JP3850211B2

JP3850211B2 - Retaining ring

Info

Publication number: JP3850211B2
Application number: JP2000324359A
Authority: JP
Inventors: 要城下; 昇源; 俊雄飯田
Original assignee: JTEKT Corp
Current assignee: JTEKT Corp
Priority date: 2000-10-24
Filing date: 2000-10-24
Publication date: 2006-11-29
Anticipated expiration: 2020-10-24
Also published as: JP2002130234A

Description

【０００１】
【発明の属する技術分野】
本発明は、機械要素である止め輪の改良に関する。
【０００２】
【従来の技術】
図１５に示す従来のトルクセンサ１０１は、センサハウジング１０２に内蔵される筒状の一対のコイルホルダー１０３、１０４と、そのコイルホルダー１０３、１０４により保持されるコイル１０５、１０６と、そのコイル１０５、１０６により囲まれるトルク伝達シャフト１０７とを備え、そのコイル１０５、１０６の出力に基づき伝達トルクを検出する。そのシャフト１０７は軸受１０８、１０９を介してセンサハウジング１０２により支持され、一方の軸受１０８の外輪１０８ａと一方のコイルホルダー１０３との間と、両コイルホルダー１０３、１０４の間とにスペーサ１１０、１１１が介在する。そのセンサセンサハウジング１０２の内部に設けられた周溝１０２ｂに従来周知の止め輪１１０が嵌入され、その止め輪１１０に伝達シャフト１０７が挿入される。その止め輪１１０とコイルホルダー１０３、１０４との間に板バネ１１２が介在する。その止め輪１１０とセンサハウジング１０２の内部に設けられた受け部１０２ａとの間に、コイルホルダー１０３、１０４、軸受１０８の外輪１０８ａ、スペーサ１１０、１１１、板バネ１１２が挟み込まれる。この挟み込み状態において板バネ１１２が自然状態から弾性的に圧縮変形した状態とされることで、コイルホルダー１０３、１０４をスペーサ１１０、１１１と軸受１０８の外輪１０８ａを介して受け部１０２ａに向かい押し付ける弾力が付与される。これによりコイルホルダー１０３、１０４をセンサハウジング１０２に対してがたをなくして固定できる。
【０００３】
【発明が解決しようとする課題】
上記従来の構成では、コイルホルダー１０３、１０４を弾力によって受け部１０２ａに押し付けるため、止め輪１１０と板バネ１１２とが必要である。そのため、部品点数が多くなり、トルクセンサ１０１の寸法が伝達シャフト１０７の軸方向において大きくなり、組み立てにも手間を要するという問題がある。
【０００４】
本発明は上記従来技術の問題を解決することができる止め輪を提供することを目的とする。
【０００５】
【課題を解決するための手段】
本発明は、割り部を有する環状部を備え、径が拡縮するように弾性変形可能とされている止め輪に適用される。
【０００６】
本発明の第１の特徴は、その環状部の内周により片持ち状に支持されると共に、周方向に沿って並列する複数の突出部が、その環状部と一体的に成形され、各突出部は、その環状部の内周から中心に向かうに従い軸方向一方に向かうように、その環状部から径方向内方および軸方向外方に突出され、各突出部は環状部に対して軸方向において弾性的に揺動可能とされ、前記割り部に近接して配置される突出部の周方向における寸法は、前記割り部から離れて配置される突出部の周方向における寸法よりも大きくされている点にある。
本発明の第１の特徴によれば、止め輪の環状部を例えばセンサハウジング等の収容部材の内周に形成された溝に嵌入し、その収容部材に収容される被収容部材を、その止め輪の突出部と収容部材に対する軸方向変位が規制されている受け部とで挟み込み、この挟み込み状態において突出部が自然状態から弾性的に揺動した状態とされることで、その被収容部材を受け部に向かい押し付ける弾力を付与できる。すなわち、弾性部材を用いることなく止め輪だけで被収容部材をがたつきなく固定できる。また、各突出部を環状部に対して弾性的に揺動させ、被収容部材あるいは被嵌め合わせ部材を受け部に押し付ける弾力を作用させる際に、その押し付け力が割り部の近傍において割り部から離れた位置よりも小さくなるのを防止でき、その押し付け力の均一化を図ることができる。
【０００７】
特に、センサハウジングに内蔵される筒状のコイルホルダーと、そのコイルホルダーにより保持されるコイルと、そのコイルにより囲まれるトルク伝達シャフトとを備え、そのコイルの出力に基づき伝達トルクを検出するトルクセンサにおいて、そのセンサハウジングの内部に設けられた溝に本発明の第１の特徴を備えた止め輪の環状部が嵌入され、その止め輪に前記伝達シャフトが挿入され、その止め輪の突出部とセンサセンサハウジングの内部に設けられた受け部との間に前記コイルホルダーが挟み込まれ、このコイルホルダーの挟み込み状態において突出部が自然状態から弾性的に揺動した状態とされることで、そのコイルホルダーを前記受け部に向かい押し付ける弾力が付与されるのが好ましい。
【０００８】
本発明の第２の特徴は、その環状部の外周により片持ち状に支持されると共に、周方向に沿って並列する複数の突出部が、その環状部と一体的に成形され、各突出部は、その環状部の外周から放射方向に向かうに従い軸方向一方に向かうように、その環状部から径方向外方および軸方向外方に突出され、各突出部は環状部に対して軸方向において弾性的に揺動可能とされ、前記割り部に近接して配置される突出部の周方向における寸法は、前記割り部から離れて配置される突出部の周方向における寸法よりも大きくされている点にある。
本発明の第２の特徴によれば、止め輪の環状部を例えばシャフト等の軸部材の外周に形成された溝に嵌入し、その軸部材の外周に嵌め合わされる被嵌め合わせ部材を、その止め輪の突出部と軸部材に対して軸方向変位が規制されている受け部とで挟み込み、この挟み込み状態において突出部が自然状態から弾性的に揺動した状態とされることで、その被嵌め合わせ部材を受け部に向かい押し付ける弾力を付与できる。すなわち、弾性部材を用いることなく止め輪だけで被嵌め合わせ部材をがたつきなく固定できる。また、各突出部を環状部に対して弾性的に揺動させ、被収容部材あるいは被嵌め合わせ部材を受け部に押し付ける弾力を作用させる際に、その押し付け力が割り部の近傍において割り部から離れた位置よりも小さくなるのを防止でき、その押し付け力の均一化を図ることができる。
【０００９】
本発明の止め輪において、前記環状部の内外周は円周に沿うものとされ、その環状部の内周が沿う円周の中心と外周が沿う円周の中心とは互いに対して偏心し、その環状部の内周と外周との間の径方向における距離は、前記割り部に近接する程に小さくされているのが好ましい。
この構成によれば、止め輪を収容部材や軸部材に形成された溝に嵌入するため、割り部の間隔を狭めて径を縮小する際に、環状部の内周と外周との間の径方向における距離が割り部に近接する程に小さくされていることで、止め輪を容易に弾性変形させることができる。これにより、その止め輪の溝への嵌入作業を容易に行える。
【００１１】
本発明の止め輪において、各突出部は、突出方向前端部位が凸曲面となるように湾曲されているのが好ましい。
これにより、各突出部に接する部材が傷付くのを防止できる。
【００１２】
【発明の実施の形態】
図１〜図４を参照して本発明の第１実施形態を説明する。
図１に示すトルクセンサ１は、車両の電動パワーステアリング装置における操舵トルクを検出する。そのトルクセンサ１は、センサハウジング２と、入力シャフト３と、出力シャフト４とを備えている。その入力シャフト３は、そのセンサハウジング２の内周により転がり軸受１２を介して支持される。その出力シャフト４は、センサハウジング２の内周により転がり軸受１３、１４を介して支持される。その入出力シャフト３、４がトルク伝達シャフトになる。
【００１３】
その入力シャフト３の一端にステアリングシャフト６の一端がピン８により連結されている。そのステアリングシャフト６の他端はステアリングホイール（図示省略）に接続される。その入力シャフト３と出力シャフト４にトーションバー７が挿入される。そのトーションバー７は、一端が入力シャフト３の一端に上記ピン８により連結され、他端が出力シャフト４に図外ピンにより連結されている。これにより、その入力シャフト３と出力シャフト４は操舵抵抗に応じたトーションバー７の捩じれにより、弾性的に相対回転可能とされている。
【００１４】
その出力シャフト４の回転が、例えばラックピニオン式ステアリングギア等を介して車輪に伝達されることで車両の舵角が変化する。その出力シャフト４の外周にウォームホイール１５が同行回転するように取り付けられる。そのウォームホイール１５は、操舵補助力発生用モータにより回転駆動されるウォーム１６に噛み合う。
【００１５】
その出力シャフト４の外周に、磁性材製の第１筒状部材２１が同行回転するように取り付けられている。その入力シャフト３の外周に、その第１筒状部材２１の一端面に対向する一端面を有する磁性材製の第２筒状部材２２と、この第２筒状部材２１の他端面に対向する一端面を有する磁性材製の第３筒状部材２３とが、同行回転するように取り付けられている。その第１、第２筒状部材２１、２２の相対向する端面それぞれに、複数の歯２１ａ、２２ａが周方向の間隔をおいて設けられている。その第３筒状部材２３の一端面に、複数の歯２３ａが周方向の間隔をおいて設けられている。その第２筒状部材２１の他端面は歯が形成されず平坦とされている。
【００１６】
そのセンサハウジング２に、上記軸受１２、１３の間において磁性材製の筒状第１コイルホルダー３１と磁性材製の筒状第２コイルホルダー３２とが、入出力シャフト３、４の軸方向に沿って並列するように内蔵されている。その第１コイルホルダー３１により第１コイル３３が保持され、その第２コイルホルダー３２により第２コイル３４が保持されている。各コイルホルダー３１、３２は、入出力シャフト３、４と同心に配置される周壁３１ａ、３２ａと、この周壁３１ａ、３２ａの一端から径方向内方に向かい延びる円環状側壁３１ｂ、３２ｂと、その周壁３１ａ、３２ａの他端から径方向内方に向かい延びる円環状蓋部材３１ｃ、３２ｃとを有する。各コイル３３、３４は入出力シャフト３、４を囲む。
【００１７】
各コイル３３、３４は、センサハウジング２に取り付けられたプリント基板４１に配線を介して接続される。そのプリント基板４１上の図４に示す信号処理回路により、検出トルク値に対応する信号が出力される。すなわち、その第１筒状部材２１の一端部と第２筒状部材２２の一端部とは第１コイル３３により覆われ、その第２筒状部材２２の他端部と第３筒状部材２３の一端部とは第２コイル３４により覆われる。その第１筒状部材２１と第２筒状部材２２の歯２１ａ、２２ａの対向部分の面積は、入出力シャフト５により伝達されるトルクに応じてトーションバー７が捩れて両筒状部材２１、２２が相対回転することで変化する。この変化により、その歯２１ａ、２２ａの対向間において、第１コイル３３の発生磁束に対する磁気抵抗が変化する。その変化に応じて第１コイル３３の出力が変化することから、そのコイル３３の出力に基づき伝達トルクを検出できる。その第２筒状部材２２の他端と第３筒状部材２３の歯２３ａとの対向部分の面積は一定とされ、第２コイル３４の発生磁束に対する磁気抵抗の変化は操舵抵抗の影響を受けることがなく、温度変動による第１コイル３３の出力変動と第２コイル３４の出力変動とは互いに等しくされる。第１コイル３３は抵抗４５を介して発振器４６に接続され、第２コイル３４は抵抗４７を介して発振器４６に接続されている。各コイル３３、３４は差動増幅回路４８に接続され、その差動増幅回路４８の出力値がトルクセンサ１による検出トルクに対応するものとされる。これにより、温度変動によるトルクセンサ１の出力変動が補償されている。その差動増幅回路４８から出力される伝達トルクに対応した信号に応じて上記モータが駆動され、そのモータの回転がウォーム１６、ウォームホイール１５を介して出力シャフト４に伝達されることで操舵補助力が付与される。
【００１８】
その入出力シャフト３、４の軸方向において、第１コイルホルダー３１の一端はセンサハウジング２の内周に嵌め合わされた止め輪６０に当接し、第２コイルホルダー３２の一端はスペーサ５６に当接し、第１コイルホルダー３１の他端と第２コイルホルダー３２の他端とは互いに当接し、スペーサ５６は軸受１２の外輪１２ａに当接し、その外輪１２ａはセンサハウジング２の内面の段差により構成される受け部２′に当接するように配置される。その第１、第２コイルホルダー３１、３２をスペーサ５６と軸受１２の外輪１２ａとを介して受け部２′に押し付ける弾力が、その止め輪６０により付与される。
【００１９】
図２、図３に示すように、その止め輪６０は、割り部６１を有する環状部６２と複数の突出部６３とを備える。その割り部６１の間隔Ｗが変化することで、止め輪６０は径が拡縮するように弾性変形可能とされている。また、割り部６１に隣接する両突出部６３に工具挿入孔６５が形成されている。その環状部６２の内外周は円周に沿うものとされ、本実施形態では環状部６２の内周６２ａが沿う円周と外周６２ｂが沿う円周とは同一の中心Ｏを有する。各突出部６３は、環状部６２の内周により片持ち状に支持されると共に、周方向に沿って並列し、例えばバネ鋼板等から環状部６２と一体的に成形される。各突出部６３それぞれの径方向寸法は互いに等しくされ、また、各突出部６３それぞれの周方向寸法も互いに等しくされている。
【００２０】
各突出部６３は、環状部６２の内周から中心Ｏに向かうに従い軸方向一方に向かうように、その環状部６２から径方向内方および軸方向外方に突出され、環状部６２に対して軸方向において弾性的に揺動可能とされている。
【００２１】
その止め輪６０の環状部６２は上記センサハウジング２の内部に形成された周溝７１に嵌入される。すなわち、工具挿入孔６５に挿入される工具により止め輪６０は径が縮小するように弾性変形され、その状態でセンサハウジング２に挿入され、しかる後に復元変形されることで溝７１に嵌入される。本実施形態では、その溝７１は上記軸受１３の外輪１３ａの一端面と、センサハウジング２に形成された凹部の内面とにより構成されているが、環状部を嵌入できる溝であれば構成は限定されず、例えばセンサハウジング２内面に形成される凹部だけで溝を構成してもよい。その止め輪６０に上記入出力シャフト３、４が挿入される。その止め輪６０の突出部６３とセンサハウジング２の内部に設けられた受け部２′との間に上記コイルホルダー３１、３２がスペーサ５６と軸受１２の外輪１２ａと共に挟み込まれる。このコイルホルダー３１、３２の挟み込み状態において、環状部６２に対して各突出部６３が自然状態から弾性的に揺動した状態とされる。本実施形態では、軸受１３の外輪１３ａの一端面と受け部２′との間の距離が、止め輪６０、両コイルホルダー３１、３２、スペーサ５６、軸受１２の外輪１２ａの軸方向寸法の総和よりも小さくされている。これにより、両コイルホルダー３１、３２をスペーサ５６と軸受１２の外輪１２ａを介して受け部２′に向かい押し付ける弾力が付与される。
【００２２】
上記構成によれば、従来のような板バネを用いることなく止め輪６０だけで、コイルホルダー３１、３２をスペーサ５６と軸受１２の外輪１２ａと共にセンサハウジング２に対してがたつきをなくして固定することができる。
【００２３】
図５は、第１実施形態の第１変形例の止め輪１６０を示す。上記実施形態の止め輪６０との相違は、環状部６２の内周６２ａが沿う円周の中心Ｏ１と外周６２ｂが沿う円周の中心Ｏ２とが、図においてＥだけ互いに対して偏心する。これにより、その環状部６２の内周６２ａと外周６２ｂとの間の径方向における距離は、周方向において漸次変化するものとされ、その距離は割り部６１に近接する程に小さくされる。また、各突出部６３の径方向寸法が互いに異なるものとされることで、各突出部６３の先端は環状部６２の外周６２ｂが沿う円周と同心の円周上に位置される。これにより、突出部６３を溝７１に嵌入するために割り部６１の間隔Ｗを狭めて止め輪１６０の径を縮小する際に、環状部６２の内周と外周との間の径方向における距離が割り部６１に近接する程に小さくされていることで、止め輪１６０への曲げ応力を均等にでき、大きく変位させることができる。よって、その止め輪１６０の溝７１への嵌入作業を容易に行える。他は上記実施形態と同様で同様部分は同一符号で示す。
【００２４】
図６は、第１実施形態の第２変形例の止め輪２６０を示し、上記第１変形例の止め輪１６０との相違は、各突出部６３の径方向寸法が互いに等しくされることで、各突出部６３の先端は環状部６２の内周６２ａが沿う円周と同心の円周上に位置される。他は第１変形例と同様で同様部分は同一符号で示す。
【００２５】
図７は、第１実施形態の第３変形例の止め輪３６０を示す。上記実施形態の止め輪６０との相違は、各突出部６３の周方向における寸法が互いに異なるものとされ、割り部６１に近接して配置される突出部６３の周方向における寸法が、その割り部６１から離れて配置される突出部６３の周方向における寸法よりも大きくされている点にある。これにより、各突出部６３を環状部６２に対して弾性的に揺動させ、両コイルホルダー３１、３２をスペーサ５６と軸受１２の外輪１２ａと共に受け部２′に向かい押し付ける弾力を作用させる際に、その押し付け力が割り部６１の近傍においては割り部６１から離れた位置よりも小さくなるのを防止でき、その押し付け力の均一化を図ることができる。他は上記実施形態と同様で同様部分は同一符号で示す。
【００２６】
図８は、第１実施形態の第４変形例の止め輪４６０を示し、上記第３変形例の止め輪３６０との相違は、環状部６２の内周６２ａが沿う円周の中心Ｏ１と外周６２ｂが沿う円周の中心Ｏ２とが、図においてＥだけ互いに対して偏心する。これにより、その環状部６２の内周６２ａと外周６２ｂとの間の径方向における距離は、周方向において漸次変化するものとされ、その距離は割り部６１に近接する程に小さくされる。また、各突出部６３の径方向寸法が互いに異なるものとされることで、各突出部６３の先端は環状部６２の外周６２ｂが沿う円周と同心の円周上に位置される。これにより、第１、第２変形例と同様に止め輪４６０の径を容易に縮小することができる。他は第３変形例と同様で同様部分は同一符号で示す。
【００２７】
図９は、第１実施形態の第５変形例の止め輪５６０を示し、上記第４変形例の止め輪４６０との相違は、各突出部６３の径方向寸法が互いに等しくされることで、各突出部６３の先端は環状部６２の内周６２ａが沿う円周と同心の円周上に位置される。他は第４変形例と同様で同様部分は同一符号で示す。
【００２８】
上記第１実施形態と、その第１〜第５変形例においては、図１０の（１）に示すように各突出部６３は突出方向前端部位がエッジ６３ａとされているが、図１０の（２）に示すように各突出部６３は突出方向前端部位が凸曲面６３ｂとなるように湾曲されていてもよい。これにより、各突出部６３に接する第１コイルホルダー３１が傷付くのを防止できる。
【００２９】
図１１〜図１３を参照して本発明の第２実施形態を説明する。
図１１に示すように、上記第１実施形態の電動パワーステアリング装置におけるステアリングシャフト６は、車体に取り付けられるステアリングコラム８０により、転がり軸受８１を介して支持され、ステアリングホイールＨの操舵により回転する。
【００３０】
そのステアリングシャフト６の軸方向において、転がり軸受８１の内輪８１ａの一端はスペーサ８２の他端に当接し、そのスペーサ８２の一端はステアリングシャフト６の外周に嵌め合わされた止め輪９０に当接する。その転がり軸受８１の外輪８１ｂの他端は、ステアリングコラム８０の内周に形成された段差により構成される受け部８０ａに当接する。その転がり軸受８１をスペーサ８２を介して受け部８０ａに押し付ける弾力が、その止め輪９０により付与される。
【００３１】
図１２、図１３に示すように、その止め輪９０は、割り部９１を有する環状部９２と複数の突出部９３とを備える。その割り部９１の間隔Ｗが変化することで、止め輪９０は径が拡縮するように弾性変形可能とされている。また、割り部９１に隣接する両突出部９３に工具挿入孔９５が形成されている。その環状部９２の内外周は円周に沿うものとされ、本実施形態では環状部９２の内周９２ａが沿う円周と外周９２ｂが沿う円周とは同一の中心Ｏを有する。各突出部９３は、環状部９２の外周により片持ち状に支持されると共に、周方向に沿って並列し、例えばバネ鋼板等から環状部９２と一体的に成形される。各突出部９３それぞれの径方向寸法は互いに等しくされ、また、各突出部９３それぞれの周方向寸法も互いに等しくされている。
【００３２】
各突出部９３は、環状部９２の外周から放射方向に向かうに従い軸方向一方に向かうように、その環状部９２から径方向外方および軸方向外方に突出され、環状部９２に対して軸方向において弾性的に揺動可能とされている。
【００３３】
その止め輪９０の環状部９２は上記ステアリングシャフト６の外周に形成された周溝９６に嵌入される。すなわち、工具挿入孔９５に挿入される工具により止め輪９０は径が拡大するように弾性変形され、その状態でステアリングシャフト６に嵌め合わされ、しかる後に復元変形されることで溝９６に嵌入される。その止め輪９０の突出部９３と上記ステアリングコラム８０に形成された受け部８０ａとの間に上記転がり軸受８１とスペーサ８２とが挟み込まれる。この挟み込み状態において、環状部９２に対して各突出部９３が自然状態から弾性的に揺動した状態とされる。これにより、転がり軸受８１をスペーサ８２を介して受け部８０ａに向かい押し付ける弾力が付与される。そのスペーサ８２により突出部９３が転がり軸受８１の外輪８１ｂに接するのが阻止されている。
【００３４】
上記構成によれば、弾性体を用いることなく止め輪９０だけで転がり軸受８１をスペーサ８２と共にステアリングコラム８０に対してがたつきをなくして固定することができる。
【００３５】
上記第２実施形態の第１変形例として、上記第１実施形態の第１変形例と同様に、環状部９２の内周が沿う円周の中心と外周が沿う円周の中心とが互いに対して偏心し、その環状部９２の内周と外周との間の径方向における距離が周方向において漸次変化するものとされ、その距離は割り部９１に近接する程に小さくされ、また、各突出部９３の径方向寸法が互いに異なるものとされることで、各突出部９３の先端は環状部９２の外周が沿う円周と同心の円周上に位置されてもよい。これにより、突出部９３を溝９６に嵌入するために割り部９１の間隔Ｗを拡大して止め輪９０の径を拡大する際に、環状部９２の内周と外周との間の径方向における距離が割り部９１に近接する程に小さくされていることで、止め輪９０への曲げ応力を均等にでき、大きく変位させることができる。よって、その止め輪９０の溝９６への嵌入作業を容易に行える。
【００３６】
その第２実施形態の第２変形例として、上記第１実施形態の第２変形例と同様に、各突出部９３の径方向寸法が互いに等しくされ、各突出部９３の先端が環状部９２の内周が沿う円周と同心の円周上に位置される以外は第１変形例と同様の構成としてもよい。
【００３７】
上記第２実施形態の第３変形例として、上記第１実施形態の第３変形例と同様に、各突出部９３の周方向における寸法が互いに異なるものとされ、割り部９１に近接して配置される突出部９３の周方向における寸法が、その割り部９１から離れて配置される突出部９３の周方向における寸法よりも大きくされてもよい。これにより、各突出部９３を環状部９２に対して弾性的に揺動させ、転がり軸受８１をスペーサ８２と共に受け部８０ａに向かい押し付ける弾力を作用させる際に、その押し付け力が割り部９１の近傍においては割り部９１から離れた位置よりも小さくなるのを防止でき、その押し付け力の均一化を図ることができる。
【００３８】
その第２実施形態の第４変形例として、上記第１実施形態の第４変形例と同様に、環状部９２の内周が沿う円周の中心と外周が沿う円周の中心とが互いに対して偏心し、その環状部９２の内周と外周との間の径方向における距離が周方向において漸次変化するものとされ、その距離は割り部９１に近接する程に小さくされ、また、各突出部９３の径方向寸法が互いに異なるものとされることで、各突出部９３の先端は環状部９２の外周が沿う円周と同心の円周上に位置される以外は、第３変形例と同様の構成としてもよい。これにより、第１、第２変形例と同様に止め輪９０の径を容易に拡大することができる。
【００３９】
その第２実施形態の第５変形例として、上記第１実施形態の第５変形例と同様に、各突出部９３の径方向寸法が互いに等しくされることで、各突出部９３の先端は環状部９２の内周が沿う円周と同心の円周上に位置される以外は第４変形例と同様の構成としてもよい。
【００４０】
上記第２実施形態と、その第１〜第５変形例においては、図１４の（１）に示すように各突出部９３は突出方向前端部位がエッジ９３ａとされているが、図１４の（２）に示すように各突出部９３は突出方向前端部位が凸曲面９３ｂとなるように湾曲されていてもよい。これにより、各突出部９３に接するスペーサ８２が傷付くのを防止できる。
【００４１】
本発明は上記実施形態や変形例に限定されない。例えば止め輪により受け部に弾力によって押し付けられるものは、コイルホルダーやスペーサや軸受の外輪に限定されず、また、その数は単一でも複数でもよい。
【００４２】
【発明の効果】
本発明によれば、トルクセンサにおけるセンサハウジングのような収容部材に対してコイルホルダーのような被収容部材を固定したり、シャフト等の軸部材の外周に嵌め合わされる被嵌め合わせ部材を、その軸部材に対して軸方向変位が規制されている受け部に対して固定する場合に、板バネ等の弾性部材を別途用いることなく、省スペース化を図り、能率良く、均一な弾力の作用によりがたつきなく固定できる止め輪を提供できる。
【図面の簡単な説明】
【図１】本発明の第１実施形態のトルクセンサの断面図
【図２】本発明の第１実施形態の止め輪の正面図
【図３】本発明の第１実施形態の止め輪の側面図
【図４】本発明の実施形態のトルクセンサの回路構成説明図
【図５】本発明の第１実施形態の第１変形例の止め輪の正面図
【図６】本発明の第１実施形態の第２変形例の止め輪の正面図
【図７】本発明の第１実施形態の第３変形例の止め輪の正面図
【図８】本発明の第１実施形態の第４変形例の止め輪の正面図
【図９】本発明の第１実施形態の第５変形例の止め輪の正面図
【図１０】本発明の第１実施形態とその変形例の止め輪の（１）は突出部を示す部分断面図、（２）は（１）とは異なる突出部を示す部分断面図
【図１１】本発明の第２実施形態のステアリング装置の部分断面図
【図１２】本発明の第２実施形態の止め輪の正面図
【図１３】本発明の第２実施形態の止め輪の側面図
【図１４】本発明の第２実施形態とその変形例の止め輪の（１）は突出部を示す部分断面図、（２）は（１）とは異なる突出部を示す部分断面図
【図１５】従来例のトルクセンサの断面図
【符号の説明】
１トルクセンサ
３、４入出力シャフト
３１、３２コイルホルダー
３３、３４コイル
６０、９０止め輪
６１、９１割り部
６２、９２環状部
６３、９３突出部
６３ｂ、９３ｂ凸曲面
７１、９６溝[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement of a retaining ring which is a mechanical element.
[0002]
[Prior art]
A conventional torque sensor 101 shown in FIG. 15 includes a pair of cylindrical coil holders 103 and 104 built in a sensor housing 102, coils 105 and 106 held by the coil holders 103 and 104, and the coil 105, A torque transmission shaft 107 surrounded by 106, and detects the transmission torque based on the outputs of the coils 105 and 106. The shaft 107 is supported by the sensor housing 102 through bearings 108 and 109, and spacers 110 and 111 are provided between the outer ring 108a of one bearing 108 and the one coil holder 103 and between the coil holders 103 and 104. Intervenes. A conventionally known retaining ring 110 is fitted into a circumferential groove 102 b provided inside the sensor sensor housing 102, and the transmission shaft 107 is inserted into the retaining ring 110. A leaf spring 112 is interposed between the retaining ring 110 and the coil holders 103 and 104. Coil holders 103 and 104, outer ring 108 a of bearing 108, spacers 110 and 111, and leaf spring 112 are sandwiched between retaining ring 110 and receiving portion 102 a provided inside sensor housing 102. In this sandwiched state, the leaf spring 112 is elastically compressed and deformed from the natural state, so that the coil holders 103 and 104 are elastically pressed against the receiving portion 102a through the spacers 110 and 111 and the outer ring 108a of the bearing 108. Is granted. As a result, the coil holders 103 and 104 can be fixed to the sensor housing 102 without rattling.
[0003]
[Problems to be solved by the invention]
In the above conventional configuration, the retaining ring 110 and the leaf spring 112 are required to press the coil holders 103 and 104 against the receiving portion 102a with elasticity. Therefore, the number of parts increases, the dimension of the torque sensor 101 becomes large in the axial direction of the transmission shaft 107, and there is a problem that assembly is also troublesome.
[0004]
An object of the present invention is to provide a retaining ring that can solve the above-described problems of the prior art.
[0005]
[Means for Solving the Problems]
The present invention is applied to a retaining ring that includes an annular portion having a split portion and is elastically deformable so as to expand and contract in diameter.
[0006]
The first feature of the present invention is that it is supported in a cantilevered manner by the inner periphery of the annular portion, and a plurality of protrusions arranged in parallel along the circumferential direction are formed integrally with the annular portion, and each protrusion The part protrudes radially inward and axially outward from the annular part so as to go in one axial direction as it goes from the inner periphery to the center of the annular part, and each protruding part is axially directed to the annular part. Can be rocked elasticallyThe dimension in the circumferential direction of the projecting part arranged close to the split part is made larger than the dimension in the circumferential direction of the projecting part arranged away from the split part.There is in point.
According to the first aspect of the present invention, the annular portion of the retaining ring is fitted into a groove formed on the inner periphery of the accommodating member such as the sensor housing, and the member to be accommodated accommodated in the accommodating member is By sandwiching between the projecting portion of the ring and the receiving portion in which axial displacement with respect to the housing member is regulated, the projecting portion is elastically swung from the natural state in this sandwiched state, so that the member to be accommodated is Elasticity that pushes against the receiving part can be given. That is, the member to be accommodated can be fixed without rattling with only a retaining ring without using an elastic member.Further, when each projecting portion is elastically swung with respect to the annular portion and an elastic force pressing the receiving member or the fitted member against the receiving portion is applied, the pressing force is applied from the split portion in the vicinity of the split portion. It can be prevented from becoming smaller than a distant position, and the pressing force can be made uniform.
[0007]
In particular, a torque sensor that includes a cylindrical coil holder built in the sensor housing, a coil held by the coil holder, and a torque transmission shaft surrounded by the coil, and detects transmission torque based on the output of the coil In the above, the annular portion of the retaining ring having the first feature of the present invention is inserted into the groove provided in the sensor housing, the transmission shaft is inserted into the retaining ring, and the protruding portion of the retaining ring The coil holder is sandwiched between a receiving portion provided inside the sensor sensor housing, and the projecting portion is elastically swung from the natural state when the coil holder is sandwiched, so that the coil It is preferable that the elasticity which presses a holder toward the said receiving part is provided.
[0008]
The second feature of the present invention is that it is supported in a cantilevered manner by the outer periphery of the annular portion, and a plurality of protrusions arranged in parallel along the circumferential direction are formed integrally with the annular portion, and each protrusion Is protruded radially outward and axially outward from the annular portion so as to go in one axial direction as it goes in the radial direction from the outer periphery of the annular portion, and each protruding portion in the axial direction with respect to the annular portion Elastically swingableThe dimension in the circumferential direction of the projecting part arranged close to the split part is made larger than the dimension in the circumferential direction of the projecting part arranged away from the split part.There is in point.
According to the second feature of the present invention, the annular member of the retaining ring is fitted into a groove formed on the outer periphery of a shaft member such as a shaft, for example, and the fitted member fitted on the outer periphery of the shaft member is When the protruding portion of the retaining ring and the receiving portion whose axial displacement is restricted with respect to the shaft member are sandwiched, the protruding portion is elastically swung from the natural state in this sandwiched state. The elasticity which presses a fitting member toward a receiving part can be provided. That is, it is possible to fix the fitted member without rattling with only a retaining ring without using an elastic member.Further, when each projecting portion is elastically swung with respect to the annular portion and an elastic force pressing the receiving member or the fitted member against the receiving portion is applied, the pressing force is applied from the split portion in the vicinity of the split portion. It can be prevented from becoming smaller than a distant position, and the pressing force can be made uniform.
[0009]
In the retaining ring of the present invention, the inner and outer circumferences of the annular part are along the circumference, and the center of the circumference along the inner circumference of the annular part and the center of the circumference along the outer circumference are eccentric with respect to each other, The distance in the radial direction between the inner periphery and the outer periphery of the annular portion is preferably made smaller as it approaches the split portion.
According to this configuration, when the retaining ring is inserted into the groove formed in the housing member or the shaft member, the diameter between the inner periphery and the outer periphery of the annular portion is reduced when the interval between the split portions is reduced to reduce the diameter. The retaining ring can be easily elastically deformed by making the distance in the direction smaller as it approaches the split part. Thereby, the fitting operation | work to the groove | channel of the retaining ring can be performed easily.
[0011]
In the retaining ring of the present invention, it is preferable that each protrusion is curved so that the front end portion in the protrusion direction is a convex curved surface.
Thereby, it can prevent that the member which touches each protrusion part is damaged.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
A first embodiment of the present invention will be described with reference to FIGS.
A torque sensor 1 shown in FIG. 1 detects a steering torque in an electric power steering device for a vehicle. The torque sensor 1 includes a sensor housing 2, an input shaft 3, and an output shaft 4. The input shaft 3 is supported via a rolling bearing 12 by the inner periphery of the sensor housing 2. The output shaft 4 is supported by the inner periphery of the sensor housing 2 via rolling bearings 13 and 14. The input / output shafts 3 and 4 serve as torque transmission shafts.
[0013]
One end of the steering shaft 6 is connected to one end of the input shaft 3 by a pin 8. The other end of the steering shaft 6 is connected to a steering wheel (not shown). A torsion bar 7 is inserted into the input shaft 3 and the output shaft 4. One end of the torsion bar 7 is connected to one end of the input shaft 3 by the pin 8, and the other end is connected to the output shaft 4 by an unillustrated pin. Thereby, the input shaft 3 and the output shaft 4 are elastically rotatable relative to each other by the torsion of the torsion bar 7 corresponding to the steering resistance.
[0014]
The rotation angle of the output shaft 4 is transmitted to the wheels via, for example, a rack and pinion type steering gear, so that the steering angle of the vehicle changes. A worm wheel 15 is attached to the outer periphery of the output shaft 4 so as to rotate together. The worm wheel 15 meshes with a worm 16 that is rotationally driven by a steering assist force generating motor.
[0015]
A first cylindrical member 21 made of a magnetic material is attached to the outer periphery of the output shaft 4 so as to rotate together. On the outer periphery of the input shaft 3, the second cylindrical member 22 made of a magnetic material having one end surface facing the one end surface of the first cylindrical member 21, and the other end surface of the second cylindrical member 21. A third cylindrical member 23 made of a magnetic material having one end face is attached so as to rotate together. A plurality of teeth 21a and 22a are provided on the opposing end surfaces of the first and second cylindrical members 21 and 22 with a circumferential interval therebetween. A plurality of teeth 23 a are provided on one end face of the third cylindrical member 23 at intervals in the circumferential direction. The other end surface of the second cylindrical member 21 is flat without teeth.
[0016]
A cylindrical first coil holder 31 made of a magnetic material and a cylindrical second coil holder 32 made of a magnetic material are arranged in the sensor housing 2 between the bearings 12 and 13 in the axial direction of the input / output shafts 3 and 4. Built in to be parallel along. The first coil 33 is held by the first coil holder 31, and the second coil 34 is held by the second coil holder 32. Each of the coil holders 31 and 32 includes peripheral walls 31a and 32a arranged concentrically with the input / output shafts 3 and 4, annular side walls 31b and 32b extending radially inward from one end of the peripheral walls 31a and 32a, And annular lid members 31c and 32c extending radially inward from the other ends of the peripheral walls 31a and 32a. Each coil 33, 34 surrounds the input / output shafts 3, 4.
[0017]
Each of the coils 33 and 34 is connected to a printed circuit board 41 attached to the sensor housing 2 via wiring. The signal processing circuit shown in FIG. 4 on the printed circuit board 41 outputs a signal corresponding to the detected torque value. That is, one end of the first cylindrical member 21 and one end of the second cylindrical member 22 are covered by the first coil 33, and the other end of the second cylindrical member 22 and the third cylindrical member 23. Is covered with a second coil 34. The areas of the opposing portions of the teeth 21a, 22a of the first cylindrical member 21 and the second cylindrical member 22 are such that the torsion bar 7 is twisted according to the torque transmitted by the input / output shaft 5, and both the cylindrical members 21, It changes by the relative rotation of 22. Due to this change, the magnetic resistance to the magnetic flux generated by the first coil 33 changes between the teeth 21a and 22a facing each other. Since the output of the first coil 33 changes according to the change, the transmission torque can be detected based on the output of the coil 33. The area of the facing portion between the other end of the second cylindrical member 22 and the tooth 23a of the third cylindrical member 23 is constant, and the change in the magnetic resistance with respect to the magnetic flux generated by the second coil 34 is affected by the steering resistance. In other words, the output fluctuation of the first coil 33 and the output fluctuation of the second coil 34 due to temperature fluctuation are equal to each other. The first coil 33 is connected to the oscillator 46 via a resistor 45, and the second coil 34 is connected to the oscillator 46 via a resistor 47. Each of the coils 33 and 34 is connected to a differential amplifier circuit 48, and the output value of the differential amplifier circuit 48 corresponds to the torque detected by the torque sensor 1. Thereby, the output fluctuation of the torque sensor 1 due to the temperature fluctuation is compensated. The motor is driven in accordance with a signal corresponding to the transmission torque output from the differential amplifier circuit 48, and the rotation of the motor is transmitted to the output shaft 4 via the worm 16 and the worm wheel 15, thereby assisting steering. Power is granted.
[0018]
In the axial direction of the input / output shafts 3 and 4, one end of the first coil holder 31 abuts on a retaining ring 60 fitted to the inner periphery of the sensor housing 2, and one end of the second coil holder 32 abuts on the spacer 56. The other end of the first coil holder 31 and the other end of the second coil holder 32 are in contact with each other, the spacer 56 is in contact with the outer ring 12a of the bearing 12, and the outer ring 12a is constituted by a step on the inner surface of the sensor housing 2. It arrange | positions so that it may contact | abut to the receiving part 2 '. The retaining ring 60 imparts elasticity that presses the first and second coil holders 31 and 32 against the receiving portion 2 ′ via the spacer 56 and the outer ring 12 a of the bearing 12.
[0019]
As shown in FIGS. 2 and 3, the retaining ring 60 includes an annular portion 62 having a split portion 61 and a plurality of protruding portions 63. By changing the interval W between the split portions 61, the retaining ring 60 can be elastically deformed so that its diameter expands and contracts. In addition, tool insertion holes 65 are formed in both projecting portions 63 adjacent to the split portion 61. The inner and outer circumferences of the annular portion 62 are along the circumference, and in this embodiment, the circumference along the inner circumference 62a of the annular portion 62 and the circumference along the outer circumference 62b have the same center O. Each projecting portion 63 is supported in a cantilevered manner by the inner periphery of the annular portion 62 and is arranged in parallel along the circumferential direction, and is integrally formed with the annular portion 62 from, for example, a spring steel plate or the like. The radial dimensions of the protrusions 63 are equal to each other, and the circumferential dimensions of the protrusions 63 are also equal to each other.
[0020]
Each protrusion 63 protrudes radially inward and outward in the axial direction from the inner periphery of the annular portion 62 so as to go to one side in the axial direction from the inner periphery toward the center O. It can be elastically swung in the axial direction.
[0021]
The annular portion 62 of the retaining ring 60 is fitted into a circumferential groove 71 formed inside the sensor housing 2. That is, the retaining ring 60 is elastically deformed so that the diameter is reduced by the tool inserted into the tool insertion hole 65, and is inserted into the sensor housing 2 in that state, and then is restored and deformed to be fitted into the groove 71. . In the present embodiment, the groove 71 is configured by one end surface of the outer ring 13a of the bearing 13 and the inner surface of the recess formed in the sensor housing 2, but the configuration is limited as long as the annular portion can be fitted therein. For example, the groove may be formed only by the recess formed in the inner surface of the sensor housing 2. The input / output shafts 3 and 4 are inserted into the retaining ring 60. The coil holders 31 and 32 are sandwiched together with the spacer 56 and the outer ring 12 a of the bearing 12 between the protruding portion 63 of the retaining ring 60 and the receiving portion 2 ′ provided inside the sensor housing 2. In a state where the coil holders 31 and 32 are sandwiched, the protrusions 63 are elastically swung from the natural state with respect to the annular portion 62. In this embodiment, the distance between one end surface of the outer ring 13a of the bearing 13 and the receiving portion 2 'is the sum of the axial dimensions of the retaining ring 60, the coil holders 31, 32, the spacer 56, and the outer ring 12a of the bearing 12. Has been smaller than. Thereby, the elasticity which presses both the coil holders 31 and 32 toward the receiving part 2 'via the spacer 56 and the outer ring | wheel 12a of the bearing 12 is provided.
[0022]
According to the above configuration, the coil holders 31 and 32 are fixed to the sensor housing 2 together with the spacer 56 and the outer ring 12a of the bearing 12 by using only the retaining ring 60 without using a leaf spring as in the prior art. can do.
[0023]
FIG. 5 shows a retaining ring 160 of a first modification of the first embodiment. The difference from the retaining ring 60 of the above embodiment is that the center O1 of the circumference along the inner periphery 62a of the annular portion 62 and the center O2 of the circumference along the outer periphery 62b are eccentric from each other by E in the drawing. Thereby, the distance in the radial direction between the inner periphery 62 a and the outer periphery 62 b of the annular portion 62 is assumed to gradually change in the circumferential direction, and the distance is reduced as the distance from the split portion 61 becomes closer. Further, since the radial dimensions of the protrusions 63 are different from each other, the tips of the protrusions 63 are positioned on a circumference that is concentric with the circumference along the outer periphery 62b of the annular part 62. As a result, the radial distance between the inner periphery and the outer periphery of the annular portion 62 when the interval W of the split portion 61 is reduced to reduce the diameter of the retaining ring 160 in order to fit the protruding portion 63 into the groove 71. Is made so small that it approaches the split part 61, the bending stress to the retaining ring 160 can be made uniform and can be displaced greatly. Therefore, the operation of fitting the retaining ring 160 into the groove 71 can be easily performed. Others are the same as those in the above embodiment, and the same parts are denoted by the same reference numerals.
[0024]
FIG. 6 shows a retaining ring 260 of the second modification of the first embodiment. The difference from the retaining ring 160 of the first modification is that the radial dimensions of the protrusions 63 are equal to each other. The tip of each protrusion 63 is located on a circumference that is concentric with the circumference along the inner circumference 62 a of the annular part 62. Others are the same as those of the first modification, and the same parts are denoted by the same reference numerals.
[0025]
FIG. 7 shows a retaining ring 360 of a third modification of the first embodiment. The difference from the retaining ring 60 of the above embodiment is that the dimensions of the protrusions 63 in the circumferential direction are different from each other, and the dimensions of the protrusions 63 arranged in the vicinity of the split part 61 are different in the circumferential direction. This is because the size of the protruding portion 63 arranged away from the portion 61 is larger than the size in the circumferential direction. Thereby, each projecting portion 63 is elastically swung with respect to the annular portion 62, and an elastic force is applied to press both the coil holders 31, 32 toward the receiving portion 2 'together with the spacer 56 and the outer ring 12a of the bearing 12. In the vicinity of the split portion 61, the pressing force can be prevented from becoming smaller than the position away from the split portion 61, and the pressing force can be made uniform. Others are the same as those in the above embodiment, and the same parts are denoted by the same reference numerals.
[0026]
FIG. 8 shows a retaining ring 460 of a fourth modification of the first embodiment. The difference from the retaining ring 360 of the third modification is that the center O1 and the outer periphery of the circumference along the inner periphery 62a of the annular portion 62 are shown. The center O2 of the circumference along which 62b extends is eccentric with respect to each other by E in the figure. Thereby, the distance in the radial direction between the inner periphery 62 a and the outer periphery 62 b of the annular portion 62 is assumed to gradually change in the circumferential direction, and the distance is reduced as the distance from the split portion 61 becomes closer. Further, since the radial dimensions of the protrusions 63 are different from each other, the tips of the protrusions 63 are positioned on a circumference that is concentric with the circumference along the outer circumference 62b of the annular part 62. Thereby, the diameter of the retaining ring 460 can be easily reduced similarly to the first and second modified examples. Others are the same as those of the third modification, and the same parts are denoted by the same reference numerals.
[0027]
FIG. 9 shows a retaining ring 560 of a fifth modified example of the first embodiment. The difference from the retaining ring 460 of the fourth modified example is that the radial dimensions of the protruding portions 63 are equal to each other. The tip of each protrusion 63 is located on a circumference that is concentric with the circumference along the inner circumference 62 a of the annular part 62. Others are the same as those of the fourth modification, and the same parts are denoted by the same reference numerals.
[0028]
In the first embodiment and the first to fifth modifications thereof, as shown in (1) of FIG. 10, each protrusion 63 has an edge 63a at the front end portion in the protrusion direction. As shown in 2), each protrusion 63 may be curved such that the front end portion in the protrusion direction is a convex curved surface 63b. Thereby, it can prevent that the 1st coil holder 31 which contact | connects each protrusion part 63 is damaged.
[0029]
A second embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 11, the steering shaft 6 in the electric power steering apparatus of the first embodiment is supported by a steering column 80 attached to the vehicle body via a rolling bearing 81 and is rotated by steering of the steering wheel H.
[0030]
In the axial direction of the steering shaft 6, one end of the inner ring 81 a of the rolling bearing 81 abuts on the other end of the spacer 82, and one end of the spacer 82 abuts on a retaining ring 90 fitted on the outer periphery of the steering shaft 6. The other end of the outer ring 81 b of the rolling bearing 81 abuts on a receiving portion 80 a configured by a step formed on the inner periphery of the steering column 80. Elasticity that presses the rolling bearing 81 against the receiving portion 80a via the spacer 82 is applied by the retaining ring 90.
[0031]
As shown in FIGS. 12 and 13, the retaining ring 90 includes an annular portion 92 having a split portion 91 and a plurality of protruding portions 93. By changing the interval W between the split portions 91, the retaining ring 90 can be elastically deformed so that its diameter is expanded and contracted. Further, tool insertion holes 95 are formed in both protruding portions 93 adjacent to the split portion 91. The inner and outer circumferences of the annular portion 92 are along the circumference. In this embodiment, the circumference along the inner circumference 92a of the annular portion 92 and the circumference along the outer circumference 92b have the same center O. Each projecting portion 93 is supported in a cantilevered manner by the outer periphery of the annular portion 92 and is arranged in parallel along the circumferential direction, and is integrally formed with the annular portion 92 from, for example, a spring steel plate or the like. The radial dimensions of the protrusions 93 are equal to each other, and the circumferential dimensions of the protrusions 93 are also equal to each other.
[0032]
Each protruding portion 93 protrudes radially outward and axially outward from the annular portion 92 so as to go in one axial direction as it goes radially from the outer periphery of the annular portion 92, and It can be elastically swung in the direction.
[0033]
An annular portion 92 of the retaining ring 90 is fitted into a circumferential groove 96 formed on the outer periphery of the steering shaft 6. That is, the retaining ring 90 is elastically deformed so as to increase in diameter by a tool inserted into the tool insertion hole 95, and is fitted into the steering shaft 6 in that state, and then is restored and deformed to be fitted into the groove 96. . The rolling bearing 81 and the spacer 82 are sandwiched between the protruding portion 93 of the retaining ring 90 and the receiving portion 80 a formed on the steering column 80. In this sandwiched state, the protrusions 93 are elastically swung from the natural state with respect to the annular portion 92. Thereby, the elasticity which presses the rolling bearing 81 toward the receiving part 80a via the spacer 82 is provided. The protrusions 93 are prevented from contacting the outer ring 81 b of the rolling bearing 81 by the spacer 82.
[0034]
According to the above-described configuration, the rolling bearing 81 can be fixed to the steering column 80 together with the spacers 82 by using only the retaining ring 90 without using an elastic body.
[0035]
As a first modification of the second embodiment, similar to the first modification of the first embodiment, the center of the circumference along the inner circumference of the annular portion 92 and the center of the circumference along the outer circumference are in relation to each other. The distance in the radial direction between the inner periphery and the outer periphery of the annular portion 92 is gradually changed in the circumferential direction, and the distance is reduced as the distance from the split portion 91 is increased. Since the radial dimensions of the portions 93 are different from each other, the tips of the protrusions 93 may be positioned on a circumference that is concentric with the circumference along the outer circumference of the annular portion 92. As a result, when the interval W of the split portion 91 is increased to increase the diameter of the retaining ring 90 in order to fit the protruding portion 93 into the groove 96, the radial direction between the inner periphery and the outer periphery of the annular portion 92 is increased. By making the distance closer to the split portion 91, the bending stress on the retaining ring 90 can be made uniform and can be displaced greatly. Therefore, the work of fitting the retaining ring 90 into the groove 96 can be easily performed.
[0036]
As a second modification of the second embodiment, as in the second modification of the first embodiment, the radial dimensions of the protrusions 93 are equal to each other, and the tips of the protrusions 93 are the ends of the annular part 92. It is good also as a structure similar to a 1st modification except being located on the circumference concentric with the circumference which an inner periphery follows.
[0037]
As a third modification of the second embodiment, similar to the third modification of the first embodiment, the dimensions of the protrusions 93 in the circumferential direction are different from each other, and are arranged close to the split part 91. The dimension of the protruding part 93 in the circumferential direction may be larger than the dimension of the protruding part 93 arranged away from the split part 91 in the circumferential direction. As a result, each projecting portion 93 is elastically swung with respect to the annular portion 92, and when the elastic force pressing the rolling bearing 81 toward the receiving portion 80 a together with the spacer 82 is applied, the pressing force is in the vicinity of the split portion 91. Can be prevented from becoming smaller than the position away from the split portion 91, and the pressing force can be made uniform.
[0038]
As a fourth modification of the second embodiment, as in the fourth modification of the first embodiment, the center of the circumference along the inner circumference of the annular portion 92 and the center of the circumference along the outer circumference are in relation to each other. The distance in the radial direction between the inner periphery and the outer periphery of the annular portion 92 is gradually changed in the circumferential direction, and the distance is reduced as the distance from the split portion 91 is increased. Since the radial dimensions of the portions 93 are different from each other, the tip of each protruding portion 93 is positioned on a circumference that is concentric with the circumference along the outer circumference of the annular portion 92. A similar configuration may be used. Thereby, the diameter of the retaining ring 90 can be easily expanded similarly to the 1st, 2nd modification.
[0039]
As a fifth modification of the second embodiment, as in the fifth modification of the first embodiment, the radial dimensions of the protrusions 93 are equal to each other, so that the tips of the protrusions 93 are annular. The configuration may be the same as that of the fourth modified example, except that it is positioned on a circumference concentric with the circumference along which the inner circumference of the portion 92 extends.
[0040]
In the second embodiment and the first to fifth modifications thereof, as shown in FIG. 14 (1), each protrusion 93 has an edge 93a at the front end portion in the protrusion direction. As shown in 2), each protrusion 93 may be curved such that the front end portion in the protrusion direction is a convex curved surface 93b. Thereby, it can prevent that the spacer 82 which contact | connects each protrusion part 93 is damaged.
[0041]
The present invention is not limited to the above embodiments and modifications. For example, what is pressed against the receiving portion by a retaining ring by means of elasticity is not limited to the outer ring of the coil holder, spacer, or bearing, and the number thereof may be single or plural.
[0042]
【The invention's effect】
According to the present invention, a member to be accommodated such as a coil holder is fixed to an accommodation member such as a sensor housing in a torque sensor, or a fitting member to be fitted to the outer periphery of a shaft member such as a shaft is provided. When fixing to a receiving part in which axial displacement is restricted with respect to the shaft member, space saving is achieved without using an elastic member such as a leaf spring, and the operation of the elastic force is efficient and uniform. A retaining ring that can be fixed without rattling can be provided.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a torque sensor according to a first embodiment of the present invention.
FIG. 2 is a front view of a retaining ring according to the first embodiment of the present invention.
FIG. 3 is a side view of a retaining ring according to the first embodiment of the present invention.
FIG. 4 is an explanatory diagram of a circuit configuration of a torque sensor according to an embodiment of the present invention.
FIG. 5 is a front view of a retaining ring according to a first modification of the first embodiment of the present invention.
FIG. 6 is a front view of a retaining ring according to a second modification of the first embodiment of the present invention.
FIG. 7 is a front view of a retaining ring according to a third modification of the first embodiment of the present invention.
FIG. 8 is a front view of a retaining ring according to a fourth modification of the first embodiment of the present invention.
FIG. 9 is a front view of a retaining ring according to a fifth modification of the first embodiment of the present invention.
FIG. 10 is a partial cross-sectional view showing a projecting portion (1) of the retaining ring of the first embodiment of the present invention and its modification, and (2) is a partial cross-sectional view showing a projecting portion different from (1).
FIG. 11 is a partial sectional view of a steering device according to a second embodiment of the present invention.
FIG. 12 is a front view of a retaining ring according to a second embodiment of the present invention.
FIG. 13 is a side view of a retaining ring according to a second embodiment of the present invention.
FIG. 14 is a partial cross-sectional view showing a projecting portion (1) of a retaining ring according to a second embodiment of the present invention and its modification, and (2) is a partial cross-sectional view showing a projecting portion different from (1).
FIG. 15 is a sectional view of a conventional torque sensor.
[Explanation of symbols]
1 Torque sensor
3, 4 I / O shaft
31, 32 Coil holder
33, 34 coils
60, 90 retaining ring
61, 91
62, 92 Annular part
63, 93 Projection
63b, 93b Convex curved surface
71, 96 groove

Claims

In a retaining ring provided with an annular portion having a split portion and elastically deformable so that the diameter expands and contracts,
A plurality of protrusions that are supported in a cantilevered manner by the inner periphery of the annular portion, and are formed integrally with the annular portion, along the circumferential direction,
Each protruding portion protrudes radially inward and axially outward from the annular portion so as to go in one axial direction as it goes from the inner periphery to the center of the annular portion,
Each projecting portion is elastically swingable in the axial direction with respect to the annular portion ,
A retaining ring characterized in that a dimension in a circumferential direction of a projecting part arranged close to the split part is made larger than a dimension in a circumferential direction of a projecting part arranged away from the split part .

A cylindrical coil holder built into the housing;
A coil held by the coil holder;
A torque transmission shaft surrounded by the coil,
In the torque sensor that detects the transmission torque based on the output of the coil,
An annular portion of the retaining ring according to claim 1 is inserted into a groove provided in the housing, and the transmission shaft is inserted into the retaining ring,
The coil holder is sandwiched between a protruding portion of the retaining ring and a receiving portion provided inside the housing, and the protruding portion is elastically swung from a natural state when the coil holder is sandwiched. Thus, a retaining ring for the torque sensor is provided, which is provided with an elastic force that presses the coil holder toward the receiving portion.

In a retaining ring provided with an annular portion having a split portion and elastically deformable so that the diameter expands and contracts,
A plurality of protrusions that are supported in a cantilevered manner by the outer periphery of the annular portion, and are formed integrally with the annular portion, along the circumferential direction,
Each protruding portion protrudes radially outward and axially outward from the annular portion so as to go to one axial direction as it goes radially from the outer periphery of the annular portion,
Each projecting portion is elastically swingable in the axial direction with respect to the annular portion ,
A retaining ring characterized in that a dimension in a circumferential direction of a projecting part arranged close to the split part is made larger than a dimension in a circumferential direction of a projecting part arranged away from the split part .

The inner and outer circumferences of the annular portion are along the circumference,
The center of the circumference along which the inner circumference of the annular part and the center of the circumference along the outer circumference are eccentric with respect to each other,
The retaining ring according to any one of claims 1 to 3, wherein a distance in a radial direction between an inner periphery and an outer periphery of the annular portion is reduced to be closer to the split portion.

The retaining ring according to any one of claims 1 to 4, wherein each projecting portion is curved so that a front end portion in the projecting direction is a convex curved surface .