JP4355623B2

JP4355623B2 - Gas sensor

Info

Publication number: JP4355623B2
Application number: JP2004189580A
Authority: JP
Inventors: 浩磯村; 正二赤塚; 修新海
Original assignee: NGK Spark Plug Co Ltd
Current assignee: Niterra Co Ltd
Priority date: 2003-07-04
Filing date: 2004-06-28
Publication date: 2009-11-04
Anticipated expiration: 2024-06-28
Also published as: JP2005043349A

Description

本発明は、ガスセンサに関し、特に、有底筒状または板状をなすガスセンサ素子のうちで被測定ガスに晒される部位を覆うプロテクタを備えるガスセンサに関する。 The present invention relates to a gas sensor, and more particularly, to a gas sensor including a protector that covers a portion exposed to a gas to be measured among gas sensor elements having a bottomed cylindrical shape or a plate shape.

従来より、酸素センサ、ＮＯｘセンサ、ＨＣセンサなどのガスセンサが知られている。このようなガスセンサでは、一般に、ガスセンサ素子のうちで排ガス等の被測定ガスに晒される先端部を保護するため、この先端部を覆うようにプロテクタが装着されている。プロテクタには、センサの応答性やガスセンサ素子に対する耐被水性などを考慮して２重構造としたものがある。例えば、特許文献１に、このような２重構造からなるプロテクタを有するガスセンサが開示されている。 Conventionally, gas sensors such as oxygen sensors, NOx sensors, and HC sensors are known. In such a gas sensor, in order to protect the front-end | tip part exposed to to-be-measured gas, such as waste gas, among gas sensor elements generally, the protector is mounted | worn so that this front-end | tip part may be covered. Some protectors have a double structure in consideration of responsiveness of the sensor and water resistance to the gas sensor element. For example, Patent Document 1 discloses a gas sensor having a protector having such a double structure.

このガスセンサは、保護管（プロテクタ）が外側保護管（外側カバー部）と内側保護管（内側カバー部）とからなる。このうち、外側保護管は、その後端部が主体金具の先端縁の外周面に溶接されることにより固着されている。一方、内側保護管は、その先端部の外面が外側保護管の先端部の内面に溶接されることによって固着されている。つまり、この保護管は、内側保護管が先端部で外側保護管に固着され、さらに、外側保護管が後端部で主体金具に固着されることによって、主体金具に固定されている。 In this gas sensor, the protective tube (protector) includes an outer protective tube (outer cover portion) and an inner protective tube (inner cover portion). Among these, the outer protective tube is fixed by welding the rear end portion thereof to the outer peripheral surface of the front end edge of the metal shell. On the other hand, the outer surface of the front end portion of the inner protective tube is fixed by welding to the inner surface of the front end portion of the outer protective tube. In other words, the protective tube is fixed to the metal shell by fixing the inner protective tube to the outer protective tube at the front end and further fixing the outer protective tube to the metal shell at the rear end.

特開２００２−１６２３７７号公報JP 2002-162377 A

しかしながら、このようなガスセンサに長期間あるいは大きな振動が加わった場合などには、内側保護管と外側保護管の溶接部分が破断することがある。すると、内側保護管は、使用時に外側保護管内で激しく振動することになる。このため、異音が生じたり、場合によってはガスセンサ素子が破損する恐れがある。また、内側保護管の移動によりセンサのガス感受性や応答性に影響が出る恐れもある。つまり、従来のガスセンサは、保護管、特に内側保護管の耐振性が必ずしも良好とは言えなかった。 However, when such a gas sensor is subjected to a long period or large vibrations, the welded portion of the inner protective tube and the outer protective tube may break. Then, the inner protective tube vibrates violently in the outer protective tube during use. For this reason, there is a possibility that abnormal noise occurs or the gas sensor element is damaged in some cases. In addition, the movement of the inner protective tube may affect the gas sensitivity and responsiveness of the sensor. That is, the conventional gas sensor is not necessarily good in vibration resistance of the protective tube, particularly the inner protective tube.

本発明は、かかる現状に鑑みてなされたものであって、プロテクタの耐振性に優れたガスセンサを提供することを目的とする。 This invention is made | formed in view of this present condition, Comprising: It aims at providing the gas sensor excellent in the vibration resistance of a protector.

その解決手段は、軸方向に延びるガスセンサ素子と、前記ガスセンサ素子の先端部が自身の先端から突出した状態で、前記ガスセンサ素子の周囲を取り囲む筒状の主体金具と、前記主体金具に固定され、前記ガスセンサ素子の先端部を覆うプロテクタと、を備えるガスセンサであって、前記プロテクタは、前記主体金具に固定され、ガス導入窓を有する筒状の外側カバー部と、この外側カバー部よりも内側に配置された筒状の内側カバー部であって、軸方向に作用する押圧力によって弾性変形可能な弾性部を含む内側カバー部と、を備え、前記内側カバー部は、前記弾性部が前記軸方向の押圧力によって弾性変形した状態で、前記主体金具と前記外側カバー部との間で狭持されてなるガスセンサである。 The solution includes a gas sensor element extending in the axial direction, a cylindrical metal shell that surrounds the periphery of the gas sensor element in a state in which a tip portion of the gas sensor element protrudes from the tip of the gas sensor element, and is fixed to the metal shell. A protector that covers a front end portion of the gas sensor element, the protector being fixed to the metal shell and having a cylindrical outer cover portion having a gas introduction window, and an inner side of the outer cover portion. An inner cover portion including an elastic portion that is elastically deformable by a pressing force acting in an axial direction, and the inner cover portion includes an elastic portion that is in the axial direction. The gas sensor is sandwiched between the metal shell and the outer cover part in a state where it is elastically deformed by the pressing force of.

本発明によれば、内側カバー部は、軸方向に作用する押圧力によって弾性変形可能な弾性部を含む。そして、内側カバー部は、この弾性部が弾性変形した状態で、主体金具と外側カバー部との間で狭持されている。このため、このガスセンサでは、振動を受けても、内側カバー部が主体金具及び外側カバー部に当接した状態を保つため、ガスセンサに長期間あるいは大きな振動が加わった場合にも、外側カバー部内で内側カバー部が激しく振動することが防止される。
ここで、弾性部を含む内側カバー部は、上記の要件を満たすものであれば、いずれの形態とすることもできる。例えば、内側カバー部の先端側または後端側にバネ等からなる弾性部を設けてもよい。また、内側カバー部の軸方向中間にバネ等からなる弾性部を設けてもよい。また、後述するように、内側カバー部に弾性変形可能な鍔部を設けてもよい。 According to the present invention, the inner cover portion includes an elastic portion that can be elastically deformed by a pressing force acting in the axial direction. The inner cover portion is sandwiched between the metal shell and the outer cover portion in a state where the elastic portion is elastically deformed. For this reason, in this gas sensor, the inner cover remains in contact with the metal shell and the outer cover even when subjected to vibration. It is possible to prevent the inner cover portion from vibrating vigorously.
Here, the inner cover part including the elastic part may be in any form as long as it satisfies the above requirements. For example, you may provide the elastic part which consists of a spring etc. in the front end side or rear-end side of an inner side cover part. Moreover, you may provide the elastic part which consists of a spring etc. in the axial direction middle of an inner side cover part. Moreover, you may provide the collar part which can be elastically deformed in an inner side cover part so that it may mention later.

さらに、上記のガスセンサであって、前記内側カバー部は、前記ガスセンサ素子の先端部周囲を取り囲む内側筒状部を含み、前記弾性部は、前記内側筒状部から径方向外側に突出する鍔部であって、直接または間接に当接する前記主体金具によって軸方向先端側に押圧され、弾性変形を生じる鍔部を含むガスセンサとすると良い。 Further, in the above gas sensor, the inner cover portion includes an inner cylindrical portion surrounding the periphery of the tip portion of the gas sensor element, and the elastic portion protrudes radially outward from the inner cylindrical portion. And it is good to set it as the gas sensor containing the collar part which is pressed to the axial direction front end side by the said metal fitting which contact | abuts directly or indirectly, and produces elastic deformation.

本発明によれば、内側カバー部の弾性部は、内側筒状部から径方向外側に突出する鍔部を含む。そして、この鍔部が主体金具に押圧されて弾性変形している。このような構成とすることで、プロテクタの耐振性を向上させながらも、プロテクタを簡易な構造とすることができる。
なお、この鍔部は、内側筒状部と一体成形されていてもよいし、別体で形成されていてもよいが、成形面、コスト面の観点から一体成形の方が好ましい。 According to the present invention, the elastic portion of the inner cover portion includes a flange portion that protrudes radially outward from the inner cylindrical portion. And this collar part is pressed by the metal shell and is elastically deformed. With such a configuration, the protector can have a simple structure while improving the vibration resistance of the protector.
In addition, although this collar part may be integrally molded with the inner cylindrical part or may be formed as a separate body, integral molding is preferred from the viewpoint of molding surface and cost.

さらに、上記のガスセンサであって、前記鍔部は、周方向に断続的に配置されてなるガスセンサとすると良い。 Furthermore, in the gas sensor described above, the flange portion may be a gas sensor that is intermittently arranged in the circumferential direction.

本発明によれば、鍔部は、周方向に断続的に配置されている。このような構成とすることで、鍔部の弾性変形を有効に生じさせることができ、また、低コスト化に寄与することになる。 According to this invention, the collar part is arrange | positioned intermittently in the circumferential direction. By adopting such a configuration, elastic deformation of the collar portion can be effectively generated, and it contributes to cost reduction.

さらに、上記のいずれかに記載のガスセンサであって、前記内側カバー部は、前記鍔部の径方向外側端部から軸方向後端側に突出し、自身の後端が前記内側筒状部の後端より後端側に位置し、前記主体金具の先端が当接して軸方向先端側に押圧される脚部を含むガスセンサとすると良い。 Furthermore, in the gas sensor according to any one of the above, the inner cover portion protrudes from the radially outer end portion of the flange portion toward the axial rear end side, and the rear end of the inner cover portion is behind the inner cylindrical portion. The gas sensor may include a leg portion that is located on the rear end side from the end and that is pressed against the front end side in the axial direction by contacting the front end of the metal shell.

本発明によれば、主体金具と外側カバー部との間に狭持されて弾性変形し得る鍔部の径方向外側端部に、軸方向後端側に突出しつつ自身の後端が内側筒状部の後端より後端側に位置し、主体金具の先端が当接して軸方向先端側に押圧される脚部が設けられている。このような構成とすると、鍔部が脚部を介して主体金具に押圧される形態で弾性変形することになり、鍔部の弾性変形が安定して生じることになる。とりわけ、鍔部を上記のように周方向に断続的に配置した上で、この径方向外側端部に脚部を設けると、鍔部と主体金具の先端との間に空間（間隙）を形成することができるため、外側カバー部のガス導入窓から導入された被測定ガスを、鍔部鍔部同士の間を通じ、内側筒状部の後端を越えて、内側カバー部内に導入することができる。従って、プロテクタの耐振性を確保し、プロテクタの構造を簡易として、さらに、被測定ガスの流通経路をも容易に構成することができる。なお、鍔部から突出する脚部についても、内側筒状部、鍔部と共に一体成形されていることが、成形面、コスト面の観点から好ましい。 According to the present invention, the rear end of the flange portion which is sandwiched between the metal shell and the outer cover portion and protrudes toward the rear end side in the axial direction on the radially outer end portion of the collar portion which can be elastically deformed is an inner cylindrical shape. A leg portion is provided which is positioned on the rear end side from the rear end of the portion and is pressed against the front end side in the axial direction by abutting the front end of the metal shell. With such a configuration, the collar portion is elastically deformed in such a form that it is pressed against the metal shell via the leg portion, and the elastic deformation of the collar portion is stably generated. In particular, when the collar is intermittently arranged in the circumferential direction as described above and a leg is provided at the radially outer end, a space (gap) is formed between the collar and the front end of the metal shell. it is possible to, the measurement gas introduced from the gas introduction window of the outer cover portion, through between the adjacent flange portions the flange portion beyond the rear end of the inner cylindrical portion, to be introduced into the inner cover portion it can. Therefore, the vibration resistance of the protector can be ensured, the protector structure can be simplified, and the flow path of the gas to be measured can be easily configured. In addition, it is preferable from a viewpoint of a shaping | molding surface and a cost side that it is integrally molded with the inner cylindrical part and the collar part also about the leg part which protrudes from the collar part.

さらに、上記のいずれかに記載のガスセンサであって、前記外側カバー部と前記内側カバー部は、いずれかの部分において互いに固着されてなるガスセンサとすると良い。 Furthermore, the gas sensor according to any one of the above, wherein the outer cover portion and the inner cover portion are preferably fixed to each other at any portion.

本発明によれば、外側カバー部と内側カバー部は、いずれかの部分において互いに固着されてなる。このようにすることで、内側カバー部の耐振性をさらに向上させることができる。 According to the present invention, the outer cover portion and the inner cover portion are fixed to each other at any portion. By doing in this way, the vibration resistance of an inner side cover part can further be improved.

さらに、上記のガスセンサであって、前記外側カバー部は、前記主体金具に固定された外側筒状部と、この外側筒状部より先端側に位置し、外側先端通気孔を含む外側底部と、を有し、前記内側カバー部は、前記ガスセンサ素子の先端部周囲を取り囲む内側筒状部と、この内側筒状部より先端側に位置すると共に、前記外側先端通気孔と連通する内側先端通気孔を含む内側底部と、を有し、前記外側底部と前記内側底部とが互いに固着されてなるガスセンサとすると良い。 Further, in the above gas sensor, the outer cover part is an outer cylindrical part fixed to the metal shell, and an outer bottom part that is located on the distal side from the outer cylindrical part and includes an outer distal vent hole; The inner cover portion includes an inner cylindrical portion that surrounds the periphery of the distal end portion of the gas sensor element, and an inner distal end vent hole that is located on the distal end side from the inner cylindrical portion and communicates with the outer distal end vent hole. And a gas sensor in which the outer bottom portion and the inner bottom portion are fixed to each other.

このように外側先端通気孔を含む外側底部と内側先端通気孔を含む内側底部を固着することにより、外側カバー部と内側カバー部とを安定して固着することができ、内側カバー部の耐振性を一層向上させることができる。 By fixing the outer bottom portion including the outer tip vent hole and the inner bottom portion including the inner tip vent hole in this manner, the outer cover portion and the inner cover portion can be stably fixed, and the vibration resistance of the inner cover portion is ensured. Can be further improved.

また、他の解決手段は、軸方向に延びるガスセンサ素子と、前記ガスセンサ素子の先端部が自身の先端から突出した状態で、前記ガスセンサ素子の周囲を取り囲む筒状の主体金具と、前記主体金具に固定され、前記ガスセンサ素子の先端部を覆うプロテクタと、を備えるガスセンサであって、前記プロテクタは、前記主体金具に固定された筒状の外側カバー部であって、前記主体金具に固定され、ガス導入窓を有する外側筒状部、及び、この外側筒状部の先端側に位置し、外部と連通する外側先端通気孔を有する外側底部、を含む外側カバー部と、前記外側カバー部よりも内側に配置された筒状の内側カバー部であって、前記ガスセンサ素子の先端部周囲を取り囲む内側筒状部、この内側筒状部の先端側に位置し、前記外側カバー部の外側先端通気孔に連通する内側先端通気孔を有する内側底部、前記内側筒状部の後端から径方向外側に突出すると共に、周方向に断続的に配置され、軸方向に作用する押圧力によって弾性変形可能な鍔部、及び、この鍔部の径方向外側端部から軸方向後端側に突出する脚部、を含む内側カバー部と、を備え、前記主体金具の先端で、前記内側カバー部の脚部を軸方向先端側に押圧すると共に、前記外側カバー部の外側底部の少なくとも一部で、前記内側カバー部の内側底部の少なくとも一部を軸方向後端側に押圧して、前記鍔部を弾性変形させてなるガスセンサである。 In addition, another solution includes: a gas sensor element extending in the axial direction; a cylindrical metal shell surrounding the gas sensor element in a state where a tip portion of the gas sensor element protrudes from the tip of the gas sensor element; And a protector that covers the tip of the gas sensor element, the protector being a cylindrical outer cover fixed to the metal shell, fixed to the metal shell, and a gas sensor An outer cover portion including an outer cylindrical portion having an introduction window, and an outer bottom portion having an outer tip ventilation hole located on the distal end side of the outer cylindrical portion and communicating with the outside, and on the inner side of the outer cover portion A cylindrical inner cover portion disposed on the inner cylindrical portion surrounding the distal end portion of the gas sensor element, located on the distal end side of the inner cylindrical portion, and positioned on the outer side of the outer cover portion. Inner bottom portion having an inner tip ventilation hole communicating with the vent hole, the radially outwardly projecting from the rear end of the inner cylindrical portion is intermittently arranged in the circumferential direction, the elastic deformation by a pressing force acting in the axial direction possible flange portion, and provided with an inner cover portion including a leg portion, which protrudes from the radially outer end of the flange portion in the axial direction rear end side, the tip of the metal shell, the inner cover portion The leg portion is pressed toward the front end side in the axial direction, and at least a part of the inner bottom portion of the inner cover portion is pressed toward the rear end side in the axial direction with at least a portion of the outer bottom portion of the outer cover portion. Is a gas sensor that is elastically deformed.

本発明によれば、内側カバー部は、内側筒状部の後端から径方向外側に突出すると共に、周方向に断続的に配置され、軸方向に作用する押圧力によって弾性変形可能な鍔部と、この鍔部の径方向外側端部から軸方向後端側に突出する脚部とを含む。そして、主体金具の先端で、内側カバー部の脚部を軸方向先端側に押圧すると共に、外側カバー部の外側底部の少なくとも一部で、内側カバー部の内側底部の少なくとも一部を軸方向後端側に押圧して、鍔部を弾性変形させている。このため、このガスセンサでは、振動を受けても、内側カバー部が主体金具及び外側カバー部に当接した状態を保つため、外側カバー部内で内側カバー部が激しく振動することが防止される。その上、プロテクタの構造を簡易なものとすることができる。しかも、外側カバー部のガス導入窓から導入された被測定ガスを、鍔部同士の間を通じ、内側筒状部の後端を越えて、内側カバー部内に導入する流通経路も容易に構成できる。 According to the present invention, the inner cover portion is configured to protrude from the rear end of the inner cylindrical portion radially outward, are intermittently arranged in the circumferential direction, elastically deformable flange portion by the pressing force acting in the axial direction And leg portions projecting from the radially outer end portion of the flange portion toward the rear end side in the axial direction. Then, at the front end of the metal shell, the leg portion of the inner cover portion is pressed toward the front end in the axial direction, and at least a part of the inner bottom portion of the inner cover portion is rearward in the axial direction at least at the outer bottom portion of the outer cover portion. The collar is elastically deformed by pressing toward the end side. For this reason, in this gas sensor, even if it receives vibration, the inner cover portion is kept in contact with the metal shell and the outer cover portion, so that the inner cover portion is prevented from vigorously vibrating in the outer cover portion. In addition, the structure of the protector can be simplified. Moreover, the measurement gas introduced from the gas introduction window of the outer cover portion, through between the adjacent flange portion beyond the rear end of the inner cylindrical portion, the distribution channel to be introduced into the inner cover portion can be easily configured.

以下、本発明の実施の形態を、図面を参照しつつ説明する。
本実施形態に係るガスセンサ１０１の断面図を図１に、要部の平面図を図２に、要部の断面図を図３に示す。また、プロテクタ１５１について図４に示す。なお、図１〜図４においては、下方が先端側、上方が後端側となる。このガスセンサ１０１は、内燃機関の排ガス管に取り付けて、排気ガス中の酸素濃度を測定する酸素センサである。ガスセンサ１０１は、軸線Ｃ方向に延びるガスセンサ素子１０３と、このガスセンサ素子１０３の周囲を取り囲む筒状の主体金具１２１と、ガスセンサ素子１０３のうちで排ガスに晒される先端部１０５を覆うプロテクタ１５１とを備える。 Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view of a gas sensor 101 according to the present embodiment, FIG. 2 is a plan view of the main part, and FIG. 3 is a cross-sectional view of the main part. Further, the protector 151 is shown in FIG. 1 to 4, the lower side is the front end side, and the upper side is the rear end side. The gas sensor 101 is an oxygen sensor that is attached to an exhaust gas pipe of an internal combustion engine and measures the oxygen concentration in the exhaust gas. The gas sensor 101 includes a gas sensor element 103 that extends in the direction of the axis C, a cylindrical metal shell 121 that surrounds the periphery of the gas sensor element 103, and a protector 151 that covers the tip 105 of the gas sensor element 103 that is exposed to exhaust gas. .

このうち、ガスセンサ素子１０３は、感ガス特性を有すると共に、先端１０５Ｓが閉じた有底筒状をなし、被測定ガス中の酸素濃度を測定可能なガス検出部１０７を有する。また、このガス検出部１０７の内側には、ガス検出部１０７を加熱するための棒状のヒータ１０９が挿設されている。また、ガスセンサ素子１０３は、軸方向の中央付近に、径方向外側に突出する突出部１１１を有する。この突出部１１１は、後述するように、このガスセンサ素子１０３を主体金具１２１に保持するために利用されている。 Among these, the gas sensor element 103 has a gas sensing part 107 having a gas sensing characteristic, a bottomed cylindrical shape with a closed tip 105S, and capable of measuring the oxygen concentration in the gas to be measured. Further, a rod-shaped heater 109 for heating the gas detection unit 107 is inserted inside the gas detection unit 107. Further, the gas sensor element 103 has a protruding portion 111 that protrudes radially outward near the center in the axial direction. As will be described later, the protrusion 111 is used to hold the gas sensor element 103 on the metal shell 121.

主体金具１２１は、プロテクタ１５１内に挿入される比較的肉薄な先端部１２３を有する。また、主体金具１２１の内周には、先端部１２３よりも後端側の位置に、ガスセンサ素子１０３を軸方向に保持（支持）するための支持面を有する支持部１２５が設けられている。さらに、支持部１２５よりも後端側にも段付部１２７が形成されている。一方、主体金具１２１の外周には、先端部１２３よりも後端側の位置に、このガスセンサ１０１を排ガス管に取り付けるため周方向に取付ねじ部１２９が設けられている。また、この取付ねじ部１２９の後端側には、このガスセンサ１０１を排ガス管に取り付ける際に利用される六角フランジ部１３１（工具係合部）が設けられている。 The metal shell 121 has a relatively thin tip 123 that is inserted into the protector 151. A support portion 125 having a support surface for holding (supporting) the gas sensor element 103 in the axial direction is provided on the inner periphery of the metal shell 121 at a position on the rear end side with respect to the front end portion 123. Further, a stepped portion 127 is also formed on the rear end side of the support portion 125. On the other hand, on the outer periphery of the metal shell 121, a mounting screw portion 129 is provided in the circumferential direction in order to attach the gas sensor 101 to the exhaust gas pipe at a position closer to the rear end side than the front end portion 123. Further, a hexagonal flange portion 131 (tool engaging portion) used when the gas sensor 101 is attached to the exhaust gas pipe is provided on the rear end side of the attachment screw portion 129.

この主体金具１２１は、ガスセンサ素子１０３の先端部１０５が自身の先端面１２３Ｓから突出した状態で、ガスセンサ素子１０３を同軸状に保持している。具体的には、主体金具１２１の支持部１２５上には、第１板パッキン１３３が配置されている。さらに、その上には、内周に段付部１３６を有する筒状の第１固定部材１３５が配置されている。ガスセンサ素子１０３は、この第１固定部材１３５に挿通され、ガスセンサ素子１０３の突出部１１１が、第２板パッキン１３７を介して、第１固定部材１３５の段付部１３６に係合している。第１固定部材１３５の後端側には、ガスセンサ素子１０３の外周面と主体金具１２１の内周面とによって構成される間隙に、粉末が充填されてなる充填封止層１３９が形成されている。さらに、この充填封止層１３９の後端側には、外周に段付部１４２を有し、内側をガスセンサ素子１０３が貫通する筒状の第２固定部材１４１が配置されている。第２固定部材１４１の後端側には、加締めリング１４５が配置され、主体金具１２１の後端部１３２によって加締められている。 The metal shell 121 holds the gas sensor element 103 coaxially in a state in which the distal end portion 105 of the gas sensor element 103 protrudes from its distal end surface 123S. Specifically, the first plate packing 133 is disposed on the support portion 125 of the metal shell 121. Further, a cylindrical first fixing member 135 having a stepped portion 136 on the inner periphery is disposed thereon. The gas sensor element 103 is inserted into the first fixing member 135, and the protruding portion 111 of the gas sensor element 103 is engaged with the stepped portion 136 of the first fixing member 135 via the second plate packing 137. On the rear end side of the first fixing member 135, a filling sealing layer 139 is formed in which a gap formed by the outer peripheral surface of the gas sensor element 103 and the inner peripheral surface of the metal shell 121 is filled with powder. . Further, on the rear end side of the filling and sealing layer 139, a cylindrical second fixing member 141 having a stepped portion 142 on the outer periphery and through which the gas sensor element 103 passes is arranged. A caulking ring 145 is disposed on the rear end side of the second fixing member 141 and is caulked by the rear end portion 132 of the metal shell 121.

プロテクタ１５１は、ガスセンサ素子１０３の先端部１０５を間隙を介して覆う筒状の内側カバー部１５３と、この内側カバー部１５３の外周に配置された筒状の外側カバー部１７３とを有する二重構造をなす。
このうち、外側カバー部１７３は、肉厚約０．５ｍｍの金属材からなり、円筒状の外側筒状部１７５（外径約１３．１ｍｍ）と、この先端側に位置する外側底部１７７とからなる。外側筒状部１７５には、被測定ガスを外部から外側カバー部１７５の内側に導入可能な外側ガス導入窓１７６が８カ所に設けられている。外側ガス導入窓１７６は、それぞれ長円形状をなし、各々の外側ガス導入窓１７６は、軸方向に見て中央よりも先端側の位置に、周方向に均等な間隔で形成されている。外側底部１７７には、その中央に、プロテクタ１５１よりも先端方向外部に連通する円形状の外側先端通気孔１７９が設けられている。 The protector 151 has a double structure having a cylindrical inner cover portion 153 that covers the distal end portion 105 of the gas sensor element 103 with a gap, and a cylindrical outer cover portion 173 disposed on the outer periphery of the inner cover portion 153. Make.
Of these, the outer cover portion 173 is made of a metal material having a thickness of about 0.5 mm, and includes a cylindrical outer cylindrical portion 175 (outer diameter of about 13.1 mm) and an outer bottom portion 177 located on the tip side. Become. The outer cylindrical portion 175 is provided with eight outer gas introduction windows 176 through which the gas to be measured can be introduced into the outer cover portion 175 from the outside. The outer gas introduction windows 176 each have an oval shape, and the outer gas introduction windows 176 are formed at equal intervals in the circumferential direction at positions closer to the tip than the center when viewed in the axial direction. The outer bottom portion 177 is provided with a circular outer front end vent hole 179 communicating with the outside in the front end direction with respect to the protector 151 at the center thereof.

内側カバー部１５３は、肉厚約０．３ｍｍの金属材からなり、円筒状の内側筒状部１５５（外径約８．５ｍｍ）と、この先端側に位置する内側底部１５７とを有する。内側筒状部１５５は、上記外側筒状部１７５と異なり、通気孔を有しない。一方、内側底部１５７には、その中央に、外側先端貫通孔１７９に連通し、プロテクタ１５１よりも先端方向外部に繋がる円形状の内側先端通気孔１５９が設けられている。 The inner cover portion 153 is made of a metal material having a thickness of about 0.3 mm, and has a cylindrical inner cylindrical portion 155 (outer diameter: about 8.5 mm) and an inner bottom portion 157 located on the tip side. Unlike the outer cylindrical portion 175, the inner cylindrical portion 155 does not have a vent hole. On the other hand, the inner bottom portion 157 is provided with a circular inner tip vent hole 159 communicating with the outer tip through-hole 179 and connected to the outside in the tip direction with respect to the protector 151 at the center thereof.

また、内側カバー部１５３は、内側筒状部１５５の後端１５５Ｋから６カ所で径方向外側に突出すると共に、周方向に断続的に配置された鍔部１８３（弾性部１８１）を有する。後述するように、この鍔部１８３は、軸方向に作用する押圧力によって屈曲するようにして弾性変形可能である。また、鍔部１８３の径方向外側端部には、それぞれ軸方向後端側に突出する脚部１８５が設けられている。なお、外側ガス導入窓１７６の開口面積に対する鍔部１８３（弾性変形した状態の鍔部１８３）の軸方向先端側から投影した投影面積の割合は、５％〜４０％の範囲内であればよく、本実施形態では、約２２％とされている。 The inner cover portion 153 has flanges 183 (elastic portions 181) that protrude radially outward from the rear end 155K of the inner cylindrical portion 155 at six locations and are intermittently disposed in the circumferential direction. As will be described later, the flange 183 can be elastically deformed so as to be bent by the pressing force acting in the axial direction. In addition, a leg portion 185 that protrudes toward the rear end side in the axial direction is provided at the radially outer end portion of the flange portion 183. In addition, the ratio of the projected area projected from the axial front end side of the flange portion 183 (elastically deformed flange portion 183) to the opening area of the outer gas introduction window 176 may be within a range of 5% to 40%. In this embodiment, it is about 22%.

内側カバー部１５３と外側カバー部１７３は、内側底部１５７と外側底部１７７が、内側先端通気孔１５９の周囲部１５７Ｗと外側先端通気孔１７９の周囲部１７７Ｗにおいて、４カ所で部分的にスポット溶接されることにより互いに固着されている。これにより、内側先端通気孔１５９と外側先端通気孔１７９とが連通している。また、内側筒状部１５５と外側筒状部１７５は、外側ガス導入窓１７６と対向する位置に、内側筒状部１５５の側壁が存在し、内側筒状部１５５と外側筒状部１７５とが、平行となる形態とされている。なお、４カ所の溶接部を除く内側底部１５７と外側底部１７７との間には、約０．１ｍｍの隙間を生じている。 The inner cover portion 153 and the outer cover portion 173 are partially spot-welded at four locations on the inner bottom portion 157 and the outer bottom portion 177 at the peripheral portion 157W of the inner tip vent hole 159 and the peripheral portion 177W of the outer tip vent hole 179. Are fixed to each other. Thereby, the inner end vent hole 159 and the outer end vent hole 179 communicate with each other. In addition, the inner cylindrical portion 155 and the outer cylindrical portion 175 have a side wall of the inner cylindrical portion 155 at a position facing the outer gas introduction window 176, and the inner cylindrical portion 155 and the outer cylindrical portion 175 are separated from each other. , Parallel form. A gap of about 0.1 mm is generated between the inner bottom portion 157 and the outer bottom portion 177 except for the four welded portions.

このようなプロテクタ１５１は、外側カバー部１７３の後端部１８０（外側筒状部１７５の後端部）が、主体金具１２１の先端部１２３の外周面１２３Ｅにレーザ溶接され固着されている。また、内側カバー部１５３は、鍔部１８３（弾性部１８１）が軸方向の押圧力によって弾性変形した状態で、主体金具１２１と外側カバー部１７３との間で狭持されている。具体的には、主体金具１２１の先端部１２３（先端面１２３Ｓ）が、内側カバー部１５３の脚部１８５を軸方向先端側に押圧すると共に、外側カバー部１７３の外側底部１７７が、内側カバー部１５３の内側底部１５７を軸方向後端側に押圧している。このため、鍔部１８３が屈曲弾性変形している。 In such a protector 151, the rear end portion 180 (rear end portion of the outer cylindrical portion 175) of the outer cover portion 173 is fixed to the outer peripheral surface 123 </ b> E of the front end portion 123 of the metal shell 121 by laser welding. The inner cover portion 153 is sandwiched between the metal shell 121 and the outer cover portion 173 in a state where the flange portion 183 (elastic portion 181) is elastically deformed by the axial pressing force. Specifically, the distal end portion 123 (the distal end surface 123S) of the metal shell 121 presses the leg portion 185 of the inner cover portion 153 toward the axial distal end side, and the outer bottom portion 177 of the outer cover portion 173 is the inner cover portion. The inner bottom portion 157 of 153 is pressed toward the rear end side in the axial direction. For this reason, the collar part 183 is flexibly elastically deformed.

また、主体金具１２１の先端部１２３と、外側筒状部１７５と、内側筒状部１５５とは、外側ガス導入窓１７６から導入された被測定ガスを、内側カバー部１５３とガスセンサ素子１０３の先端部１０５との間の空隙に導く内側ガス導入路１９１を構成している。本実施形態では、内側筒状部１５５の後端１５５Ｋに径方向外側に突出する鍔部１８３を設け、さらに、鍔部１８３の径方向外側端部に、軸方向後端側に突出し、自身の後端（後端面）に主体金具１２１の先端面１２３Ｓが当接する脚部１８５を設けることにより、鍔部１８３と主体金具１２１との間をあけ、内側ガス導通路１９１を構成している。従って、この内側ガス導入路１９１は、外側ガス導入窓１７６から導入された被測定ガスを、外側筒状部１７５と内側筒状部１５５との間を通過させ、後端側に導く。その後、被測定ガスを、鍔部１８３の間を通過させて、主体金具１２１の先端部１２３のうち、内周面１２３Ｄと外周面１２３Ｅとの間を結ぶ連結面（先端面）１２３Ｓの内周面側端縁１２３ＳＴよりも軸方向に見て先端側で、内側筒状部１５５の後端１５５Ｋを越えさせる。そして、被測定ガスを、内側カバー部１５３とガスセンサ素子１０３の先端部１０５との間の空隙に導き、内側先端通気孔１５９及び外側先端通気孔１７９を介してプロテクタ１５１の外部に排出する。
なお、本実施形態において、主体金具１２１の先端部１２３の内周面端縁１２３Ｔと内側筒状部１５５の後端１５５Ｋとの距離ｄは約０．８ｍｍ、内側筒状部１５５の後端１５５Ｋと外側ガス導入窓１７６の後端側縁１７６Ｋとの軸方向についての最短距離Ｄは約５．１ｍｍとされている。 Further, the distal end portion 123 of the metal shell 121, the outer cylindrical portion 175, and the inner cylindrical portion 155 pass the measurement gas introduced from the outer gas introduction window 176 into the distal ends of the inner cover portion 153 and the gas sensor element 103. An inner gas introduction path 191 that leads to a gap between the portion 105 and the portion 105 is configured. In the present embodiment, a flange 183 that protrudes radially outward is provided at the rear end 155K of the inner cylindrical portion 155, and further, protrudes toward the rear end side in the axial direction at the radially outer end of the flange 183. By providing a leg portion 185 with which the front end surface 123S of the metal shell 121 abuts at the rear end (rear end surface), a gap is formed between the flange 183 and the metal shell 121, thereby forming an inner gas conduction path 191. Therefore, the inner gas introduction path 191 passes the gas to be measured introduced from the outer gas introduction window 176 between the outer cylindrical portion 175 and the inner cylindrical portion 155 and guides it to the rear end side. Thereafter, the gas to be measured is passed between the flanges 183, and the inner periphery of the connecting surface (tip surface) 123S connecting the inner peripheral surface 123D and the outer peripheral surface 123E in the front end portion 123 of the metal shell 121. The rear end 155 </ b> K of the inner cylindrical portion 155 is exceeded on the front end side as viewed in the axial direction from the surface side edge 123 </ b> ST. Then, the gas to be measured is guided to the gap between the inner cover portion 153 and the distal end portion 105 of the gas sensor element 103, and discharged to the outside of the protector 151 through the inner distal end vent hole 159 and the outer distal end vent hole 179.
In this embodiment, the distance d between the inner peripheral surface edge 123T of the front end portion 123 of the metal shell 121 and the rear end 155K of the inner cylindrical portion 155 is about 0.8 mm, and the rear end 155K of the inner cylindrical portion 155. And the rear end side edge 176K of the outer gas introduction window 176 in the axial direction is about 5.1 mm.

図１に示すように、主体金具１２１のうち、六角フランジ部１３１の後端側には、筒状の金属外筒２０１の先端部２０１Ｓが外側からレーザ溶接により固着されている。また、金属外筒２０１の後端側開口部２０１Ｋには、ゴム等で構成されたグロメット２０３が嵌入され、加締めにより封止されている。グロメット２０３の中心部には、大気を金属外筒２０１内に導入する一方、水分の侵入を防ぐフィルタ部材２０５が配置されている。また、グロメット２０３の先端側には、絶縁性のアルミナセラミックからなるセパレータ２０７が設けられている。そして、グロメット２０３及びセパレータ２０７を貫通してセンサ出力リード線２１１，２１２及びヒータリード線２１３，２１４が配置されている。また、セパレータ２０７内には、第１，第２センサ端子金具２１５，２１６のコネクタ部２１５Ｂ，２１５Ｃ、及び、ヒータ端子金具２１７，２１８が互いに絶縁されつつ保持されている。 As shown in FIG. 1, a front end portion 201 </ b> S of a cylindrical metal outer cylinder 201 is fixed to the rear end side of the hexagon flange portion 131 of the metal shell 121 from the outside by laser welding. A grommet 203 made of rubber or the like is fitted into the rear end side opening 201K of the metal outer cylinder 201 and sealed by caulking. At the center of the grommet 203, a filter member 205 that introduces air into the metal outer cylinder 201 and prevents moisture from entering is disposed. Further, a separator 207 made of insulating alumina ceramic is provided on the front end side of the grommet 203. Then, sensor output lead wires 211 and 212 and heater lead wires 213 and 214 are disposed through the grommet 203 and the separator 207. In the separator 207, the connector portions 215B and 215C of the first and second sensor terminal fittings 215 and 216 and the heater terminal fittings 217 and 218 are held while being insulated from each other.

第１センサ端子金具２１５は、そのコネクタ部２１５Ｂがセンサ出力リード線２１１を把持してこれに電気的に接続すると共に、挿入部２１５Ｃがガス検出部１０７の有抵孔内に挿入され、センサ内部電極層と電気的に接続している。また、第２センサ端子金具２１６は、そのコネクタ部２１６Ｂがセンサ出力リード線２１２を把持してこれに電気的に接続すると共に、把持部２１６Ｃがガスセンサ部１０７の後端付近の外周を把持して、センサ外部電極層と電気的に接続している。また、ヒータ端子金具２１７，２１８は、ヒータリード線２１３，２１４とそれぞれ電気的に接続すると共に、ヒータ部１０９の電極パッド１０９Ｂ，１０９Ｃとそれぞれ電気的に接続している。 The first sensor terminal fitting 215 includes a connector portion 215B that grips and electrically connects the sensor output lead wire 211, and an insertion portion 215C that is inserted into the tangential hole of the gas detection portion 107, It is electrically connected to the electrode layer. The second sensor terminal fitting 216 has a connector portion 216B that grips and electrically connects to the sensor output lead 212, and a grip portion 216C that grips the outer periphery near the rear end of the gas sensor portion 107. The sensor external electrode layer is electrically connected. The heater terminal fittings 217 and 218 are electrically connected to the heater lead wires 213 and 214, respectively, and are also electrically connected to the electrode pads 109B and 109C of the heater section 109, respectively.

このようなガスセンサ１０１は、長期間にわたる振動を受けても、内側カバー部１５３が主体金具１２１の先端面１２３Ｓと外側カバー部１７３の外側底部１７７との間で狭持された状態を保つため、外側カバー部１７３内で内側カバー部１５３が激しく振動することが防止される。その上、弾性部１８１を上述したような鍔部１８３としているため、プロテクタ１５１の耐振性を向上させながらも、プロテクタ１５１を簡易な構造とすることができる。さらに、鍔部１８３に脚部１８５を設けているため、被測定ガスを、鍔部１８３同士の間を通じ、内側筒状部１５５の後端１５５Ｋを越えて、内側カバー部１５５内に導入する流通経路（内側ガス導入路１９１）も容易に構成できる。また、外側カバー部１７３と内側カバー部１５３は、先端側において溶接しているため、プロテクタ１５１の耐振性をさらに向上させることができる。 Even if such a gas sensor 101 is subjected to vibration for a long period of time, the inner cover portion 153 maintains a state of being sandwiched between the front end surface 123S of the metal shell 121 and the outer bottom portion 177 of the outer cover portion 173. It is possible to prevent the inner cover portion 153 from vigorously vibrating in the outer cover portion 173. In addition, since the elastic portion 181 is the flange portion 183 as described above, the protector 151 can have a simple structure while improving the vibration resistance of the protector 151. Further, since the leg portion 185 is provided in the flange portion 183, the gas to be measured is introduced into the inner cover portion 155 through the gap between the flange portions 183 and beyond the rear end 155K of the inner cylindrical portion 155. The path (inner gas introduction path 191) can also be easily configured. Moreover, since the outer cover part 173 and the inner cover part 153 are welded on the distal end side, the vibration resistance of the protector 151 can be further improved.

なお、このガスセンサ１０１は、公知の手法により製造することができる。このうち、プロテクタ１５１は、内側筒状部１５５、内側底部１５７、鍔部１８３及び脚部１８５を有する内側カバー部１５３と、外側筒状部１７５及び外側底部１７７を有する外側カバー部１７３とを別々に成形した後、先端側を溶接により固着すればよい。そして、この両者１５３，１７３を固着させた状態で、内側カバー部１５３の脚部１８５の後端に主体金具１２１の先端面１２３Ｓを当てて鍔部１８３を弾性変形させつつ、外側カバー部１７３の後端部１８０を主体金具１２１の先端部１２３の所定位置において溶接すればよい。 The gas sensor 101 can be manufactured by a known method. Among these, the protector 151 includes an inner cover part 153 having an inner cylindrical part 155, an inner bottom part 157, a flange part 183 and a leg part 185, and an outer cover part 173 having an outer cylindrical part 175 and an outer bottom part 177. After forming, the tip side may be fixed by welding. Then, with the both 153 and 173 fixed, the front end surface 123S of the metal shell 121 is applied to the rear end of the leg portion 185 of the inner cover portion 153 to elastically deform the flange portion 183, while the outer cover portion 173 is elastically deformed. What is necessary is just to weld the rear-end part 180 in the predetermined position of the front-end | tip part 123 of the metal shell 121. FIG.

以上において、本発明を実施形態に即して説明したが、本発明は上述の実施形態に限定されるものではなく、その要旨を逸脱しない範囲で、適宜変更して適用できることはいうまでもない。
例えば、上記実施形態では、鍔部１８３に脚部１８５を設け、この脚部１８５に主体金具１２１を当接させている。即ち、主体金具１２１は、弾性部１８１である鍔部１８３に間接的に当接している。しかし、脚部１８５をなくして、主体金具１２１を鍔部１８３に直接当接させるようにしてもよい。このような場合、上述した内側ガス導入路１９１を構成しにくくなるので、内側筒状部１５５の側壁にガス導入窓を設けるようにするとよい。
また、上記実施形態では、内側筒状部１５５の後端１５５Ｋから鍔部１８３が突出した形態としているが、例えば、内側筒状部１５５の軸方向中間部から鍔部１８３が突出するような形態とすることもできる。 In the above, the present invention has been described with reference to the embodiment. However, the present invention is not limited to the above-described embodiment, and it is needless to say that the present invention can be appropriately modified and applied without departing from the gist thereof. .
For example, in the above-described embodiment, the leg portion 183 is provided with the leg portion 185, and the metal shell 121 is brought into contact with the leg portion 185. That is, the metal shell 121 is in indirect contact with the flange portion 183 that is the elastic portion 181. However, the leg portion 185 may be eliminated and the metal shell 121 may be brought into direct contact with the flange portion 183. In such a case, it is difficult to configure the above-described inner gas introduction path 191, so it is preferable to provide a gas introduction window on the side wall of the inner cylindrical portion 155.
Moreover, in the said embodiment, it is set as the form which the collar part 183 protruded from the rear end 155K of the inner cylindrical part 155, For example, the form which the collar part 183 protrudes from the axial direction intermediate part of the inner cylindrical part 155 It can also be.

また、上記実施形態では、有底筒状の形態をなすガスセンサ素子１０３を例示した。しかし、ガスセンサ素子の形態は、板状などとすることもできる。
また、上記実施形態では、外側ガス導入窓１７６の形状を長円形、内側先端通気孔１５９及び外側先端通気孔１７９の形状を円形としている。しかし、これらの孔の形状は、楕円形、矩形など適宜変更することができる。
また、上記実施形態では、鍔部１８３は、６カ所で径方向外側に突出する形態としているが、鍔部の数や形状はこれに限定されるものではなく、適宜変更することができる。 Moreover, in the said embodiment, the gas sensor element 103 which makes a bottomed cylindrical form was illustrated. However, the form of the gas sensor element may be a plate shape.
In the above embodiment, the outer gas introduction window 176 has an oval shape, and the inner tip vent hole 159 and the outer tip vent hole 179 have a circular shape. However, the shape of these holes can be changed as appropriate, such as an oval or a rectangle.
Moreover, in the said embodiment, although the collar part 183 is set as the form which protrudes to a radial direction outer side in six places, the number and shape of a collar part are not limited to this, It can change suitably.

実施形態に係るガスセンサの断面図である。It is sectional drawing of the gas sensor which concerns on embodiment. 実施形態に係るガスセンサの要部の平面図である。It is a top view of the principal part of the gas sensor concerning an embodiment. 実施形態に係るガスセンサの要部の断面図である。It is sectional drawing of the principal part of the gas sensor which concerns on embodiment. 実施形態に係るガスセンサのうちプロテクタを示す説明図である。It is explanatory drawing which shows a protector among the gas sensors which concern on embodiment.

１０１ガスセンサ
１０３ガスセンサ素子
１０５（ガスセンサ素子の）先端部
１２１主体金具
１２３（主体金具の）先端部
１５１プロテクタ
１５３内側カバー部
１５５内側筒状部
１５９内側先端通気孔
１７３外側カバー部
１７５外側筒状部
１７６外側ガス導入窓
１７９外側先端通気孔
１８１弾性部
１８３鍔部
１８５脚部
１９１内側ガス導入路 101 Gas sensor 103 Gas sensor element 105 (gas sensor element) tip 121 metal shell 123 (metal shell) tip 151 protector 153 inner cover 155 inner cylindrical portion 159 inner tip vent 173 outer cover 175 outer cylindrical portion 176 Outer gas introduction window 179 Outer tip vent hole 181 Elastic portion 183 flange portion 185 Leg portion 191 Inner gas introduction path

Claims

A gas sensor element extending in the axial direction;
With the tip of the gas sensor element protruding from its tip, a cylindrical metal shell surrounding the gas sensor element,
A protector that is fixed to the metal shell and covers a tip of the gas sensor element,
The protector is
A cylindrical outer cover portion fixed to the metal shell and having a gas introduction window;
A cylindrical inner cover part disposed inside the outer cover part, the inner cover part including an elastic part that can be elastically deformed by a pressing force acting in the axial direction;
With
The inner cover portion is a gas sensor that is sandwiched between the metallic shell and the outer cover portion in a state where the elastic portion is elastically deformed by the axial pressing force.

The gas sensor according to claim 1,
The inner cover portion includes an inner cylindrical portion surrounding the periphery of the tip portion of the gas sensor element,
The elastic part is a flange that protrudes radially outward from the inner cylindrical portion, and includes a flange that is elastically deformed by being pressed toward the distal end in the axial direction by the metal shell that directly or indirectly abuts. .

The gas sensor according to claim 2,
The gas sensor is a gas sensor that is intermittently disposed in the circumferential direction.

The gas sensor according to claim 2 or 3, wherein
The inner cover part protrudes from the radially outer end of the flange part toward the rear end side in the axial direction, and the rear end of the inner cover part is located closer to the rear end side than the rear end of the inner cylindrical part. A gas sensor including a leg portion that comes into contact with and is pressed toward the front end in the axial direction.

It is a gas sensor as described in any one of Claims 1-4, Comprising:
The gas sensor in which the outer cover portion and the inner cover portion are fixed to each other at any portion.

The gas sensor according to claim 5,
The outer cover portion is
An outer cylindrical portion fixed to the metal shell,
An outer bottom located on the tip side from the outer cylindrical portion, including the outer tip vent hole,
Have
The inner cover portion is
An inner cylindrical part surrounding the periphery of the tip of the gas sensor element;
An inner bottom portion including an inner tip vent hole that is located on the tip side from the inner cylindrical portion and communicates with the outer tip vent hole;
Have
A gas sensor in which the outer bottom portion and the inner bottom portion are fixed to each other.

A gas sensor element extending in the axial direction;
With the tip of the gas sensor element protruding from its tip, a cylindrical metal shell surrounding the gas sensor element,
A protector that is fixed to the metal shell and covers a tip of the gas sensor element,
The protector is
A cylindrical outer cover portion fixed to the metal shell,
An outer cylindrical portion fixed to the metal shell and having a gas introduction window; and
An outer bottom portion that is located on the distal end side of the outer cylindrical portion and has an outer distal end vent hole communicating with the outside,
Including an outer cover part,
A cylindrical inner cover portion disposed inside the outer cover portion,
An inner cylindrical part surrounding the periphery of the tip of the gas sensor element;
An inner bottom portion having an inner tip vent hole located on the tip end side of the inner cylindrical portion and communicating with the outer tip vent hole of the outer cover portion,
With radially outwardly projecting from the rear end of the inner cylindrical portion is intermittently arranged in the circumferential direction, elastically deformable flange portion by the pressing force acting in the axial direction, and,
Legs projecting from the radially outer end of the flange portion in the axial direction rear end side,
Including an inner cover part,
With
At the front end of the metal shell, the leg of the inner cover part is pressed toward the front end in the axial direction,
At least part of the outer bottom part of the outer cover part, pressing at least part of the inner bottom part of the inner cover part toward the rear end side in the axial direction,
A gas sensor obtained by elastically deforming the collar portion .