cylinder. In the temperature sensor having such a configuration, when the temperature measuring contact portion is formed by welding the tips of the pair of thermocouple wires, it is difficult to control the welding conditions, and the temperature measuring contact portion is arranged at a specified position. Is difficult.

  The present invention has a pair of thermocouple wires and a temperature measuring contact portion formed by joining the tips of the pair of thermocouple wires to each other. An object of the present invention is to provide a temperature sensor having a configuration that is easy to manufacture without impairing the above.

The temperature sensor according to one aspect of the present invention includes a pair of thermocouple wires, a temperature measuring contact portion formed by joining tips of the pair of thermocouple wires to each other, and the pair of thermocouple elements. In a temperature sensor comprising: an insulated soot pipe that passes through each of the wires in an insulated state; and an outer cylinder that is closed at the tip end and that is formed in a bottomed cylindrical shape extending in the axial direction. A first housing part that houses at least a part of the insulating soot tube, and a width in at least a part of the first housing part that is perpendicular to the axial direction than the first housing part. A second accommodating portion that accommodates the temperature measuring contact portion, and is provided at a distal end portion of the insulated soot tube, at least its own distal end portion is accommodated in the second accommodating portion, and the own distal end portion is comprising a contact member in contact with the rear end of the measuring junction portion, the absolute Porcelain bushing is in contact with the second housing portion that is positioned.

As a configuration in which the temperature measuring contact portion is stably arranged at a predetermined position, a configuration in which the temperature measuring contact portion is brought into contact with the distal end portion of the insulating rod tube is conceivable. However, in the case of this configuration, there is a limit to reducing the diameter (width) of the insulating soot tube from the viewpoint of strength and the like. The distance becomes larger than before, and the response sensitivity of the temperature sensor is impaired. Therefore, in the temperature sensor of this aspect, a contact member is provided at the tip of the insulating soot tube. When the temperature sensor forms a temperature measuring contact portion by welding the tips of a pair of thermocouple wires, the welded wires come into contact with the tips of the contact members and solidify. That is, the temperature sensor of this aspect can form the temperature measuring contact portion at a position where the rear end portion of the temperature measuring contact portion contacts the tip end portion of the contact member. The temperature sensor can easily form the temperature measuring contact portion at a specified position while ensuring the strength of the insulating rod. Since the temperature measuring contact portion is accommodated in the second accommodating portion, the distance between the temperature measuring contact portion and the outer cylinder is made smaller than when the temperature measuring contact portion is accommodated in the first accommodating portion. Is possible. Therefore, the temperature sensor can exhibit high responsiveness stably. The temperature sensor can position an insulated soot pipe with respect to an outer cylinder by making an insulated soot pipe contact with a 2nd accommodating part.

  In the temperature sensor according to this aspect, the front end portion of the contact member may be recessed on the rear end side and have a concave portion that contacts the rear end portion of the temperature measuring contact portion. The temperature sensor in this case can increase the contact area between the contact member and the rear end portion of the temperature measuring contact portion as compared with the case where the front end portion of the contact member is planar. Therefore, the temperature sensor can reduce the possibility that the temperature measuring contact portion is damaged by vibration.

  In the temperature sensor of this aspect, each of the pair of thermocouple wires may contact the contact member at two or more points. In this case, the temperature sensor reduces the possibility that the pair of thermocouple wires is damaged by vibration compared to the case where each of the pair of thermocouple wires is in contact with the contact member at one point or less. Can do.

  In the temperature sensor according to this aspect, the length in the axial direction from the tip of the insulating rod tube to the inner bottom portion of the outer cylinder is L, and the length in the axial direction from the tip of the insulating rod tube to the temperature measuring contact portion Where M is L / 2 or more. In this case, the temperature sensor can reduce the distance between the temperature measuring contact portion and the inner bottom portion of the outer cylinder as compared with the case where M is less than L / 2, and the temperature measuring contact portion can be damaged by vibration. The response sensitivity can be further improved while reducing the performance.

  In the temperature sensor of this aspect, the temperature measuring contact portion and the outer cylinder may be separated from each other by the diameter of the thermocouple wire. The temperature sensor in this case is short-circuited by the contact between the temperature measuring contact portion and the outer cylinder, compared to the case where the distance between the temperature measuring contact portion and the outer cylinder is less than the diameter of the pair of thermocouple wires. The possibility can be reduced.

2 is a partial longitudinal sectional view of the temperature sensor 1. FIG. 3 is an enlarged partial longitudinal sectional view of a tip portion of a temperature sensor 1. FIG. 3 is a perspective view of an insulating soot tube 30. FIG. It is a vertical fragmentary sectional view of the temperature sensor 101 of a modification.

  Hereinafter, a temperature sensor 1 which is an embodiment of the present invention will be described with reference to the drawings. The drawings to be referred to are used for explaining technical features that can be adopted by the present invention. The configuration of the sensor described is not intended to be limited to that, but merely an illustrative example. In the following description, the vertical direction and the horizontal direction in FIGS. 1 and 2 will be described as the vertical direction and the horizontal direction of the temperature sensor 1, respectively. 1 and 2 will be described as the front side and the back side of the temperature sensor 1, respectively. 1 and 2 will be described as the rear end side of the temperature sensor 1, and the lower side of FIGS. 1 and 2 will be described as the front end side of the temperature sensor 1. 1 and 2, the axis of the temperature sensor 1 is illustrated by the axis AX. The axis AX direction is the longitudinal direction of the temperature sensor 1 and corresponds to the vertical direction in FIGS. Of the directions perpendicular to the axis AX, the direction starting from the axis AX is referred to as the radial direction. A direction around the axis AX around the axis AX is referred to as a circumferential direction.

  The configuration of the temperature sensor 1 of the first embodiment will be described with reference to FIGS. 1 to 3. For example, the temperature sensor 1 is attached to an exhaust pipe for discharging exhaust gas discharged from an engine of an automobile (not shown) to the outside of the vehicle. The temperature sensor 1 includes an outer cylinder 10, a temperature measuring contact portion 21, a pair of thermocouple wires 23 and 24, an insulating insulator tube 30, a contact member 40, a pair of compensating conductors 25 and 26, and a nut member 50. The joint member 60, the shield tube 70, and the seal member 80 are the main constituents.

  The outer cylinder 10 is a member formed in a bottomed cylindrical shape extending in the axis AX direction with the tip 13 closed. The outer cylinder 10 is formed of a metal having corrosion resistance (for example, a stainless alloy). A radially projecting flange 19 is fixed to the outer peripheral surface 15 near the lower side of the center in the vertical direction of the outer cylinder 10 by welding. The outer cylinder 10 includes a first housing part 11 and a second housing part 12. The 1st accommodating part 11 accommodates at least one part of the insulated soot pipe 30 mentioned later. The second accommodating portion 12 is disposed on the distal end side of the first accommodating portion 11 and has a width in at least a part of the direction perpendicular to the direction of the axis AX smaller than that of the first accommodating portion 11. At least a part of the direction perpendicular to the axis AX direction may be a direction perpendicular to the axis AX direction as long as the direction used for the comparison is the same in the first accommodation part 11 and the second accommodation part 12. The width is determined based on the inner peripheral surface 14 of the outer cylinder 10.

  In the temperature sensor 1 of the present embodiment, the cross section perpendicular to the axis AX of the first housing portion 11 has a circular shape with the axis W as the center and a diameter of W1. Similarly, the cross section perpendicular to the axis AX of the second accommodating portion 12 is a circle whose center is the axis AX and whose diameter is the length W2. The 2nd accommodating part 12 of this embodiment is a shape (taper shape) whose width | variety is so narrow that the front end side. Therefore, the length W2 varies depending on the position in the axis AX direction. Each length W2 is shorter than the length W1. The second accommodating portion 12 is smaller in width in all directions perpendicular to the axis AX direction than the first accommodating portion 11. The second accommodating portion 12 accommodates the temperature measuring contact portion 21.

  The temperature measuring contact portion 21 is formed by joining the tips of a pair of thermocouple wires 23 and 24 to each other. The temperature measuring contact portion 21 is formed into a spherical shape by, for example, tungsten-inert gas (TIG) welding or laser welding which is a kind of welding method using electricity. The thermocouple wire 23 is a round wire having a diameter of 0.3 mm to 0.65 mm formed of NiSi and the thermocouple wire 24 of NiCrSi. In the present embodiment, the temperature measuring contact portion 21 and the outer cylinder 10 are separated from each other by the diameter of the thermocouple wires 23 and 24.

  The pair of compensating conductors 25 and 26 are connected to the rear ends of the pair of thermocouple wires 23 and 24, respectively. The compensating conductor 25 is made of NiSi, and the compensating conductor 26 is made of NiCrSi, and each has a thermoelectromotive force characteristic substantially equivalent to that of the pair of thermocouple wires 23 and 24. The pair of compensating conductors 25 and 26 are stranded wires for taking out electrical signals. The pair of compensating lead wires 25 and 26 are led out of the temperature sensor 1 from the rear end of the temperature sensor 1.

  The insulated soot tube 30 is a cylindrical member that is formed of a ceramic insulator and extends in the direction of the axis AX. The insulating soot tube 30 has a pair of holes 31 and 32 extending in the direction of the axis AX. As shown in FIG. 1, the insulating rod 30 holds each of the pair of thermocouple wires 23 and 24 through the pair of holes 31 and 32 while being insulated from each other. At least a part of the insulating soot tube 30 is accommodated in the first accommodating portion 11 of the outer cylinder 10. In this embodiment, the rear end side of the insulated rod 30 is accommodated in a joint member 60 described later. In the temperature sensor 1 of the present embodiment, the cross section perpendicular to the axis AX of the insulating rod 30 is a circle having the axis W as the center and a diameter W3 (for example, 3 mm to 5 mm). The insulated soot tube 30 includes a distal end surface 33 at the distal end portion 35. The distal end surface 33 extends perpendicular to the axis AX direction. The length W <b> 3 is longer than the length W <b> 2 of the portion on the distal end side of the distal end surface 33 of the insulating rod 30. An outer periphery 34 (see FIG. 3) of the distal end surface 33 is in contact with the second housing portion 12. Thereby, the insulating soot tube 30 is positioned with respect to the outer cylinder 10.

  The contact member 40 is provided at the distal end portion 35 of the insulating rod tube 30 and extends in the axis AX direction. The contact member 40 of the present embodiment is a quadrangular columnar member that extends from the distal end surface 33 of the insulating rod 30 toward the distal end side in the axis AX direction. The contact member 40 is formed integrally with the insulating soot tube 30. The contact member 40 has at least a tip portion 41 of the contact member 40 housed in the second housing portion 12. As shown in FIG. 3, the contact member 40 is provided at a position between the pair of holes 31 and 32 on the distal end surface 33. The length N in the front-rear direction of the contact member 40 is longer than the diameter of the pair of holes 31 and 32. The length P in the left-right direction of the contact member 40 is, for example, 0.2 mm to 0.5 mm.

  As shown in FIGS. 1 and 2, the front end portion 41 of the contact member 40 is in contact with the rear end portion 22 of the temperature measuring contact portion 21. Specifically, the front end portion 41 of the contact member 40 has a concave portion 42 that is recessed toward the rear end side. As shown in FIG. 3, the concave portion 42 of the present embodiment is formed in a groove shape extending in the front-rear direction and having an inverted U shape when viewed from the front. The recess 42 is in contact with the rear end portion 22 of the temperature measuring contact portion 21. The length in the axis AX direction from the distal end surface 33 of the insulating rod 30 to the inner bottom portion 16 of the outer cylinder 10 is L, and the length in the axis AX direction from the distal end surface 33 of the insulating rod 30 to the temperature measuring contact portion 21 is M. In this case, M is L / 2 or more. In the direction of the axis AX, the distance between the temperature measuring contact portion 21 and the inner bottom portion 16 of the outer cylinder 10 is shorter than the distance between the temperature measuring contact portion 21 and the distal end surface 33 of the insulating rod 30. .

  As shown in FIG. 1, the nut member 50 is a cylindrical member having a hole 51 extending in the direction of the axis AX, and is fitted to the outer peripheral surface 15 near the center in the vertical direction of the outer cylinder 10. The nut member 50 is disposed so as to be movable with respect to the outer peripheral surface 15 near the center in the vertical direction of the outer cylinder 10. The nut member 50 includes a screw cylinder portion 53 and a polygonal portion 54. A thread for fastening the temperature sensor 1 to a mounting hole (screw hole) in a manifold portion of an exhaust pipe (not shown) is formed on the outer peripheral surface of the screw cylinder portion 53. A portion closer to the distal end of the outer peripheral surface of the screw cylinder portion 53 is formed in a shape (tapered) having a narrower width toward the distal end side. The polygonal part 54 has a hook-like shape protruding in the radial direction on the rear end side of the screw cylinder part 53. When the temperature sensor 1 is fastened and fixed to the mounting hole (screw hole), the nut member 50 comes into contact with the rear end surface of the flange 19 of the outer cylinder 10. Thereby, the nut member 50 is positioned with respect to the outer cylinder 10.

  The joint member 60 is a cylindrical member that is formed of a metal (for example, a stainless alloy) and extends in the direction of the axis AX. The outer cylinder 10 and the joint member 60 are arranged coaxially. The joint member 60 and the outer cylinder 10 are joined at the welded portion 61. The welded portion 61 is configured so that the joint member 60 and the outer cylinder 10 are connected to the outer peripheral surface side of the joint member 60 in a state where the outer peripheral surface on the rear end side of the outer tube 10 and the inner peripheral surface on the front end side of the joint member 60 overlap each other. And is welded over the circumferential direction. The joint member 60 accommodates the rear end side of the pair of thermocouple wires 23 and 24 and the front end side of the pair of compensation conducting wires 25 and 26.

  The shield tube 70 is a cylindrical member that is formed of SUS steel and extends in the direction of the axis AX. The shield tube 70 accommodates the rear end side of the seal member 80 and the rear end sides of the pair of compensating conductors 25 and 26 therein. The joint member 60 and the shield tube 70 are disposed coaxially. The distal end portion of the shield tube 70 is inserted into the cylindrical hole of the joint member 60.

  The seal member 80 is a cylindrical member made of heat-resistant rubber that extends in the direction of the axis AX. The seal member 80 holds the pair of compensating conductors 25 and 26 covered with an insulating covering material through the inside. The compensating conductors 25 and 26 are drawn from the inside of the joint member 60 toward the outside while penetrating the inside of the seal member 80. The seal member 80 is caulked and fixed by the joint member 60 at the first caulking portion 65, and is caulked and fixed by the joint member 60 and the shield tube 70 at the second caulking portion 66. The first caulking portion 65 is on the tip side of the second caulking portion 66.

  In the temperature sensor 1 of the above embodiment, the outer cylinder 10, the first housing part 11, and the second housing part 12 correspond to the outer cylinder, the first housing part, and the second housing part of the present invention, respectively. The temperature measuring contact 21 and the pair of thermocouple wires 23 and 24 correspond to the temperature measuring contact and the pair of thermocouple wires of the present invention, respectively. The insulated soot tube 30, the contact member 40, and the recess 42 respectively correspond to the insulated soot tube, the contact member, and the recessed portion of the present invention.

  In the temperature sensor 1, the contact member 40 is disposed on the distal end side of the insulating rod 30. In the temperature sensor 1, when the temperature measuring contact portion 21 is formed by welding the tips of the pair of thermocouple wires 23 and 24, the welded strand contacts the tip portion 41 of the contact member 40 and solidifies. . That is, the temperature sensor 1 can form the temperature measuring contact portion 21 at a position where the rear end portion 22 of the temperature measuring contact portion 21 contacts the tip end portion 41 of the contact member 40. The temperature sensor 1 can easily form the temperature measuring contact portion 21 at a predetermined position while ensuring the strength of the insulating rod 30. Since the temperature measuring contact 21 is accommodated in the second accommodating portion 12, the temperature measuring contact 21 is located between the temperature measuring contact 21 and the outer cylinder 10 as compared with the case where the temperature measuring contact 21 is accommodated in the first accommodating portion 11. It is possible to reduce the distance. Therefore, the temperature sensor 1 can exhibit high responsiveness stably.

  The rear end portion 22 of the temperature measuring contact portion 21 is in contact with the concave portion 42 of the contact member 40. Even if the temperature sensor 1 receives a relatively strong vibration, the temperature measuring contact portion 21 is unlikely to swing in a direction perpendicular to the direction of the axis AX, and breakage of the temperature measuring contact portion 21 can be suppressed.

  With reference to FIG. 4, the temperature sensor 101 of 2nd embodiment is demonstrated. In FIG. 4, members having the same configuration as that of the temperature sensor 1 of the first embodiment are given the same reference numerals and description thereof is omitted. As shown in FIG. 4, the temperature sensor 101 of the second embodiment and the temperature sensor 1 of the first embodiment are different from each other in the outer cylinder 110 and the contact member 140, and the other configurations are the same. Hereinafter, the outer cylinder 110 and the contact member 140 of the temperature sensor 101 will be described.

  The outer cylinder 110 is a bottomed cylindrical member extending in the direction of the axis AX and having a tip 117 closed. The outer cylinder 110 is formed of a metal having corrosion resistance (for example, a stainless alloy). A flange 119 protruding in the radial direction is fixed to the outer peripheral surface of the outer cylinder 10 by welding. The outer cylinder 110 includes a first housing part 111 and a second housing part 112. The first accommodating portion 111 accommodates at least a part of the insulating soot tube 30. The second accommodating portion 112 is disposed on the distal end side with respect to the first accommodating portion 111 and has a width in at least a part of the direction perpendicular to the direction of the axis AX smaller than that of the first accommodating portion 111. At least a part of the direction perpendicular to the axis AX direction may be a direction perpendicular to the axis AX direction as long as the direction used for comparison is the same in the first housing part 111 and the second housing part 112. The width is determined based on the inner peripheral surface 118 of the outer cylinder 110.

  In the temperature sensor 101 of the present embodiment, the cross section perpendicular to the axis AX of the first housing portion 111 has a circular shape with the axis W as the center and a diameter of W11. Similarly, the cross section perpendicular to the axis AX of the second housing portion 112 is a circle having the axis W as the center and a diameter of W12. The second accommodating portion 112 of the present embodiment includes a step portion 113, a cylindrical portion 114, and a tip portion 115. The step portion 113 is formed in a shape (tapered shape) that is narrower toward the tip side. The tip portion 115 is formed in a hemispherical shape. In the step part 113 and the front-end | tip part 115, length W12 changes according to the position of an axis line AX direction. The cylindrical part 114 is a cylindrical part that connects the step part 113 and the tip part 115. In the cylindrical portion 114, the length W12 is the same regardless of the position in the axis AX direction. Each length W12 is shorter than the length W11. The second accommodating portion 112 is smaller in width in all directions perpendicular to the axis AX direction than the first accommodating portion 111. The second accommodating portion 112 accommodates the temperature measuring contact portion 21. The outer periphery 34 (see FIG. 3) of the distal end surface 33 of the insulating soot tube 30 abuts on the step portion 113 of the second housing portion 112. Thereby, the insulating soot tube 30 is positioned with respect to the outer cylinder 110. In the present embodiment, the temperature measuring contact portion 21 and the outer cylinder 110 are separated from each other by the diameter of the thermocouple wires 23 and 24.

  The contact member 140 is provided at the distal end portion 35 of the insulating rod 30 and extends in the direction of the axis AX. The contact member 140 is a member having an isosceles trapezoidal shape when viewed from the front and extending from the distal end surface 33 of the insulating rod 30 to the distal end side in the axis AX direction. The contact member 140 is formed integrally with the insulating soot tube 30. The pair of thermocouple wires 23 and 24 are respectively disposed along the left and right side surfaces of the contact member 140. That is, the pair of thermocouple wires 23 and 24 are in contact with the contact member 140 at two or more points. At least the front end portion 141 of the contact member 140 is accommodated in the second accommodating portion 112, and the front end portion 141 contacts the rear end portion 22 of the temperature measuring contact portion 21. The front end portion 141 of the contact member 140 has a concave portion 142 that is recessed toward the rear end side. The recessed part 142 of this embodiment is formed in the front-end | tip part 141 of the contact member 40 in the reverse U shape of front view. The recess 142 is in contact with the rear end portion 22 of the temperature measuring contact portion 21. The length in the axis AX direction from the distal end surface 33 of the insulating rod 30 to the inner bottom portion 116 of the outer cylinder 110 is L, and the length in the axis AX direction from the distal end surface 33 of the insulating rod 30 to the temperature measuring contact portion 21 is M. In this case, M is L / 2 or more. In the direction of the axis AX, the distance between the temperature measuring contact portion 21 and the inner bottom portion 116 of the outer cylinder 110 is shorter than the distance between the temperature measuring contact portion 21 and the distal end surface 33 of the insulating rod 30. .

  In the temperature sensor 101 of the above embodiment, the outer cylinder 110, the first housing part 111, and the second housing part 112 correspond to the outer cylinder, the first housing part, and the second housing part of the present invention, respectively. The temperature measuring contact 21 and the pair of thermocouple wires 23 and 24 correspond to the temperature measuring contact and the pair of thermocouple wires of the present invention, respectively. The insulated soot tube 30, the contact member 140, and the recessed part 142 are respectively corresponded to the insulated soot pipe, the contact member, and the recessed part of this invention.

  In the temperature sensor 101, in addition to the same effects as those of the temperature sensor 1, a pair of thermocouple elements is compared to a case where the number of portions where each of the pair of thermocouple wires 23 and 24 contacts the contact member 140 is one point or less. The possibility that the wires 23 and 24 are damaged by vibration can be reduced.

  The temperature sensor of the present invention is not limited to the embodiment described in detail above, and various modifications may be made without departing from the gist of the present invention. For example, the following modifications (A) to (C) may be added.

  (A) The configuration of the outer cylinder 10 may be changed as appropriate. For example, the outer cylinder 10 and the joint member 60 may be integrally formed. The cross-sectional shape of the outer cylinder 10 in the direction perpendicular to the axis AX direction may be appropriately changed such as an elliptical shape. The second accommodating portion 12 only needs to accommodate the temperature measuring contact portion 21 having a width in at least a part of the direction perpendicular to the axis AX direction smaller than that of the first accommodating portion 11. Therefore, for example, the cross-sectional shape of the first housing portion in the direction perpendicular to the axis AX direction is elliptical, and at least part of the cross-sectional shape of the second housing portion in the direction perpendicular to the axis AX direction is circular. Also good.

  (B) The configuration of the insulating rod 30 may be changed as appropriate. The cross-sectional shape of the insulating rod 30 in the direction perpendicular to the axis AX direction may be appropriately changed such as an elliptical shape. The tip of the insulating soot tube 30 may not be a surface perpendicular to the axis AX. The boundary between the insulating rod 30 and the contact member 40 may be unclear. The insulated soot tube 30 and the contact member 40 may be formed separately. The outer periphery 34 (see FIG. 3) of the distal end surface 33 of the insulating rod 30 may not be in contact with the second accommodating portion 12 (112). The material, cross-sectional shape, and the like of the pair of thermocouple wires 23 and 24 may be changed as appropriate. The material and cross-sectional shape of the pair of compensating conductors 25 and 26 may be changed as appropriate.

  (C) The shape and size of the contact member 40 may be changed as appropriate. More specifically, the shape of the contact member 40 may be a polygonal column, a cylinder, or a cone. On the side surface of the contact member 40, a groove in which each of the pair of thermocouple wires 23 and 24 can be contacted linearly or in a planar shape may be formed. In this way, the temperature sensor increases the contact area between the thermocouple wires 23 and 24 and the contact member 40 as compared with the case where no groove is provided, and the pair of thermocouple wires 23 and 24 are caused by vibration. The possibility of breakage can be reduced. The length in the axis AX direction from the distal end surface 33 of the insulating rod 30 to the inner bottom portion 16 of the outer cylinder 10 is L, and the length in the axis AX direction from the distal end surface 33 of the insulating rod 30 to the temperature measuring contact portion 21 is M. In this case, M may be less than L / 2, but M is preferably L / 3 or more. In the axis AX direction, even if the distance between the temperature measuring contact portion 21 and the distal end surface 33 of the insulating rod 30 is equal to or less than the distance between the temperature measuring contact portion 21 and the inner bottom portion 16 of the outer cylinder 10. Good. The temperature measuring contact portion 21 and the outer cylinder 10 only need to be separated from each other. The shape of the concave portion 42 of the contact member 40 is, for example, a concave shape in which the concave portion 42 is hemispherically recessed toward the rear end side, a concave shape in a reverse V shape when viewed from the front, and a groove shape extending in the direction connecting the holes 31 and 32. Etc., may be changed as appropriate. The contact member 40 may not include the recess 42. Depending on the shape of the tip portion 41 of the contact member 40, the shape of the temperature measuring contact portion 21 may be changed. The contact member 40 only needs to be provided at the distal end portion 35 of the insulating soot tube 30, and may not be provided between the pair of holes 31 and 32.

DESCRIPTION OF SYMBOLS 1,101 Temperature sensor 10, 110 Outer cylinder 11, 111 1st accommodating part 12, 112 2nd accommodating part 13 Tip 16 Inner bottom part 21 Temperature measuring contact part 22 Rear end part 23, 24 Thermocouple strand 30 Insulating rod 40, 140 Contact member 41, 141 Tip 42, 142 Recess

Claims (5)

A pair of thermocouple wires;
A temperature measuring contact portion formed by joining the tips of each of the pair of thermocouple wires to each other;
Each of the pair of thermocouple strands, insulated insulator pipes that pass through the interior in a state of being insulated from each other;
An outer cylinder formed in a bottomed cylindrical shape extending in the axial direction with the distal end closed;
In a temperature sensor comprising:
The outer cylinder is
A first housing part for housing at least a part of the insulated soot tube;
A second accommodating portion that is disposed on the tip side of the first accommodating portion, and has a width in at least a part of the direction perpendicular to the axial direction smaller than that of the first accommodating portion, and accommodates the temperature measuring contact portion; Including
Provided at the distal end portion of the insulated soot tube, at least its distal end portion is accommodated in the second accommodating portion, and the distal end portion of the own is in contact with the rear end portion of the temperature measuring contact portion ,
The insulating porcelain bushing, a temperature sensor, characterized that you have been positioned in contact with the second housing part.   The temperature sensor according to claim 1, wherein the front end portion of the contact member has a recess that is recessed toward a rear end side and that contacts the rear end portion of the temperature measuring contact portion.   3. The temperature sensor according to claim 1, wherein each of the pair of thermocouple wires contacts the contact member at two or more points.   When the length in the axial direction from the distal end of the insulated soot tube to the inner bottom of the outer cylinder is L, and the length in the axial direction from the distal end of the insulated soot tube to the temperature measuring contact portion is M, M The temperature sensor according to any one of claims 1 to 3, wherein L is equal to or greater than L / 2. The temperature sensor according to any one of claims 1 to 4 , wherein the temperature measuring contact portion and the outer cylinder are separated from each other by a diameter of the thermocouple element.

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