【０００１】
【発明の属する技術分野】
この発明は、半導体の洗浄装置、産業機械、農業、食品、医療関係などの各分野における水質管理、原子力発電所の冷却水の絶縁性及び各種の薬液の濃度管理などに用いられる抵抗率計の電極に関する。
【０００２】
【従来の技術】
半導体の洗浄装置、産業機械、農業、食品、医療関係などの各分野における水質管理、原子力発電所の冷却水の絶縁性及び各種の薬液の濃度管理などにおいて、超純水の純度や電解質液の濃度を測定するために、前記超純水や電解質液の抵抗率を測定する抵抗率計が用いられる。
【０００３】
例えば、半導体の製造工程では、被洗浄物としての半導体ウェーハを洗浄槽内に挿入してアンモニアなどの洗浄液で洗浄する（洗浄工程）。そして、前記アンモニアを排出するとともに超純水（不純物を意図的に極めて少なくした水：超高純度水ともいう）を洗浄槽内に入れて、前記半導体ウェーハを濯いでいる（リンス工程）。前記リンス工程において、アンモニアと入れ替えられた超純水の純度を測定する際には、例えば、図１２に示す電極１０１を備えた抵抗率計が用いられる。
【０００４】
図１２に例示された抵抗率計の電極１０１は、内電極１０２と、外電極１０３と、前記内電極１０２及び外電極１０３を支持する支持部１０４と、を備えている。内電極１０２は、導電性の金属からなる。内電極１０２は、一端部（以下先端部と呼ぶ）１０２ｂが塞がれた円管状に形成されている。内電極１０２は、大径部１０５と、小径部１０６と、を一体に備えている。小径部１０６の外径は、大径部１０５の外径より小さい。大径部１０５と小径部１０６とは、互いに同軸的でかつ互いに直列に配されている。
【０００５】
外電極１０３は、導電性の金属からなる。外電極１０３は、円管状に形成されている。外電極１０３の内径は、内電極１０２の外径より大きい。外電極１０３内に内電極１０２が挿入されて、これらの内外電極１０２，１０３は、互いに同軸的に配されている。支持部１０４は、内電極１０２の小径部１０６の基端部１０２ａと、外電極１０３の基端部１０３ａとを支持している。
【０００６】
前述した構成によって、抵抗率計の電極１０１は、前記内電極１０２及び外電極１０３それぞれの少なくとも先端部１０２ｂ，１０３ｂを、計測対象の電解質液の流路中に配置し、これらの電極１０２，１０３間の電気抵抗を測定することより前記電解質液の抵抗率を測定する。そして、測定した抵抗率に基いて、超純水などの電解質液の純度を求める。
【０００７】
【発明が解決しようとする課題】
前述した抵抗率計の電極１０１の電極部材としての内電極１０２は、導電性の金属からなり、かつ互いに外径の異なる大径部１０５と小径部１０６とを一体に備えている。このため、前記内電極１０２は、例えば、前記金属からなる円柱状の部材に切削加工などを施して製造されてきた。このため、前記部材の無駄になる部分が非常に多い（材料歩留まりが非常に悪化する）。
【０００８】
又、前記大径部１０５と小径部１０６とに亘って穴１０７をあける必要があって、非常に製造しずらかった。このため、製造にかかる所要工数が増加する傾向であった。したがって、抵抗率計の電極１０１のコストが高騰する傾向であった。
【０００９】
したがって、本発明の目的は、コストの高騰を抑制できる抵抗率計の電極を提供することにある。
【００１０】
【課題を解決するための手段】
前記課題を解決し目的を達成するために、請求項１に記載の本発明の抵抗率計の電極は、計測対象の電解質液の流路中に複数の電極部材が所定間隔をあけて配置され、前記電極部材間の電気抵抗に基いて前記電解質液の抵抗率を測定する抵抗率計の電極において、前記複数の電極部材のうち少なくとも一つの電極部材は、円管状に形成された互いに外径の異なる大径部材と小径部材とを有し、かつこれらの大径部材と小径部材とが互いに同軸的に連結し、前記小径部材の外周面に第１のねじ山が形成され、前記大径部材の内周面に前記第１のねじ山が螺合する第２のねじ山が形成され、前記第１のねじ山と前記第２のねじ山とが螺合すると、前記大径部材と小径部材のいずれか一方に形成されているとともに、他方に圧入する圧入部を備えていることを特徴としている。
【００１２】
請求項２に記載の本発明の抵抗率計の電極は、請求項１記載の抵抗率計の電極において、前記大径部材と前記小径部材とは、互いに連結すると互いに相対する面をそれぞれ備えており、前記圧入部は、前記大径部材の面と前記小径部材の面とのうち一方から他方に向かって突出した突起であり、前記第１のねじ山と前記第２のねじ山とが螺合すると、該突起が他方にくい込むことを特徴としている。
【００１３】
請求項３に記載の本発明の抵抗率計の電極は、請求項１記載の抵抗率計の電極において、前記圧入部は、前記小径部材に設けられかつ第１のねじ山より大径部材寄りに設けられ、かつ外径が前記大径部材の内径より大きく形成されていることを特徴としている。
【００１４】
請求項４に記載の本発明の抵抗率計の電極は、請求項１記載の抵抗率計の電極において、前記圧入部は、前記大径部材に設けられかつ第２のねじ山より小径部材寄りに設けられ、かつ内径が前記小径部材の外径より小さく形成されていることを特徴としている。
【００１５】
請求項５に記載の本発明の抵抗率計の電極は、計測対象の電解質液の流路中に複数の電極部材が所定間隔をあけて配置され、前記電極部材間の電気抵抗に基いて前記電解質液の抵抗率を測定する抵抗率計の電極において、前記複数の電極部材のうち少なくとも一つの電極部材は、円管状に形成された互いに外径の異なる大径部材と小径部材とを有し、かつこれらの大径部材と小径部材とが互いに同軸的に連結し、前記大径部材の内側に前記小径部材の一端部が挿入されて、前記大径部材と小径部材とが連結するとともに、前記大径部材の内周面と小径部材の外周面とのうち一方に凹部が形成され、他方に凸部が形成されており、前記大径部材の内側に前記小径部材の一端部が挿入されると、前記凹部内に前記凸部が係合することを特徴としている。
【００１６】
請求項６に記載の本発明の抵抗率計の電極は、請求項１ないし請求項５のうちいずれか一項に記載の抵抗率計の電極において、前記電極部材として円管状の内電極と円管状の外電極とを備え、前記外電極の内側に前記内電極が挿入されて、これらの内外電極が互いに同軸的に配されているとともに、前記内電極が前記大径部材と前記小径部材とを有していることを特徴としている。
【００１７】
請求項７に記載の本発明の抵抗率計の電極は、請求項１ないし請求項５のうちいずれか一項に記載の抵抗率計の電極において、前記電極部材として円管状の内電極と円管状の外電極とを備え、前記外電極の内側に前記内電極が挿入されて、これらの内外電極が互いに同軸的に配されているとともに、前記外電極が前記大径部材と前記小径部材とを有していることを特徴としている。
【００１８】
請求項８に記載の本発明の抵抗率計の電極は、請求項１ないし請求項５のうちいずれか一項に記載の抵抗率計の電極において、前記電極部材として円管状の内電極と円管状の外電極とを備え、前記外電極の内側に前記内電極が挿入されて、これらの内外電極が互いに同軸的に配されているとともに、前記内電極と外電極との双方が前記大径部材と前記小径部材とを有していることを特徴としている。
【００１９】
請求項１に記載した本発明の抵抗率計の電極によれば、少なくとも一つの電極部材が、大径部材と小径部材とを備えている。これらの大径部材と小径部材とが連結している。このため、大径部材と小径部材とを別々に製造して、これらを連結して、前記電極部材を製造できる。
【００２０】
第１のねじ山と第２のねじ山とを螺合させると、大径部材と小径部材のいずれか一方の圧入部が他方に圧入する。このため、大径部材と小径部材とに接着剤を塗布して、これらの部材を互いに固定する際にも、大径部材の母材と小径部材の母材とが確実に接触する。
【００２１】
請求項２に記載した本発明の抵抗率計の電極によれば、圧入部が他方に食い込むので、大径部材と小径部材とに接着剤を塗布して、これらの部材を互いに固定する際にも、大径部材の母材と小径部材の母材とが確実に接触する。
【００２２】
請求項３に記載した本発明の抵抗率計の電極によれば、第１のねじ山より大径部材寄りの圧入部の外径が大径部材の内径より大きい。このため、大径部材と小径部材とに接着剤を塗布することなく、これらの部材を互いに固定できる。
【００２３】
請求項４に記載した本発明の抵抗率計の電極によれば、第２のねじ山より小径部材寄りに配された圧入部の内径が小径部材の外径より小さい。このため、大径部材と小径部材とに接着剤を塗布することなく、これらの部材を互いに固定できる。
【００２４】
請求項５に記載した本発明の抵抗率計の電極によれば、大径部材の内周面と小径部材の外周面のうち一方から凹の凹部に、他方から凸部が係合する。このため、大径部材と小径部材とに接着剤を塗布することなく、これらの部材を互いに固定できる。
【００２５】
請求項６に記載した本発明の抵抗率計の電極によれば、内電極が大径部材と小径部材とを備えている。このため、大径部材と小径部材とを別々に製造して、これらを連結して、前記内電極を製造できる。
【００２６】
請求項７に記載した本発明の抵抗率計の電極によれば、外電極が大径部材と小径部材とを備えている。このため、大径部材と小径部材とを別々に製造して、これらを連結して、前記外電極を製造できる。
【００２７】
請求項８に記載した本発明の抵抗率計の電極によれば、内外電極が大径部材と小径部材とを備えている。このため、大径部材と小径部材とを別々に製造して、これらを連結して、前記内外電極それぞれを製造できる。
【００２８】
【発明の実施の形態】
本発明の一実施形態にかかる抵抗率計の電極１を、図１ないし図７を参照して説明する。図１などに示す抵抗率計の電極１は、半導体の洗浄装置、産業機械、農業、食品、医療関係などの各分野における超純水などの水質管理、原子力発電所の冷却水の絶縁性及び電解質液としての各種の薬液の濃度管理などに用いられる。
【００２９】
電極１は、例えば、半導体ウェーハなどの被洗浄物などを洗浄する半導体の製造工程におけるリンス工程において、洗浄液としての超純水（特許請求の範囲等に記載した電解質液に相当する）の純度を測定するために用いられる。前記電極１を用いる抵抗率計は、計測対象物としての前述した超純水などの電解質液の純度を測定するために、前記電解質液の抵抗率を測定する装置である。
【００３０】
前記電極１は、前記超純水などの流路中に配されかつ図１に示すように前記流路を構成するＴ字管継手６０に取り付けられる。Ｔ字管継手６０は、図１に示すように、前記流路を構成する管部６１ａ，６１ｂ，６１ｃを備えている。
【００３１】
一つの管部６１ａには、半導体ウェーハを収容しかつ前記洗浄工程及びリンス工程などを行う洗浄槽などが連結している。他の一つの管部６１ｂには、前述した洗浄工程及びリンス工程などに用いられた処理液などを排出する排出管が連結している。他の一つの管部６１ｃに、電極１が取り付けられる。前記管部６１ｃの外周面には、ねじ山としてのテーパねじ６２等が形成されている。
【００３２】
抵抗率計の電極１は、図１に示すように、電極部材としての内電極２と、電極部材としての外電極３と、シール部材８と、前記内電極２及び外電極３を支持する支持部４と、温度検出部５と、前記内電極２と電気的に接続した電線としての内電極リード線６と、前記外電極３と電気的に接続した電線としての外電極リード線７と、取付手段としての袋ナット７１と、付勢手段としてのコイルばね７２と、シール突起３３と、を備えている。
【００３３】
内電極２は、導電性を有する金属などから構成されている。内電極２は、一端部（以下先端部と呼ぶ）２ｇが塞がれた円管状に形成されている。内電極２は、図２及び図３などに示すように、外径が比較的小さい小径部材２ａと、外径が比較的大きい大径部材２ｂと、を備えている。これらの小径部材２ａと大径部材２ｂとは、互いに同軸的でかつ直列に連結している。
【００３４】
大径部材２ｂは、例えば、チタン（Titanium）などの高強度でかつ耐食性の金属からなる。大径部材２ｂは、先端部２ｇが塞がれた円管状に形成されており、外径が全長に亘って略一定に形成されている。小径部材２ａは、例えば、ステンレス鋼などの金属からなる。小径部材２ａは、円管状に形成されている。小径部材２ａは、外径が全長に亘って略一定に形成されている。小径部材２ａは、外表面から凹に形成された凹溝２ｈを備えている。凹溝２ｈは、小径部材２ａの周方向に沿って形成されている。
【００３５】
大径部材２ｂと小径部材２ａとは、図３に示すように、第１のねじ山４１と第２のねじ山４２と圧入部としての突起４３（図４に示す）によって、互いに直列に連結される。第１のねじ山４１は、小径部材２ａの一端部（以下先端部と呼ぶ）４４の外周面に形成されている。このため、小径部材２ａは、所謂雄ねじとなっている。
【００３６】
第２のねじ山４２は、大径部材２ｂの他端部（以下基端部と呼ぶ）４５の内周面に形成されている。このため、大径部材２ｂは、所謂雌ねじとなっている。第２のねじ山４２には、第１のねじ山４１がねじ込まれる。即ち、第１のねじ山４１と第２のねじ山４２とは、互いに螺合する。
【００３７】
小径部材２ａと大径部材２ｂとは、第１のねじ山４１と第２のねじ山４２とが互いに螺合すると、互いに相対するとともに互いに重なる面４６，４７を備えている。これらの面４６，４７は、円環状でかつ小径部材２ａと大径部材２ｂの軸芯即ち内電極２の軸芯に対し直交する方向に沿って平坦である。
【００３８】
突起４３は、小径部材２ａの面４６と大径部材２ｂの面４７とのうち一方から他方に向かって突出している。図示例では、突起４３は、図４に示すように、小径部材２ａの面４６から大径部材２ｂの面４７に向かって凸に形成されている。突起４３は、円環状である。突起４３の断面形状は、先が尖った山形に形成されている。
【００３９】
内電極２は、第１のねじ山４１と第２のねじ山４２とが互いに螺合して、小径部材２ａと大径部材２ｂとが直列に連結されて得られる。これらの第１のねじ山４１と第２のねじ山４２とが螺合する際には、これらのねじ山４１，４２に接着剤が塗布される。さらに、ねじ山４１，４２が互いに螺合すると、尖っているため、図４に示すように、突起４３が大径部材２ｂの母材にくい込む。
【００４０】
前述した構成の内電極２を組み立てる際には、まず、第１のねじ山４１と第２のねじ山４２に接着剤を塗布する。図５（ａ）に示すように、第１のねじ山４１を第２のねじ山４２に徐々にねじ込んで、大径部材２ｂ内に小径部材２ａの先端部４４から徐々に挿入する。
【００４１】
すると、図５（ｂ）に示すように、突起４３が、大径部材２ｂの面４７に接触する。さらに、第１のねじ山４１を第２のねじ山４２にねじ込むと、図５（ｃ）に示すように、突起４３が大径部材２ｂの母材に徐々にくい込む。そして、図４に示すように、面４６，４７が互いに相対するとともに重なって、小径部材２ａと大径部材２ｂとが固定されて、前述した構成の内電極２を得る。
【００４２】
内電極２は、前記大径部材２ｂが抵抗率計の電極１の先端側に位置しかつ小径部材２ａが基端側に位置した状態で配される。前記内電極２の小径部材２ａと大径部材２ｂの内側は、温度検出部挿入孔２ｄをなしている。
【００４３】
前記温度検出部挿入孔２ｄは、前記小径部材２ａ及び大径部材２ｂそれぞれと互いに同軸的に配されている。温度検出部挿入孔２ｄは、内電極２の基端部２ｆ側の端面２ｃと前記内電極２の先端部２ｇとに亘って形成されている。なお、温度検出部挿入孔２ｄは、勿論、基端部２ｆ側の端面２ｃには開口しているが、内電極２の先端部２ｇ側の端面２ｅには開口していない。
【００４４】
外電極３は、導電性を有する金属などから構成されている。外電極３は、円管状に形成されている。外電極３は、図２及び図３などに示すように、内外径が比較的小さい小径部材３ｄと、内外径が比較的大きい大径部材３ｅと、を備えている。
【００４５】
大径部材３ｅは、全長に亘って内外径が略一定に形成されている。大径部材３ｅの内径は、内電極２の大径部材２ｂの外径より大きい。大径部材３ｅは、基端部５５に前述した電解質液を通す通し孔４８を複数設けている。通し孔４８は、大径部材３ｅを貫通している。また、大径部材３ｅの内径が、前記基端部５５から先端部３ｃに向かうにしたがって段階的に大きくなる段差４９が形成されている。段差４９は、通し孔４８の先端部３ｃ寄りに設けられている。
【００４６】
小径部材３ｄは、図２及び図３に示すように、円管状の円管部５０ａと、円環状の円環部５０ｂと、を一体に備えている。円管部５０ａは、全長に亘って内外径が略一定に形成されている。円管部５０ａの内径は、内電極２の小径部材２ａの外径より大きい。
【００４７】
円環部５０ｂは、円管部５０ａの一端部（以下先端部と呼ぶ）に連なっている。円環部５０ｂは、円管部５０ａと同軸的である。このため、円環部５０ｂは、円管部５０ａの全周に亘って、円管部５０ａの先端部から該円管部５０ａの外周方向に突出している。円環部５０ｂの外径は、大径部材３ｅの内径と略等しい。また、円環部５０ｂには、外周面から更に外周方向に突出したフランジ部５０ｃが一体に形成されている。又、円環部５０ｂは、本明細書に記した小径部材３ｄの一端部をなしている。
【００４８】
これらの小径部材３ｄと大径部材３ｅとは、図３に示すように、第１のねじ山５１と第２のねじ山５２と圧入部としての突起５３（図６に示す）によって、互いに同軸的でかつ直列に連結している。なお、第１のねじ山５１と第２のねじ山５２とが後述するように螺合すると、前記小径部材３ｄと大径部材３ｅとを互いに連ねる円環部５０ｂは、後述するように内外電極２，３が互いに同軸に配された際に内電極２の段差部２ｉと平行になる。
【００４９】
第１のねじ山５１は、小径部材３ｄの円環部５０ｂの外周面に形成されている。このため、小径部材３ｄは、所謂雄ねじとなっている。第２のねじ山５２は、大径部材３ｅの基端部５５の内周面に形成されている。このため、大径部材３ｅは、所謂雌ねじとなっている。第２のねじ山５２には、第１のねじ山５１がねじ込まれる。即ち、第１のねじ山５１と第２のねじ山５２とは、互いに螺合する。
【００５０】
小径部材３ｄと大径部材３ｅとは、第１のねじ山５１と第２のねじ山５２とが互いに螺合すると、互いに相対するとともに互いに重なる面５６，５７を備えている。これらの面５６，５７は、円環状でかつ小径部材２ａと大径部材２ｂの軸芯即ち内電極２の軸芯に対し直交する方向に沿って平坦である。
【００５１】
小径部材３ｄの面５６は、フランジ部５０ｃの表面である。大径部材３ｅの面５７は、該大径部材３ｅの基端部５５側の端面である。突起５３は、小径部材３ｄの面５６と大径部材３ｅの面５７とのうち一方から他方に向かって突出している。図示例では、突起５３は、図６に示すように、大径部材３ｅの面５７から小径部材３ｄの面５６に向かって凸に形成されている。突起５３は、円環状である。突起５３の断面形状は、先が尖った山形に形成されている。
【００５２】
外電極３は、第１のねじ山５１と第２のねじ山５２とが互いに螺合して、小径部材３ｄと大径部材３ｅとが直列に連結されて得られる。これらの第１のねじ山５１と第２のねじ山５２とが螺合する際には、これらのねじ山５１，５２に接着剤が塗布される。さらに、ねじ山５１，５２が互いに螺合すると、尖っているため、図６に示すように、突起５３が小径部材３ｄの母材にくい込む。
【００５３】
前述した構成の外電極３を組み立てる際には、まず、大径部材３ｅを構成する内外径一定の円管状の部材の周壁に通し孔４８をあける。その後、内周面に切削加工などを施して、前記段差４９を形成する。その後、第２のねじ山５２を大径部材３ｅの内周面に形成するとともに、小径部材３ｄの円環部５０ｂの外周面に第１のねじ山５１を形成する。
【００５４】
第１のねじ山５１と第２のねじ山５２に接着剤を塗布する。図７（ａ）に示すように、第１のねじ山５１を第２のねじ山５２に徐々にねじ込んで、大径部材３ｅ内に小径部材３ｄを徐々に挿入する。
【００５５】
すると、図７（ｂ）に示すように、突起５３が、小径部材３ｄの面５６に接触する。さらに、第１のねじ山５１を第２のねじ山５２にねじ込むと、図７（ｃ）に示すように、突起５３が小径部材３ｄの母材に徐々にくい込む。そして、図６に示すように、面５６，５７が互いに相対するとともに重なって、小径部材３ｄと大径部材３ｅとが固定されて、前述した構成の外電極３を得る。
【００５６】
内電極２と外電極３とは、図３に示すように、小径部材２ａが小径部材３ｄ内に配され大径部材２ｂが大径部材３ｅ内に配された格好で配される。即ち、内電極２と外電極３とは、外電極３の内側に内電極２が挿入されて、互いに同軸的に配されている。内電極２は、前記大径部材２ｂの端面２ｅが、前記外電極３の先端部３ｃ側に位置する端面３ａより若干外電極３の奥側に位置した状態で配されている。
【００５７】
シール部材８は、プラストマ性を有する即ちエラストマ性を有さない合成樹脂からなる。即ち、シール部材８は、殆ど弾性変形しない。シール部材８は、可塑性の大きい高分子物質からなる。本実施形態では、シール部材８は、前述した電解質液に対する溶出する物質が少ない非溶出性のフッ素樹脂などからなる。即ち、シール部材８は、非溶出性である。
【００５８】
シール部材８は、図１ないし図３に示すように、円板部８ａと筒部８ｂとを一体に備えている。円板部８ａは、平面形状が円形でかつ厚みが略一定の円板状に形成されている、円板部８ａの両表面は、平坦に形成されている。円板部８ａは、外径が外電極３の大径部材３ｅの内径と略等しく形成されている。
【００５９】
円板部８ａは、中央に孔８ｃを設けている。孔８ｃは、円板部８ａを貫通している。孔８ｃは、平面形状が円形に形成されている。孔８ｃは、内径が内電極２の小径部材２ａの外径と略等しく形成されている。
【００６０】
筒部８ｂは、孔８ｃの縁に連なっている。筒部８ｂは円筒状に形成されている。筒部８ｂは、円板部８ａに対し立設している。筒部８ｂは、内径が内電極２の小径部材２ａの外径と略等しく形成されている。筒部８ｂは、外径が外電極３の小径部材３ｄの円管部５０ａの内径と略等しく形成されている。筒部８ｂは、小径部材２ａの外周と小径部材３ｄの内周との双方に嵌合して、電極２，３間の間隔を所定間隔ｔに保つ。
【００６１】
前述した構成のシール部材８は、支持部４が電極２，３それぞれの基端部２ｆ，３ｂを支持する際に、図１及び図２に示すように、円板部８ａが段差部２ｉと円環部５０ｂとの間に配され筒部８ｂが小径部材２ａ，３ｄ相互間に配される。
【００６２】
このとき、シール部材８は殆ど弾性変形しなくかつ円板部８ａの両表面が平坦に形成されているので、前記両表面が段差部２ｉと円環部５０ｂとの双方に隙間無く接するとともに、筒部８ｂが小径部材２ａ，３ｄ双方に隙間無く接する。シール部材８は、内外電極２，３間を液密に保ち、内外電極２，３間から後述する空間１６内に電解質液が侵入することを防止する。
【００６３】
前記支持部４は、内電極２の小径部材２ａ寄りの端部２ｆ（基端部と呼ぶ）と、外電極３の前記小径部材３ｄ寄りの端部３ｂ（基端部と呼ぶ）と、の双方を支持している。支持部４は、支持部本体としての外電極ホルダ１１と、基端キャップ１２などを備えている。
【００６４】
外電極ホルダ１１は、絶縁性を有しかつ前述した電解質液に対する溶出する物質が少ない即ち非溶出性の合成樹脂からなる。外電極ホルダ１１を構成する合成樹脂として、ポリフェニレンスルフィド（Polyphenylenesulfide：以下ＰＰＳと呼ぶ）、ポリエーテルエーテルケトン（Polyetheretherketone：以下ＰＥＥＫと呼ぶ）、ポリテトラフルオロエチレン（Polytetrafluoroethylene：以下ＰＴＦＥと呼ぶ）などのフッ素樹脂を用いることができる。
【００６５】
外電極ホルダ１１は、円板部１１ｃと筒部１１ｄとを備えた有底筒状に形成されている。円板部１１ｃは、平面形状が円形に形成されている。円板部１１ｃは、表面が略平坦に形成されている。円板部１１ｃの外径は、前記管部６１ｃの端面６１ｄの外径と略等しく形成されている。
【００６６】
円板部１１ｃの中央には孔１１ｅが設けられている。孔１１ｅは円板部１１ｃを貫通している。孔１１ｅは、平面形状が円形に形成されている。孔１１ｅの内径は、円板部１１ｃの一方の面から他方の面に向かうにしたがって略等しく形成されている。孔１１ｅは、内径が外電極３の小径部材３ｄの円管部５０ａの外径と略等しく形成されている。
【００６７】
筒部１１ｄは、それぞれ円筒状に形成されかつ互いに内径が等しく形成されているとともに同軸的に直列に配された小径部１１ａと大径部１１ｂとを備えている。小径部１１ａより大径部１１ｂの方が外径が大きく形成されている。大径部１１ｂは、小径部１１ａより円板部１１ｃ寄りに配されている。大径部１１ｂは、円板部１１ｃの外縁に連なっている。筒部１１ｄは、円板部１１ｃに対し立設している。
【００６８】
外電極ホルダ１１は、孔１１ｅ内に外電極３の小径部材３ｄを挿入した状態で配される。なお、このとき、小径部材３ｄの円管部５０ａの外径が長手方向に沿って略一定でかつ孔１１ｅの内径が略一定であり、かつ外電極ホルダ１１が前述した合成樹脂からなるので、孔１１ｅの内面と小径部材３ｄの外表面とが互いに隙間無く密接する。
【００６９】
このため、外電極ホルダ１１即ち支持部４と外電極３との間が液密に保たれ、前記空間１６内に外電極ホルダ１１と外電極３との間から前記電解質液が侵入することが防止される。また、凹溝２ｈが円板部１１ｃより基端部２ｆ側に位置しているとともに、空間１６内に配されている。
【００７０】
基端キャップ１２は、円板部１２ａと筒部１２ｂとを有する有底筒状に形成されている。円板部１２ａは、円板状に形成されている。筒部１２ｂは、筒状に形成されかつ円板部１２ａの周縁に連なっている。
【００７１】
基端キャップ１２は、周知のポリアミド樹脂（ナイロン）などの合成樹脂から形成されている。基端キャップ１２は、前記筒部１２ｂが前記外電極ホルダ１１の小径部１１ａの外周に嵌合して配されている。基端キャップ１２は、前記筒部１２ｂが前記小径部１１ａに、周知のエポキシ系接着剤によって接着されて固定されている。
【００７２】
基端キャップ１２は、前記円板部１２ａを貫通する丸孔１２ｃを備えている。丸孔１２ｃは、その平面形状が略円形に形成されている。丸孔１２ｃは、前記円板部１２ａと同軸に配されている。丸孔１２ｃは、その内側に、温度検出部５の後述する電線束２６が通る。
【００７３】
また、支持部４は、外電極ホルダ１１の円板部１１ｃと、筒部１１ｄと、基端キャップ１２の円板部１２ａ等で囲まれた空間１６を、その内部に形成している。
【００７４】
支持部４は、さらに、前記空間１６内に配された絶縁ワッシャ２０と、止め輪１９と、円板部２１と円管部２２とが一体に形成された導電ホルダー２７と、第２付勢手段としてのコイルばね９などを備えている。
【００７５】
絶縁ワッシャ２０は、絶縁性を有する合成樹脂からなりかつ円環状に形成されている。絶縁ワッシャ２０は、内径が小径部材２ａの外径と略等しく形成され、かつ、外径が導電ホルダー２７の内径と略等しいか若干小さく形成されている。絶縁ワッシャ２０は、小径部材２ａの外周に嵌合している。絶縁ワッシャ２０は小径部材３ｄの端と、凹溝２ｈと、の間に配されている。
【００７６】
止め輪１９は、ステンレス鋼などの導電性を有する周知の鋼などからなりかつ円環状に形成されている。止め輪１９は、その内側に内電極２の小径部材２ａが通った状態で、外電極ホルダ１１の筒部１１ｄ内に収容されている。
【００７７】
止め輪１９は、その内縁が、小径部材２ａの凹溝２ｈに嵌合している。止め輪１９は、絶縁ワッシャ２０の端面２ｃ寄りの表面に密接している。止め輪１９は、内縁が凹溝２ｈに嵌合することによって絶縁ワッシャ２０が小径部材２ａの基端部２ｆから抜け出ることを防止している。
【００７８】
導電ホルダー２７の円板部２１は、導電性を有する金属などからなり円板状に形成されている。導電ホルダー２７の円板部２１は、内径が外電極３の小径部材３ｄの外径と略等しく形成されている。導電ホルダー２７の円板部２１は、外径が筒部１１ｄの内径と略等しく形成されている。導電ホルダー２７の円板部２１は、小径部材３ｄの外周に嵌合しかつ外電極ホルダ１１の内周に嵌合した状態で、円板部１１ｃに重ねられている。
【００７９】
導電ホルダー２７の円管部２２は、導電性を有する金属などからなり円管状に形成されている。導電ホルダー２７の円管部２２は、内径が小径部材３ｄの外径より十分に大きく形成されている。導電ホルダー２７の円管部２２は、外径が筒部１１ｄの内径と略等しく形成されている。導電ホルダー２７の円管部２２は、端部が導電ホルダー２７の円板部２１に一体形成され筒部１１ｄ内に挿入されている。
【００８０】
コイルばね９は、比較的ばね定数が小さくされている。コイルばね９は、ステンレス鋼などの周知の鋼などから構成されている。コイルばね９は、導電ホルダー２７の円管部２２内でかつ絶縁ワッシャ２０と導電ホルダー２７の円板部２１との間に設けられている。コイルばね９は、その内側に内外電極２，３の小径部材２ａ，３ｄが通った状態で配されている。
【００８１】
コイルばね９は、互いに離れる方向に、絶縁ワッシャ２０と導電ホルダー２７の円板部２１とを互いに付勢している。コイルばね９が、絶縁ワッシャ２０と導電ホルダー２７の円板部２１とが互いに離れる方向に付勢し、かつ、絶縁ワッシャ２０が止め輪１９によって基端部２ｆから抜け出ることを防止されているため、内電極２の基端部２ｆが支持部４内に収容するように付勢される。
【００８２】
円板部１１ｃと円環部５０ｂと円板部８ａと段差部２ｉとが相互に近づくように、内外電極２，３とシール部材８と外電極ホルダ１１とが付勢される。このように、コイルばね９は、内電極２の基端部２ｆと支持部４との間の間隔が狭くなる方向に、内電極２と支持部４とを付勢している。
【００８３】
また、前記コイルばね９によって互いの間隔が狭くなるように、内電極２と支持部４との双方が付勢されているため、シール部材８の両表面が段差部２ｉと円環部５０ｂとの双方に確実に隙間無く密接する。即ち、シール部材８は、内外電極２，３に隙間無く密接する。そして、シール部材８は、内外電極２，３相互間を液密に保って、空間１６内に前述した超純水が侵入することを防止する。
【００８４】
さらに、前記コイルばね９によって互いの間隔が狭くなるように、内電極２と支持部４との双方が付勢されているため、円板部１１ｃと円環部５０ｂとが確実に隙間無く密接する。そして、円板部１１ｃと円環部５０ｂとの相互間が液密に保たれて、空間１６内に前述した超純水が侵入することが防止される。
【００８５】
また、前記空間１６には、前記温度検出部挿入孔２ｄが開口している。さらに、空間１６は、その内側に、導電リング２３と、導電線２４と、前記導電ホルダー２７の円管部２２の内周面に嵌合するなどして取り付けられるリング１７などを収容している。
【００８６】
導電リング２３は、導電性を有する金属などからなりかつ円管状に形成されている。導電リング２３は、内径が小径部材３ｄの外径と略等しく形成されている。導電リング２３は、外径が円管部２２の内径より十分に小さく形成されている。導電リング２３は、小径部材３ｄの基端部３ｂ寄りの端部の外周に嵌合している。
【００８７】
導電線２４は、一端が導電リング２３に半田などを用いたろう付けによって固定され、他端が導電ホルダー２７の円板部２１とコイルばね９との間に挟み込まれて（又は線を直接又は別部品のワッシャーに半田などを用いたろう付けするなどして）固定されている。導電線２４は、導電リング２３と、導電ホルダー２７とを互いに電気的に接続する。
【００８８】
リング１７は、図示例では、円環状のリング本体１７ａと、このリング本体１７ａの外縁から外周方向に向かって突出した爪１７ｂと、を備えている。爪１７ｂは複数設けられている。爪１７ｂは、リング本体１７ａの周方向に沿って略等間隔に配されている。
【００８９】
リング１７は、爪１７ｂが、導電ホルダー２７の円管部２２の内周面に嵌合して、導電ホルダー２７の円管部２２に固定される。リング１７は、ステンレス鋼などの周知の鋼などから構成されている。さらに、リング１７は、爪１７ｂが導電ホルダー２７の円管部２２の内周面に設けられた溝などに嵌合しても良い。
【００９０】
前記温度検出部５は、図示しない温度センサ素子と、円管ばね部材２５などを備えている。温度検出部５は、前記温度検出部挿入孔２ｄ内に配されている。温度センサ素子は、温度検出部挿入孔２ｄ内でかつ内電極２の先端部２ｇに配されている。温度センサ素子は、温度を測定する感温部を備えている。
【００９１】
温度センサ素子は、感温部がディスク形、ペレット形あるいはそれに類似した面部を有する形状のサーミスタ及び薄膜式白金温度センサにより構成されている。温度センサ素子は、感温部の面部が、前記温度検出部挿入孔２ｄ内において、前記電解質液の流路に対し略平行となるように配置されている。温度センサ素子には図示しない電線が取り付けられている。
【００９２】
前記電線は、前記内電極２の先端部２ｇから内電極２の基端部２ｆに向かって延びて、温度検出部挿入孔２ｄ内に配されている。これらの電線は、それぞれ、図示しない演算装置などに電気的に接続している。
【００９３】
これら図示しない電線の長手方向に沿った中央部から他端部に至る部分と、内電極リード線６と、外電極リード線７と、は互いに束ねられて電線束２６を構成している。電線束２６は、温度検出部５が温度検出部挿入孔２ｄ内に収容された際に、内電極２及び外電極３の基端部２ｆ，３ｂ側に位置する基端キャップ１２の丸孔１２ｃを通って外部に導かれる。
【００９４】
円管ばね部材２５は、導電性を有する周知の鋼などから構成されている。円管ばね部材２５は、円管状に形成されている。円管ばね部材２５は、一部が、長手方向に沿って切りかかれている。円管ばね部材２５は、その長手方向に対し交差する断面の断面形状がＣ状に形成されている。円管ばね部材２５は、その外径が伸縮自在となる弾性を有している。円管ばね部材２５は、初期状態において、内電極２の小径部材２ａの内径より大きな外径となっている。
【００９５】
円管ばね部材２５は、前記電線束２６の温度センサ素子寄りに配されている。円管ばね部材２５は、前述した図示しない前記電線を互いに束ねている。円管ばね部材２５は、その弾性復元力に抗して、小径部材２ａ内に挿入される。円管ばね部材２５は、小径部材２ａ内に挿入されると、弾性復元力を生じて、小径部材２ａの内周面と密接する。
【００９６】
内電極リード線６は、空間１６内に収容されかつ一端部が円管ばね部材２５と電気的に接続している。内電極リード線６は、円管ばね部材２５と電気的に接続することによって、内電極２と電気的に接続する。内電極リード線６は、前述した図示しない電線などとともに電線束２６として基端キャップ１２まで導かれ、丸孔１２ｃ内を通って外部に導かれる。内電極リード線６は、前述した図示しない演算装置などに電気的に接続している。
【００９７】
外電極リード線７は、空間１６内に収容されかつ一端部がリング１７に電気的に接続している。外電極リード線７は、リング１７に電気的に接続することによって、導電ホルダー２７の円管部２２及び円板部２１、導電リング２３及び外電極３と電気的に接続する。外電極リード線７は、前述した図示しない電線などとともに電線束２６として基端キャップ１２まで導かれ、前記丸孔１２ｃ内を通って外部に導かれる。外電極リード線７は、前述した図示しない演算装置などに電気的に接続している。
【００９８】
また、前記基端キャップ１２内には、シリコーンゴムなどの弾性体からなるＯリング３０が設けられている。Ｏリング３０は、円環状に形成されている。Ｏリング３０は、その初期状態において、内径が電線束２６の外径より小さくかつ外径が外電極ホルダ１１の小径部１１ａの内径より大きく形成されている。
【００９９】
Ｏリング３０は、内側に電線束２６を通しかつ外電極ホルダ１１の小径部１１ａの内側即ち基端キャップ１２の筒部１２ｂの内側に配される。Ｏリング３０は、基端キャップ１２内に設けられると、電線束２６と、外電極ホルダ１１の小径部１１ａの内周面と、の間を液密に保つ。
【０１００】
Ｏリング３０は、例えは、電解質液の温度が比較的低くて、基端キャップ１２の丸孔１２ｃの近傍などに凝縮した結露水が付着する場合にも、空間１６内にこの結露水が侵入することを防止する。
【０１０１】
また、前記温度検出部挿入孔２ｄ内に温度検出部５が設けられ、かつ前記空間１６内にリング１７及び止め輪１９などが収容された状態で、空間１６内には、非弾性層３１と弾性層３２とが充填されて積層されている。
【０１０２】
非弾性層３１は、小径部１１ａ内でかつ電線束２６の外周に充填されている。非弾性層３１は、内外電極２，３の長手方向に沿ってＯリング３０とリング１７との間に配されている。非弾性層３１は、弾性を有さないエポキシ樹脂などの非弾性体からなる合成樹脂から形成されている。
【０１０３】
弾性層３２は、電極２，３の長手方向に沿って、非弾性層３１とリング１７との間に充填されている。弾性層３２は、スポンジゴムなどの弾性体からなる合成樹脂から形成されている。これらの非弾性層３１と弾性層３２は、丸孔１２ｃの近傍などに付着した結露水が空間１６内に侵入することを防止する。
【０１０４】
袋ナット７１は、前述したＰＰＳ、ＰＥＥＫ、ＰＴＦＥなどのフッ素樹脂などの合成樹脂からなり、平面形状が円形の円板部７３と円筒状の筒部７４とを一体に備えている。円板部７３は、その外径が外電極ホルダ１１及び管部６１ｃの外径より大きく形成されている。
【０１０５】
円板部７３は、その中央に貫通孔７５が設けられている。貫通孔７５は、その内径が外電極ホルダ１１の小径部１１ａの外径と略等しく形成されている。筒部７４は、円板部７３の外縁に連なっている。筒部７４の内周面には、平行ねじ７６が形成されている。
【０１０６】
袋ナット７１は、貫通孔７５内に小径部１１ａ即ち支持部４を通した状態で、平行ねじ７６がテーパねじ６２にねじ込まれて管部６１ｃに取り付けられる。なお、このとき、筒部７４の円板部７３より離れた縁部が、管部６１ｃの軸線方向に沿ってテーパねじ６２の中央付近に位置する。また、袋ナット７１は、外電極ホルダ１１即ち支持部４と管部６１ｃとの双方の外周を包囲する。 袋ナット７１は、管部６１ｃに取り付けられることによって、外電極ホルダ１１即ち支持部４を管部６１ｃの端面６１ｄに向かって押しつける。
【０１０７】
コイルばね７２は、比較的ばね定数が小さい。コイルばね７２は、ステンレス鋼などの周知の鋼などから構成され、断面形状が矩形状に形成されている。袋ナット７１の平行ねじ７６が管部６１ｃのテーパねじ６２にねじ込まれた際に、コイルばね７２は、その内側に小径部１１ａを通しかつ小径部１１ａと大径部１１ｂとを連ねる段差面１１ｆと円板部７３との間に配される。
【０１０８】
コイルばね７２は、外電極ホルダ１１即ち支持部４を管部６１ｃの端面６１ｄに向かって付勢する。コイルばね７２は、シール突起３３を管部６１ｃの端面６１ｄに密接させる。
【０１０９】
シール突起３３は、外電極ホルダ１１の管部６１ｃの端面６１ｄに相対する円板部１１ｃの表面１１ｇから突出している。なお、前記表面１１ｇは、Ｔ字継手６０の管部６１ｃと近接する端面をなしている。シール突起３３は、管部６１ｃの端面６１ｄに向かって突出している。シール突起３３は、孔１１ｅ及び円板部１１ｃと同軸的な円環状に延在している。
【０１１０】
シール突起３３は、円板部１１ｃの周方向に沿って配されている。シール突起３３は、外電極ホルダ１１と同じＰＰＳ、ＰＥＥＫ、ＰＴＦＥなどのフッ素樹脂などの合成樹脂からなる。図示例では、シール突起３３は、外電極ホルダ１１と一体に形成されかつ断面形状が前記円板部１１ｃから離れるのにしたがって徐々に細くなるＵ字状に形成されている。
【０１１１】
前述した構成によれば、抵抗率計の電極１は、内外電極２，３が前記管部６１ｃの開口部を通して挿入され、テーパねじ６２に平行ねじ７６がねじ込まれて、前記管部６１ｃ即ちＴ字管継手６０に取り付けられる。前記内電極２及び外電極３それぞれの少なくとも先端部２ｇ，３ｃは、前記Ｔ字管継手６０内を流れる電解質液としての超純水の流路中に配される。
【０１１２】
そして、電極１を用いた抵抗率計は、前記リード線６，７などを介して演算装置などに伝えられる電極２，３間の電気抵抗を測定することにより前記電解質液の抵抗率を測定する。
【０１１３】
このとき、前記温度センサ素子の感温部から、前記電線などを介して前記電解質液の温度に応じた情報が、前記演算装置に伝えられる。そして、この演算装置などが電解質液の温度の補償を行い、この電解質液のあらかじめ決められた一定温度における抵抗率を算出する。そして、前記演算装置などが抵抗率に基いて電解質液の純度を算出する。
【０１１４】
本実施形態の抵抗率計の電極１によれば、内電極２と外電極３が、大径部材２ｂ，３ｅと小径部材２ａ，３ｄとを備えている。大径部材２ｂ，３ｅと小径部材２ａ，３ｄとが連結している。このため、大径部材２ｂ，３ｅと小径部材２ａ，３ｄとを別々に製造して、これらを連結して、前記内電極２と外電極３とを製造できる。
【０１１５】
また、大径部材２ｂ，３ｅと小径部材２ａ，３ｄとを別々に製造できるので、特に、大径部材２ｂに形成する穴の深さを浅くできる。更に、内電極２の小径部材２ａと外電極３の大径部材３ｅを円管状の部材から形成できる。大径部材３ｅに通し孔４８をあけた後、該大径部材３ｅの内面に切削加工を施す。このため、通し孔４８の縁に生じるバリを確実に除去でき、かつ該バリを除去するためにかかる所要工数を抑制できる。
【０１１６】
したがって、大径部材２ｂ，３ｅと小径部材２ａ，３ｄとを別々に製造できるので、内外電極２，３の材料歩留まりの悪化と、加工にかかる所用時間を抑制できる。したがって、内外電極２，３のコストの高騰を抑制して、抵抗率計の電極１のコストの高騰を抑制できる。内電極２の小径部材２ａがステンレス鋼からなる。このため、材料費を抑制できる。したがって、コストの高騰をより確実に抑制できる。
【０１１７】
また、第１のねじ山４１，５１と第２のねじ山４２，５２とを螺合させると、大径部材２ｂ，３ｅと小径部材２ａ，３ｄのいずれか一方の突起４３，５３が他方に圧入される。該突起４３，５３が他方の母材にくい込む。このため、第１のねじ山４１，５１と第２のねじ山４２，５２とに接着剤を塗布して、大径部材２ｂ，３ｅと小径部材２ａ，３ｄを互いに固定する際にも、前記大径部材２ｂ，３ｅの母材と小径部材２ａ，３ｄの母材とが確実に接触する。したがって、大径部材２ｂ，３ｅと小径部材２ａ，３ｄとが確実に電気的に接続する。したがって、電解質液の抵抗率を確実に測定できる。
【０１１８】
前述した実施形態では、内電極２の小径部材２ａに突起４３を設け、外電極３の大径部材３ｅに突起５３を設けている。しかしながら本発明では、内電極２の大径部材２ｂに突起４３を設け、外電極３の小径部材３ｄに突起５３を設けても良い。また、内電極２と外電極３との双方とも、小径部材２ａ，３ｄと大径部材２ｂ，３ｅを連結して構成している。しかしながら本発明では、内外電極２，３のうち少なくとも一方を、小径部材２ａ，３ｄと大径部材２ｂ，３ｅを連結して構成すれば良い。
【０１１９】
前記内電極２の大径部材２ｂと小径部材２ａとを、図８に示すように、第１のねじ山４１と第２のねじ山４２と圧入部としての小径部材２ａの先端部４４とを用いて連結しても良い。第１のねじ山４１は、小径部材２ａの外周面に形成されている。第１のねじ山４１は、小径部材２ａの中央部に設けられている。
【０１２０】
第２のねじ山４２は、大径部材２ｂの内周面に形成されている。第１のねじ山４１と第２のねじ山４２とは互いに螺合する。先端部４４は、勿論小径部材２ａに設けられ、第１のねじ山４１より大径部材２ｂ寄りに配されている。先端部４４の外径Ｄ１は、大径部材２ｂの内径ｄ１より若干大きい。先端部４４の外径Ｄ１と大径部材２ｂの内径ｄ１との差は、０．０１ｍｍ以上でかつ０．０５ｍｍ以下の範囲であるのが望ましい。
【０１２１】
この場合、大径部材２ｂと小径部材２ａとを連結する際に、第１のねじ山４１と第２のねじ山４２とを螺合させる。すると、前記先端部４４の外径Ｄ１が大径部材２ｂの内径ｄ１より若干大きいので、該先端部４４が大径部材２ｂ内に圧入される。そして、内電極２が組み立てられる。
【０１２２】
前述した実施形態と同様に、大径部材２ｂと小径部材２ａとを別々に製造できるので、内電極２の材料歩留まりの悪化と、加工にかかる所用時間を抑制できる。したがって、内電極２のコストの高騰を抑制して、抵抗率計の電極１のコストの高騰を抑制できる。また、先端部４４の外径Ｄ１が大径部材２ｂの内径ｄ１より若干大きい。このため、第１のねじ山４１と第２のねじ山４２とに接着剤を塗布することなく、大径部材２ｂと小径部材２ａとを固定できる。したがって、接着剤を用いる必要がないので、大径部材２ｂと小径部材２ａとを確実に電気的に接続でき、電解質液の抵抗率を確実に測定できる。
【０１２３】
また、内電極２の大径部材２ｂと小径部材２ａとを、図９に示すように、凸部５８ａと、該凸部５８ａが係合する凹部５９ａとを用いて連結しても良い。凸部５８ａは、小径部材２ａの先端部４４の外周面から凸に形成されている。凹部５９ａは、大径部材２ｂの内周面から凹に形成されている。
【０１２４】
また、この場合、小径部材２ａの先端部４４の外径Ｄ１は、大径部材２ｂの内径ｄ１より若干大きいのが望ましい。小径部材２ａの先端部４４の外径Ｄ１と大径部材２ｂの内径ｄ１との差は、０．０１ｍｍ以上でかつ０．０３ｍｍ以下の範囲であるのが望ましい。また、前記凸部５８ａの外周面からの突出量と、凹部５９ａの内周面からの深さは、前記寸法の半分の０．００５ｍｍ〜０．０１５ｍｍ程度であるのが望ましい。
【０１２５】
この場合、大径部材２ｂと小径部材２ａとを連結する際に、大径部材２ｂの内側に小径部材２ａの先端部４４を挿入する。すると、前記先端部４４の外径Ｄ１が大径部材２ｂの内径ｄ１より若干大きいので、該先端部４４が大径部材２ｂ内に圧入される。そして、凸部５８ａが凹部５９ａに係合して、内電極２が組み立てられる。
【０１２６】
前述した実施形態と同様に、大径部材２ｂと小径部材２ａとを別々に製造できるので、内電極２の材料歩留まりの悪化と、加工にかかる所用時間を抑制できる。したがって、内電極２のコストの高騰を抑制して、抵抗率計の電極１のコストの高騰を抑制できる。また、先端部４４の外径Ｄ１が大径部材２ｂの内径ｄ１より若干大きくかつ凸部５８ａと凹部５９ａとが互いに係合する。このため、接着剤を塗布することなく、大径部材２ｂと小径部材２ａとを固定できる。したがって、接着剤を用いる必要がないので、大径部材２ｂと小径部材２ａとを確実に電気的に接続でき、電解質液の抵抗率を確実に測定できる。
【０１２７】
また、図９に示すように、凸部５８ａと凹部５９ａとを用いて大径部材２ｂと小径部材２ａとを固定する場合には、凸部５８ａを大径部材２ｂの内周面から凸に形成し、凹部５９ａを小径部材２ａの外周面から凹に形成しても良い。
【０１２８】
前記外電極３の大径部材３ｅと小径部材３ｄとを、図１０に示すように、第１のねじ山５１と第２のねじ山５２と圧入部としての大径部材３ｅの基端部５５とを用いて連結しても良い。第１のねじ山５１は、小径部材３ｄの円環部５０ｂの外周面に形成されている。
【０１２９】
第２のねじ山５２は、大径部材３ｅの内周面に形成されている。第１のねじ山５１と第２のねじ山５２とは互いに螺合する。基端部５５は、勿論大径部材３ｅに設けられ、第２のねじ山５２より小径部材３ｄ寄りに配されている。基端部５５の内径Ｄ２は、小径部材３ｄの円環部５０ｂの外径ｄ２より若干小さい。基端部５５の内径Ｄ２と小径部材３ｄの円環部５０ｂの外径ｄ２との差は、０．０１ｍｍ以上でかつ０．０５ｍｍ以下の範囲であるのが望ましい。なお、小径部材３ｄの円環部５０ｂの外径ｄ２は、小径部材３ｄの外径ｄ２である。
【０１３０】
この場合、大径部材３ｅと小径部材３ｄとを連結する際に、第１のねじ山５１と第２のねじ山５２とを螺合させる。すると、前記基端部５５の内径Ｄ２が小径部材３ｄの円環部５０ｂの外径ｄ２より若干小さいので、該基端部５５内に小径部材３ｄが圧入される。そして、外電極３が組み立てられる。
【０１３１】
前述した実施形態と同様に、大径部材２ｂと小径部材２ａとを別々に製造できるので、外電極３の材料歩留まりの悪化と、加工にかかる所用時間を抑制できる。したがって、外電極３のコストの高騰を抑制して、抵抗率計の電極１のコストの高騰を抑制できる。また、基端部５５の内径Ｄ２が小径部材３ｄの円環部５０ｂの外径ｄ２より若干小さい。このため、第１のねじ山５１と第２のねじ山５２とに接着剤を塗布することなく、大径部材３ｅと小径部材３ｄとを固定できる。したがって、接着剤を用いる必要がないので、大径部材３ｅと小径部材３ｄとを確実に電気的に接続でき、電解質液の抵抗率を確実に測定できる。
【０１３２】
また、外電極３の大径部材３ｅと小径部材３ｄとを、図１１に示すように、凸部５８ｂと、該凸部５８ｂが係合する凹部５９ｂとを用いて連結しても良い。凸部５８ｂは、大径部材３ｅの基端部５５の内周面から凸に形成されている。凹部５９ｂは、小径部材３ｄの円環部５０ｂの外周面から凹に形成されている。
【０１３３】
また、この場合、大径部材３ｅの基端部５５の内径Ｄ２は、小径部材３ｄの円環部５０ｂの外径ｄ２より若干小さいのが望ましい。大径部材３ｅの基端部５５の内径Ｄ２と小径部材３ｄの円環部５０ｂの外径ｄ２との差は、０．０１ｍｍ以上でかつ０．０３ｍｍ以下の範囲であるのが望ましい。また、前記凸部５８ｂの内周面からの突出量と、凹部５９ｂの外周面からの深さは、前記寸法の半分の０．００５ｍｍ〜０．０１５ｍｍ程度であるのが望ましい。
【０１３４】
この場合、大径部材３ｅと小径部材３ｄとを連結する際に、大径部材３ｅの基端部５５の内側に小径部材３ｄの円環部５０ｂを挿入する。すると、前記基端部５５の内径Ｄ２が小径部材３ｄの円環部５０ｂの外径ｄ２より若干小さいので、該基端部５５内に小径部材３ｄが圧入される。そして、凸部５８ｂが凹部５９ｂに係合して、外電極３が組み立てられる。
【０１３５】
前述した実施形態と同様に、大径部材３ｅと小径部材３ｄとを別々に製造できるので、外電極３の材料歩留まりの悪化と、加工にかかる所用時間を抑制できる。したがって、外電極３のコストの高騰を抑制して、抵抗率計の電極１のコストの高騰を抑制できる。また、基端部５５の内径Ｄ２が小径部材３ｄの円環部５０ｂの外径ｄ２より若干小さくかつ凸部５８ｂと凹部５９ｂとが互いに係合する。このため、接着剤を塗布することなく、大径部材３ｅと小径部材３ｄとを固定できる。したがって、接着剤を用いる必要がないので、大径部材３ｅと小径部材３ｄとを確実に電気的に接続でき、電解質液の抵抗率を確実に測定できる。
【０１３６】
また、図１１に示すように、凸部５８ｂと凹部５９ｂとを用いて、大径部材３ｅと小径部材３ｄとを固定する場合には、凸部５８ｂを小径部材３ｄの円環部５０ｂの外周面から凸に形成し、凹部５９ｂを大径部材３ｅの基端部５５の内周面から凹に形成しても良い。
【０１３７】
さらに、前述した実施形態では、リンス工程における洗浄液としての超純水の純度を測定するために用いられる場合を示しているが、本発明の電極１は超純水を製造する純水製造装置にも用いることができる。この場合、例えば、前記管部６１ａは超純水の原料となる純水（前述した超純水ほどではないが意図的に不純物を少なくした水：高純度水とも呼ぶ）の供給源と連結している。管部６１ｂは、純水製造装置に連結している。
【０１３８】
電極１は、純水製造装置に用いられた場合でも、前記管継手６０内に金属や樹脂からなる塵（パーティクル）が侵入することなく取り付けることができる。このため、純水製造装置のイオン交換樹脂やフィルターが劣化することを抑制でき、速やかに目的の純水を得ることができる。したがって、前記純水の純度を正確に測定できかつ超純水の製造にかかるコストの高騰を抑制できる。
【０１３９】
【発明の効果】
以上説明したように請求項１に記載の本発明によれば、少なくとも一つの電極部材が、大径部材と小径部材とを備えている。これらが連結している。このため、大径部材と小径部材とを別々に製造して、これらを連結して、前記電極部材を製造できる。大径部材と小径部材とを別々に製造できるので、電極部材の材料歩留まりの悪化を抑制できる。したがって、電極部材のコストの高騰を抑制して、抵抗率計の電極のコストの高騰を抑制できる。
【０１４０】
第１のねじ山と第２のねじ山とを螺合させると、大径部材と小径部材のいずれか一方の圧入部が他方に圧入される。このため、大径部材と小径部材とに接着剤を塗布して、これらの部材を互いに固定する際にも、大径部材の母材と小径部材の母材とが確実に接触する。したがって、大径部材と小径部材とが確実に電気的に接続する。したがって、電極部材の材料歩留まりの悪化を抑制して、コストの高騰を抑制できることにくわえ、電解質液の抵抗率を確実に測定できる。
【０１４１】
請求項２に記載の本発明によれば、圧入部が他方に食い込むので、大径部材と小径部材とに接着剤を塗布して、これらの部材を互いに固定する際にも、大径部材の母材と小径部材の母材とが確実に接触する。したがって、大径部材と小径部材とが確実に電気的に接続する。したがって、電極部材の材料歩留まりの悪化を抑制して、コストの高騰を抑制できることにくわえ、電解質液の抵抗率を確実に測定できる。
【０１４２】
請求項３に記載の本発明によれば、第１のねじ山より大径部材寄りに配された圧入部の外径が大径部材の内径より大きい。このため、大径部材と小径部材とに接着剤を塗布することなく、これらの部材を互いに固定できる。したがって、大径部材と小径部材とが確実に電気的に接続する。したがって、電極部材の材料歩留まりの悪化を抑制して、コストの高騰を抑制できることにくわえ、電解質液の抵抗率を確実に測定できる。
【０１４３】
請求項４に記載の本発明によれば、第２のねじ山より小径部材寄りに配された圧入部の内径が小径部材の外径より小さい。このため、大径部材と小径部材とに接着剤を塗布することなく、これらの部材を互いに固定できる。したがって、大径部材と小径部材とが確実に電気的に接続する。したがって、電極部材の材料歩留まりの悪化を抑制して、コストの高騰を抑制できることにくわえ、電解質液の抵抗率を確実に測定できる。
【０１４４】
請求項５に記載の本発明によれば、大径部材の内周面と小径部材の外周面のうち一方から凹の凹部に、他方から凸の凸部が係合する。このため、大径部材と小径部材とに接着剤を塗布することなく、これらの部材を互いに固定できる。したがって、大径部材と小径部材とが確実に電気的に接続する。したがって、電極部材の材料歩留まりの悪化を抑制して、コストの高騰を抑制できることにくわえ、電解質液の抵抗率を確実に測定できる。
【０１４５】
請求項６に記載の本発明によれば、内電極が大径部材と小径部材とを備えている。このため、大径部材と小径部材とを別々に製造して、これらを連結して、前記内電極を製造できる。大径部材と小径部材とを別々に製造できるので、内電極の材料歩留まりの悪化を抑制できる。したがって、内電極のコストの高騰を抑制して、抵抗率計の電極のコストの高騰を抑制できる。
【０１４６】
請求項７に記載の本発明によれば、外電極が大径部材と小径部材とを備えている。このため、大径部材と小径部材とを別々に製造して、これらを連結して、前記外電極を製造できる。大径部材と小径部材とを別々に製造できるので、外電極の材料歩留まりの悪化を抑制できる。したがって、外電極のコストの高騰を抑制して、抵抗率計の電極のコストの高騰を抑制できる。
【０１４７】
請求項８に記載の本発明によれば、内外電極が大径部材と小径部材とを備えている。このため、大径部材と小径部材とを別々に製造して、これらを連結して、前記内外電極それぞれを製造できる。大径部材と小径部材とを別々に製造できるので、内外電極の材料歩留まりの悪化を抑制できる。したがって、内外電極のコストの高騰を抑制して、抵抗率計の電極のコストの高騰を抑制できる。
【図面の簡単な説明】
【図１】本発明の一実施形態にかかる抵抗率計の電極の全体構成を示す断面図である。
【図２】図１に示された電極の要部を拡大して示す断面図である。
【図３】図１に示された電極の内外電極の断面図である。
【図４】図３に示された内電極の大径部材と小径部材との連結箇所を拡大して示す断面図である。
【図５】図４に示された内電極の大径部材と小径部材とを連結する工程を示す断面図である。
【図６】図３に示された外電極の大径部材と小径部材との連結箇所を拡大して示す断面図である。
【図７】図６に示された外電極の大径部材と小径部材とを連結する工程を示す断面図である。
【図８】図４に示された内電極の大径部材と小径部材との連結箇所の変形例を拡大して示す断面図である。
【図９】図４に示された内電極の大径部材と小径部材との連結箇所の他の変形例を拡大して示す断面図である。
【図１０】図６に示された外電極の大径部材と小径部材との連結箇所の変形例を拡大して示す断面図である。
【図１１】図６に示された外電極の大径部材と小径部材との連結箇所の他の変形例を拡大して示す断面図である。
【図１２】従来の抵抗率計の電極の全体構成を示す断面図である。
【符号の説明】
１ 抵抗率計の電極
２ 内電極（電極部材）
２ａ 小径部材
２ｂ 大径部材
３ 外電極（電極部材）
３ｄ 小径部材
３ｅ 大径部材
４１ 第１のねじ山
４２ 第２のねじ山
４３ 突起（圧入部）
４４ 小径部材の先端部（圧入部、一端部）
４６，４７ 面
５０ｂ 円環部（一端部）
５１ 第１のねじ山
５２ 第２のねじ山
５３ 突起（圧入部）
５５ 大径部材の基端部（圧入部）
５６，５７ 面
５８ａ，５８ｂ 凸部
５９ａ，５９ｂ 凹部
Ｄ１ 先端部の外径
Ｄ２ 基端部の内径
ｄ１ 大径部材の内径
ｄ２ 小径部材の円環部の外径（小径部材の外径）
ｔ 所定間隔[0001]
BACKGROUND OF THE INVENTION
This invention is a resistivity meter used in semiconductor cleaning equipment, industrial machinery, agriculture, food, medical-related water quality management, insulation of cooling water in nuclear power plants, concentration management of various chemicals, etc. It relates to an electrode.
[0002]
[Prior art]
Purity of ultrapure water and electrolyte solution in water quality management in various fields such as semiconductor cleaning equipment, industrial machinery, agriculture, food and medical, insulation of cooling water in nuclear power plants and concentration management of various chemicals In order to measure the concentration, a resistivity meter that measures the resistivity of the ultrapure water or the electrolyte solution is used.
[0003]
For example, in a semiconductor manufacturing process, a semiconductor wafer as an object to be cleaned is inserted into a cleaning tank and cleaned with a cleaning liquid such as ammonia (cleaning process). Then, the semiconductor wafer is rinsed by rinsing the semiconductor wafer while discharging the ammonia and putting ultrapure water (water deliberately extremely reducing impurities: also called ultrahigh purity water) into a cleaning tank. In the rinsing step, when measuring the purity of ultrapure water replaced with ammonia, for example, a resistivity meter including the electrode 101 shown in FIG. 12 is used.
[0004]
The electrode 101 of the resistivity meter illustrated in FIG. 12 includes an inner electrode 102, an outer electrode 103, and a support portion 104 that supports the inner electrode 102 and the outer electrode 103. The inner electrode 102 is made of a conductive metal. The inner electrode 102 is formed in a circular tube shape in which one end portion (hereinafter referred to as a tip portion) 102b is closed. The inner electrode 102 is integrally provided with a large diameter portion 105 and a small diameter portion 106. The outer diameter of the small diameter portion 106 is smaller than the outer diameter of the large diameter portion 105. The large diameter portion 105 and the small diameter portion 106 are coaxial with each other and arranged in series with each other.
[0005]
The outer electrode 103 is made of a conductive metal. The outer electrode 103 is formed in a circular tube shape. The inner diameter of the outer electrode 103 is larger than the outer diameter of the inner electrode 102. The inner electrode 102 is inserted into the outer electrode 103, and the inner and outer electrodes 102 and 103 are arranged coaxially with each other. The support portion 104 supports the proximal end portion 102 a of the small diameter portion 106 of the inner electrode 102 and the proximal end portion 103 a of the outer electrode 103.
[0006]
With the above-described configuration, the electrode 101 of the resistivity meter has at least the tip portions 102b and 103b of the inner electrode 102 and the outer electrode 103 disposed in the flow path of the electrolyte solution to be measured, and these electrodes 102 and 103 are arranged. The resistivity of the electrolyte solution is measured by measuring the electrical resistance between them. And based on the measured resistivity, the purity of electrolyte solution, such as ultrapure water, is calculated | required.
[0007]
[Problems to be solved by the invention]
The inner electrode 102 as an electrode member of the electrode 101 of the resistivity meter is made of a conductive metal and integrally includes a large diameter portion 105 and a small diameter portion 106 having different outer diameters. For this reason, the inner electrode 102 has been manufactured, for example, by subjecting a cylindrical member made of the metal to cutting. For this reason, there are very many parts that are wasted (the material yield is greatly deteriorated).
[0008]
Further, since it is necessary to make a hole 107 over the large diameter portion 105 and the small diameter portion 106, it is very difficult to manufacture. For this reason, the man-hour required for manufacture tends to increase. Therefore, the cost of the electrode 101 of the resistivity meter tended to increase.
[0009]
Accordingly, an object of the present invention is to provide an electrode of a resistivity meter that can suppress an increase in cost.
[0010]
[Means for Solving the Problems]
In order to solve the above-mentioned problems and achieve the object, the electrode of the resistivity meter according to claim 1 has a plurality of electrode members arranged at predetermined intervals in the flow path of the electrolyte solution to be measured. In the resistivity meter electrode for measuring the resistivity of the electrolyte solution based on the electrical resistance between the electrode members, at least one of the plurality of electrode members is formed in a circular tubular shape with respect to each other. Large-diameter members and small-diameter members having different diameters, and these large-diameter members and small-diameter members are coaxially connected to each other. The first thread is formed on the outer peripheral surface of the small-diameter member, and the second screw thread is formed on the inner peripheral surface of the large-diameter member. When the screw thread and the second screw thread are screwed together, the screw thread is formed on one of the large-diameter member and the small-diameter member and has a press-fit portion that press-fits the other. It is characterized by that.
[0012]
Claim 2 The electrode of the resistivity meter of the present invention described in claim 1 In the electrode of the resistivity meter, the large-diameter member and the small-diameter member each include a surface that faces each other when connected to each other, and the press-fitting portion includes a surface of the large-diameter member and a surface of the small-diameter member The protrusion protrudes from one side to the other, and when the first screw thread and the second screw thread are screwed together, the protrusion is difficult to insert into the other.
[0013]
Claim 3 The electrode of the resistivity meter of the present invention described in claim 1 In the electrode of the resistivity meter, the press-fitting portion is provided in the small-diameter member and provided closer to the large-diameter member than the first screw thread, and has an outer diameter larger than an inner diameter of the large-diameter member. It is characterized by being.
[0014]
Claim 4 The electrode of the resistivity meter of the present invention described in claim 1 In the resistivity meter electrode described above, the press-fitting portion is provided on the large-diameter member and is provided closer to the small-diameter member than the second thread, and has an inner diameter smaller than an outer diameter of the small-diameter member. It is characterized by that.
[0015]
Claim 5 The electrode of the resistivity meter of the present invention described in In the electrode of a resistivity meter, a plurality of electrode members are arranged at predetermined intervals in the flow path of the electrolyte solution to be measured, and the resistivity of the electrolyte solution is measured based on the electrical resistance between the electrode members. At least one of the plurality of electrode members has a large-diameter member and a small-diameter member formed in a circular tube shape and having different outer diameters, and the large-diameter member and the small-diameter member are coaxial with each other. Concatenate, One end of the small-diameter member is inserted inside the large-diameter member so that the large-diameter member and the small-diameter member are connected, and one of the inner peripheral surface of the large-diameter member and the outer peripheral surface of the small-diameter member Recessed Part is formed, the other Convex A portion is formed, and when the one end portion of the small-diameter member is inserted inside the large-diameter member, the convex portion engages in the concave portion.
[0016]
Claim 6 An electrode of a resistivity meter according to the present invention described in claim 1 is defined in claims 1 to 5 In the electrode of the resistivity meter according to any one of the above, the electrode member includes a circular inner electrode and a circular outer electrode, and the inner electrode is inserted inside the outer electrode, The inner and outer electrodes are arranged coaxially with each other, and the inner electrode has the large-diameter member and the small-diameter member.
[0017]
Claim 7 An electrode of a resistivity meter according to the present invention described in claim 1 is defined in claims 1 to 5 In the electrode of the resistivity meter according to any one of the above, the electrode member includes a circular inner electrode and a circular outer electrode, and the inner electrode is inserted inside the outer electrode, The inner and outer electrodes are arranged coaxially with each other, and the outer electrode has the large-diameter member and the small-diameter member.
[0018]
Claim 8 An electrode of a resistivity meter according to the present invention described in claim 1 is defined in claims 1 to 5 In the electrode of the resistivity meter according to any one of the above, the electrode member includes a circular inner electrode and a circular outer electrode, and the inner electrode is inserted inside the outer electrode, The inner and outer electrodes are arranged coaxially with each other, and both the inner electrode and the outer electrode have the large-diameter member and the small-diameter member.
[0019]
According to the electrode of the resistivity meter of the present invention described in claim 1, at least one electrode member includes a large-diameter member and a small-diameter member. These large-diameter members and small-diameter members are connected. For this reason, a large diameter member and a small diameter member can be manufactured separately, and these can be connected, and the said electrode member can be manufactured.
[0020]
First When the first screw thread and the second screw thread are screwed together, either one of the large-diameter member and the small-diameter member is press-fitted into the other. Therefore, when the adhesive is applied to the large-diameter member and the small-diameter member and these members are fixed to each other, the base material of the large-diameter member and the base material of the small-diameter member are reliably in contact with each other.
[0021]
Claim 2 According to the electrode of the resistivity meter of the present invention described in the above, since the press-fit portion bites into the other, the adhesive is applied to the large-diameter member and the small-diameter member to fix the members to each other. The base material of the diameter member and the base material of the small diameter member are reliably in contact with each other.
[0022]
Claim 3 According to the electrode of the resistivity meter of the present invention described in the above, the outer diameter of the press-fitting portion closer to the larger diameter member than the first thread is larger than the inner diameter of the large diameter member. For this reason, these members can be fixed to each other without applying an adhesive to the large diameter member and the small diameter member.
[0023]
Claim 4 According to the electrode of the resistivity meter of the present invention described in the above, the inner diameter of the press-fitting portion arranged closer to the small diameter member than the second thread is smaller than the outer diameter of the small diameter member. For this reason, these members can be fixed to each other without applying an adhesive to the large diameter member and the small diameter member.
[0024]
Claim 5 According to the electrode of the resistivity meter of the present invention described above, the convex portion engages with the concave portion which is concave from one to the concave portion which is concave from one of the inner peripheral surface of the large diameter member and the outer peripheral surface of the small diameter member. For this reason, these members can be fixed to each other without applying an adhesive to the large diameter member and the small diameter member.
[0025]
Claim 6 According to the electrode of the resistivity meter of the present invention described in the above, the inner electrode includes a large diameter member and a small diameter member. For this reason, a large diameter member and a small diameter member can be manufactured separately, and these can be connected, and the said inner electrode can be manufactured.
[0026]
Claim 7 According to the electrode of the resistivity meter of the present invention described in the above, the outer electrode includes the large diameter member and the small diameter member. For this reason, a large-diameter member and a small-diameter member can be manufactured separately, and these can be connected to manufacture the outer electrode.
[0027]
Claim 8 According to the electrode of the resistivity meter of the present invention described in 1., the inner and outer electrodes are provided with a large diameter member and a small diameter member. For this reason, a large-diameter member and a small-diameter member can be manufactured separately, and these can be connected to manufacture each of the inner and outer electrodes.
[0028]
DETAILED DESCRIPTION OF THE INVENTION
An electrode 1 of a resistivity meter according to an embodiment of the present invention will be described with reference to FIGS. The electrode 1 of the resistivity meter shown in FIG. 1 and the like is used for semiconductor cleaning equipment, industrial machinery, agriculture, food, medical-related water quality management such as ultrapure water, and insulation of cooling water for nuclear power plants. It is used for concentration control of various chemical solutions as an electrolyte solution.
[0029]
The electrode 1 has, for example, the purity of ultrapure water (corresponding to an electrolyte solution described in claims) as a cleaning liquid in a rinsing process in a semiconductor manufacturing process for cleaning an object to be cleaned such as a semiconductor wafer. Used to measure. The resistivity meter using the electrode 1 is a device that measures the resistivity of the electrolyte solution in order to measure the purity of the electrolyte solution such as the above-described ultrapure water as a measurement object.
[0030]
The electrode 1 is disposed in a flow path such as the ultrapure water, and is attached to a T-shaped pipe joint 60 constituting the flow path as shown in FIG. As shown in FIG. 1, the T-shaped pipe joint 60 includes pipe portions 61a, 61b, and 61c that constitute the flow path.
[0031]
A cleaning tank or the like for housing a semiconductor wafer and performing the cleaning process, the rinsing process, and the like is connected to the one pipe portion 61a. The other pipe portion 61b is connected to a discharge pipe for discharging the processing liquid used in the above-described cleaning process and rinsing process. The electrode 1 is attached to the other one pipe part 61c. A taper screw 62 or the like as a thread is formed on the outer peripheral surface of the tube portion 61c.
[0032]
As shown in FIG. 1, the electrode 1 of the resistivity meter includes an inner electrode 2 as an electrode member, an outer electrode 3 as an electrode member, a seal member 8, and a support that supports the inner electrode 2 and the outer electrode 3. Unit 4, temperature detection unit 5, inner electrode lead wire 6 as an electric wire electrically connected to the inner electrode 2, outer electrode lead wire 7 as an electric wire electrically connected to the outer electrode 3, A cap nut 71 as attachment means, a coil spring 72 as urging means, and a seal projection 33 are provided.
[0033]
The inner electrode 2 is made of a conductive metal or the like. The inner electrode 2 is formed in a circular tube shape in which one end portion (hereinafter referred to as a tip portion) 2g is closed. The inner electrode 2 includes a small-diameter member 2a having a relatively small outer diameter and a large-diameter member 2b having a relatively large outer diameter, as shown in FIGS. The small diameter member 2a and the large diameter member 2b are coaxial with each other and connected in series.
[0034]
The large-diameter member 2b is made of a high-strength and corrosion-resistant metal such as titanium. The large-diameter member 2b is formed in a circular tube shape in which the distal end portion 2g is closed, and has an outer diameter that is substantially constant over the entire length. The small diameter member 2a is made of a metal such as stainless steel, for example. The small diameter member 2a is formed in a circular tube shape. The small diameter member 2a has an outer diameter that is substantially constant over the entire length. The small-diameter member 2a includes a concave groove 2h formed concave from the outer surface. The concave groove 2h is formed along the circumferential direction of the small diameter member 2a.
[0035]
As shown in FIG. 3, the large-diameter member 2b and the small-diameter member 2a are connected in series by a first thread 41, a second thread 42, and a protrusion 43 (shown in FIG. 4) as a press-fit portion. Is done. The first screw thread 41 is formed on the outer peripheral surface of one end (hereinafter referred to as the tip) 44 of the small diameter member 2a. For this reason, the small diameter member 2a is a so-called male screw.
[0036]
The second screw thread 42 is formed on the inner peripheral surface of the other end portion (hereinafter referred to as a base end portion) 45 of the large-diameter member 2b. For this reason, the large diameter member 2b is a so-called female screw. The first thread 41 is screwed into the second thread 42. That is, the first thread 41 and the second thread 42 are screwed together.
[0037]
The small-diameter member 2a and the large-diameter member 2b include surfaces 46 and 47 that face each other and overlap each other when the first thread 41 and the second thread 42 are screwed together. These surfaces 46 and 47 are annular and flat along a direction orthogonal to the axis of the small-diameter member 2a and the large-diameter member 2b, that is, the axis of the inner electrode 2.
[0038]
The protrusion 43 protrudes from one of the surface 46 of the small diameter member 2a and the surface 47 of the large diameter member 2b toward the other. In the illustrated example, as shown in FIG. 4, the protrusion 43 is formed so as to protrude from the surface 46 of the small diameter member 2a toward the surface 47 of the large diameter member 2b. The protrusion 43 has an annular shape. The cross-sectional shape of the protrusion 43 is formed in a mountain shape with a sharp point.
[0039]
The inner electrode 2 is obtained by connecting the first thread 41 and the second thread 42 to each other and connecting the small diameter member 2a and the large diameter member 2b in series. When these first screw threads 41 and second screw threads 42 are screwed together, an adhesive is applied to these screw threads 41 and 42. Furthermore, since the threads 41 and 42 are pointed when they are screwed together, as shown in FIG. 4, the protrusion 43 is difficult to insert into the base material of the large-diameter member 2b.
[0040]
When assembling the inner electrode 2 having the above-described configuration, first, an adhesive is applied to the first screw thread 41 and the second screw thread 42. As shown in FIG. 5A, the first screw thread 41 is gradually screwed into the second screw thread 42 and is gradually inserted into the large diameter member 2b from the distal end portion 44 of the small diameter member 2a.
[0041]
Then, as shown in FIG.5 (b), the protrusion 43 contacts the surface 47 of the large diameter member 2b. Further, when the first screw thread 41 is screwed into the second screw thread 42, as shown in FIG. 5C, the protrusion 43 gradually bites into the base material of the large diameter member 2b. Then, as shown in FIG. 4, the surfaces 46 and 47 face each other and overlap so that the small diameter member 2a and the large diameter member 2b are fixed to obtain the inner electrode 2 having the above-described configuration.
[0042]
The inner electrode 2 is arranged in a state where the large diameter member 2b is located on the distal end side of the electrode 1 of the resistivity meter and the small diameter member 2a is located on the proximal end side. Inside the small-diameter member 2a and the large-diameter member 2b of the inner electrode 2 forms a temperature detecting portion insertion hole 2d.
[0043]
The temperature detecting portion insertion hole 2d is coaxially arranged with the small diameter member 2a and the large diameter member 2b. The temperature detection portion insertion hole 2 d is formed across the end surface 2 c on the proximal end portion 2 f side of the inner electrode 2 and the distal end portion 2 g of the inner electrode 2. Needless to say, the temperature detecting portion insertion hole 2d is open on the end surface 2c on the base end portion 2f side, but is not open on the end surface 2e on the tip end portion 2g side of the inner electrode 2.
[0044]
The outer electrode 3 is made of a conductive metal or the like. The outer electrode 3 is formed in a circular tube shape. As shown in FIGS. 2 and 3, the outer electrode 3 includes a small-diameter member 3 d having a relatively small inner and outer diameter and a large-diameter member 3 e having a relatively large inner and outer diameter.
[0045]
The large diameter member 3e is formed so that the inner and outer diameters are substantially constant over the entire length. The inner diameter of the large diameter member 3e is larger than the outer diameter of the large diameter member 2b of the inner electrode 2. The large-diameter member 3e has a plurality of through-holes 48 through which the above-described electrolyte solution passes in the base end portion 55. The through hole 48 passes through the large diameter member 3e. Further, a step 49 is formed in which the inner diameter of the large-diameter member 3e increases stepwise from the base end portion 55 toward the tip end portion 3c. The step 49 is provided near the tip 3 c of the through hole 48.
[0046]
As shown in FIGS. 2 and 3, the small-diameter member 3d is integrally provided with a circular tube portion 50a and an annular ring portion 50b. The circular pipe part 50a is formed so that the inner and outer diameters are substantially constant over the entire length. The inner diameter of the circular pipe portion 50 a is larger than the outer diameter of the small diameter member 2 a of the inner electrode 2.
[0047]
The annular portion 50b is connected to one end portion (hereinafter referred to as a tip portion) of the circular pipe portion 50a. The annular portion 50b is coaxial with the circular tube portion 50a. For this reason, the annular part 50b protrudes from the front-end | tip part of the circular pipe part 50a to the outer peripheral direction of this circular pipe part 50a over the perimeter of the circular pipe part 50a. The outer diameter of the annular portion 50b is substantially equal to the inner diameter of the large diameter member 3e. Further, the annular portion 50b is integrally formed with a flange portion 50c that protrudes further in the outer peripheral direction from the outer peripheral surface. Further, the annular portion 50b constitutes one end portion of the small diameter member 3d described in this specification.
[0048]
As shown in FIG. 3, the small diameter member 3d and the large diameter member 3e are coaxial with each other by a first thread 51, a second thread 52, and a protrusion 53 (shown in FIG. 6) as a press-fit portion. And connected in series. When the first screw thread 51 and the second screw thread 52 are screwed together as will be described later, the annular portion 50b that connects the small diameter member 3d and the large diameter member 3e to each other has an inner and outer electrode as described later. When 2 and 3 are arranged coaxially with each other, they become parallel to the stepped portion 2 i of the inner electrode 2.
[0049]
The first thread 51 is formed on the outer peripheral surface of the annular portion 50b of the small diameter member 3d. For this reason, the small diameter member 3d is a so-called male screw. The second thread 52 is formed on the inner peripheral surface of the base end portion 55 of the large-diameter member 3e. For this reason, the large-diameter member 3e is a so-called female screw. The first screw thread 51 is screwed into the second screw thread 52. That is, the first thread 51 and the second thread 52 are screwed together.
[0050]
The small-diameter member 3d and the large-diameter member 3e include surfaces 56 and 57 that face each other and overlap each other when the first screw thread 51 and the second screw thread 52 are screwed together. These surfaces 56 and 57 are annular and flat along a direction orthogonal to the axis of the small diameter member 2a and the large diameter member 2b, that is, the axis of the inner electrode 2.
[0051]
The surface 56 of the small diameter member 3d is the surface of the flange portion 50c. The surface 57 of the large diameter member 3e is an end surface of the large diameter member 3e on the base end portion 55 side. The protrusion 53 protrudes from one of the surface 56 of the small diameter member 3d and the surface 57 of the large diameter member 3e toward the other. In the illustrated example, as shown in FIG. 6, the protrusion 53 is formed so as to protrude from the surface 57 of the large diameter member 3e toward the surface 56 of the small diameter member 3d. The protrusion 53 has an annular shape. The cross-sectional shape of the protrusion 53 is formed in a mountain shape with a sharp point.
[0052]
The outer electrode 3 is obtained by connecting the first thread 51 and the second thread 52 to each other and connecting the small diameter member 3d and the large diameter member 3e in series. When the first screw thread 51 and the second screw thread 52 are screwed together, an adhesive is applied to the screw threads 51 and 52. Further, since the threads 51 and 52 are sharp when they are screwed together, as shown in FIG. 6, the protrusion 53 is difficult to insert into the base material of the small diameter member 3 d.
[0053]
When assembling the outer electrode 3 having the above-described configuration, first, a through hole 48 is formed in the peripheral wall of a cylindrical member having a constant inner and outer diameter constituting the large-diameter member 3e. Thereafter, the step 49 is formed by cutting the inner peripheral surface. Thereafter, the second thread 52 is formed on the inner peripheral surface of the large-diameter member 3e, and the first thread 51 is formed on the outer peripheral surface of the annular portion 50b of the small-diameter member 3d.
[0054]
Adhesive is applied to the first thread 51 and the second thread 52. As shown in FIG. 7A, the first thread 51 is gradually screwed into the second thread 52, and the small diameter member 3d is gradually inserted into the large diameter member 3e.
[0055]
Then, as shown in FIG.7 (b), the protrusion 53 contacts the surface 56 of the small diameter member 3d. Further, when the first screw thread 51 is screwed into the second screw thread 52, the protrusion 53 gradually bites into the base material of the small diameter member 3d as shown in FIG. 7C. Then, as shown in FIG. 6, the surfaces 56 and 57 face each other and overlap so that the small-diameter member 3d and the large-diameter member 3e are fixed to obtain the outer electrode 3 having the above-described configuration.
[0056]
As shown in FIG. 3, the inner electrode 2 and the outer electrode 3 are arranged in such a manner that the small diameter member 2a is disposed in the small diameter member 3d and the large diameter member 2b is disposed in the large diameter member 3e. That is, the inner electrode 2 and the outer electrode 3 are coaxially arranged with the inner electrode 2 inserted inside the outer electrode 3. The inner electrode 2 is arranged in a state in which the end surface 2e of the large-diameter member 2b is located slightly on the back side of the outer electrode 3 with respect to the end surface 3a located on the distal end portion 3c side of the outer electrode 3.
[0057]
The seal member 8 is made of a synthetic resin having plastomer properties, that is, not having elastomer properties. That is, the seal member 8 hardly undergoes elastic deformation. The seal member 8 is made of a polymer material having high plasticity. In the present embodiment, the seal member 8 is made of the above-described non-eluting fluororesin or the like with a small amount of substance that elutes with respect to the electrolyte solution. That is, the seal member 8 is non-eluting.
[0058]
As shown in FIGS. 1 to 3, the seal member 8 is integrally provided with a disc portion 8a and a cylindrical portion 8b. The disc portion 8a is formed in a disc shape having a circular planar shape and a substantially constant thickness, and both surfaces of the disc portion 8a are formed flat. The disc portion 8 a has an outer diameter that is substantially equal to the inner diameter of the large-diameter member 3 e of the outer electrode 3.
[0059]
The disc portion 8a has a hole 8c in the center. The hole 8c passes through the disc portion 8a. The hole 8c has a circular planar shape. The hole 8 c has an inner diameter that is substantially equal to the outer diameter of the small-diameter member 2 a of the inner electrode 2.
[0060]
The cylinder part 8b is continued to the edge of the hole 8c. The cylinder portion 8b is formed in a cylindrical shape. The cylinder portion 8b is erected with respect to the disc portion 8a. The cylindrical portion 8 b is formed so that the inner diameter is substantially equal to the outer diameter of the small diameter member 2 a of the inner electrode 2. The cylindrical part 8 b is formed so that the outer diameter is substantially equal to the inner diameter of the circular pipe part 50 a of the small diameter member 3 d of the outer electrode 3. The cylindrical portion 8b is fitted to both the outer periphery of the small diameter member 2a and the inner periphery of the small diameter member 3d, and keeps the interval between the electrodes 2 and 3 at a predetermined interval t.
[0061]
When the support portion 4 supports the base end portions 2f and 3b of the electrodes 2 and 3, the disc portion 8a and the stepped portion 2i are formed as shown in FIGS. The cylindrical portion 8b is disposed between the small-diameter members 2a and 3d.
[0062]
At this time, since the seal member 8 hardly elastically deforms and both surfaces of the disk portion 8a are formed flat, the both surfaces are in contact with both the stepped portion 2i and the annular portion 50b without any gaps, The cylindrical portion 8b is in contact with both the small diameter members 2a and 3d without a gap. The seal member 8 keeps the space between the inner and outer electrodes 2 and 3 liquid-tight and prevents the electrolyte solution from entering the space 16 described later from between the inner and outer electrodes 2 and 3.
[0063]
The support 4 includes an end 2f (referred to as a base end) near the small diameter member 2a of the inner electrode 2 and an end 3b (referred to as a base end) near the small diameter member 3d of the outer electrode 3. Support both sides. The support portion 4 includes an outer electrode holder 11 as a support portion main body, a base end cap 12, and the like.
[0064]
The outer electrode holder 11 is made of a synthetic resin having an insulating property and a small amount of a substance that elutes from the electrolyte solution, that is, a non-eluting material. Fluorine such as polyphenylene sulfide (hereinafter referred to as PPS), polyetheretherketone (hereinafter referred to as PEEK), polytetrafluoroethylene (hereinafter referred to as PTFE) or the like as a synthetic resin constituting the outer electrode holder 11 Resin can be used.
[0065]
The outer electrode holder 11 is formed in a bottomed cylindrical shape including a disc portion 11c and a cylindrical portion 11d. The disk portion 11c has a circular planar shape. The disk portion 11c has a substantially flat surface. The outer diameter of the disc part 11c is formed substantially equal to the outer diameter of the end face 61d of the pipe part 61c.
[0066]
A hole 11e is provided in the center of the disc portion 11c. The hole 11e penetrates the disc part 11c. The hole 11e has a circular planar shape. The inner diameters of the holes 11e are formed to be approximately equal from one surface of the disc portion 11c toward the other surface. The hole 11 e is formed so that the inner diameter is substantially equal to the outer diameter of the circular pipe portion 50 a of the small diameter member 3 d of the outer electrode 3.
[0067]
The cylindrical portion 11d includes a small-diameter portion 11a and a large-diameter portion 11b that are formed in a cylindrical shape, have the same inner diameter, and are coaxially arranged in series. The large-diameter portion 11b is formed to have a larger outer diameter than the small-diameter portion 11a. The large diameter portion 11b is arranged closer to the disc portion 11c than the small diameter portion 11a. The large diameter portion 11b is continuous with the outer edge of the disc portion 11c. The cylinder part 11d is erected with respect to the disk part 11c.
[0068]
The outer electrode holder 11 is arranged with the small diameter member 3d of the outer electrode 3 inserted in the hole 11e. At this time, since the outer diameter of the circular pipe portion 50a of the small diameter member 3d is substantially constant along the longitudinal direction and the inner diameter of the hole 11e is substantially constant, and the outer electrode holder 11 is made of the above-described synthetic resin, The inner surface of the hole 11e and the outer surface of the small diameter member 3d are in close contact with each other without a gap.
[0069]
For this reason, the outer electrode holder 11, that is, the space between the support portion 4 and the outer electrode 3 is kept liquid-tight, and the electrolyte solution can enter the space 16 from between the outer electrode holder 11 and the outer electrode 3. Is prevented. Further, the concave groove 2 h is located on the base end portion 2 f side from the disc portion 11 c and is disposed in the space 16.
[0070]
The base end cap 12 is formed in a bottomed cylindrical shape having a disc portion 12a and a cylindrical portion 12b. The disc part 12a is formed in a disc shape. The cylindrical part 12b is formed in a cylindrical shape and continues to the periphery of the disk part 12a.
[0071]
The base end cap 12 is formed from a synthetic resin such as a known polyamide resin (nylon). The base end cap 12 is arranged such that the cylindrical portion 12 b is fitted to the outer periphery of the small diameter portion 11 a of the outer electrode holder 11. The base end cap 12 has the cylindrical portion 12b bonded and fixed to the small diameter portion 11a with a known epoxy adhesive.
[0072]
The base end cap 12 includes a round hole 12c that penetrates the disk portion 12a. The planar shape of the round hole 12c is formed in a substantially circular shape. The round hole 12c is arranged coaxially with the disk portion 12a. Inside the round hole 12c, a later-described wire bundle 26 of the temperature detection unit 5 passes.
[0073]
Moreover, the support part 4 forms the space 16 enclosed by the disc part 11c of the outer electrode holder 11, the cylinder part 11d, the disc part 12a of the base end cap 12, etc. in the inside.
[0074]
The support portion 4 further includes an insulating washer 20 disposed in the space 16, a retaining ring 19, a conductive holder 27 in which a disc portion 21 and a circular tube portion 22 are integrally formed, and a second urging force. A coil spring 9 is provided as means.
[0075]
The insulating washer 20 is made of a synthetic resin having an insulating property and is formed in an annular shape. The insulating washer 20 is formed so that the inner diameter is substantially equal to the outer diameter of the small diameter member 2 a and the outer diameter is substantially equal to or slightly smaller than the inner diameter of the conductive holder 27. The insulating washer 20 is fitted to the outer periphery of the small diameter member 2a. The insulating washer 20 is disposed between the end of the small diameter member 3d and the recessed groove 2h.
[0076]
The retaining ring 19 is made of a well-known steel having conductivity, such as stainless steel, and is formed in an annular shape. The retaining ring 19 is accommodated in the cylindrical portion 11d of the outer electrode holder 11 with the small-diameter member 2a of the inner electrode 2 passing inside.
[0077]
The inner edge of the retaining ring 19 is fitted in the concave groove 2h of the small diameter member 2a. The retaining ring 19 is in close contact with the surface of the insulating washer 20 near the end surface 2c. The retaining ring 19 prevents the insulating washer 20 from coming out of the proximal end portion 2f of the small diameter member 2a by fitting the inner edge into the concave groove 2h.
[0078]
The disc portion 21 of the conductive holder 27 is made of a conductive metal and is formed in a disc shape. The disk portion 21 of the conductive holder 27 has an inner diameter that is substantially equal to the outer diameter of the small-diameter member 3 d of the outer electrode 3. The disk portion 21 of the conductive holder 27 has an outer diameter that is substantially equal to the inner diameter of the cylindrical portion 11d. The disc portion 21 of the conductive holder 27 is overlapped with the disc portion 11 c in a state of fitting to the outer periphery of the small diameter member 3 d and fitting to the inner periphery of the outer electrode holder 11.
[0079]
The circular pipe portion 22 of the conductive holder 27 is made of a metal having conductivity and is formed in a circular tube shape. The circular pipe portion 22 of the conductive holder 27 has an inner diameter that is sufficiently larger than the outer diameter of the small diameter member 3d. The circular tube portion 22 of the conductive holder 27 has an outer diameter that is substantially equal to the inner diameter of the cylindrical portion 11d. An end of the circular tube portion 22 of the conductive holder 27 is integrally formed with the disc portion 21 of the conductive holder 27 and is inserted into the cylindrical portion 11d.
[0080]
The coil spring 9 has a relatively small spring constant. The coil spring 9 is made of a known steel such as stainless steel. The coil spring 9 is provided in the circular tube portion 22 of the conductive holder 27 and between the insulating washer 20 and the circular plate portion 21 of the conductive holder 27. The coil spring 9 is arranged in a state where the small diameter members 2a and 3d of the inner and outer electrodes 2 and 3 pass inside.
[0081]
The coil spring 9 urges the insulating washer 20 and the disk portion 21 of the conductive holder 27 toward each other in a direction away from each other. The coil spring 9 biases the insulating washer 20 and the disk portion 21 of the conductive holder 27 away from each other, and the insulating washer 20 is prevented from coming off from the base end portion 2 f by the retaining ring 19. The base end portion 2 f of the inner electrode 2 is biased so as to be accommodated in the support portion 4.
[0082]
The inner and outer electrodes 2, 3, the seal member 8, and the outer electrode holder 11 are biased so that the disc portion 11 c, the annular portion 50 b, the disc portion 8 a, and the stepped portion 2 i approach each other. As described above, the coil spring 9 biases the inner electrode 2 and the support portion 4 in the direction in which the distance between the base end portion 2 f of the inner electrode 2 and the support portion 4 becomes narrower.
[0083]
Moreover, since both the inner electrode 2 and the support part 4 are urged | biased so that a mutual space | interval may become narrow by the said coil spring 9, both the surfaces of the sealing member 8 are the level | step-difference part 2i, the annular part 50b, and Ensure close contact with both without any gaps. That is, the seal member 8 is in close contact with the inner and outer electrodes 2 and 3 without a gap. The seal member 8 keeps the inner and outer electrodes 2 and 3 in a liquid-tight state to prevent the above-described ultrapure water from entering the space 16.
[0084]
Furthermore, since both the inner electrode 2 and the support portion 4 are urged so that the distance between them is reduced by the coil spring 9, the disc portion 11c and the annular portion 50b are securely in close contact with each other without a gap. To do. The space between the disc portion 11c and the annular portion 50b is kept liquid-tight, and the above-described ultrapure water is prevented from entering the space 16.
[0085]
The space 16 is provided with the temperature detecting portion insertion hole 2d. Furthermore, the space 16 accommodates therein a conductive ring 23, a conductive wire 24, a ring 17 that is attached by being fitted to the inner peripheral surface of the circular pipe portion 22 of the conductive holder 27, and the like. .
[0086]
The conductive ring 23 is made of a conductive metal or the like and is formed in a circular tube shape. The conductive ring 23 has an inner diameter substantially equal to the outer diameter of the small diameter member 3d. The conductive ring 23 has an outer diameter that is sufficiently smaller than the inner diameter of the circular tube portion 22. The conductive ring 23 is fitted to the outer periphery of the end portion near the base end portion 3b of the small diameter member 3d.
[0087]
One end of the conductive wire 24 is fixed to the conductive ring 23 by brazing using solder or the like, and the other end is sandwiched between the disc portion 21 of the conductive holder 27 and the coil spring 9 (or the wire is directly or separately provided). It is fixed by soldering the part washer with solder. The conductive wire 24 electrically connects the conductive ring 23 and the conductive holder 27 to each other.
[0088]
In the illustrated example, the ring 17 includes an annular ring main body 17a and a claw 17b protruding from the outer edge of the ring main body 17a toward the outer peripheral direction. A plurality of claws 17b are provided. The claws 17b are arranged at substantially equal intervals along the circumferential direction of the ring body 17a.
[0089]
The ring 17 is fixed to the circular pipe portion 22 of the conductive holder 27 with the claws 17 b fitted into the inner peripheral surface of the circular pipe portion 22 of the conductive holder 27. The ring 17 is made of a known steel such as stainless steel. Further, the ring 17 may be fitted into a groove provided on the inner peripheral surface of the circular pipe portion 22 of the conductive holder 27 with the claw 17b.
[0090]
The temperature detector 5 includes a temperature sensor element (not shown), a circular tube spring member 25, and the like. The temperature detector 5 is disposed in the temperature detector insertion hole 2d. The temperature sensor element is arranged in the temperature detection part insertion hole 2d and at the tip 2g of the inner electrode 2. The temperature sensor element includes a temperature sensing unit that measures temperature.
[0091]
The temperature sensor element includes a thermistor having a temperature-sensitive portion having a disk shape, a pellet shape, or a surface portion similar to the disk shape, and a thin film type platinum temperature sensor. The temperature sensor element is disposed so that the surface portion of the temperature sensing portion is substantially parallel to the flow path of the electrolyte solution in the temperature detection portion insertion hole 2d. An electric wire (not shown) is attached to the temperature sensor element.
[0092]
The electric wire extends from the distal end portion 2g of the inner electrode 2 toward the proximal end portion 2f of the inner electrode 2, and is arranged in the temperature detection portion insertion hole 2d. Each of these electric wires is electrically connected to an arithmetic device (not shown).
[0093]
A portion extending from the center portion along the longitudinal direction of the electric wire (not shown) to the other end portion, the inner electrode lead wire 6 and the outer electrode lead wire 7 are bundled together to form an electric wire bundle 26. When the temperature detection unit 5 is accommodated in the temperature detection unit insertion hole 2d, the wire bundle 26 has a round hole 12c in the base end cap 12 located on the base end portions 2f and 3b side of the inner electrode 2 and the outer electrode 3. Through to the outside.
[0094]
The circular tube spring member 25 is made of a well-known steel having conductivity. The circular tube spring member 25 is formed in a circular tube shape. A part of the circular tube spring member 25 is cut along the longitudinal direction. The circular tube spring member 25 has a C-shaped cross section that intersects the longitudinal direction thereof. The circular tube spring member 25 has elasticity that allows its outer diameter to be expanded and contracted. The circular tube spring member 25 has an outer diameter larger than the inner diameter of the small-diameter member 2a of the inner electrode 2 in the initial state.
[0095]
The circular tube spring member 25 is disposed near the temperature sensor element of the wire bundle 26. The circular tube spring member 25 bundles the above-described electric wires (not shown). The circular tube spring member 25 is inserted into the small diameter member 2a against its elastic restoring force. When inserted into the small-diameter member 2a, the circular spring member 25 generates an elastic restoring force and comes into close contact with the inner peripheral surface of the small-diameter member 2a.
[0096]
The inner electrode lead wire 6 is accommodated in the space 16 and one end thereof is electrically connected to the circular tube spring member 25. The inner electrode lead wire 6 is electrically connected to the inner electrode 2 by being electrically connected to the circular tube spring member 25. The inner electrode lead wire 6 is led to the proximal end cap 12 as a bundle of electric wires 26 together with the above-described electric wires (not shown), and led to the outside through the round hole 12c. The inner electrode lead wire 6 is electrically connected to the arithmetic unit (not shown) described above.
[0097]
The outer electrode lead wire 7 is accommodated in the space 16 and one end thereof is electrically connected to the ring 17. The outer electrode lead wire 7 is electrically connected to the ring 17 to be electrically connected to the circular tube portion 22 and the disc portion 21, the conductive ring 23 and the outer electrode 3 of the conductive holder 27. The outer electrode lead wire 7 is led to the proximal end cap 12 as a bundle of electric wires 26 together with the above-described unillustrated electric wires and the like, and is led to the outside through the round hole 12c. The outer electrode lead wire 7 is electrically connected to the arithmetic device (not shown) described above.
[0098]
Further, an O-ring 30 made of an elastic material such as silicone rubber is provided in the base end cap 12. The O-ring 30 is formed in an annular shape. In the initial state, the O-ring 30 is formed so that the inner diameter is smaller than the outer diameter of the wire bundle 26 and the outer diameter is larger than the inner diameter of the small-diameter portion 11 a of the outer electrode holder 11.
[0099]
The O-ring 30 is arranged on the inner side of the small diameter portion 11 a of the outer electrode holder 11, that is, on the inner side of the cylindrical portion 12 b of the proximal cap 12, through the wire bundle 26. When the O-ring 30 is provided in the base end cap 12, the O-ring 30 keeps a liquid-tight space between the wire bundle 26 and the inner peripheral surface of the small diameter portion 11 a of the outer electrode holder 11.
[0100]
For example, even when the temperature of the electrolyte solution is relatively low and the condensed condensed water adheres to the vicinity of the round hole 12c of the proximal end cap 12 or the like, the condensed water enters the space 16. To prevent.
[0101]
In addition, in the state where the temperature detection unit 5 is provided in the temperature detection unit insertion hole 2d and the ring 17 and the retaining ring 19 are accommodated in the space 16, the inelastic layer 31 and the space 16 are included. The elastic layer 32 is filled and stacked.
[0102]
The inelastic layer 31 is filled in the small diameter portion 11a and on the outer periphery of the wire bundle 26. The inelastic layer 31 is disposed between the O-ring 30 and the ring 17 along the longitudinal direction of the inner and outer electrodes 2 and 3. The inelastic layer 31 is formed from a synthetic resin made of an inelastic material such as an epoxy resin that does not have elasticity.
[0103]
The elastic layer 32 is filled between the inelastic layer 31 and the ring 17 along the longitudinal direction of the electrodes 2 and 3. The elastic layer 32 is made of a synthetic resin made of an elastic material such as sponge rubber. The inelastic layer 31 and the elastic layer 32 prevent the condensed water adhering to the vicinity of the round hole 12 c or the like from entering the space 16.
[0104]
The cap nut 71 is made of a synthetic resin such as the above-described fluororesin such as PPS, PEEK, or PTFE, and integrally includes a circular disc portion 73 and a cylindrical tube portion 74. The disc part 73 is formed so that the outer diameter is larger than the outer diameters of the outer electrode holder 11 and the tube part 61c.
[0105]
The disc portion 73 is provided with a through hole 75 in the center thereof. The through hole 75 has an inner diameter that is substantially equal to the outer diameter of the small diameter portion 11 a of the outer electrode holder 11. The cylindrical portion 74 is continuous with the outer edge of the disc portion 73. A parallel screw 76 is formed on the inner peripheral surface of the cylindrical portion 74.
[0106]
The cap nut 71 is attached to the pipe portion 61c by the parallel screw 76 being screwed into the taper screw 62 in a state where the small diameter portion 11a, that is, the support portion 4 is passed through the through hole 75. At this time, the edge portion of the cylindrical portion 74 away from the disc portion 73 is located near the center of the taper screw 62 along the axial direction of the tube portion 61c. Further, the cap nut 71 surrounds the outer periphery of both the outer electrode holder 11, that is, the support portion 4 and the tube portion 61c. The cap nut 71 is attached to the tube portion 61c, thereby pressing the outer electrode holder 11, that is, the support portion 4 toward the end surface 61d of the tube portion 61c.
[0107]
The coil spring 72 has a relatively small spring constant. The coil spring 72 is made of a well-known steel such as stainless steel, and has a rectangular cross-sectional shape. When the parallel screw 76 of the cap nut 71 is screwed into the taper screw 62 of the pipe portion 61c, the coil spring 72 passes through the small diameter portion 11a inside thereof and the step surface 11f connecting the small diameter portion 11a and the large diameter portion 11b. And the disc portion 73.
[0108]
The coil spring 72 urges the outer electrode holder 11, that is, the support portion 4, toward the end surface 61d of the tube portion 61c. The coil spring 72 brings the seal protrusion 33 into intimate contact with the end surface 61d of the pipe portion 61c.
[0109]
The seal protrusion 33 protrudes from the surface 11 g of the disk portion 11 c that faces the end surface 61 d of the tube portion 61 c of the outer electrode holder 11. The surface 11g forms an end face close to the tube portion 61c of the T-shaped joint 60. The seal protrusion 33 protrudes toward the end surface 61d of the pipe portion 61c. The seal protrusion 33 extends in an annular shape coaxial with the hole 11e and the disc portion 11c.
[0110]
The seal protrusion 33 is arranged along the circumferential direction of the disc part 11c. The seal protrusion 33 is made of a synthetic resin such as a fluororesin such as PPS, PEEK, and PTFE, which is the same as the outer electrode holder 11. In the illustrated example, the seal protrusion 33 is formed integrally with the outer electrode holder 11 and has a U-shape that becomes gradually narrower as the cross-sectional shape becomes farther from the disk portion 11c.
[0111]
According to the above-described configuration, the electrode 1 of the resistivity meter has the inner and outer electrodes 2 and 3 inserted through the opening of the tube portion 61c, the parallel screw 76 is screwed into the taper screw 62, and the tube portion 61c, that is, T Attached to the tube joint 60. At least the tip portions 2g and 3c of the inner electrode 2 and the outer electrode 3 are disposed in a flow path of ultrapure water as an electrolyte solution flowing in the T-shaped pipe joint 60, respectively.
[0112]
The resistivity meter using the electrode 1 measures the resistivity of the electrolyte solution by measuring the electrical resistance between the electrodes 2 and 3 transmitted to the arithmetic unit or the like via the lead wires 6 and 7. .
[0113]
At this time, information corresponding to the temperature of the electrolyte solution is transmitted from the temperature sensing portion of the temperature sensor element to the arithmetic device via the electric wire or the like. The arithmetic unit or the like compensates the temperature of the electrolyte solution, and calculates the resistivity of the electrolyte solution at a predetermined constant temperature. Then, the arithmetic unit or the like calculates the purity of the electrolyte solution based on the resistivity.
[0114]
According to the electrode 1 of the resistivity meter of the present embodiment, the inner electrode 2 and the outer electrode 3 are provided with large-diameter members 2b and 3e and small-diameter members 2a and 3d. The large diameter members 2b and 3e are connected to the small diameter members 2a and 3d. For this reason, the large-diameter members 2b and 3e and the small-diameter members 2a and 3d can be manufactured separately, and these can be connected to manufacture the inner electrode 2 and the outer electrode 3.
[0115]
Moreover, since the large diameter members 2b and 3e and the small diameter members 2a and 3d can be manufactured separately, the depth of the hole formed in the large diameter member 2b can be particularly reduced. Furthermore, the small-diameter member 2a of the inner electrode 2 and the large-diameter member 3e of the outer electrode 3 can be formed from a tubular member. After the through hole 48 is made in the large diameter member 3e, the inner surface of the large diameter member 3e is cut. For this reason, the burr | flash produced on the edge of the through-hole 48 can be removed reliably, and the man-hour required for removing this burr | flash can be suppressed.
[0116]
Therefore, since the large diameter members 2b and 3e and the small diameter members 2a and 3d can be manufactured separately, the deterioration of the material yield of the inner and outer electrodes 2 and 3 and the time required for processing can be suppressed. Therefore, the cost increase of the inner and outer electrodes 2 and 3 can be suppressed, and the cost increase of the electrode 1 of the resistivity meter can be suppressed. The small diameter member 2a of the inner electrode 2 is made of stainless steel. For this reason, material cost can be suppressed. Therefore, it is possible to more reliably suppress the cost increase.
[0117]
Further, when the first screw threads 41, 51 and the second screw threads 42, 52 are screwed together, any one of the projections 43, 53 of the large diameter members 2b, 3e and the small diameter members 2a, 3d is moved to the other. Press fit. The protrusions 43 and 53 are difficult to insert into the other base material. For this reason, when the adhesive is applied to the first screw threads 41, 51 and the second screw threads 42, 52 to fix the large diameter members 2b, 3e and the small diameter members 2a, 3d to each other, The base material of the large-diameter members 2b and 3e and the base material of the small-diameter members 2a and 3d are reliably in contact with each other. Therefore, the large diameter members 2b and 3e and the small diameter members 2a and 3d are reliably electrically connected. Therefore, the resistivity of the electrolyte solution can be reliably measured.
[0118]
In the embodiment described above, the protrusion 43 is provided on the small diameter member 2 a of the inner electrode 2, and the protrusion 53 is provided on the large diameter member 3 e of the outer electrode 3. However, in the present invention, the protrusion 43 may be provided on the large diameter member 2 b of the inner electrode 2, and the protrusion 53 may be provided on the small diameter member 3 d of the outer electrode 3. Further, both the inner electrode 2 and the outer electrode 3 are configured by connecting small-diameter members 2a and 3d and large-diameter members 2b and 3e. However, in the present invention, at least one of the inner and outer electrodes 2 and 3 may be configured by connecting the small diameter members 2a and 3d and the large diameter members 2b and 3e.
[0119]
As shown in FIG. 8, the large-diameter member 2b and the small-diameter member 2a of the inner electrode 2 are combined with a first thread 41, a second thread 42, and a distal end portion 44 of the small-diameter member 2a as a press-fit portion. You may connect using. The first thread 41 is formed on the outer peripheral surface of the small diameter member 2a. The first thread 41 is provided at the center of the small diameter member 2a.
[0120]
The second screw thread 42 is formed on the inner peripheral surface of the large-diameter member 2b. The first thread 41 and the second thread 42 are screwed together. The distal end portion 44 is of course provided on the small diameter member 2 a and is disposed closer to the large diameter member 2 b than the first screw thread 41. The outer diameter D1 of the distal end portion 44 is slightly larger than the inner diameter d1 of the large diameter member 2b. The difference between the outer diameter D1 of the distal end portion 44 and the inner diameter d1 of the large-diameter member 2b is preferably in the range of 0.01 mm or more and 0.05 mm or less.
[0121]
In this case, when connecting the large diameter member 2b and the small diameter member 2a, the first thread 41 and the second thread 42 are screwed together. Then, since the outer diameter D1 of the distal end portion 44 is slightly larger than the inner diameter d1 of the large diameter member 2b, the distal end portion 44 is press-fitted into the large diameter member 2b. Then, the inner electrode 2 is assembled.
[0122]
Similarly to the above-described embodiment, the large diameter member 2b and the small diameter member 2a can be manufactured separately, so that the deterioration of the material yield of the inner electrode 2 and the time required for processing can be suppressed. Therefore, an increase in the cost of the inner electrode 2 can be suppressed, and an increase in the cost of the electrode 1 of the resistivity meter can be suppressed. Further, the outer diameter D1 of the distal end portion 44 is slightly larger than the inner diameter d1 of the large diameter member 2b. For this reason, the large diameter member 2b and the small diameter member 2a can be fixed without applying an adhesive to the first thread 41 and the second thread 42. Therefore, since it is not necessary to use an adhesive, the large-diameter member 2b and the small-diameter member 2a can be reliably electrically connected, and the resistivity of the electrolyte solution can be reliably measured.
[0123]
Further, as shown in FIG. 9, the large-diameter member 2b and the small-diameter member 2a of the inner electrode 2 may be connected using a convex portion 58a and a concave portion 59a with which the convex portion 58a engages. The convex portion 58a is formed to be convex from the outer peripheral surface of the tip end portion 44 of the small diameter member 2a. The recess 59a is formed in a recess from the inner peripheral surface of the large-diameter member 2b.
[0124]
In this case, it is desirable that the outer diameter D1 of the distal end portion 44 of the small diameter member 2a is slightly larger than the inner diameter d1 of the large diameter member 2b. The difference between the outer diameter D1 of the distal end portion 44 of the small diameter member 2a and the inner diameter d1 of the large diameter member 2b is preferably in the range of 0.01 mm or more and 0.03 mm or less. Further, it is desirable that the protruding amount from the outer peripheral surface of the convex portion 58a and the depth from the inner peripheral surface of the concave portion 59a are about 0.005 mm to 0.015 mm, which is half of the dimension.
[0125]
In this case, when connecting the large-diameter member 2b and the small-diameter member 2a, the distal end portion 44 of the small-diameter member 2a is inserted inside the large-diameter member 2b. Then, since the outer diameter D1 of the distal end portion 44 is slightly larger than the inner diameter d1 of the large diameter member 2b, the distal end portion 44 is press-fitted into the large diameter member 2b. And the convex part 58a engages with the recessed part 59a, and the inner electrode 2 is assembled.
[0126]
Similarly to the above-described embodiment, the large diameter member 2b and the small diameter member 2a can be manufactured separately, so that the deterioration of the material yield of the inner electrode 2 and the time required for processing can be suppressed. Therefore, an increase in the cost of the inner electrode 2 can be suppressed, and an increase in the cost of the electrode 1 of the resistivity meter can be suppressed. Further, the outer diameter D1 of the distal end portion 44 is slightly larger than the inner diameter d1 of the large-diameter member 2b, and the convex portion 58a and the concave portion 59a are engaged with each other. For this reason, the large diameter member 2b and the small diameter member 2a can be fixed without applying an adhesive. Therefore, since it is not necessary to use an adhesive, the large-diameter member 2b and the small-diameter member 2a can be reliably electrically connected, and the resistivity of the electrolyte solution can be reliably measured.
[0127]
As shown in FIG. 9, when the large diameter member 2b and the small diameter member 2a are fixed using the convex portion 58a and the concave portion 59a, the convex portion 58a is convex from the inner peripheral surface of the large diameter member 2b. Alternatively, the recess 59a may be formed as a recess from the outer peripheral surface of the small diameter member 2a.
[0128]
As shown in FIG. 10, the large-diameter member 3e and the small-diameter member 3d of the outer electrode 3 are connected to the first thread 51, the second thread 52, and the base end 55 of the large-diameter member 3e as a press-fit portion. You may connect using. The first thread 51 is formed on the outer peripheral surface of the annular portion 50b of the small diameter member 3d.
[0129]
The second screw thread 52 is formed on the inner peripheral surface of the large-diameter member 3e. The first thread 51 and the second thread 52 are screwed together. Of course, the base end portion 55 is provided on the large-diameter member 3 e and is disposed closer to the small-diameter member 3 d than the second screw thread 52. The inner diameter D2 of the base end portion 55 is slightly smaller than the outer diameter d2 of the annular portion 50b of the small diameter member 3d. The difference between the inner diameter D2 of the base end portion 55 and the outer diameter d2 of the annular portion 50b of the small diameter member 3d is preferably in the range of 0.01 mm or more and 0.05 mm or less. The outer diameter d2 of the annular portion 50b of the small diameter member 3d is the outer diameter d2 of the small diameter member 3d.
[0130]
In this case, when connecting the large diameter member 3e and the small diameter member 3d, the first thread 51 and the second thread 52 are screwed together. Then, since the inner diameter D2 of the base end portion 55 is slightly smaller than the outer diameter d2 of the annular portion 50b of the small diameter member 3d, the small diameter member 3d is press-fitted into the base end portion 55. Then, the outer electrode 3 is assembled.
[0131]
Similar to the above-described embodiment, the large-diameter member 2b and the small-diameter member 2a can be manufactured separately, so that the deterioration of the material yield of the outer electrode 3 and the time required for processing can be suppressed. Therefore, the cost increase of the outer electrode 3 can be suppressed, and the cost increase of the electrode 1 of the resistivity meter can be suppressed. Further, the inner diameter D2 of the base end portion 55 is slightly smaller than the outer diameter d2 of the annular portion 50b of the small diameter member 3d. For this reason, the large diameter member 3e and the small diameter member 3d can be fixed without applying an adhesive to the first thread 51 and the second thread 52. Therefore, since it is not necessary to use an adhesive, the large-diameter member 3e and the small-diameter member 3d can be reliably electrically connected, and the resistivity of the electrolyte solution can be reliably measured.
[0132]
Further, as shown in FIG. 11, the large-diameter member 3e and the small-diameter member 3d of the outer electrode 3 may be connected using a convex portion 58b and a concave portion 59b with which the convex portion 58b engages. The convex portion 58b is formed to be convex from the inner peripheral surface of the base end portion 55 of the large-diameter member 3e. The concave portion 59b is formed in a concave shape from the outer peripheral surface of the annular portion 50b of the small diameter member 3d.
[0133]
In this case, the inner diameter D2 of the base end portion 55 of the large diameter member 3e is preferably slightly smaller than the outer diameter d2 of the annular portion 50b of the small diameter member 3d. The difference between the inner diameter D2 of the base end portion 55 of the large-diameter member 3e and the outer diameter d2 of the annular portion 50b of the small-diameter member 3d is preferably in the range of 0.01 mm or more and 0.03 mm or less. Further, it is desirable that the protruding amount from the inner peripheral surface of the convex portion 58b and the depth from the outer peripheral surface of the concave portion 59b are about 0.005 mm to 0.015 mm, which is half of the dimension.
[0134]
In this case, when connecting the large diameter member 3e and the small diameter member 3d, the annular portion 50b of the small diameter member 3d is inserted inside the base end portion 55 of the large diameter member 3e. Then, since the inner diameter D2 of the base end portion 55 is slightly smaller than the outer diameter d2 of the annular portion 50b of the small diameter member 3d, the small diameter member 3d is press-fitted into the base end portion 55. And the convex part 58b engages with the recessed part 59b, and the outer electrode 3 is assembled.
[0135]
Similar to the above-described embodiment, the large-diameter member 3e and the small-diameter member 3d can be manufactured separately, so that the deterioration of the material yield of the outer electrode 3 and the time required for processing can be suppressed. Therefore, the cost increase of the outer electrode 3 can be suppressed, and the cost increase of the electrode 1 of the resistivity meter can be suppressed. Further, the inner diameter D2 of the base end portion 55 is slightly smaller than the outer diameter d2 of the annular portion 50b of the small diameter member 3d, and the convex portion 58b and the concave portion 59b are engaged with each other. For this reason, the large diameter member 3e and the small diameter member 3d can be fixed without applying an adhesive. Therefore, since it is not necessary to use an adhesive, the large-diameter member 3e and the small-diameter member 3d can be reliably electrically connected, and the resistivity of the electrolyte solution can be reliably measured.
[0136]
In addition, as shown in FIG. 11, when the large diameter member 3e and the small diameter member 3d are fixed using the convex portion 58b and the concave portion 59b, the convex portion 58b is the outer periphery of the annular portion 50b of the small diameter member 3d. The concave portion 59b may be formed concave from the inner peripheral surface of the base end portion 55 of the large diameter member 3e.
[0137]
Furthermore, although the embodiment described above shows a case where it is used for measuring the purity of ultrapure water as a cleaning liquid in the rinsing process, the electrode 1 of the present invention is used in a pure water production apparatus for producing ultrapure water. Can also be used. In this case, for example, the pipe portion 61a is connected to a supply source of pure water that is a raw material of ultrapure water (water that is not as much as the above-described ultrapure water but intentionally reduces impurities: also called high-purity water). ing. The pipe part 61b is connected to a pure water production apparatus.
[0138]
The electrode 1 can be attached without dust (particles) made of metal or resin entering the pipe joint 60 even when used in a pure water production apparatus. For this reason, it can suppress that the ion exchange resin and filter of a pure water manufacturing apparatus degrade, and the target pure water can be obtained rapidly. Therefore, it is possible to accurately measure the purity of the pure water, and to suppress an increase in cost for manufacturing ultrapure water.
[0139]
【The invention's effect】
As described above, according to the first aspect of the present invention, at least one electrode member includes a large-diameter member and a small-diameter member. These are connected. For this reason, a large diameter member and a small diameter member can be manufactured separately, and these can be connected, and the said electrode member can be manufactured. Since the large-diameter member and the small-diameter member can be manufactured separately, deterioration of the material yield of the electrode member can be suppressed. Therefore, an increase in the cost of the electrode member can be suppressed and an increase in the cost of the electrode of the resistivity meter can be suppressed.
[0140]
First When the first screw thread and the second screw thread are screwed together, either one of the large diameter member and the small diameter member is press-fitted into the other. Therefore, when the adhesive is applied to the large-diameter member and the small-diameter member and these members are fixed to each other, the base material of the large-diameter member and the base material of the small-diameter member are reliably in contact with each other. Therefore, the large diameter member and the small diameter member are reliably electrically connected. Therefore, the deterioration of the material yield of the electrode member can be suppressed and the increase in cost can be suppressed, and the resistivity of the electrolyte solution can be reliably measured.
[0141]
Claim 2 According to the present invention, since the press-fitting part bites into the other, an adhesive is applied to the large-diameter member and the small-diameter member, and when these members are fixed to each other, The base material of the small diameter member comes into contact with certainty. Therefore, the large diameter member and the small diameter member are reliably electrically connected. Therefore, the deterioration of the material yield of the electrode member can be suppressed and the increase in cost can be suppressed, and the resistivity of the electrolyte solution can be reliably measured.
[0142]
Claim 3 According to the present invention described above, the outer diameter of the press-fit portion arranged closer to the larger diameter member than the first screw thread is larger than the inner diameter of the large diameter member. For this reason, these members can be fixed to each other without applying an adhesive to the large diameter member and the small diameter member. Therefore, the large diameter member and the small diameter member are reliably electrically connected. Therefore, the deterioration of the material yield of the electrode member can be suppressed and the increase in cost can be suppressed, and the resistivity of the electrolyte solution can be reliably measured.
[0143]
Claim 4 According to the present invention, the inner diameter of the press-fitting portion arranged closer to the small diameter member than the second thread is smaller than the outer diameter of the small diameter member. For this reason, these members can be fixed to each other without applying an adhesive to the large diameter member and the small diameter member. Therefore, the large diameter member and the small diameter member are reliably electrically connected. Therefore, the deterioration of the material yield of the electrode member can be suppressed and the increase in cost can be suppressed, and the resistivity of the electrolyte solution can be reliably measured.
[0144]
Claim 5 According to the present invention, the convex portion that is convex from one side is engaged with the concave portion that is concave from one side among the inner peripheral surface of the large-diameter member and the outer peripheral surface of the small-diameter member. For this reason, these members can be fixed to each other without applying an adhesive to the large diameter member and the small diameter member. Therefore, the large diameter member and the small diameter member are reliably electrically connected. Therefore, the deterioration of the material yield of the electrode member can be suppressed and the increase in cost can be suppressed, and the resistivity of the electrolyte solution can be reliably measured.
[0145]
Claim 6 According to the present invention described in (1), the inner electrode includes the large-diameter member and the small-diameter member. For this reason, a large diameter member and a small diameter member can be manufactured separately, and these can be connected, and the said inner electrode can be manufactured. Since the large-diameter member and the small-diameter member can be manufactured separately, deterioration of the material yield of the inner electrode can be suppressed. Therefore, an increase in the cost of the inner electrode can be suppressed and an increase in the cost of the electrode of the resistivity meter can be suppressed.
[0146]
Claim 7 According to the present invention described above, the outer electrode includes the large-diameter member and the small-diameter member. For this reason, a large-diameter member and a small-diameter member can be manufactured separately, and these can be connected to manufacture the outer electrode. Since the large-diameter member and the small-diameter member can be manufactured separately, deterioration of the material yield of the outer electrode can be suppressed. Therefore, the increase in the cost of the outer electrode can be suppressed, and the increase in the cost of the electrode of the resistivity meter can be suppressed.
[0147]
Claim 8 According to the present invention, the inner and outer electrodes are provided with a large diameter member and a small diameter member. For this reason, a large-diameter member and a small-diameter member can be manufactured separately, and these can be connected to manufacture each of the inner and outer electrodes. Since the large-diameter member and the small-diameter member can be manufactured separately, deterioration of the material yield of the inner and outer electrodes can be suppressed. Therefore, an increase in the cost of the electrodes of the resistivity meter can be suppressed by suppressing an increase in the cost of the inner and outer electrodes.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing the overall configuration of electrodes of a resistivity meter according to an embodiment of the present invention.
FIG. 2 is an enlarged cross-sectional view showing a main part of the electrode shown in FIG.
3 is a cross-sectional view of inner and outer electrodes of the electrode shown in FIG.
4 is an enlarged cross-sectional view showing a connection portion between a large diameter member and a small diameter member of the inner electrode shown in FIG. 3;
5 is a cross-sectional view showing a process of connecting a large diameter member and a small diameter member of the inner electrode shown in FIG. 4;
6 is an enlarged cross-sectional view showing a connection portion between a large-diameter member and a small-diameter member of the outer electrode shown in FIG.
7 is a cross-sectional view showing a process of connecting a large diameter member and a small diameter member of the outer electrode shown in FIG. 6;
8 is an enlarged cross-sectional view showing a modified example of a connecting portion between a large diameter member and a small diameter member of the inner electrode shown in FIG. 4;
9 is an enlarged cross-sectional view showing another modified example of the connection portion between the large-diameter member and the small-diameter member of the inner electrode shown in FIG. 4;
10 is an enlarged cross-sectional view showing a modified example of a connecting portion between a large-diameter member and a small-diameter member of the outer electrode shown in FIG.
11 is an enlarged cross-sectional view showing another modified example of the connection portion between the large-diameter member and the small-diameter member of the outer electrode shown in FIG.
FIG. 12 is a cross-sectional view showing the overall configuration of an electrode of a conventional resistivity meter.
[Explanation of symbols]
1 Electrodes of resistivity meter
2 Inner electrode (electrode member)
2a Small diameter member
2b Large diameter member
3 Outer electrode (electrode member)
3d small diameter member
3e Large diameter member
41 First thread
42 Second thread
43 Protrusion (press-fit part)
44 Tip of small diameter member (press-fit, one end)
46, 47 faces
50b Ring (one end)
51 First thread
52 Second Thread
53 Projection (Press-fit part)
55 Base end of large diameter member (press-fit part)
56, 57 faces
58a, 58b Convex part
59a, 59b recess
D1 Outer diameter of tip
D2 Inside diameter of the base end
d1 Inner diameter of large diameter member
d2 Outer diameter of the annular part of the small diameter member (outer diameter of the small diameter member)
t Predetermined interval
