JPH1144669A - Sensor covered with cover - Google Patents

Sensor covered with cover

Info

Publication number
JPH1144669A
JPH1144669A JP9202981A JP20298197A JPH1144669A JP H1144669 A JPH1144669 A JP H1144669A JP 9202981 A JP9202981 A JP 9202981A JP 20298197 A JP20298197 A JP 20298197A JP H1144669 A JPH1144669 A JP H1144669A
Authority
JP
Japan
Prior art keywords
cover
hole
water
outer cover
gap
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP9202981A
Other languages
Japanese (ja)
Inventor
Satoko Inuzuka
郷子 犬塚
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toyota Motor Corp
Original Assignee
Toyota Motor Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Toyota Motor Corp filed Critical Toyota Motor Corp
Priority to JP9202981A priority Critical patent/JPH1144669A/en
Publication of JPH1144669A publication Critical patent/JPH1144669A/en
Pending legal-status Critical Current

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  • Measuring Oxygen Concentration In Cells (AREA)
  • Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)
  • Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)

Abstract

PROBLEM TO BE SOLVED: To obtain a sensor which can restrain water from creeping into a protective cover by a method wherein protrusions which protrude toward the outside of the protective cover are formed in the edge part of a through hole at least on one layer of the protective cover. SOLUTION: An oxygen sensor 1 is provided with a protective cover 3 which covers a detection part 2. The protective cover 3 is provided with a cylindrical inner cover 4 and with a cylindrical outer cover 5. A gap 7 is formed between the inner cover 4 and the outer cover 5. Inner through holes 41 and outer through holes 51 are formed nearly in the whole regions in the circumferential wall of the inner cover 4 and in the circumferential wall of the outer cover 5 in such a way that they are dispersed alternately at prescribed intervals. In addition, first protrusions 53 and second protrusions 43 are formed respectively at the outer through holes 51 and the inner through holes 41. Then, the first protrusions 53 act as barriers to water which creeps into the outer cover 5, and the water is hard to creep into the outer cover 5 from the outer through holes 51. Consequently, it is possible to restrain the water from creeping into the gap 7 between the the inner cover 4 and the outer cover 5. Even when the water creeps into the gap 7, the second protrusions 43 act as barriers to the water which creeps into the inner cover 4, and the life of the detection part 2 can be made long.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は、測定用のガスが通
過する透孔をもつ保護カバーを備えたカバー被覆式セン
サに関する。本発明は例えば酸素濃度センサ等のガスセ
ンサに適用できる。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cover-covered sensor provided with a protective cover having a through hole through which a gas for measurement passes. The present invention can be applied to a gas sensor such as an oxygen concentration sensor.

【0002】[0002]

【従来の技術】カバー被覆式センサの従来技術につい
て、酸素濃度センサを例にとって説明する。図11から
理解できるように、酸素濃度センサは、検知部100
と、検知部100を覆う保護カバー200とを具備して
いる。保護カバー200は、内カバー201と外カバー
205とで二重構造とされている。
2. Description of the Related Art The prior art of a cover-covered sensor will be described by taking an oxygen concentration sensor as an example. As can be understood from FIG. 11, the oxygen concentration sensor
And a protective cover 200 that covers the detection unit 100. The protection cover 200 has a double structure including an inner cover 201 and an outer cover 205.

【0003】そして内カバー201の透孔202と外カ
バー205の透孔206とは、互い違いに配置されてい
る。これにより検知部100に対する保護性を高め、排
気ガスに含まれる被毒成分が検知部100に直接当たる
ことを抑制している。
The through holes 202 of the inner cover 201 and the through holes 206 of the outer cover 205 are alternately arranged. This enhances the protection of the detection unit 100 and suppresses poisoning components contained in the exhaust gas from directly hitting the detection unit 100.

【0004】[0004]

【発明が解決しようとする課題】上記したセンサでは、
内カバー201と外カバー205との間の隙間208に
水が入ることがある。殊に、内カバー201と外カバー
205とが接近しており、内カバー201と外カバー2
05との間の隙間208の隙間幅が微小である場合に
は、毛細管現象等により隙間208に水が入り易い。
In the above-mentioned sensor,
Water may enter the gap 208 between the inner cover 201 and the outer cover 205. In particular, the inner cover 201 and the outer cover 205 are close to each other, and the inner cover 201 and the outer cover 2
When the gap width between the gap 208 and the gap 05 is very small, water easily enters the gap 208 due to a capillary phenomenon or the like.

【0005】このように保護カバー200内に水が入る
ことは、酸素濃度センサの長寿命化等の観点から、あま
り好ましくない。本発明は上記した実情に鑑みなされた
ものであり、その課題は、保護カバー内に水が入るのを
抑制するのに有利なカバー被覆式センサを提供するにあ
る。
It is not preferable that water enters the protective cover 200 from the viewpoint of extending the life of the oxygen concentration sensor. The present invention has been made in view of the above circumstances, and an object thereof is to provide a cover-covered sensor that is advantageous for suppressing entry of water into a protective cover.

【0006】[0006]

【課題を解決するための手段】本発明者は、透孔をもつ
保護カバーをもつ方式のカバー被覆式センサにおいて鋭
意開発を進め、保護カバーのうち透孔の縁部に、保護カ
バーの外方に向かう方向に突出する突部を形成すれば、
水の入り込みを抑制し易いことを知見し、本発明に係る
カバー被覆式センサを開発した。
Means for Solving the Problems The present inventor has been diligently developing a cover-covered sensor of a type having a protective cover having a through hole, and has provided an outer peripheral portion of the protective cover at an edge of the through hole in the protective cover. If you form a projection that projects in the direction toward
Knowing that it is easy to suppress the entry of water, a cover-covered sensor according to the present invention was developed.

【0007】本発明に係るカバー被覆式センサは、検知
部と、測定用のガスが透過する透孔をもつ少なくとも1
重の保護カバーとを具備するカバー被覆式センサにおい
て、保護カバーのうち少なくとも1重において、透孔の
縁部には、保護カバーの外方に向かう方向に突出する突
部が形成されていることを特徴とするものである。
[0007] A cover-covered sensor according to the present invention has at least one detecting portion and at least one through hole through which a measurement gas passes.
In a cover-covered sensor having a heavy protective cover, at least one of the protective covers has a projection formed at an edge of the through hole in a direction toward the outside of the protective cover. It is characterized by the following.

【0008】[0008]

【発明の実施の形態】本発明に係るセンサでは、測定用
のガスが透過する透孔をもつ保護カバーが設けられてい
る。保護カバーは1重でも、2重でも、3重でも良い。
保護カバーの透孔の縁部には、外方に向かう方向に突出
する突部が形成されている。突部は、透孔の縁部を1周
するように形成できる。突部は、1重でも良いし2重で
も良い。突部は、透孔の縁部自身を曲成して形成する形
態でも良いし、或いは、別体のものを透孔の縁部に固着
する形態でも良い。突部の突出量はセンサの種類、セン
サの使用環境等に応じて適宜選択できるが、例えば0.
2〜5mm程度にできる。
DESCRIPTION OF THE PREFERRED EMBODIMENTS A sensor according to the present invention is provided with a protective cover having a through hole through which a gas for measurement passes. The protective cover may be single, double or triple.
At the edge of the through hole of the protective cover, a projection is formed that projects outward. The protrusion can be formed so as to make one round around the edge of the through hole. The projection may be single or double. The protrusion may be formed by bending the edge of the through hole itself, or may be formed by fixing a separate body to the edge of the through hole. The protrusion amount of the protrusion can be appropriately selected according to the type of the sensor, the use environment of the sensor, and the like.
It can be about 2 to 5 mm.

【0009】保護カバーが内カバーと外カバーとを備え
ている場合には、内カバーと外カバーの少なくとも一方
に形成されている透孔に、突部を形成することができ
る。
When the protective cover has an inner cover and an outer cover, a projection can be formed in a through hole formed in at least one of the inner cover and the outer cover.

【0010】[0010]

【実施例】以下、本発明の実施例を図面を参照して説明
する。 (実施例の構成)本実施例は、車両等の内燃機関から排
出される排気ガスの酸素濃度を測定するために、排気系
通路に装備される酸素濃度センサに適用した場合であ
る。
Embodiments of the present invention will be described below with reference to the drawings. (Structure of Embodiment) This embodiment is a case where the present invention is applied to an oxygen concentration sensor provided in an exhaust system passage for measuring the oxygen concentration of exhaust gas discharged from an internal combustion engine of a vehicle or the like.

【0011】図1から理解できるように、酸素濃度セン
サ1は、丸棒状をなす検知部2と、検知部2を覆う保護
カバー3とを備えている。保護カバー3は、検知部2を
覆う筒形状をなす内カバー4と、内カバー4を覆う筒形
状をなす外カバー5とを備えている。外カバー5及び内
カバー4は、共に断面円形状をなす。外カバー5及び内
カバー4は、金属製(例えば炭素鋼系、合金鋼系、ステ
ンレス鋼系)であり、実質的に同軸的な配置とされてい
る。外カバー5及び検知部2はフランジ盤6に保持され
ている。
As can be understood from FIG. 1, the oxygen concentration sensor 1 includes a round bar-shaped detection unit 2 and a protective cover 3 that covers the detection unit 2. The protection cover 3 includes a cylindrical inner cover 4 that covers the detection unit 2 and a cylindrical outer cover 5 that covers the inner cover 4. The outer cover 5 and the inner cover 4 both have a circular cross section. The outer cover 5 and the inner cover 4 are made of metal (for example, carbon steel, alloy steel, or stainless steel) and are arranged substantially coaxially. The outer cover 5 and the detection unit 2 are held by a flange disk 6.

【0012】検知部2に対する被毒性を抑制するため、
また酸素濃度センサ1の径方向における小型化を図るた
め等の理由により、外カバー5の周壁と内カバー4の周
壁とは、ガス透過性を確保しつつ互いに接近している。
従って、外カバー5と内カバー4との間には隙間7が形
成されている。内燃機関の排気ポートから排出された測
定用のガスが隙間7を通る。
In order to suppress the poisoning of the detection unit 2,
Further, for reasons such as reducing the size of the oxygen concentration sensor 1 in the radial direction, the peripheral wall of the outer cover 5 and the peripheral wall of the inner cover 4 are close to each other while ensuring gas permeability.
Therefore, a gap 7 is formed between the outer cover 5 and the inner cover 4. The gas for measurement discharged from the exhaust port of the internal combustion engine passes through the gap 7.

【0013】隙間7の隙間幅Xは、微小とされている。
隙間7の隙間幅Xは適宜選択できるものの、本実施例で
は0.5〜10mm程度、1〜3mm程度とされてい
る。外カバー5のうち、ガスの上流UP に対面する領域
は、上流対面領域58とされている。外カバー5のう
ち、ガスの下流dO に対面する領域は、下流対面領域5
9とされている。
The gap width X of the gap 7 is small.
Although the gap width X of the gap 7 can be appropriately selected, in the present embodiment, it is about 0.5 to 10 mm and about 1 to 3 mm. Of the outer cover 5, the region facing the upstream U P of the gas is an upstream facing region 58. In the outer cover 5, a region facing the downstream d O of the gas is a downstream facing region 5.
9 is set.

【0014】上流対面領域58及び下流対面領域59を
含む外カバー5の周壁の略全域には、外透孔51が多数
個所定の間隔で分散して形成されている。内カバー4の
周壁の略全域にも、同様に内透孔41が多数個所定の間
隔で分散して形成されている。外透孔51と内透孔41
とは互い違いに形成されており、両者が重ならならない
ようにされている。検知部2における被毒を抑制するた
めである。
A large number of outer through holes 51 are formed at predetermined intervals in substantially the entire peripheral wall of the outer cover 5 including the upstream facing area 58 and the downstream facing area 59. Similarly, a plurality of inner through-holes 41 are similarly formed at predetermined intervals in substantially the entire peripheral wall of the inner cover 4. Outer hole 51 and inner hole 41
Are formed alternately with each other so that they do not overlap. This is for suppressing the poisoning in the detection unit 2.

【0015】内透孔41と外透孔51は共に円形状とさ
れている。図1に示すように、内カバー4の底部4cと
外カバー5の底部5cとは重合している。さて本実施例
においては、外透孔51には、外カバー5の半径方向に
おける外方に向かう方向に突出する第1の突部53が形
成されている。内透孔41には、内カバー4の半径方向
における外方に向かう方向に突出する第2の突部43が
形成されている。
The inner through hole 41 and the outer through hole 51 are both circular. As shown in FIG. 1, the bottom 4c of the inner cover 4 and the bottom 5c of the outer cover 5 overlap. In the present embodiment, a first projection 53 projecting outward in the radial direction of the outer cover 5 is formed in the outer through-hole 51. The inner through hole 41 is formed with a second protrusion 43 that protrudes outward in the radial direction of the inner cover 4.

【0016】第1の突部53は、外透孔51の回りを1
周している。第2の突部43は、内透孔41の回りを環
状に1周している。図5(A)において寸法関係の1例
を示す。この場合には、隣設する外透孔51の縁間の距
離Aは、2〜2.5mm程度とされている。外カバー5
の外壁面5eに対する第1の突部53の突出量Bは、
0.4〜0.5mm程度とされている。外透孔51の孔
径Cは、2〜2.2mm程度とされている。第1の突部
53の先端間の孔径Dは、1.8〜2.0mm程度とさ
れている。
The first projection 53 extends around the outer through hole 51 by one.
Is circling. The second protrusion 43 makes one round around the inner through hole 41. FIG. 5A shows an example of the dimensional relationship. In this case, the distance A between the edges of the adjacent outer through holes 51 is about 2 to 2.5 mm. Outer cover 5
The protrusion amount B of the first protrusion 53 with respect to the outer wall surface 5e of
It is about 0.4 to 0.5 mm. The hole diameter C of the outer through-hole 51 is about 2 to 2.2 mm. The hole diameter D between the tips of the first protrusions 53 is about 1.8 to 2.0 mm.

【0017】本実施例では例えば、(C−D)≦0.1
〜2〔mm〕、殊に(C−D)≦0.2〔mm〕の関係
に規定できる。但し、上記A〜Dは上記した寸法に限定
されるものではない。図5(A)〜(C)は、外カバー
5の外透孔51の縁に形成した第1の突部53の形態の
代表例の断面を模式的に示す。図5(A)に示す例で
は、第1の突部53は、半径方向の外方つまり矢印W1
方向に向かうにつれて内径が次第に小さくなるアール部
53kと、矢印W1方向に向かうにつれて内径が大きく
なる傾斜端面部53mとをもつ。アール部53kは、第
1の突部53の根元に形成されている。
In this embodiment, for example, (CD) ≦ 0.1
22 [mm], particularly (CD) ≦ 0.2 [mm]. However, A to D are not limited to the dimensions described above. FIGS. 5A to 5C schematically show a cross section of a typical example of the form of the first protrusion 53 formed on the edge of the outer through hole 51 of the outer cover 5. In the example shown in FIG. 5A, the first protrusion 53 is located radially outward, that is, the arrow W1.
It has a rounded portion 53k whose inner diameter becomes gradually smaller toward the direction and an inclined end face portion 53m whose inner diameter becomes larger toward the direction of the arrow W1. The round portion 53k is formed at the base of the first protrusion 53.

【0018】図5(B)に示す例では、第1の突部53
は、矢印W1方向に向かうにつれて内径が次第に小さく
なるアール部53kと、外カバー5の外壁面5eに実質
的に沿う端面部53nとをもつ。図5(C)に示す例で
は、第1の突部53は、矢印W1方向に向かうにつれて
内径が次第に小さくなるアール部53kと、外カバー5
の外周面に実質的に沿う端面部53nとをもち、更に外
カバー5の外壁面5eに対する第1の突部53の突出量
は大きくされている。
In the example shown in FIG. 5B, the first projection 53
Has a rounded portion 53k whose inner diameter gradually decreases in the direction of the arrow W1, and an end surface portion 53n substantially along the outer wall surface 5e of the outer cover 5. In the example shown in FIG. 5 (C), the first protrusion 53 has a rounded portion 53k whose inner diameter gradually decreases as going in the direction of the arrow W1;
And an end surface 53n substantially along the outer peripheral surface of the outer cover 5, and the amount of projection of the first projection 53 with respect to the outer wall surface 5e of the outer cover 5 is further increased.

【0019】内カバー4の内透孔41の縁に形成されて
いる第2の突部43についても同様に、図5(A)〜
(C)に示す形態にできる。図7は製造過程の一例の主
要部を示す。図7では、治具8は、円筒形状の外カバー
5の内部に装入される筒体80と、筒体80に形成され
放射状に指向する多数個の孔81と、各孔81に前進後
退可能に挿入されたポンチ82と、各ポンチ82を求心
方向に付勢可能なコイル状のバネ84と、各ポンチ82
の加圧部82cを加圧する加圧手段83とをもつ。外カ
バー5の外周側には、孔81に対面するダイス孔85を
もつダイス86を配置する。
Similarly, the second protrusion 43 formed on the edge of the inner through-hole 41 of the inner cover 4 is shown in FIGS.
The configuration shown in FIG. FIG. 7 shows a main part of an example of the manufacturing process. In FIG. 7, the jig 8 includes a cylindrical body 80 inserted into the cylindrical outer cover 5, a large number of holes 81 formed in the cylindrical body 80, and a plurality of radially oriented holes 81. A punch 82 that is inserted so as to be capable of being inserted, a coiled spring 84 that can bias each punch 82 in a centripetal direction,
And a pressurizing means 83 for pressurizing the pressurizing portion 82c. A die 86 having a die hole 85 facing the hole 81 is arranged on the outer peripheral side of the outer cover 5.

【0020】筒体80の中央孔80uに嵌合された加圧
手段83が軸長方向に沿ってつまり矢印W3方向に押し
出されると、加圧手段83の端部の周囲に形成したテー
パ面83hがポンチ82の加圧部82cを強圧し、これ
によりバネ84を弾性収縮させつつ、孔81内の各ポン
チ82は放射方向に沿ってつまり矢印W4方向に押し出
され、外カバー5の周壁に外透孔51が形成される。
When the pressing means 83 fitted in the central hole 80u of the cylindrical body 80 is pushed out along the axial length direction, that is, in the direction of the arrow W3, a tapered surface 83h formed around the end of the pressing means 83 Strongly presses the pressurizing portion 82c of the punch 82, thereby elastically contracting the spring 84, while each punch 82 in the hole 81 is pushed out in the radial direction, that is, in the direction of the arrow W4. A through hole 51 is formed.

【0021】その後、ダイス86を別のもの(ダイス孔
85の口径が増加したもの)に交換すると共に、治具8
と別のものと交換し、その別の治具のポンチを放射方向
に押し出せば、外透孔51の縁部が爪状に径外側に曲成
され、これにより外透孔51の縁部に第1の突部53が
曲成される。内カバー4の内透孔41の縁に形成した第
2の突部43についても、この場合と同様に形成でき
る。
After that, the die 86 is replaced with another one (in which the diameter of the die hole 85 is increased) and the jig 8 is replaced.
When the punch of the other jig is pushed out in the radial direction, the edge of the outer through-hole 51 is bent radially outward in a claw shape, thereby forming the edge of the outer through-hole 51. The first projection 53 is bent. The second protrusion 43 formed on the edge of the inner through hole 41 of the inner cover 4 can be formed in the same manner as in this case.

【0022】図9は別列の主要部を示す。この例の場合
には、図9(A)から理解できるように、外透孔51と
なる貫通孔51pを予め形成した平板9をダイス90に
セットする。その状態でポンチ92を貫通孔51pに挿
入し、これにより貫通孔51pの縁部を曲成し、環状の
第1の突部53を形成するバーリング加工を行う。その
後、その平板9を円筒形状に曲成して外カバー5とす
る。前記した底部5cは溶接等で外カバー5に結合す
る。
FIG. 9 shows a main part of another row. In the case of this example, as can be understood from FIG. 9A, the flat plate 9 in which the through-hole 51p to be the outer through-hole 51 is formed in advance is set in the die 90. In this state, the punch 92 is inserted into the through-hole 51p, whereby the edge of the through-hole 51p is bent, and a burring process for forming the annular first protrusion 53 is performed. Thereafter, the flat plate 9 is bent into a cylindrical shape to form the outer cover 5. The bottom 5c is connected to the outer cover 5 by welding or the like.

【0023】内カバー4の内透孔41の縁に形成した第
2の突部43についても、この場合と同様に形成でき
る。図10は、本実施例に係る酸素濃度センサ1を車両
の排気系通路に装備している状態を模式的に示す。酸素
濃度センサ1のフランジ盤6が排気系通路F1の排気管
F2に固定されている。排気系通路F1を流れる高温の
排気ガスは、図1から理解できるように、外カバー5の
外透孔51、内カバー4の内透孔41を介して検知部2
に至る。そして排気ガス中の酸素濃度の測定が行われ
る。
The second protrusion 43 formed on the edge of the inner through hole 41 of the inner cover 4 can be formed in the same manner as in this case. FIG. 10 schematically shows a state in which the oxygen concentration sensor 1 according to the present embodiment is provided in an exhaust passage of a vehicle. A flange disk 6 of the oxygen concentration sensor 1 is fixed to an exhaust pipe F2 of an exhaust system passage F1. As can be understood from FIG. 1, the high-temperature exhaust gas flowing through the exhaust system passage F1 passes through the outer through-hole 51 of the outer cover 5 and the inner through-hole 41 of the inner cover 4 to detect the detection unit 2.
Leads to. Then, the measurement of the oxygen concentration in the exhaust gas is performed.

【0024】(実施例の効果)外カバー5の外透孔51
の縁部に第1の突部53が形成されている本実施例によ
れば、第1の突部53が、外カバー5の内部に進入する
水に対する障壁となる。よって外透孔51から外カバー
5の内部に水が進入し難い。このように外カバー5の外
透孔51には第1の突部53が形成されているため、外
透孔51の孔径が適当なサイズであれば、外カバー5の
外透孔51に進入せんとする水は、外透孔51におい
て、表面張力により水膜Mwを形成し易くなる(図4参
照)。この意味においても、外カバー5の内部に水が進
入し難い。
(Effects of Embodiment) Outer through holes 51 of outer cover 5
According to the present embodiment in which the first protrusion 53 is formed at the edge of the outer cover 5, the first protrusion 53 serves as a barrier against water entering the inside of the outer cover 5. Therefore, it is difficult for water to enter the inside of the outer cover 5 from the outer through hole 51. Since the first protrusion 53 is formed in the outer through hole 51 of the outer cover 5 as described above, if the outer through hole 51 has an appropriate hole diameter, it enters the outer through hole 51 of the outer cover 5. The water to be removed easily forms a water film Mw in the outer through-hole 51 due to surface tension (see FIG. 4). In this sense, it is difficult for water to enter the inside of the outer cover 5.

【0025】従って本実施例では、外カバー5の内部、
つまり外カバー5と内カバー4との間の隙間7に水が入
ることを抑制するのに有利である。従って検知部2の長
寿命化、良好なセンシングに有利である。仮に、隙間7
に水が入ったとしても、内カバー4の内透孔41の縁部
にも第2の突部43が形成されているため、第2の突部
43が、内カバー4の内部に進入する水に対する障壁と
なる。よって、内透孔41から内カバー4の内部に水が
進入することは、抑制される。従って検知部2の長寿命
化、良好なセンシングに一層有利である。
Therefore, in this embodiment, the inside of the outer cover 5
That is, it is advantageous to prevent water from entering the gap 7 between the outer cover 5 and the inner cover 4. Therefore, it is advantageous for prolonging the life of the detection unit 2 and for good sensing. If the gap 7
Even if water enters, the second protrusion 43 enters the inside of the inner cover 4 because the second protrusion 43 is also formed at the edge of the inner through hole 41 of the inner cover 4. It becomes a barrier to water. Therefore, the entry of water into the inside of the inner cover 4 from the inner through-hole 41 is suppressed. Therefore, it is more advantageous to extend the life of the detection unit 2 and to perform good sensing.

【0026】また図6(A)は、外カバー5の内部に入
った水が多い場合の1例を概念的に示す。図6(B)
は、外カバー5の内部に入った水が少ない場合の1例を
概念的に示す。図6(A)(B)から理解できるよう
に、本実施例によれば、外カバー5の内部に水が入った
場合であっても、外透孔51付近の水Mxは環状の第1
の突部53の内面壁53xに濡れ易くなる。従って隙間
7から外方に排出させ易くなる。
FIG. 6A conceptually shows an example in which a large amount of water has entered the inside of the outer cover 5. FIG. 6 (B)
Fig. 4 conceptually shows an example in which the amount of water entering the inside of the outer cover 5 is small. As can be understood from FIGS. 6A and 6B, according to the present embodiment, even when water enters the inside of the outer cover 5, the water Mx near the outer through-hole 51 is the first annular water.
Of the inner wall 53x of the projection 53 of the first embodiment. Therefore, it is easy to discharge outward from the gap 7.

【0027】また図3は、外カバー5内の隙間7に水が
入った場合の1例の横断面を示す。この場合であって
も、上流Upからのガスが外カバー5の外透孔51から
隙間7に進入し、そのガスによって、図3に示すように
隙間7内の水Mxは矢印W7方向に押し出される。この
とき内カバー4の内透孔41には第2の突部43が形成
されているため、内透孔41に水は入り難い。
FIG. 3 shows a cross section of an example when water enters the gap 7 in the outer cover 5. Even in this case, gas from the upstream Up enters the gap 7 through the outer through hole 51 of the outer cover 5, and the gas pushes water Mx in the gap 7 in the direction of the arrow W7 as shown in FIG. It is. At this time, since the second protrusion 43 is formed in the inner through hole 41 of the inner cover 4, it is difficult for water to enter the inner through hole 41.

【0028】更に外カバー5のうち下流対面領域59の
外透孔51には第1の突部53が環状に形成されてお
り、第1の突部53の根元には前述したようにアール部
53k(図5参照)が形成されている。アール部53k
には、外カバー5の内部から外部に向かう際の水案内作
用を期待できる。よって、水の排出性の一層の向上に有
利である。
Further, a first projection 53 is formed annularly in the outer through-hole 51 in the downstream facing area 59 of the outer cover 5, and the first projection 53 is formed at the root thereof as described above. 53k (see FIG. 5) are formed. 53k
In addition, a water guiding action when going from the inside of the outer cover 5 to the outside can be expected. Therefore, it is advantageous for further improving the water dischargeability.

【0029】加えて本実施例では、外カバー5の外透孔
51の縁には第1の突部53が曲成されているため、第
1の突部53による補強リブ作用を期待できる。従って
外カバー5の外透孔51付近の強化に有利である。内カ
バー4における第2の突部43についても同様である。
故に、軽量化等のために外カバー5や内カバー4の肉厚
が薄い場合であっても、有利である。
In addition, in this embodiment, since the first protrusion 53 is bent at the edge of the outer through hole 51 of the outer cover 5, the reinforcing rib function by the first protrusion 53 can be expected. Therefore, it is advantageous in strengthening the vicinity of the outer through hole 51 of the outer cover 5. The same applies to the second protrusion 43 of the inner cover 4.
Therefore, it is advantageous even when the outer cover 5 and the inner cover 4 are thin for weight reduction or the like.

【0030】(その他)上記した例は、車両に搭載され
る酸素濃度センサに適用した例であるが、これに限ら
ず、保護カバーを備えている他のガスセンサ、湿度セン
サ、温度センサ、圧力センサなど、水が入るおそれがあ
る環境で使用されるセンサ類に広く適用できる。
(Others) The above example is an example applied to an oxygen concentration sensor mounted on a vehicle. However, the present invention is not limited to this, and other gas sensors, humidity sensors, temperature sensors, pressure sensors having a protective cover are provided. For example, it can be widely applied to sensors used in an environment where water may enter.

【0031】[0031]

【発明の効果】本発明に係るカバー被覆式センサによれ
ば、保護カバーの透孔の縁部には突部が形成されている
ため、突部が、保護カバーの内部に進入する水に対する
障壁となり、保護カバーの内部に水が進入し難い。保護
カバーが内カバーと外カバーとからなる場合には、内カ
バーの透孔と外カバーの透孔との双方に突部を形成して
おけば、水は一層進入し難い。
According to the cover-covered sensor of the present invention, since the projection is formed at the edge of the through hole of the protection cover, the projection is a barrier against water entering the inside of the protection cover. It is difficult for water to enter the inside of the protective cover. In the case where the protective cover is composed of the inner cover and the outer cover, if the protrusions are formed in both the through-hole of the inner cover and the through-hole of the outer cover, water is more difficult to enter.

【0032】更に保護カバーの透孔の孔径が適当なサイ
ズであれば、保護カバーの透孔に進入せんとする水は、
表面張力により水膜を透孔に形成し易くなる。この意味
においても、保護カバーの内部に水が進入し難い。
Further, if the diameter of the through hole of the protective cover is an appropriate size, water that enters the through hole of the protective cover will
The surface tension makes it easier to form a water film on the through-hole. In this sense, it is difficult for water to enter the inside of the protective cover.

【図面の簡単な説明】[Brief description of the drawings]

【図1】酸素濃度センサを模式的に示す縦断面図であ
る。
FIG. 1 is a longitudinal sectional view schematically showing an oxygen concentration sensor.

【図2】酸素濃度センサを模式的に示す横断面図であ
る。
FIG. 2 is a cross-sectional view schematically showing an oxygen concentration sensor.

【図3】水が隙間に入った状態の酸素濃度センサを模式
的に示す横断面図である。
FIG. 3 is a cross-sectional view schematically showing the oxygen concentration sensor in a state where water has entered a gap.

【図4】水が外カバーに付着した状態の酸素濃度センサ
を模式的に示す縦断面図である。
FIG. 4 is a longitudinal sectional view schematically showing an oxygen concentration sensor in a state where water adheres to an outer cover.

【図5】外カバーの外透孔付近を拡大して示す縦断面図
である。
FIG. 5 is an enlarged longitudinal sectional view showing the vicinity of an outer through hole of an outer cover.

【図6】外カバーのうち下流対面領域に形成されている
外透孔付近を拡大して示す縦断面図である。
FIG. 6 is an enlarged longitudinal sectional view showing the vicinity of an outer through-hole formed in a downstream facing area of the outer cover.

【図7】治具を用いている状態を模式的に示す平面図で
ある。
FIG. 7 is a plan view schematically showing a state in which a jig is used.

【図8】治具を用いている状態を拡大して模式的に示す
断面図である。
FIG. 8 is an enlarged cross-sectional view schematically showing a state in which a jig is used.

【図9】外カバーに第1の突部を形成する別例に係る過
程を模式的に示す工程図である。
FIG. 9 is a process diagram schematically showing a process according to another example of forming the first protrusion on the outer cover.

【図10】酸素濃度センサを排気系通路に配置している
状態を模式的に示す構成図である。
FIG. 10 is a configuration diagram schematically showing a state where an oxygen concentration sensor is arranged in an exhaust passage.

【図11】従来技術に係る酸素濃度センサを模式的に示
す縦断面図である。
FIG. 11 is a longitudinal sectional view schematically showing an oxygen concentration sensor according to a conventional technique.

【符号の説明】[Explanation of symbols]

図中、1は酸素濃度センサ、3は保護カバー、4は内カ
バー、41は内透孔、43は第2の突部、5は外カバ
ー、51は外透孔、53は第1の突部、7は隙間を示
す。
In the figure, 1 is an oxygen concentration sensor, 3 is a protective cover, 4 is an inner cover, 41 is an inner through hole, 43 is a second projection, 5 is an outer cover, 51 is an outer through hole, and 53 is a first projection. The part 7 indicates a gap.

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】検知部と、測定用のガスが透過する透孔を
もつ少なくとも1重の保護カバーとを具備するカバー被
覆式センサにおいて、 前記保護カバーのうち少なくとも1重において、前記透
孔の縁部には、保護カバーの外方に向かう方向に突出す
る突部が形成されていることを特徴とするカバー被覆式
センサ。
1. A cover-covered sensor comprising a detection unit and at least a single protective cover having a through hole through which a gas for measurement passes, wherein at least one of the protective covers has the through hole. A cover-covered sensor, wherein a projection is formed at an edge of the protection cover so as to project outward.
JP9202981A 1997-07-29 1997-07-29 Sensor covered with cover Pending JPH1144669A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP9202981A JPH1144669A (en) 1997-07-29 1997-07-29 Sensor covered with cover

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP9202981A JPH1144669A (en) 1997-07-29 1997-07-29 Sensor covered with cover

Publications (1)

Publication Number Publication Date
JPH1144669A true JPH1144669A (en) 1999-02-16

Family

ID=16466364

Family Applications (1)

Application Number Title Priority Date Filing Date
JP9202981A Pending JPH1144669A (en) 1997-07-29 1997-07-29 Sensor covered with cover

Country Status (1)

Country Link
JP (1) JPH1144669A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1279957A2 (en) * 2001-07-27 2003-01-29 Denso Corporation Gas sensor with rapid response time
JP2006343104A (en) * 2005-06-07 2006-12-21 Honda Motor Co Ltd Gas sensor
JP2014025726A (en) * 2012-07-24 2014-02-06 Mitsubishi Motors Corp Protective cover structure for gas sensor
TWI679410B (en) * 2017-12-15 2019-12-11 財團法人工業技術研究院 Embedding sensor module and sensing device
US10895561B2 (en) 2017-12-15 2021-01-19 Industrial Technology Research Institute Embedded sensor module and sensing device

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1279957A2 (en) * 2001-07-27 2003-01-29 Denso Corporation Gas sensor with rapid response time
JP2003107033A (en) * 2001-07-27 2003-04-09 Denso Corp Gas sensor
EP1279957A3 (en) * 2001-07-27 2004-04-14 Denso Corporation Gas sensor with rapid response time
US6948353B2 (en) 2001-07-27 2005-09-27 Denso Corporation Quick response structure of gas sensor
JP2006343104A (en) * 2005-06-07 2006-12-21 Honda Motor Co Ltd Gas sensor
JP4695441B2 (en) * 2005-06-07 2011-06-08 本田技研工業株式会社 Gas sensor
JP2014025726A (en) * 2012-07-24 2014-02-06 Mitsubishi Motors Corp Protective cover structure for gas sensor
TWI679410B (en) * 2017-12-15 2019-12-11 財團法人工業技術研究院 Embedding sensor module and sensing device
US10895561B2 (en) 2017-12-15 2021-01-19 Industrial Technology Research Institute Embedded sensor module and sensing device

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