JP4356381B2

JP4356381B2 - Manufacturing method of wheel bearing unit

Info

Publication number: JP4356381B2
Application number: JP2003206446A
Authority: JP
Inventors: 博英石田
Original assignee: NSK Ltd
Current assignee: NSK Ltd
Priority date: 2003-08-07
Filing date: 2003-08-07
Publication date: 2009-11-04
Anticipated expiration: 2023-08-07
Also published as: JP2005053272A

Description

【０００１】
【発明の属する技術分野】
この発明は、自動車の車輪並びにロータ或はドラム等の制動用回転体を支持する為の車輪用軸受ユニットの製造方法の改良に関する。
【０００２】
【従来の技術】
自動車の車輪を構成するホイール１、及び、制動用回転体であって制動装置であるディスクブレーキを構成するロータ２は、例えば図２に示す様な構造により、懸架装置を構成するナックル３に回転自在に支持している。即ち、このナックル３に形成した円形の支持孔４部分に、車輪用軸受ユニット５を構成する外輪６を、複数本のボルト７により固定している。一方、この車輪用軸受ユニット５を構成するハブ８に上記ホイール１及びロータ２を、複数本のスタッド９とナット１０とにより結合固定している。
【０００３】
上記外輪６の内周面には複列の外輪軌道１１ａ、１１ｂを、外周面には結合フランジ１２を、それぞれ形成している。この様な外輪６は、この結合フランジ１２を上記ナックル３に、上記各ボルト７で結合する事により、このナックル３に対し固定している。これに対して、上記ハブ８の外周面の一部で、上記外輪６の外端開口（軸方向に関して「外」とは、自動車への組み付け状態で車両の幅方向外側となる、図１〜４の左側を言う。反対に、自動車への組み付け状態で車両の幅方向中央側となる、図１〜４の右側を「内」と言う。本明細書全体で同じ。）から突出した部分には、取付フランジ１３を形成している。上記ホイール１及びロータ２はこの取付フランジ１３の側面（図示の例では外側面１４）に、上記各スタッド９とナット１０とにより、結合固定している。
【０００４】
又、上記ハブ８の中間部外周面で、上記複列の外輪軌道１１ａ、１１ｂのうちの外側の外輪軌道１１ａに対向する部分には、第一の内輪軌道１５を形成している。更に、上記ハブ８の内端部に形成した小径段部１６に、内輪１７を外嵌固定している。そして、この内輪１７の外周面に形成した第二の内輪軌道１８を、上記複列の外輪軌道１１ａ、１１ｂのうちの内側の外輪軌道１１ｂに対向させている。又、これら各外輪軌道１１ａ、１１ｂと第一、第二の内輪軌道１５、１８との間には、それぞれが転動体である玉１９、１９を複数個ずつ、それぞれ保持器２０、２０により保持した状態で転動自在に設けている。又、上記外輪６の両端部内周面と、上記ハブ８の中間部外周面及び上記内輪１７の内端部外周面との間には、それぞれシールリング２１ａ、２１ｂを設けて、上記各玉１９、１９を設けた空間と外部空間とを遮断している。
【０００５】
更に、図示の例は、駆動輪（ＦＦ車の前輪、ＦＲ車及びＲＲ車の後輪、４ＷＤ車の全輪）用の車輪用軸受ユニット５である為、上記ハブ８の中心部に、スプライン孔２２を形成している。そして、このスプライン孔２２に、等速ジョイント２３のスプライン軸２４を挿入している。又、この状態で、この等速ジョイント２３のハウジング部２５により、上記内輪１７の内端面を抑え付けている。この様に構成する車輪支持部分の使用時には、前記ロータ２と、前記ナックル３に固定した図示しないサポート及びキャリパとを組み合わせて、制動用のディスクブレーキを構成する。制動時には、上記ロータ２を挟んで設けた１対のパッドを、このロータ２の両側面に押し付ける。
【０００６】
次に、図３〜４は、車輪用軸受ユニットの従来構造の第２〜３例を示している。これら第２〜３例の車輪用軸受ユニットは、従動輪（ＦＦ車の後輪、ＦＲ車及びＲＲ車の前輪）を支持する為に使用するものである。この為、ハブ８ａ、８ｂの中心部には、スプライン軸を挿入する為のスプライン孔を設けていない。又、図３に示した従来構造の第２例の場合には、ハブ８ａの内端部に螺合・緊締したナット２６により、このハブ８ａの小径段部１６に外嵌した内輪１７の内端面を抑え付けている。又、図４に示した従来構造の第３例の場合には、ハブ８ｂの内端部に設けた円筒部２７を径方向外方に塑性変形させて成るかしめ部２８により、このハブ８ｂの小径段部１６に外嵌した内輪１７の内端面を抑え付けている。その他の部分の構造及び作用は、上述の図２に示した従来構造の第１例の場合と同様である。
【０００７】
ところで、自動車の制動時にはしばしば、ジャダーと呼ばれる、不快な騒音を伴う振動が発生する事が知られている。この様な振動の原因としては、ロータやドラム等の制動用回転体を構成する制動用摩擦面と、パッドやシューを構成するライニングの表面との摩擦状態の不均一等、各種の原因が知られているが、上記制動用回転体の振れも、大きな原因となる事が知られている。即ち、この制動用回転体を構成する制動用摩擦面は、本来、この制動用回転体の回転中心に対して、直角（この制動用回転体がロータである場合）又は平行（この制動用回転体がドラムである場合）となるべきものである。ところが、不可避な製造誤差等により、完全に直角又は平行にする事は難しい。この為、自動車の走行時に上記制動用摩擦面は、多少とは言え、この制動用摩擦面に対し直角方向に振れる事が避けられない。この様な振れが大きくなると、制動の為に上記ライニングの表面を上記制動用摩擦面に押し付けた場合に、上記ジャダーが発生する。従って、この様なジャダーの発生を抑える為には、上記制動用摩擦面の振れを抑える事が重要となる。
【０００８】
この様な事情に鑑みて、特許文献１には、上記制動用摩擦面の振れを抑える事を目的とした発明が記載されている。この特許文献１に記載された発明を実施する場合には、先ず、上記取付フランジの側面に最終的な加工を施す前に、車輪用軸受ユニットを組み立てる。そして、この車輪用軸受ユニットの外輪を固定した状態で、ハブを回転させつつ、上記取付フランジの側面に旋削加工等を施す。これにより、この側面を所定の形状及び寸法に仕上げる。この様にして取付フランジの側面を加工すれば、加工時のハブの回転中心を、使用時のハブの回転中心に一致させる事ができる。従って、使用時のハブの回転中心に対する上記取付フランジの側面の直角度を良好にする事ができる。この結果、この取付フランジの側面に結合支持する制動用回転体の一部に設けた制動用摩擦面の振れを抑える事ができる。
【０００９】
【特許文献１】
米国特許出願公開第２００２／００６６１８５号明細書
【００１０】
【発明が解決しようとする課題】
ところが、上述の特許文献１に記載された発明の場合には、車輪用軸受ユニットを組み立てた状態で取付フランジの側面を加工する為、加工に伴って生じた切粉（金属粉末）が周囲に飛散し、上記車輪用軸受ユニットに降り掛る可能性がある。そして、降り掛った場合には、上記切粉が転動体設置部に設けたシールリングと相手面との摺接部に噛み込まれてこのシールリングを損傷させたり、或は上記切粉が転動体設置部に侵入して転動体の表面や軌道を傷付ける可能性がある為、好ましくない。そこで、この様な不都合を防止すべく、上記取付フランジの側面の加工後、上記摺接部や上記転動体設置部に侵入した切粉を除去する事が考えられる。ところが、上記取付フランジの側面の加工後の状態、即ち、上記車輪用軸受ユニットが既に組み立てられている状態では、上記摺接部や上記転動体設置部を洗浄する事ができない為、これら摺接部や転動体設置部に侵入した切粉を除去する事はできない。
【００１１】
これに対し、上記車輪用軸受ユニットを組み立てる以前に、上記取付フランジの側面を、上記ハブを単体で回転させつつ加工すれば、上述した様な不都合が生じる事はない。但し、この様にハブを単体で回転させつつ取付フランジの側面を加工する場合には、使用時のハブの回転中心に対する上記取付フランジの側面の直角度を良好にできる様にすべく、加工時のハブの回転中心を、使用時のハブの回転中心に一致させる必要がある。ところが、上記ハブを単に回転させるだけでは、加工時のハブの回転中心を、使用時のハブの回転中心に一致させる事が難しい。この為、上述の様にハブを単体で回転させつつ取付フランジの側面を加工する場合に、加工時のハブの回転中心を、使用時のハブの回転中心に一致させる為の配慮が必要になる。
本発明の車輪用軸受ユニットの製造方法は、この様な事情に鑑みて発明したものである。
【００１２】
【課題を解決するための手段】
本発明の車輪用軸受ユニットの製造方法の対象となる車輪用軸受ユニットは、前述した従来の車輪用軸受ユニットと同様に、内周面に複列の外輪軌道を有する外輪と、外周面の中間部に第一の内輪軌道を直接形成すると共に内端部に小径段部を形成したハブと、この小径段部に外嵌固定された、外周面に第二の内輪軌道を有する内輪と、上記各外輪軌道と上記第一、第二の内輪軌道との間にそれぞれ複数個ずつ転動自在に設けられた転動体とを備える。
そして、上記ハブの外周面の外端寄り部分に、使用状態でその側面に制動用回転体及び車輪を結合固定する取付フランジを設けている。
特に、本発明の製造方法の対象となる車輪用軸受ユニットに於いては、上記取付フランジの側面は、上記ハブと上記外輪と上記内輪と上記各転動体とを互いに組み立てる以前に、上記ハブを上記第一の内輪軌道と上記小径段部との互いの中心部同士を結ぶ直線を中心に回転させつつ、所定の形状に加工したものである。
【００１３】
又、本発明の車輪用軸受ユニットの製造方法は何れも、上述の様な車輪用軸受ユニットの製造方法であって、上記ハブと上記外輪と上記内輪と上記各転動体とを互いに組み立てる以前に、このハブを上記第一の内輪軌道と上記小径段部との互いの中心部同士を結ぶ直線を中心に回転させつつ、上記取付フランジの側面を所定の形状に加工する。
この為に、請求項１に記載した車輪用軸受ユニットの製造方法の場合には、上記小径段部に加工作業用内輪を外嵌すると共に、上記第一の内輪軌道、及びこの加工作業用内輪の外周面に設けた上記小径段部と同心の加工作業用内輪軌道と、変位を阻止した状態に支持した加工作業用外輪の内周面に設けた複列の加工作業用外輪軌道との間に、それぞれ複数個ずつの加工作業用転動体を転動自在に設けた状態で、上記ハブを上記加工作業用内輪と共に回転させつつ、上記取付フランジの側面を所定の形状に加工する。その後、上記ハブを、上記加工作業用内輪と上記加工作業用外輪と上記加工作業用転動体とから取り外す。次いで、上記ハブの表面を洗浄して、この表面に付着した上記取付フランジの加工に伴って生じた切粉を除去する。
又、請求項２に記載した車輪用軸受ユニットの製造方法の場合には、上記小径段部に加工作業用内輪を外嵌すると共に、上記第一の内輪軌道、及びこの加工作業用内輪の外周面に設けた上記小径段部と同心の加工作業用内輪軌道と、変位を阻止した状態に支持した加工作業用外輪の内周面に設けた複列の加工作業用外輪軌道との間に、それぞれ複数個ずつの加工作業用転動体を転動自在に設けた状態で、上記ハブを上記加工作業用内輪と共に回転させつつ、このハブ及びこの加工作業用内輪の外周面と上記加工作業用外輪の内周面との間に設けられた、上記複数個の加工作業用転動体を設置した空間内に、上記加工作業用外輪又は上記加工作業用内輪の内部に設けた圧縮空気通路を通じて圧縮空気を送り込む事により、この圧縮空気を上記空間の端部開口を通じて外部に噴出させながら、上記取付フランジの側面の加工を行なう。
【００１４】
【作用】
上述した様な本発明の車輪用軸受ユニットの製造方法によれば、使用時のハブの回転中心に対する取付フランジの側面の直角度を良好にする事ができる。即ち、使用時にハブ及び内輪は、外輪により、複数個の転動体を介して第一、第二の内輪軌道を支持された状態で回転する。言い換えれば、使用時にハブ及び内輪は、これら第一、第二の内輪軌道の互いの中心部同士を結ぶ直線を中心に回転する。又、内輪の外周面に設けた第二の内輪軌道は、この内輪を外嵌する部分である、ハブの小径段部と同心である。従って、ハブのみに着目すると、使用時にこのハブは、第一の内輪軌道と小径段部との互いの中心部同士を結ぶ直線を中心に回転する。これに対し、本発明の場合には、ハブを第一の内輪軌道と小径段部との互いの中心部同士を結ぶ直線を中心に回転させつつ、取付フランジの側面を所定の形状に加工する為、加工時のハブの回転中心を、使用時のハブの回転中心に一致させる事ができる。従って、本発明の場合には、使用時のハブの回転中心に対する取付フランジの側面の直角度を良好にする事ができる。又、本発明の場合には、取付フランジの側面の加工を、ハブを単体で回転させつつ行なうので、加工に伴って生じた切粉（金属粉末）がこのハブの表面に付着した場合でも、請求項１に係る発明の様に、加工後にこの表面を洗浄すれば、この表面から上記切粉を除去する事ができる。又、請求項２に係る発明によれば、加工に伴って生じた切粉が、外部から加工作業用転動体を設置した空間内に侵入する事を防止する事ができる。
【００１５】
【発明の実施の形態】
図１は、請求項１〜２に対応する、本発明の実施の形態の１例を示している。尚、本例の特徴は、ハブ８ｃを構成する取付フランジ１３の外側面１４の加工の仕方を工夫した点にある。このハブ８ｃを含んで構成する車輪用軸受ユニットの全体構造等、その他の部分の構造及び作用は、前述の図２に示した従来構造の第１例と同様であるから、重複する図示並びに説明は省略若しくは簡略にし、以下、本例の特徴部分を中心に説明する。
【００１６】
本例の場合には、車輪用軸受ユニットを構成する、上記ハブ８ｃと外輪６と内輪１７と複数個の玉１９、１９（図２参照）とを互いに組み立てる以前に、上記取付フランジ１３の外側面１４の最終的な加工を行なう。又、本例の場合には、この様な加工を行なうのに先立って、第一の内輪軌道１５及び小径段部１６の基端側部分（図１の左側部分）を含む、上記ハブ８ｃの中間部外周面で、図１の上半部に斜格子で示した部分に、全周に亙り高周波焼き入れ処理を施している。
【００１７】
又、本例の場合には、上記取付フランジ１３の外側面１４の加工を行なう際に、加工作業用外輪２９と、加工作業用内輪３０と、複数個の加工作業用転動体３１、３１と、１対の加工作業用保持器３２、３２とを利用する。このうちの加工作業用外輪２９は、内周面に複列の加工作業用外輪軌道３３ａ、３３ｂを、外周面に結合フランジ３４を、それぞれ設けると共に、この加工作業用外輪２９の内部に圧縮空気通路３５を、この加工作業用外輪２９の内外両周面の軸方向中間部同士を互いに連通する状態で設けている。そして、この圧縮空気通路３５の上流端（図１の上端）に、圧縮空気供給管３６の下流端を接続している。これにより、この圧縮空気供給管３６から上記圧縮空気通路３５内に圧縮空気を供給自在とし、且つ、この圧縮空気通路３５内に供給した圧縮空気を、上記加工作業用外輪２９の径方向内方に送り込み自在としている。この様な加工作業用外輪２９は、上記結合フランジ３４を工作機械を構成するハウジング３７に、複数本のボルト３８で結合する事により、このハウジング３７に対し固定している。
【００１８】
又、上記各加工作業用転動体３１、３１はそれぞれ、対象となる車輪用軸受ユニットの転動体と同様、玉である。これら各加工作業用転動体３１、３１はそれぞれ、上記各加工作業用外輪軌道３３ａ、３３ｂの内径側に複数個ずつ、上記各加工作業用保持器３２、３２により転動自在に保持した状態で配置している。これら各加工作業用保持器３２、３２はそれぞれ、合成樹脂により全体を円環状に構成している。そして、軸方向片側面に複数のポケット３９、３９を、それぞれ円周方向に関して等間隔に設けている。そして、これら各ポケット３９、３９の内側に、上記各加工作業用転動体３１、３１を、それぞれ転動自在に、且つ、これら各ポケット３９、３９からの脱落を阻止した状態で保持している。
【００１９】
又、上記加工作業用内輪３０は、全体を円筒状に構成しており、先端部（図１の左端部）外周面に加工作業用内輪軌道４０を設けている。そして、この加工作業用内輪軌道４０を設けた先端部を、前記ハブ８ｃの小径段部１６にがたつきなく外嵌自在とし、且つ、外嵌した状態で上記加工作業用内輪軌道４０が上記小径段部１６と同心になる様に、各部の寸法を規制している。この様な加工作業用内輪３０は、図１に示す様に、その先端部を軸方向内側（図１の右側）の加工作業用外輪軌道３３ｂの内径側に配置する事により、この軸方向内側の加工作業用外輪軌道３３ｂと上記加工作業用内輪軌道４０との間で、上記複数個の加工作業用転動体３１、３１を挟持している。又、この状態で、上記加工作業用外輪２９の内端部内周面と上記加工作業用内輪３０の中間部外周面との間を、シールリング４１により密閉している。又、この状態で、上記加工作業用内輪３０は、上記加工作業用外輪２９に対して回転自在である。
【００２０】
上述の様な各部材２９〜３２を利用して、上記ハブ８ｃを構成する取付フランジ１３の外側面１４を加工する場合には、図１に示す様に、上記各部材２９〜３２の内径側に上記ハブ８ｃの内半部を、軸方向外側（図１の左側）から挿入する。これにより、上記ハブ８ｃの小径段部１６に上記加工作業用内輪３０の先端部をがたつきなく外嵌すると共に、上記ハブ８ｃの第一の内輪軌道１５と軸方向外側の加工作業用外輪軌道３３ａとの間で、上記複数個の加工作業用転動体３１、３１を挟持する。又、上記ハブ８ｃの中心部に設けたスプライン孔２２に、駆動軸４２の先端部に設けた雄スプライン部４３をスプライン係合させると共に、この駆動軸４２の先端寄り部外周面に設けた外向フランジ状の押圧部４４により、上記ハブ８ｃの外端面を押圧する。これにより、上記加工作業用内輪３０の先端面を、上記ハブ８ｃの小径段部１６の基端部に存在する段差面４５に確実に当接させて、複列に設けた上記各加工作業用転動体３１、３１に、それぞれ適正な予圧を付与する。そして、この様に予圧を付与する事に基づき、次述するハブ８ｃ及び加工作業用内輪３０の回転時に、これら各部材８ｃ、３０の回転中心がふらつかない様にする。
【００２１】
上述の様にハブ８ｃをセットしたならば、次いで、上記駆動軸４２により、上記ハブ８ｃ及び加工作業用内輪３０を、上記加工作業用外輪２９に対して一体的に回転させる。これと共に、この加工作業用外輪２９の内部に設けた圧縮空気通路３５から、この加工作業用外輪２９の内周面と上記ハブ８ｃ及び加工作業用内輪３０の外周面との間に存在する上記複数個の加工作業用転動体３１、３１を設置した空間４６内に圧縮空気を送り込み、更にこの圧縮空気を、この空間４６の外端側の開口部を通じて外部空間に排出する。そして、この状態で、上記ハブ８ｃを構成する取付フランジ１３の外側面１４に、精密加工バイト４７、４７により旋削加工を施し、この外側面１４を所定の形状及び寸法に仕上げる。
【００２２】
上述の様にして取付フランジ１３の外側面１４を加工する本例の場合、車輪用軸受ユニットの使用時のハブ８ｃの回転中心に対する、上記取付フランジ１３の外側面１４の直角度を良好にする事ができる。即ち、車輪用軸受ユニットの使用時に、この車輪用軸受ユニットを構成するハブ８ｃ及び内輪１７は、外輪６により、複数個の玉１９、１９を介して第一、第二の内輪軌道１５、１８を支持された状態で回転する（図２参照）。言い換えれば、使用時に上記ハブ８ｃ及び内輪１７は、これら第一、第二の内輪軌道１５、１８の互いの中心部同士を結ぶ直線を中心に回転する。又、上記内輪１７の外周面に設けた第二の内輪軌道１８は、この内輪１７を外嵌する部分である、上記ハブ８ｃの小径段部１６と同心である。従って、上記ハブ８ｃのみに着目すると、使用時にこのハブ８ｃは、上記第一の内輪軌道１５と上記小径段部１６との互いの中心部同士を結ぶ直線を中心に回転する。
【００２３】
これに対し、上述した本例の場合、上記取付フランジ１３の外側面１４の旋削加工時に、上記ハブ８ｃ及び加工作業用内輪３０は、加工作業用外輪２９により、複数個の加工作業用転動体３１、３１を介して第一の内輪軌道１５及び加工作業用内輪軌道４０を支持された状態で回転する。言い換えれば、加工時に上記ハブ８ｃ及び加工作業用内輪３０は、これら第一の内輪軌道１５と加工作業用内輪軌道４０との互いの中心軸同士を結ぶ直線を中心に回転する。又、このうちの加工作業用内輪軌道４０は、上記ハブ８ｃの小径段部１６と同心である。従って、上記ハブ８ｃのみに着目すると、加工時にこのハブ８ｃは、上述した使用時の場合と同様、上記第一の内輪軌道１５と上記小径段部１６との互いの中心部同士を結ぶ直線を中心に回転する。この為、本例の場合には、使用時のハブ８ｃの回転中心に対する上記取付フランジ１３の外側面１４の直角度を良好にする事ができる。この結果、この取付フランジ１３の外側面１４に結合支持するロータ等の制動用回転体の一部に設けた制動用摩擦面の振れを抑えて、制動時に発生する不快な騒音や振動を抑制できる。
【００２４】
又、本例の場合には、上記加工時に、上記各加工作業用転動体３１、３１を設置した空間４６の内端開口部を、シールリング４１により塞いでいる。これと共に、前記圧縮空気通路３５から上記空間４６内に送り込んだ圧縮空気を、この空間４６の外端開口部を通じて外部に排出する事により、外部からこの外端開口部への異物の侵入を防止している。従って、本例の場合、加工に伴って生じた切粉（金属粉末）が、外部から上記空間４６内に侵入する事を防止できる。又、本例の場合、上記加工は、上記車輪用軸受ユニットを組み立てる以前に、上記ハブ８ｃのみを回転させつつ行なう。この為、加工に伴って生じた切粉（金属粉末）がこのハブ８ｃの表面に付着した場合でも、加工後にこの表面を洗浄すれば、この表面から上記切粉を除去する事ができる。従って、本例の場合、この切粉によって、車輪用軸受ユニットを構成する各シールリング２１ａ、２１ｂや、複数個の玉１９、１９の表面及び各軌道１１ａ、１１ｂ、１５、１８等が傷付く事を防止できる。
【００２５】
尚、上述した１例の場合には、圧縮空気通路を加工作業用外輪の内部に設けたが、この圧縮空気通路は、加工作業用外輪の代わりに、加工作業用内輪の内部に設ける事もできる。
【００２６】
尚、上述した実施の形態の１例では、本発明を駆動輪用の車輪用軸受ユニットに適用した例に就いて説明した。但し、本発明は、例えば前述の図３〜４に示した様な従動輪用の車輪用軸受ユニットにも適用可能である。
【００２７】
【発明の効果】
本発明の車輪用軸受ユニットの製造方法は、以上に述べた様に構成され作用するので、使用時のハブの回転中心に対する取付フランジの側面の直角度を良好にできる。この結果、この取付フランジの側面に結合支持する制動用回転体の一部に設けた制動用摩擦面の振れを抑えて、制動時に発生する不快な騒音や振動を抑制できる。又、取付フランジの側面の加工に伴って生じた切粉によりシールリング、転動体の表面、及び軌道等が傷付く事を防止できる為、品質の良好な車輪用軸受ユニットを造る事ができる。
【図面の簡単な説明】
【図１】本発明の実施の形態の１例を示す断面図。
【図２】従来構造の第１例を、自動車に組み付けた状態で示す断面図。
【図３】同第２例を示す断面図。
【図４】同第３例を示す断面図。
【符号の説明】
１ホイール
２ロータ
３ナックル
４支持孔
５車輪用軸受ユニット
６外輪
７ボルト
８、８ａ、８ｂ、８ｃハブ
９スタッド
１０ナット
１１ａ、１１ｂ外輪軌道
１２結合フランジ
１３取付フランジ
１４外側面
１５第一の内輪軌道
１６小径段部
１７内輪
１８第二の内輪軌道
１９玉
２０保持器
２１ａ、２１ｂシールリング
２２スプライン孔
２３等速ジョイント
２４スプライン軸
２５ハウジング部
２６ナット
２７円筒部
２８かしめ部
２９加工作業用外輪
３０加工作業用内輪
３１加工作業用転動体
３２加工作業用保持器
３３ａ、３３ｂ加工作業用外輪軌道
３４結合フランジ
３５圧縮空気通路
３６圧縮空気供給管
３７ハウジング
３８ボルト
３９ポケット
４０加工作業用内輪軌道
４１シールリング
４２駆動軸
４３雄スプライン部
４４押圧部
４５段差面
４６空間
４７精密加工バイト [0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement in a manufacturing method of a wheel bearing unit for supporting a vehicle wheel and a braking rotator such as a rotor or a drum.
[0002]
[Prior art]
A wheel 1 constituting a wheel of an automobile and a rotor 2 constituting a disc brake serving as a braking device and a braking device rotate to a knuckle 3 constituting a suspension device by a structure as shown in FIG. Supports freely. That is, the outer ring 6 constituting the wheel bearing unit 5 is fixed to the circular support hole 4 formed in the knuckle 3 by a plurality of bolts 7. On the other hand, the wheel 1 and the rotor 2 are coupled and fixed to a hub 8 constituting the wheel bearing unit 5 by a plurality of studs 9 and nuts 10.
[0003]
Double row outer ring raceways 11a and 11b are formed on the inner peripheral surface of the outer ring 6, and a coupling flange 12 is formed on the outer peripheral surface. Such an outer ring 6 is fixed to the knuckle 3 by connecting the connecting flange 12 to the knuckle 3 with the bolts 7. On the other hand, in a part of the outer peripheral surface of the hub 8, the outer end opening of the outer ring 6 ("outside" with respect to the axial direction is the outer side in the width direction of the vehicle when assembled to the automobile, 1-4 , on the contrary, the right side of FIGS. 1 to 4 which is the center side in the width direction of the vehicle in the assembled state in the car is called “inside”. Forms a mounting flange 13. The wheel 1 and the rotor 2 are coupled and fixed to the side surface (the outer side surface 14 in the illustrated example) of the mounting flange 13 by the studs 9 and the nuts 10.
[0004]
A first inner ring raceway 15 is formed on the outer peripheral surface of the intermediate portion of the hub 8 at a portion of the double row outer ring raceways 11a and 11b that faces the outer outer raceway 11a. Further, an inner ring 17 is externally fitted and fixed to a small diameter step portion 16 formed at the inner end portion of the hub 8. The second inner ring raceway 18 formed on the outer peripheral surface of the inner ring 17 is opposed to the inner outer ring raceway 11b of the double row outer ring raceways 11a and 11b. In addition, a plurality of balls 19, 19 each of which is a rolling element are held between the outer ring raceways 11a, 11b and the first and second inner ring raceways 15, 18 by retainers 20, 20, respectively. It is provided so that it can roll freely. Seal rings 21a and 21b are provided between the inner peripheral surface of both ends of the outer ring 6, the outer peripheral surface of the intermediate portion of the hub 8, and the outer peripheral surface of the inner end of the inner ring 17, respectively. , 19 is blocked from the external space.
[0005]
Further, since the illustrated example is a wheel bearing unit 5 for driving wheels (front wheels of FF vehicles, rear wheels of FR vehicles and RR vehicles, all wheels of 4WD vehicles), a spline is provided at the center of the hub 8. A hole 22 is formed. The spline shaft 24 of the constant velocity joint 23 is inserted into the spline hole 22. In this state, the inner end face of the inner ring 17 is held down by the housing portion 25 of the constant velocity joint 23. When the wheel support portion configured in this way is used, a brake disc brake is configured by combining the rotor 2 and a support and a caliper (not shown) fixed to the knuckle 3. During braking, a pair of pads provided across the rotor 2 are pressed against both side surfaces of the rotor 2.
[0006]
Next, FIGS. 3 to 4 show second to third examples of a conventional structure of a wheel bearing unit. These wheel bearing units of the second to third examples are used to support driven wheels (rear wheels of FF vehicles, FR vehicles, and front wheels of RR vehicles). For this reason, the spline hole for inserting a spline shaft is not provided in the center part of hub 8a, 8b. Further, in the case of the second example of the conventional structure shown in FIG. 3 , an inner ring 17 fitted on the small-diameter step portion 16 of the hub 8a is fastened by a nut 26 screwed and tightened to the inner end portion of the hub 8a. The end face is held down. In the case of the third example of the conventional structure shown in FIG. 4 , a caulking portion 28 formed by plastically deforming the cylindrical portion 27 provided at the inner end portion of the hub 8b radially outwardly is used for the hub 8b. The inner end surface of the inner ring 17 fitted on the small diameter step portion 16 is held down. The construction and function of the other parts are the same as those of the first example of the conventional structure shown in FIG. 2 described above.
[0007]
By the way, it is known that vibration accompanied by unpleasant noise, which is called judder, often occurs during braking of an automobile. The causes of such vibrations are known to be due to various causes such as non-uniform friction between the braking friction surface constituting the rotor for braking such as the rotor and drum and the surface of the lining constituting the pad and shoe. However, it is known that the vibration of the rotating body for braking is also a major cause. That is, the braking friction surface constituting the braking rotator is essentially perpendicular to the rotation center of the braking rotator (when the braking rotator is a rotor) or parallel (this braking rotator). If the body is a drum). However, it is difficult to make it completely perpendicular or parallel due to inevitable manufacturing errors. For this reason, it is inevitable that the braking friction surface swings in a direction perpendicular to the braking friction surface when the vehicle is running. When such a vibration becomes large, the judder is generated when the surface of the lining is pressed against the braking friction surface for braking. Therefore, in order to suppress the occurrence of such judder, it is important to suppress the vibration of the braking friction surface.
[0008]
In view of such circumstances, Patent Document 1 describes an invention for the purpose of suppressing the vibration of the braking friction surface. In carrying out the invention described in Patent Document 1, first, the wheel bearing unit is assembled before final processing is performed on the side surface of the mounting flange. Then, while the outer ring of the wheel bearing unit is fixed, turning or the like is performed on the side surface of the mounting flange while rotating the hub. This finishes this side surface to a predetermined shape and size. If the side surface of the mounting flange is machined in this way, the center of rotation of the hub at the time of machining can be matched with the center of rotation of the hub at the time of use. Therefore, the squareness of the side surface of the mounting flange with respect to the center of rotation of the hub in use can be improved. As a result, it is possible to suppress the vibration of the braking friction surface provided on a part of the braking rotator coupled and supported on the side surface of the mounting flange.
[0009]
[Patent Document 1]
US Patent Application Publication No. 2002/0066185
[Problems to be solved by the invention]
However, in the case of the invention described in Patent Document 1 described above, the side surface of the mounting flange is processed in a state in which the wheel bearing unit is assembled. There is a possibility of flying and falling on the wheel bearing unit. When the snow falls, the chips are caught in the sliding contact portion between the seal ring provided on the rolling element installation portion and the mating surface to damage the seal ring, or the chips are rolled. This is not preferable because it may enter the moving body installation portion and damage the surface and track of the rolling element. Therefore, in order to prevent such an inconvenience, it is conceivable to remove chips that have entered the sliding contact portion or the rolling element installation portion after processing the side surface of the mounting flange. However, in the state after processing of the side surface of the mounting flange, that is, in the state where the wheel bearing unit is already assembled, the sliding contact portion and the rolling element installation portion cannot be cleaned. It is not possible to remove the chips that have entered the part and the rolling element installation part.
[0011]
On the other hand, if the side surface of the mounting flange is processed while rotating the hub alone before assembling the wheel bearing unit, the above-described disadvantages do not occur. However, when machining the side surface of the mounting flange while rotating the hub alone as described above, the right angle of the side surface of the mounting flange with respect to the center of rotation of the hub during use should be improved. It is necessary to make the rotation center of the hub coincide with the rotation center of the hub in use. However, simply rotating the hub makes it difficult to match the center of rotation of the hub during processing to the center of rotation of the hub during use. For this reason, when processing the side surface of the mounting flange while rotating the hub alone as described above, consideration must be given to align the center of rotation of the hub during processing with the center of rotation of the hub during use. .
The manufacturing method of the wheel bearing unit of the present invention was invented in view of such circumstances.
[0012]
[Means for Solving the Problems]
The wheel bearing unit which is the object of the method for manufacturing the wheel bearing unit of the present invention is similar to the conventional wheel bearing unit described above, and an outer ring having a double row outer ring raceway on the inner peripheral surface and an intermediate between the outer peripheral surface. A hub in which a first inner ring raceway is directly formed in a portion and a small diameter step portion is formed in an inner end portion; an inner ring having a second inner ring raceway on an outer peripheral surface, which is externally fitted and fixed to the small diameter step portion; A plurality of rolling elements are provided between each outer ring raceway and the first and second inner ring raceways.
And the mounting flange which couple | bonds and fixes the rotating body for a brake and a wheel on the side surface in the state of use is provided in the part near the outer end of the outer peripheral surface of the hub.
In particular, in the wheel bearing unit that is the subject of the manufacturing method of the present invention, the side surface of the mounting flange has the hub mounted before the hub, the outer ring, the inner ring, and the rolling elements are assembled to each other. The first inner ring raceway and the small-diameter stepped portion are processed into a predetermined shape while rotating around a straight line connecting the center portions of the first inner ring raceway and the small-diameter stepped portion.
[0013]
The wheel bearing unit manufacturing method according to the present invention is a method for manufacturing a wheel bearing unit as described above, and before the hub, the outer ring, the inner ring, and the rolling elements are assembled to each other. The side surface of the mounting flange is processed into a predetermined shape while rotating the hub around a straight line connecting the center portions of the first inner ring raceway and the small diameter stepped portion.
For this reason, in the method for manufacturing a wheel bearing unit according to claim 1, the machining inner ring is fitted on the small diameter step portion, the first inner ring raceway, and the machining inner ring. Between the inner ring raceway for machining work concentric with the small-diameter step provided on the outer peripheral surface of the outer ring and the double-row outer ring raceway for machining work provided on the inner peripheral surface of the outer ring for machining operation supported in a state where displacement is prevented. In addition, the side surface of the mounting flange is machined into a predetermined shape while rotating the hub together with the inner ring for machining work in a state where a plurality of rolling elements for machining work are provided so as to roll . Thereafter, the hub is removed from the machining work inner ring, the machining work outer ring, and the machining work rolling element. Next, the surface of the hub is washed to remove chips generated due to the processing of the mounting flange attached to the surface.
In the method of manufacturing the wheel bearing unit according to claim 2, the inner ring for machining work is fitted on the small diameter step portion, and the outer circumference of the first inner ring raceway and the inner ring for machining work are Between the inner ring raceway for machining work concentric with the small-diameter step provided on the surface and the outer ring raceway for double row machining work provided on the inner peripheral surface of the outer ring for machining work supported in a state of preventing displacement, The hub, the outer peripheral surface of the inner ring for machining work, and the outer ring for machining work are rotated while the hub is rotated together with the inner ring for machining work in a state where a plurality of rolling elements for machining work are provided so as to freely roll. Compressed air through a compressed air passage provided in the outer ring for processing work or the inner ring for processing work in a space provided with the plurality of rolling elements for processing work provided between This compressed air is While is ejected to the outside through an end opening, for machining of the side surface of the mounting flange.
[0014]
[Action]
According to the method for manufacturing a wheel bearing unit of the present invention as described above, the perpendicularity of the side surface of the mounting flange with respect to the center of rotation of the hub in use can be improved. That is, in use, the hub and the inner ring rotate while the first and second inner ring raceways are supported by the outer ring via a plurality of rolling elements. In other words, in use, the hub and the inner ring rotate around a straight line connecting the center portions of the first and second inner ring raceways. Further, the second inner ring raceway provided on the outer peripheral surface of the inner ring is concentric with the small-diameter step portion of the hub, which is a part for fitting the inner ring. Therefore, when attention is paid only to the hub, the hub rotates around a straight line connecting the center portions of the first inner ring raceway and the small diameter step portion in use. On the other hand, in the case of the present invention, the side surface of the mounting flange is processed into a predetermined shape while rotating the hub around a straight line connecting the center portions of the first inner ring raceway and the small diameter stepped portion. Therefore, the center of rotation of the hub at the time of processing can be matched with the center of rotation of the hub at the time of use. Therefore, in the case of the present invention, the perpendicularity of the side surface of the mounting flange with respect to the center of rotation of the hub in use can be improved. Further, in the case of the present invention, the side surface of the mounting flange is processed while the hub is rotated alone, so that even when the chips (metal powder) generated during processing adhere to the surface of the hub, If the surface is washed after processing as in the first aspect of the invention, the chips can be removed from the surface. Moreover, according to the invention which concerns on Claim 2, it can prevent that the chip which arose with processing penetrate | invades into the space which installed the rolling element for processing work from the exterior.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows an example of an embodiment of the present invention corresponding to claims 1 and 2. The feature of this example is that the method of processing the outer surface 14 of the mounting flange 13 constituting the hub 8c is devised. Since the structure and operation of other parts, such as the overall structure of the wheel bearing unit including the hub 8c, are the same as those of the first example of the conventional structure shown in FIG. Is omitted or simplified, and the following description will focus on the features of this example.
[0016]
In the case of this example, before assembling the hub 8c, the outer ring 6, the inner ring 17 and the plurality of balls 19 and 19 (see FIG. 2 ) constituting the wheel bearing unit, The side 14 is finally processed. In the case of this example, prior to performing such processing, the hub 8c including the first inner ring raceway 15 and the base end side portion (the left side portion in FIG. 1) of the small diameter step portion 16 is included. On the outer peripheral surface of the intermediate portion, the portion indicated by the oblique lattice in the upper half of FIG. 1 is subjected to induction hardening over the entire periphery.
[0017]
In the case of this example, when the outer surface 14 of the mounting flange 13 is processed, an outer ring 29 for processing work, an inner ring 30 for processing work, and a plurality of rolling elements 31, 31 for processing work A pair of processing work holders 32 and 32 is used. Among these, the outer ring 29 for processing work is provided with double-row outer ring raceways 33a and 33b for processing work on the inner peripheral surface and a coupling flange 34 on the outer peripheral surface, and compressed air is provided inside the outer ring 29 for processing work. The passage 35 is provided in a state where the axially intermediate portions of the inner and outer peripheral surfaces of the processing work outer ring 29 communicate with each other. The downstream end of the compressed air supply pipe 36 is connected to the upstream end (the upper end in FIG. 1) of the compressed air passage 35. As a result, compressed air can be freely supplied from the compressed air supply pipe 36 into the compressed air passage 35, and the compressed air supplied into the compressed air passage 35 can be supplied radially inward of the outer ring 29 for processing work. It can be sent freely. Such a working work outer ring 29 is fixed to the housing 37 by connecting the connecting flange 34 to a housing 37 constituting a machine tool by a plurality of bolts 38.
[0018]
Further, each of the rolling elements 31 and 31 for processing work is a ball, like the rolling elements of the subject wheel bearing unit. A plurality of each of the rolling elements for machining operations 31 and 31 are held on the inner diameter side of each of the outer ring raceways 33a and 33b for machining operations and held in a freely rotatable manner by the holders 32 and 32 for machining operations. It is arranged. Each of these processing work holders 32, 32 is formed in an annular shape from a synthetic resin. A plurality of pockets 39, 39 are provided at equal intervals in the circumferential direction on one side surface in the axial direction. And inside each of these pockets 39, 39, the above-mentioned rolling elements for processing work 31, 31 are respectively held so as to be freely rollable and prevented from falling off from these pockets 39, 39. .
[0019]
Further, the processing work inner ring 30 is formed in a cylindrical shape as a whole, and a processing work inner ring raceway 40 is provided on the outer peripheral surface of the tip part (left end part in FIG. 1). Then, the tip end portion provided with the machining inner ring raceway 40 can be externally fitted to the small-diameter step portion 16 of the hub 8c without looseness, and the machining work inner ring raceway 40 is fitted in the outer fitting state. The dimensions of each part are regulated so as to be concentric with the small diameter step part 16. As shown in FIG. 1, the inner ring 30 for machining work is arranged on the inner side in the axial direction by disposing its tip on the inner diameter side of the outer ring raceway 33b for machining work on the inner side in the axial direction (right side in FIG. 1). The plurality of machining work rolling elements 31, 31 are sandwiched between the machining work outer ring raceway 33b and the machining work inner ring raceway 40. In this state, a seal ring 41 seals between the inner peripheral surface of the inner end portion of the outer ring 29 for processing work and the outer peripheral surface of the intermediate portion of the inner ring 30 for processing work. In this state, the machining inner ring 30 is rotatable with respect to the machining outer ring 29.
[0020]
When the outer surface 14 of the mounting flange 13 constituting the hub 8c is processed using the members 29 to 32 as described above, the inner diameter side of the members 29 to 32 as shown in FIG. The inner half of the hub 8c is inserted from the outside in the axial direction (left side in FIG. 1). As a result, the tip end portion of the inner ring 30 for machining work is fitted to the small-diameter step portion 16 of the hub 8c without rattling, and the outer ring for machining work outside the axial direction and the first inner ring raceway 15 of the hub 8c. The plurality of rolling elements 31 and 31 for machining work are sandwiched between the track 33a. The spline hole 22 provided at the center of the hub 8c is engaged with the male spline portion 43 provided at the tip of the drive shaft 42, and the outward direction provided on the outer peripheral surface of the drive shaft 42 near the tip. The outer end surface of the hub 8c is pressed by the flange-shaped pressing portion 44. As a result, the distal end surface of the inner ring 30 for machining work is brought into contact with the stepped surface 45 existing at the proximal end portion of the small-diameter stepped portion 16 of the hub 8c, so that each of the machining operations provided in double rows is provided. Appropriate preload is applied to the rolling elements 31, 31 respectively. Then, based on the application of the preload as described above, the rotation center of each of the members 8c and 30 is prevented from fluctuating when the hub 8c and the working work inner ring 30 described below are rotated.
[0021]
After the hub 8c is set as described above, the hub 8c and the machining work inner ring 30 are then rotated integrally with the machining work outer ring 29 by the drive shaft. At the same time, from the compressed air passage 35 provided inside the processing work outer ring 29, the above-mentioned existing between the inner peripheral surface of the processing work outer ring 29 and the outer peripheral surface of the hub 8 c and the processing work inner ring 30. Compressed air is sent into a space 46 in which a plurality of rolling elements 31, 31 for processing work are installed, and the compressed air is discharged to an external space through an opening on the outer end side of the space 46. In this state, the outer surface 14 of the mounting flange 13 constituting the hub 8c is turned by precision machining tools 47 and 47, and the outer surface 14 is finished to a predetermined shape and size.
[0022]
In this example in which the outer surface 14 of the mounting flange 13 is processed as described above, the perpendicularity of the outer surface 14 of the mounting flange 13 with respect to the rotation center of the hub 8c when the wheel bearing unit is used is improved. I can do things. That is, when the wheel bearing unit is used, the hub 8c and the inner ring 17 constituting the wheel bearing unit are connected to the first and second inner ring races 15 and 18 via the plurality of balls 19 and 19 by the outer ring 6. In a supported state (see FIG. 2 ). In other words, at the time of use, the hub 8c and the inner ring 17 rotate around a straight line connecting the center portions of the first and second inner ring raceways 15 and 18. The second inner ring raceway 18 provided on the outer peripheral surface of the inner ring 17 is concentric with the small-diameter step portion 16 of the hub 8c, which is a part to which the inner ring 17 is fitted. Therefore, when attention is paid only to the hub 8c, the hub 8c rotates around a straight line connecting the center portions of the first inner ring raceway 15 and the small diameter step portion 16 in use.
[0023]
On the other hand, in the case of the above-described example, when turning the outer surface 14 of the mounting flange 13, the hub 8 c and the inner ring 30 for machining work are separated into a plurality of rolling elements for machining work by the outer ring 29 for machining work. The first inner ring raceway 15 and the machining inner ring raceway 40 are rotated through 31 and 31 while being supported. In other words, at the time of machining, the hub 8c and the machining work inner ring 30 rotate around a straight line connecting the center axes of the first inner ring raceway 15 and the machining work inner ring raceway 40. Of these, the working inner ring raceway 40 is concentric with the small diameter step 16 of the hub 8c. Accordingly, when paying attention only to the hub 8c, during processing, the hub 8c forms a straight line connecting the center portions of the first inner ring raceway 15 and the small diameter step portion 16 as in the case of use described above. Rotate to center. For this reason, in the case of this example, the perpendicularity of the outer surface 14 of the mounting flange 13 with respect to the center of rotation of the hub 8c in use can be improved. As a result, the vibration of the braking friction surface provided in a part of the braking rotating body such as a rotor coupled to and supported by the outer surface 14 of the mounting flange 13 can be suppressed, and unpleasant noise and vibration generated during braking can be suppressed. .
[0024]
In the case of this example, the inner ring opening of the space 46 in which the respective rolling elements 31 and 31 for machining are installed is closed by the seal ring 41 during the machining. At the same time, the compressed air sent into the space 46 from the compressed air passage 35 is discharged to the outside through the outer end opening of the space 46, thereby preventing foreign matter from entering the outer end opening from the outside. is doing. Therefore, in the case of this example, it is possible to prevent chips (metal powder) generated during processing from entering the space 46 from the outside. In the case of this example, the processing is performed while rotating only the hub 8c before assembling the wheel bearing unit. For this reason, even when the chips (metal powder) generated during the processing adhere to the surface of the hub 8c, the chips can be removed from the surface by washing the surface after the processing. Therefore, in the case of this example, the chips damage the seal rings 21a and 21b, the surfaces of the balls 19 and 19 and the tracks 11a, 11b, 15, 18 and the like constituting the wheel bearing unit. You can prevent things.
[0025]
In the example described above, the compressed air passage is provided inside the outer ring for machining work. However, this compressed air passage may be provided inside the inner ring for machining work instead of the outer ring for machining work. it can.
[0026]
In the example of the embodiment described above, an example in which the present invention is applied to a wheel bearing unit for driving wheels has been described. However, the present invention is, for example, can be applied to wheel bearing unit for a driven wheel such as shown in Figure 3-4 above.
[0027]
【The invention's effect】
Since the method for manufacturing a wheel bearing unit of the present invention is configured and operates as described above, the squareness of the side surface of the mounting flange with respect to the center of rotation of the hub in use can be improved. As a result, the vibration of the braking friction surface provided at a part of the braking rotator coupled and supported on the side surface of the mounting flange can be suppressed, and unpleasant noise and vibration generated during braking can be suppressed. Further, since it is possible to prevent the seal ring, the surface of the rolling element, the raceway, and the like from being damaged by the chips generated by processing the side surface of the mounting flange, it is possible to manufacture a wheel bearing unit with good quality.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an example of an embodiment of the present invention.
FIG. 2 is a cross-sectional view showing a first example of a conventional structure in a state assembled to an automobile.
FIG. 3 is a sectional view showing the second example.
FIG. 4 is a sectional view showing the third example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Wheel 2 Rotor 3 Knuckle 4 Support hole 5 Wheel bearing unit 6 Outer ring 7 Bolt 8, 8a, 8b, 8c Hub 9 Stud 10 Nut 11a, 11b Outer ring track 12 Coupling flange 13 Mounting flange 14 Outer surface 15 First inner ring track 16 Small diameter step portion 17 Inner ring 18 Second inner ring raceway 19 Ball 20 Cage 21a, 21b Seal ring 22 Spline hole 23 Constant velocity joint 24 Spline shaft 25 Housing portion 26 Nut 27 Cylindrical portion 28 Caulking portion 29 Processing outer ring 30 Processing Working inner ring 31 Rolling element for machining work 32 Retainer for machining work 33a, 33b Outer ring raceway for machining work 34 Connection flange 35 Compressed air passage 36 Compressed air supply pipe 37 Housing 38 Bolt 39 Pocket 40 Working inner ring raceway 41 Seal ring 42 Shaft 43 male spline portion 44 pressing portion 45 stepped surface 46 space 47 precision machining bytes

Claims

An outer ring having a double row outer ring raceway on the inner peripheral surface, a hub in which a first inner ring raceway is directly formed in the middle portion of the outer peripheral surface and a small diameter step portion is formed on the inner end portion, and an outer fit to the small diameter step portion A fixed inner ring having a second inner ring raceway on the outer peripheral surface, and a plurality of rolling elements provided in a freely rotatable manner between each outer ring raceway and the first and second inner ring raceways. A mounting flange for coupling and fixing a braking rotator and a wheel on a side surface thereof in a state of use in a portion near the outer end of the outer peripheral surface of the hub. The side surface of the mounting flange includes the hub and the outer ring. Before assembling the inner ring and the rolling elements with each other, the hub was processed into a predetermined shape while rotating around the straight line connecting the center portions of the first inner ring raceway and the small diameter stepped portion. A method for producing a wheel bearing unit,
Before assembling the hub, the outer ring, the inner ring, and the rolling elements with each other, the hub is rotated around a straight line connecting the center portions of the first inner ring raceway and the small-diameter stepped portion. In order to process the side surface of the mounting flange into a predetermined shape,
The inner ring for processing work is fitted on the small diameter step part, and the first inner ring raceway and the inner ring raceway for processing work concentric with the small diameter step part provided on the outer peripheral surface of the inner ring for processing work are displaced. In a state where a plurality of rolling elements for machining work are provided so as to be freely rollable between the outer ring raceway for machining work provided on the inner peripheral surface of the outer ring for machining work supported in the blocked state, The hub is rotated with the inner ring for processing work, and the side surface of the mounting flange is processed into a predetermined shape, and then the hub is processed with the inner ring for processing work, the outer ring for processing work, and the rolling element for processing work. The wheel bearing unit is manufactured by removing the chips generated by processing the mounting flange attached to the surface by cleaning the surface of the hub .

An outer ring having a double row outer ring raceway on the inner peripheral surface, a hub in which a first inner ring raceway is directly formed in the middle portion of the outer peripheral surface and a small diameter step portion is formed on the inner end portion, and an outer fit to the small diameter step portion A fixed inner ring having a second inner ring raceway on the outer peripheral surface, and a plurality of rolling elements provided in a freely rotatable manner between each outer ring raceway and the first and second inner ring raceways. A mounting flange for coupling and fixing a braking rotator and a wheel on a side surface thereof in a state of use in a portion near the outer end of the outer peripheral surface of the hub. The side surface of the mounting flange includes the hub and the outer ring. Before assembling the inner ring and the rolling elements with each other, the hub was processed into a predetermined shape while rotating around the straight line connecting the center portions of the first inner ring raceway and the small diameter stepped portion. A method for producing a wheel bearing unit,
Before assembling the hub, the outer ring, the inner ring, and the rolling elements with each other, the hub is rotated around a straight line connecting the center portions of the first inner ring raceway and the small-diameter stepped portion. In order to process the side surface of the mounting flange into a predetermined shape,
The inner ring for processing work is fitted on the small diameter step part, and the first inner ring raceway and the inner ring raceway for processing work concentric with the small diameter step part provided on the outer peripheral surface of the inner ring for processing work are displaced. In a state where a plurality of rolling elements for machining work are provided so as to be freely rollable between the outer ring raceway for machining work provided on the inner peripheral surface of the outer ring for machining work supported in the blocked state, while the hub is rotated together with the inner ring above processing operations, provided between the hub and the outer peripheral surface and the machining working the inner peripheral surface of the outer ring of the machining operation for the inner ring, the plurality of machining operations for rolling By sending compressed air into the space where the moving body is installed through the outer ring for processing work or the compressed air passage provided inside the inner ring for processing work, the compressed air is jetted to the outside through the end opening of the space. while, the side of the mounting flange Performing processing method for a wheel bearing unit.