WO2019163775A1 - Gas sensor and method for manufacturing gas sensor - Google Patents

Abstract

[Problem] To provide: a gas sensor in which a wiring board and a casing are stacked and which is capable of suppressing the formation of a gap between the casing and the wiring board; and a method for manufacturing a gas sensor. [Solution] An aspect of the present invention provides a gas sensor provided with: a wiring board; a sensor element; a first packing; a first casing body; a plurality of bolts; and a plurality of nuts. This gas sensor has a structure in which respective members of the first casing body, the first packing, and the wiring board are pressed in a stacking direction by the elastic force of a first spring washer, and is configured such that the first packing abuts the wiring board even in areas between a plurality of wiring parts. Accordingly, this gas sensor can suppress the formation of a gap between the first packing and the wiring board in the areas between the plurality of wiring parts.

Description

Gas sensor and gas sensor manufacturing method Cross-reference of related applications

This international application claims priority based on Japanese Patent Application No. 2018-029031 filed with the Japan Patent Office on February 21, 2018, and is based on Japanese Patent Application No. 2018-029031. The entire contents are incorporated herein by reference.

The present disclosure relates to a gas sensor and a method for manufacturing the gas sensor.

As a gas sensor for detecting a specific component contained in a gas to be measured, there is a gas sensor having a wiring board in which a sensor element is suspended and fixed by wire bonding or the like, and a wiring board and a casing are stacked. As a gas sensor having such a configuration, for example, a gas sensor having a configuration in which a wiring board is accommodated in a casing and a part of the wiring board protrudes outside the casing is known (Patent Document 1).

In this technique, a rectangular hole for projecting a part of the wiring board is provided on the side of the casing, and the gap between the hole and the wiring board can be sealed with a sealing material. Further, by suspending and fixing the sensor element to the wiring board, it is possible to improve the gas detection accuracy and responsiveness by reducing the heat capacity of the sensor element and the surrounding thermal influence.

Japanese Patent Laid-Open No. 9-184817

However, when the wiring part is formed on the surface of the wiring board, unevenness is generated on the surface of the board by the thickness of the wiring part. Therefore, when a part of the wiring board protrudes from the casing, the unevenness of the wiring part There is a possibility that a gap is generated between the wiring board and the casing, and gas in the casing leaks from the gap and affects the measurement by the sensor element.

In addition, even in a configuration in which a part of the wiring board does not protrude outside the casing, if a gap is generated between the wiring board and the casing, gas in the casing may leak from the gap.

Therefore, it is desirable that the present disclosure provide a gas sensor and a gas sensor manufacturing method capable of suppressing a gap from being generated between the casing and the wiring board in a gas sensor having a structure in which the wiring board and the casing are laminated.

One aspect of the present disclosure is a gas sensor including a wiring board, a sensor element, a first packing, a first casing body, a plurality of bolts, and a plurality of nuts. This gas sensor has a configuration in which at least a first casing body, a first packing, and a wiring board are fixed using bolts and nuts.

The wiring board is provided with a plurality of wiring portions on at least a part of the outermost surface. The sensor element has a gas detector that detects a specific component contained in the gas to be measured. The sensor element is disposed on the wiring board and electrically connected to the plurality of wiring portions.

The first packing is made of a fluorine resin. A 1st packing is laminated | stacked on the outermost surface in which the wiring part was provided among the wiring boards. The first packing has an opening having a size that encloses the sensor element. The first packing is annular.

The first casing body is laminated on the side opposite to the wiring board in the first packing, and at least a first flow part for flowing the gas to be measured is formed. The first casing body is made of metal or ceramic.

Each of the plurality of bolts is provided so as to penetrate each member of the laminated body in which at least the first casing body, the first packing, and the wiring board are laminated in the laminating direction. The plurality of nuts are tightened against each of the plurality of bolts.

The bolt has a bolt head and a shaft. The bolt head is located outside one side of the stack in the stacking direction. The shaft portion projects from the bolt head toward the other side in the stacking direction of the laminate, and has an outer diameter smaller than that of the bolt head. The shaft portion is coupled with a nut disposed outside the laminated body on the tip side of the shaft portion.

The gas sensor further includes a spring washer. The spring washer is interposed between at least one of the bolt head and the laminated body or between the nut and the laminated body.

The first packing is provided in a state in which the first packing is in contact with the wiring board even in a region between the plurality of wiring parts on the surface in contact with the plurality of wiring parts.

This gas sensor has a structure in which each member of the first casing body, the first packing, and the wiring board is pressed in the stacking direction by the elastic force of the spring washer, and the first packing is also formed in a region between the plurality of wiring portions. It is the structure which contacts a wiring board. Thereby, this gas sensor can suppress that a space | gap arises between a 1st packing and a wiring board in the area | region between several wiring parts.

Therefore, according to this gas sensor, in the gas sensor having a configuration in which the wiring board and the first casing body are stacked, between the wiring board and the first casing body (specifically, between the first packing and the wiring board). It becomes difficult to generate a gap, and a decrease in airtightness can be suppressed. In addition, according to this gas sensor, since the first packing constituted by using a fluorine-based resin is used, an adverse gas (which affects gas detection is affected by the first packing) under use conditions in which the first casing body is at a high temperature. The gas detection accuracy can be satisfactorily obtained in combination with the effect of suppressing the decrease in airtightness.

Next, in the gas sensor described above, the wiring board may include a plurality of lead pins protruding outward from the outermost surface different from the outermost surface on which the plurality of wiring portions are provided. The plurality of lead pins are electrically connected to the plurality of wiring portions inside the wiring board.

This gas sensor can be connected to external equipment via multiple lead pins. For example, a plurality of lead pins may be electrically connected to the circuit board when the gas sensors are stacked on the circuit board. In this case, since the first packing is in contact with the wiring board even in the region between the plurality of wiring portions, it is possible to suppress the occurrence of a gap between the first packing and the wiring board.

Next, in the gas sensor described above, the spring washer includes a first spring washer provided between the bolt head and the laminated body, and a second spring washer provided between the nut and the laminated body. Also good.

In this gas sensor, the spring washer is provided at two locations with respect to one bolt, so that the laminated body (first casing body) is obtained by the elastic force of the two spring washers (first spring washer and second spring washer). The first packing and the wiring board are pressed in the stacking direction. This gas sensor can be configured such that the first packing contacts the wiring board even in a region between the plurality of wiring portions. Thereby, it can suppress that a clearance gap produces between the 1st packing and a wiring board in the field between a plurality of wiring parts.

Next, in the gas sensor described above, the laminate may include a second packing and a second casing body. The second packing is configured using a fluorine-based resin, and is disposed on the opposite side of the wiring substrate from the first packing. A 2nd casing body is laminated | stacked on the opposite side to a wiring board among 2nd packing. The second casing body has at least a second circulation part for circulating the gas to be measured. The second casing body is made of metal or ceramic.

The wiring board is provided with a plurality of wiring portions on each of the first outermost surface of the outermost surface on which the first packing is laminated and the second outermost surface of the outermost surface on which the second packing is laminated. The second packing is provided in a state where the second packing is in contact with the wiring board even in a region between the plurality of wiring parts on the surface in contact with the plurality of wiring parts.

This gas sensor has a structure in which each member of the laminated body (first casing body, first packing, wiring board, second packing, second casing body) is pressed in the laminating direction by the elastic force of the spring washer. The first packing and the second packing are in contact with the wiring board in the region between the wiring portions. Thereby, it can suppress that a clearance gap produces between a 1st packing and a wiring board in a field between a plurality of wiring parts, and a gap arises between a 2nd packing and a wiring board.

Therefore, according to this gas sensor, in the gas sensor having a configuration in which the first casing body, the second casing body, and the wiring board are stacked, there is a gap between the first packing and the wiring board and between the second packing and the wiring board. Is less likely to occur, and deterioration of airtightness can be suppressed. Further, according to this gas sensor, since the first and second packings formed using the fluorine-based resin are used, the first and second packings are used under the use conditions in which the first and second casing bodies are at a high temperature. Thus, the release of gas that affects the gas detection of the gas sensor is suppressed, and in combination with the effect of suppressing the decrease in airtightness, the accuracy of gas detection can be obtained satisfactorily.

Another aspect of the present disclosure is a method for manufacturing a gas sensor, which includes a stacked body forming step, a first fastening step, a heat application step, and a second fastening step.

The gas sensor includes a wiring board, a sensor element, a first packing, a first casing body, a plurality of bolts, and a plurality of nuts. In the gas sensor, at least the first casing body, the first packing, and the wiring board are fixed using bolts and nuts.

The wiring board is provided with a plurality of wiring portions on at least a part of the outermost surface. The sensor element has a gas detector that detects a specific component contained in the gas to be measured. The sensor element is disposed on the wiring board and electrically connected to the plurality of wiring portions.

The first packing is a member configured using a fluorine-based resin. A 1st packing is laminated | stacked on the outermost surface in which the wiring part was provided among the wiring boards. The first packing has an opening having a size that encloses the sensor element. The first packing is annular.

The first casing body is laminated on the side opposite to the wiring board in the first packing, and at least a first flow part for flowing the gas to be measured is formed. The first casing body is made of metal or ceramic.

Each of the plurality of bolts is provided so as to penetrate each member of the laminate in which at least the first casing body, the first packing, and the wiring substrate are laminated in the lamination direction. The plurality of nuts are tightened against each of the plurality of bolts. The bolt includes a bolt head portion and a shaft portion. The bolt head is located outside one side of the stack in the stacking direction. The shaft portion protrudes from the bolt head toward the other side in the stacking direction of the stacked body and has an outer diameter smaller than that of the bolt head. The shaft portion is coupled with a nut disposed outside the laminated body on the tip side of the shaft portion.

The gas sensor further includes a spring washer interposed between at least one of the bolt head and the laminated body or between the nut and the laminated body.

In the laminated body forming step, each member of the first casing body, the first packing, and the wiring board is laminated to form a laminated body. In the first tightening step, a spring washer is interposed between at least one of the bolt head and the laminated body or between the nut and the laminated body, and the bolt shaft portion is attached to each member of the laminated body. And tighten the nut on the tip side of the shaft to temporarily fix each member.

In the heat application step, heat is applied to the first packing after the first tightening step to such an extent that the first packing is softened. In the second tightening step, after the heat application step, the nut fastened to the shaft portion of the bolt is tightened again to fix each member and hold the sensor element inside the laminate.

In this gas sensor manufacturing method, the tightening process is performed twice, not the manufacturing method in which the tightening process is performed only once. Moreover, the adhesiveness of a 1st packing and a wiring board can be improved by giving the heat | fever that a 1st packing softens between a 1st clamping process and a 2nd clamping process (heat provision process).

Further, in this gas sensor manufacturing method, a spring washer is interposed in the first tightening step. For this reason, the gas sensor manufactured by this manufacturing method is a structure which presses each member of a 1st casing body, a 1st packing, and a wiring board in the lamination direction with the elastic force of a spring washer. This gas sensor can be configured such that the first packing contacts the wiring board even in a region between the plurality of wiring portions. Thereby, it can suppress that a clearance gap produces between the 1st packing and a wiring board in the field between a plurality of wiring parts.

Therefore, according to this manufacturing method, in manufacturing a gas sensor having a configuration in which the wiring board and the first casing body are laminated, the gap between the wiring board and the first casing body (specifically, the first packing and the wiring board) A gas sensor in which a gap is difficult to occur can be manufactured, and a decrease in hermeticity in the gas sensor can be suppressed. In addition, since the gas sensor obtained by this manufacturing method uses the first packing made of a fluorine-based resin, the gas sensor can detect the gas from the first packing under use conditions in which the first casing body is at a high temperature. The release of the influential gas is suppressed, and the accuracy of gas detection can be obtained well in combination with the effect of suppressing the decrease in airtightness.

It is sectional drawing showing the internal structure of a gas sensor. It is a disassembled perspective view of a gas sensor. It is a perspective view of a detection part. It is a disassembled perspective view of a detection part. It is a disassembled perspective view of a conversion part. It is sectional drawing showing the laminated structure of the part by which a some wiring part, a volt | bolt, and a nut are arrange | positioned among detection parts. It is a flowchart showing each process (laminated body formation process, 1st clamping process, heat provision process, 2nd clamping process) at the time of manufacturing a detection part. It is explanatory drawing showing the expanded cross section of the 1st board part in each of a laminated body formation process and a 2nd clamping process, a sealing material, a ceramic wiring board, and a wiring part. It is explanatory drawing showing the measurement result of the leak amount with respect to the frequency | count of a thermal cycle about each of three types of fastening states. It is a disassembled perspective view of a 2nd detection part. It is a perspective view of a ceramic wiring board. It is sectional drawing showing the laminated structure of the part by which a some wiring part, a volt | bolt, and a nut are arrange | positioned among 2nd detection parts. It is explanatory drawing showing the expanded cross section of the casing body in each of a laminated body formation process and a 2nd clamping process, a sealing material, a ceramic wiring board, and a wiring part regarding a 2nd detection part.

DESCRIPTION OF SYMBOLS 1 ... Gas sensor (exhalation sensor), 10 ... Detection part, 10a ... Bolt, 10a1 ... Bolt head, 10a2 ... Shaft part, 10b ... Nut, 10c ... 1st spring washer, 10d ... 2nd spring washer, 11 ... 1st Plate part, 12 ... 2nd plate part, 13 ... Sealing material (gasket), 14 ... Sealing material (gasket), 15 ... Ceramic wiring board, 15d ... Wiring part, 15e ... Base end part, 15h ... Opening part, 15p ... Conductive pad section, 19 ... cassette connector, 20 ... element section, 21 ... substrate, 22 ... first heater, 23 ... sensing element, 30 ... conversion section, 51 ... second heater, 60 ... gas flow pipe, 110 ... second Detecting part, 111 ... casing body, 113 ... sealing material (gasket), 115 ... ceramic wiring board, 115d ... wiring part, 115p ... conductive pad part, 120 ... second element part, ... breath (the gas to be measured).

Hereinafter, embodiments to which the present disclosure is applied will be described with reference to the drawings.

In addition, this indication is not limited to the following embodiment at all, and it cannot be overemphasized that various forms may be taken as long as it belongs to the technical scope of this indication.

[1. First Embodiment]
[1-1. overall structure]
As a first embodiment, a gas sensor 1 (exhalation sensor 1) will be described.

The gas sensor 1 is used, for example, for the purpose of measuring an extremely low concentration (several ppb to several hundred ppb level) of NO in the breath G (measured gas G) for asthma diagnosis.

As shown in FIGS. 1 and 2, the gas sensor 1 includes a main body 90, a detection unit 10, a conversion unit 30, and a gas circulation pipe 60.

The main body 90 is provided as a box-shaped housing. The main body 90 is configured using a resin material. The main body 90 accommodates the detection unit 10, the conversion unit 30, and the gas flow pipe 60 therein.

The main body 90 includes a first member 91 and a second member 92, as shown in FIG. The first member 91 and the second member 92 are integrally assembled with a screw 93 to form the main body 90.

The main body 90 includes a detection unit space 90a, a conversion unit space 90b, and a distribution pipe space 90c. The detection unit space 90a is a space in which the detection unit 10 is arranged. The conversion unit space 90b is a space in which the conversion unit 30 is arranged. The flow pipe space 90c is a space in which the gas flow pipe 60 is disposed.

The detection unit 10 is connected to a cylindrical cassette connector 19. The cassette connector 19 is configured to be connectable to an external device (not shown) via a lead wire 19a and a connection connector 19b. A detection signal output from the detection unit 10 is output from the cassette connector 19 to an external device via the lead wire 19a and the connection connector 19b. The detection unit 10 includes a detection heater (not shown) that generates heat when energized. Heater power to the detection heater is supplied from an external device to the detection heater via the connection connector 19b, the lead wire 19a, and the cassette connector 19.

The conversion unit 30 is connected to a cylindrical cassette connector 39. The cassette connector 39 is configured to be connectable to an external device (not shown) via a lead wire 39a and a connection connector 39b. As will be described later, the conversion unit 30 includes a second heater 51 (see FIG. 5) that generates heat when energized. Heater power to the second heater 51 is supplied from the external device to the second heater 51 via the connection connector 39b, the lead wire 39a, and the cassette connector 39.

The detection unit 10 includes an introduction pipe 12a for introducing the exhaled breath G after conversion, and a discharge pipe 11a for discharging the exhaled breath G after detection. The conversion unit 30 includes a pipe 31a (also referred to as an introduction pipe 31a) for introducing exhalation G, and a pipe 32b (also referred to as an exhaust pipe 32b) for discharging the exhaled breath G after conversion. The introduction pipe 31a and the discharge pipe 32b are each made of a metal material (for example, stainless steel).

As shown in FIG. 2, exhaled gas G is introduced into the conversion unit 30 through the sub-pipes 85, 84, and 83, exits the conversion unit 30, and then is introduced into the detection unit 10 through the gas distribution pipe 60. The After the specific component in the exhalation G is detected by the detection unit 10, the exhalation G is discharged to the outside through the auxiliary pipe 81 connected to the detection unit 10.

The gas distribution pipe 60 is a tube made entirely of a polymer material (fluorine rubber, fluoroelastomer, etc.) containing fluorine. An inlet end 60 a of the gas flow pipe 60 is connected to the discharge pipe 32 b of the conversion unit 30, and an outlet end 60 b of the gas flow pipe 60 is connected to the introduction pipe 12 a of the detection unit 10. That is, the gas flow pipe 60 constitutes a gas flow path for the exhalation G between the conversion unit 30 and the detection unit 10.

1 and 2, the gas sensor 1 includes a first heat insulating material 71, a second heat insulating material 72, and a third heat insulating material 73 inside the main body 90. The 1st heat insulating material 71, the 2nd heat insulating material 72, and the 3rd heat insulating material 73 are comprised, for example using glass fiber.

The 1st heat insulating material 71 and the 2nd heat insulating material 72 are arrange | positioned in the space 90b for conversion parts. The 1st heat insulating material 71 is a shape arrange | positioned at the upper side of the conversion part 30, a horizontal side, and the lower side, and is provided in order to insulate the conversion part 30 and the main-body part 90. FIG. The second heat insulating material 72 has a plate shape and is disposed below the first heat insulating material 71. The 3rd heat insulating material 73 is arrange | positioned in the space 90a for detection parts. The 3rd heat insulating material 73 is plate shape, is arrange | positioned under the detection part 10, and is equipped in order to insulate the detection part 10 and the space 90b for conversion parts.

[1-2. Detection unit]
As shown in FIGS. 3 and 4, the detection unit 10 includes a first plate portion 11, a sealing material 13 (gasket 13), a ceramic wiring substrate 15, a sealing material 14 (gasket 14), and a second plate portion. 12 are laminated in this order.

The first plate part 11 is made of a metal material (for example, stainless steel) and includes a discharge pipe 11a for discharging the exhalation G. The 2nd board part 12 is formed with the metal material (for example, stainless steel), and is provided with the inlet tube 12a for introducing the exhalation G. Each of the sealing materials 13 and 14 has a rectangular frame shape, and is configured using a fluorine-based resin (for example, fluorine rubber, fluorinated hydrocarbon polymer, or the like). The ceramic wiring board 15 includes an opening 15h formed at the center of the rectangular plate shape and a narrow base end portion 15e protruding from one side of the rectangular plate shape.

The detection unit 10 includes an element unit 20 and current-carrying members 16 and 17. The element unit 20 is disposed inside the opening 15 h of the ceramic wiring substrate 15. The energizing members 16 and 17 are members formed of a conductive material, and the element unit 20 is suspended and fixed in the opening 15h.

The first plate portion 11, the sealing material 13, the ceramic wiring substrate 15, the sealing material 14, and the second plate portion 12 are laminated in this order, and are fastened and fixed using bolts 10 a and nuts 10 b, The sealing members 13 and 14 are pressed between the second plate portion 12 and the ceramic wiring substrate 15 is sealed. The sealing materials 13 and 14 include openings 13a and 14a each having a size that encloses the element portion 20, respectively.

The bolt 10a includes a bolt head portion 10a1 and a shaft portion 10a2. The bolt head portion 10 a 1 is disposed outside the first plate portion 11. The shaft portion 10a2 has a smaller outer diameter than the bolt head portion 10a1, and is configured in such a manner that the nut 10b is coupled. The shaft portion 10a2 protrudes from the bolt head portion 10a1 toward the second plate portion 12. A nut 10b disposed outside the second plate portion 12 is coupled to the distal end side of the shaft portion 10a2.

The first spring washer 10c is inserted between the bolt head portion 10a1 and the first plate portion 11 in the shaft portion 10a2. A second spring washer 10d is inserted between the nut 10b and the second plate portion 12 in the shaft portion 10a2.

As shown in FIG. 6, in the detection unit 10, the elastically deformed sealing materials 13 and 14 are in contact with each other between the plurality of wiring units 15 d on the surface of the ceramic wiring substrate 15 without any gap. As a result, the detection unit 10 has a structure in which the space between the first plate portion 11 and the ceramic wiring substrate 15 and the space between the second plate portion 12 and the ceramic wiring substrate 15 are sealed (sealed). Gas leakage between 15h and the outside can be suppressed.

The detection unit 10 is configured to introduce the exhalation G from the introduction tube 12a, and after the exhalation G contacts the element unit 20 to detect the concentration of a specific component, the exhalation G is discharged from the discharge tube 11a to the outside.

The element unit 20 includes a rectangular plate-shaped substrate 21, a first heater 22 disposed on the upper surface (surface facing upward in FIG. 4) side of the substrate 21, and a detection element 23 disposed on the lower surface side of the substrate 21. ,have. The element unit 20 has an integrated structure in which the detection element 23 and the first heater 22 are stacked on the top and bottom of the substrate 21.

The sensing element 23 comes into contact with the exhalation G that has passed through the conversion unit 30 and changes in electrical characteristics according to the concentration of NO _{2 in} the exhalation G. The 1st heater 22 heats detection element 23 to the 1st temperature which is operating temperature by generating heat by energization. The output terminal of the detection element 23 and the energization terminal of the first heater 22 are electrically connected to the lead portion of the ceramic wiring substrate 15 via the energization members 16 and 17. In addition, the temperature sensor for measuring the temperature of the 1st heater 22 is arrange | positioned on the surface where the 1st heater 22 is arrange | positioned among the board | substrates 21 with the form which has a predetermined pattern.

The substrate 21 can be a ceramic substrate, for example. The sensing element 23 can be formed, for example, as a mixed potential sensor (nitrogen oxide sensor) using a solid electrolyte body and a pair of electrodes made of different materials disposed on the surface of the solid electrolyte body. The first heater 22 can be formed as a meandering pattern. In addition, as the detection element 23, you may apply the resistance change type sensor provided with a metal oxide semiconductor and a pair of electrode.

A plurality of conductive pad portions 15p are arranged on the front and back surfaces of the base end portion 15e of the ceramic wiring substrate 15. The plurality of conductive pad portions 15p are electrically connected to the detection element 23 and the first heater 22 via the lead portions and the energization members 16 and 17, respectively. The conductive pad portion 15p on the back side of the ceramic wiring board 15 is not shown.

The electrical signal output from the detection element 23 is output to the cassette connector 19 via the conductive pad portion formed on the back surface side of the ceramic wiring substrate 15, and is output to the external device via the cassette connector 19. The electric power supplied from the external device is supplied to the conductive pad portion 15p formed on the surface side of the ceramic wiring substrate 15 via the cassette connector 19, and is supplied to the first heater 22 via the conductive pad portion 15p. . Thereby, electricity supply to the 1st heater 22 is performed and the 1st heater 22 generates heat.

[1-3. Conversion unit]
As shown in FIG. 5, the conversion unit 30 includes a rectangular plate-shaped upper lid 31, a rectangular frame-shaped spacer 33 a 1, a rectangular plate-shaped upper catalyst support unit 35 a 1 in which the catalyst 41 is applied and formed on both surfaces thereof, A spacer 33a2, a rectangular plate-shaped upper catalyst support portion 35b1 on which the catalyst 42 is applied and formed on one surface (the surface facing the upper side in the figure), and a narrow base end portion 50e protrudes from one side of the rectangular plate shape. The heater substrate 50, the lower catalyst support part 35b2 having a rectangular plate shape on which the catalyst 42 is applied and formed on one side (the side facing the lower side in the figure), the spacer 33a3, and the catalyst 41 are applied and formed on both sides. The rectangular plate-shaped lower catalyst support portion 35a2, the spacer 33a4, and the rectangular plate-shaped lower lid 32 are laminated in this order.

The spacers 33a1 to 33a4 have the same shape and are collectively referred to as the spacer 33a. The upper catalyst support part 35a1 and the lower catalyst support part 35a2 have the same shape, and are collectively referred to as the catalyst support part 35a. The upper catalyst support portion 35b1 and the lower catalyst support portion 35b2 have the same shape, and are collectively referred to as the catalyst support portion 35b.

Each member 31, 32, 33 a, 35 a, 35 b, 50 is made of, for example, ceramic, and the members are laminated in an airtight manner via, for example, a glass or inorganic adhesive layer. ing.

The upper lid 31 is configured by attaching a pipe 31a (introduction pipe 31a) extending along the through hole to a through hole (not shown) provided in a part of the rectangular plate. The pipe 31 a rises to the outside from the through hole, then bends 90 degrees along the plate surface of the upper lid 31, and one bent end extends toward the base end portion 50 e of the heater substrate 50.

The lower lid 32 includes a through hole 32a provided in a part of the rectangular plate, and a pipe 32b (discharge pipe 32b) extending from the through hole 32a. The pipe 32 b rises outside from the through hole 32 a, and then bends 90 degrees along the plate surface of the lower lid 32, and one bent end extends in a direction opposite to the base end portion 50 e of the heater substrate 50. .

In the present embodiment, the pipe 31a attached to the upper lid 31 forms an exhalation G introduction pipe, and the pipe 32b forms an exhaust pipe.

On both surfaces of the upper catalyst support portion 35a1, the catalyst 41 is applied and formed in a substantially rectangular shape at a position corresponding to the inside of the internal space of the spacers 33a1 and 33a2. The upper catalyst support portion 35a1 has a slit-shaped opening 35s in a region adjacent to one side of the catalyst 41. The exhaled gas G introduced from the pipe 31a contacts the upper catalyst 41 in the inner space of the spacer 33a1, and then contacts the lower catalyst 41 in the inner space of the spacer 33a2 through the opening 35s.

The catalyst 42 is applied and formed in a substantially rectangular shape on one side of the upper catalyst support 35b1 (the surface facing the upper side in the figure) at a position corresponding to the inside of the internal space of the spacer 33a2. The upper catalyst support portion 35b1 has a round hole-shaped opening 35h at the center of one side of the catalyst 42 (obliquely upper right side in the figure). The exhaled gas G contacts the catalyst 42 in the internal space of the spacer 33a2, and then flows downward through the opening 35h.

The opposite surface of the upper catalyst support portion 35b1 is in contact with the heater substrate 50. As the second heater 51 having a meandering pattern formed on the surface of the heater substrate 50 generates heat, the upper catalyst support portion 35b1 and the catalyst 42 are brought to a second temperature different from the first temperature via the heater substrate 50. Heated. On the back surface of the heater substrate 50, a temperature sensor (not shown) for detecting the heating temperature of the second heater 51 is arranged in a form having a predetermined pattern. The heater substrate 50 includes a round hole-shaped opening 50 h that overlaps the opening 35 h. The exhalation G that has passed through the opening 35h flows downward through the opening 50h.

As the catalyst 42 is heated, the exhalation G in the internal space of the spacer 33a2 facing the catalyst 42, and thus the catalyst 41 facing the spacer 33a2 is also heated. The heat of the catalyst 41 is also transmitted from the upper catalyst support portion 35a1 to the catalyst 41 on the opposite surface (upper surface).

As the catalysts 41 and 42, a known catalyst material that converts the first gas component contained in the expiration gas G into the second gas component, for example, converts NO in the expiration gas G into NO ₂ can be used. The catalysts 41 and 42 adjust the partial pressure ratio between NO and NO ₂ in the exhalation G.

A plurality of conductive pad portions 50p are disposed on the surface of the base end portion 50e of the heater substrate 50, respectively. The plurality of conductive pad portions 50p are electrically connected to the second heater 51 and a temperature sensor (not shown) through lead portions, respectively.

The electric power supplied from the external device is supplied to the conductive pad portion 50p formed on the surface side of the heater substrate 50 through the cassette connector 39, and is supplied to the second heater 51 through the conductive pad portion 50p. Thereby, electricity supply to the 2nd heater 51 is performed and the 2nd heater 51 generates heat.

The lower catalyst support portion 35b2 is in contact with the lower surface (the surface facing the lower side of the drawing) of the heater substrate 50, and the upper catalyst support portion 35b1 is connected to the lower surface (the surface facing the lower side of the drawing) of the lower catalyst support portion 35b2. Similarly to the above, the catalyst 42 is applied and formed in a substantially rectangular shape.

The lower catalyst support 35b2 on the lower side of the heater substrate 50, the spacer 33a3, the lower catalyst support 35a2, the spacer 33a4, and the lower lid 32 are arranged on the upper catalyst support 35b1 on the upper side of the heater substrate 50 via the heater substrate 50. The spacer 33a2, the upper catalyst support 35a1, the spacer 33a1, and the upper lid 31 are arranged symmetrically and perform substantially the same function, and thus detailed description thereof is omitted.

The exhaled gas G flowing downward through the opening 50h and the opening 35h of the lower catalyst support 35b2 comes into contact with the catalyst 42 in the internal space of the spacer 33a3, and then the upper catalyst 41 in the lower catalyst support 35a2. Contact with. Thereafter, the expiratory gas G contacts the lower catalyst 41 in the lower catalyst support portion 35a2 in the inner space of the spacer 33a4 through the opening 35s, and is discharged from the pipe 32b.

As described above, the expiratory gas G contacts the catalyst heated to the second temperature, and the first gas component (specifically NO) contained in the expiratory gas G is the second gas component (specifically NO ₂ ). Is converted to

[1-4. Manufacturing method of gas sensor]
Of the manufacturing method of the gas sensor 1, first, a manufacturing method of the detection unit 10 will be described.

When manufacturing the detection part 10, each process (laminated body formation process, 1st clamping process, heat provision process, 2nd clamping process) shown in FIG. 7 is implemented.

In the manufacturing method of the detection unit 10, first, in S110, a laminated body forming step is executed. In the laminated body forming step, the first plate portion 11, the sealing material 13, the ceramic wiring substrate 15, the sealing material 14, and the second plate portion 12 are laminated in this order to form a laminated body. At this time, as the ceramic wiring board 15, the one in which the element portion 20 is assembled in advance is used.

At this time, as shown in the upper side of FIG. 8, the surfaces of the sealing material 13 and the ceramic wiring board 15 are separated from each other by the wiring portion 15d.

In the next S120, the first tightening process is executed. In the first tightening step, first, the first spring washer 10c is interposed between the bolt head portion 10a1 and the first plate portion 11, and the second spring washer 10d is interposed between the nut 10b and the second plate portion 12. So that the shaft portion 10a2 of the bolt 10a penetrates each member of the laminated body.

Furthermore, in the first tightening step, each member of the laminate is temporarily fixed by tightening the nut 10b on the tip side of the shaft portion 10a2. At this time, the nut 10b is tightened with a tightening strength at which the sealing material 13 and the sealing material 14 are elastically deformed.

In the next S130, a heat application step is executed. In the heat application step, the laminated body is heated using the first heater 22 at 395 ° C. for 20 minutes. That is, the laminated body is heated using the first heater 22 so that the sealing material 13 and the sealing material 14 are heated to such a degree that the sealing material 13 and the sealing material 14 are softened.

In the next S140, the second tightening process is executed. In the second tightening step, the nut 10b is tightened to fix each member of the laminate, and the element unit 20 is held inside the laminate. At this time, by tightening the nut 10b with a tightening strength at which the sealing material 13 and the sealing material 14 are elastically deformed, the sealing material 13 and the ceramic wiring board 15 abut on each other in a region between the plurality of wiring portions 15d. At the same time, the sealing material 14 and the ceramic wiring board 15 are in contact with each other without any gap. That is, the sealing material 13 (sealing material 14) is elastically deformed through the first tightening step, the heat application step, and the second tightening step, and thereby along the surface of the wiring portion 15d as shown in the lower side of FIG. And a state in contact with the surface of the ceramic wiring board 15.

In addition, description is abbreviate | omitted about the manufacturing method of components other than the detection part 10 (conversion part 30 etc.).

In the manufacturing method of the gas sensor 1, after each component (sub piping 85, 84, 83, cassette connector 19, detection unit 10, sub piping 81, cassette connector 39, conversion unit 30, gas distribution pipe 60, etc.) is manufactured. , Each component is connected to each other. Next, in the method for manufacturing the gas sensor 1, the first member 91 and the second member 92 are fixed with the screws 93 while the components connected to each other are accommodated in the first member 91 and the second member 92. Thus, the manufacturing process of the gas sensor 1 is completed.

[1-5. Measurement result]
Here, the measurement result measured about the gas leak of a detection part is demonstrated.

In this measurement, it was measured whether or not a difference in the gas leakage state of the detection unit 10 occurred due to the difference in the fastening state using the bolt 10a, the nut 10b, the first spring washer 10c, and the second spring washer 10d.

Specifically, three types of fastening states are measured: “(a) with washer, with additional tightening”, “(b) without washer, with additional tightening”, and “(c) with washer, without additional tightening”. Carried out. “Washer present / absent” represents the case where the first spring washer 10c and the second spring washer 10d are used and the case where they are not used. “With / without additional tightening” represents when the second tightening process is performed and when it is not performed.

The measurement is performed by performing a cooling cycle in which the high temperature environment (395 ° C.) by energization ON (heating) to the first heater 22 and the cooling by energization OFF to the first heater 22 are alternately repeated. The amount of gas leakage (leakage amount) from the inside (opening 15h) was measured. At this time, the high temperature environment and the cooling processing time were set to energization ON 20 minutes and energization OFF 10 minutes, respectively.

The measurement results of the leak amount with respect to the number of cooling cycles for each of the three types of fastening states are shown in FIG.

As shown in FIG. 9, the leak amount at the maximum number of cooling cycles (43 times) is the smallest in “(a) with washer, with additional tightening”, followed by “(b) without washer, with additional tightening”. “(C) with washer, no additional tightening” is the most common.

In addition, the amount of increase in the leak amount with respect to the increase in the number of cooling cycles is “(a) with washer, with additional tightening” is smaller than “(b) without washer, with additional tightening”. “(C) Washer present, no additional tightening” indicates that the amount of leakage is reduced when the number of cooling cycles is 43 compared to 28, but “(a) With washer, additional tightening”. Since the absolute value of the leak amount is larger than “Yes”, it cannot be evaluated that the airtightness is high.

According to this measurement result, “(a) with washer, with additional tightening” as an example of the present disclosure is “(b) without washer, with additional tightening” and “(c) with a washer” as comparative examples. It can be seen that the airtightness is higher than “no retightening”.

[1-6. effect]
As described above, in the manufacturing method of the gas sensor 1 of the present embodiment, the manufacturing process of the detection unit 10 is not a manufacturing method in which the tightening process is performed only once, but the tightening process (first tightening process: S120) twice. The second tightening step: S140) is performed.

Further, by applying heat to such an extent that the sealing material 13 and the sealing material 14 are softened between the first fastening process and the second fastening process (heat application process: S130), the sealing material 13 and the ceramic wiring board 15 And the adhesion between the sealing material 14 and the ceramic wiring board 15 can be improved.

In the manufacturing method of the present embodiment, the first spring washer 10c and the second spring washer 10d are interposed in the first tightening step (S120). For this reason, the gas sensor 1 (specifically, the detection unit 10) manufactured by this manufacturing method has the first plate portion 11, the sealing material 13, and the ceramic by the elastic force of the first spring washer 10c and the second spring washer 10d. In this structure, each member of the wiring board 15, the sealing material 14, and the second plate portion 12 is pressed in the stacking direction. The gas sensor 1 can be configured such that the sealing material 13 and the sealing material 14 are in contact with the ceramic wiring board 15 even in a region between the plurality of wiring portions 15d. As a result, a gap is generated between the sealing material 13 and the ceramic wiring board 15 in a region between the plurality of wiring portions 15d, and a gap is generated between the sealing material 14 and the ceramic wiring board 15. Can be suppressed. This can be understood from the above measurement results (see FIG. 9).

Therefore, according to the manufacturing method (gas sensor manufacturing method) of the present embodiment, in manufacturing the gas sensor 1 having a configuration in which a part of the ceramic wiring board 15 protrudes outside the first plate portion 11 and the second plate portion 12. In addition, it is possible to manufacture the gas sensor 1 in which a gap is hardly generated between the sealing material 13 and the ceramic wiring board 15 and between the sealing material 14 and the ceramic wiring board 15, and it is possible to suppress a decrease in hermeticity in the gas sensor 1.

[1-7. Correspondence of wording]
Here, the correspondence between words will be described.

The gas sensor 1 or the detection unit 10 corresponds to an example of a gas sensor, the ceramic wiring board 15 corresponds to an example of a wiring board, the wiring part 15d corresponds to an example of a wiring part, and the element part 20 corresponds to an example of a sensor element. The detection element 23 corresponds to an example of a gas detection unit. The sealing material 13 corresponds to an example of a first packing, the sealing material 14 corresponds to an example of a second packing, the first plate portion 11 corresponds to an example of a first casing body, and the discharge pipe 11a corresponds to a first flow portion. The second plate portion 12 corresponds to an example of a second casing body, and the introduction pipe 12a corresponds to an example of a second circulation portion.

The bolt 10a corresponds to an example of a bolt, the nut 10b corresponds to an example of a nut, the bolt head 10a1 corresponds to an example of a bolt head, the shaft portion 10a2 corresponds to an example of a shaft portion, and the first spring washer 10c corresponds to an example of a first spring washer, and the second spring washer 10d corresponds to an example of a second spring washer.

S110 corresponds to an example of a laminate forming process, S120 corresponds to an example of a first fastening process, S130 corresponds to an example of a heat application process, and S140 corresponds to an example of a second fastening process.

[2. Second Embodiment]
[2-1. overall structure]
Next, a second gas sensor (second breath sensor) including the second detection unit 110 will be described as a second embodiment.

The second gas sensor is similar to the gas sensor 1 of the first embodiment. For example, for the diagnosis of asthma, the second gas sensor has a very low concentration (several ppb to several hundreds ppb level) of NO in the expiratory gas G (measurement gas G). Used for measuring

The second gas sensor has a configuration in which a part of the gas sensor 1 is changed, and at least the detection unit 10 in the gas sensor 1 is replaced with the second detection unit 110. The second gas sensor will be described with a focus on portions different from the gas sensor 1.

The second gas sensor includes a second main body part, a second detection part 110, a conversion part 30, and a gas flow pipe 60.

Although the illustration is omitted, the second main body portion is provided as a box-shaped housing in the same manner as the main body portion 90. The second main body is configured using a resin material. The 2nd main part stores the 2nd detection part 110, conversion part 30, and gas distribution pipe 60 inside. The second main body includes a detection unit space, a conversion unit space, and a distribution pipe space. The space for the detection unit is a space in which the second detection unit 110 is arranged. The conversion unit space is a space in which the conversion unit 30 is arranged. The space for the circulation pipe is a space where the gas circulation pipe 60 is arranged.

In addition, since the conversion part 30 and the gas distribution pipe 60 are the structures similar to 1st Embodiment, description is abbreviate | omitted.

[2-2. Detection unit]
As shown in the exploded perspective view of FIG. 10, the second detection unit 110 is configured by stacking a casing body 111, a seal material 113 (gasket 113), and a ceramic wiring board 115 in this order.

The casing body 111 includes a metal (for example, stainless steel) introduction pipe 111a, a metal (for example, stainless steel) discharge pipe 111b, and a ceramic (for example, alumina) plate portion 111c. The introduction tube 111 a is an introduction unit for introducing the exhalation G after conversion by the conversion unit 30. The discharge pipe 111b is a discharge unit for discharging the exhaled breath G after detection. The introduction pipe 111a and the discharge pipe 111b are fixed to the plate portion 111c by brazing. The plate part 111c is provided with a through hole (not shown) penetrating in the thickness direction of the plate at a fixed position of the introduction tube 111a and the discharge tube 111b.

The sealing material 113 has a rectangular frame shape, and is configured using a fluorine-based resin (for example, fluorine rubber, fluorinated hydrocarbon polymer, or the like).

The ceramic wiring board 115 has a rectangular plate shape, and includes an element arrangement portion 115h formed as a concave space at the center thereof. The ceramic wiring board 115 includes a plurality of wiring portions 115d on at least a part of the outermost surface. The ceramic wiring board 115 includes a plurality of lead pins 115p on the outermost surface different from the outermost surface on which the plurality of wiring portions 115d are provided (specifically, the outermost surface on the side periphery constituting the side periphery). The plurality of lead pins 115p protrude outward from the outermost surface (side outermost surface) of the ceramic wiring board 115. Specifically, the plurality of lead pins 115p having a substantially L-shape project outward from the two outermost outer peripheral surfaces of the rectangular ceramic wiring board 115. The plurality of lead pins 115p are electrically connected to the plurality of wiring portions 115d inside the ceramic wiring substrate 115.

Moreover, the 2nd detection part 110 is provided with the 2nd element part 120 and the several electricity supply member 116, as shown in FIG. The second element unit 120 is arranged on the element arrangement unit 115 h of the ceramic wiring substrate 115. The energizing member 116 is made of a conductive material.

The second element unit 120 includes a rectangular plate-shaped substrate 121, a first heater 122 disposed inside the substrate 121, and a detection element 123 disposed on the outermost surface of the substrate 121. The second element unit 120 has an integral structure in which the detection element 123 and the first heater 122 are disposed on the substrate. The detection element 123 is a gas detection unit that detects a specific component (NO) contained in the gas to be measured (expired gas G). The second element portion 10 is fixed to the element arrangement portion 115h of the ceramic wiring substrate 115 via an adhesive.

The sensing element 123 comes into contact with the exhaled gas G that has passed through the conversion unit 30 and changes its electrical characteristics according to the concentration of NO _{2 in} the exhaled gas G. The first heater 122 generates heat by energization to heat the detection element 123 to the first temperature that is the operating temperature. Note that a temperature sensor for measuring the temperature of the heater is disposed on the substrate 121 in a form having a predetermined pattern.

The substrate 121 can be formed as a ceramic substrate, for example. The sensing element 123 can be formed, for example, as a mixed potential sensor (nitrogen oxide sensor) using a solid electrolyte body and a pair of electrodes made of different materials disposed on the surface of the solid electrolyte body. The first heater 122 can be formed as a meandering pattern. Note that as the detection element 123, a resistance variable sensor including a metal oxide semiconductor and a pair of electrodes may be applied.

The 2nd element part 120 is provided with the some electrode part 120a in the outermost surface, as shown in FIG. A part of the plurality of electrode portions 120a is electrically connected to the output terminal of the detection element, and constitutes a signal output unit that outputs a detection signal from the detection element. The other part of the plurality of electrode parts 120a is electrically connected to the energization terminal of the heater, and constitutes a power receiving part that receives power supplied to the heater.

The second element unit 120 is electrically connected to the plurality of wiring units 115d. Specifically, the plurality of electrode portions 120a are electrically connected to the plurality of wiring portions 115d through the plurality of current-carrying members 116.

The sealing material 113 is laminated on the outermost surface of the ceramic wiring board 115 where the wiring part 115d is provided. The sealing material 113 has an annular shape (rectangular frame shape) in which an opening 113 a having a size that encloses the second element portion 120 is formed.

The casing body 111 is laminated on the opposite side of the sealing material 113 from the ceramic wiring board 115. The casing body 111 has at least an introduction pipe 111a and a discharge pipe 111b for circulating the gas to be measured. The casing body 111 includes at least a metal part or a ceramic part.

The casing body 111, the sealing material 113, and the ceramic wiring board 115 are laminated in this order, and are tightened and fixed using the bolts 10a and the nuts 10b, whereby the sealing material 113 is pressed between the casing body 111 and the ceramic wiring board 115. The Thereby, the space between the casing body 111 and the ceramic wiring board 115 is sealed (sealed) by the sealing material 113.

The first spring washer 10c is inserted between the bolt head 10a1 and the casing body 111 in the shaft portion 10a2 of the bolt 10a. In addition, the spring washer is not provided between the nut 10b and the 2nd board part 12 among the axial parts 10a2 of the volt | bolt 10a.

As shown in FIG. 12, in the second detection unit 110, the elastically deformed seal material 113 is in contact with the gap between the plurality of wiring units 115d on the surface of the ceramic wiring board 115 without any gap. Thereby, the 2nd detection part 110 becomes a structure where between the casing body 111 and the ceramic wiring board 115 is sealed (sealed), and the gas leakage between the element arrangement | positioning part 115h and the exterior can be suppressed.

The second detection unit 110 introduces the exhalation G from the introduction tube 111a, and after the exhalation G contacts the second element unit 120 and detects the concentration of the specific component, the exhalation G is discharged to the outside from the discharge tube 111b. It is.

The plurality of lead pins 115p in the ceramic wiring substrate 115 are electrically connected to the detection element and the heater of the second element unit 120 through the plurality of wiring units 115d and the energization member 116, respectively.

The electrical signal output from the sensing element is output to a circuit board (not shown) via a plurality of lead pins 115p formed on the ceramic wiring board 115, and is output to an external device via the circuit board. The electric power supplied from the external device is supplied to the plurality of lead pins 115p formed on the ceramic wiring substrate 115 through the circuit board, and is supplied to the heater through the plurality of lead pins 115p. Thereby, the heater is energized and the heater generates heat. As described above, the plurality of lead pins 115p configure a signal path of a detection signal output from the second detection unit 110, a power supply path to the second detection unit 110, and the like.

[2-3. Manufacturing method of gas sensor]
Of the methods for manufacturing the second gas sensor, a method for manufacturing the second detector 110 will be briefly described.

When manufacturing the 2nd detection part 110, similarly to the detection part 10 of 1st Embodiment, each process shown in FIG. 7 (a laminated body formation process, a 1st clamping process, a heat provision process, a 2nd clamping process). To implement.

In the manufacturing method of the second detection unit 110, first, in S110, a stacked body forming step is executed. In the laminated body forming step, the casing body 111, the sealing material 113, and the ceramic wiring board 115 are laminated in this order to form a laminated body. At this time, as the ceramic wiring board 115, the one in which the second element unit 120 is assembled in advance is used.

At this time, as shown on the upper side of FIG. 13, the surfaces of the sealing material 113 and the ceramic wiring board 115 are separated from each other by the wiring portion 115d.

In the next S120, the first tightening process is executed. In the first tightening step, first, the shaft portion 10a2 of the bolt 10a is passed through each member of the laminate so that the first spring washer 10c is interposed between the bolt head portion 10a1 and the casing body 111.

Furthermore, in the first tightening step, each member of the laminate is temporarily fixed by tightening the nut 10b on the tip side of the shaft portion 10a2. At this time, the nut 10b is tightened with a tightening strength at which the sealing material 113 is elastically deformed.

In the next S130, a heat application step is executed. In the heat application step, the laminate is heated at 395 ° C. for 20 minutes using the heater of the second element unit 120. That is, the stacked body is heated using the heater of the second element portion 120 so that the sealing material 113 is heated to such an extent that the sealing material 113 is softened.

In the next S140, the second tightening process is executed. In the second tightening step, each member of the multilayer body is fixed by tightening the nut 10b, and the second element portion 120 is held inside the multilayer body. At this time, by tightening the nut 10b with a tightening strength at which the sealing material 113 is elastically deformed, the sealing material 113 and the ceramic wiring board 115 abut on each other in a region between the plurality of wiring portions 115d. That is, the seal material 113 is elastically deformed through the first tightening step, the heat application step, and the second tightening step, thereby forming a shape along the surface of the wiring portion 115d as shown in the lower side of FIG. Then, it comes into contact with the surface of the ceramic wiring board 115. In particular, the sealing material 113 is provided in a state in contact with the surface of the ceramic wiring board 115 even in a region between the plurality of wiring portions 115 d.

In addition, description is abbreviate | omitted about the manufacturing method of components other than the 2nd detection part 110 (conversion part 30 etc.).

In the manufacturing method of the second gas sensor, each component (sub piping 85, 84, 83, circuit board, second detection unit 110, sub piping 81, cassette connector 39, conversion unit 30, gas distribution pipe 60, etc.) is manufactured. After that, each component is connected to each other. Next, in the method for manufacturing the second gas sensor, the components connected to each other are accommodated in the second main body, thereby completing the manufacturing process of the second gas sensor.

[2-4. effect]
As described above, in the manufacturing method of the second gas sensor of the second embodiment, the manufacturing process of the second detection unit 110 is not a manufacturing method in which the tightening process is performed only once, but the tightening process (first process). First tightening step: S120, second tightening step: S140).

Further, by applying heat to such an extent that the sealing material 113 is softened between the first fastening process and the second fastening process (heat application process: S130), the adhesion between the sealing material 113 and the ceramic wiring board 115 is improved. It can be improved.

In the manufacturing method of the second embodiment, the first spring washer 10c is interposed in the first tightening step (S120). For this reason, the second gas sensor (specifically, the second detection unit 110) manufactured by this manufacturing method has the casing body 111, the sealing material 113, and the ceramic wiring board 115 each of which is elastic by the elastic force of the first spring washer 10c. It is a structure which presses a member in the lamination direction. The second gas sensor can be configured such that the sealing material 113 is in contact with the ceramic wiring board 115 even in a region between the plurality of wiring portions 115d. Thereby, it can suppress that a clearance gap produces between the sealing material 113 and the ceramic wiring board 115 in the area | region between several wiring parts 115d.

Therefore, according to the manufacturing method (gas sensor manufacturing method) of the second embodiment, when manufacturing the second gas sensor having the structure in which the ceramic wiring board 115 and the casing body 111 are laminated, the ceramic wiring board 115 and the casing body 111 are manufactured. (In detail, between the sealing material 113 and the ceramic wiring substrate 115) is less likely to occur, and a decrease in hermeticity can be suppressed.

In addition, according to the second gas sensor, since the sealing material 113 configured using a fluorine-based resin is used, an adverse gas (influence on gas detection is exerted from the sealing material 113 under a use condition in which the casing body 111 is at a high temperature. The gas detection accuracy can be satisfactorily obtained in combination with the effect of suppressing the decrease in airtightness.

Next, in the second detection unit 110 of the second gas sensor, the ceramic wiring substrate 115 includes a plurality of lead pins 115p protruding outward from the outermost surface different from the outermost surface on which the plurality of wiring units 115d are provided. . For this reason, the second gas sensor (specifically, the second detection unit 110) can be connected to an external device via the plurality of lead pins 115p. For example, when the second gas sensor (second detection unit 110) is stacked on the circuit board, the plurality of lead pins 115p may be electrically connected to the circuit board. In this case, since the sealing material 113 is in contact with the ceramic wiring board 115 even in the region between the plurality of wiring portions 115d, it is possible to suppress the generation of a gap between the sealing material 113 and the ceramic wiring board 115.

[2-5. Correspondence of wording]
Here, the correspondence between words will be described.

The second gas sensor or the second detection unit 110 corresponds to an example of a gas sensor, the ceramic wiring board 115 corresponds to an example of a wiring board, the wiring part 115d corresponds to an example of a wiring part, and the second element part 120 corresponds to a sensor element. The detection element of the second element unit 120 corresponds to an example of a gas detection unit. The sealing material 113 corresponds to an example of a first packing, the casing body 111 corresponds to an example of a first casing body, and the introduction pipe 111a and the discharge pipe 111b correspond to an example of a first circulation part.

[3. Other Embodiments]
As mentioned above, although embodiment of this indication was described, this indication is not limited to the above-mentioned embodiment, and can be carried out in various modes in the range which does not deviate from the gist of this indication.

For example, numerical values in the manufacturing process (such as heating temperature and heating time in the heat application process) are not limited to the above numerical values, and are arbitrary values suitable for the use and structure of the gas sensor (detection unit). May be adopted.

In the second detection unit 110 of the second embodiment, one spring washer is provided for one bolt 10a (specifically, the shaft portion 10a2). It is not restricted to such a structure. For example, the second detection unit 110 may be changed to a configuration in which two spring washers are provided for one bolt 10a (specifically, the shaft portion 10a2). Specifically, the gas sensor according to the present disclosure includes, as spring washers, a first spring washer 10c provided between the bolt head 10a1 and the laminate, and a second spring washer provided between the nut 10b and the laminate. 10d.

In the gas sensor having such a configuration, the spring washer is provided at two positions with respect to one bolt, so that the elastic force of the two spring washers (the first spring washer 10c and the second spring washer 10d) is stacked. In this structure, each member of the body (casing body 111, sealing material 113, ceramic wiring substrate 115) is pressed in the stacking direction. This gas sensor can be configured such that the sealing material 113 is in contact with the ceramic wiring board 115 even in a region between the plurality of wiring portions 115d. Thereby, it can suppress that a clearance gap produces between the sealing material 113 and the ceramic wiring board 115 in the area | region between several wiring parts 115d.

The second detection unit 110 of the second embodiment is configured to include one spring washer for one bolt 10a (specifically, the shaft portion 10a2), and includes a bolt head 10a1 and a laminated body. Although one spring washer is interposed between the two, a structure in which a spring washer is interposed between the nut 10b and the laminated body may be used.

Next, in the second detection unit 110 of the second embodiment, the laminated body includes a second packing and a second casing body in addition to the casing body 111, the sealing material 113, and the ceramic wiring board 115. You may prepare.

The second packing is made of a fluorine-based resin, and is disposed on the opposite side of the ceramic wiring substrate 115 from the sealing material 113 (first packing). A 2nd casing body is laminated | stacked on the opposite side to the ceramic wiring board 115 among 2nd packing. The second casing body has at least a second circulation part for circulating the gas to be measured. The second casing body is made of metal or ceramic. For example, the second casing body may have the same configuration as the second plate portion 12.

In this case, the ceramic wiring board 115 is provided on each of the first outermost surface on which the sealing material 113 (first packing) is laminated among the outermost surfaces and the second outermost surface on which the second packing is laminated among the outermost surfaces. A plurality of wiring portions 115d are provided. The second packing is provided in a state in which the second packing is in contact with the ceramic wiring substrate 115 even in a region between the plurality of wiring portions 115d on the surface in contact with the plurality of wiring portions 115d.

This gas sensor (second detection unit 110) has a laminated body (casing body 111 (first casing body), sealing material 113 (first packing), ceramic wiring substrate 115, second packing, second packing, and the like, by the elastic force of a spring washer. 2 casing body) is pressed in the stacking direction, and the seal material 113 (first packing) and the second packing are in contact with the ceramic wiring board 115 even in the region between the plurality of wiring portions 115d. It is a configuration. As a result, a gap is generated between the sealing material 113 (first packing) and the ceramic wiring board 115 in a region between the plurality of wiring parts 115d, or between the second packing and the ceramic wiring board 115. It can suppress that a clearance gap arises.

Therefore, according to this gas sensor, in the gas sensor having a configuration in which the casing body 111 (first casing body), the second casing body, and the ceramic wiring board 115 are stacked, the seal material 113 (first packing) and the ceramic wiring board 115 It is difficult to create a gap between the second packing and the ceramic wiring board 115, and the deterioration of the airtightness can be suppressed.

Next, the function of one component in each of the above embodiments may be shared by a plurality of components, or the function of a plurality of components may be exhibited by one component. Moreover, you may abbreviate | omit a part of structure of each said embodiment. In addition, at least a part of the configuration of each of the above embodiments may be added to or replaced with the configuration of the other above embodiments. In addition, all the aspects included in the technical idea specified from the wording described in the claims are embodiments of the present disclosure.

Claims (5)

1. A wiring board provided with a plurality of wiring parts on at least a part of the outermost surface;
   A sensor element that detects a specific component contained in the gas to be measured, and is disposed on the wiring board and electrically connected to the plurality of wiring parts;
   1st packing comprised using a fluorine-type resin, Comprising: It is laminated | stacked on the outermost surface in which the said wiring part was provided among the said wiring boards, and the cyclic | annular form by which the opening part of the magnitude | size which includes the said sensor element was formed was formed The first packing of
   A first casing body made of metal or ceramic that is laminated on the side opposite to the wiring board in the first packing, and at least a first flow part for flowing the gas to be measured is formed,
   A plurality of bolts provided so as to penetrate each member of a laminate in which at least the first casing body, the first packing, and the wiring board are laminated;
   A plurality of nuts fastened to each of the plurality of bolts;
   A gas sensor in which at least the first casing body, the first packing, and the wiring board are fixed using the bolt and the nut,
   The bolt is
   Bolt heads located outside one side of the stacking direction in the stack,
   A shaft portion that protrudes from the bolt head toward the other side in the stacking direction of the stacked body and has a smaller outer diameter than the bolt head, and is on the tip side of the shaft portion and outside the stacked body. A shaft portion to which the nut to be arranged is coupled,
   The gas sensor further includes
   A spring washer interposed between at least one of the bolt head and the laminate or between the nut and the laminate;
   With
   The first packing is provided in a state where the first packing is in contact with the wiring board even in a region between the plurality of wiring parts on a surface in contact with the plurality of wiring parts.
   Gas sensor.
2. The gas sensor according to claim 1,
   The wiring board includes a plurality of lead pins protruding outward from the outermost surface different from the outermost surface on which the plurality of wiring portions are provided,
   The plurality of lead pins are electrically connected to the plurality of wiring portions inside the wiring board,
   Gas sensor.
3. The gas sensor according to claim 1 or 2, wherein
   The spring washer includes a first spring washer provided between the bolt head and the laminate, and a second spring washer provided between the nut and the laminate.
   Gas sensor.
4. The gas sensor according to any one of claims 1 to 3,
   The laminate is
   A second packing that is configured using a fluorine-based resin and is disposed on the opposite side of the wiring packing from the first packing;
   A second casing body made of metal or ceramic that is laminated on the side opposite to the wiring board in the second packing, and at least a second flow part for flowing the gas to be measured is formed,
   With
   The wiring board includes a plurality of wiring portions on a first outermost surface of the outermost surface on which the first packing is stacked and a second outermost surface of the outermost surface on which the second packing is stacked. Is provided,
   The second packing is provided in a state in which the second packing is in contact with the wiring board even in a region between the plurality of wiring parts on a surface in contact with the plurality of wiring parts.
   Gas sensor.
5. A wiring board provided with a plurality of wiring parts on at least a part of the outermost surface;
   A sensor element that detects a specific component contained in the gas to be measured, and is disposed on the wiring board and electrically connected to the plurality of wiring parts;
   1st packing comprised using a fluorine-type resin, Comprising: It is laminated | stacked on the outermost surface in which the said wiring part was provided among the said wiring boards, and the cyclic | annular form by which the opening part of the magnitude | size which includes the said sensor element was formed was formed The first packing of
   A first casing body made of metal or ceramic that is laminated on the side opposite to the wiring board in the first packing, and at least a first flow part for flowing the gas to be measured is formed,
   A plurality of bolts provided so as to penetrate each member of a laminate in which at least the first casing body, the first packing, and the wiring board are laminated;
   A plurality of nuts fastened to each of the plurality of bolts;
   A method of manufacturing a gas sensor in which at least the first casing body, the first packing, and the wiring board are fixed using the bolt and the nut,
   The bolt is
   Bolt heads located outside one side of the stacking direction in the stack,
   A shaft portion that protrudes from the bolt head toward the other side in the stacking direction of the stacked body and has a smaller outer diameter than the bolt head, and is on the tip side of the shaft portion and outside the stacked body. A shaft portion to which the nut to be arranged is coupled,
   The gas sensor further includes
   A spring washer interposed between at least one of the bolt head and the laminate or between the nut and the laminate;
   With
   A laminated body forming step of forming a laminated body by laminating each member of the first casing body, the first packing, and the wiring board;
   At least one of the bolt head and the laminate, or between the nut and the laminate, the spring washer is interposed, and the shaft portion of the bolt is connected to each of the laminates. A first tightening step of penetrating the member, tightening the nut to the tip end side of the shaft portion, and temporarily fixing each member;
   After the first tightening step, a heat application step for applying heat to the first packing such that the first packing is softened;
   After the heat application step, a second fastening step of fastening the nut fastened to the shaft portion of the bolt again, fixing the members and holding the sensor element inside the laminated body,
   The manufacturing method of the gas sensor which has this.

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