Potentiostatic electrolytic gas sensor and method for manufacturing potentiostatic electrolytic gas sensor

Abstract

The constant potential electrolytic gas sensor (1) of the present application is characterized in that: the constant potential electrolytic gas sensor (1) is provided with a housing, the housing is provided with a housing main body (21); an electrode structure (3) including electrodes (31, 32, 33) arranged on the housing main body (21); wires (41, 42, 43) connected with the surfaces of the electrodes (31, 32, 33); and external electrodes (51, 52, 53) extending from the outside of the housing to the inside of the housing, arranged on the housing main body (21), and connected with the wires (41, 42, 43), wherein the external electrodes (51, 52, 53) are arranged in a manner that the connection positions (CP) of the external electrodes (51, 52, 53) to which the wires (41, 42, 43) are connected are located at the height corresponding to the electrode structure (3), and the housing main body (21) is provided with a guide portion (7) that guides the wires (41, 42, 43) along a guide path, the guide path is from the outside of the housing main body (21) to the electrode structure (3) through the connection positions (CP) of the external electrodes (51, 52, 53).

Description

Technical Field

[0001] This invention relates to a constant potential electrolytic gas sensor and a method for manufacturing a constant potential electrolytic gas sensor. Background Technology

[0002] As a sensor for detecting a target gas, for example, a constant-potential electrolytic gas sensor disclosed in Patent Document 1 is used. The constant-potential electrolytic gas sensor in Patent Document 1 includes: a sensor housing; a reaction electrode, a counter electrode, and a reference electrode disposed on an electrode holder within the sensor housing; three connection terminals disposed on the lower wall of the sensor housing below the electrode holder; and wires connecting each electrode to each connection terminal. In this constant-potential electrolytic gas sensor, the target gas can be detected by controlling the potential of the reaction electrode relative to the reference electrode to a constant value and by detecting the electrolytic current generated between the reaction electrode and the counter electrode using the electrochemical reaction of the target gas.

[0003] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2014-153103 Summary of the Invention In Patent Document 1, the constant-potential electrolytic gas sensor has terminals for connecting wires pressed into the lower wall of the sensor housing. The electrode holder is inserted into the sensor housing such that the wires extend through the side of the electrode holder and over the electrode holder. After the electrodes are mounted on the electrode holder, the wires are bent along the surface of each electrode and connected to that surface. Because the wires in Patent Document 1 are bent at almost right angles, wiring in this constant-potential electrolytic gas sensor is very difficult, making it difficult to manufacture and hindering the automation of the manufacturing process.

[0004] The present invention was made in view of the above problems, and its object is to provide a constant potential electrolytic gas sensor and a method for manufacturing the constant potential electrolytic gas sensor, which are easy to wire and can be easily manufactured.

[0005] The constant potential electrolytic gas sensor of the present invention is characterized by comprising: a housing having a housing body; an electrode structure including at least two electrodes disposed on the housing body; at least two wires extending along and connected to the surface of each of the at least two electrodes; and at least two external electrodes extending from the outside of the housing to the inside of the housing, disposed on the housing body, and connected to each of the at least two wires, wherein the at least two external electrodes are arranged such that the connection portions of the external electrodes connected to the wires are located at a height corresponding to the electrode structure, the housing body having a guide portion guiding the wires along an introduction path from the outside of the housing body via the connection portions of the external electrodes toward the electrode structure.

[0006] The method of the present invention is a method for manufacturing a constant potential electrolytic gas sensor, characterized in that the constant potential electrolytic gas sensor comprises: a housing having a housing body; an electrode structure including at least two electrodes disposed on the housing body; at least two wires extending along and connected to the surface of each of the at least two electrodes; and at least two external electrodes extending from the outside of the housing to the inside of the housing, disposed on the housing body, and connected to each of the at least two wires, the method comprising: a step of introducing the wires along an introduction path from the outside of the housing body through a connection portion of the external electrodes toward the electrode structure; a step of disposing the wires between the surface of the electrodes and the connection portion of the external electrodes; and a step of connecting the wires to the external electrodes at the connection portion of the external electrodes while the wires are disposed on the surface of the electrodes. Attached Figure Description

[0007] Figure 1 This is an exploded perspective view of the constant potential electrolytic gas sensor according to the first embodiment of the present invention.

[0008] Figure 2 yes Figure 1 A cross-sectional view of a constant potential electrolytic gas sensor.

[0009] Figure 3 yes Figure 1 A three-dimensional view of the housing of a constant potential electrolytic gas sensor.

[0010] Figure 4 yes Figure 1 A top view of the housing of a constant potential electrolytic gas sensor.

[0011] Figure 5 yes Figure 4 VV-line sectional view.

[0012] Figure 6 The shell body of the modified example and Figure 5 The corresponding sectional view.

[0013] Figure 7 The shell body of other variations and Figure 5 The corresponding sectional view.

[0014] Figure 8 It means in Figure 5 The housing body shown is configured with counter electrodes, and a diagram showing the state of the counter electrodes using wires is included.

[0015] Figure 9 It means in Figure 8 The diagram shows the state after which a counter electrode wire is placed between the surface of the counter electrode and the connection point of the external electrode for the counter electrode, and the state in which the counter electrode wire is connected to the external electrode for the counter electrode.

[0016] Figure 10 It means in Figure 9 The diagram shows the configuration of the reference electrode and the wires used for the reference electrode.

[0017] Figure 11 It means in Figure 10 After reaching the state shown, insert the reaction electrode wire, connect the reaction electrode wire to the external electrode of the reaction electrode, and fill the retaining structure with a protective agent as shown in the figure.

[0018] Figure 12 It means in Figure 11 The diagram shows the state after which the reaction electrodes are configured.

[0019] Figure 13 This is an exploded perspective view of the constant potential electrolytic gas sensor according to the second embodiment of the present invention.

[0020] Figure 14 yes Figure 13 A top view of the housing of a constant potential electrolytic gas sensor.

[0021] Figure 15 This is an exploded perspective view of the constant potential electrolytic gas sensor according to the third embodiment of the present invention.

[0022] Figure 16 yes Figure 15 A top view of the housing of a constant potential electrolytic gas sensor.

[0023] Explanation of reference numerals in the attached figures: 1 Constant potential electrolytic gas sensor (gas sensor), 2 Housing, 21 Housing body, 211 Base, 212 Electrode structure support, 212r Recess, 2121 Groove, 2121a Main body groove, 2121b Extension groove, 213 Intermediate support, 214 External electrode support, 214a Lower external electrode support, 214b Upper external electrode support, 22 Housing cover, 22c Capillary component, 22p Protrusion, 22r Recess, 3 Electrode structure, 31 Reaction electrode (first reaction electrode), 31a Catalyst layer, 31b Permeable sheet, 311 Second reaction electrode, 312 Third reaction electrode, 32 Counter electrode, 33 Reference electrode, 34 Electrolyte holding component for reaction electrode, 35 Electrolyte holding component for counter electrode, 36 37 Electrolyte holding component for reference electrode, 37 Electrolyte holding component for electrolyte supply, 37a Main body, 37b Extension, 38, 39 Support sheet, 4 Wire, 41 Wire for reaction electrode (wire for first reaction electrode), 411 Wire for second reaction electrode, 412 Wire for third reaction electrode, 42 Wire for counter electrode, 43 Wire for reference electrode, 5 External electrode, 51 External electrode for reaction electrode (external electrode for first reaction electrode), 511 External electrode for second reaction electrode, 512 External electrode for third reaction electrode, 52 External electrode for counter electrode, 53 External electrode for reference electrode, 6 Electrolyte, 7 Guide portion, 71 First guide portion, 72 Second guide portion, 8 Holding structure, B Bottom, CP Connection portion, CS Electrolyte storage space, H Height direction, h1 Gas inlet hole, h2 Gas outlet hole, IB Inlet side buffer membrane, OB Outlet side buffer membrane, OS Outflow-side permeable sheet, OS1 main body, OS2 extension, PA protective agent, S internal space, SS electrode structure support space (first electrode structure support space), SS1 second electrode structure support space, SS2 third electrode structure support space, W wall, W1 partition wall, WR1 first recess, WR2 second recess. Detailed Implementation

[0024] Hereinafter, a constant-potential electrolytic gas sensor according to some embodiments of the present invention will be described with reference to the accompanying drawings. However, the embodiments shown below are examples, and the constant-potential electrolytic gas sensor of the present invention is not limited to the following examples.

[0025] In this specification, the term "height direction H" is used, but for example, Figures 1-3As shown, the term "height direction H" refers to the direction perpendicular to the surface of the reaction electrode 31 or counter electrode 32 included in the electrode structure 3. Furthermore, one side of the height direction H (in the illustrated example, the side opposite to the external electrodes 51, 52, 53 at the connection points CP of the external electrodes 51, 52, 53 connected to the wires 41, 42, 43, the upper side in the figure) is designated as the upper side, and the other side of the height direction H (in the illustrated example, the side of the external electrodes 51, 52, 53 at the connection points CP of the external electrodes 51, 52, 53 connected to the wires 41, 42, 43, the lower side in the figure) is designated as the lower side. Additionally, the direction perpendicular to the height direction H is designated as the horizontal direction.

[0026] First Implementation Method like Figure 1 and Figure 2 As shown, the constant-potential electrolytic gas sensor 1 (hereinafter referred to as "gas sensor 1") of the first embodiment includes a housing 2, an electrode structure 3 housed within the housing 2, a wire 4 connected to the electrode structure 3, and an external electrode 5 connected to the wire 4. The gas sensor 1 also includes an electrolyte 6, which is disposed in contact with the electrode structure 3. The gas sensor 1 is connected to a control device (not shown), such as a potentiostat, via the external electrode 5. The gas sensor 1 applies a constant potential to the electrode structure 3 through the control device, causing an electrochemical reaction in the electrode structure 3, resulting in the generation of an electrical signal. This electrical signal is detected by the control device to detect the target gas in the ambient gas.

[0027] The gas to be detected by gas sensor 1 is not particularly limited, but examples include oxygen, hydrogen sulfide, ammonia, nitrogen dioxide, nitrogen trifluoride, chlorine, fluorine, iodine, chlorine trifluoride, ozone, hydrogen peroxide, hydrogen fluoride, hydrogen chloride (hydrochloric acid), carbon monoxide, hydrogen, sulfur dioxide, silane, disilane, phosphine, and germane. However, in this embodiment, the gas to be detected by gas sensor 1 is oxygen; an example of using gas sensor 1 as an oxygen sensor will be described below. However, the structure of the gas sensor of the present invention can be changed according to the gas to be detected.

[0028] The housing 2 is a component that houses the electrode structure 3, the wires 4, the external electrode 5 extending into the housing 2, and the electrolyte 6. For example... Figure 1 and Figure 2As shown, the housing 2 includes a housing body 21 and a housing cover 22. The housing 2 encloses the housing body 21 using the housing cover 22, forming an internal space S within it for housing the aforementioned components. Specifically, in this embodiment, by enclosing the housing body 21 using the housing cover 22, an electrolyte storage space CS for housing the electrolyte 6 is formed within the housing 2. The internal space S is liquid-tightly sealed by the breathable sheet 31b, OS, buffer membranes IB and OB (described later) in a manner that allows gas to flow in. The housing body 21 and the housing cover 22 are fixed together, for example, by known bonding methods such as ultrasonic welding or adhesives. The housing body 21 and the housing cover 22 are not particularly limited; for example, known resin materials or various types of resins can be used, and they can be formed using known resin molding and cutting techniques.

[0029] The housing body 21 is a component that supports the electrode structure 3, the wire 4, the external electrode 5, and the electrolyte 6. The housing body 21 only needs to be able to support the aforementioned components; its structure is not particularly limited. In this embodiment, as... Figures 2-4 As shown, the housing body 21 includes a base 211, an electrode structure support 212, an intermediate support 213, and multiple external electrode supports 214. The housing body 21 is integrally formed with the base 211, the electrode structure support 212, the intermediate support 213, and the external electrode supports 214. In particular, in this embodiment, the housing body 21 is integrally formed with the external electrodes 5 by insert molding. Therefore, the process of mounting the external electrodes 5 to the housing body 21 can be omitted. However, the housing body 21 can also be formed separately at each location and then fixed together.

[0030] The base 211 serves as the support for the electrode structure support 212, the intermediate support 213, and the external electrode support 214. The base 211 also supports the electrolyte 6 housed in the electrolyte storage space CS, which is formed by enclosing the main body 21 with a housing cover 22. Figures 2-4 As shown, the base 211 is formed in the shape of a flat plate (generally a circular plate in the illustrated example). An intermediate support 213 is fixed approximately at the center of the surface (upper side) of the flat plate. Multiple external electrode supports 214 are fixed along the periphery of the flat plate surface, and these external electrode supports 214 are spaced approximately equally from each other. A gas outlet hole h2 is formed in the base 211, and this gas outlet hole h2 is continuously provided through the electrode structure support 212 and the intermediate support 213. Gas flows out from the internal space S formed inside the housing 2 through the gas outlet hole h2 continuously formed in the electrode structure support 212, the intermediate support 213, and the base 211.

[0031] The electrode structure support portion 212 is the part that supports the electrode structure 3 and the wire 4 connected to the electrode structure 3. The electrode structure support portion 212 is supported on the base 211 by an intermediate support portion 213 and an external electrode support portion 214. Figures 2-4 As shown, the electrode structure support portion 212 is formed in the shape of a flat plate. A central support portion 213 is fixed approximately at the center of the bottom surface (lower side) of the flat plate. Multiple external electrode supports 214 are fixed along the periphery of the flat plate, and these multiple external electrode supports 214 are spaced approximately equally from each other. Above approximately the center of the flat plate surface of the electrode structure support portion 212, an electrode structure support space SS (see reference SS) is formed, enclosed by the multiple external electrode supports 214, for supporting the electrode structure 3. Figure 1 and Figure 3 A recess 212r with an outflow-side buffer membrane OB is formed on the surface of the electrode structure support portion 212 below the electrode structure support space SS. A gas outflow hole h2 is formed below the recess 212r, which is continuously provided in the intermediate support portion 213 and the base portion 211.

[0032] The outflow-side buffer membrane OB, located in the recess 212r of the electrode structure support 212, together with the outflow-side permeable sheet OS, suppresses the outflow of electrolyte 6 through the gas outflow hole h2 and also functions to adjust the pressure inside the housing 2. Figure 2 As shown, the outflow-side buffer membrane OB is held within the recess 212r by closing the opening of the recess 212r of the electrode structure support portion 212 through the outflow-side permeable sheet OS. The outflow-side buffer membrane OB can be a membrane that inhibits liquid flow and allows gas flow, for example, a porous membrane made of a fluoropolymer such as polytetrafluoroethylene (PTFE).

[0033] The gas-permeable sheet OS on the outflow side, together with the buffer membrane OB on the outflow side, liquid-tightly seals the gas outflow hole h2 of the electrode structure support 212. For example... Figure 1 As shown, the outflow-side permeable sheet OS comprises a sheet-like (generally circular in the illustrated example) main body OS1 and multiple (four in the illustrated example) sheet-like (generally rectangular in the illustrated example) extensions OS2 that protrude outward from the main body OS1 and are arranged at approximately equal intervals in the circumferential direction of the main body OS1. The main body OS1 is disposed within the electrode structure support space SS above the electrode structure support 212. The extensions OS2 are arranged such that they extend along the surface of the electrode structure support 212 through the gap between adjacent external electrode supports 214, 214, as shown in the figure. Figure 2As shown, the electrode structure support portion 212 is bent at its outer edge and extends into the electrolyte receiving space CS. The outflow-side permeable sheet OS is annularly heat-fused to the surface of the electrode structure support portion 212, located outside the outer periphery of the recess 212r of the electrode structure support portion 212, thereby fixing it to the surface of the electrode structure support portion 212 in a manner that closes the recess 212r. The outflow-side permeable sheet OS can be a sheet that inhibits liquid flow while allowing gas flow, for example, a porous sheet made of a fluoropolymer such as polytetrafluoroethylene (PTFE).

[0034] The intermediate support portion 213 is the part that supports the electrode structure support portion 212 on the base portion 211. For example... Figure 2 As shown, the intermediate support portion 213 is formed in a columnar shape, extending approximately from the center of the flat surface of the base portion 211 along the height direction H. Its lower end is fixed to the base portion 211 in the height direction H, and its upper end is fixed to the electrode structure support portion 212 in the height direction H. A gas outlet hole h2 is formed in the intermediate support portion 213, which extends continuously from the electrode structure support portion 212 through the intermediate support portion 213, through the base portion 211.

[0035] The external electrode support 214 supports the external electrode 5 and the wire 4 connected to the external electrode 5. The external electrode support 214 also supports the electrode structure support 212 on the base 211. Figure 3 As shown, the external electrode support 214 is formed as a column extending along the height direction H from near the periphery of the flat surface of the base 211. It is fixed to the base 211 at its lower end in the height direction H and to the electrode structure support 212 at its middle position in the height direction H. An external electrode 5 is fixed to the external electrode support 214, extending along the height direction H and penetrating the external electrode support 214. Multiple external electrode supports 214 are provided depending on the required number of external electrodes 5 (three in the illustrated example), and these multiple external electrode supports 214 are arranged at approximately equal intervals along the periphery of the flat surface of the base 211. Furthermore, in the illustrated example, a support portion with approximately the same shape as the external electrode support 214 but not supporting the external electrode 5 is provided. Four support portions, including this support portion, are arranged at approximately equal intervals along the periphery of the flat surface of the base 211.

[0036] like Figure 3As shown, the external electrode support 214 includes a lower external electrode support 214a located below the electrode structure support 212 in the height direction H, and an upper external electrode support 214b located above the electrode structure support 212 in the height direction H. The lower external electrode support 214a supports the external electrode 5 and also supports the electrode structure support 212. The upper external electrode support 214b supports the external electrode 5 and positions the connection portion CP of the external electrode 5 to the wire 4 (e.g., the upper end of the external electrode 5) at a height corresponding to the electrode structure 3. The connection portion CP of the external electrode 5 is provided on the upper external electrode support 214b. Correspondingly, the upper external electrode support 214b may also include a guide portion 7 for guiding the wire 4 and a retaining structure portion 8 for retaining a protective agent for protecting the connection portion CP of the external electrode 5. Details of the guide portion 7 and the retaining structure portion 8 are described in detail below.

[0037] like Figure 3 and Figure 4 As shown, the upper external electrode support portion 214b, when viewed from the height direction H, is formed in a roughly fan shape with its radially inner portion cut into approximately concentric circles. Thus, on the surface of the electrode structure support portion 212, which is horizontally inner than the upper external electrode support portion 214b, the electrode structure support space SS, which supports the electrode structure 3, is formed in a roughly cylindrical shape by being surrounded by multiple upper external electrode support portions 214b. The upper external electrode support portions 214b surrounding the electrode structure support space SS restrict the electrode structure 3 supported within the electrode structure support space SS from disengaging horizontally outward from the electrode structure support space SS. The multiple upper external electrode support portions 214b are arranged approximately equally spaced apart from each other along the periphery of the electrode structure support space SS. A gap extending from approximately the center of the flat surface of the electrode structure support portion 212 along the periphery is formed between adjacent upper external electrode support portions 214b. This gap is formed as an extension OS2 of the aforementioned outflow-side permeable sheet OS (see reference). Figure 1 ), and the extension 37b of the electrolyte supply electrolyte holding member 37 included in the electrode structure 3 (described later) (see Figure 1 The corresponding dimensions. The outflow-side permeable sheet OS and the electrolyte supply holding component 37 are disposed in the gap via their respective extensions OS2, 37b, thereby restricting their rotational movement around an axis extending in the height direction H.

[0038] The housing cover 22 is a component that closes the housing body 21 by forming an internal space S within the housing 2. In this embodiment, as... Figure 1 and Figure 2As shown, the housing cover 22 is formed as a cylinder closed at one end (the upper end). The housing cover 22 is fixed to the base 211 of the housing body 21 in such a way that it covers the electrode structure support 212, the intermediate support 213, and the outer electrode support 214 of the housing body 21 inside the cylinder. If the housing body 21 is closed by the housing cover 22, an internal space S is formed, and an electrolyte storage space CS is formed between the inner side of the housing cover 22 and the base 211 of the housing body 21 and the electrode structure support 212.

[0039] like Figure 1 and Figure 2 As shown, a capillary component 22c is fixed to the wall (upper wall) of one end of the housing 22 using an adhesive or an elastic material (pad, thermoplastic elastomer, etc.). This capillary component 22c has a gas inlet hole h1. Gas containing the target gas from outside the housing 2 flows into the reaction electrode 31 inside the housing 2 via the gas inlet hole h1. Here, in order to minimize the signal intensity when the electrode structure 3 detects the target gas, the gas inlet hole h1 needs to be configured to limit the amount of target gas flowing into the housing 2 to below a predetermined amount. To achieve this, the aperture of the gas inlet hole h1 needs to be formed to be extremely small (e.g., 50 μm φ). As shown in this embodiment, for example, when the housing 22 is formed into a closed-end cylindrical shape by resin molding, it is difficult to simultaneously provide such a fine gas inlet hole on the wall of one end of the housing 22 during resin molding. By fixing the capillary component 22c, which is pre-inserted with a fine gas inlet hole h1, to the molded housing cover 22, the fine gas inlet hole h1 can be easily provided in the housing cover 22.

[0040] like Figure 2 As shown, a recess 22r is formed on the inner side of the upper wall of the housing 22, and an inflow-side buffer membrane IB is disposed in this recess 22r. The inflow-side buffer membrane IB disposed in the recess 22r has the following functions: together with the breathable sheet 31b described later, it inhibits the outflow of electrolyte 6 through the gas inlet hole h1, and adjusts the pressure inside the housing 2. The inflow-side buffer membrane IB is fixed to the recess 22r of the housing 22, for example, by a known fixing method such as a dollop-shaped double-sided tape. The inflow-side buffer membrane IB can be a membrane that inhibits the passage of liquid and allows the passage of gas, for example, a porous membrane made of a fluoropolymer such as polytetrafluoroethylene (PTFE).

[0041] The electrode structure 3 detects the target gas by undergoing an electrochemical reaction related to the target gas in the electrolyte 6. The electrode structure 3 is disposed within the housing body 21, but its arrangement is not particularly limited. In this embodiment, as... Figures 1-4As shown, the electrode structure 3 is disposed within the electrode structure support space SS formed on the electrode structure support portion 212, and is sandwiched between the electrode structure support portion 212 and the upper wall of the housing cover 22, thereby being supported within the housing 2. The electrode structure 3 is formed to correspond to the dimensions of the electrode structure support space SS, and the electrode structure 3 is restricted from detaching from the horizontal direction of the electrode structure support space SS by a plurality of external electrode supports 214 disposed around the electrode structure support space SS. Furthermore, in Figure 3 and Figure 4 In order to make it easier to observe the configuration of electrodes 31, 32 and 33 in electrode structure 3, the illustrations of other constituent elements contained in electrode structure 3 are omitted.

[0042] In this embodiment, such as Figure 1 and Figure 2 As shown, the electrode structure 3 includes: a reaction electrode 31 in which an electrochemical reaction related to the target gas occurs; a counter electrode 32 in which another electrochemical reaction corresponding to the electrochemical reaction related to the target gas occurs; and a reference electrode 33 serving as a reference for the potential of the reaction electrode 31. The reaction electrode 31, the counter electrode 32, and the reference electrode 33 are arranged in contact with the electrolyte 6 and electrically connected to an external electrode 5 via a wire 4. Furthermore, the electrode structure 3 can be configured to detect the target gas through an electrochemical reaction related to the target gas; to achieve this, it is sufficient to have at least two electrodes, namely the reaction electrode 31 and the counter electrode 32.

[0043] The reaction electrode 31 only needs to be capable of undergoing an electrochemical reaction related to the target gas in the electrolyte 6; its structure and configuration are not particularly limited. In this embodiment, such as Figure 1 and Figure 2 As shown, the reaction electrode 31 comprises: a thin-film catalyst layer 31a having a surface substantially perpendicular to the height direction H (in the illustrated example, a substantially circular thin-film), and a permeable sheet 31b supporting the catalyst layer 31a. The reaction electrode 31 is fixed to the housing cover 22 via the permeable sheet 31b. The reaction electrode 31 is assembled to the electrode structure 3 by closing the housing body 21 through the housing cover 22. A reference electrode 33 and a counter electrode 32 are sequentially stacked below the reaction electrode 31 in the height direction H, spaced apart from the reaction electrode 31. A reaction electrode wire 41, described later, is connected to the surface of the catalyst layer 31a of the reaction electrode 31. The reaction electrode 31 is formed by forming the catalyst layer 31a on the permeable sheet 31b using, for example, a known electrode material such as platinum, through known film-forming techniques such as coating, vapor deposition, or sputtering. The catalyst layer 31a of the reaction electrode 31 is formed in a manner that has approximately the same shape and surface area (area of ​​the surface facing the height direction H) as the counter electrode 32 and the reference electrode 33.

[0044] The permeable sheet 31b of the reaction electrode 31, together with the inflow-side buffer membrane IB, liquid-tightly seals the gas inflow hole h1. For example... Figure 2 As shown, the breathable sheet 31b is fixed to the housing cover 22 by heat-fusion bonding to the annular protrusion 22p provided on the outer periphery of the recess 22r of the housing cover 22, thereby closing the recess 22r. The breathable sheet 31b is configured to inhibit the passage of liquid and allow the passage of gas, for example, it is configured as a porous sheet made of fluororesin such as polytetrafluoroethylene (PTFE).

[0045] The counter electrode 32 only needs to be capable of undergoing other electrochemical reactions corresponding to the electrochemical reactions related to the target gas; its structure and configuration are not particularly limited. In this embodiment, such as... Figure 1 and Figure 2 As shown, the counter electrode 32 is formed as a thin film (in the illustrated example, a roughly circular thin film) having a surface substantially perpendicular to the height direction H, and is disposed on the main body OS1 of the outflow-side permeable sheet OS. Above the counter electrode 32, along the height direction H, a reference electrode 33 and a reaction electrode 31 are sequentially stacked at intervals from the counter electrode 32. However, the counter electrode 32 may also be arranged at a position substantially the same height as the reaction electrode 31 or the reference electrode 33 in the height direction H. A counter electrode wire 42, described later, is connected to the surface of the counter electrode 32. The counter electrode 32 is supported on the outflow-side permeable sheet OS by being pressed by the housing cover 22 via the constituent elements on the counter electrode 32. The counter electrode 32, for example, like the reaction electrode 31, can be formed by depositing a known electrode material such as platinum on a permeable sheet (not shown) of the same type as the permeable sheet 31b using a known film-forming technique.

[0046] The reference electrode 33 is only required to serve as a reference for the potential of the reaction electrode 31, and its structure and arrangement are not particularly limited. In this embodiment, the reference electrode 33 is formed as a thin film (in the illustrated example, a roughly circular thin film) having a surface substantially perpendicular to the height direction H, and is stacked between the reaction electrode 31 and the counter electrode 32 along the height direction H, spaced apart from the reaction electrode 31 and the counter electrode 32, respectively. However, the reference electrode 33 may also be arranged at a position substantially at the same height as the reaction electrode 31 or the counter electrode 32 in the height direction H. A reference electrode wire 43, described later, is connected to the surface of the reference electrode 33. The reference electrode 33 is supported between the reaction electrode 31 and the counter electrode 32 by being held between the upper and lower components in the height direction H of the reference electrode 33. For example, the reference electrode 33, like the reaction electrode 31, can be formed on a permeable sheet (not shown) of the same type as the permeable sheet 31b by a known film-forming technique using a known electrode material such as platinum.

[0047] In the gas sensor 1 of this embodiment, a constant voltage is applied to the reaction electrode 31 based on the potential of the reference electrode 33 by a control device (not shown) such as a potentiostat connected to the external electrode 5, thus adding a constant potential difference between the reaction electrode 31 and the reference electrode 33. When the target gas flows into the reaction electrode 31, an electrochemical reaction related to the target gas occurs in the reaction electrode 31, which has a constant potential difference added between it and the reference electrode 33. If an electrochemical reaction related to the target gas occurs, other electrochemical reactions also occur on the counter electrode 32 side corresponding to this electrochemical reaction. As a result of the electrochemical reactions occurring in the reaction electrode 31 and the counter electrode 32, an electrolytic voltage is generated between the reaction electrode 31 and the counter electrode 32, and an electrolytic current flows through it. By detecting the electrolytic current at this time, the target gas can be detected, and the concentration of the target gas can be determined based on the magnitude of the electrolytic current.

[0048] The reaction electrode 31, counter electrode 32, and reference electrode 33 of the electrode structure 3 can be configured to at least contact the electrolyte 6, and the method of contact with the electrolyte 6 is not particularly limited. In this embodiment, as... Figure 1 and Figure 2 As shown, the electrode structure 3 includes electrolyte holding components 34, 35, 36, and 37 capable of holding the electrolyte 6. The reaction electrode 31, the counter electrode 32, and the reference electrode 33 are arranged in contact with the electrolyte 6 held in the electrolyte holding components 34, 35, 36, and 37 via the electrolyte holding components 34, 35, 36, and 37. However, the reaction electrode 31, the counter electrode 32, and the reference electrode 33 can also be arranged in direct contact with the electrolyte 6.

[0049] Electrolyte holding components 34, 35, 36, and 37 are configured to hold the electrolyte 6 and bring the held electrolyte 6 into contact with the reaction electrode 31, the counter electrode 32, and the reference electrode 33. In this embodiment, as... Figure 1 and Figure 2As shown, the electrolyte holding components include an electrolyte holding component 34 for the reaction electrode, an electrolyte holding component 35 for the counter electrode, an electrolyte holding component 36 for the reference electrode, and an electrolyte holding component 37 for electrolyte supply. The electrolyte holding components 34, 35, 36, and 37 are arranged in contact with each other, so that the reaction electrode 31, the counter electrode 32, and the reference electrode 33 are indirectly connected to each other via the held electrolyte 6. The main body 37a of the electrolyte holding components 34, 35, 36, and 37 (described later) are formed to have substantially the same shape and size, and have the largest surface area (area of ​​the surface facing the height direction H) among the constituent elements of the electrode structure 3, defining the outer edge of the electrode structure 3. Furthermore, in Figure 2 In order to make the layered structure of electrode structure 3 easy to understand, the electrolyte holding components 34, 35, 36, 37 (especially electrolyte holding components 34, 36, 37) are shown separately from each other, but in fact the annular portions of each electrolyte holding component 34, 35, 36, 37 extending outward toward each electrode 31, 32, 33 are in contact with each other.

[0050] like Figure 1 and Figure 2 As shown, the electrolyte holding member 34 for the reaction electrode is in contact with the reaction electrode 31, so that the held electrolyte 6 is in contact with the reaction electrode 31. The electrolyte holding member 34 for the reaction electrode is formed in the shape of a thin sheet (in the illustrated example, it is a generally circular thin sheet), and is arranged between the reaction electrode 31 and the reference electrode 33 in the height direction H, in such a way that it is in surface contact with the surface of the reaction electrode 31. The electrolyte holding member 34 for the reaction electrode has a larger surface area (area of ​​the surface facing the height direction H) than each electrode 31, 32, 33. The electrolyte holding member 34 for the reaction electrode is arranged in such a way that a portion extending in a ring shape outside the surface facing each electrode 31, 32, 33 is in contact with the electrolyte holding member 36 for the reference electrode. The electrolyte holding member 34 for the reaction electrode supplies electrolyte 6 from the electrolyte holding member 36 for the reference electrode through contact with the electrolyte holding member 36 for the reference electrode. Furthermore, the electrolyte holding member 34 for the reaction electrode is a generally circular sheet in the illustrated example, but it may also be the same as the electrolyte holding member 37 for electrolyte supply described later, having a sheet-like (e.g., a generally circular sheet-like) main body and a plurality (e.g., four) sheet-like (e.g., a generally rectangular sheet-like) extensions that protrude outward from the main body and are arranged at approximately equal intervals to each other in the circumferential direction of the main body.

[0051] like Figure 1 and Figure 2As shown, the electrolyte holding member 35 for the counter electrode is in contact with the counter electrode 32, and the held electrolyte 6 is in contact with the counter electrode 32. Additionally, as... Figure 1 and Figure 2 As shown, the electrolyte holding member 35 for the counter electrode is arranged in such a way that it contacts the surface of the counter electrode 32 and the main body 37a of the electrolyte supply holding member 37 in the height direction H. The electrolyte holding member 35 for the counter electrode has a larger surface area (area of ​​the surface facing the height direction H) than each of the electrodes 31, 32, and 33. The electrolyte holding member 35 for the counter electrode supplies electrolyte 6 from the electrolyte supply holding member 37 by contacting the main body 37a of the electrolyte supply holding member 37. Furthermore, the electrolyte holding member 35 for the counter electrode is a generally circular sheet in the illustrated example, but it may also be the same as the electrolyte holding member 37 for electrolyte supply described later, having a sheet-like (e.g., a generally circular sheet-like) main body and a plurality (e.g., four) sheet-like (e.g., a generally rectangular sheet-like) extensions that protrude from the main body in the outward direction and are arranged at approximately equal intervals to each other in the circumferential direction of the main body.

[0052] like Figure 1 and Figure 2 As shown, the reference electrode electrolyte holding member 36 is in contact with the reference electrode 33, and the held electrolyte 6 is also in contact with the reference electrode 33. The reference electrode electrolyte holding member 36 is formed in the shape of a sheet (in the illustrated example, it is a generally circular sheet) and is arranged to contact the surface of the reference electrode 33 between the reaction electrode 31 and the reference electrode 33 in the height direction H. The reference electrode electrolyte holding member 36 has a larger surface area (area of ​​the surface facing the height direction H) than each electrode 31, 32, 33. The reference electrode electrolyte holding member 36 is arranged to contact the main body 37a of the reaction electrode electrolyte holding member 34 and the electrolyte supply electrolyte holding member 37 in a ring-shaped extension outside the surface facing each electrode 31, 32, 33. The reference electrode electrolyte holding member 36 supplies electrolyte 6 from the main body 37a of the electrolyte supply holding member 37 through contact with the main body 37a of the reaction electrode electrolyte holding member 34 and the electrolyte supply holding member 37, and supplies electrolyte 6 to the reaction electrode electrolyte holding member 34. Furthermore, in the illustrated example, the reference electrode electrolyte holding member 36 is a generally circular sheet, but it may also be similar to the electrolyte supply holding member 37 described later, having a sheet-like (e.g., a generally circular sheet-like) main body and multiple (e.g., four) sheet-like (e.g., generally rectangular sheet-like) extensions that protrude outwards from the main body and are arranged approximately equally spaced from each other in the circumferential direction of the main body.

[0053] The electrolyte supply electrolyte holding member 37 is in direct contact with the electrolyte 6 in the electrolyte storage space CS, allowing the electrolyte 6 in the electrolyte storage space CS to permeate into the electrolyte supply electrolyte holding member 37, and supplying the permeated electrolyte 6 to other electrolyte holding members 34, 35, and 36. The electrolyte supply electrolyte holding member 37 has a sheet-like (generally circular sheet-like in the illustrated example) main body 37a that forms part of the electrode structure 3, and a plurality of sheet-like (generally rectangular sheet-like in the illustrated example) extensions 37b that protrude outward from the main body 37a and are arranged at approximately equal intervals around the main body 37a in the circumferential direction. The electrolyte supply electrolyte holding member 37 is formed to have approximately the same shape and size as the outflow side permeable sheet OS, and is arranged to overlap the outflow side permeable sheet OS with the counter electrode 32 and the counter electrode electrolyte holding member 35 sandwiched between them.

[0054] like Figure 1 and Figure 2 As shown, the extension 37b of the electrolyte supply holding member 37 extends along the surface of the electrode structure support 212 through the gap between adjacent external electrode supports 214, 214, and bends at the outer edge of the electrode structure support 212 to extend into the electrolyte storage space CS. The extension 37b extending into the electrolyte storage space CS is in direct contact with the electrolyte 6 in the electrolyte storage space CS, so as to supply the electrolyte 6 from the extension 37b to the main body 37a.

[0055] Each electrolyte holding component 34, 35, 36, and 37 is made of a material that is electrically insulating and absorbent, without any particular limitation. For example, it can be made of filter paper formed from silica fiber, cellulose fiber, glass fiber, etc.

[0056] like Figure 1 and Figure 2As shown, the electrode structure 3 may also include support sheets 38 and 39. The support sheets 38 and 39 are stacked within the electrode structure 3 to press the reaction electrode wire 41, the counter electrode wire 42, and the reference electrode wire 43 to the reaction electrode 31, the counter electrode 32, and the reference electrode 33, respectively, to suppress poor contact between them. The support sheets 38 and 39 are each formed into sheets with a specified rigidity (generally circular sheets in the illustrated example) and are stacked between the reaction electrode electrolyte holding member 34 and the reference electrode electrolyte holding member 36 in the height direction H, and between the reference electrode 33 and the electrolyte supply electrolyte holding member 37 in the height direction H. The support sheets 38 and 39 are formed with a surface area (area of ​​the surface facing the height direction H) slightly larger than that of the reaction electrode 31, counter electrode 32, and reference electrode 33, and are configured to apply pressure to the entire surface of each of the reaction electrode 31, counter electrode 32, and reference electrode 33. Furthermore, the support sheets 38 and 39 are configured to have a surface area (area of ​​the surface facing the height direction H) smaller than that of the main body 37a of the electrolyte holding member 34 for the reaction electrode, the electrolyte holding member 36 for the reference electrode, and the electrolyte holding member 37 for electrolyte supply, thereby not hindering contact between the respective electrolyte holding members. The support sheets 38 and 39 can be formed, for example, of polyethylene naphthalate (PEN).

[0057] Electrolyte 6 is a conductive solution that comes into contact with electrode structure 3 and undergoes an electrochemical reaction related to the target gas. In this embodiment, as... Figure 2 As shown, the electrolyte 6 is housed in the electrolyte storage space CS within the housing 2 in a manner that it contacts the electrode structure 3 via electrolyte holding components 34, 35, 36, and 37. The electrolyte 6 can be appropriately selected based on the type of gas to be detected and the type of electrode structure 3 used for detection. For example, acidic aqueous solutions such as sulfuric acid and phosphoric acid, or neutral salt solutions such as lithium bromide and calcium chloride can be used. Alternatively, the electrolyte 6 can be a molten salt that is liquid at room temperature and mainly consists of nitrogen-containing aromatic cations or aliphatic onium cations and fluoride anions. The nitrogen-containing aromatic cations can be, for example, alkyl imidazole ions or alkylpyridinium ions. The fluoride anions can be, for example, borofluoride ions, phosphorus fluoride ions, or trifluoromethanesulfonic acid ions.

[0058] The wire 4 is a component that electrically connects the electrode structure 3 to the external electrode 5. In this embodiment, as... Figure 1 and Figure 2As shown, corresponding to the reaction electrode 31, counter electrode 32, and reference electrode 33 of the electrode structure 3, a reaction electrode wire 41, a counter electrode wire 42, and a reference electrode wire 43 are provided as wires 4. The reaction electrode wire 41, the counter electrode wire 42, and the reference electrode wire 43 extend along each surface of the reaction electrode 31, the counter electrode 32, and the reference electrode 33 at one end and are electrically connected to each surface of the reaction electrode 31, the counter electrode 32, and the reference electrode 33. Furthermore, the reaction electrode wire 41, the counter electrode wire 42, and the reference electrode wire 43 are electrically connected at their other ends to each of the external electrodes 5 (described later as reaction electrode external electrode 51, counter electrode external electrode 52, and reference electrode external electrode 53).

[0059] The wires 41, 42, and 43 are formed into wire or strip shapes, for example, by metals such as platinum, gold, tungsten, and tantalum. Furthermore, while this embodiment provides three wires 41, 42, and 43, as described above, the gas sensor 1 only needs to have at least two electrodes, namely the reaction electrode 31 and the counter electrode 32. Correspondingly, it only needs to have at least two wires, namely the reaction electrode wire 41 and the counter electrode wire 42.

[0060] An external electrode 5 applies a voltage from a control device (not shown) such as a potentiostat located outside the housing 2 to an electrode structure 3 located inside the housing 2, which is used to induce an electrochemical reaction related to the target gas. The electrical signal generated by the electrochemical reaction related to the target gas is then transmitted from the electrode structure 3 to the control device. In this embodiment, as... Figure 1 As shown, corresponding to the reaction electrode 31, counter electrode 32, and reference electrode 33 of the electrode structure 3, external electrodes 51 for the reaction electrode, 52 for the counter electrode, and 53 for the reference electrode are provided as external electrodes 5. The external electrodes 51, 52, and 53 extend from the outside of the housing 2 toward the inside of the housing 2 and are disposed on the housing body 21. More specifically, the external electrodes 51, 52, and 53 extend along the height direction H from below the base 211 of the housing body 21 and are disposed on the external electrode support 214 of the housing body 21, protruding upwards toward the external electrode support 214. The external electrodes 51, 52, and 53 are electrically connected at one end (the portion protruding upwards from the external electrode support 214) to each of the reaction electrode wire 41, the counter electrode wire 42, and the reference electrode wire 43 (see reference). Figure 3 On the other end (the portion protruding downwards from the base 211), it is electrically connected to a control device (not shown). In this embodiment, as... Figure 4As shown, the external electrodes 51, 52, and 53 are configured such that, in a horizontal direction substantially perpendicular to the line connecting the external electrode 52 for the counter electrode and the external electrode 53 for the reference electrode, the external electrode 51 for the reaction electrode is located approximately at the midpoint between the external electrode 52 for the counter electrode and the external electrode 53 for the reference electrode. Furthermore, in this embodiment, each of the external electrodes 51, 52, and 53 is provided to extend along the height direction H, but it may also be provided to extend in a direction different from the height direction H, such as the horizontal direction.

[0061] like Figure 5 As shown, the external electrodes 51, 52, and 53 are arranged such that the connection points CP of the external electrodes 51, 52, and 53 connected to the wires 41, 42, and 43 are located at a height corresponding to that of the electrode structure 3. Therefore, when connecting the electrodes 31, 32, and 33 of the electrode structure 3 to the external electrodes 51, 52, and 53 using the wires 41, 42, and 43, it is only necessary to route the wires 41, 42, and 43 in a generally horizontal direction, without the need for significant bending. This allows for easy routing of the wires 41, 42, and 43, and facilitates the manufacture of the gas sensor 1. Furthermore, since it is not necessary to significantly bend the wires 41, 42, and 43, the risk of wire breakage due to applying load to the bent portions of the wires 41, 42, and 43 is reduced. Furthermore, in this specification, "corresponding height" refers to a position in the height direction H that is approximately the same as that of the comparison object (e.g., electrode structure 3, electrodes 31, 32, 33) relative to the reference position of the housing body 21 (e.g., the surface of the base 211, electrode structure support 212). However, it is not limited to this and may also include a position that deviates from the comparison object in the height direction H by an amount of length in the height direction H. The connection portion CP of the external electrodes 51, 52, 53 at the height corresponding to the electrode structure 3 means that the connection portion CP of at least one of the external electrodes 51, 52, 53 is located at a height corresponding to the range in the height direction H of the electrode structure 3. For example, the connection portion CP of at least one of the external electrodes 51, 52, 53 may be located at a height corresponding to any one of the electrodes 31, 32, 33 included in the electrode structure 3, and the connection portion CP of each of the external electrodes 51, 52, 53 may also be located at a height corresponding to the electrodes 31, 32, 33 corresponding to each of the external electrodes 51, 52, 53.

[0062] In this embodiment, such as Figure 5As shown, the external electrodes 51, 52, and 53 are arranged such that the height (position in the height direction H) of the connection points CP of the external electrodes 51, 52, and 53 is approximately the same as that of each other. Therefore, by changing the arrangement height of the corresponding wires 41, 42, and 43 according to the external electrodes 51, 52, and 53, it is not necessary to bend the wires 41, 42, and 43. Thus, wiring of the wires 41, 42, and 43 can be easily performed, and the gas sensor 1 can be easily manufactured. In this embodiment, as... Figure 5 As shown, the connection points CP of the external electrodes 51, 52, and 53, which are at approximately the same height, are located at the height corresponding to the reaction electrode 31 of the electrode structure 3. However, at least one of the connection points CP of the external electrodes 51, 52, and 53 may be located at the height corresponding to the electrode structure 3, or they may be different from each other.

[0063] The external electrodes 51, 52, and 53 are formed into rod shapes using metals such as platinum, gold, tungsten, and tantalum. Furthermore, while this embodiment provides three external electrodes 51, 52, and 53, as described above, the gas sensor 1 can have at least two electrodes, namely the reaction electrode 31 and the counter electrode 32. Correspondingly, it can have at least two external electrodes, namely the external electrode 51 for the reaction electrode and the external electrode 52 for the counter electrode.

[0064] In this embodiment, as Figure 3 and Figure 4As shown, the housing body 21 includes a guide portion 7 that guides wires 41, 42, and 43 along an introduction path that extends from the outside of the housing body 21 through the connection points CP of the external electrodes 51, 52, and 53 toward the electrode structure 3. Therefore, when connecting the electrodes 31, 32, and 33 of the electrode structure 3 to the external electrodes 51, 52, and 53 using wires 41, 42, and 43, it is easy to route the wires 41, 42, and 43 from the outside of the housing body 21 to between the connection points CP of the external electrodes 51, 52, and 53 and the electrodes 31, 32, and 33 of the electrode structure 3, thus facilitating the manufacture of the gas sensor 1. The guide portion 7 is configured such that the introduction path is located at a height corresponding to the connection points CP of the external electrodes 51, 52, and 53 positioned at corresponding heights as well as the height of the electrode structure 3. Therefore, when wires 41, 42, and 43 are introduced from outside the housing body 21 and positioned between the electrode structure 3 and the connection points CP of the external electrodes 51, 52, and 53, wires 41, 42, and 43 can be introduced in a generally horizontal direction, and the positioning of wires 41, 42, and 43 in the height direction H can be easily achieved. Furthermore, the positions of the connection points CP and electrode structures 3 described in the phrase "introduction path from the connection points CP of the external electrodes 51, 52, and 53 toward the electrode structure 3" include not only the positions of the connection points CP and electrode structures 3 already positioned when guiding wires 41, 42, and 43, but also the hypothetical positions of the connection points CP and electrode structures 3 positioned after guiding wires 41, 42, and 43. In this embodiment, as described above, the guide portion 7 is provided on the upper external electrode support portion 214b above the connection points CP where the external electrodes 51, 52, and 53 are positioned. However, the guide section 7 can be configured to guide the wires 41, 42, and 43 along the aforementioned guide path, or it can be provided on a part of the housing body 21 other than the upper external electrode support section 214b.

[0065] The guide portion 7 is only required to guide the wires 41, 42, and 43 along the guide path from the outside of the housing body 21 through the connection points CP of the external electrodes 51, 52, and 53 toward the electrode structure 3; its structure is not particularly limited. In this embodiment, as... Figure 3 and Figure 4As shown, the guide portion 7 includes a first guide portion 71 that guides wires 41, 42, and 43 from the outside of the housing body 21 toward the connection portions CP of the external electrodes 51, 52, and 53, and a second guide portion 72 that guides wires 41, 42, and 43 from the connection portions CP of the external electrodes 51, 52, and 53 toward the electrode structure 3. In this way, the first and second guide portions 71 and 72 are provided on both sides of the connection portions CP of the external electrodes 51, 52, and 53 along the guide path from the outside of the housing body 21 toward the electrode structure 3, thereby enabling more accurate wiring of wires 41, 42, and 43 at the connection portions CP of the external electrodes 51, 52, and 53. Furthermore, in this embodiment, the first and second guide portions 71 and 72 are arranged in a substantially straight line along the guide path from the outside of the housing body 21 through the connection portions CP of the external electrodes 51, 52, and 53 toward the electrode structure 3. Therefore, when wires 41, 42, and 43 are arranged between the connection points CP of the external electrodes 51, 52, and 53 and the electrode structure 3, they can be arranged while maintaining a generally straight shape, making it easier to arrange the wires 41, 42, and 43. For example, when wires 41, 42, and 43 are introduced from outside the housing body 21, they can be introduced at a predetermined length, that is, a length corresponding to the distance between each electrode 31, 32, and 33 of the electrode structure 3 and each connection point CP of the external electrodes 51, 52, and 53, or they can be introduced at a length longer than the predetermined length and then cut after being connected to the connection points CP of the external electrodes 51, 52, and 53. In the latter case, for example, the wires 41, 42, and 43 wound on the spool are guided in the order of the first guide 71 and the second guide 72. When the tips of the wires 41, 42, and 43 reach the electrode structure 3, the wires 41, 42, and 43 are fixed to the outside of the first guide 71 (outer side of the housing body 21) and the outside of the second guide 72 (on the electrode structure 3 side) using clamps or the like. After the wires 41, 42, and 43 are joined to the external electrodes 51, 52, and 53 at each connection point CP by welding or the like, they are cut off on the outside of the first guide 71 or between the first guide 71 and each connection point CP, thereby enabling the wires 41, 42, and 43 to be positioned in a predetermined location. In this way, positional deviation of the wires 41, 42, and 43 can be suppressed, and the wiring of the wires 41, 42, and 43 can be automated.

[0066] In this embodiment, such as Figure 5As shown, the first guide portion 71 is positioned at a height corresponding to the connection portion CP of the external electrodes 51, 52, and 53. More specifically, the bottom surface of the first guide portion 71, described later, is positioned at a height corresponding to the connection portion CP of the external electrodes 51, 52, and 53. Therefore, when wires 41, 42, and 43 are introduced from the outside of the housing body 21 toward the connection portion CP of the external electrodes 51, 52, and 53, by introducing the wires 41, 42, and 43 along a generally horizontal direction, the wires 41, 42, and 43 can be positioned at the connection portion CP of the external electrodes 51, 52, and 53. Furthermore, in this embodiment, as described above, the heights (positions in the height direction H) of the connection portions CP of the external electrodes 51, 52, and 53 are approximately the same, therefore the first guide portions 71 for each wire 41, 42, and 43 are positioned at approximately the same height. However, when the connection points CP of each of the external electrodes 51, 52, and 53 are positioned at different heights, the first guide 71 can be positioned at a height corresponding to the connection points CP of each external electrode 51, 52, and 53, or it can be tilted relative to the horizontal direction from the outside of the housing body 21 toward the connection points CP of each external electrode 51, 52, and 53.

[0067] In this embodiment, such as Figure 5 As shown, the second guide portion 72 is positioned at a height corresponding to the connection points CP of the external electrodes 51, 52, and 53 and the electrode structure 3. More specifically, the bottom surface of the second guide portion 72, described later, is positioned at a height corresponding to the connection points CP of the external electrodes 51, 52, and 53 and the electrode structure 3. Therefore, when wires 41, 42, and 43 are introduced from the connection points CP of the external electrodes 51, 52, and 53 toward the electrode structure 3, by introducing the wires 41, 42, and 43 in a generally horizontal direction, the wires 41, 42, and 43 can be positioned in the electrode structure 3. Here, in this embodiment, the electrodes 31, 32, and 33 of the electrode structure 3 are stacked on top of each other along the height direction H, and therefore are located at different heights within the electrode structure 3. In this embodiment, as... Figure 5 As shown, the second guide portion 72 for each electrode 31, 32, and 33 is positioned at a height corresponding to the highest reaction electrode 31 among the electrodes 31, 32, and 33. Therefore, regardless of which electrode 31, 32, or 33 uses wiring wires 41, 42, and 43, the wires 41, 42, and 43 can be introduced in a generally horizontal direction in the same way. However, the second guide portion 72 can also be, for example, as follows: Figure 6As shown, the second guide 72 is positioned at a height corresponding to each electrode 31, 32, 33 according to its position in the height direction H. More specifically, the bottom surface of the second guide 72 can also be positioned at a height corresponding to the surface of each electrode 31, 32, 33 according to its position in the height direction H. Therefore, due to the height difference between the connection point CP of each external electrode 51, 52, 53 and each electrode 31, 32, 33, the bending degree of the wires 41, 42, 43 is reduced, thereby reducing the load on the wires 41, 42, 43. Alternatively, for the same purpose, the second guide 72 can also be positioned as follows: Figure 7 As shown, the height difference between the connection points CP of each external electrode 51, 52, 53 and each electrode 31, 32, 33 is correspondingly inclined. More specifically, the bottom surface of the second guide 72 is inclined correspondingly to the height difference between the connection points CP of each external electrode 51, 52, 53 and each electrode 31, 32, 33.

[0068] In this embodiment, such as Figure 3 and Figure 4As shown, the housing body 21 has a wall portion W, which is formed around the horizontal direction of the connection portion CP of the external electrodes 51, 52, and 53. A first guide portion 71 is formed by the peripheral wall of a first recess WR1, which is located on the side of the wall portion W opposite to the electrode structure 3 in the guide path of the wires 41, 42, and 43. A second guide portion 72 is formed by the peripheral wall of a second recess WR2, which is located on one side of the wall portion W of the electrode structure 3 in the guide path of the wires 41, 42, and 43. The first and second recesses WR1 and WR2 respectively penetrate the wall portion W along the guide path of the wires 41, 42, and 43, and are formed by a bottom surface separated from the lower end in the height direction H and side surfaces separated from the two sides in the horizontal direction perpendicular to the extension direction of the guide path of the wires 41, 42, and 43, and open at the upper end in the height direction H. The bottom and side surfaces of each of the first and second recesses WR1 and WR2 are defined to form the peripheral walls of the first and second recesses WR1 and WR2, serving as guide surfaces for the conductors 41, 42, and 43 to abut. In this embodiment, the bottom and side surfaces of each of the first and second recesses WR1 and WR2 are formed approximately parallel to the extension direction of the guide path of the conductors 41, 42, and 43. The first and second recesses WR1 and WR2 are formed such that the spacing between the side surfaces facing each of the first and second recesses WR1 and WR2 is at least larger than the outer diameter of the conductors 41, 42, and 43, and their shapes are not particularly limited. In the illustrated example, each of the first and second recesses WR1 and WR2 is formed in a generally funnel shape such that the spacing between the side surfaces is constant on the lower side in the height direction H, and the opening towards the upper end increases on the upper side in the height direction H. Therefore, it is also easy to insert wires 41, 42, 43 into the first and second guides 71, 72 from the upper side of the height direction H of the housing body 21, and it is easy to arrange wires 41, 42, 43 between the connection part CP of the electrode structure 3 and the external electrodes 51, 52, 53.

[0069] In this embodiment, such as Figure 3 and Figure 4 As shown, the housing body 21 has a retaining structure 8 for each of the external electrodes 51, 52, and 53. This retaining structure 8 can retain a predetermined amount of protective agent PA (see reference) in a manner that covers the connection points CP of the external electrodes 51, 52, and 53. Figure 11 and Figure 12By providing such a retaining structure 8, the connection points CP can be protected by the protective agent PA, thereby inhibiting the electrolyte 6 from corroding the connection points CP. Furthermore, the retaining structure 8 can hold a predetermined amount of protective agent PA, thus facilitating the management of the amount of protective agent PA applied to the connection points CP and promoting the automation of the gas sensor 1 manufacturing process. Additionally, the retaining structure 8 is provided corresponding to the connection points CP of the external electrodes 51, 52, and 53, which are located at a height corresponding to the electrode structure 3. Therefore, the retaining structure 8 is located at a height corresponding to the electrode structure 3 and the connection points CP of the external electrodes 51, 52, and 53, or approximately above or below this height. Thus, after configuring the electrodes 31, 32, and 33 of the electrode structure 3 and placing the wires 41, 42, and 43 between the electrodes 31, 32, and 33 and the connection points CP of the external electrodes 51, 52, and 53, the protective agent PA can be applied to the connection points CP of the external electrodes 51, 52, and 53. Therefore, unlike existing technologies that require applying a protective agent to the connection points of external electrodes before configuring electrodes and wiring wires, there is no need to wait for the protective agent to dry or cure during the manufacturing process. Furthermore, unlike existing technologies where the connection points of external electrodes are located on the bottom surface of the housing body, the application device for applying the protective agent PA does not need to be inserted deep into the housing body 21 below the location where the electrode structure 3 is located. The retaining structure 8 can be easily accessed, thus facilitating the application of the protective agent PA.

[0070] The retaining structure 8 only needs to retain a predetermined amount of protective agent PA in a manner that covers the connection points CP of the external electrodes 51, 52, and 53; its structure is not particularly limited. In this embodiment, as... Figure 3 and Figure 4 As shown, the retaining structure 8 includes a wall portion W formed around the horizontal circumference of the connection portions CP of the external electrodes 51, 52, and 53. The wall portion W is disposed around the entire circumference of the connection portions CP in the horizontal direction and extends above the connection portions CP in the height direction H. The retaining structure 8 can retain a predetermined amount of protective agent PA by means of the wall portion W formed around the horizontal circumference of the connection portions CP, thereby protecting the connection portions CP with a predetermined amount of protective agent PA. In this embodiment, the retaining structure 8 includes the wall portion W formed around the connection portions CP and a bottom B that closes the space enclosed by the wall portion W at its lower end; the retaining structure 8 is formed as a bottomed cylindrical shape. External electrodes 51, 52, and 53 protrude from the surface of the bottom B of the retaining structure 8, and connection portions CP connected to each wire 41, 42, and 43 are formed at the upper ends of the protruding external electrodes 51, 52, and 53.

[0071] In this embodiment, such as Figure 3 and Figure 4As shown, the retaining structure 8 includes a guide 7 that guides wires 41, 42, and 43 along an introduction path that extends from the outside of the housing body 21 through the connection points CP of the external electrodes 51, 52, and 53 toward the electrode structure 3. By including the guide 7 in the retaining structure 8, it is not necessary to reconfigure the wires 41, 42, and 43. The wires 41, 42, and 43 can be guided from the outside of the housing body 21 to the electrode structure 3 at approximately the same position, positioned between the electrode structure 3 and the connection points CP of the external electrodes 51, 52, and 53, connected to the connection points CP of the external electrodes 51, 52, and 53, and the retaining structure 8 can be filled with a protective agent PA.

[0072] The protective agent PA inhibits the contact between the electrolyte 6 and the connection points CP of the external electrodes 51, 52, and 53 by covering them, thereby inhibiting the electrolyte 6 from corroding the connection points CP. The protective agent PA is not particularly limited as long as it can protect the connection points CP of the external electrodes 51, 52, and 53 from corrosion by the electrolyte 6. However, from the perspective of easy filling into the retaining structure 8, a thermosetting resin that is uncured before filling and can be cured after filling is preferred. From the perspective of preventing the protective agent PA from overflowing from the retaining structure 8, a thermosetting resin with a specified or higher viscosity in the uncured state is more preferred, such as an epoxy resin adhesive.

[0073] Next, refer to all the attached diagrams, especially... Figures 8-12 The manufacturing method of the gas sensor 1 according to this embodiment will be described. However, the following description is only an example, and the gas sensor and the manufacturing method of the gas sensor of the present invention are not limited to the following example. Furthermore, some steps are described sequentially below, but these steps can be performed simultaneously or in different orders. In addition, in Figures 8-12 In order to make it easier to understand the configuration of electrodes 31, 32, and 33 of electrode structure 3, the illustrations of other constituent elements of electrode structure 3 are omitted.

[0074] like Figure 8 As shown, the manufacturing method of the gas sensor 1 in this embodiment includes the step of providing a housing body 21. External electrodes 51, 52, and 53 are fixed to the housing body 21. In this embodiment, the housing body 21 and the external electrodes 51, 52, and 53 are integrally formed, thus eliminating the need for assembling the housing body 21 and the external electrodes 51, 52, and 53 separately. Furthermore, an outflow-side buffer membrane OB and an outflow-side permeable sheet OS (see reference) are laminated on the housing body 21. Figure 1 and Figure 2 The outflow-side permeable sheet OS is fixed to the housing body 21 by heat fusion.

[0075] like Figure 8 As shown, as the next step, the manufacturing method includes the step of setting the electrode structure 3 on the housing body 21. In this step, firstly, the counter electrode 32 of the electrode structure 3 is set on the housing body 21. In this embodiment, the counter electrode 32 is stacked on the surface of the outflow-side permeable sheet OS. The reference electrode 33 and the reaction electrode 31 of the electrode structure 3 are stacked on top of the counter electrode 32 either in parallel with subsequent steps or after subsequent steps. However, the electrodes 31, 32, and 33 may also be stacked in a different order.

[0076] like Figure 8 As shown, as the next step, the manufacturing method includes introducing wires 41, 42, and 43 along an introduction path that extends from the outside of the housing body 21 through the connection points CP of the external electrodes 51, 52, and 53 toward the electrode structure 3. Figure 8 In this example, the counter electrode wire 42 is introduced from the outside of the housing body 21 via the connection portion CP of the external counter electrode 52 toward the electrode structure 3. By introducing the counter electrode wire 42 from the outside of the housing body 21 via the connection portion CP toward the electrode structure 3, the introduction of the counter electrode wire 42 from the outside of the housing body 21 and the subsequent placement of the counter electrode wire 42 between the electrode structure 3 and the connection portion CP can be performed in a series of steps. In this embodiment, since the connection portion CP is located at a height corresponding to the electrode structure 3, the counter electrode wire 42 can be introduced in a generally horizontal direction, and the counter electrode wire 42 can be easily introduced by mechanical operation. In addition, in this embodiment, since a guide portion 7 for guiding the counter electrode wire 42 is provided, the wiring of the counter electrode wire 42 can be performed easily and accurately. Alternatively, instead of introducing the counter electrode wire 42 along the above-described introduction path via the connection portion CP into the electrode structure 3, the counter electrode wire 42 can be introduced, for example, from the upper side of the housing body 21 toward both the connection portion CP and the electrode structure 3.

[0077] like Figure 9 As shown, as a next step, the manufacturing method includes the step of placing wires 41, 42, 43 between the surfaces of electrodes 31, 32, 33 and the connection points CP of external electrodes 51, 52, 53. Figure 9 In this example, the counter electrode wire 42 is positioned between the surface of the counter electrode 32 and the connection point CP of the external counter electrode 52. Furthermore, in this process, the counter electrode wire 42 only needs to be located at least above the surface of the counter electrode 32 in the height direction H, as shown below. Figure 9The electrode may be in contact with the surface of the counter electrode 32, or it may be slightly raised from the surface of the counter electrode 32. In this embodiment, this process is performed before connecting the counter electrode wire 42 to the counter electrode 32 and the external electrode 52 for the counter electrode.

[0078] like Figure 9 As shown, as the next step, the manufacturing process includes connecting the wires 41, 42, and 43 to the external electrodes 51, 52, and 53 at the connection points CP of the external electrodes 51, 52, and 53, while the wires 41, 42, and 43 are arranged on the surfaces of the electrodes 31, 32, and 33. Furthermore, if the wires 41, 42, and 43 are wires of a predetermined length or longer, such as wires wound on a spool, then after connecting the wires 41, 42, and 43 to the external electrodes 51, 52, and 53, a step may be included where, while the wires 41, 42, and 43 are connected to the external electrodes 51, 52, and 53 and arranged on the surfaces of the electrodes 31, 32, and 33, the wires 41, 42, and 43 are cut at a predetermined position (e.g., outside the first guide portion 71, between the first guide portion 71 and the connection point CP, etc.). Figure 9 In this example, the counter electrode wire 42, while disposed on the surface of the counter electrode 32, is connected to the external counter electrode 52 at the connection point CP. The connection between the counter electrode wire 42 and the external counter electrode 52 is achieved through welding or the like. In the prior art, wiring requires bending the wire so that the other end is disposed on the electrode after connecting one end to the external electrode, making wiring difficult. However, in this embodiment, since the counter electrode wire 42 is connected to the external counter electrode 52 while disposed on the surface of the counter electrode 32, such complex wiring is unnecessary. Furthermore, in this process, the counter electrode wire 42 only needs to be positioned at least above the surface of the counter electrode 32 in the height direction H, as shown in the example. Figure 9 As shown, it is in contact with the surface of the counter electrode 32, and can also float slightly above the surface of the counter electrode 32. For example... Figure 10 As shown, in the next process, other components are stacked on top of the counter electrode 32, utilizing the housing cover 22 (see reference). Figure 1 and Figure 2 The housing body 21 is closed, so that the electrode wire 42 is pressed onto the surface of the electrode 32 and connected to the electrode 32 in such a way that it extends along the surface of the electrode 32.

[0079] Next, in this embodiment, an electrolyte holding member 35 for the counter electrode, an electrolyte holding member 37 for electrolyte supply, and a support sheet 39 (see reference) are sequentially stacked above the counter electrode 32. Figure 1 and Figure 2After that, such as Figure 10 As shown, a reference electrode 33 is stacked. Furthermore, the reference electrode wire 43 is introduced along a lead-in path in the same manner as the counter electrode wire 42, this lead-in path extending from the outside of the housing body 21 through the connection portion CP of the external reference electrode 53 (see reference). Figure 3 and Figure 4 The reference electrode wire 43 is positioned between the surface of the reference electrode 33 and the connection point CP of the external reference electrode 53, and is connected to the external reference electrode 53 at the connection point CP while still on the surface of the reference electrode 33. The connection between the reference electrode wire 43, the external reference electrode 53, and the reference electrode 33 is performed in the same manner as the counter electrode wire 42.

[0080] Next, in this embodiment, the reference electrode electrolyte holding member 36, the support sheet 38, and the reaction electrode electrolyte holding member 34 (see reference) are sequentially stacked above the reference electrode 33. Figure 1 and Figure 2 Then, as Figure 11 As shown, the reaction electrode wire 41 is introduced along an introduction path in the same manner as the counter electrode wire 42 and the reference electrode wire 43. This introduction path extends from the outside of the housing body 21, through the connection portion CP of the external electrode 51 of the reaction electrode, toward the electrode structure 3. The reaction electrode wire 41 is positioned on the reaction electrode 31 (see reference 31) which is subsequently positioned. Figure 12 After the imaginary surface of the reaction electrode 31 is positioned between the connection point CP of the external electrode 51 and the reaction electrode 31, the external electrode 51 is connected at the connection point CP to the external electrode 51. In this embodiment, the reaction electrode wire 41 is positioned on the imaginary surface of the reaction electrode 31 after the reaction electrode wire 41 is positioned. However, the reaction electrode wire 41 may also be positioned on the surface of the actual reaction electrode 31 after the reaction electrode 31 is positioned. The connection between the reaction electrode wire 41 and the external electrode 51 is performed in the same manner as the counter electrode wire 42 and the reference electrode wire 43.

[0081] like Figure 11As shown, as a subsequent manufacturing process, the manufacturing process may also include supplying a predetermined amount of protective agent PA to the retaining structure 8 in such a way that the connection points CP of the external electrodes 51, 52, and 53 are covered with protective agent PA, thereby suppressing corrosion by the electrolyte 6. The retaining structure 8 is configured to retain a predetermined amount of protective agent PA, thus facilitating the management of the amount of protective agent PA supplied.

[0082] Next, as Figure 12 As shown, the reaction electrode 31 is stacked on the reaction electrode electrolyte holding component 34 (see reference). Figure 1 and Figure 2 The reaction electrode 31 is connected to the reaction electrode 31 by extending along the surface of the reaction electrode 31. In this embodiment, the reaction electrode 31 is fixed to the housing cover 22 by means of a breathable sheet 31b, thereby fixing the reaction electrode 31 to the housing cover 22 through the breathable sheet 31b. Therefore, by using the housing cover 22 to close the housing body 21, the reaction electrode 31 is stacked on the reaction electrode electrolyte holding member 34 and the reaction electrode wire 41.

[0083] The housing cover 22 is fixed to the housing body 21 using known bonding methods such as ultrasonic welding and adhesives. Finally, electrolyte 6 is supplied to the electrolyte storage space CS formed inside the housing 2 by the housing cover 22 being fixed to the housing body 21 (see reference). Figure 2 ).

[0084] Next, use Figures 13-16 The second and third embodiments of the gas sensor 1, which are variations of the gas sensor 1 of the first embodiment described above, will be described. The main difference between the gas sensor 1 of the second and third embodiments and the gas sensor 1 of the first embodiment is that the electrodes of the electrode structure 3 include at least two reaction electrodes for detecting different target gases. Correspondingly, the wire 4 and the external electrode 5 each include at least two wires for reaction electrodes and at least two external electrodes for reaction electrodes. Hereinafter, descriptions of common aspects with the gas sensor 1 of the first embodiment will be omitted, and descriptions will focus on the differences. Furthermore, the same reference numerals will be used to describe components that have the same function as the components of the gas sensor 1 of the first embodiment. All aspects described for the gas sensor 1 of the first embodiment can be applied to the gas sensor 1 of the second and third embodiments, provided that the objective of the invention can be achieved. Furthermore, the effects obtained by the structure described in the gas sensor 1 of the first embodiment can also be obtained by the gas sensor 1 of the second and third embodiments if it possesses that structure.

[0085] Second Implementation Method like Figure 13 and Figure 14 As shown, in the gas sensor 1 of the second embodiment, the electrode structure 3 includes two reaction electrodes 31, 311 for detecting different target gases, a counter electrode 32, and a reference electrode 33. In this embodiment, a counter electrode 32 and a reference electrode 33 are used together for the two reaction electrodes 31, 311. However, the electrode structure 3 may also include two counter electrodes corresponding to each of the two reaction electrodes 31, 311. In this case, the two counter electrodes 32 can be formed, for example, by forming two electrode materials (e.g., approximately semi-circular) separated from each other by a slit-like spacer on a breathable sheet (e.g., generally circular), or they can be formed separately from each other. In this way, when the electrode structure 3 includes five electrodes in total—two reaction electrodes, two counter electrodes, and one reference electrode—the sensor 1 can also be formed using the housing 2 of the third embodiment, which also includes five electrodes in total, as described later. The gas sensor 1 can detect a first target gas, such as oxygen, through one of the two reaction electrodes 31, 311 (hereinafter also referred to as the "first reaction electrode 31"), and a second target gas, such as hydrogen sulfide or carbon monoxide, through the other reaction electrode 311 (hereinafter also referred to as the "second reaction electrode 311"). Furthermore, in this embodiment, the electrode structure 3 includes two reaction electrodes 31, 311. However, for the purpose of detecting different target gases, it is sufficient to include at least two reaction electrodes. It can also include three reaction electrodes, as shown in the gas sensor 1 of the third embodiment below, or more than three reaction electrodes. If it includes at least two reaction electrodes, the electrode structure 3 can also include at least two counter electrodes corresponding to each of the at least two reaction electrodes.

[0086] like Figure 13As shown, the first reaction electrode 31 and the second reaction electrode 311 are arranged in a manner that they do not overlap when viewed from the height direction H. More specifically, the first reaction electrode 31 is stacked with the counter electrode 32 and the reference electrode 33 in the height direction H, and the second reaction electrode 311 is arranged in a position separate from the first reaction electrode 31, the counter electrode 32, and the reference electrode 33 in a direction perpendicular to the height direction H (horizontal direction). Thus, gas can be supplied to each reaction electrode 31, 311 independently from the outside. Furthermore, when the electrode structure includes three or more reaction electrodes, the three or more reaction electrodes are arranged in a position separate from each other in a direction perpendicular to the height direction H (horizontal direction). The positions of the two reaction electrodes 31, 311 relative to each other in the height direction H are not particularly limited, but in this embodiment, the first and second reaction electrodes 31, 311 are fixed to the upper wall of the housing 22, and the second reaction electrode 311 is arranged at a height corresponding to the first reaction electrode 31. Furthermore, when the electrode structure includes three or more reaction electrodes, the three or more reaction electrodes are arranged at corresponding heights. In this embodiment, the structure of the first reaction electrode 31 and the second reaction electrode 311 is the same as that of the reaction electrode 31 described for the gas sensor 1 of the first embodiment, and the first reaction electrode 31 and the second reaction electrode 311 have the same structure as each other. However, the first reaction electrode 31 and the second reaction electrode 311 may also have a different structure than the reaction electrode 31 in the first embodiment, and the first reaction electrode 31 and the second reaction electrode 311 may also have different structures as each other.

[0087] In the electrode structure 3, which includes two reaction electrodes 31, 311, as follows Figure 13As shown, the electrolyte holding member 34 for the reaction electrodes, which is stacked on top of the two reaction electrodes 31 and 311, is formed in a shape and size that contacts the surfaces of both reaction electrodes 31 and 311. Therefore, electrolyte 6 can be supplied to both reaction electrodes 31 and 311 through one electrolyte holding member 34. In this embodiment, the electrolyte holding member 34 for the reaction electrodes is formed in a sheet shape with a shape and size matching the first electrode structure support space SS and the second electrode structure support space SS1 of the housing body 21, described later. Similarly, the electrolyte holding member 36 for the reference electrode is also formed in a sheet shape with approximately the same shape and size as the electrolyte holding member 34 for the reaction electrodes. In this embodiment, the electrolyte holding member 35 for the counter electrode is formed in a generally circular sheet shape that matches the first electrode structure support space SS, but it can also be formed in a sheet shape with approximately the same shape and size as the electrolyte holding member 34 for the reaction electrodes. In addition, the support sheets 38 and 39, which are arbitrarily stacked within the electrode structure 3, have a shape that is approximately the same as that of the electrolyte holding member 34 for the reaction electrode and the electrolyte holding member 36 for the reference electrode, but are formed to be smaller in size than the electrolyte holding member 34 for the reaction electrode and the electrolyte holding member 36 for the reference electrode, so as to avoid hindering the contact between the electrolyte holding members.

[0088] like Figure 13 As shown, the electrolyte supply and holding member 37, which is stacked within the electrode structure 3, has a sheet-like main body 37a and two sheet-like extensions 37b, 37b protruding from the main body 37a in opposite directions along a substantially straight line. The main body 37a is matched with the first electrode structure support space SS on the electrode structure support 212 (described later), and also matches the main body groove 2121a of the electrode structure support 212 (see reference). Figure 14 The main body 37a is formed in a matching manner with the first reaction electrode 31, the counter electrode 32, and the reference electrode 33 (and electrolyte holding components for each electrode) in the first electrode structure support space SS. Additionally, the two extensions 37b, 37b are respectively connected to the extension groove 2121b of the electrode structure support 212 (see below). Figure 14 The two extensions 37b, 37b extend in opposite directions relative to the electrode structure support 212 of the housing body 21, and bend at the outer edge of the electrode structure support 212, and are positioned facing each other within the electrolyte storage space CS (see also...). Figure 2 A portion of one of the two extensions 37b is partially stacked with the second reaction electrode 311 (and the electrolyte holding member 34 for the reaction electrode and the electrolyte holding member 36 for the reference electrode) in the second electrode structure support space SS1.

[0089] The gas sensor 1 of this embodiment has two reaction electrodes 31, 311, and correspondingly, as shown below... Figure 13 and Figure 14 As shown, the gas sensor 1 includes two reaction electrode wires 41, 411 connected to each of the two reaction electrodes 31, 311, and two external reaction electrode electrodes 51, 511 connected to each of the two reaction electrode wires 41, 411. That is, in the gas sensor 1 of this embodiment, the wires 4 include two reaction electrode wires 41, 411, a counter electrode wire 42 connected to the counter electrode 32, and a reference electrode wire 43 connected to the reference electrode 33. The external electrodes 5 include two reaction electrode external electrodes 51, 511, a counter electrode external electrode 52 connected to the counter electrode wire 42, and a reference electrode external electrode 53 connected to the reference electrode wire 43. The two reaction electrode external electrodes 51, 511 are arranged such that the connection points CP of the two reaction electrode external electrodes 51, 511 are located at a height corresponding to the two reaction electrodes 31, 311. Therefore, when connecting the two reaction electrodes 31, 311 and the two external reaction electrodes 51, 511 using the two reaction electrode wires 41, 411 respectively, wiring can be performed along both sides of the two reaction electrode wires 41, 411 in a generally horizontal direction without significant bending. This allows for easy wiring of the two reaction electrode wires 41, 411, and facilitates the manufacture of the gas sensor 1. Furthermore, when the electrode structure includes three or more reaction electrodes, three or more reaction electrode wires and three or more reaction electrode external electrodes are provided corresponding to each of the three or more reaction electrodes. In this case, the three or more reaction electrode external electrodes are arranged such that the connection points of the three or more reaction electrode external electrodes are located at a height corresponding to the three or more reaction electrodes. However, unlike the above description, the reaction electrode external electrodes may also be arranged such that the connection points of the reaction electrode external electrodes are located at a different height from the reaction electrodes.

[0090] In the gas sensor 1 of this embodiment, the housing 2 has a different structure from that of the gas sensor 1 of the first embodiment in order to additionally house the second reaction electrode 311, the wire 411 for the second reaction electrode, and the external electrode 511 for the second reaction electrode, based on the gas sensor 1 of the first embodiment. For example... Figure 13 and Figure 14As shown, the housing body 21 of the housing 2 in this embodiment includes: two external electrode supports 214, 214 for supporting one external electrode (in this embodiment, each of the external electrode 51 for the first reaction electrode and the external electrode 53 for the reference electrode), and one external electrode support 214 for supporting two external electrodes (in this embodiment, the external electrode 511 for the second reaction electrode and the external electrode 52 for the counter electrode). Each of the external electrode supports 214, 214 for supporting one external electrode 51, 53 is provided with a guide portion 7 and a retaining structure portion 8. The external electrode support 214 for supporting two external electrodes 511, 52 is provided with two guide portions 7, 7 and two retaining structures 8, 8. A partition wall W1 is provided between the two retaining structures 8, 8, thereby limiting the amount of protective agent PA used for the connection points CP of each external electrode 511, 52 to a predetermined amount. The guide portion 7 may also differ from the illustrated example and have the same structure as the guide portion 7 of the gas sensor 1 in the first embodiment. Furthermore, the number, shape, and configuration of the external electrode support, guide, and retaining structure can be appropriately modified according to the number, shape, and configuration of the reaction electrode, counter electrode, reference electrode, and external electrode.

[0091] In this embodiment, such as Figure 13 and Figure 14 As shown, a first electrode structure support space SS and a second electrode structure support space SS1 are formed on the surface of the electrode structure support portion 212 of the housing body 21. The first electrode structure support space SS is surrounded by three external electrode supports 214 near the center of the electrode structure support portion 212 in the horizontal direction. The second electrode structure support space SS1 is located between two adjacent external electrode supports 214, 214 along the periphery of the first electrode structure support space SS. The first electrode structure support space SS supports the first reaction electrode 31, the counter electrode 32, and the reference electrode 33 (as well as electrolyte holding members for each electrode). The second electrode structure support space SS1 supports the second reaction electrode 311 (as well as the electrolyte holding member 34 for the reaction electrode and the electrolyte holding member 36 for the reference electrode). Furthermore, in this embodiment, the first electrode structure support space SS is formed with the same shape and size as the electrode structure support space SS described for the gas sensor 1 of the first embodiment, but it may also be formed with a different shape and size than the electrode structure support space SS in the first embodiment.

[0092] like Figure 14As shown, a groove 2121 is formed in the electrode structure support portion 212 of the housing body 21. The groove 2121 is equipped with an outflow-side permeable sheet OS and an electrolyte supply holding member 37. The groove 2121 is shaped and sized to allow the outflow-side permeable sheet OS and the electrolyte supply holding member 37 to be inserted. The groove 2121 has a main groove 2121a into which the main body portion OS1 of the outflow-side permeable sheet OS and the main body portion 37a of the electrolyte supply holding member 37 can be inserted, and two extension grooves 2121b, 2121b into which the extension portion OS2 of the outflow-side permeable sheet OS and the extension portion 37b of the electrolyte supply holding member 37 can be inserted. The main groove 2121a is disposed below the first electrode structure support space SS, and one of the two extension grooves 2121b is disposed below a portion of the second electrode structure support space SS1. The second reaction electrode 311, supported in the second electrode structure support space SS1, is arranged to span the edge of the extension groove 2121b in a direction perpendicular to the extension direction of the extension groove 2121b.

[0093] like Figure 13 As shown, the outflow-side permeable sheet OS disposed in the groove 2121 of the electrode structure support 212 has a sheet-like main body OS1 and two sheet-like extensions OS2, OS2 protruding outward from the main body OS1 in opposite directions along approximately the same straight line. The two extensions OS2, OS2 extend along the extension groove 2121b of the groove 2121 in opposite directions relative to the electrode structure support 212 of the housing body 21, and bend at the outer edge of the electrode structure support 212, and are disposed in opposite positions within the electrolyte receiving space CS (see also...). Figure 2For example, if the gas sensor 1 is tilted towards one of the two extensions OS2, OS2, then one extension OS2 within the electrolyte storage space CS will be completely immersed in the electrolyte 6, making it difficult for gas within the electrolyte storage space CS to be discharged to the outside of the housing 2 through one extension OS2. However, even so, the other extension OS2 of the two extensions OS2 is at least partially (near the boundary between the electrode structure support 212 and the electrolyte storage space CS) not immersed in the electrolyte 6, so gas within the electrolyte storage space CS can be discharged to the outside of the housing 2 through the other extension OS2. In the gas sensor 1 of this embodiment, by providing an outflow-side permeable sheet OS having two extensions OS2 extending in opposite directions and in a substantially straight line, even if the gas sensor 1 is tilted, gas within the electrolyte storage space CS can be discharged to the outside of the housing 2, thus maintaining a constant pressure within the electrolyte storage space CS. To achieve this objective, in the gas sensor 1 of this embodiment, two external electrodes 51, 511 for reaction electrodes, an external electrode 52 for counter electrodes, and an external electrode 53 for reference electrodes are provided, so that an outflow-side permeable sheet OS with two extensions OS2, OS2 extending in opposite directions and in a substantially straight line can be provided.

[0094] As described above, the second reaction electrode 311 is arranged in the second electrode structure support space SS1 on the electrode structure support portion 2122 of the housing body 21 in such a way that it crosses the edge of the extension groove 2121b in a direction perpendicular to the extension direction of the extension groove 2121b (see reference). Figure 14 Therefore, a portion of the second reaction electrode 311 is disposed on the housing body 21 via the extension 37b of the electrolyte supply holding member 37, while the other portion of the second reaction electrode 311 is disposed on the housing body 21 without being disposed on the housing body 21 by the extension 37b of the electrolyte supply holding member 37. Thus, the second reaction electrode 311 is supplied with electrolyte 6 more reliably from the electrolyte supply holding member 37, and the second reaction electrode 311 is not pressed against the rigid housing body 21 by the electrolyte supply holding member 37, thereby ensuring more reliable contact with the wire 411 for the second reaction electrode. To achieve this, as... Figure 14 As shown, the second reaction electrode wire 411 is preferably arranged in contact with another part of the second reaction electrode 311, which is not provided on the housing body 21 by the electrolyte holding member 37 (extension 37b) for electrolyte supply.

[0095] like Figure 13As shown, within the housing cover 22 of the housing 2, two capillary components 22c, 22c are respectively provided at positions where two reaction electrodes 31, 311 are respectively located. Gas flows into the housing 2 through gas inlet holes h1 provided on the two capillary components 22c, 22c respectively, and is supplied to the two reaction electrodes 31, 311 corresponding to each capillary component 22c. By providing capillary components 22c according to the reaction electrodes 31, 311, the size of the gas inlet holes h1 can be changed according to the type of gas to be detected, for example, to obtain appropriate gas output characteristics. However, as long as holes for allowing gas to flow into the housing 2 are provided in the housing cover 22 corresponding to each reaction electrode 31, 311, only one capillary component may be provided corresponding to either of the two reaction electrodes 31, 311, or none may be provided.

[0096] The gas sensor 1 of the second embodiment can be manufactured using the same method as the gas sensor 1 described for the first embodiment.

[0097] Third Implementation Method In the gas sensor 1 of the third embodiment, as follows Figure 15 and Figure 16As shown, the electrode structure 3 includes three reaction electrodes 31, 311, and 312 for detecting different target gases, a counter electrode 32, and a reference electrode 33. In this embodiment, the counter electrode 32 and the reference electrode 33 are used together for the three reaction electrodes 31, 311, and 312. However, the electrode structure 3 may also include three counter electrodes corresponding to each of the three reaction electrodes 31, 311, and 312. In this case, the three counter electrodes can be formed, for example, by forming three electrode materials spaced apart from each other on a breathable sheet, or they can be formed separately from each other. The gas sensor 1 can detect a first target gas, such as oxygen, through the first reaction electrode 31 of the three reaction electrodes 31, 311, and 312; detect a second target gas, such as hydrogen sulfide, through the second reaction electrode 311 of the three reaction electrodes 31, 311, and 312; and detect a third target gas, such as carbon monoxide, through the third reaction electrode 312 of the three reaction electrodes 31, 311, and 312. Furthermore, the electrodes of electrode structure 3 may also include two counter electrodes for the three reaction electrodes 31, 311, and 312. The two counter electrodes can be used separately based on the reaction occurring on the counter electrode; for example, one of the two counter electrodes can be used in a reaction electrode for detecting a target gas (e.g., oxygen) undergoing an oxidation reaction on the counter electrode, and the other of the two counter electrodes can be used in a reaction electrode for detecting a target gas (e.g., hydrogen sulfide gas, carbon monoxide gas) undergoing a reduction reaction on the counter electrode. In this case, as described above, the two counter electrodes can be formed, for example, by forming two electrode materials (e.g., approximately semi-circular) on a permeable sheet (e.g., generally circular) separated from each other by a slit-like spacer, or they can be formed independently of each other. Similarly, when there are more than three reaction electrodes, the two counter electrodes can be used separately based on the oxidation and reduction reactions occurring on the counter electrode.

[0098] like Figure 15As shown, the first to third reaction electrodes 31, 311, and 312 are arranged so as not to overlap when viewed from the height direction H. More specifically, the first reaction electrode 31 is stacked with the counter electrode 32 and the reference electrode 33 in the height direction H, while the second and third reaction electrodes 311 and 312 are positioned separately from the first reaction electrode 31, the counter electrode 32, and the reference electrode 33 in a direction perpendicular to the height direction H (horizontal direction). The second and third reaction electrodes 311 and 312 are also positioned separately from each other in a direction perpendicular to the height direction H (horizontal direction). Thus, gas can be supplied to each reaction electrode 31, 311, and 312 independently from the outside. The positions of the three reaction electrodes 31, 311, and 312 relative to each other in the height direction H are not particularly limited, but in this embodiment, the first to third reaction electrodes 31, 311, and 312 are fixed to the upper wall of the housing 22, and the second and third reaction electrodes 311 and 312 are positioned at a height corresponding to the first reaction electrode 31. In this embodiment, the structures of the first to third reaction electrodes 31, 311, and 312 are the same as those of the reaction electrode 31 described for the gas sensor 1 of the first embodiment, and the first to third reaction electrodes 31, 311, and 312 have the same structure as each other. However, the first to third reaction electrodes 31, 311, and 312 may also have different structures than the reaction electrode 31 in the first embodiment, and the first to third reaction electrodes 31, 311, and 312 may also have different structures as each other.

[0099] In electrode structure 3, which includes three reaction electrodes 31, 311, and 312, as follows: Figure 15As shown, the electrolyte holding member 34 for the reaction electrodes, which is stacked on the three reaction electrodes 31, 311, and 312, is formed in a shape and size that contacts all surfaces of the three reaction electrodes 31, 311, and 312. Thus, electrolyte 6 can be supplied to all three reaction electrodes 31, 311, and 312 through one electrolyte holding member 34. In this embodiment, the electrolyte holding member 34 for the reaction electrodes is formed in a sheet shape with a shape and size matching the first electrode structure support space SS, the second electrode structure support space SS1, and the third electrode structure holding space SS2 of the housing body 21 (described later). Similarly, the electrolyte holding member 36 for the reference electrode is also formed in a sheet shape with approximately the same shape and size as the electrolyte holding member 34 for the reaction electrodes. In this embodiment, the electrolyte holding member 35 for the electrode is formed in a generally circular sheet shape that matches the first electrode structure support space SS, but it could also be formed in a sheet shape with approximately the same shape and size as the electrolyte holding member 34 for the reaction electrodes. In addition, the support sheets 38 and 39, which are arbitrarily stacked within the electrode structure 3, have a shape that is approximately the same as that of the electrolyte holding member 34 for the reaction electrode and the electrolyte holding member 36 for the reference electrode, but are formed to be smaller in size than the electrolyte holding member 34 for the reaction electrode and the electrolyte holding member 36 for the reference electrode, so as to avoid hindering the contact between the electrolyte holding members.

[0100] like Figure 15 As shown, the electrolyte supply and holding member 37, which is stacked within the electrode structure 3, has a sheet-like main body 37a and two sheet-like extensions 37b, 37b protruding from the main body 37a in opposite directions along a substantially straight line. The main body 37a is matched with the first electrode structure support space SS on the electrode structure support 212 (described later), and also matches the main body groove 2121a of the electrode structure support 212 (see reference). Figure 16 The main body 37a is formed in a matching manner with the first reaction electrode 31, the counter electrode 32, and the reference electrode 33 (and electrolyte holding components for each electrode) in the first electrode structure support space SS. Additionally, the two extensions 37b, 37b are respectively connected to the extension groove 2121b of the electrode structure support 212 (see below). Figure 16 The two extensions 37b, 37b extend in opposite directions relative to the electrode structure support 212 of the housing body 21, and bend at the outer edge of the electrode structure support 212, and are positioned facing each other within the electrolyte storage space CS (see also...). Figure 2A portion of each of the two extensions 37b, 37b is partially stacked with each of the second and third reaction electrodes 311, 312 (and the electrolyte holding member 34 for the reaction electrode and the electrolyte holding member 36 for the reference electrode) in each of the second and third electrode structure support spaces SS1, SS2.

[0101] The gas sensor 1 of this embodiment has three reaction electrodes 31, 311, and 312, corresponding to which, as shown... Figure 15 and Figure 16 As shown, the gas sensor 1 includes three reaction electrode wires 41, 411, 412 connected to each of the three reaction electrodes 31, 311, 312, and three external reaction electrode electrodes 51, 511, 512 connected to each of the three reaction electrode wires 41, 411, 412. That is, in the gas sensor 1 of this embodiment, the wires 4 include the three reaction electrode wires 41, 411, 412, a counter electrode wire 42 connected to the counter electrode 32, and a reference electrode wire 43 connected to the reference electrode 33. The external electrodes 5 include the three reaction electrode external electrodes 51, 511, 512, a counter electrode external electrode 52 connected to the counter electrode wire 42, and a reference electrode external electrode 53 connected to the reference electrode wire 43. The three reaction electrode external electrodes 51, 511, 512 are arranged such that the connection points CP of the three reaction electrode external electrodes 51, 511, 513 are located at heights corresponding to the three reaction electrodes 31, 311, 312. Therefore, when the three reaction electrodes 31, 311, 312 are connected to the three external reaction electrodes 51, 511, 512 using the three reaction electrode wires 41, 411, 412 respectively, the three reaction electrode wires 41, 411, 412 can be wired in a roughly horizontal direction without significant bending. Thus, the three reaction electrode wires 41, 411, 412 can be wired easily, and the gas sensor 1 can be easily manufactured.

[0102] In the gas sensor 1 of this embodiment, the housing 2 has a different structure from that of the gas sensor 1 of the first embodiment in order to accommodate the second and third reaction electrodes 311, 312, the wires 411, 412 for the second and third reaction electrodes, and the external electrodes 511, 512 for the second and third reaction electrodes, in addition to the structure of the gas sensor 1 of the first embodiment. For example Figure 15 and Figure 16As shown, the housing body 21 of the housing 2 in this embodiment includes: an external electrode support 214 for supporting three external electrodes (in this embodiment, an external electrode 51 for the first reaction electrode, an external electrode 52 for the counter electrode, and an external electrode 53 for the reference electrode), and an external electrode support 214 for supporting two external electrodes (in this embodiment, external electrodes 511 and 512 for the second and third reaction electrodes). The external electrode support 214 for supporting the three external electrodes 51, 52, and 53 is provided with three guide portions 7 and one holding structure portion 8, while the external electrode support 214 for supporting the two external electrodes 511 and 512 is provided with two guide portions 7 and one holding structure portion 8. The guide portions 7 may also differ from the illustrated example and have the same structure as the guide portion 7 of the gas sensor 1 in the first embodiment. Furthermore, the number, shape, and arrangement of the external electrode support portions, guide portions, and holding structure portions can be appropriately modified according to the number, shape, and arrangement of the reaction electrode, counter electrode, reference electrode, and external electrodes.

[0103] In this embodiment, such as Figure 15 and Figure 16 As shown, a first electrode structure support space SS, a second electrode structure support space SS1, and a third electrode structure support space SS2 are formed on the surface of the electrode structure support portion 212 of the housing body 21. The first electrode structure support space SS is surrounded by two external electrode supports 214, 214 near the center of the electrode structure support portion 212 in the horizontal direction. The second electrode structure support space SS1 and the third electrode structure support space SS2 are located between two adjacent external electrode supports 214, 214 along the periphery of the first electrode structure support space SS. The first electrode structure support space SS supports the first reaction electrode 31, the counter electrode 32, and the reference electrode 33 (and their respective electrolyte holding components). The second electrode structure support space SS1 supports the second reaction electrode 311 (and the reaction electrode electrolyte holding component 34 and the reference electrode electrolyte holding component 36). The third electrode structure support space SS2 supports the third reaction electrode 312 (and the reaction electrode electrolyte holding component 34 and the reference electrode electrolyte holding component 36). Furthermore, in this embodiment, the first electrode structure support space SS is formed with the same shape and size as the electrode structure support space SS described for the gas sensor 1 of the first embodiment, but it may also be formed with a different shape and size than the electrode structure support space SS in the first embodiment.

[0104] like Figure 16As shown, a groove 2121 is formed in the electrode structure support portion 212 of the housing body 21. The groove 2121 is equipped with an outflow-side permeable sheet OS and an electrolyte supply holding member 37. The groove 2121 is shaped and sized to allow the outflow-side permeable sheet OS and the electrolyte supply holding member 37 to be inserted. The groove 2121 has a main groove 2121a into which the main body portion OS1 of the outflow-side permeable sheet OS and the main body portion 37a of the electrolyte supply holding member 37 can be inserted, and two extension grooves 2121b, 2121b into which the extension portion OS2 of the outflow-side permeable sheet OS and the extension portion 37b of the electrolyte supply holding member 37 can be inserted. The main groove 2121a is disposed below the first electrode structure support space SS, and the two extension grooves 2121b, 2121b are respectively disposed below a portion of the second and third electrode structure support spaces SS1, SS2. The second and third reaction electrodes 311, 312 supported in the second and third electrode structure support spaces SS1, SS2 are respectively arranged such that they cross the edge of the extension groove 2121b in a direction perpendicular to the extension direction of the extension groove 2121b.

[0105] like Figure 15 As shown, the outflow-side permeable sheet OS disposed in the groove 2121 of the electrode structure support 212 has a sheet-like main body OS1 and two sheet-like extensions OS2, OS2 protruding outward from the main body OS1 in opposite directions along approximately the same straight line. The two extensions OS2, OS2 extend along the extension groove 2121b of the groove 2121 in opposite directions relative to the electrode structure support 212 of the housing body 21, and bend at the outer edge of the electrode structure support 212, and are disposed in opposite positions within the electrolyte receiving space CS (see also...). Figure 2For example, if the gas sensor 1 is tilted towards one of the two extensions OS2, OS2, then one extension OS2 within the electrolyte storage space CS will be completely immersed in the electrolyte 6, making it difficult for gas within the electrolyte storage space CS to be discharged to the outside of the housing 2 through one extension OS2. However, even so, the other extension OS2 of the two extensions OS2 is at least partially (near the boundary between the electrode structure support 212 and the electrolyte storage space CS) not immersed in the electrolyte 6, so gas within the electrolyte storage space CS can be discharged to the outside of the housing 2 through the other extension OS2. In the gas sensor 1 of this embodiment, by providing an outflow-side permeable sheet OS having two extensions OS2 extending in opposite directions and in a substantially straight line, even if the gas sensor 1 is tilted, gas within the electrolyte storage space CS can be discharged to the outside of the housing 2, thus maintaining a constant pressure within the electrolyte storage space CS. To achieve this objective, in the gas sensor 1 of this embodiment, three external electrodes 51, 511, and 512 for reaction electrodes, an external electrode 52 for counter electrodes, and an external electrode 53 for reference electrodes are provided, so that an outflow-side permeable sheet OS with two extensions OS2 extending in opposite directions and in a substantially straight line can be provided.

[0106] As described above, each of the second and third reaction electrodes 311, 312 is arranged in each of the second and third electrode structure support spaces SS1, SS2 on the electrode structure support portion 212 of the housing body 21 in such a way that it crosses the edge of the extension groove 2121b in a direction perpendicular to the extension direction of the extension groove 2121b (see reference). Figure 16 Therefore, a portion of each of the second and third reaction electrodes 311 and 312 is disposed on the housing body 21 via an extension 37b of the electrolyte supply holding member 37, while the other portion of each of the second and third reaction electrodes 311 and 312 is disposed on the housing body 21 without being disposed on the housing body 21 by the extension 37b of the electrolyte supply holding member 37. Thus, the second and third reaction electrodes 311 and 312 are supplied with electrolyte 6 more reliably from the electrolyte supply holding member 37, and the second and third reaction electrodes 311 and 312 are not pressed against the rigid housing body 21 by the electrolyte supply holding member 37, thereby more reliably ensuring contact with the wires 411 and 412 of the second and third reaction electrodes. To achieve this objective, as... Figure 16As shown, the wires 411 and 412 for the second and third reaction electrodes are preferably configured to be connected to another part of each of the second and third reaction electrodes 311 and 312, which are not provided on the housing body 21 by the electrolyte holding member 37 (extension 37b) for electrolyte supply.

[0107] like Figure 15 As shown, within the housing cover 22 of the housing 2, three capillary components 22c are respectively provided at the positions where three reaction electrodes 31, 311, and 312 are respectively located. Gas flows into the housing 2 through the gas inlet holes h1 provided on the three capillary components 22c respectively, and is supplied to the three reaction electrodes 31, 311, and 312 provided corresponding to each capillary component 22c. By providing capillary components 22c according to the reaction electrodes 31, 311, and 312, the size of the gas inlet holes h1 can be changed according to the type of gas to be detected, for example, to obtain appropriate gas output characteristics. However, as long as holes for gas to flow into the housing 2 are provided in the housing cover 22 corresponding to each reaction electrode 31, 311, and 312, only one capillary component can be provided corresponding to any one of the three reaction electrodes 31, 311, and 312, or two can be provided corresponding to any two, or none can be provided.

[0108] The gas sensor 1 of the third embodiment can be manufactured using the same method as the gas sensor 1 manufacturing method described for the gas sensor 1 of the first embodiment.

[0109] The constant-potential electrolytic gas sensor and its manufacturing method according to some embodiments of the present invention have been described above. However, the constant-potential electrolytic gas sensor and its manufacturing method of the present invention are not limited to the embodiments described above. The above embodiments mainly describe the invention having the following structure.

[0110] (1) A constant potential electrolytic gas sensor, comprising: The shell, which has a shell body; An electrode structure comprising at least two electrodes disposed on the housing body; At least two wires, the at least two wires extending along and connected to the surface of each of the at least two electrodes; and At least two external electrodes extend from the outside of the housing into the inside of the housing body, are disposed on the housing body, and are connected to each of the at least two wires. The at least two external electrodes are arranged such that the connection points of the external electrodes connected to the wires are located at a height corresponding to the electrode structure. The housing body has a guide portion that guides the wire along an introduction path that extends from the outside of the housing body through the connection portion of the external electrode toward the electrode structure.

[0111] (2) Based on the constant potential electrolytic gas sensor described in (1), the at least two external electrodes are configured such that the height of the connection parts of the at least two external electrodes is approximately the same as that of each other.

[0112] (3) Based on the constant potential electrolytic gas sensor described in (1) or (2), the guide portion includes: A first guide portion guides the wire from the outside of the housing body toward the connection portion of the external electrode; and The second guide portion guides the wire from the connection portion of the external electrode toward the electrode structure.

[0113] (4) Based on the constant potential electrolytic gas sensor described in (3), the housing body has a wall portion formed around the horizontal direction of the connection portion of the external electrode. The first guide portion is formed by the peripheral wall of the first recess of the wall portion located on the side opposite to the electrode structure in the guide path. The second guide portion is formed by the peripheral wall of the second recess of the wall portion disposed on one side of the electrode structure in the guide path.

[0114] (5) Based on the constant potential electrolytic gas sensor described in (3) or (4), the second guide portion is located at a height corresponding to each of the at least two electrodes. or, The second guide portion is inclined in accordance with the connection point of each of the at least two external electrodes and the height difference between each of the at least two external electrodes.

[0115] (6) Based on any one of (1) to (5) of the constant potential electrolytic gas sensor, the at least two electrodes include at least two reaction electrodes, a counter electrode, and a reference electrode for detecting different target gases. The at least two wires include at least two reaction electrode wires connected to each of the at least two reaction electrodes, a counter electrode wire connected to the counter electrode, and a reference electrode wire connected to the reference electrode. The at least two external electrodes include at least two external electrodes for reacting electrodes connected to each of the at least two conductors for reacting electrodes, an external electrode for counter electrodes connected to the conductors for counter electrodes, and an external electrode for reference electrodes connected to the conductors for reference electrodes. The first reactive electrode of the at least two reactive electrodes is stacked with the counter electrode and the reference electrode in the height direction. The other reaction electrodes of the at least two reaction electrodes are positioned at a height corresponding to the first reaction electrode, separated from the first reaction electrode, the counter electrode, and the reference electrode in a direction perpendicular to the height direction.

[0116] (7) Based on the constant potential electrolytic gas sensor described in (6), the at least two external electrodes for reaction electrodes are configured such that the connection portion of the at least two external electrodes for reaction electrodes is located at a height corresponding to the at least two reaction electrodes.

[0117] (8) A method for manufacturing a constant-potential electrolytic gas sensor, The constant potential electrolytic gas sensor includes: The shell, which has a shell body; An electrode structure comprising at least two electrodes disposed on the housing body; At least two wires, the at least two wires extending along and connected to the surface of each of the at least two electrodes; and At least two external electrodes extend from the outside of the housing into the inside of the housing body, are disposed on the housing body, and are connected to each of the at least two wires. The method includes: The process of introducing the wire along an introduction path from the outside of the housing body through the connection portion of the external electrode toward the electrode structure; The process of placing the wire between the surface of the electrode and the connection point of the external electrode; and The process of connecting the wire to the external electrode at the connection point of the external electrode while the wire is disposed on the surface of the electrode.

Claims

1. A constant-potential electrolysis gas sensor, comprising: The shell, which has a shell body; An electrode structure comprising at least two electrodes disposed on the housing body; At least two wires, the at least two wires extending along the surface of each of the at least two electrodes and connected to the surface of each of the at least two electrodes; as well as At least two external electrodes extend from the outside of the housing into the inside of the housing body, are disposed on the housing body, and are connected to each of the at least two wires. The at least two external electrodes are arranged such that the connection points of the external electrodes connected to the wires are located at a height corresponding to the electrode structure. The housing body has a guide portion that guides the wire along an insertion path, the insertion path extending from the outside of the housing body through the connection portion of the external electrode toward the electrode structure. The guide section includes: A first guide portion guides the wire from the outside of the housing body toward the connection portion of the external electrode; and The second guide portion guides the wire from the connection portion of the external electrode toward the electrode structure.

2. The constant-potential electrolytic gas sensor according to claim 1, wherein, The at least two external electrodes are configured such that the height of the connection points of the at least two external electrodes is consistent with that of each other.

3. The constant-potential electrolytic gas sensor according to claim 1 or 2, wherein, The housing body has a wall portion formed around the horizontal perimeter of the connection portion of the external electrode. The first guide portion is formed by the peripheral wall of the first recess of the wall portion located on the side opposite to the electrode structure in the guide path. The second guide portion is formed by the peripheral wall of the second recess of the wall portion disposed on one side of the electrode structure in the guide path.

4. The constant-potential electrolytic gas sensor according to claim 1 or 2, wherein, The second guide portion is located at a height corresponding to each of the at least two electrodes. or, The second guide portion is inclined in accordance with the connection point of each of the at least two external electrodes and the height difference between each of the at least two electrodes.

5. The constant-potential electrolytic gas sensor according to claim 1 or 2, wherein, The at least two electrodes include at least two reaction electrodes, a counter electrode, and a reference electrode for detecting different target gases. The at least two wires include at least two reaction electrode wires connected to each of the at least two reaction electrodes, a counter electrode wire connected to the counter electrode, and a reference electrode wire connected to the reference electrode. The at least two external electrodes include at least two external electrodes for reacting electrodes connected to each of the at least two conductors for reacting electrodes, an external electrode for counter electrodes connected to the conductors for counter electrodes, and an external electrode for reference electrodes connected to the conductors for reference electrodes. The first reactive electrode of the at least two reactive electrodes is stacked with the counter electrode and the reference electrode in the height direction. The other reaction electrodes of the at least two reaction electrodes are positioned at a height corresponding to the first reaction electrode, separated from the first reaction electrode, the counter electrode, and the reference electrode in a direction perpendicular to the height direction.

6. The constant-potential electrolytic gas sensor according to claim 5, wherein, The at least two external electrodes for the reaction electrodes are configured such that the connection points of the at least two external electrodes for the reaction electrodes are located at a height corresponding to the at least two reaction electrodes.

7. A method for manufacturing a constant-potential electrolytic gas sensor, The constant potential electrolytic gas sensor includes: The shell, which has a shell body; An electrode structure comprising at least two electrodes disposed on the housing body; At least two wires, the at least two wires extending along the surface of each of the at least two electrodes and connected to the surface of each of the at least two electrodes; as well as At least two external electrodes extend from the outside of the housing into the inside of the housing body, are disposed on the housing body, and are connected to each of the at least two wires. The housing body has a guide portion that guides the wire along an introduction path that extends from the outside of the housing body through the connection portion of the external electrode toward the electrode structure. The at least two external electrodes are configured such that the connection portion of the external electrode to which the wire is connected is located at a height corresponding to the electrode structure. The guide section includes: A first guide portion guides the wire from the outside of the housing body toward the connection portion of the external electrode; and A second guide portion guides the wire from the connection point of the external electrode toward the electrode structure. The method includes: The process of guiding the wire along an introduction path from the outside of the housing body through the connection portion of the external electrode toward the electrode structure via the guide portion; The process of placing the wire between the surface of the electrode and the connection point of the external electrode; and The process of connecting the wire to the external electrode at the connection point of the external electrode while the wire is disposed on the surface of the electrode.

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