JP2005024429A

JP2005024429A - Connection fitting for temperature sensor and manufacturing method for the same

Info

Publication number: JP2005024429A
Application number: JP2003191192A
Authority: JP
Inventors: Takeshi Hanzawa; 剛半沢; Masahiko Nishi; 雅彦西; Masaki Iwatani; 雅樹岩谷; Takaaki Chiyousokabe; 孝昭長曽我部
Original assignee: NGK Spark Plug Co Ltd
Current assignee: Niterra Co Ltd
Priority date: 2003-07-03
Filing date: 2003-07-03
Publication date: 2005-01-27
Anticipated expiration: 2023-07-03
Also published as: JP4369173B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a connection fitting for temperature sensor capable of stabilizing the quality of the temperature sensor and improving reliability and a manufacturing method for the temperature sensor. <P>SOLUTION: A connection metal fitting 16 has a connection part 16c extending in the axial direction and a core wire fixing part 16b is formed at one end of the connection part 16c and a lead wire fixing part 16a is formed at the other end in the axial direction. The core wire fixing part 16b has a cylinder part 16d formed in cylinder shape extending to the axial direction and inserted by the core wire 11 from the tip end side, and a slit 16f formed in the cylinder part 16d and allowing elasticity in radial direction of the cylinder part 16d. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は温度センサ用接続金具及び温度センサの製造方法に関する。本発明の製造方法による温度センサは、車両の排気ガス等の温度を検知する場合に用いて好適である。
【０００２】
【従来の技術】
従来、特許文献１記載の温度センサ用接続金具及び温度センサの製造方法が知られている。この温度センサ用接続金具及び製造方法による温度センサは、ハウジング内に収納され、温度により変化する電気的特性を電気信号としてＭＩケーブルの一対の芯線に出力するサーミスタと、サーミスタからの電気信号をハウジング外に取り出すための一対のリード線と、芯線とリード線とを接続する接続金具とを備えている。そして、リード線は接続金具のリード線固定部にかしめによって固定され、芯線は接続金具の芯線固定部にレーザによって固定されている。なお、ＭＩケーブルはシース芯線とも呼ばれ、筒状の金属パイプと、金属パイプの内側に配置される芯線と、金属パイプと芯線との間に充填される絶縁粉末とを有し、芯線が金属パイプに対して絶縁粉末によって絶縁保持されたものである（ＪＩＳＦ００３１参照）。この温度センサは例えば対象物としての車両の排気通路に取付けられる。この温度センサでは、サーミスタが排気ガスの温度により変化する抵抗値を電気信号としてＭＩケーブルの一対の芯線に出力することから、芯線と接続金具により接続されたリード線によってその電気信号がハウジング外に取り出されることとなる。こうして、この温度センサにより排気ガスの温度が計測され、その温度に応じて車両のエンジン等が制御される。
【０００３】
【特許文献１】
特開２００２−２２１４５１号公報
【０００４】
【発明が解決しようとする課題】
しかし、上記従来の温度センサ用接続金具及び温度センサの製造方法では、温度センサの品質が不安定になり、温度センサの信頼性が低下する虞があった。
【０００５】
つまり、従来では、ＭＩケーブルの芯線の外径よりも大きな内径をもつ芯線固定部を有する接続金具を用意し、この芯線固定部内に遊嵌状に芯線を挿入しつつ、芯線固定部内の所定位置にて芯線の位置決めを行った後、芯線固定部を径方向内側にかしめ（塑性変形させ）、次いでレーザ溶接を行って芯線と芯線固定部とを接続させていた。しかしながら、芯線固定部を塑性変形させることにより、芯線固定部への芯線の保持を行う構成では、この塑性変形（かしめ）を実行する前段階において、芯線を芯線固定部内の所定位置に位置決めしていたとしても、芯線固定部の塑性変形に伴って芯線が位置ずれ（横ずれ）を生じることがある。そして、芯線が芯線固定部内の所定位置から位置ずれを生じた状態でレーザ溶接を行った場合には、予め設定したレーザ光の照射位置に対して芯線が位置ずれを生じてしまっているが故に、強固な溶接が行えずに溶接信頼性が低下してしまう。このように芯線と接続金具（溶接固定部）との溶接信頼性が低いと、接続金具に別途接続されるリード線に対して過度の引張力が作用すると、芯線と溶接固定部との接続状態が不良を起こし易く、適切な電気信号の出力を得ることができなくなってしまう。
【０００６】
本発明は、上記従来の実情に鑑みてなされたものであって、温度センサの品質を安定させ、信頼性を向上させることができる温度センサ用接続金具及び温度センサの製造方法を提供することを解決すべき課題としている。
【０００７】
【課題を解決するための手段】
本発明の温度センサ用接続金具は、ＭＩケーブルの芯線を固定する芯線固定部と、該芯線固定部と一体に形成され、リード線を固定するリード線固定部とを有し、温度センサを構成する温度センサ用接続金具において、
前記芯線固定部及び前記リード線固定部の少なくとも一方は、前記芯線又は前記リード線である線材を自身の内側に配置しつつ、該線材を弾性的に保持可能に構成されていることを特徴とする。
【０００８】
本発明の温度センサ用接続金具では、芯線固定部及びリード線固定部の少なくとも一方は芯線又はリード線である線材を自身の内側に配置しつつ、この線材を弾性的に保持可能に構成されているため、線材を芯線固定部又はリード線固定部に保持させるに際して、芯線固定部又はリード線固定部を塑性変形させる必要がなく、線材を芯線固定部又はリード線固定部の所定位置に装着するだけで、線材が芯線固定部又はリード線固定部の所定の位置からずれることを防止することができる。そして、線材を芯線固定部又はリード線固定部に保持させた後、溶接等により確実に線材を芯線固定部又はリード線固定部に固定することができる。
【０００９】
したがって、本発明の温度センサ用接続金具を用いた温度センサについては、品質を安定させ、信頼性を向上させることができる。また、本発明の温度センサ用接続金具を用いることにより、ＭＩケーブルの芯線とリード線との接続が容易になり、温度センサの製造コストの低廉化を実現することができる。
【００１０】
また、温度センサ用接続金具は、軸方向に延びる連結部を有し、該連結部の先端側に前記芯線固定部が形成され、軸方向の後端側に前記リード線固定部が形成されていることが好ましい。これにより、連結部の両端より芯線及びリード線を芯線固定部及びリード線固定部に保持させることができ、作業性に優れる。
【００１１】
さらに、本発明の温度センサ用接続金具では、前記芯線固定部が前記芯線を自身の内側に配置しつつ、該芯線を弾性的に保持可能に構成されていることが好ましい。芯線は細い上、芯線間の距離が小さいため、芯線を芯線固定部内の所定位置に位置決めした上で位置ずれなくかしめ保持させるのは困難である。その点、芯線固定部が芯線を自身の内側に配置しつつ、この芯線を弾性的に保持可能に構成されていれば、芯線を芯線固定部に保持させた後、溶接により確実に芯線を芯線固定部に固定することができ、温度センサの品質を安定させ、信頼性を向上させる効果が大きい。
【００１２】
また、前記芯線固定部は、軸方向に延びる筒状に形成されて前記芯線を先端側から挿入させる筒部と、該筒部に形成されて該筒部の径方向の弾性を許容するスリットとをもつことが好ましい。これにより、芯線を筒部の先端側から挿入するだけで筒部の弾性力により芯線を保持可能とすることができる。
【００１３】
さらに、前記芯線固定部は、前記筒部の先端側に形成され、先端に向かって内径が拡径する呼込み部をもつことが好ましい。この呼込み部を有することにより、芯線を筒部の内側に容易に挿入することができる。
【００１４】
前記リード線固定部は前記リード線をかしめによって固定可能に構成されていることが好ましい。リード線は撚り線である場合が多く、溶接よりもかしめによって固定する方が適しているからである。
【００１５】
本発明の温度センサの製造方法は、ハウジングと、該ハウジング内に収納され、温度により変化する電気的特性を電気信号としてＭＩケーブルの一対の芯線に出力する感温素子と、該感温素子からの該電気信号を該ハウジング外に取り出すための一対のリード線と、該芯線と該リード線とを接続する接続金具とを備えた温度センサの製造方法において、
前記芯線を固定する芯線固定部と、該芯線固定部と一体に形成され、前記リード線を固定するリード線固定部とを有し、該芯線固定部及び該リード線固定部の少なくとも一方が、該芯線又は該リード線である線材を自身の内側に配置しつつ、該線材を弾性的に保持可能に構成されている前記接続金具を用意する第１工程と、
該芯線固定部及び該リード線固定部の少なくとも一方に該線材が弾性的に保持されるように、前記接続金具に該線材を装着する第２工程と、
該線材を弾性的に保持する該芯線固定部及び該リード線固定部の少なくとも一方と、該線材とを溶接する第３工程とを備えたことを特徴とする。
【００１６】
本発明の温度センサの製造方法では、第１工程において接続金具を用意し、第２工程において接続金具に線材を弾性によって保持し、そして第３工程において接続金具に線材を溶接する。この温度センサの製造方法では、第２工程において線材を芯線固定部又はリード線固定部に保持させるに際して、芯線固定部又はリード線固定部を塑性変形させる必要がなく、線材を芯線固定部又はリード線固定部の所定位置に装着するだけで、線材が芯線固定部又はリード線固定部の所定の位置からずれることを防止することができる。そして、第３工程において溶接により確実に線材を芯線固定部又はリード線固定部に固定することができる。
【００１７】
したがって、本発明の温度センサの製造方法によれば、温度センサの品質を安定させ、信頼性が向上した温度センサを効率よく製造することができる。また、上述した特定の接続金具を用いることにより、ＭＩケーブルの芯線とリード線との接続が容易になり、温度センサの製造コストの低廉化を実現することができる。
【００１８】
また、温度センサ用接続金具は、軸方向に延びる連結部を有し、該連結部の先端側に前記芯線固定部が形成され、軸方向の後端側に前記リード線固定部が形成されていることが好ましい。これにより、連結部の両端より芯線及びリード線を芯線固定部及びリード線固定部に保持させることができ、作業性に優れる。
【００１９】
さらに、本発明の温度センサの製造方法では、接続金具の前記芯線固定部が前記芯線を自身の内側に配置しつつ、該芯線を弾性的に保持可能に構成されていることが好ましい。芯線は細い上、芯線間の距離が小さいため、芯線を芯線固定部内の所定位置に位置決めした上で位置ずれなくかしめ保持させるのは困難である。その点、芯線固定部が芯線を自身の内側に配置しつつ、この芯線を弾性的に保持可能に構成されていれば、芯線を芯線固定部に保持させた後、溶接により確実に芯線を芯線固定部に固定することができ、温度センサの品質を安定させ、信頼性を向上させる効果が大きい。
【００２０】
また、前記芯線固定部は、軸方向に延びる筒状に形成されて前記芯線を先端側から挿入させる筒部と、該筒部に形成されて該筒部の径方向の弾性を許容するスリットとをもつことが好ましい。これにより、芯線を筒部の先端側から挿入するだけで筒部の弾性力により芯線を保持可能とすることができる。
【００２１】
さらに、前記芯線固定部は、前記筒部の先端側に形成され、先端に向かって内径が拡径する呼込み部をもつことが好ましい。この呼込み部を有することにより、芯線を筒部の内側に容易に挿入することができる。
【００２２】
前記リード線固定部は前記リード線をかしめによって固定可能に構成されていることが好ましい。リード線は撚り線である場合が多く、溶接よりもかしめによって固定する方が適しているからである。
【００２３】
本発明の温度センサの製造方法では、前記第３工程をレーザ溶接によって行うことができる。レーザ溶接によれば芯線を芯線固定部に強固に固定することができる。
【００２４】
【発明の実施の形態】
以下、本発明の温度センサ用接続金具及び温度センサの製造方法を具体化した実施形態１、２を図面を参照しつつ説明する。
【００２５】
（実施形態１）
図１に実施形態１の温度センサ用接続金具及び温度センサの製造方法による温度センサの断面図を示す。この温度センサは、図示しない車両の排気通路に設けられ、排気ガスの温度を広範囲にわたって検出するために用いられる。
【００２６】
この温度センサは、ハウジング１と、ハウジング１内に収納され、温度により変化する電気的特性を電気信号として出力可能な感温素子としてのサーミスタ５と、サーミスタ５からの電気信号をハウジング１外に取り出すための一対のリード線６とを備えている。
【００２７】
より詳細には、ハウジング１は第１ハウジング２とフランジ３と第２ハウジング４とから構成されている。第１ハウジング２は先端が閉じられた円筒状をなし、その先端側には温度により変化する抵抗値を電気信号として一対の電極５ａに出力するサーミスタ５が配置されている。一対の電極５ａはＭＩケーブル１２の一対の芯線１１の一端１１ａに接続され、一対の芯線１１は第１ハウジング２の基端から突出している。なお、この第１ハウジング２は、フランジ３の内孔に圧入固定されている。
【００２８】
第２ハウジング４は第１ハウジング２より大径の円筒状をなしている。そして、第２ハウジング４の先端側と第１ハウジング２の基端側とが重ね合わせられて同軸に配置されている。
【００２９】
フランジ３は、軸線方向に延びる軸部３ｂと、この軸部３ｂの先端側に位置し、径方向外側に向かって突出する突出部３ａとを有している。突出部３ａは、先端側に図示しない排気管の取付部のテーパ部に対応したテーパ形状の座面３ｃをもつ環状に形成され、座面３ｃが上記取付部のテーパ部に密着することで排気ガスが排気管外部へ漏出することを防止する。また、軸部３ｂの外側には、第２ハウジング４の先端側が圧入され、さらに周方向にわたって軸部３ｂ、第２ハウジング４がレーザ溶接されている。なお、フランジ３の周囲には、雄ねじ１４ａ及び六角ナット部１４ｂを有するナット１４が回動可能に設けられている。
【００３０】
第１ハウジング２の基端から突出したＭＩケーブル１２における一対の芯線１１の他端１１ｂは、第２ハウジング４内において、接続金具１６の芯線固定部１６ｂにレーザ溶接によって固定されている。また、一対のリード線６の一端６ａは接続金具１６のリード線固定部１６ａにかしめによって固定されている。そして、芯線１１の他端１１ｂとリード線６の一端６ａとには、接続金具１６とともに絶縁チューブ１７が被せられている。
【００３１】
また、第２ハウジング４の基端側には、耐熱ゴム製のグロメット１８がかしめ固定されている。一対のリード線６はグロメット１８を貫通して、第２ハウジング４の基端より突出している。
【００３２】
次に、本実施形態の接続金具１６であって、芯線１１及びリード線６を未だ接続していないものを図２〜６に示す。図２は接続金具１６の上面図であり、図３は接続金具の正面図である。この接続金具１６は厚さ０．２ｍｍのＳＵＳ３０４製のものであり、接続金具１６には、軸方向に延びる連結部１６ｃの一端側（先端側）に芯線固定部１６ｂが形成されているとともに、他端側（後端側）にリード線固定部１６ａが形成されている。
【００３３】
リード線固定部１６ａの軸方向に垂直な断面（図２におけるＩＶ−ＩＶ断面）は、図４に示すように、リード線６をかしめによって固定可能なようにＵ字型をなしている。
【００３４】
芯線固定部１６ｂは、図２及び図３に示すように、芯線１１を先端側から挿入させる筒部１６ｄと、この筒部１６ｄの先端側に形成されるとともに、先端側に向かうほど内径が拡径する呼び込み部１６ｅとを有している。本実施形態の接続金具１６の筒部１６ｄは、周方向の一部に軸方向に延びるスリット１６ｆが一つ形成され、軸直交断面で見て、略真円形状の形態で形成された第１筒状部１６ｈと、この第１筒状部１６ｈの先端側に連結された第２筒状部１６ｊの二つの部位により構成されている。ここで、筒部１６ｄの第２筒状部１６ｊには、周方向の一部に軸方向に延びる二つのスリット１６ｆが向かい合うように形成されている。また、第２筒状部１６ｊは、先端が軸直交断面で見て略長円形状の形態をなし（図６参照）、後端が軸直交断面で見て略真円経常をなしており、先端から後端側（第１筒状部１６ｈに連結する側）に向かうほど略長円形状から略真円形状の形態になるように形成されている。なお、この第２筒状部１６ｊは、軸直交断面で見て、自身の中心軸線を通る最小寸法が先端から後端側に向かうほど大きくなるように形成されている。また、芯線固定部１６ｂのうち、筒部１６ｄの後端側は、芯線１１の進入を阻止するストッパ１６ｇをもっている。
【００３５】
図５に筒部１６ｄにおける第１筒状部１６ｈの略中央部の軸方向に垂直な断面（図２におけるＶ−Ｖ断面）を示す。また、図６に筒部１６Ｄにおける第２筒状部１６ｊの先端の軸方向に垂直な断面（図２におけるＶＩ−ＶＩ断面）を示す。ここで、芯線１１の外径は０．５ｍｍ、筒部１６ｄのうちで第１筒状部１６ｈの内径ｒ１は０．５ｍｍ、第２筒状部１６ｊの先端における軸直交断面で見て自身の中心軸線を通る最小寸法ｒ２は０．４ｍｍである。こうして、芯線１１を呼び込み部１６ｅから挿入させ、芯線１１の端部を筒部１６ｄのストッパ１６ｇに当たるまで挿入させることにより、筒部１６（第１筒状部１６ｈ及び第２筒状部１６ｊ）は弾性的に拡径しつつ、芯線１１を筒部１６ｄにて弾性的に保持可能に構成されている。つまり、芯線固定部１６ｄが芯線１１を弾性的に保持するのである。なお、第１筒状部１６ｈ、第２筒状部ｊに形成されるスリット１６ｆの数は、芯線１１の硬度等を考慮し、適正な弾性力が発揮されるように調整すればよい。
【００３６】
次に、本実施形態の温度センサの製造方法について説明する。まず、第１工程において、接続金具１６、第１ハウジング２にサーミスタ５及びＭＩケーブル１２が組み付けられたサブアッシー、リード線６、フランジ１３、ナット１４、第２ハウジング４、絶縁チューブ１７、グロメット１８等を用意する。
【００３７】
第２工程において、治具上に固定した接続金具１６の呼込み部１６ｅから、上記サブアッシーの芯線１１の先端がストッパ１６ｇに当接するまで挿入する。これにより、芯線１１が筒部１６ｄの弾性によって接続金具１６に保持される。
【００３８】
そして、第３工程において、芯線１１を弾性保持した状態の接続金具１６のうち、第２筒状部１６ｊの軸方向における略中央部に対してレーザを照射し、芯線１１を芯線固定部１６ｂに固定する。
【００３９】
最後に、リード線６をリード線固定部１６ａにかしめによって固定した後、フランジ１３、ナット１４、第２ハウジング４等を組み付けて温度センサが完成する。
【００４０】
以上の温度センサ用接続金具及び温度センサの製造方法では、芯線固定部１６ｂは芯線１１を弾性的に保持するように構成されている。そのため、芯線１１を芯線固定部１６ｂに保持させるに際して、芯線１１が芯線固定部１６ｂの所定の位置からずれることを防止することができる。そして、芯線１１を芯線固定部１６ｂに保持させた後、レーザ溶接により確実に芯線１１を芯線固定部１６ｂに固定することができる。そのため、芯線１１に引張力が加わっても、芯線１１に接続不良や断線が生じ難くなる。
【００４１】
また、この接続金具１６は、軸方向に延びる連結部１６ｃを有し、連結部１６ｃの一端側に芯線固定部１６ｂが形成され、軸方向の他端側にリード線固定部１６ａが形成されているため、連結部１６ｃの両端より芯線１１及びリード線６を芯線固定部１６ｂ及びリード線固定部１６ａに保持させることができ、作業性に優れる。さらに、この接続金具１６は、筒部１６ｄの先端側に先端に向かって自身の内径が拡径する呼込み部１６ｅが形成されているため、芯線１１を芯線固定部１６ｂに容易に挿入することができる。また、リード線６は撚り線であり、溶接よりもかしめによって固定する方が適していため、リード線固定部１６ａはリード線６をかしめによって固定可能に構成されている。
【００４２】
したがって、実施形態１の温度センサ用接続金具及び温度センサの製造方法によれば、温度センサの品質を安定させ、信頼性を向上させることができる。
【００４３】
また、この温度センサ用接続金具及び温度センサの製造方法によれば、芯線１１が芯線固定部１６ｂに確実に固定され、芯線１１と接続金具１６との接続部分に冷熱サイクルによる緩みが生じ難い。そのため、芯線１１と接続金具１６との接続部分を温度センサの先端部分からそれほど遠ざける必要がなく、温度センサの小型化を実現できる。
【００４４】
さらに、この温度センサ用接続金具及び温度センサの製造方法によれば、接続金具１６を介したＭＩケーブル１２の芯線１１とリード線６との接続に手間を要しないことから、温度センサの製造コストの低廉化も実現することができる。
【００４５】
（実施形態２）
実施形態２の温度センサの断面図は、実施形態１と同様、図１に示される。この温度センサの構成は実施形態１と同様であり、その説明を省略する。ただし、実施形態２では、接続金具１６の代わりに図７〜１０に示す接続金具２０を使用している。
【００４６】
芯線１１及びリード線６を未だ接続していない接続金具２０を図７〜１０に示す。図７は接続金具２０の上面図であり、図８は接続金具２０の正面図である。この接続金具２０は厚さ０．２ｍｍのＳＵＳ３０４製のものであり、接続金具２０には、軸方向に延びる連結部２０ｃの一端側に芯線固定部２０ｂが形成されるとともに、他端側にリード線固定部２０ａが形成されている。
【００４７】
リード線固定部２０ａの軸方向に垂直な断面（図７におけるＩＸ−ＩＸ断面）は、図９に示すように、リード線６をかしめによって固定可能なようにＵ字型をなしている。
【００４８】
芯線固定部２０ｂは、図７、８及び図１０に示すように、軸方向に延びる筒状に形成されるとともに、周方向の一部に軸方向に延びるスリット２０ｆが一つ形成された筒部２０ｄと、筒部２０ｄの先端側に形成され、先端に向かって自身の内径が拡径する呼込み部２０ｅとからなる。さらに、筒部２０ｄには、芯線１１を上方に押圧すべく、底面の一部が切欠きによって持ち上げられた舌片状の凸部２０ｇが形成されている。ここで、芯線１１の外径は０．５ｍｍであり、筒部２０ｄの軸方向に垂直な断面（図７におけるＸ−Ｘ断面）を表した図１０に示すように、筒部２０ｄの内径ｒ３は０．６ｍｍ、凸部２０ｇと筒部１６ｄとの最大長さｌ１が０．４ｍｍである。
【００４９】
次に、本実施形態の温度センサの製造方法について説明する。まず、第１工程において、接続金具２０、第１ハウジング２にサーミスタ５及びＭＩケーブル１２が組み付けられたサブアッシー、リード線６、フランジ１３、ナット１４、第２ハウジング４、絶縁チューブ１７、グロメット１８等を用意する。
【００５０】
第２工程において、治具上に固定した接続金具２０の呼込み部２０ｅから、上記サブアッシーの芯線１１を挿入する。これにより、筒部２０ｂ内において、芯線１１が筒部２０ｂの内周面と凸部２０ｇとの間に挟持され、ひいては芯線１１が弾性によって接続金具２０に保持される。
【００５１】
そして、第３工程において、芯線１１を弾性保持した状態の接続金具１６のうち、筒部２０ｄの軸方向における略中央部に対してレーザを照射し、芯線１１を芯線固定部２０ｂに固定する。
【００５２】
最後に、リード線６をリード線固定部２０ａにかしめによって固定した後、フランジ１３、ナット１４、第２ハウジング４等を組み付けて温度センサが完成する。
【００５３】
以上の温度センサ用接続金具及び温度センサの製造方法では、筒部２０ｄに舌片状の凸部２０ｇが形成されているため、これによって芯線１１の抜け落ちや移動を防止でき、より強く芯線１１を保持可能である。その他の作用、効果は実施形態１と同様である。
【図面の簡単な説明】
【図１】実施形態１の温度センサの断面図である。
【図２】実施形態１の温度センサに係り、接続金具の上面図である。
【図３】実施形態１の温度センサに係り、接続金具の正面図である。
【図４】実施形態１の温度センサに係り、接続金具のリード線固定部の断面図（図２におけるＩＶ−ＩＶ断面図）である。
【図５】実施形態１の温度センサに係り、接続金具の筒部の断面図（図２におけるＶ−Ｖ断面図）である。
【図６】実施形態１の温度センサに係り、接続金具の呼込み部の断面図（図２におけるＶＩ−ＶＩ断面図）である。
【図７】実施形態２の温度センサに係り、接続金具の上面図である。
【図８】実施形態２の温度センサに係り、接続金具の正面図である。
【図９】実施形態２の温度センサに係り、接続金具のリード線固定部の断面図（図７におけるＩＸ−ＩＸ断面図）である。
【図１０】実施形態２の温度センサに係り、接続金具の筒部の断面図（図７におけるＸ−Ｘ断面図）である。
【符号の説明】
１…ハウジング
１２…ＭＩケーブル
１１…芯線
５…感温素子（サーミスタ）
６…リード線
１６、２０…接続金具
１６ｃ、２０ｃ…連結部
１６ａ、２０ａ…リード線固定部
１６ｂ、２０ｂ…芯線固定部
１６ｄ、２０ｄ…筒部
１６ｆ、２０ｆ…スリット
１６ｅ、２０ｅ…呼込み部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a temperature sensor connection fitting and a method of manufacturing a temperature sensor. The temperature sensor according to the manufacturing method of the present invention is suitable for use when detecting the temperature of exhaust gas or the like of a vehicle.
[0002]
[Prior art]
Conventionally, a temperature sensor connecting metal fitting and a temperature sensor manufacturing method described in Patent Document 1 are known. The temperature sensor fitting and the temperature sensor according to the manufacturing method are housed in a housing, and a thermistor that outputs electrical characteristics that change depending on the temperature as an electrical signal to a pair of core wires of the MI cable, and an electrical signal from the thermistor. A pair of lead wires for taking out to the outside and a connection fitting for connecting the core wire and the lead wire are provided. The lead wire is fixed to the lead wire fixing portion of the connection fitting by caulking, and the core wire is fixed to the core wire fixing portion of the connection fitting by laser. The MI cable is also called a sheath core wire, and has a cylindrical metal pipe, a core wire disposed inside the metal pipe, and an insulating powder filled between the metal pipe and the core wire, and the core wire is made of metal. The pipe is insulated and held with insulating powder (see JIS F0031). This temperature sensor is attached to an exhaust passage of a vehicle as an object, for example. In this temperature sensor, the thermistor outputs a resistance value that varies depending on the temperature of the exhaust gas as an electrical signal to the pair of core wires of the MI cable, so that the electrical signal is sent out of the housing by the lead wire connected by the core wire and the connecting metal fitting. It will be taken out. Thus, the temperature of the exhaust gas is measured by this temperature sensor, and the engine of the vehicle is controlled according to the temperature.
[0003]
[Patent Document 1]
JP-A-2002-221451 [0004]
[Problems to be solved by the invention]
However, in the conventional temperature sensor connector and temperature sensor manufacturing method, the quality of the temperature sensor becomes unstable, and the reliability of the temperature sensor may be reduced.
[0005]
That is, conventionally, a connection fitting having a core wire fixing portion having an inner diameter larger than the outer diameter of the core wire of the MI cable is prepared, and the core wire is inserted into the core wire fixing portion in a loose-fitting manner, and a predetermined position in the core wire fixing portion is obtained. After positioning the core wire, the core wire fixing portion was caulked radially inward (plastically deformed), and then laser welding was performed to connect the core wire and the core wire fixing portion. However, in the configuration in which the core wire is held in the core wire fixing portion by plastically deforming the core wire fixing portion, the core wire is positioned at a predetermined position in the core wire fixing portion before the plastic deformation (caulking) is performed. Even so, the core wire may be displaced (lateral shift) with plastic deformation of the core wire fixing portion. When laser welding is performed in a state where the core wire is displaced from a predetermined position in the core wire fixing portion, the core wire has been displaced from a preset irradiation position of the laser beam. As a result, it is impossible to perform strong welding and the welding reliability is lowered. In this way, if the welding reliability between the core wire and the connection fitting (welding fixing part) is low, an excessive tensile force acts on the lead wire separately connected to the connection fitting, the connection state between the core wire and the welding fixing part However, it is easy to cause a failure, and an appropriate electric signal output cannot be obtained.
[0006]
The present invention has been made in view of the above-described conventional situation, and provides a temperature sensor connection fitting and a temperature sensor manufacturing method capable of stabilizing the quality of the temperature sensor and improving the reliability. This is a problem to be solved.
[0007]
[Means for Solving the Problems]
The temperature sensor connecting bracket of the present invention includes a core wire fixing portion for fixing the core wire of the MI cable, and a lead wire fixing portion that is formed integrally with the core wire fixing portion and fixes the lead wire, and constitutes a temperature sensor In the temperature sensor connection bracket
At least one of the core wire fixing portion and the lead wire fixing portion is configured to be able to elastically hold the wire while arranging the wire that is the core wire or the lead wire inside itself. To do.
[0008]
In the temperature sensor connecting bracket of the present invention, at least one of the core wire fixing portion and the lead wire fixing portion is configured to be able to elastically hold the wire while arranging the wire that is the core wire or the lead wire inside itself. Therefore, when holding the wire to the core wire fixing portion or the lead wire fixing portion, it is not necessary to plastically deform the core wire fixing portion or the lead wire fixing portion, and the wire is attached to a predetermined position of the core wire fixing portion or the lead wire fixing portion. As a result, it is possible to prevent the wire rod from shifting from a predetermined position of the core wire fixing portion or the lead wire fixing portion. And after holding a wire to a core wire fixing | fixed part or a lead wire fixing | fixed part, a wire can be reliably fixed to a core wire fixing | fixed part or a lead wire fixing | fixed part by welding etc.
[0009]
Therefore, the temperature sensor using the temperature sensor connecting bracket of the present invention can stabilize the quality and improve the reliability. In addition, by using the temperature sensor connection fitting of the present invention, it becomes easy to connect the core wire and the lead wire of the MI cable, and the manufacturing cost of the temperature sensor can be reduced.
[0010]
Further, the temperature sensor connecting bracket has a connecting portion extending in the axial direction, the core wire fixing portion is formed on the distal end side of the connecting portion, and the lead wire fixing portion is formed on the rear end side in the axial direction. Preferably it is. Thereby, the core wire and the lead wire can be held by the core wire fixing portion and the lead wire fixing portion from both ends of the connecting portion, and the workability is excellent.
[0011]
Furthermore, in the temperature sensor connection fitting according to the present invention, it is preferable that the core wire fixing portion is configured to be able to elastically hold the core wire while disposing the core wire inside itself. Since the core wires are thin and the distance between the core wires is small, it is difficult to caulk and hold the core wires without misalignment after being positioned at a predetermined position in the core wire fixing portion. In that respect, if the core wire fixing portion is arranged so that the core wire can be elastically held while the core wire is arranged inside itself, the core wire is securely held by the core wire after being held by the core wire fixing portion. It can be fixed to the fixing part, and the effect of stabilizing the quality of the temperature sensor and improving the reliability is great.
[0012]
Further, the core wire fixing portion is formed in a cylindrical shape extending in the axial direction and allows the core wire to be inserted from the distal end side, and a slit formed in the cylindrical portion to allow elasticity in the radial direction of the cylindrical portion. It is preferable to have As a result, the core wire can be held by the elastic force of the cylindrical portion simply by inserting the core wire from the distal end side of the cylindrical portion.
[0013]
Furthermore, it is preferable that the said core wire fixing | fixed part has a calling-in part which is formed in the front end side of the said cylinder part, and an internal diameter expands toward a front-end | tip. By having this lead-in portion, the core wire can be easily inserted inside the tube portion.
[0014]
It is preferable that the lead wire fixing portion is configured to fix the lead wire by caulking. This is because the lead wire is often a stranded wire and is more preferably fixed by caulking than by welding.
[0015]
A temperature sensor manufacturing method according to the present invention includes a housing, a temperature sensing element that is housed in the housing, and that outputs electrical characteristics that change according to temperature as an electrical signal to a pair of core wires of an MI cable, and the temperature sensing element. In a method for manufacturing a temperature sensor, comprising: a pair of lead wires for taking out the electrical signal from the housing; and a connection fitting for connecting the core wire and the lead wire.
A core wire fixing portion that fixes the core wire; and a lead wire fixing portion that is formed integrally with the core wire fixing portion and fixes the lead wire, and at least one of the core wire fixing portion and the lead wire fixing portion is: A first step of preparing the connection fitting configured to be able to elastically hold the wire, while arranging the wire that is the core wire or the lead wire inside;
A second step of attaching the wire to the connection fitting so that the wire is elastically held by at least one of the core wire fixing portion and the lead wire fixing portion;
A third step of welding at least one of the core wire fixing portion and the lead wire fixing portion that elastically holds the wire and the wire is provided.
[0016]
In the temperature sensor manufacturing method of the present invention, a connection fitting is prepared in the first step, the wire is elastically held in the connection fitting in the second step, and the wire is welded to the connection fitting in the third step. In this temperature sensor manufacturing method, when the wire is held in the core wire fixing portion or the lead wire fixing portion in the second step, it is not necessary to plastically deform the core wire fixing portion or the lead wire fixing portion, and the wire is fixed to the core wire fixing portion or the lead. It is possible to prevent the wire rod from being displaced from a predetermined position of the core wire fixing portion or the lead wire fixing portion only by being mounted at a predetermined position of the wire fixing portion. And in a 3rd process, a wire can be reliably fixed to a core wire fixing | fixed part or a lead wire fixing | fixed part by welding.
[0017]
Therefore, according to the method for manufacturing a temperature sensor of the present invention, it is possible to efficiently manufacture a temperature sensor having stabilized temperature sensor quality and improved reliability. Further, by using the above-described specific connection fitting, the connection between the core wire and the lead wire of the MI cable can be facilitated, and the manufacturing cost of the temperature sensor can be reduced.
[0018]
Further, the temperature sensor connecting bracket has a connecting portion extending in the axial direction, the core wire fixing portion is formed on the distal end side of the connecting portion, and the lead wire fixing portion is formed on the rear end side in the axial direction. Preferably it is. Thereby, the core wire and the lead wire can be held by the core wire fixing portion and the lead wire fixing portion from both ends of the connecting portion, and the workability is excellent.
[0019]
Furthermore, in the manufacturing method of the temperature sensor of this invention, it is preferable that the said core wire fixing | fixed part of a connection metal fitting is comprised so that it can hold | maintain this core wire elastically, arrange | positioning the said core wire inside itself. Since the core wires are thin and the distance between the core wires is small, it is difficult to caulk and hold the core wires without misalignment after being positioned at a predetermined position in the core wire fixing portion. In that respect, if the core wire fixing portion is arranged so that the core wire can be elastically held while the core wire is arranged inside itself, the core wire is securely held by the core wire after being held by the core wire fixing portion. It can be fixed to the fixing part, and the effect of stabilizing the quality of the temperature sensor and improving the reliability is great.
[0020]
Further, the core wire fixing portion is formed in a cylindrical shape extending in the axial direction and allows the core wire to be inserted from the distal end side, and a slit formed in the cylindrical portion to allow elasticity in the radial direction of the cylindrical portion. It is preferable to have As a result, the core wire can be held by the elastic force of the cylindrical portion simply by inserting the core wire from the distal end side of the cylindrical portion.
[0021]
Furthermore, it is preferable that the said core wire fixing | fixed part has a calling-in part which is formed in the front end side of the said cylinder part, and an internal diameter expands toward a front-end | tip. By having this lead-in portion, the core wire can be easily inserted inside the tube portion.
[0022]
It is preferable that the lead wire fixing portion is configured to fix the lead wire by caulking. This is because the lead wire is often a stranded wire and is more preferably fixed by caulking than by welding.
[0023]
In the temperature sensor manufacturing method of the present invention, the third step can be performed by laser welding. According to laser welding, the core wire can be firmly fixed to the core wire fixing portion.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, Embodiments 1 and 2 embodying the temperature sensor connection fitting and the temperature sensor manufacturing method of the present invention will be described with reference to the drawings.
[0025]
(Embodiment 1)
FIG. 1 shows a cross-sectional view of a temperature sensor according to a first embodiment of the temperature sensor connector and the method of manufacturing the temperature sensor. This temperature sensor is provided in an exhaust passage of a vehicle (not shown) and is used for detecting the temperature of exhaust gas over a wide range.
[0026]
This temperature sensor is housed in the housing 1, the thermistor 5 as a temperature sensing element capable of outputting an electrical characteristic that changes with temperature as an electrical signal, and the electrical signal from the thermistor 5 outside the housing 1. A pair of lead wires 6 for taking out is provided.
[0027]
More specifically, the housing 1 includes a first housing 2, a flange 3, and a second housing 4. The first housing 2 has a cylindrical shape with a closed tip, and a thermistor 5 that outputs a resistance value that varies with temperature as an electrical signal to the pair of electrodes 5a is disposed on the tip side. The pair of electrodes 5 a is connected to one end 11 a of the pair of core wires 11 of the MI cable 12, and the pair of core wires 11 protrudes from the base end of the first housing 2. The first housing 2 is press-fitted and fixed in the inner hole of the flange 3.
[0028]
The second housing 4 has a cylindrical shape with a larger diameter than the first housing 2. The distal end side of the second housing 4 and the proximal end side of the first housing 2 are overlapped and arranged coaxially.
[0029]
The flange 3 includes a shaft portion 3b extending in the axial direction, and a projecting portion 3a that is located on the distal end side of the shaft portion 3b and projects outward in the radial direction. The protruding portion 3a is formed in an annular shape having a tapered seat surface 3c corresponding to the tapered portion of the exhaust pipe mounting portion (not shown) on the tip side, and the seat surface 3c is in close contact with the tapered portion of the mounting portion to exhaust the exhaust. Prevents gas from leaking outside the exhaust pipe. Further, the distal end side of the second housing 4 is press-fitted outside the shaft portion 3b, and the shaft portion 3b and the second housing 4 are laser-welded over the circumferential direction. A nut 14 having a male screw 14a and a hexagon nut 14b is rotatably provided around the flange 3.
[0030]
The other end 11 b of the pair of core wires 11 in the MI cable 12 protruding from the base end of the first housing 2 is fixed to the core wire fixing portion 16 b of the connection fitting 16 by laser welding in the second housing 4. One end 6 a of the pair of lead wires 6 is fixed to the lead wire fixing portion 16 a of the connection fitting 16 by caulking. The other end 11 b of the core wire 11 and the one end 6 a of the lead wire 6 are covered with an insulating tube 17 together with the connection fitting 16.
[0031]
A grommet 18 made of heat-resistant rubber is caulked and fixed to the base end side of the second housing 4. The pair of lead wires 6 penetrates the grommet 18 and protrudes from the base end of the second housing 4.
[0032]
Next, the connection metal fitting 16 of this embodiment which has not yet connected the core wire 11 and the lead wire 6 is shown in FIGS. 2 is a top view of the connection fitting 16, and FIG. 3 is a front view of the connection fitting. This connection fitting 16 is made of SUS304 having a thickness of 0.2 mm. The connection fitting 16 has a core wire fixing portion 16b formed on one end side (tip end side) of a connecting portion 16c extending in the axial direction. A lead wire fixing portion 16a is formed on the other end side (rear end side).
[0033]
The cross section perpendicular to the axial direction of the lead wire fixing portion 16a (IV-IV cross section in FIG. 2) is U-shaped so that the lead wire 6 can be fixed by caulking, as shown in FIG.
[0034]
As shown in FIGS. 2 and 3, the core wire fixing portion 16b is formed at the distal end side of the cylindrical portion 16d for inserting the core wire 11 from the distal end side, and the inner diameter increases toward the distal end side. It has a calling-in part 16e to be diametered. The cylindrical portion 16d of the connection fitting 16 of the present embodiment has one slit 16f extending in the axial direction in a part of the circumferential direction, and is formed in a substantially perfect circle shape when viewed in the axial orthogonal cross section. The cylindrical portion 16h and the second cylindrical portion 16j connected to the distal end side of the first cylindrical portion 16h are constituted by two portions. Here, in the second cylindrical portion 16j of the cylindrical portion 16d, two slits 16f extending in the axial direction are formed in a part of the circumferential direction so as to face each other. Further, the second cylindrical portion 16j has a substantially oval shape when the tip is viewed in the axial orthogonal section (see FIG. 6), and the rear end is substantially circular when viewed in the axis orthogonal section. It forms so that it may become a form from a substantially oval shape to a substantially perfect circle shape, so that it goes to the rear end side (side connected with the 1st cylindrical part 16h) from the front-end | tip. Note that the second cylindrical portion 16j is formed such that the minimum dimension passing through the central axis of the second cylindrical portion 16j increases from the front end to the rear end side when viewed in the axial orthogonal cross section. In addition, the rear end side of the cylindrical portion 16 d of the core wire fixing portion 16 b has a stopper 16 g that prevents the core wire 11 from entering.
[0035]
FIG. 5 shows a cross section (VV cross section in FIG. 2) perpendicular to the axial direction of the substantially central portion of the first cylindrical portion 16h in the cylindrical portion 16d. FIG. 6 shows a cross section (VI-VI cross section in FIG. 2) perpendicular to the axial direction of the tip of the second cylindrical portion 16j in the cylindrical portion 16D. Here, the outer diameter of the core wire 11 is 0.5 mm, and the inner diameter r1 of the first cylindrical portion 16h out of the cylindrical portion 16d is 0.5 mm. The minimum dimension r2 passing through the central axis is 0.4 mm. Thus, by inserting the core wire 11 from the calling portion 16e and inserting the end of the core wire 11 until it contacts the stopper 16g of the cylindrical portion 16d, the cylindrical portion 16 (the first cylindrical portion 16h and the second cylindrical portion 16j) is The core wire 11 is configured to be elastically held by the cylindrical portion 16d while being elastically expanded. That is, the core wire fixing portion 16d elastically holds the core wire 11. In addition, what is necessary is just to adjust the number of the slits 16f formed in the 1st cylindrical part 16h and the 2nd cylindrical part j, considering the hardness etc. of the core wire 11, so that an appropriate elastic force may be exhibited.
[0036]
Next, the manufacturing method of the temperature sensor of this embodiment is demonstrated. First, in the first step, the connection fitting 16, the subassembly in which the thermistor 5 and the MI cable 12 are assembled to the first housing 2, the lead wire 6, the flange 13, the nut 14, the second housing 4, the insulating tube 17, and the grommet 18. Prepare etc.
[0037]
In the second step, the insertion is performed from the insertion portion 16e of the connection fitting 16 fixed on the jig until the tip of the core wire 11 of the sub-assembly comes into contact with the stopper 16g. Thereby, the core wire 11 is hold | maintained at the connection metal fitting 16 with the elasticity of the cylinder part 16d.
[0038]
And in a 3rd process, among the connection metal fittings 16 in the state where the core wire 11 is elastically held, a laser is irradiated to a substantially central portion in the axial direction of the second cylindrical portion 16j, and the core wire 11 is applied to the core wire fixing portion 16b. Fix it.
[0039]
Finally, after fixing the lead wire 6 to the lead wire fixing portion 16a by caulking, the temperature sensor is completed by assembling the flange 13, the nut 14, the second housing 4, and the like.
[0040]
In the temperature sensor connecting bracket and the temperature sensor manufacturing method described above, the core wire fixing portion 16b is configured to elastically hold the core wire 11. Therefore, when the core wire 11 is held by the core wire fixing portion 16b, the core wire 11 can be prevented from shifting from a predetermined position of the core wire fixing portion 16b. And after holding the core wire 11 in the core wire fixing | fixed part 16b, the core wire 11 can be reliably fixed to the core wire fixing | fixed part 16b by laser welding. For this reason, even if a tensile force is applied to the core wire 11, connection failure or disconnection hardly occurs in the core wire 11.
[0041]
The connection fitting 16 has a connecting portion 16c extending in the axial direction, a core wire fixing portion 16b is formed on one end side of the connecting portion 16c, and a lead wire fixing portion 16a is formed on the other end side in the axial direction. Therefore, the core wire 11 and the lead wire 6 can be held by the core wire fixing portion 16b and the lead wire fixing portion 16a from both ends of the connecting portion 16c, and the workability is excellent. Furthermore, since the connection fitting 16 is formed with a calling portion 16e whose inner diameter increases toward the distal end of the cylindrical portion 16d, the core wire 11 can be easily inserted into the core wire fixing portion 16b. it can. Moreover, since the lead wire 6 is a stranded wire and is more preferably fixed by caulking than by welding, the lead wire fixing portion 16a is configured to be able to fix the lead wire 6 by caulking.
[0042]
Therefore, according to the temperature sensor connecting metal fitting and the temperature sensor manufacturing method of Embodiment 1, the quality of the temperature sensor can be stabilized and the reliability can be improved.
[0043]
Further, according to the temperature sensor connection fitting and the temperature sensor manufacturing method, the core wire 11 is securely fixed to the core wire fixing portion 16b, and the connection portion between the core wire 11 and the connection fitting 16 is unlikely to be loosened due to the cooling and heating cycle. Therefore, it is not necessary to keep the connecting portion between the core wire 11 and the connection fitting 16 far from the tip portion of the temperature sensor, and the temperature sensor can be downsized.
[0044]
Further, according to the temperature sensor connecting metal fitting and the temperature sensor manufacturing method, it is not necessary to connect the core wire 11 of the MI cable 12 and the lead wire 6 via the connecting metal fitting 16, so that the temperature sensor manufacturing cost is reduced. Can also be realized.
[0045]
(Embodiment 2)
A cross-sectional view of the temperature sensor of the second embodiment is shown in FIG. The structure of this temperature sensor is the same as that of Embodiment 1, and the description thereof is omitted. However, in the second embodiment, the connection fitting 20 shown in FIGS. 7 to 10 is used instead of the connection fitting 16.
[0046]
7 to 10 show the connection fitting 20 to which the core wire 11 and the lead wire 6 are not yet connected. FIG. 7 is a top view of the connection fitting 20, and FIG. 8 is a front view of the connection fitting 20. The connection fitting 20 is made of SUS304 having a thickness of 0.2 mm. The connection fitting 20 is formed with a core wire fixing portion 20b on one end side of a connecting portion 20c extending in the axial direction and a lead on the other end side. A line fixing portion 20a is formed.
[0047]
The cross section (IX-IX cross section in FIG. 7) perpendicular to the axial direction of the lead wire fixing portion 20a is U-shaped so that the lead wire 6 can be fixed by caulking, as shown in FIG.
[0048]
As shown in FIGS. 7, 8 and 10, the core wire fixing portion 20b is formed in a cylindrical shape extending in the axial direction, and a cylindrical portion in which one slit 20f extending in the axial direction is formed in a part of the circumferential direction. 20d and a call-in part 20e which is formed on the tip side of the cylindrical part 20d and whose inner diameter increases toward the tip. Furthermore, a tongue-like convex portion 20g having a part of the bottom surface lifted by a notch is formed on the cylindrical portion 20d so as to press the core wire 11 upward. Here, the outer diameter of the core wire 11 is 0.5 mm, and as shown in FIG. 10 showing a cross section (XX cross section in FIG. 7) perpendicular to the axial direction of the cylindrical portion 20d, the inner diameter r3 of the cylindrical portion 20d. Is 0.6 mm, and the maximum length l1 between the convex portion 20g and the cylindrical portion 16d is 0.4 mm.
[0049]
Next, the manufacturing method of the temperature sensor of this embodiment is demonstrated. First, in the first step, the connection fitting 20, the subassembly in which the thermistor 5 and the MI cable 12 are assembled to the first housing 2, the lead wire 6, the flange 13, the nut 14, the second housing 4, the insulating tube 17, and the grommet 18. Prepare etc.
[0050]
In the second step, the core wire 11 of the sub-assembly is inserted from the incoming portion 20e of the connection fitting 20 fixed on the jig. Thereby, in the cylinder part 20b, the core wire 11 is clamped between the internal peripheral surface of the cylinder part 20b, and the convex part 20g, and the core wire 11 is hold | maintained at the connection metal fitting 20 by elasticity by extension.
[0051]
And in a 3rd process, a laser is irradiated with respect to the substantially metal | metal center part in the axial direction of the cylinder part 20d among the connection metal fittings 16 of the state which hold | maintained the core wire 11 elastically, and the core wire 11 is fixed to the core wire fixing | fixed part 20b.
[0052]
Finally, after the lead wire 6 is fixed to the lead wire fixing portion 20a by caulking, the temperature sensor is completed by assembling the flange 13, the nut 14, the second housing 4, and the like.
[0053]
In the above-described temperature sensor connector and temperature sensor manufacturing method, since the tongue-like convex portion 20g is formed on the cylindrical portion 20d, it is possible to prevent the core wire 11 from falling off and moving, and the core wire 11 is more strongly attached. It can be held. Other actions and effects are the same as those of the first embodiment.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a temperature sensor according to a first embodiment.
FIG. 2 is a top view of a connection fitting according to the temperature sensor of the first embodiment.
FIG. 3 is a front view of a connection fitting according to the temperature sensor of the first embodiment.
4 is a cross-sectional view (IV-IV cross-sectional view in FIG. 2) of a lead wire fixing portion of a connection fitting according to the temperature sensor of Embodiment 1. FIG.
FIG. 5 is a cross-sectional view (cross-sectional view taken along line VV in FIG. 2) of a cylindrical portion of a connection fitting according to the temperature sensor of the first embodiment.
6 is a cross-sectional view (cross-sectional view taken along the line VI-VI in FIG. 2) of the fitting portion of the connection fitting according to the temperature sensor of Embodiment 1. FIG.
7 is a top view of a connection fitting according to the temperature sensor of Embodiment 2. FIG.
FIG. 8 is a front view of a connection fitting according to the temperature sensor of the second embodiment.
FIG. 9 is a cross-sectional view of the lead wire fixing portion of the connection fitting (IX-IX cross-sectional view in FIG. 7) according to the temperature sensor of the second embodiment.
10 is a cross-sectional view (XX cross-sectional view in FIG. 7) of the cylindrical portion of the connection fitting according to the temperature sensor of Embodiment 2. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Housing 12 ... MI cable 11 ... Core wire 5 ... Temperature sensing element (thermistor)
6 ... Lead wires 16, 20 ... Connection fittings 16c, 20c ... Connecting portions 16a, 20a ... Lead wire fixing portions 16b, 20b ... Core wire fixing portions 16d, 20d ... Tube portions 16f, 20f ... Slits 16e, 20e ... Inlet portions

Claims

In a temperature sensor connecting bracket for forming a temperature sensor, comprising: a core wire fixing portion that fixes a core wire of an MI cable; and a lead wire fixing portion that is integrally formed with the core wire fixing portion and fixes a lead wire.
At least one of the core wire fixing portion and the lead wire fixing portion is configured to be able to elastically hold the wire while arranging the wire that is the core wire or the lead wire inside itself. Connecting bracket for temperature sensor.

2. A connecting portion extending in an axial direction, wherein the core wire fixing portion is formed on a distal end side of the connecting portion, and the lead wire fixing portion is formed on a rear end side in the axial direction. The temperature sensor connection bracket described.

The temperature sensor connecting bracket according to claim 1 or 2, wherein the core wire fixing portion is configured to elastically hold the core wire while the core wire is disposed inside the core wire fixing portion.

The core wire fixing portion includes a cylindrical portion that is formed in a cylindrical shape extending in the axial direction and into which the core wire is inserted from the distal end side, and a slit that is formed in the cylindrical portion and allows elasticity in the radial direction of the cylindrical portion. The temperature sensor connecting bracket according to claim 3.

5. The temperature sensor connecting bracket according to claim 4, wherein the core wire fixing portion has a calling portion that is formed on a distal end side of the cylindrical portion and whose inner diameter increases toward the distal end.

The temperature sensor connecting bracket according to any one of claims 3 to 5, wherein the lead wire fixing portion is configured to be able to fix the lead wire by caulking.

A housing, a temperature sensing element that is housed in the housing, and outputs an electrical characteristic that changes depending on temperature as a pair of core wires of the MI cable, and the electrical signal from the temperature sensing element is taken out of the housing. In a method for manufacturing a temperature sensor, comprising a pair of lead wires for connecting, and a connection fitting for connecting the core wire and the lead wire,
A core wire fixing portion that fixes the core wire; and a lead wire fixing portion that is formed integrally with the core wire fixing portion and fixes the lead wire, and at least one of the core wire fixing portion and the lead wire fixing portion is: A first step of preparing the connection fitting configured to be able to elastically hold the wire, while arranging the wire that is the core wire or the lead wire inside;
A second step of attaching the wire to the connection fitting so that the wire is elastically held by at least one of the core wire fixing portion and the lead wire fixing portion;
A temperature sensor manufacturing method comprising: a third step of welding at least one of the core wire fixing portion and the lead wire fixing portion that elastically holds the wire, and the wire.

The connection fitting has a connecting portion extending in the axial direction, the core wire fixing portion is formed on the distal end side of the connecting portion, and the lead wire fixing portion is formed on the rear end side in the axial direction. The manufacturing method of the temperature sensor of Claim 7.

9. The method of manufacturing a temperature sensor according to claim 7, wherein the core wire fixing portion is configured to be able to elastically hold the core wire while arranging the core wire inside thereof.

The core wire fixing portion includes a cylindrical portion that is formed in a cylindrical shape extending in the axial direction and into which the core wire is inserted from the distal end side, and a slit that is formed in the cylindrical portion and allows elasticity in the radial direction of the cylindrical portion. The method of manufacturing a temperature sensor according to claim 9.

The method of manufacturing a temperature sensor according to claim 10, wherein the core wire fixing portion has a calling portion that is formed on a distal end side of the cylindrical portion and whose inner diameter increases toward the distal end.

The temperature sensor manufacturing method according to claim 7, wherein the lead wire fixing portion is configured to be capable of fixing the lead wire by caulking.

The temperature sensor manufacturing method according to claim 7, wherein the third step is performed by laser welding.