JP2017223488A - Gas sensor element and gas sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To raise the temperature of a sensor cell effectively.SOLUTION: A gas sensor element 10 comprises: a heating layer 140 having a heating element 141; a first ceramic layer 120 that is in contact with the heating layer 140 and has a measurement chamber 121 into which gas to be measured is introduced; a sensor cell layer 110 that is in contact with the first ceramic layer 120 and has a solid electrolyte part 131 and a pair of electrodes 114 and 115, at least the electrode 114 being placed on a surface of the solid electrolyte part 131 facing the measurement chamber 121. The gas sensor element 10 also comprises a second ceramic layer 130 that is in contact with the sensor cell layer 110 and has a space 131a larger than the size of the measurement chamber 121.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a gas sensor element and a gas sensor.

  A gas sensor having a gas sensor element that outputs a concentration of a specific component in exhaust gas discharged from an internal combustion engine, for example, a concentration of oxygen, as a measurement signal is known. The gas sensor element is generally provided with a sensor cell having a solid electrolyte used for concentration measurement, and a heater for raising the temperature of the solid electrolyte to an activation temperature (for example, Patent Documents 1 and 2). .

Japanese Patent No. 4716286 Japanese Patent No. 4007892

  However, in the conventional gas sensor element, a space for introducing air is arranged between the sensor cell and the heater, or the distance between the sensor cell and the heater is large. As a result, the heat energy of the heater is not efficiently transmitted to the sensor cell, and there is a problem that it takes time to activate the solid electrolyte and measure the concentration of the specific component.

  Therefore, a technique for efficiently increasing the temperature of the sensor cell is desired.

  The present invention has been made to solve the above-described problems, and can be realized as the following aspects.

  A first aspect provides a gas sensor element. A gas sensor element according to a first aspect includes a heat generating layer including a heat generating element, a first ceramic layer disposed in contact with the heat generating layer and having a measurement chamber into which a gas to be measured is introduced, and the first ceramic. A sensor cell layer disposed in contact with the layer and having a solid electrolyte portion, and a pair of electrodes in which at least one electrode is disposed on a surface of the solid electrolyte portion facing the measurement chamber, and in contact with the sensor cell layer And a second ceramic layer having a space part having a volume larger than that of the measurement chamber.

  In the gas sensor element according to the first aspect, the first ceramic layer having the measurement chamber into which the gas to be measured is introduced is disposed in contact with the heat generating layer, and the solid electrolyte portion and the surface facing the measurement chamber in the solid electrolyte portion are arranged. A sensor cell layer having a pair of electrodes on which at least one electrode is disposed is disposed in contact with the first ceramic layer. On the other hand, the 2nd ceramic layer which has a space part with a larger volume than a measurement chamber is arrange | positioned in contact with the surface on the opposite side to the surface which contact | connects the 1st ceramic layer in a sensor cell layer. Therefore, the measurement chamber having a smaller volume than the space portion is interposed between the heat generation layer and the solid electrolyte portion, and the space portion having a large volume is interposed between the heat generation layer and the solid electrolyte portion. In comparison, the temperature of the sensor cell can be increased efficiently.

  In the gas sensor element according to the first aspect, the gas sensor element has a long plate shape, and a cross-sectional area of the space portion in a cross section orthogonal to the longitudinal direction of the gas sensor element may be larger than a cross-sectional area of the measurement chamber. . In this case, since the space part larger than the measurement chamber in the cross-sectional area is not interposed between the heat generating layer and the solid electrolyte part, the temperature of the sensor cell can be increased efficiently.

  In the gas sensor element according to the first aspect, the space portion may be an air introduction chamber into which air is introduced. In this case, even when the gas sensor element has a configuration in which the atmosphere is introduced, the temperature of the sensor cell can be increased efficiently.

  In the gas sensor element according to the first aspect, the solid electrolyte portion has a first surface facing the measurement chamber and a second surface facing the space portion, and the pair of electrodes includes the pair of electrodes, You may provide the 1st electrode and 2nd electrode which are each arrange | positioned at the said 1st surface and the said 2nd surface of a solid electrolyte part. In this case, the concentration of the gas component to be measured can be measured with a simple configuration.

  In the gas sensor element according to the first aspect, the first ceramic layer may include an introduction path that is parallel to the first ceramic layer and has a porous portion, and that communicates with the measurement chamber. good. In this case, the porous portion can be used as a diffusion-controlling layer that introduces the gas to be measured into the measurement chamber under a predetermined rate-controlling condition.

  The gas sensor element which concerns on a 1st aspect WHEREIN: The said solid electrolyte part may be arrange | positioned in the penetration area | region provided in the said sensor cell layer. In this case, the thickness of the gas sensor element can be reduced as compared with the case where the dimension in the thickness direction of the sensor cell layer is set to one layer thickness, that is, the solid electrolyte portion is not embedded in the sensor cell layer. .

  In the gas sensor element according to the first aspect, a porous material may be disposed in at least a part of the space portion. In this case, the strength of the gas sensor element can be improved by the presence of the porous material in the space having a large volume.

  A second aspect provides a gas sensor. The gas sensor according to the second aspect includes the gas sensor element according to the first aspect. In this case, the rising time until the measurement of the concentration of the gas to be measured in the gas sensor becomes possible can be shortened.

It is the longitudinal cross-sectional view which cut | disconnected the gas sensor 1 in the 1st Embodiment of this invention by the plane in alignment with the axis line AX. It is a disassembled perspective view which shows each member which comprises a gas sensor element. It is an external view of a gas sensor element. It is a longitudinal cross-sectional view which shows typically the lamination | stacking state of each member which comprises the gas sensor element cut | disconnected by the 4-4 cutting line in FIG. It is a cross-sectional view which shows typically the lamination | stacking state of each member which comprises the gas sensor element cut | disconnected by the 5-5 cutting line in FIG. It is explanatory drawing which shows typically the cross section of the gas sensor element as a comparative example. It is explanatory drawing for verifying the temperature rising efficiency in the analysis object 1 and the analysis object 2. FIG.

First embodiment:
FIG. 1 is a longitudinal sectional view of the gas sensor 1 according to the first embodiment of the present invention cut along a plane along the axis AX. For example, the gas sensor 1 is mounted on an exhaust pipe of an internal combustion engine and used as an oxygen sensor. Hereinafter, the detection end side (side on which the sensor cell is disposed) of the gas sensor 1 will be described as the distal end side DL1, and the side on which the lead wires 78 and 79 extend will be described as the proximal end side DL2.

  The gas sensor 1 mainly includes a gas sensor element 10 and a metal shell 20. The gas sensor element 10 is a long plate-like element, and has a sensor cell for measuring the oxygen concentration in the exhaust gas that is the gas to be measured. The gas sensor element 10 has a distal end portion 10s where a sensor cell is disposed, a sensor pad portion 15 electrically connected to lead wires 78 and 79, and a proximal end portion 10k where a heater pad portion 17 is disposed. The gas sensor element 10 is held by the metal shell 20 with the distal end portion 10 s projecting from the distal end side of the metal shell 20 and the base end portion 10 k projecting from the proximal end side of the metal shell 20. The gas sensor element 10 is also disposed in the gas sensor 1 so that the center line of the gas sensor element 10 along the longitudinal direction DL coincides with the axis AX of the gas sensor 1.

  The metal shell 20 is a cylindrical metal fitting that holds the gas sensor element 10 inside. A metallic external protector 31 and an internal protector 32 are disposed on the distal end side of the metal shell 20 and cover the distal end portion 10 s of the gas sensor element 10. The external protector 31 and the internal protector 32 have a plurality of gas introduction holes 31h and 32h. The gas to be measured outside the external protector 31 is introduced to the periphery of the tip portion 10s of the gas sensor element 10 disposed inside the internal protector 32 through the gas introduction holes 31h and 32h.

  Inside the metal shell 20, an annular ceramic holder 21, powder filling layers 22 and 23 (hereinafter also referred to as talc rings 22 and 23), and a ceramic sleeve 24 so as to surround the outer periphery of the gas sensor element 10, They are arranged in this order from the distal end side DL1 to the proximal end side DL2. A metal holder 25 is disposed on the outer periphery of the ceramic holder 21 and the talc ring 22. A caulking packing 26 is disposed on the proximal end side of the ceramic sleeve 24. The base end portion 27 of the metal shell 20 is crimped so as to press the ceramic sleeve 24 toward the distal end side via the crimping packing 26.

  A cylindrical outer cylinder 51 is disposed on the base end side of the metal shell 20 so as to surround the base end portion 10 k of the gas sensor element 10. Further, a separator 60 is disposed inside the outer cylinder 51. The separator 60 surrounds the periphery of the base end portion 10k of the gas sensor element 10, and four terminal members 75 and 76 (only two are shown in FIG. 1) attached to the tips of four lead wires 78 and 79 (only two are shown in FIG. 1). In FIG. 1, only two are shown) and are held apart from each other. The separator 60 has an insertion hole 62 that penetrates in the axis AX direction. The base end portion 10k of the gas sensor element 10 is inserted into the insertion hole 62. In the insertion hole 62, four terminal members 75 and 76 are arranged so as to be separated from each other, and elastically abut against the sensor pad portions 14 and 15 and the heater pad portions 16 and 17 of the gas sensor element 10, respectively. Connection is realized. On the proximal end side of the outer cylinder 51, a grommet 73 that closes the proximal end opening of the outer cylinder 51 is fitted. The four lead wires 78 and 79 pass through the grommet 73. The base end portion 10k of the gas sensor element 10 and the atmosphere communicate with each other through a communication path (not shown).

  FIG. 2 is an exploded perspective view showing each member constituting the gas sensor element. FIG. 3 is an external view of the gas sensor element. FIG. 4 is a longitudinal sectional view schematically showing a laminated state of each member constituting the gas sensor element, taken along a cutting line 4-4 in FIG. FIG. 5 is a cross-sectional view schematically showing a stacked state of each member constituting the gas sensor element, taken along the line 5-5 in FIG. 2 to 4, the left side is the distal end side DL1 of the gas sensor 1, and the right side is the proximal end side DL2.

  The gas sensor element 10 includes a plurality of ceramic layers and conductor layers stacked in a thickness direction (also referred to as a stacking direction) DT. Specifically, the gas sensor element 10 includes a sensor cell layer 110, a first insulating ceramic layer 120, a second insulating ceramic layer 130, and a heat generating layer 140. 2, the first insulating ceramic layer 120 above the heat generating layer 140, the sensor cell layer 110 above the first insulating ceramic layer 120, and the second insulating ceramic layer above the sensor cell layer 110 in FIG. 2. Laminated in the order of 130. Each of the layers 110, 120, 130 and 140 is made of an insulating ceramic such as alumina and has a rectangular plate shape having the same external dimensions (at least width and length).

  The sensor cell layer 110 has a sensor cell 111 used for detecting the oxygen concentration in the gas to be measured. The sensor cell layer 110 includes a rectangular through-hole region 112h penetrating the substrate 112 of the sensor cell layer 110 in the thickness direction DT on the distal end side and a circular through hole 112x on the proximal end side in a planar view. The opening area of the through region 112h is sufficiently larger than the opening area of the through hole 112x. The sensor cell layer 110 further includes a plate-like solid electrolyte portion 113 made of a solid electrolyte (zirconia) ceramic disposed in the through region 112h. The substrate 112 has a first substrate surface 112 a facing the first insulating ceramic layer 120 and a second substrate surface 112 b facing the second insulating ceramic layer 130. The solid electrolyte portion 113 has a first solid electrolyte surface 113a that is flush with the first substrate surface 112a and a second solid electrolyte surface 113b that is flush with the second substrate surface 112b. A pair of thin film-like first electrode 114 and second electrode 115 are disposed on the first base surface 112a and the second base surface 112b, respectively. The first electrode 114 and the second electrode 115 have wide electrode portions 114m and 115m and linear (band-like) lead portions 114n and 115n, respectively, and the electrode portion 114m is on the first solid electrolyte surface 112a. The electrode portion 115m is disposed on the second solid electrolyte surface 112b. In the present specification, the sensor cell 111 is configured by the solid electrolyte portion 113, the first electrode 114, and the second electrode 115. The first electrode 114 and the second electrode 115 can be formed of a noble metal such as platinum, a transition metal, and an alloy containing two or more of these metals. The first electrode 114 is electrically connected to a sensor pad portion 14 to be described later through the through hole 112x. The first and second solid electrolyte surfaces 113a and 113b respectively correspond to the first and second surfaces of the solid electrolyte portion in the claims.

  The first insulating ceramic layer 120 has a measurement chamber 121 into which a gas to be measured is introduced. The first insulating ceramic layer 120 is disposed between the first base body 122m and the second base body 122n larger than the first base body, and the first base body 122m and the second base body 122n arranged in the longitudinal direction. And a porous portion 123 made of two insulating ceramics. The measurement chamber 121 is defined by the first and second substrates 122m and 122n, the two porous portions 123, the heat generating layer 140, and the first substrate surface 112a. The volume of the measurement chamber 121 is a volume of a space defined by the first and second substrates 122m and 122n, the heat generating layer 140, the first substrate surface 112a, and the outer surfaces of the two porous portions 123. That is, the volume when it is assumed that the two porous portions 123 do not exist is determined as the volume of the measurement chamber 121. A measurement gas is introduced into the measurement chamber 121 via the porous portion 123, and the porous portion 123 introduces the measurement gas into the measurement chamber 121 from the outside of the gas sensor element 10 under a predetermined rate-limiting condition. It is. The measurement chamber 121 is formed at a position facing the solid electrolyte portion 113 provided in the sensor cell layer 110 in the stacking direction. That is, the solid electrolyte part 113 is disposed so as to cover the measurement chamber 121. The first insulating ceramic layer 120 has a thinner thickness than the other layers.

  The second insulating ceramic layer 130 includes a frame body layer 130a whose one surface is in contact with the sensor cell layer 110 and a protective layer 130b which is in contact with the other surface of the frame layer 130a. The outer surface of the protective layer 130 b, that is, the surface that does not face the frame layer 130 a constitutes one outer surface of the gas sensor element 10. The frame layer 130a has a space region corresponding to the atmosphere introduction chamber 131a into which the atmosphere as the reference gas is introduced and the atmosphere introduction portion 131b that guides the atmosphere from the outside of the gas sensor 1 to the atmosphere introduction chamber 131a. The air introduction chamber 131a and the air introduction portion 131b are partitioned by the space region being blocked by the protective layer 130b and the second base surface 112b. At least one of the air introduction chamber 131a and the air introduction portion 131b corresponds to a space provided in the second insulating ceramic layer 130. The volume of the space is the volume of at least one of the atmosphere introduction chamber 131a and the atmosphere introduction portion 131b. As for the air introduction part 131b in the frame body layer 130a, the opening part of the air introduction part 131b is closed by a virtual surface connecting the base end side end face of the protective layer 130b and the base end side end face of the base 112. Is partitioned. As described above, the air introduction part 131b communicates with the outside (atmosphere) of the gas sensor 1 via a communication path (not shown), and the porous material 134 is disposed therein. Here, similarly to the volume of the measurement chamber 121, the volume of the air introduction part 131b that is assumed to be free of the porous material 134 is the volume of the air introduction part 131b. Note that the volume of the air introduction chamber 131 a is larger than the volume of the measurement chamber 121. Through holes 132x, 132y, 133x, and 133y having a circular shape in plan view are formed on the base end side of the frame body layer 130a and the base end side of the protective layer 130b, respectively. The through holes 132x and 133x are formed at positions corresponding to the through holes 112x formed in the sensor cell layer 110. The through holes 132y and 133y are used to electrically connect the second electrode 115 and a sensor pad portion 15 described later.

  The heat generating layer 140 includes a first heat generating layer 140a, a second heat generating layer 140b, and a heat generating element 141 disposed between the first heat generating layer 140a and the second heat generating layer 140b. One surface of the first heat generation layer 140a is in contact with and faces the first insulating ceramic layer 120, and the other surface is in contact with and faces one surface of the heat generating element 141 and the second heat generation layer 140b. ing. One surface, that is, the inner surface of the second heat generation layer 140b is in contact with the other surface of the first heat generation layer 140a and the heating element 141, and the other surface, that is, the outer surface, is in contact with the gas sensor element 10. Constituting the other outer surface. On the base end side of the second heat generating layer 140b, through holes 142x and 142y having a circular shape in plan view are formed. Heater pad portions 16 and 17 are disposed in the through holes 142x and 142y on the outer surface of the second heat generating layer 140b.

  The heating element 141 includes a heating part 141m having a meandering pattern and two lead parts 141n connected to both ends of the heating part 141m and extending linearly. The heat generating portion 141m of the heat generating body 141 is electrically connected to the heater pad portions 16 and 17 through the lead portion 141n and the through holes 142x and 142y. The heating element 141 heats the solid electrolyte part 113 by supplying current to the heating part 141m through the two lead wires 79 electrically connected to the heater pad parts 16 and 17 to generate heat when measuring the oxygen concentration. And activate.

  In the gas sensor element 10 according to the present embodiment, the sensor cell 111 is disposed between the atmosphere introduction chamber 131a and the measurement chamber 121 due to its configuration. Therefore, the heat generation layer 140 is disposed with respect to the sensor cell layer 110 via the measurement chamber 121 or the atmosphere introduction chamber 131a. That is, the heat generating layer 140 is disposed outside the first insulating ceramic layer 120 not facing the sensor cell layer 110 or outside the second insulating ceramic layer 130 not facing the sensor cell layer 110. It will be. In the present embodiment, in order to improve the heating efficiency of the solid electrolyte part 113 by the heat generating element 141, the heat generating layer 140 has a space with a smaller volume, that is, a measurement chamber 121 with a smaller volume than the atmosphere introduction chamber 131a. It is arranged between. As a result, the gas sensor element 10 according to the present embodiment forms a stacked body in which the heat generating layer 140, the first insulating ceramic layer 120, the sensor cell layer 110, and the second insulating ceramic layer 130 are stacked in this order.

  A conductor is embedded in each of the through holes 112x, 132x and 133x, 132y and 133y, and 142x and 142y. Therefore, the sensor pad portion 14 is electrically connected to the lead portion 114n of the first electrode 114 through the conductor embedded in the through holes 112x, 132x, and 133x, and the sensor pad portion 15 is embedded in the through holes 132y and 133y. It is electrically connected to the lead portion 115n of the second electrode 115 through the connected conductor. The heater pad portions 16 and 17 are electrically connected to the lead portion 141n of the heating element 141 through conductors embedded in the through holes 142x and 142y, respectively.

  The gas sensor element 10 according to the first embodiment described above includes the heat generating layer 140 on the outer side of the first insulating ceramic layer 120 that does not face the sensor cell layer 110. That is, the measurement chamber 121 having a smaller volume than the air introduction chamber 131a is disposed between the heat generating layer 140 and the solid electrolyte portion 113. FIG. 6 is an explanatory view schematically showing a cross section of a gas sensor element as a comparative example. As a result, as compared with the gas sensor element 40 shown in FIG. 6, the atmosphere introduction chamber 41 having a larger volume than the measurement chamber 44 is disposed between the heating layer 42 including the heating element 421 and the solid electrolyte part 43. The temperature raising efficiency of the solid electrolyte part 113 can be improved. That is, the thermal conductivity of air is 0.0241 (W / m · K), compared with platinum with a thermal conductivity of 72 (W / m · K) and 3 (W / m · K) with zirconia. Therefore, the thermal conductivity is very low. Therefore, when a large volume air chamber exists between the solid electrolyte part to be heated and the heating element, the temperature raising efficiency is reduced, and the time and power (energy) are increased for the temperature to be raised. It will be necessary.

  With reference to FIG. 7, it demonstrates still in detail about the improvement of the temperature increase efficiency in the gas sensor element 10 which concerns on 1st Embodiment. FIG. 7 is an explanatory diagram for verifying the temperature increase efficiency in the analysis object 1 and the analysis object 2. The temperature elevating efficiency was examined by analytical simulation. In FIG. 7, the horizontal axis represents the supply power (W) to the heating element, and the vertical axis represents the average temperature (° C.) of the electrodes located far from the heating element among the pair of electrodes arranged on both surfaces of the solid electrolyte part. ). In FIG. 7, the characteristic line L1 indicates the analysis result of the analysis target 1, and the characteristic line L2 indicates the analysis result of the analysis target 2. The analysis target 1 corresponds to the gas sensor element 10 according to this embodiment, and the analysis target 2 corresponds to the gas sensor element 40 according to the comparative example.

  The analysis object 1 includes a heating element (heating element 141), one electrode (first electrode 114), a solid electrolyte part (solid electrolyte part 113), another electrode (second electrode 115), and a large capacity chamber ( The stacking order of the atmosphere introduction chamber 131a) is simulated, and the analysis object 2 includes a heating element (421), a large capacity chamber (41), one electrode (431), a solid electrolyte part (43), and another electrode ( 432) is simulated. In addition, the inside of () shows the corresponding structure in the gas sensor element 10 which concerns on 1st Embodiment, and the gas sensor element 40 which concerns on a comparative example, respectively. Specifically, the thermal conductivity of platinum forming the electrode, the thermal conductivity of zirconia forming the solid electrolyte part, and the thermal conductivity of air corresponding to the large capacity chamber are applied to the stacking order of each analysis target, The average temperature of the other electrode located far from the heating element in the pair of electrodes was simulated with respect to the amount of heat (electric power) given by the heating element. Since the other electrode is disposed on the surface of the solid electrolyte part far from the heating element and heat is conducted through the solid electrolyte part, the temperature of the solid electrolyte part can be estimated by the temperature of the other electrode. As is clear from FIG. 7, for the same calorific value (power (W)), the analysis object 1 (characteristic line L1) in which no large capacity chamber exists between the heating element and the solid electrolyte part is The temperature was higher than that of the analysis object 2 (characteristic line L2) in which a large-capacity chamber exists between the solid electrolyte part, and it was confirmed that the temperature rise efficiency of the solid electrolyte part was improved. As a result, the same temperature increase can be realized with lower power, and the temperature raising efficiency can be improved. Further, the same temperature increase can be realized with lower power in a shorter time, and the temperature raising efficiency can be improved.

・ Modification:
(1) In the first embodiment, each of the layers 110, 120, 130, and 140 is formed of an insulating ceramic such as alumina, but may be formed of a conductive ceramic such as zirconia. In this case, an insulating layer is disposed between the layers 110, 120, 130 and 140.

(2) In the first embodiment, the atmosphere is introduced into the atmosphere introduction chamber 131a by the atmosphere introduction portion 131b extending in the longitudinal direction (horizontal direction) of the gas sensor element 10, but in the middle of the atmosphere introduction portion 131b. An air introduction part that extends in a direction (for example, a vertical direction) intersecting with the longitudinal direction from may be used. That is, if the air introduction chamber 131a that overlaps the solid electrolyte portion 113 is arranged in the stacking direction, it is possible to enjoy the benefits of improving the temperature rise efficiency according to the first embodiment. Various modes can be taken for the introduction path for guiding the atmosphere.

(3) In the first embodiment, the measurement chamber 121 is defined by the first base body 122m, the second base body 122n, and the two porous portions 123, but includes the porous portion 123. Alternatively, a through region may be provided on one substrate to form the measurement chamber 121. In this case, the gas to be measured can be introduced into the measurement chamber 121 through a communication path that penetrates in the separately formed stacking direction and communicates with the outside of the gas sensor element 10, for example.

(4) In the first embodiment, the example in which the concentration of oxygen is measured as the measurement gas component measured by the gas sensor element 10 has been described, but other gas components other than oxygen may be detected.

(5) In the first embodiment, the atmosphere introduction chamber 131a and the atmosphere introduction portion 131b have been described separately. However, only the atmosphere introduction path having the same width over the entire length may be provided. Even in this case, the volume of the air introduction part 131b is larger than the volume of the measurement chamber 121, and the effect of the gas sensor element 10 according to the first embodiment can be obtained.

(6) In the first embodiment, the porous material 134 is disposed in the air introduction part 131b. However, the porous material 134 may not be disposed. Further, the porous material 134 may be disposed in the air introduction chamber 131a instead of the air introduction portion 131b, or may be disposed in both the air introduction chamber 131a and the air introduction portion 131b.

  As mentioned above, although this invention was demonstrated based on embodiment and a modification, embodiment mentioned above is for making an understanding of this invention easy, and does not limit this invention. The present invention can be changed and improved without departing from the spirit and scope of the claims, and equivalents thereof are included in the present invention. For example, the technical features in the embodiments and the modifications corresponding to the technical features in each embodiment described in the summary section of the invention are to solve some or all of the above-described problems, or In order to achieve part or all of the effects, replacement or combination can be performed as appropriate. Further, if the technical feature is not described as essential in the present specification, it can be deleted as appropriate.

DESCRIPTION OF SYMBOLS 1 ... Gas sensor 10 ... Gas sensor element 10k ... Base end part 10s ... Tip part 14, 15 ... Sensor pad part 16, 17 ... Heater pad part 20 ... Main metal fitting 21 ... Ceramic holder 22 ... Powder-packed layer 22 ... Tarnish ring 24 ... Ceramic Sleeve 25 ... Metal holder 26 ... Casting packing 27 ... Base end 31 ... External protector 31h ... Gas introduction hole 32 ... Internal protector 40 ... Gas sensor element 41 ... Air introduction chamber 42 ... Heat generation layer 421 ... Heating element 43 ... Solid electrolyte part 44 ... Measuring chamber 51 ... Outer cylinder 60 ... Separator 62 ... Insertion hole 73 ... Grommet 75 ... Terminal member 78, 79 ... Lead wire 110 ... Sensor cell layer 111 ... Sensor cell 112 ... Base 112a ... First base surface 112b ... Second Substrate surface 112h ... through region 112x ... through hole 113 ... solid electrolyte part 11 3a ... 1st solid electrolyte surface 113b ... 2nd solid electrolyte surface 114 ... 1st electrode 114m ... Electrode part 114n ... Lead part 115 ... 2nd electrode 115m ... Electrode part 115n ... Lead part 120 ... 1st insulation Ceramic layer 121 ... Measurement chamber 122m ... First substrate 122n ... Second substrate 123 ... Porous part 130 ... Second insulating ceramic layer 130a ... Frame body layer 130b ... Protective layer 131a ... Air introduction chamber 131b ... Air introduction Part 131x, 131y, 132x, 132y ... Through hole 134 ... Porous material 140 ... Heat generating layer 140a ... First heat generating layer 140b ... Second heat generating layer 141 ... Heat generating element 141m ... Heat generating part 141n ... Lead part 142x ... Through hole AX ... axis DL ... longitudinal direction DL1 ... distal end side DL2 ... proximal end DT ... thickness (lamination) direction L1 ... characteristic line L2 ... characteristic line

Claims (8)

A gas sensor element,
A heating layer including a heating element;
A first ceramic layer disposed in contact with the heat generating layer and having a measurement chamber into which a gas to be measured is introduced;
A sensor cell layer disposed in contact with the first ceramic layer and having a solid electrolyte portion and a pair of electrodes in which at least one electrode is disposed on a surface of the solid electrolyte portion facing the measurement chamber; and the sensor cell A gas sensor element comprising: a second ceramic layer disposed in contact with the layer and having a space portion having a volume larger than that of the measurement chamber. The gas sensor element according to claim 1, wherein
The gas sensor element has a long plate shape,
The gas sensor element, wherein a cross-sectional area of the space portion in a cross section orthogonal to the longitudinal direction of the gas sensor element is larger than a cross-sectional area of the measurement chamber. The gas sensor element according to claim 1 or 2,
The space part is a gas sensor element which is an atmosphere introduction chamber into which the atmosphere is introduced. In the gas sensor element according to any one of claims 1 to 3,
The solid electrolyte portion has a first surface facing the measurement chamber and a second surface facing the space portion,
The pair of electrodes includes a first electrode and a second electrode disposed on the first surface and the second surface of the solid electrolyte portion, respectively. In the gas sensor element according to any one of claims 1 to 4,
The gas element sensor, wherein the first ceramic layer includes an introduction path that is parallel to the first ceramic layer and has a porous portion and communicates with the measurement chamber. In the gas sensor element according to any one of claims 1 to 5,
The said solid electrolyte part is a gas sensor element arrange | positioned in the penetration area | region provided in the said sensor cell layer. In the gas sensor element according to any one of claims 1 to 6,
A gas sensor element, wherein a porous material is disposed in at least a part of the space.   A gas sensor comprising the gas sensor element according to claim 1.

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