WO2020039942A1 - ガスセンサ素子 - Google Patents

ガスセンサ素子 Download PDF

Info

Publication number
WO2020039942A1
WO2020039942A1 PCT/JP2019/031225 JP2019031225W WO2020039942A1 WO 2020039942 A1 WO2020039942 A1 WO 2020039942A1 JP 2019031225 W JP2019031225 W JP 2019031225W WO 2020039942 A1 WO2020039942 A1 WO 2020039942A1
Authority
WO
WIPO (PCT)
Prior art keywords
insulator
gas sensor
sensor element
gas
boundary
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/JP2019/031225
Other languages
English (en)
French (fr)
Japanese (ja)
Inventor
池田　正俊
翔太 萩野
伊藤　誠
大介 河合
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Denso Corp
Original Assignee
Denso Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Denso Corp filed Critical Denso Corp
Publication of WO2020039942A1 publication Critical patent/WO2020039942A1/ja
Priority to US17/181,212 priority Critical patent/US12031936B2/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
    • G01N27/403—Cells and electrode assemblies
    • G01N27/406—Cells and probes with solid electrolytes
    • G01N27/4067—Means for heating or controlling the temperature of the solid electrolyte
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
    • G01N27/403—Cells and electrode assemblies
    • G01N27/406—Cells and probes with solid electrolytes
    • G01N27/407—Cells and probes with solid electrolytes for investigating or analysing gases
    • G01N27/4071—Cells and probes with solid electrolytes for investigating or analysing gases using sensor elements of laminated structure
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B3/00—Ohmic-resistance heating
    • H05B3/02—Details
    • H05B3/03—Electrodes
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B3/00—Ohmic-resistance heating
    • H05B3/10—Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor
    • H05B3/18—Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor the conductor being embedded in an insulating material
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B3/00—Ohmic-resistance heating
    • H05B3/20—Heating elements having extended surface area substantially in a two-dimensional plane, e.g. plate-heater
    • H05B3/22—Heating elements having extended surface area substantially in a two-dimensional plane, e.g. plate-heater non-flexible
    • H05B3/28—Heating elements having extended surface area substantially in a two-dimensional plane, e.g. plate-heater non-flexible heating conductor embedded in insulating material
    • H05B3/286—Heating elements having extended surface area substantially in a two-dimensional plane, e.g. plate-heater non-flexible heating conductor embedded in insulating material the insulating material being an organic material, e.g. plastic
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
    • G01N27/403—Cells and electrode assemblies
    • G01N27/406—Cells and probes with solid electrolytes
    • G01N27/407—Cells and probes with solid electrolytes for investigating or analysing gases
    • G01N27/409—Oxygen concentration cells

Definitions

  • the present disclosure relates to a gas sensor element.
  • a gas sensor is disposed, for example, in an exhaust pipe of an internal combustion engine and is used to detect the concentration of a specific gas component such as the oxygen concentration of exhaust gas flowing through the exhaust pipe.
  • the gas sensor described in Patent Literature 1 includes an electrolyte layer having a holding plate having an arrangement hole penetratingly formed in a thickness direction and a solid electrolyte body arranged in the arrangement hole.
  • the thickness of the pair of surface alumina layers is relatively thin, and the strength of the pair of surface alumina layers is low. Therefore, there is room for improvement from the viewpoint of stably holding the solid electrolyte body in the arrangement hole.
  • the present disclosure is intended to provide a gas sensor element in which a solid electrolyte body is hard to fall out of an arrangement hole.
  • One aspect of the present disclosure is a holding plate including an arrangement hole formed through in the thickness direction, and an electrolyte layer including a solid electrolyte body having oxygen ion conductivity and arranged in the arrangement hole, A first insulator laminated on one surface of the electrolyte layer, A second insulator laminated on the other surface of the electrolyte layer, A measurement gas chamber into which the gas to be measured is introduced while being surrounded by the electrolyte layer and the first insulator, Having a reference gas chamber in which a reference gas is introduced while being surrounded by the electrolyte layer and the second insulator, At least a part of the boundary between the placement hole and the solid electrolyte body is sandwiched by a first sandwiching portion of the first insulator and a second sandwiching portion of the second insulator, The first sandwiching portion is formed at a position overlapping the boundary portion in the thickness direction, and is formed at least in an entire region where the measurement gas chamber in the thickness direction is arranged, The second sandwiching portion is
  • the boundary between the arrangement hole of the holding plate and the solid electrolyte body is sandwiched by the first sandwiching portion of the first insulator and the second sandwiching portion of the second insulator.
  • the first holding portion is formed at least in the entire region where the measurement gas chamber is arranged in the thickness direction of the holding plate.
  • the second holding portion is formed at least in the entire region where the reference gas chamber in the thickness direction is arranged. That is, at least a part of the boundary portion is sandwiched between the first sandwiching portion and the second sandwiching portion formed of a relatively rigid structure. Therefore, it is easy to secure the rigidity of the first holding portion and the second holding portion that hold at least a part of the boundary portion, and it is easy to stably hold the solid electrolyte body in the arrangement hole.
  • FIG. 1 is a cross-sectional view orthogonal to the longitudinal direction of the gas sensor element according to the first embodiment
  • FIG. 2 is a cross-sectional view orthogonal to the width direction of the gas sensor element according to the first embodiment
  • FIG. 3 is a sectional view taken along line III-III of FIG.
  • FIG. 4 is an exploded perspective view in which each layer of the gas sensor element according to the first embodiment is disassembled.
  • FIG. 5 is a partial cross-sectional view parallel to the axial direction of the gas sensor according to the first embodiment.
  • FIG. 6 is a cross-sectional view orthogonal to the width direction of the gas sensor element according to the second embodiment.
  • FIG. 7 is a sectional view taken along line VII-VII of FIG.
  • FIG. 8 is an exploded perspective view in which each layer of the gas sensor element according to the second embodiment is disassembled.
  • the gas sensor element 1 of the present embodiment has an electrolyte layer 2, a first insulator 3, a second insulator 4, a measurement gas chamber 5, and a reference gas chamber 6, as shown in FIGS.
  • the electrolyte layer 2 includes a holding plate 22 and a solid electrolyte body 21.
  • the holding plate 22 includes an arrangement hole 220 formed through the holding plate 22 in a thickness direction (hereinafter, referred to as a Z direction).
  • the solid electrolyte member 21 is arranged in the arrangement hole 220.
  • the solid electrolyte member 21 has oxygen ion conductivity.
  • the first insulator 3 is laminated on one surface of the electrolyte layer 2.
  • the second insulator 4 is laminated on the other surface of the electrolyte layer 2.
  • the measurement gas chamber 5 is surrounded by the electrolyte layer 2 and the first insulator 3. As shown in FIG. 2, the measured gas G is introduced into the measurement gas chamber 5.
  • the reference gas chamber 6 is surrounded by the electrolyte layer 2 and the second insulator 4.
  • the reference gas A is introduced into the reference gas chamber 6.
  • the boundary portion 23 between the arrangement hole 220 and the solid electrolyte member 21 is formed by the first holding portion 33 of the first insulator 3 and the second holding portion of the second insulator 4.
  • Portion 45 The first holding portion 33 is formed at a position overlapping the boundary portion 23 in the Z direction.
  • the first holding portion 33 is formed at least in the entire region where the measurement gas chamber 5 in the Z direction is arranged.
  • the second holding portion 45 is formed at a position overlapping the boundary portion 23 in the Z direction.
  • the second holding portion 45 is formed at least in the entire region where the reference gas chamber 6 is arranged in the thickness direction.
  • the gas sensor 10 including the gas sensor element 1 is arranged in an exhaust pipe (not shown) of an engine as an internal combustion engine.
  • the gas sensor 10 uses the exhaust gas passing through the exhaust pipe as the gas to be measured G, uses the atmosphere as the reference gas A, obtains the oxygen concentration of the gas to be measured G, and determines the A / F (air-fuel ratio) of the engine based on the oxygen concentration.
  • the gas sensor 10 can be an A / F sensor that quantitatively obtains the air-fuel ratio of the engine by using the limit current characteristic based on the diffusion control of the gas G to be measured.
  • the gas sensor element 1 is formed by laminating a first insulator 3, an electrolyte layer 2, and a second insulator 4 in a thickness direction and sintering them.
  • the lamination direction of the first insulator 3, the electrolyte layer 2, and the second insulator 4 is referred to as a Z direction.
  • the first insulator 3 side with respect to the electrolyte layer 2 in the Z direction is referred to as Z1 side
  • the opposite side, that is, the second insulator 4 side with respect to the electrolyte layer 2 is referred to as Z2 side.
  • the longitudinal direction of the gas sensor element 1 is called an X direction.
  • the side on which the gas to be measured G is introduced into the gas sensor element 1 is defined as the distal end, and the side on which the reference gas A is introduced is defined as the proximal end.
  • the distal end side is referred to as X1 side and the proximal end side is referred to as X2 side as appropriate.
  • a direction orthogonal to both the X direction and the Z direction is called a Y direction.
  • the Y direction is the width direction of the gas sensor element 1.
  • the X direction, the Y direction, and the Z direction are orthogonal to each other.
  • the electrolyte layer 2 includes the holding plate 22 and the solid electrolyte member 21.
  • the holding plate 22 has a plate shape that is long in the X direction and has a thickness in the Z direction. 2 to 4, the length of the gas sensor element 1 in the X direction is shorter than the actual length for convenience.
  • an arrangement hole 220 is formed in a region of the holding plate 22 on the X1 side in the X direction.
  • the arrangement hole 220 has a rectangular shape elongated in the X direction.
  • the arrangement hole 220 is filled with the solid electrolyte body 21.
  • the solid electrolyte member 21 is made of a zirconia-based oxide.
  • the solid electrolyte body 21 is composed of stabilized zirconia containing zirconia (ZrO 2 ) as a main component (that is, containing zirconia in an amount of 50% by mass or more) and partially replacing zirconia with a rare earth metal element or an alkaline earth metal element. It is made of a solid electrolyte such as partially stabilized zirconia.
  • a part of the zirconia constituting the solid electrolyte member 21 can be replaced by yttria (Y 2 O 3 ), scandia (Sc 2 O 3 ) or calcia (CaO).
  • the holding plate 22 is made of a material having higher thermal conductivity than the solid electrolyte body 21.
  • the measurement electrode 11 exposed to the gas G to be measured introduced into the measurement gas chamber 5 is arranged in a region on the X1 side of the surface on the Z1 side of the solid electrolyte body 21.
  • the reference electrode 12 exposed to the reference gas A introduced into the reference gas chamber 6 is arranged in a region on the X1 side of the surface on the Z2 side of the solid electrolyte body 21.
  • the measurement electrode 11 and the reference electrode 12 have a facing region 13 facing in the Z direction via the solid electrolyte body 21.
  • the side opposite to the X1 side in the X direction is referred to as the X2 side.
  • each of the measurement electrode 11 and the reference electrode 12 has an electrode lead portion 14 extending from the facing region 13 to the X2 side.
  • the pair of electrode leads 14 extend to near the X2 side end of the gas sensor element 1.
  • the pair of electrode leads 14 are connected to a pair of sensor terminals 15 formed on the surface of the first insulator 3 on the Z2 side through through holes formed in the second insulator 4.
  • the measurement electrode 11 and the reference electrode 12 are electrically connected to the outside of the gas sensor element 1 from a pair of sensor terminals 15.
  • the measurement electrode 11 and the reference electrode 12 contain platinum as a noble metal exhibiting catalytic activity against oxygen, and the same material as the solid electrolyte member 21, that is, zirconia-based oxide. Since the measurement electrode 11 and the reference electrode 12 contain the same material as that of the solid electrolyte member 21, the paste-like electrode material constituting the measurement electrode 11 and the reference electrode 12 is printed (coated) on the solid electrolyte member 21 and sintered. In this case, it is easy to secure the bonding strength between the measurement electrode 11 and the reference electrode 12 and the solid electrolyte member 21.
  • the first insulator 3 laminated on the surface on the Z1 side of the electrolyte layer 2 is formed by laminating the chamber forming portion 32 and the heater burying portion 31 in the Z direction.
  • the chamber forming section 32 is disposed on the surface of the electrolyte layer 2 on the Z1 side.
  • the chamber forming portion 32 includes an insulating spacer 321 having a concave portion 320 whose edge on the X1 side is concave on the X2 side, and a diffusion resistance disposed so as to close an open end of the concave portion 320 on the X1 side.
  • the diffusion resistance section 322 is configured to allow the gas G to be measured to pass at a predetermined diffusion speed.
  • the diffusion resistance section 322 is formed of a porous metal oxide such as alumina.
  • the exhaust gas as the gas to be measured G is introduced into the measurement gas chamber 5 through the diffusion resistance section 322.
  • the diffusion resistance portion 322 may be, for example, a pinhole that is a small through-hole that communicates with the measurement gas chamber 5 and the external space of the gas sensor element 1.
  • the position of the diffusion resistance portion 322 is not limited to this, and may be formed at another position such as one side of the measurement gas chamber 5 in the Y direction.
  • a space region surrounded by the insulating spacer 321 and the diffusion resistance portion 322 in the concave portion 320 is closed by the electrolyte layer 2 and the heater burying portion 31 from both sides in the Z direction to form the measurement gas chamber 5.
  • the chamber forming section 32 is disposed in a region where the measurement gas chamber 5 in the Z direction is formed, and partitions the measurement gas chamber 5.
  • the measurement gas chamber 5 when viewed from the Z direction, the measurement gas chamber 5 is formed so as to fit inside the boundary 23 between the arrangement hole 220 and the solid electrolyte member 21. Accordingly, as shown in FIGS. 1 and 2, the chamber forming portion 32 is formed so as to cover the entire boundary portion 23 from the Z1 side. Thereby, it is easy to prevent the measurement gas chamber 5 and the reference gas chamber 6 from communicating with each other via the boundary portion 23 due to a decrease in the airtightness of the boundary portion 23 in the electrolyte layer 2.
  • the outer shape of the measurement gas chamber 5 is indicated by a two-dot chain line
  • the outer shape of the reference gas chamber 6 is indicated by a broken line.
  • the length of the measurement gas chamber 5 in the Z direction is smaller than the thickness of the electrolyte layer 2 in the Z direction.
  • the measurement gas chamber 5 is formed so as to house at least the facing region 13 of the measurement electrode 11. In the present embodiment, when viewed from the Z direction, the measurement gas chamber 5 is formed to be slightly larger than the facing region 13 of the measurement electrode 11.
  • the heater embedded portion 31 is laminated on the Z1 side of the chamber forming portion 32.
  • the heater buried portion 31 is formed at the most Z1 side portion of the gas sensor element 1.
  • the heater embedded portion 31 includes a pair of embedded plates 311 stacked in the Z direction, and the heater 7 embedded between the pair of embedded plates 311. That is, the heater 7 is buried in the first insulator 3.
  • the heater 7 has a heat generating portion 71 that generates heat when energized, and a pair of lead portions 72 connected to the heat generating portion 71.
  • the heat generating portion 71 is arranged in a region overlapping the measurement gas chamber 5 in the Z direction. At least a part of the heat generating portion 71 is disposed so as to overlap in the Z direction with respect to the facing region 13 of the measurement electrode 11 and the facing region 13 of the reference electrode 12.
  • the heat generating portion 71 is disposed at a position where a part thereof overlaps the measurement gas chamber 5 in the Z direction, and another part is disposed at a position where the heat generating portion 71 overlaps the burying plate 311 of the chamber forming portion 32 in the Z direction.
  • Part of the heat generating portion 71 is formed on the X2 side of the measurement gas chamber 5. That is, a part of the heat generating portion 71 overlaps a portion of the embedded plate 311 adjacent to the measurement gas chamber 5 on the X2 side in the Z direction.
  • the heat generating portion 71 has a meandering shape that moves back and forth on both sides in the X direction as it goes to one side in the Y direction.
  • the shape of the heat generating portion 71 is not limited to this.
  • the shape of the heat generating portion 71 may be a meandering shape that moves back and forth on both sides in the Y direction as it goes to one side in the X direction, or may be another shape. is there.
  • a pair of lead portions 72 is formed from both ends of the heat generating portion 71.
  • the lead 72 is formed up to the end of the gas sensor element 1 on the X2 side.
  • the pair of lead portions 72 is connected to a pair of heater terminals 16 formed on the X1 side surface of the embedded plate 311 through the through holes of the embedded plate 311 on the X1 side.
  • the heater 7 is electrically connected to the outside of the gas sensor element 1 from the heater terminal 16.
  • the area of the cross section of the heat generating portion 71 perpendicular to the forming direction thereof is smaller than the area of the cross section of the heat generating portion 71 perpendicular to the forming direction of the lead 72.
  • the resistance value of the heating section 71 per unit length is larger than the resistance value of the lead section 72 per unit length.
  • the second insulator 4 laminated on the surface of the electrolyte layer 2 on the Z2 side has a duct forming portion 42 and a support portion 43.
  • the duct forming part 42 is arranged on the surface of the electrolyte layer 2 on the Z2 side.
  • the duct forming part 42 is arranged in a region where the reference gas chamber 6 in the Z direction is formed, and partitions the reference gas chamber 6. In the Z direction, the duct forming section 42 is longer than the length of the measurement gas chamber 5.
  • the duct forming part 42 is formed by sintering three layers having substantially the same shape in the Z direction and then sintering them.
  • the duct forming part 42 is formed in a U-shape that opens to the X2 side. That is, the duct forming portion 42 includes a pair of long side portions 421 extending in the X direction and facing each other in the Y direction, and a short side portion 422 connecting the X1 side ends of the pair of long side portions 421 in the Y direction. And As shown in FIG. 2, the surface on the X2 side of the short side portion 422 has a curved surface toward the X2 side toward the Z2 side. In the Z direction, the duct forming section 42 is longer than the length of the measurement gas chamber 5.
  • the reference gas chamber 6 is a space region inside the duct formation portion 42 formed by the electrolyte layer 2, the duct formation portion 42, and the support portion 43. As shown in FIG. 2, the reference gas chamber 6 is formed up to the X2 side end of the gas sensor element 1 and is open to the X2 side. Atmosphere as the reference gas A is introduced into the reference gas chamber 6 from an open portion on the X2 side of the duct forming portion 42.
  • both ends of the reference gas chamber 6 in the Y direction are located inside a pair of first boundary portions 231 facing each other in the Y direction in the boundary portion 23.
  • the duct formation part 42 is formed so that the whole of a pair of 1st boundary part 231 may be covered from Z2 side.
  • the X1 side edge of the reference gas chamber 6 in the X direction is located inside a pair of second boundary portions 232 of the boundary portion 23 facing in the X direction.
  • the duct forming portion (see reference numeral 42 in FIGS. 1, 2, and 4) forms the entire second boundary portion 232 on the X1 side of the pair of second boundary portions 232 as Z2.
  • the duct forming portion (see reference numeral 42 in FIGS. 1, 2, and 4) is the second boundary portion 232 on the X2 side of the pair of second boundary portions 232 in the boundary portion 23. Are formed so as to cover both end portions from the Z2 side.
  • the length of the first boundary 231 is longer than the length of the second boundary 232.
  • first boundary portions 231 in the boundary portion 23 are sandwiched between the first insulator 3 and the second insulator 4 from both sides in the Z direction.
  • the entire second boundary portion 232 on the X1 side of at least the pair of second boundary portions 232 includes the first insulator 3 and the second insulator 4. And is sandwiched by.
  • both ends of the second boundary portion 232 on the X2 side are formed of a first insulator (see reference numeral 3 in FIGS. 1, 2, and 4) and a second insulator (FIGS. 1 and 2). 2, reference numeral 4 in FIG. 4).
  • first boundary portions 231, the entire second boundary portion 232 on the X1 side, and both end portions of the second boundary portion 232 on the X2 side are in contact with the first insulator 3 from both sides in the Z direction. It is sandwiched by the second insulator 4.
  • a portion of the first insulator 3 that overlaps the boundary portion 23 in the chamber forming portion 32 and the heater embedding portion 31 in the Z direction is a first holding portion 33, and a duct forming portion 42 and a support portion 43 of the second insulator 4.
  • the portion that overlaps with the boundary portion 23 in the Z direction is the second holding portion 45.
  • Each of the first insulator 3 and the second insulator 4 is arranged so as to straddle the boundary portion 23 and sandwich the boundary portion 23. As shown in FIG. 2, a part of the first holding portion 33 located on the Z1 side of the second boundary portion 232 on the X1 side is configured by the diffusion resistance portion 322.
  • the length of the reference gas chamber 6 in the Z direction is larger than the length of the measurement gas chamber 5 in the Z direction.
  • the length of the reference gas chamber 6 in the Z direction is at least three times the length of the measurement gas chamber 5 in the Z direction, but is not limited thereto.
  • the length of the reference gas chamber 6 in the Y direction is slightly longer than the length of the reference electrode 12 in the Y direction.
  • the reference electrode 12 is located at the center of the reference gas chamber 6 in the Y direction.
  • the area of the cross section orthogonal to the X direction of the region on the X2 side of the short side portion 422 in the reference gas chamber 6 is larger than the area of the cross section of the measurement gas chamber 5 orthogonal to the X direction. Further, the entire reference gas chamber 6 has a larger volume than the entire measurement gas chamber 5. Since the above-described cross-sectional area, the length in the Z direction, the volume, and the like of the reference gas chamber 6 are larger than those of the measurement gas chamber 5, oxygen in the reference gas A for reacting unburned gas in the measurement electrode 11 , Can be sufficiently supplied from the reference gas chamber 6 to the measurement electrode 11.
  • a support portion 43 is laminated on the surface on the Z2 side of the duct formation portion.
  • the support portion 43 is formed at the most Z2 side portion of the gas sensor element 1.
  • the support part 43 closes the space inside the duct forming part 42, that is, the reference gas chamber 6 from the Z2 side.
  • the holding plate 22, the insulating spacer 321 in the chamber forming section 32, the burying plate 311, the duct forming section 42, and the supporting section 43 are made of the same material. Specifically, these are made of alumina (Al 2 O 3 ) having no permeability to the gas G to be measured.
  • a portion on the X1 side of the gas sensor element 1 contains a poisoning substance with respect to the measurement electrode (see reference numeral 11 in FIGS. 1, 2, and 4), condensed water generated in the exhaust pipe, and the like.
  • a protective layer 101 for preventing entry into the inside is provided.
  • the protective layer 101 is formed of a porous ceramic (metal oxide) such as alumina.
  • the porosity of the protective layer 101 is larger than the porosity of the diffusion resistance part 322, and the flow rate of the measured gas G that can pass through the protective layer 101 is equal to the measured gas G that can pass through the diffusion resistance part 322. More than the flow rate.
  • the axial direction of the gas sensor 10 is formed to be in the X direction.
  • the longitudinal direction of the gas sensor element 1 is parallel to the axial direction of the gas sensor 10.
  • the gas sensor 10 includes a gas sensor element 1, a first insulator 102, a housing 103, a second insulator 104, and a plurality of contact terminals 105.
  • the first insulator 102 holds the gas sensor element 1.
  • the housing 103 holds the first insulator 102.
  • the second insulator 104 is connected to the first insulator 102.
  • the plurality of contact terminals 105 are held by the second insulator 104 and are in contact with the sensor terminal 15 and the heater terminal 16 of the gas sensor element 1.
  • the gas sensor 10 includes a front end cover 106 attached to the X1 portion of the housing 103, a rear end cover 107 attached to the X2 side portion of the housing 103 to cover the second insulator 104, the contact terminal 105, and the like, and the contact terminal 105. And a bush 108 for holding the lead wire 100 connected to the rear end cover 107 to the rear end side.
  • the tip side cover 106 is disposed so as to be exposed inside the exhaust pipe of the internal combustion engine. A portion on the X1 side of the gas sensor element 1 protrudes inside the front end cover 106. A gas passage hole 106 a for allowing exhaust gas as the gas to be measured G to pass therethrough is formed in the distal end side cover 106.
  • the distal cover 106 may have a double structure or a single structure. Exhaust gas as the gas to be measured G flowing into the front cover 106 from the gas passage hole 106 a of the front cover 106 passes through the protective layer 101 and the diffusion resistance portion 322 of the gas sensor element 1 and is guided to the measurement electrode 11. .
  • the rear end side cover 107 is arranged outside the exhaust pipe of the internal combustion engine.
  • An air introduction hole 109 for introducing the atmosphere as the reference gas A into the rear end cover 107 is formed in the rear end cover 107.
  • a filter 109 a that allows gas to pass while the liquid does not pass is disposed in the air introduction hole 109.
  • the reference gas A introduced into the rear end cover 107 from the air introduction hole 109 is guided to the reference electrode 12 through the gap in the rear end cover 107 and the reference gas chamber 6.
  • a plurality of contact terminals 105 are arranged on the second insulator 104 so as to be connected to the heater terminal 16 and the sensor terminal 15, respectively.
  • the lead wire 100 is connected to the contact terminal 105.
  • the lead wire 100 is electrically connected to a sensor control device that controls gas detection in the gas sensor 10.
  • the sensor control device performs electric control in the gas sensor 10 in cooperation with an engine control device that controls combustion operation in the engine.
  • the sensor control device includes a measurement circuit for measuring a current flowing between the measurement electrode 11 and the reference electrode 12, an application circuit for applying a voltage between the measurement electrode 11 and the reference electrode 12, and a heater 7 for energizing the heater 7. Are formed. Note that the sensor control device may be built in the engine control device.
  • the operation and effect of the present embodiment will be described.
  • the first holding portion 33 is formed at least in the entire region where the measurement gas chamber 5 in the Z direction is arranged.
  • the second holding portion 45 is formed at least in the entire region where the reference gas chamber 6 in the Z direction is arranged. That is, at least a part of the boundary portion 23 is sandwiched between the first sandwiching portion 33 and the second sandwiching portion 45 which are formed of a relatively rigid structure. Therefore, it is easy to secure the rigidity of the first holding portion 33 and the second holding portion 45 that hold at least a part of the boundary portion 23, and it is easy to stably hold the solid electrolyte body 21 in the arrangement hole 220.
  • the electrolyte layer 2 has a solid electrolyte body 21 and a holding plate 22.
  • the holding plate 22 is made of a material having higher thermal conductivity than the solid electrolyte member 21. Therefore, it is easy to improve the heat conduction of the entire electrolyte layer 2. Therefore, it is easy to efficiently heat the solid electrolyte body 21 by the heater 7, and it is easy to activate the solid electrolyte body 21 early.
  • the boundary portion 23 can be held by the chamber forming portion 32 and the heater embedding portion 31 and the duct forming portion 42 and the support portion 43, the sheet only for holding the boundary portion 23 is replaced with the boundary portion. There is no need to dispose them on 23 surfaces, and it is possible to prevent an increase in the number of manufacturing steps and improve productivity.
  • the entirety of at least the pair of first boundary portions 231 in the boundary portion 23 is clamped by the first clamping portion 33 and the second clamping portion 45. Further, the whole of the second boundary portion 232 on the X1 side of the pair of first boundary portions 231 in the boundary portion 23 is clamped by the first clamping portion 33 and the second clamping portion 45. Therefore, the boundary portion 23 can be stably held by the first holding portion 33 and the second holding portion 45, and the solid electrolyte body 21 can be more easily prevented from dropping out of the arrangement hole 220.
  • the gas sensor element 1 has the heater 7 embedded in the first insulator 3. Therefore, the reference gas chamber 6 into which the relatively low-temperature reference gas A is introduced is not arranged between the heater 7 and the solid electrolyte member 21. Therefore, the thermal conductivity from the heater 7 to the solid electrolyte body 21 can be easily improved, and the solid electrolyte body 21 can be activated early.
  • this embodiment is an embodiment in which the shape of the electrolyte layer 2 is changed from the first embodiment.
  • the holding plate 22 is formed in a U-shape opened to the X2 side.
  • a region inside the U-shaped holding plate 22 is an arrangement hole 220 in which the solid electrolyte body 21 is arranged.
  • the arrangement hole 220 is formed up to the X2 side edge of the holding plate 22, and is open to the X2 side.
  • the arrangement hole 220 is filled with the solid electrolyte member 21.
  • the X2 side end of the solid electrolyte body 21 is formed up to the position of the X2 side of the holding plate 22.
  • the X2 side end of the solid electrolyte member 21 is not in contact with the holding plate 22 and is exposed from the holding plate 22 to the X2 side.
  • the boundary portion 23 is formed between a portion other than the edge on the X2 side of the solid electrolyte body 21 and the arrangement hole 220.
  • the entire boundary portion 23 is sandwiched by the first sandwiching portion 33 and the second sandwiching portion 45. That is, the entire boundary portion 23 is covered by the chamber forming portion 32 forming the first holding portion 33 from the Z1 side, and is covered by the duct forming portion 42 forming the second holding portion 45 from the Z2 side. .
  • the entire boundary portion 23 is sandwiched by the first sandwiching portion 33 and the second sandwiching portion 45. Therefore, the boundary portion 23 can be held more stably.
  • the third embodiment has the same functions and effects as the first embodiment.
  • the gas sensor detects whether the air-fuel ratio, which is the mixture ratio of fuel and air, in the engine is in a rich state with excess fuel or in a lean state with excess air relative to the stoichiometric air-fuel ratio. It can also be of a density cell type. Further, the gas sensor may be configured as a gas sensor other than the A / F sensor, such as a NOx sensor that detects the NOx concentration in exhaust gas.
  • a pump electrode for adjusting the oxygen concentration in the measurement gas chamber to a predetermined concentration or less and a NOx concentration are measured on the surface of the solid electrolyte body on the X1 side of the measurement gas chamber. And a measurement electrode are provided. In this case, in the gas sensor element, the NOx concentration of the gas to be measured is obtained based on a current value corresponding to the NOx concentration of the gas to be measured flowing between the measurement electrode and the reference electrode.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Molecular Biology (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Measuring Oxygen Concentration In Cells (AREA)
PCT/JP2019/031225 2018-08-23 2019-08-07 ガスセンサ素子 Ceased WO2020039942A1 (ja)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US17/181,212 US12031936B2 (en) 2018-08-23 2021-02-22 Gas sensor element

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2018156179A JP6917349B2 (ja) 2018-08-23 2018-08-23 ガスセンサ素子
JP2018-156179 2018-08-23

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US17/181,212 Continuation US12031936B2 (en) 2018-08-23 2021-02-22 Gas sensor element

Publications (1)

Publication Number Publication Date
WO2020039942A1 true WO2020039942A1 (ja) 2020-02-27

Family

ID=69593097

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2019/031225 Ceased WO2020039942A1 (ja) 2018-08-23 2019-08-07 ガスセンサ素子

Country Status (3)

Country Link
US (1) US12031936B2 (enExample)
JP (1) JP6917349B2 (enExample)
WO (1) WO2020039942A1 (enExample)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP7600914B2 (ja) 2021-07-15 2024-12-17 株式会社デンソー ガスセンサ

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0291557A (ja) * 1988-09-29 1990-03-30 Toyota Motor Corp 積層型酸素濃度センサの製造方法
JP2003294698A (ja) * 2002-03-29 2003-10-15 Ngk Spark Plug Co Ltd 積層型ガスセンサ素子及びその製造方法並びにガスセンサ
JP2010145214A (ja) * 2008-12-18 2010-07-01 Denso Corp ガスセンサ素子及びその製造方法
US8673128B2 (en) * 2011-09-27 2014-03-18 Denso Corporation Gas sensor element, gas sensor, and production method thereof
JP2016065816A (ja) * 2014-09-25 2016-04-28 日本特殊陶業株式会社 ガスセンサ素子、ガスセンサ及びガスセンサ素子の製造方法
JP2017223488A (ja) * 2016-06-14 2017-12-21 日本特殊陶業株式会社 ガスセンサ素子およびガスセンサ
JP2019002739A (ja) * 2017-06-13 2019-01-10 日本特殊陶業株式会社 センサ素子、及びそれを備えたガスセンサ
JP2019095359A (ja) * 2017-11-27 2019-06-20 日本特殊陶業株式会社 センサ素子、及びそれを備えたガスセンサ

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2017226507A (ja) * 2016-06-21 2017-12-28 株式会社日立ビルシステム エレベーター

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0291557A (ja) * 1988-09-29 1990-03-30 Toyota Motor Corp 積層型酸素濃度センサの製造方法
JP2003294698A (ja) * 2002-03-29 2003-10-15 Ngk Spark Plug Co Ltd 積層型ガスセンサ素子及びその製造方法並びにガスセンサ
JP2010145214A (ja) * 2008-12-18 2010-07-01 Denso Corp ガスセンサ素子及びその製造方法
US8673128B2 (en) * 2011-09-27 2014-03-18 Denso Corporation Gas sensor element, gas sensor, and production method thereof
JP2016065816A (ja) * 2014-09-25 2016-04-28 日本特殊陶業株式会社 ガスセンサ素子、ガスセンサ及びガスセンサ素子の製造方法
JP2017223488A (ja) * 2016-06-14 2017-12-21 日本特殊陶業株式会社 ガスセンサ素子およびガスセンサ
JP2019002739A (ja) * 2017-06-13 2019-01-10 日本特殊陶業株式会社 センサ素子、及びそれを備えたガスセンサ
JP2019095359A (ja) * 2017-11-27 2019-06-20 日本特殊陶業株式会社 センサ素子、及びそれを備えたガスセンサ

Also Published As

Publication number Publication date
US12031936B2 (en) 2024-07-09
US20210181140A1 (en) 2021-06-17
JP2020030123A (ja) 2020-02-27
JP6917349B2 (ja) 2021-08-11

Similar Documents

Publication Publication Date Title
JP4828753B2 (ja) ガス混合気中の酸素濃度を規定するためのセンサ部材および該センサ部材を製造するための方法
EP0310206B1 (en) Electrochemical device
JPS58153155A (ja) 酸素センサ
JPH08271476A (ja) 被測定ガス中の所定ガス成分の測定方法及び測定装置
CN111295583B (zh) 气体传感器
CN115087863B (zh) 气体传感器元件
JP3631582B2 (ja) ガスセンサ
JP7089988B2 (ja) ガスセンサ素子
JP2020071128A (ja) ガスセンサ素子
US20190391109A1 (en) Gas sensor
JP7125372B2 (ja) ガスセンサ
JP7138055B2 (ja) ガスセンサ
WO2020039942A1 (ja) ガスセンサ素子
JPH0222692Y2 (enExample)
JP6814086B2 (ja) ガスセンサ素子およびガスセンサ
JP6517613B2 (ja) ガスセンサ
JPS6382355A (ja) ガスセンサ
JP4101501B2 (ja) 複合ガスセンサ素子
JP6438851B2 (ja) ガスセンサ素子及びガスセンサ
JP7068132B2 (ja) ガスセンサ
JP2003021613A (ja) ガスセンサ素子
JP7089949B2 (ja) ガスセンサ
JP3509329B2 (ja) 酸素濃度検出素子
JP6640665B2 (ja) ガスセンサ
WO2020195080A1 (ja) ガスセンサ

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 19851135

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 19851135

Country of ref document: EP

Kind code of ref document: A1