JP2013181768A

JP2013181768A - Gas sensor

Info

Publication number: JP2013181768A
Application number: JP2012044020A
Authority: JP
Inventors: Takehiro Oba; 健弘大場; Shingo Ito; 慎悟伊藤; Yuichi Yamada; 裕一山田; Daisuke Tahira; 大輔多比良; Hiroya Furuta; 紘也古田
Original assignee: NGK Spark Plug Co Ltd
Current assignee: Niterra Co Ltd
Priority date: 2012-02-29
Filing date: 2012-02-29
Publication date: 2013-09-12
Anticipated expiration: 2032-02-29
Also published as: CN103293206A; CN103293206B; JP5509234B2

Abstract

PROBLEM TO BE SOLVED: To provide a gas sensor in which an electrode pad of a sensor element can reliably be connected to terminal metal fittings in accordance with narrowness of the sensor element while securing the strength and spring property of the terminal metal fittings themselves.SOLUTION: In a gas sensor 200 provided with a sensor element 10 formed in the shape of a plate extending in an axis O direction to have facing principal planes 10A and 10B, and having a plurality of electrode pads 11a, 11b, 12a and 12b arranged in a width direction at a rear end side of at least one of the principal planes, and terminal metal fittings 21a, 21b, 22a and 22b respectively connected to the electrode pads, the minimum distance G, Gobtained by mutually connecting center lines Ce going through centers in a width direction of outer terminal metal fittings respectively connected to two electrode pads is wider than the maximum intervals Gand Gbetween two outer edges being the most separate among the plurality of electrode pads in the width direction of the principal planes, the outer terminal fittings have inner protrusion parts 21p1 and 22p1 and outer protrusion parts 21p2 and 22p2, and peaks of the inner protrusion parts are connected to the two electrode pads.

Description

本発明は、被検出ガスの濃度を検出するセンサ素子を備えたガスセンサに関する。 The present invention relates to a gas sensor including a sensor element that detects the concentration of a gas to be detected.

自動車等の排気ガス中の酸素やＮＯ_ｘの濃度を検出するガスセンサとして、固体電解質を用いた板状のセンサ素子を有するものが知られている。
この種のガスセンサとして、板状のセンサ素子の対向する主面の後端側に幅方向に並ぶ複数の電極パッドを設け、この電極パッドのそれぞれに端子金具を電気的に接触させてセンサ素子からのセンサ出力信号を外部に取り出すものが広く用いられている。そして、端子金具と電極パッドとの電気的な接続信頼性を向上させるため、端子金具に突起部を１個設け、この突起部の頂部を電極パッドに点接触させる技術が知られている（特許文献１、２）。
例えば、特許文献２記載のガスセンサの場合、図１０に示すように、センサ素子１０の一方の主面１０Ａに幅方向に２つの電極パッド１１ａ、１１ｂが並び、これら電極パッド１１ａ、１１ｂに対向して２つの端子金具２１０ａ、２１０ｂがセラミック製のセパレータ１６６内に配置されている。そして、各端子金具２１０ａ、２１０ｂのそれぞれに設けられた突起部２１０ｐが、電極パッド１１ａ、１１ｂにそれぞれ点接触している。
同様に、センサ素子１０の他方の主面１０Ｂにも幅方向に２つの電極パッド１２ａ、１２ｂが並び、これら電極パッド１２ａ、１２ｂに対向して２つの端子金具２２０ａ、２２０ｂが配置されている。そして、各端子金具２２０ａ、２２０ｂのそれぞれに設けられた突起部２２０ｐが、電極パッド１２ａ、１２ｂにそれぞれ点接触している。 As gas sensor for detecting the concentration of oxygen and NO _x in the exhaust gas of an automobile, having a plate-shaped sensor element using a solid electrolyte it is known.
As this type of gas sensor, a plurality of electrode pads arranged in the width direction are provided on the rear end side of the opposing main surface of the plate-like sensor element, and a terminal fitting is electrically contacted with each of the electrode pads to remove the sensor element from the sensor element. A sensor output signal is widely used. And in order to improve the electrical connection reliability of a terminal metal fitting and an electrode pad, the technique which provides one projection part in a terminal metal fitting and makes the top part of this projection part point-contact with an electrode pad (patent) References 1, 2).
For example, in the case of the gas sensor described in Patent Document 2, as shown in FIG. 10, two electrode pads 11a and 11b are arranged in the width direction on one main surface 10A of the sensor element 10, and face the electrode pads 11a and 11b. The two terminal fittings 210a and 210b are disposed in a ceramic separator 166. And the protrusion part 210p provided in each of each terminal metal fitting 210a, 210b is respectively in point contact with electrode pad 11a, 11b.
Similarly, two electrode pads 12a and 12b are arranged in the width direction also on the other main surface 10B of the sensor element 10, and two terminal fittings 220a and 220b are arranged to face the electrode pads 12a and 12b. And the protrusion part 220p provided in each of each terminal metal fitting 220a, 220b is each in point contact with electrode pad 12a, 12b.

特開２００７−７１５８２号公報JP 2007-71582 A 特開２００１−１８８０６０号公報（図４、図６）JP 2001-188060 A (FIGS. 4 and 6)

ところで、ガスセンサの小型化に相俟って、ガスセンサを構成するセンサ素子や各部品も狭小になり、ひいてはセンサ素子の板幅も狭小となるため、幅方向の電極パッドの寸法及び各電極パッドの間隔も狭くなる。又、端子金具の突起部を介して電極パッドとの電気的接続を行う方式を採用すると、接続部位が突起部の位置に制限されるという問題がある。
そのため、上記した図１０に示すガスセンサの場合、端子金具２１０ａ、２１０ｂ（２２０ａ、２２０ｂ）の突起部２１０ｐ（２２０ｐ）を端子金具の中心線Ｃｅから偏位させて配置し、かつセンサ素子１０の幅方向に見て、同じ面側の各端子金具２１０ａ、２１０ｂ（２２０ａ、２２０ｂ）の各突起部２１０ｐ（２２０ｐ）同士が近付くように配置している（つまり、中心線Ｃｅより内側に各突起部２１０ｐを配置する）。このようにすると、狭ピッチ化した各電極パッド１１ａ、１１ｂ（１２ａ、１２ｂ）の間隔に対応して各突起部２１０ｐ（２２０ｐ）の間隔を狭くすることができると共に、端子金具２１０ａ、２１０ｂ（２２０ａ、２２０ｂ）自身の幅を太くすることができ、これら端子金具の強度やバネ性を確保することができる。 By the way, along with the downsizing of the gas sensor, the sensor elements and parts constituting the gas sensor are also narrowed, and consequently the plate width of the sensor element is also narrowed. The interval is also narrowed. In addition, when a method of performing electrical connection with the electrode pad via the protruding portion of the terminal metal fitting is employed, there is a problem that the connection site is limited to the position of the protruding portion.
Therefore, in the case of the gas sensor shown in FIG. 10 described above, the protrusions 210p (220p) of the terminal fittings 210a, 210b (220a, 220b) are displaced from the center line Ce of the terminal fitting, and the width of the sensor element 10 When viewed in the direction, the protrusions 210p (220p) of the terminal fittings 210a, 210b (220a, 220b) on the same surface side are arranged so as to approach each other (that is, the protrusions 210p on the inner side of the center line Ce). Place). In this way, the interval between the protrusions 210p (220p) can be reduced corresponding to the interval between the electrode pads 11a, 11b (12a, 12b) having a reduced pitch, and the terminal fittings 210a, 210b (220a). 220b) The width of itself can be increased, and the strength and springiness of these terminal fittings can be ensured.

しかしながら、このように端子金具の中心線Ｃｅから突起部２１０ｐ（２２０ｐ）を偏位させた場合、同じ面側の各端子金具２１０ａ、２１０ｂ（２２０ａ、２２０ｂ）が左右反転した形状（鏡像）となるので、各端子金具が別部品となり、共通の端子金具とすることができずに部品点数の増大やコストアップに繋がるという問題がある。
一方、端子金具を左右対称の形状として共通化すべく、端子金具の中心線Ｃｅ上に突起部を設けようとすると、端子金具同士を接近させるために、セパレータの絶縁壁（図１０の１６６Ｐ）の厚みが小さくなってセパレータの絶縁壁が形成できない、もしくは絶縁壁を設けないと端子金具が緩衝して各電極パッドの間隔に対応できなくなる。又は、端子金具の緩衝を防止するために端子金具の幅を狭くすると強度やバネ性が低下する。
そこで、本発明は、端子金具自身の強度やバネ性を確保しつつ、センサ素子の狭小化に対応してセンサ素子の電極パッドと端子金具とを確実に電気的接続することができるガスセンサを提供することを目的とする。 However, when the protrusion 210p (220p) is displaced from the center line Ce of the terminal fitting in this way, the terminal fittings 210a, 210b (220a, 220b) on the same surface side are reversed left and right (mirror image). Therefore, there is a problem in that each terminal fitting becomes a separate part and cannot be made a common terminal fitting, resulting in an increase in the number of parts and an increase in cost.
On the other hand, if a projection is provided on the center line Ce of the terminal fitting in order to share the terminal fitting with a symmetrical shape, the insulating wall (166P in FIG. 10) of the separator is used to bring the terminal fitting closer together. As the thickness decreases, the insulating wall of the separator cannot be formed, or if the insulating wall is not provided, the terminal metal fittings are buffered and the distance between the electrode pads cannot be accommodated. Alternatively, if the width of the terminal fitting is reduced in order to prevent the terminal fitting from being buffered, the strength and springiness are reduced.
Therefore, the present invention provides a gas sensor that can reliably connect the electrode pad of the sensor element and the terminal fitting in response to the narrowing of the sensor element while ensuring the strength and springiness of the terminal fitting itself. The purpose is to do.

上記課題を解決するため、本発明のガスセンサは、軸線方向に延びると共に、対向する主面を有する板状をなし、少なくとも一方の主面の後端側に幅方向に並ぶ複数の電極パッドを有するセンサ素子と、前記電極パッドにそれぞれ接続される端子金具と、を備えるガスセンサであって、前記主面の幅方向において、複数の前記電極パッドのうち最も離れた２つの外縁間の最大間隔よりも、当該２つの電極パッドのそれぞれに接続する外側端子金具の幅方向の中心を通る中心線同士を結ぶ最小距離が広く、前記外側端子金具は、前記中心線を隔てるように頂点を有する、内側突起部及び外側突起部を有し、前記内側突起部の頂点が前記２つの電極パッドに接続している。
このガスセンサによれば、センサ素子の少なくとも一方の主面側にて、端子金具の中心線同士を結ぶ最小距離を、その端子金具が接続する２つの電極パッドの最大間隔より広くすることにより、ガスセンサの小型化（センサ素子の板幅の狭小化）に伴って板幅方向の電極パッドの寸法及び各電極パッドの間隔が狭くなっても、各電極パッドにそれぞれ接続される各端子金具の幅を太くすることができ、これら端子金具の強度やバネ性を確保することができる。
又、端子金具の中心線を隔てるように頂点を有する、内側突起部及び外側突起部を設けつつ、内側突起部の頂点を同じ主面側の電極パッドに接続させることにより、狭ピッチ化した各電極パッドの間隔に対応して、これに接する各頂点の間隔を狭くできると共に、各端子金具の形状が左右反転せず、同一形状（左右対称）となるので、各端子金具を共通として部品点数を低減することができる。 In order to solve the above problems, the gas sensor of the present invention has a plate shape extending in the axial direction and having opposing main surfaces, and has a plurality of electrode pads arranged in the width direction on the rear end side of at least one main surface. A gas sensor comprising a sensor element and a terminal fitting connected to each of the electrode pads, the width of the main surface being larger than the maximum distance between two outermost edges of the plurality of electrode pads in the width direction of the main surface. An inner protrusion having a wide minimum distance connecting the center lines passing through the center in the width direction of the outer terminal fitting connected to each of the two electrode pads, the outer terminal fitting having a vertex so as to separate the center line. And an outer protrusion, and the apex of the inner protrusion is connected to the two electrode pads.
According to this gas sensor, on at least one main surface side of the sensor element, the minimum distance connecting the center lines of the terminal fittings is made wider than the maximum distance between the two electrode pads to which the terminal fittings are connected. Even if the size of the electrode pads in the plate width direction and the interval between the electrode pads become narrower as the size of the sensor element becomes smaller (the width of the sensor element becomes narrower), the width of each terminal fitting connected to each electrode pad is reduced. The thickness can be increased, and the strength and springiness of these terminal fittings can be ensured.
Each of the pitches narrowed by connecting the apex of the inner protrusion to the electrode pad on the same main surface side while providing the inner protrusion and the outer protrusion having apexes so as to separate the center line of the terminal fitting. Corresponding to the electrode pad spacing, the distance between each apex in contact with it can be narrowed, and the shape of each terminal fitting is not reversed left and right, but is the same shape (symmetric). Can be reduced.

また、前記２つの電極パッド及び前記外側端子金具が、前記センサ素子を挟んで対向するように、前記センサ素子の他方の主面にもそれぞれ設けられており、前記センサ素子が前記端子金具の間に挿入されない状態で、対向した２つの前記外側端子金具のそれぞれについて、一方の外側端子金具に設けられた前記内側突起部及び前記外側突起部が、他方の前記端子金具に当接しているとよい。
このガスセンサによれば、センサ素子が端子金具の間に挿入される前において、端子金具は自身の幅方向の２箇所（各頂点）にて、対向する端子金具に当接するため、対向する端子金具同士がずれた方向に向くことが無く、略平行となる（片当たりが解消される）。その結果、センサ素子が端子金具間に挿入される際に、端子金具によって挿入困難となったり、軸ずれを生じて挿入されたりすることを抑制できる。 The two electrode pads and the outer terminal fitting are also provided on the other main surface of the sensor element so as to face each other with the sensor element interposed therebetween, and the sensor element is disposed between the terminal fittings. For each of the two outer terminal fittings facing each other without being inserted into the inner terminal fitting, the inner projection and the outer projection provided on one outer terminal fitting may be in contact with the other terminal fitting. .
According to this gas sensor, before the sensor element is inserted between the terminal fittings, the terminal fitting comes into contact with the opposing terminal fitting at two locations (each vertex) in its width direction. They are not parallel to each other and are substantially parallel (one-sided contact is eliminated). As a result, when the sensor element is inserted between the terminal fittings, it can be prevented that the insertion is difficult due to the terminal fittings, or the sensor element is inserted due to an axial deviation.

さらに、軸線方向に見て、前記内側突起部及び前記外側突起部の少なくとも一方は、先端縁から前記頂点までの距離が、前記頂点から後端縁までの距離よりも長いとよい。
このガスセンサによれば、突起部の傾斜は、頂点より先端側の方が、頂点より後端側よりもなだらかとなるため、センサ素子を端子金具に押し込んで挿入する際の抵抗力が軽減され、センサ素子の破損が防止される。 Furthermore, when viewed in the axial direction, at least one of the inner protrusion and the outer protrusion is preferably such that the distance from the leading edge to the vertex is longer than the distance from the vertex to the rear edge.
According to this gas sensor, since the inclination of the protrusion is gentler on the tip side than on the apex than on the rear end side from the apex, the resistance force when the sensor element is inserted into the terminal fitting is reduced, Damage to the sensor element is prevented.

この発明によれば、端子金具自身の強度やバネ性を確保しつつ、センサ素子の狭小化に対応してセンサ素子の電極パッドと端子金具とを確実に電気的接続することができるガスセンサを得ることができる。 According to the present invention, a gas sensor is obtained that can reliably connect the electrode pad of the sensor element and the terminal fitting in response to the narrowing of the sensor element while ensuring the strength and springiness of the terminal fitting itself. be able to.

本発明の実施形態に係るガスセンサの長手方向に沿う断面図である。It is sectional drawing which follows the longitudinal direction of the gas sensor which concerns on embodiment of this invention. センサ素子の斜視図である。It is a perspective view of a sensor element. 端子金具の斜視図である。It is a perspective view of a terminal metal fitting. 端子金具をセパレータに組み込んだ状態の断面斜視図である。It is a section perspective view in the state where a terminal metal fitting was built in a separator. 端子金具を保持すると共にセンサ素子が挿入されたセパレータの底面図である。It is a bottom view of the separator holding a terminal metal fitting and having a sensor element inserted. センサ素子が挿入されない状態で、端子金具を保持したセパレータの底面図である。It is a bottom view of the separator holding the terminal fitting in a state where the sensor element is not inserted. 端子金具の変形例を示す斜視図である。It is a perspective view which shows the modification of a terminal metal fitting. ５つの端子金具を保持すると共に、電極パッドが５つ形成されたセンサ素子が挿入されたセパレータの底面図である。It is a bottom view of the separator which inserted the sensor element in which five electrode pads were formed while holding five terminal metal fittings. 図８のセンサ素子が挿入される前において、対向する端子金具の重なり状態を示す側面図である。It is a side view which shows the overlapping state of the terminal metal fitting which opposes before the sensor element of FIG. 8 is inserted. 従来の端子金具を保持すると共にセンサ素子が挿入されたセパレータの底面図である。It is a bottom view of the separator which hold | maintained the conventional terminal metal fitting and in which the sensor element was inserted.

以下、本発明の実施形態について説明する。 Hereinafter, embodiments of the present invention will be described.

以下、本発明の実施形態について説明する。
図１は本発明の実施形態に係るガスセンサ（酸素センサ）２００の長手方向に沿う全体断面図、図２はセンサ素子１０の斜視図、図３は端子金具２１ａの斜視図、図４は端子金具をセパレータに組み込んだ状態の断面斜視図、図５は端子金具を保持すると共にセンサ素子１０が挿入されたセパレータ１６６の底面図、図６はセンサ素子１０が挿入されない状態で端子金具を保持したセパレータ１６６の底面図である。
このガスセンサ２００は、自動車や各種内燃機関の排気ガス中の酸素濃度を検出する酸素センサである。 Hereinafter, embodiments of the present invention will be described.
1 is an overall cross-sectional view of a gas sensor (oxygen sensor) 200 according to an embodiment of the present invention along the longitudinal direction, FIG. 2 is a perspective view of a sensor element 10, FIG. 3 is a perspective view of a terminal fitting 21a, and FIG. FIG. 5 is a bottom view of the separator 166 in which the sensor element 10 is inserted while holding the terminal fitting, and FIG. 6 is a separator holding the terminal fitting in a state in which the sensor element 10 is not inserted. 166 is a bottom view of FIG.
The gas sensor 200 is an oxygen sensor that detects the oxygen concentration in the exhaust gas of automobiles and various internal combustion engines.

図１において、ガスセンサ２００は、排気管に固定されるためのねじ部１３９が外表面に形成された筒状の主体金具１３８と、軸線Ｏ方向（ガスセンサ２００の長手方向：図中上下方向）に延びる板状形状をなすセンサ素子１０と、センサ素子１０の径方向周囲を取り囲むように配置される筒状のセラミックスリーブ１０６と、軸線方向に貫通する挿通孔１６８の先端側の内部に、センサ素子１０の後端部の周囲を取り囲む状態で配置されるセラミック製のセパレータ１６６と、センサ素子１０とセパレータ１６６との間に配置される４個の端子金具２１ａ、２１ｂ、２２ａ、２２ｂ（図１では、２個のみを図示）とを備えている。
又、センサ素子１０の先端のガス検出部１０ａは、アルミナ等の多孔質保護層２０で覆われている。 In FIG. 1, the gas sensor 200 includes a cylindrical metal shell 138 having a threaded portion 139 formed on the outer surface for fixing to an exhaust pipe, and an axis O direction (longitudinal direction of the gas sensor 200: up and down direction in the figure). The sensor element 10 having a plate-like shape that extends, a cylindrical ceramic sleeve 106 arranged so as to surround the periphery of the sensor element 10 in the radial direction, and the inside of the insertion hole 168 penetrating in the axial direction are provided inside the sensor element. 10, a ceramic separator 166 disposed so as to surround the periphery of the rear end portion, and four terminal fittings 21 a, 21 b, 22 a, 22 b disposed between the sensor element 10 and the separator 166 (in FIG. 1). Only two are shown).
Further, the gas detection portion 10a at the tip of the sensor element 10 is covered with a porous protective layer 20 such as alumina.

主体金具１３８は、ステンレスから構成され、軸線方向に貫通する貫通孔１５４を有し、貫通孔１５４の径方向内側に突出する棚部１５２を有する略筒状形状に構成されている。この貫通孔１５４には、センサ素子１０の先端部を自身の先端よりも突出させるように当該センサ素子１０が配置されている。さらに、棚部１５２は、軸線方向に垂直な平面に対して傾きを有する内向きのテーパ面として形成されている。 The metal shell 138 is made of stainless steel, has a through-hole 154 that penetrates in the axial direction, and has a substantially cylindrical shape that has a shelf 152 that protrudes radially inward of the through-hole 154. The sensor element 10 is disposed in the through hole 154 so that the tip of the sensor element 10 protrudes from the tip of the sensor element 10. Further, the shelf portion 152 is formed as an inwardly tapered surface having an inclination with respect to a plane perpendicular to the axial direction.

なお、主体金具１３８の貫通孔１５４の内部には、センサ素子１０の径方向周囲を取り囲む状態で環状形状のアルミナ製のセラミックホルダ１５１、粉末充填層１５３、１５６（以下、滑石リング１５３、１５６ともいう）、および上述のセラミックスリーブ１０６がこの順に先端側から後端側にかけて積層されている。
また、セラミックスリーブ１０６と主体金具１３８の後端部１４０との間には、加締めパッキン１５７が配置されており、セラミックホルダ１５１と主体金具１３８の棚部１５２との間には、滑石リング１５３やセラミックホルダ１５１を保持するための金属ホルダ１５８が配置されている。なお、主体金具１３８の後端部１４０は、加締めパッキン１５７を介してセラミックスリーブ１０６を先端側に押し付けるように、加締められている。 In addition, inside the through hole 154 of the metal shell 138, an annular ceramic holder 151 made of alumina and powder-filled layers 153 and 156 (hereinafter referred to as talc rings 153 and 156) surrounding the sensor element 10 in the radial direction. The ceramic sleeve 106 is laminated in this order from the front end side to the rear end side.
A caulking packing 157 is disposed between the ceramic sleeve 106 and the rear end portion 140 of the metal shell 138, and a talc ring 153 is disposed between the ceramic holder 151 and the shelf 152 of the metal shell 138. And a metal holder 158 for holding the ceramic holder 151 is disposed. Note that the rear end portion 140 of the metal shell 138 is crimped so as to press the ceramic sleeve 106 toward the distal end side via the crimping packing 157.

一方、図１に示すように、主体金具１３８の先端側（図１における下方）外周には、センサ素子１０の突出部分を覆うと共に、複数の孔部を有する金属製（例えば、ステンレスなど）二重のプロテクタである、外部プロテクタ１４２および内部プロテクタ１４３が溶接等によって取り付けられている。 On the other hand, as shown in FIG. 1, a metal (for example, stainless steel) 2 having a plurality of holes and covering the protruding portion of the sensor element 10 on the outer periphery of the front end side (lower side in FIG. 1) of the metal shell 138. An external protector 142 and an internal protector 143, which are heavy protectors, are attached by welding or the like.

そして、主体金具１３８の後端側外周には、外筒１４４が固定されている。また、外筒１４４の後端側（図１における上方）の開口部には、センサ素子１０の４個の端子金具２１ａ、２１ｂ、２２ａ、２２ｂ（図１では、２個のみを表示）とそれぞれ電気的に接続される４本のリード線１４６（図１では２本のみを表示）が挿通されるリード線挿通孔（図示せず）が形成された、ゴム製のグロメット１７０が配置されている。
さらに、グロメット１７０の軸線Ｏ方向中心には基準雰囲気となる大気を導入するための貫通孔１７０ｈが形成され、この貫通孔１７０ｈには円筒状のフィルタ金具１７２が嵌挿されている。そして、貫通孔１７０ｈとフィルタ金具１７２の間に、貫通穴１７０ｈを閉塞するようにして配置された、空気は通す（通気性を有す）が水を通さない撥水性フィルタ１７４が保持され、貫通孔１７０ｈを介してガスセンサ２００の内外に大気を導入可能になっている。 An outer cylinder 144 is fixed to the outer periphery of the rear end side of the metal shell 138. Further, the four terminal fittings 21a, 21b, 22a, and 22b (only two are shown in FIG. 1) of the sensor element 10 are respectively provided in the opening on the rear end side (upper side in FIG. 1) of the outer cylinder 144. A rubber grommet 170 in which lead wire insertion holes (not shown) through which four lead wires 146 (only two are shown in FIG. 1) to be electrically connected are formed is disposed. .
Further, a through-hole 170h for introducing air serving as a reference atmosphere is formed at the center of the grommet 170 in the axis O direction, and a cylindrical filter fitting 172 is fitted into the through-hole 170h. A water-repellent filter 174 that is disposed between the through hole 170h and the filter fitting 172 so as to close the through hole 170h and allows air to pass therethrough (air permeability) but does not allow water to pass therethrough is retained. The atmosphere can be introduced into and out of the gas sensor 200 through the hole 170h.

また、主体金具１３８の後端部１４０より突出されたセンサ素子１０の後端側（図１における上方）には、セパレータ１６６が配置される。なお、このセパレータ１６６は、センサ素子１０の後端側の主面に形成される合計４個の電極パッド（図１では２個の電極パッド１１ａ、１２ａのみを表示）の周囲に配置される。このセパレータ１６６は、軸線方向に貫通する挿通孔１６８を有する筒状形状に形成されると共に、外表面から径方向外側に突出する鍔部１６７が備えられている。セパレータ１６６は、鍔部１６７が保持部材１６９を介して外筒１４４に当接することで、外筒１４４の内部に保持される。 A separator 166 is disposed on the rear end side (upper side in FIG. 1) of the sensor element 10 protruding from the rear end portion 140 of the metal shell 138. The separator 166 is arranged around a total of four electrode pads (only two electrode pads 11a and 12a are shown in FIG. 1) formed on the main surface on the rear end side of the sensor element 10. The separator 166 is formed in a cylindrical shape having an insertion hole 168 penetrating in the axial direction, and is provided with a flange portion 167 protruding outward in the radial direction from the outer surface. The separator 166 is held inside the outer cylinder 144 by the flange portion 167 coming into contact with the outer cylinder 144 via the holding member 169.

図２に示すようにセンサ素子１０は、軸線Ｏ方向に延びる板状をなし、先端部１０ｓが酸素濃度を検出するガス検出部１０ａとなっていて、ガス検出部１０ａは多孔質保護層２０で覆われている。なお、センサ素子１０自身は公知の構成であり、図示はしないが酸素イオン透過性の固体電解質体と１対の電極とを有するガス検出部と、ガス検出部を加熱して一定温度に保持するヒータ部とを備えている。
そして、センサ素子１０の一方の主面１０Ａの後端側には、幅Ｗ方向に２つの電極パッド１１ａ、１１ｂが並び、ガス検出部からのセンサ出力信号がリード部（図示せず）を介してこれら電極パッド１１ａ、１１ｂから出力される。又、主面１０Ａに対向するように設けられた他方の主面１０Ｂの後端側には、幅方向に２つの電極パッド１２ａ、１２ｂが並び、リード部（図示せず）を介してヒータ部に電力を供給するようになっている。
各電極パッド１１ａ、１１ｂ、１２ａ、１２ｂは、軸線Ｏ方向に長い矩形状になっていて、例えばＰｔを主体とする焼結体として形成することができる。なお、本実施形態では、センサ素子１０の各面に配置された電極パッド１１ａ、１１ｂと、電極パッド１２ａ、１２ｂとは互いに対向し、具体的には、電極パッド１１ａと電極パッド１２ａが対向し、電極パッド１１ｂと電極パッド１２ｂが対向している。 As shown in FIG. 2, the sensor element 10 has a plate shape extending in the direction of the axis O, the tip portion 10 s is a gas detection portion 10 a that detects the oxygen concentration, and the gas detection portion 10 a is a porous protective layer 20. Covered. The sensor element 10 itself has a known configuration, and although not shown, the gas detector having an oxygen ion permeable solid electrolyte body and a pair of electrodes, and the gas detector are heated and maintained at a constant temperature. And a heater unit.
Two electrode pads 11a and 11b are arranged in the width W direction on the rear end side of one main surface 10A of the sensor element 10, and a sensor output signal from the gas detection unit is passed through a lead unit (not shown). Output from these electrode pads 11a and 11b. In addition, two electrode pads 12a and 12b are arranged in the width direction on the rear end side of the other main surface 10B provided to face the main surface 10A, and the heater portion is interposed via a lead portion (not shown). It is designed to supply power.
Each electrode pad 11a, 11b, 12a, 12b has a rectangular shape that is long in the direction of the axis O, and can be formed as a sintered body mainly composed of Pt, for example. In the present embodiment, the electrode pads 11a and 11b and the electrode pads 12a and 12b arranged on each surface of the sensor element 10 face each other. Specifically, the electrode pad 11a and the electrode pad 12a face each other. The electrode pad 11b and the electrode pad 12b are opposed to each other.

図３は端子金具２１ａの斜視図を示す。なお、本実施形態では、後述するようにガスセンサ２００は４本の端子金具２１ａ、２１ｂ、２２ａ、２２ｂを有するが、これら４本の端子金具はいずれも同一形状であるので端子金具２１ａについてのみ説明するが、他の端子金具２１ｂ、２２ａ、２２ｂの構成も同様である。
図３に示すように、端子金具２１ａは、略板状をなして軸線Ｏ方向に延びる板状の本体部２１１ａと、本体部２１１ａの先端から後端に向かって折り返された先端部２１１ｂと、本体部２１１ａの後端に接続する圧着端子部２１１ｃと、本体部２１１ａの軸線Ｏ方向ほぼ中央の両端から先端部２１１ｂの折り返し方向（後述するセンサ素子１０側）に向かって延び、本体部２１１ａの両端からそれぞれＬ字状に折曲する１対の抜け止め部２１１ｄとを一体に備えている。なお、本体部２１１ａと抜け止め部２１１ｄとの折り返し線は軸線Ｏ方向に平行であり、軸線Ｏ方向から見て、１対の抜け止め部２１１ｄは本体部２１１ａを挟んで平行に延びている。又、１対の抜け止め部２１１ｄの後端向き面２１１ｔが面一になっている。
圧着端子部２１１ｃは公知の筒状をなし、この筒内に被覆を向いて導線を露出させたリード線１４６を挿入して圧着することで、リード線１４６（図１参照）が電気的に接続される。
端子金具２１ａは、例えば１枚の金属板（インコネル（登録商標）等）を打ち抜いた後、先端部２１１ｂ及び抜け止め部２１１ｄを折り曲げて製造することができるが、これに限定されない。 FIG. 3 shows a perspective view of the terminal fitting 21a. In this embodiment, as will be described later, the gas sensor 200 has four terminal fittings 21a, 21b, 22a, and 22b. Since these four terminal fittings have the same shape, only the terminal fitting 21a will be described. However, the configurations of the other terminal fittings 21b, 22a, and 22b are the same.
As shown in FIG. 3, the terminal fitting 21a includes a plate-shaped main body portion 211a that is substantially plate-shaped and extends in the direction of the axis O, a front-end portion 211b that is folded back from the front end of the main body portion 211a toward the rear end, A crimp terminal portion 211c connected to the rear end of the main body portion 211a, and extends from both ends of the center portion 211a in the direction of the axis O toward the folding direction of the front end portion 211b (sensor element 10 side described later), A pair of retaining portions 211d that are bent in an L shape from both ends are integrally provided. The folding line between the main body portion 211a and the retaining portion 211d is parallel to the axis O direction, and when viewed from the axis O direction, the pair of retaining portions 211d extend in parallel across the main body portion 211a. Further, the rear end facing surface 211t of the pair of retaining portions 211d is flush.
The crimp terminal portion 211c has a known cylindrical shape, and the lead wire 146 (see FIG. 1) is electrically connected by inserting and crimping the lead wire 146 with the conductive wire exposed in the cylinder. Is done.
The terminal fitting 21a can be manufactured, for example, by punching a single metal plate (Inconel (registered trademark) or the like) and then bending the tip end portion 211b and the retaining portion 211d, but is not limited thereto.

先端部２１１ｂの先端縁は後端に向かって折り返されている。そして、先端部２１１ｂの表面（本体部２１１ａに対向する面の反対面）には、端子金具２１ａ（及び先端部２１１ｂ）の幅方向中心線Ｃｅを隔てて、それぞれ突起部２１ｐが１個形成され、さらに突起部２１ｐには頂点２１ｈが形成されている。なお、各突起部２１ｐは同一形状であって、それぞれ軸線Ｏ方向の同じ位置に並んでいる。
又、図３の例では、軸線Ｏ方向に見て、突起部２１ｐの先端縁から頂点２１ｈまでの距離ｄ１は、頂点２１ｈから突起部２１ｐの後端縁までの距離ｄ２よりも長い。このようにすると、先端部２１１ｂの表面を基準とする突起部２１ｐの傾斜は、頂点２１ｈより先端側の方が、頂点２１ｈより後端側よりもなだらかとなる。このため、センサ素子１０を端子金具２１ａ（及び端子金具２１ｂ、２２ａ、２２ｂ）に押し込んで挿入する際の抵抗力が軽減され、センサ素子１０の破損が防止されるので好ましい。
なお、突起部２１ｐ（頂点２１ｈ）を含む先端部２１１ｂは、端子金具２１ａ自身のバネ性（弾性）によって電極パッド１１ａ側に押圧されることにより、確実な電気的接続が得られるようになっている。 The front end edge of the front end portion 211b is folded back toward the rear end. Then, one protrusion 21p is formed on the surface of the tip portion 211b (the surface opposite to the surface facing the main body portion 211a) with the width direction center line Ce of the terminal fitting 21a (and the tip portion 211b) separated. Furthermore, a vertex 21h is formed on the protrusion 21p. The protrusions 21p have the same shape and are arranged at the same position in the axis O direction.
In the example of FIG. 3, the distance d1 from the tip edge of the protrusion 21p to the vertex 21h is longer than the distance d2 from the vertex 21h to the rear edge of the protrusion 21p when viewed in the axis O direction. In this way, the inclination of the protrusion 21p with respect to the surface of the tip end portion 211b is gentler at the tip end side than the apex 21h than at the rear end side from the apex 21h. For this reason, since the resistance force at the time of pushing and inserting the sensor element 10 in the terminal metal fitting 21a (and the terminal metal fittings 21b, 22a, and 22b) is reduced and damage to the sensor element 10 is prevented, it is preferable.
The tip 211b including the protrusion 21p (vertex 21h) is pressed toward the electrode pad 11a by the spring property (elasticity) of the terminal fitting 21a itself, so that a reliable electrical connection can be obtained. Yes.

又、図４に示すように、端子金具２１ａ、２１ｂ、２２ａ、２２ｂは、互いに接触しないよう隔離された状態でセパレータ１６６内に保持されると共に、挿通孔１６８に臨んでいる。具体的には、セパレータ１６６内の軸線Ｏ方向に４つの端子収納穴（図示せず）が貫通しており、これら各端子収納穴にそれぞれ端子金具２１ａ、２１ｂ、２２ａ、２２ｂが互いに隔離して保持されるようになっている。
ここで、セパレータ１６６内の端子収納穴に先端側から端子金具２１ａ（端子金具２１ｂ、２２ａ、２２ｂも同様）を挿入すると、１対の抜け止め部２１１ｄの後端向き面２１１ｔが、セパレータ１６６の先端向き面１６６ｓに当接する。これにより、端子金具２１ａが先端向き面１６６ｓより後端側に抜けるのを防止し、軸線Ｏ方向に端子金具２１ａの位置を規制する。
さらに図３に示すように、本実施形態では、各抜け止め部２１１ｄの板面のうち、先端縁から後端に向かって切れ目が入れられ、切れ目部分が抜け止め部２１１ｄの板面から外側に、かつ先端側に向かって拡がって片状の係止部２１１ｗを形成する。この１対の係止部２１１ｗは軸線Ｏ方向に垂直な方向から見てハの字状になっている。そして、１対の羽根部２１１ｗは端子収納穴内で拡開して端子収納穴の壁面に当接する。これにより、端子収納穴と端子金具２１ａとの隙間を羽根部２１１ｗが埋め、軸線Ｏ周りの端子金具２１ａの回転を防止すると共に、軸線Ｏ方向に垂直な方向にて端子金具２１ａを位置決めして保持する。なお、本実施形態では、羽根部２１１ｗを本体部２１１ａの両辺に１対設けているので、本体部２１１ａの両辺側にて端子収納穴と端子金具２１ａとの間の隙間を均等に（図３の左右の両方向から）埋め、端子収納穴の中央に端子金具２１ａを位置決めし易くなる。
又、係止部２１１ｗが外側、かつ先端側に向かって拡がることで、端子金具２１ａを先端側へ引き抜こうとしても係止部２１１ｗがさらに拡がって引き抜き力に対抗するので、端子金具２１ａの先端側への抜けを有効に防止することができる。 As shown in FIG. 4, the terminal fittings 21a, 21b, 22a, 22b are held in the separator 166 in a state of being isolated so as not to contact each other, and face the insertion hole 168. Specifically, four terminal receiving holes (not shown) penetrate in the direction of the axis O in the separator 166, and the terminal fittings 21a, 21b, 22a, 22b are isolated from each other in the terminal receiving holes, respectively. It is supposed to be retained.
Here, when the terminal fitting 21a (the same applies to the terminal fittings 21b, 22a, and 22b) is inserted into the terminal receiving hole in the separator 166 from the front end side, the rear end facing surface 211t of the pair of retaining portions 211d is formed on the separator 166. It abuts on the tip-facing surface 166s. Thus, the terminal fitting 21a is prevented from coming out to the rear end side from the front end facing surface 166s, and the position of the terminal fitting 21a is regulated in the axis O direction.
Further, as shown in FIG. 3, in the present embodiment, among the plate surfaces of each retaining portion 211d, a break is made from the leading edge toward the rear end, and the break portion is outward from the plate surface of the retaining portion 211d. And it expands toward the front end side to form a piece-like locking portion 211w. The pair of locking portions 211w has a square shape when viewed from a direction perpendicular to the direction of the axis O. And a pair of blade | wing part 211w expands in a terminal storage hole, and contact | abuts to the wall surface of a terminal storage hole. As a result, the blade portion 211w fills the gap between the terminal housing hole and the terminal fitting 21a, preventing the rotation of the terminal fitting 21a around the axis O, and positioning the terminal fitting 21a in a direction perpendicular to the direction of the axis O. Hold. In the present embodiment, since a pair of blade portions 211w are provided on both sides of the main body portion 211a, the gaps between the terminal housing holes and the terminal fittings 21a are evenly distributed on both sides of the main body portion 211a (FIG. 3). It is easy to position the terminal fitting 21a in the center of the terminal receiving hole.
Further, since the locking portion 211w expands outward and toward the distal end side, the locking portion 211w further expands and resists the pulling force even if the terminal fitting 21a is pulled out toward the distal end side. It is possible to effectively prevent the slipping out to the side.

図５は、端子金具２１ａ、２１ｂ、２２ａ、２２ｂを保持すると共にセンサ素子１０が挿入されたセパレータ１６６の底面図である。但し、図５において、センサ素子１０先端の多孔質保護層２０を省略している。
図５において、センサ素子１０の一方の主面１０Ａ側にて、電極パッド１１ａ、１１ｂに２つの端子金具２１ａ、２１ｂがそれぞれ対向している。そして、センサ素子１０の幅Ｗ方向における（最も離れた）２つの電極パッド１１ａ、１１ｂの外縁間の最大間隔Ｇ２より、端子金具２１ａ、２１ｂの中心線Ｃｅ同士を結ぶ最小距離Ｇ１の方が広くなっている。さらに、各端子金具２１ａ、２１ｂのそれぞれに２個ずつ設けられた突起部２１ｐの頂点２１ｈのうち、中心線Ｃｅより内側の内側突起部２１ｐ１の頂点２１ｈ１が、電極パッド１１ａ、１１ｂにそれぞれ接続している。
同様に、センサ素子１０の他方の主面１０Ｂにおいても、電極パッド１２ａ、１２ｂに２つの端子金具２２ａ、２２ｂがそれぞれ対向している。そして、センサ素子１０の幅Ｗ方向における２つの電極パッド１２ａ、１２ｂの外縁間の最大間隔Ｇ４（＝Ｇ２）より、端子金具２２ａ、２２ｂの中心線Ｃｅ同士を結ぶ最小距離Ｇ３（＝Ｇ１）の方が広くなっている。さらに、各端子金具２２ａ、２２ｂのそれぞれに２個ずつ設けられた突起部２２ｐの頂点２２ｈのうち、中心線Ｃｅより内側に位置する内側突起部２２ｐ１の頂点２２ｈ１が、電極パッド１２ａ、１２ｂにそれぞれ接続している。
なお、図５の例では、Ｇ４＝Ｇ２、かつＧ３＝Ｇ１とし、Ｇ３及びＧ４を省略したが、Ｇ４とＧ２が異なってもよく、及び／又はＧ３とＧ１が異なっていてもよい（後述の図８参照）。又、センサ素子１０の少なくとも一方の面にてＧ２＜Ｇ１又はＧ４＜Ｇ３を満たせばよい。 FIG. 5 is a bottom view of the separator 166 that holds the terminal fittings 21a, 21b, 22a, and 22b and that has the sensor element 10 inserted therein. However, in FIG. 5, the porous protective layer 20 at the tip of the sensor element 10 is omitted.
In FIG. 5, two terminal fittings 21a and 21b are opposed to the electrode pads 11a and 11b on the one main surface 10A side of the sensor element 10, respectively. The minimum distance G1 connecting the center lines Ce of the terminal fittings 21a and 21b is wider than the maximum gap G2 between the outer edges of the two electrode pads 11a and 11b in the width W direction of the sensor element 10 (the furthest away). It has become. Furthermore, out of the vertices 21h of the two protrusions 21p provided on each of the terminal fittings 21a and 21b, the vertices 21h1 of the inner protrusions 21p1 inside the center line Ce are connected to the electrode pads 11a and 11b, respectively. ing.
Similarly, also on the other main surface 10B of the sensor element 10, the two terminal fittings 22a and 22b face the electrode pads 12a and 12b, respectively. The minimum distance G3 (= G1) connecting the center lines Ce of the terminal fittings 22a and 22b is determined from the maximum gap G4 (= G2) between the outer edges of the two electrode pads 12a and 12b in the width W direction of the sensor element 10. Is wider. Further, out of the vertices 22h of the two protrusions 22p provided on each of the terminal fittings 22a and 22b, the vertices 22h1 of the inner protrusions 22p1 located inside the center line Ce are respectively provided on the electrode pads 12a and 12b. Connected.
In the example of FIG. 5, G4 = G2 and G3 = G1, and G3 and G4 are omitted. However, G4 and G2 may be different and / or G3 and G1 may be different (described later). (See FIG. 8). Further, at least one surface of the sensor element 10 may satisfy G2 <G1 or G4 <G3.

以上のように、センサ素子１０の同じ主面１０Ａ（又は１０Ｂ）側にてＧ２＜Ｇ１（又はＧ４＜Ｇ３）とすることにより、ガスセンサ２００の小型化（センサ素子１０の板幅の狭小化）に伴って板幅方向の電極パッド１１ａ、１１ｂ（又は１２ａ、１２ｂ）の寸法及び各電極パッドの間隔が狭くなっても、各電極パッドにそれぞれ接続される各端子金具２１ａ、２１ｂ（又は２２ａ、２２ｂ）の幅を太くすることができ、これら端子金具の強度やバネ性を確保することができる。
又、本発明では、端子金具２１ａ、２１ｂ（又は２２ａ、２２ｂ）の中心線Ｃｅを隔てるように、それぞれ頂点２１ｈ１、頂点２１ｈ２（又は２２ｈ１、２２ｈ２）が形成された内側突起部２１ｐ１（又は２２ｐ１）及び外側突起部２１ｐ２（又は２２ｐ２）を設けつつ、内側突起部２１ｐ１（又は２２ｐ１）の頂点２１ｈ１（又は２２ｈ１）を同じ主面側の２つの電極パッド１１ａ、１１ｂ（又は１２ａ、１３ｂ）に接続させている。これにより、狭ピッチ化した各電極パッドの間隔に対応して、これに接する各頂点の間隔を狭くできると共に、各端子金具２１ａ、２１ｂ（又は２２ａ、２２ｂ）の形状が左右反転せず、同一形状（左右対称）となるので、各端子金具を共通として部品点数を低減することができる。
つまり、本発明によれば、端子金具自身の強度やバネ性を確保しつつ、センサ素子の狭小化に対応してセンサ素子の電極パッドと端子金具とを確実に電気的接続することができる。 As described above, by making G2 <G1 (or G4 <G3) on the same main surface 10A (or 10B) side of the sensor element 10, the gas sensor 200 is reduced in size (the plate width of the sensor element 10 is reduced). Accordingly, even if the dimensions of the electrode pads 11a, 11b (or 12a, 12b) in the plate width direction and the intervals between the electrode pads become narrower, the terminal fittings 21a, 21b (or 22a, The width of 22b) can be increased, and the strength and springiness of these terminal fittings can be ensured.
In the present invention, the inner protrusion 21p1 (or 22p1) is formed with the apex 21h1 and the apex 21h2 (or 22h1, 22h2), respectively, so as to separate the center line Ce of the terminal fittings 21a, 21b (or 22a, 22b). And the outer protrusion 21p2 (or 22p2), the vertex 21h1 (or 22h1) of the inner protrusion 21p1 (or 22p1) is connected to the two electrode pads 11a, 11b (or 12a, 13b) on the same main surface side. ing. Accordingly, the distance between the apexes in contact with each electrode pad with a narrow pitch can be reduced, and the shape of each terminal fitting 21a, 21b (or 22a, 22b) is not reversed left and right, and is the same. Since it has a shape (symmetric), the number of parts can be reduced by using each terminal fitting in common.
In other words, according to the present invention, the electrode pad of the sensor element and the terminal fitting can be reliably electrically connected in response to the narrowing of the sensor element while ensuring the strength and springiness of the terminal fitting itself.

図６はセンサ素子１０が挿入されない状態で、端子金具２１ａ、２１ｂ、２２ａ、２２ｂを保持したセパレータ１６６の底面図である。なお、図６において、センサ素子１０先端の多孔質保護層２０を省略している。
図６において、各端子金具２１ａ、２１ｂ、２２ａ、２２ｂが同一形状であり、かつＧ１＝Ｇ３である。そのため、センサ素子１０の各主面１０Ａ、１０Ｂに配置された端子金具同士（具体的には端子金具２１ａ、２２ａ同士、及び、端子金具２１ｂ、２２ｂ同士）が対向すると、一方の端子金具２１ａ、２１ｂの内側突起部２１ｐ１及び外側突起部２１ｐ２の頂点２１ｈ１、２１ｈ２が、対向する端子金具２２ａ、２２ｂの内側突起部２２ｐ１及び外側突起部２２ｐ２の頂点２２ｈ１、２２ｈ２に当接する。
このようにすると、端子金具２１ａは自身の幅方向の２箇所（各頂点２１ｈ１、２１ｈ２）にて、対向する端子金具２２ａの各頂点（２２ｈ１、２２ｈ２）に当接する。このため、対向する端子金具２１ａ、２２ａ同士がずれた方向（例えば、ハの字方向）に向くことが無く、略平行となる（つまり、片当たりが解消される）という利点がある。その結果、センサ素子１０が端子金具２１ａ、２２ａ間に挿入される際に、端子金具２１ａ、２２ａによって挿入困難となったり、軸ずれを生じて挿入されたりすることを抑制できる。
なお、互いに対向する他の端子金具２１ｂ、２２ｂについても同様である。
又、図６の例では、対向した端子金具２１ａ、２２ａの頂点２１ｈ、２２ｈ同士が当接しているが、要は端子金具が相手となる端子金具と幅方向の２箇所で接していればよく、後述する図９に示すように、相手となる端子金具の頂点以外の部分に当接してもよい。
本実施形例では、端子金具２１ａ、２１ｂ、２２ａ、２２ｂが特許請求の範囲の「外側端子金具」に相当する。 FIG. 6 is a bottom view of the separator 166 holding the terminal fittings 21a, 21b, 22a, 22b in a state where the sensor element 10 is not inserted. In FIG. 6, the porous protective layer 20 at the tip of the sensor element 10 is omitted.
In FIG. 6, the terminal fittings 21a, 21b, 22a, 22b have the same shape, and G1 = G3. Therefore, when the terminal fittings (specifically, the terminal fittings 21a and 22a and the terminal fittings 21b and 22b) arranged on the main surfaces 10A and 10B of the sensor element 10 face each other, one terminal fitting 21a, The vertices 21h1, 21h2 of the inner projection 21p1 and the outer projection 21p2 of 21b abut against the vertices 22h1, 22h2 of the inner projection 22p1 and the outer projection 22p2 of the opposing terminal fittings 22a, 22b.
If it does in this way, the terminal metal fitting 21a will contact | abut each vertex (22h1, 22h2) of the terminal metal fitting 22a which opposes in two places (each vertex 21h1, 21h2) of own width direction. For this reason, there is an advantage that the terminal fittings 21a and 22a facing each other are not parallel to each other (for example, the C-shaped direction) and are substantially parallel (that is, the one-sided contact is eliminated). As a result, when the sensor element 10 is inserted between the terminal fittings 21a and 22a, it is possible to prevent the insertion of the sensor fitting 10 from being difficult due to the terminal fittings 21a and 22a or being inserted due to an axial deviation.
The same applies to the other terminal fittings 21b and 22b facing each other.
Further, in the example of FIG. 6, the apexes 21h and 22h of the terminal fittings 21a and 22a facing each other are in contact with each other. In short, it is sufficient that the terminal fitting is in contact with the terminal fitting with which it is mated at two places in the width direction. As shown in FIG. 9, which will be described later, it may be in contact with a portion other than the apex of the terminal fitting as a counterpart.
In this embodiment, the terminal fittings 21a, 21b, 22a, 22b correspond to “outer terminal fittings” in the claims.

図７は端子金具２１ａの変形例を示す斜視図である。なお、ガスセンサが有する４本の端子金具はいずれも同一形状であり、他の端子金具の構造も端子金具２３ａと同様である。又、端子金具２３ａは、突起部２３ｐの構成が異なること以外は、図３の端子金具２１ａと同一であるので、同一構成部分の説明を省略する。但し、端子金具２１ａと同一部分の符号は、例えば符号２１１ｃを２３１ｃに読み替えるものとする。
図７において、先端部２３１ｂの表面（本体部２３１ａに対向する面の反対面）には、中心線Ｃｅを隔てるように、突起部２３ｐがそれぞれ１個形成され、さらに突起部２３ｐには頂点２３ｈが形成されている。ここで、各突起部２３ｐは同一形状であるが、それぞれ軸線Ｏ方向の異なる位置にずれて並んでいる。
又、突起部２３ｐはほぼ半球状であって、突起部２３ｐの先端縁からから頂点２３ｈまでの距離と、頂点２３ｈから突起部２３ｐの後端縁までの距離は同一である。さらに、各突起部２３ｐ自身は中心線Ｃｅを超えて反対側まで形成されているが、突起部２３ｐの頂点２３ｈ自身は中心線Ｃｅを隔てた位置にそれぞれ配置されている。このように、少なくとも頂点２３ｈが中心線Ｃｅを隔てた位置にあればよい。 FIG. 7 is a perspective view showing a modification of the terminal fitting 21a. The four terminal fittings included in the gas sensor have the same shape, and the structure of the other terminal fittings is the same as that of the terminal fitting 23a. Further, since the terminal fitting 23a is the same as the terminal fitting 21a of FIG. 3 except that the configuration of the protruding portion 23p is different, the description of the same components will be omitted. However, the reference numerals of the same parts as the terminal fittings 21a are read as, for example, reference numerals 211c to 231c.
In FIG. 7, one protrusion 23p is formed on the surface of the tip 231b (opposite the surface facing the main body 231a) so as to separate the center line Ce, and the protrusion 23p has a vertex 23h. Is formed. Here, although each projection part 23p is the same shape, it has shifted and arranged in the position where the axis line O direction differs, respectively.
The protrusion 23p is substantially hemispherical, and the distance from the leading edge of the protrusion 23p to the vertex 23h is the same as the distance from the vertex 23h to the rear edge of the protrusion 23p. Furthermore, each protrusion 23p itself is formed to the opposite side beyond the center line Ce, but the vertex 23h itself of the protrusion 23p is disposed at a position separated from the center line Ce. Thus, it is sufficient that at least the vertex 23h is located at a position separating the center line Ce.

次に、図８、図９を参照し、センサ素子１０ｘが５つの電極パッドを備え、Ｇ４とＧ２が同一でない場合について説明する。５つの電極パッドを備えたセンサ素子１０ｘを有するガスセンサとしては、全領域空燃比センサが該当する。なお、図８、図９においては、図７に示す端子金具２３ａを用いるものとし、端子金具２３ａと同一形状の４本の端子金具を符号２３ａ、２３ｂ、２４ａ、２４ｂで表すと共に、端子金具２４ａ、２４ｂに形成された突起部及び頂点を、それぞれ符号２４ｐ、２４ｈで表す。
図８において、このセンサ素子１０ｘは、センサ素子１０の各電極パッド１１ａ、１１ｂ、１２ａ、１２ｂにそれぞれ対応する電極パッド１１ｄ、１１ｅ、１２ｄ、１２ｅの他に、幅方向に沿って電極パッド１２ｄ、１２ｅの間に５つ目の電極パッド１２ｆを備えている。
センサ素子１０ｘの場合、一方の主面（図８の下面）側の幅Ｗ方向には３つの電極パッド１２ｄ〜１２ｆが並ぶため、これら電極パッドの間隔を広げるべく、幅Ｗ方向に最も離れた２つの電極パッド１２ｄ、１２ｅの外縁間の間隔Ｇ４を、センサ素子１０ｘの他方の主面（図８の上面）側の２つの電極パッド１１ｄ、１１ｅの外縁間の間隔Ｇ２より若干広くしている。
一方、電極パッド１２ｄ、１２ｅにそれぞれ接続される端子金具２４ａ、２４ｂの中心線Ｃｅ同士を結ぶ距離Ｇ３は、電極パッド１１ｄ、１１ｅにそれぞれ接続される端子金具２３ａ、２３ｂの中心線Ｃｅ同士を結ぶ距離Ｇ１と同一とし（Ｇ３＝Ｇ１）、さらにＧ４＜Ｇ３としている。なお、幅Ｗ方向に沿って端子金具２４ａ、２４ｂの間には、電極パッド１２ｆに接続される端子金具２５が配置され、端子金具２５には突起部２５ｐが形成されている。このように、２つの電極パッドの外縁間の間隔については、本発明において、最大間隙にて考えることとする。一方、端子金具の中心線同士を結ぶ距離については、最小距離にて考えることとする。
図８の実施形態においても、Ｇ２＜Ｇ１（又はＧ４＜Ｇ３）とすることにより、電極パッドの寸法及び各電極パッドの間隔が狭くなっても、各電極パッド１１ａ、１１ｂ、１２ａ、１２ｂにそれぞれ接続される各端子金具２３ａ、２３ｂ、２４ａ、２４ｂの幅を太くすることができ、これら端子金具の強度やバネ性を確保することができる。
又、端子金具の中心線Ｃｅを隔てるように、それぞれ頂点２３ｈ１、頂点２３ｈ２（又は２４ｈ１、２４ｈ２）が形成された内側突起部２３ｐ１（又は２４ｐ１）及び外側突起部２３ｐ２（又は２４ｐ２）を設けつつ、内側突起部２３ｐ２（又は２４ｐ２）の頂点２３ｈ１（又は２４ｈ１）を同じ主面側の２つの電極パッドに接続させるので、狭ピッチ化した各電極パッドの間隔に対応して、これに接する各頂点の間隔を狭くできると共に、各端子金具２３ａ、２３ｂ（又は２４ａ、２４ｂ）の形状が左右反転せず、同一形状（左右対称）となるので、各端子金具を共通として部品点数を低減することができる。
なお、本変形例では、端子金具２３ａ、２３ｂ、２４ａ、２４ｂが特許請求の範囲の「外側端子金具」に相当する。 Next, a case where the sensor element 10x includes five electrode pads and G4 and G2 are not the same will be described with reference to FIGS. As a gas sensor having the sensor element 10x having five electrode pads, an all-range air-fuel ratio sensor is applicable. 8 and 9, the terminal fitting 23a shown in FIG. 7 is used, and four terminal fittings having the same shape as the terminal fitting 23a are denoted by reference numerals 23a, 23b, 24a, 24b, and the terminal fitting 24a. , 24b, and the protrusions and vertices formed by 24b and 24h, respectively.
In FIG. 8, the sensor element 10x includes electrode pads 12d, 11d, 11d, 12d, and 12e corresponding to the electrode pads 11a, 11b, 12a, and 12b of the sensor element 10 along the width direction. A fifth electrode pad 12f is provided between 12e.
In the case of the sensor element 10x, since the three electrode pads 12d to 12f are arranged in the width W direction on one main surface (the lower surface in FIG. 8), they are farthest from each other in the width W direction so as to widen the distance between these electrode pads. The gap G4 between the outer edges of the two electrode pads 12d and 12e is slightly wider than the gap G2 between the outer edges of the two electrode pads 11d and 11e on the other main surface (upper surface in FIG. 8) side of the sensor element 10x. .
On the other hand, the distance G3 connecting the center lines Ce of the terminal fittings 24a and 24b connected to the electrode pads 12d and 12e, respectively, connects the center lines Ce of the terminal fittings 23a and 23b connected to the electrode pads 11d and 11e, respectively. It is the same as the distance G1 (G3 = G1), and G4 <G3. A terminal fitting 25 connected to the electrode pad 12f is disposed between the terminal fittings 24a and 24b along the width W direction, and a protrusion 25p is formed on the terminal fitting 25. As described above, the distance between the outer edges of the two electrode pads is considered as the maximum gap in the present invention. On the other hand, the distance connecting the center lines of the terminal fittings is considered as the minimum distance.
Also in the embodiment of FIG. 8, by setting G2 <G1 (or G4 <G3), the electrode pads 11a, 11b, 12a, and 12b are respectively provided even when the electrode pad dimensions and the distance between the electrode pads are reduced. The width of each terminal fitting 23a, 23b, 24a, 24b to be connected can be increased, and the strength and springiness of these terminal fittings can be ensured.
Moreover, while providing the inner protrusion 23p1 (or 24p1) and the outer protrusion 23p2 (or 24p2) formed with the vertex 23h1, vertex 23h2 (or 24h1, 24h2), respectively, so as to separate the center line Ce of the terminal fitting, Since the apex 23h1 (or 24h1) of the inner protrusion 23p2 (or 24p2) is connected to the two electrode pads on the same main surface side, the apex of each apex in contact with the electrode pad corresponding to the interval between the electrode pads with a narrow pitch is established. The interval can be narrowed, and the shapes of the terminal fittings 23a, 23b (or 24a, 24b) are not reversed left and right but are the same shape (symmetric), so that the number of parts can be reduced by sharing the terminal fittings. .
In this modification, the terminal fittings 23a, 23b, 24a, and 24b correspond to the “outer terminal fitting” in the claims.

図９は、センサ素子１０ｘが挿入されない状態で、対向する端子金具２３ａ、２４ａの重なり状態を示す側面図（軸線Ｏ方向に直交する方向から見た図）である。
図９において、端子金具２３ａ、２４ａは重なっている。一方、端子金具２３ａの１対の突起部２３ｐ（頂点２３ｈ）と、端子金具２４ａの１対の突起部２４ｐ（頂点２４ｈ）とは、左右反転した位置に配置されるが、端子金具２３ａの１対の突起部２３ｐ（頂点２３ｈ）が軸線Ｏ方向に異なる位置にずれているため、端子金具２４ａの１対の突起部２４ｐ（頂点２４ｈ）も、軸線Ｏ方向に沿って端子金具２３ａと反対側に位置する。従って、端子金具２３ａの１対の突起部２３ｐ（頂点２３ｈ）は端子金具２４ａの突起部２４ｐ（頂点２４ｈ）には当接せず、端子金具２４ａの先端部の表面に当接することになる。同様に、端子金具２４ａの１対の突起部２４ｐ（頂点２４ｈ）も、端子金具２３ａの先端部の表面に当接する。
このように、図９においても、端子金具２３ａは自身の幅方向の２箇所（各頂点２３ｈ）にて、相手となる端子金具２４ａに当接するので、対向する端子金具２３ａ、２４ａ同士がずれた方向（例えば、ハの字方向）に向くことが無く、略平行となる。その結果、センサ素子１０が端子金具２３ａ、２４ａ間に挿入される際に、端子金具２３ａ、２４ａによって挿入困難となったり、軸ずれを生じて挿入されたりすることを抑制できる。
なお、互いに対向する他の端子金具２３ｂ、２４ｂについても同様である。
又、端子金具２３ａ、２４ａの各突起部２３ｐ、２４ｐ自身は中心線Ｃｅを超えて反対側まで形成されているが、突起部２３ｐ、２４ｐの端部（裾野）付近は頂点２３ｈ、２４ｈより高さが低いので、中心線Ｃｅを超えた部分で突起部２３ｐ、２４ｐが互いに干渉して衝突することはない。 FIG. 9 is a side view (viewed from a direction perpendicular to the direction of the axis O) showing an overlapping state of the terminal fittings 23a and 24a facing each other in a state where the sensor element 10x is not inserted.
In FIG. 9, the terminal fittings 23a and 24a overlap. On the other hand, the pair of protrusions 23p (vertex 23h) of the terminal metal fitting 23a and the pair of protrusions 24p (vertex 24h) of the terminal metal fitting 24a are arranged at positions reversed left and right. Since the pair of protrusions 23p (vertex 23h) are shifted to different positions in the direction of the axis O, the pair of protrusions 24p (vertex 24h) of the terminal fitting 24a is also opposite to the terminal fitting 23a along the axis O direction. Located in. Therefore, the pair of protrusions 23p (vertex 23h) of the terminal fitting 23a does not contact the protrusion 24p (vertex 24h) of the terminal fitting 24a, but contacts the surface of the tip end of the terminal fitting 24a. Similarly, the pair of protrusions 24p (vertex 24h) of the terminal fitting 24a also abuts on the surface of the tip of the terminal fitting 23a.
Thus, also in FIG. 9, the terminal fittings 23a abut against the mating terminal fitting 24a at two locations (each vertex 23h) in the width direction of the terminal fitting 23a, so that the opposing terminal fittings 23a and 24a are displaced from each other. It does not face in the direction (for example, the C-shaped direction) and is substantially parallel. As a result, when the sensor element 10 is inserted between the terminal fittings 23a and 24a, it is possible to suppress the insertion of the sensor fitting 10 due to the terminal fittings 23a and 24a or the occurrence of an axial shift.
The same applies to the other terminal fittings 23b and 24b facing each other.
In addition, the protrusions 23p and 24p of the terminal fittings 23a and 24a themselves are formed to the opposite side beyond the center line Ce, but the vicinity of the ends (skirts) of the protrusions 23p and 24p is higher than the vertices 23h and 24h. Therefore, the protrusions 23p and 24p do not interfere with each other and collide with each other beyond the center line Ce.

本発明は上記実施形態に限定されず、本発明の思想と範囲に含まれる様々な変形及び均等物に及ぶことはいうまでもない。
例えば、端子金具は、自身の中心線を挟むように頂点を有する内側突起部及び外側突起部を１個以上有していればよく、突起部を合計で３個以上有していてもよい。この場合、例えば端子金具の中心線よりずれた一方の側（例えば内側）において、突起部が幅方向に２個以上並んでもよく、この側にて突起部が軸線方向に２個以上並んでもよい。
又、ガスセンサとしては、酸素センサ、全領域ガスセンサの他、ＮＯｘセンサが挙げられる。 It goes without saying that the present invention is not limited to the above-described embodiment, but extends to various modifications and equivalents included in the spirit and scope of the present invention.
For example, the terminal fitting only needs to have one or more inner protrusions and outer protrusions having apexes so as to sandwich the center line thereof, and may have a total of three or more protrusions. In this case, for example, two or more protrusions may be arranged in the width direction on one side (for example, the inner side) shifted from the center line of the terminal fitting, and two or more protrusions may be arranged in the axial direction on this side. .
Examples of the gas sensor include an oxygen sensor, a full range gas sensor, and a NOx sensor.

１０，１０ｘセンサ素子
１０Ａセンサ素子の一方の主面
１０Ｂセンサ素子の他方の主面
１１ａ、１１ｂ、１２ａ、１２ｂ電極パッド
２１ａ、２１ｂ、２２ａ、２２ｂ、２３ａ、２３ｂ、２４ａ、２４ｂ、２５端子金具
２１ａ、２１ｂ、２２ａ、２２ｂ、２３ａ、２３ｂ、２４ａ、２４ｂ外側端子金具
２１ｐ１、２２ｐ１、２３ｐ１、２４ｐ１内側突起部
２１ｐ２、２２ｐ２、２３ｐ２、２４ｐ２外側突起部
２１ｈ、２２ｈ、２３ｈ、２４ｈ端子金具の頂点
２００ガスセンサ
Ｏ軸線
Ｃｅ端子金具の中心線
Ｇ_２、Ｇ_４最も離れた２つの電極パッドの外縁間の最大間隔
Ｇ_１、Ｇ_３外側端子金具の幅方向中心線同士を結ぶ最小距離
ｄ_１突起部の先端縁から頂点までの距離
ｄ_２頂点から突起部の後端縁までの距離 10, 10x Sensor element 10A One main surface of sensor element 10B Other main surface of sensor element 11a, 11b, 12a, 12b Electrode pad 21a, 21b, 22a, 22b, 23a, 23b, 24a, 24b, 25 Terminal fitting 21a , 21b, 22a, 22b, 23a, 23b, 24a, 24b Outer terminal fitting 21p1, 22p1, 23p1, 24p1 Inner protrusion 21p2, 22p2, 23p2, 24p2 Outer protrusion 21h, 22h, 23h, 24h Apex of terminal fitting 200 Gas sensor O Axis line Ce Terminal metal center line G ₂ , G ₄ Maximum distance between the outer edges of the two most distant electrode pads G ₁ , G ₃ Minimum distance connecting the center lines in the width direction of the outer terminal metal parts d ₁ Tip of protrusion Distance from edge to vertex d ₂ Distance from vertex to rear edge of protrusion

Claims

A sensor element having a plurality of electrode pads extending in the axial direction and having a plate shape having opposing main surfaces and arranged in the width direction on the rear end side of at least one main surface;
Terminal fittings respectively connected to the electrode pads;
A gas sensor comprising:
In the width direction of the main surface, the center line passing through the center in the width direction of the outer terminal fitting connected to each of the two electrode pads, rather than the maximum distance between the two outermost outer edges of the plurality of electrode pads The minimum distance between each other is wide,
The gas sensor in which the outer terminal fitting has an inner protrusion and an outer protrusion having apexes so as to separate the center line, and the apexes of the inner protrusions are connected to the two electrode pads.

The two electrode pads and the outer terminal fitting are respectively provided on the other main surface of the sensor element so as to face each other with the sensor element interposed therebetween,
In the state where the sensor element is not inserted between the terminal fittings, for each of the two outer terminal fittings facing each other, the inner protruding portion and the outer protruding portion provided on one outer terminal fitting are the other of the other The gas sensor according to claim 1, wherein the gas sensor is in contact with the terminal fitting.

The distance from the tip edge to the vertex is longer than the distance from the vertex to the rear edge of at least one of the inner projection and the outer projection as viewed in the axial direction. Gas sensor.