JP2004082320A

JP2004082320A - Method and apparatus for manufacturing wheel bearing unit

Info

Publication number: JP2004082320A
Application number: JP2003120073A
Authority: JP
Inventors: Toshiro Igari; 猪狩　敏朗; Yoshihiro Ozeki; 尾関　良寛
Original assignee: NSK Ltd
Current assignee: NSK Ltd
Priority date: 2002-07-01
Filing date: 2003-04-24
Publication date: 2004-03-18
Anticipated expiration: 2023-04-24
Also published as: JP3900108B2

Abstract

【課題】旋削加工後の位置決め筒部１６の外周面１７の寸法精度を向上させる。
【解決手段】チャック３７により外輪６を、スピンドル４１によりハブ８ａを、それぞれ互いに異なる回転速度で回転させる。この状態で、上記位置決め筒部１６の外周面１７にバイト４３ａを突き当てる事により、この外周面１７に旋削加工を施す。
【選択図】　図９An object of the present invention is to improve the dimensional accuracy of an outer peripheral surface 17 of a positioning cylinder 16 after turning.
A chuck (37) rotates an outer ring (6) and a spindle (41) rotates a hub (8a) at different rotational speeds. In this state, by turning the cutting tool 43a against the outer peripheral surface 17 of the positioning cylindrical portion 16, the outer peripheral surface 17 is turned.
[Selection] Fig. 9

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車輪用軸受ユニットの製造方法及び製造装置の改良に関する。
【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８に示す様な構造により、懸架装置を構成するナックル３に回転自在に支承している。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を構成する静止輪である外輪６を、複数本のボルト７により固定している。一方、上記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、外周面には固定側フランジ１２を、それぞれ形成している。この様な外輪６は、この固定側フランジ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。
【０００４】
これに対して、上記ハブ８は、ハブ本体１３と内輪１４とを組み合わせて成る。このうちのハブ本体１３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幅方向外側となる部分を言い、図１、４、５、８、９、１０、１２の左側。反対に、自動車への組み付け状態で幅方向中央側となる、図１、４、５、８、９、１０、１２の右側を、軸方向に関して内と言う。本明細書全体で同じ。）から突出した部分には、回転側フランジ１５を形成している。又、上記ハブ本体１３の外端面に位置決め筒部１６を形成している。この位置決め筒部１６の外周面１７は、上記ハブ本体１３と同心にしている。
【０００５】
上記ホイール１及びロータ２は、それぞれの内周縁部を上記位置決め筒部１６に外嵌した状態で、上記回転側フランジ１５の片側面（図示の例では外側面２７）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。この状態で、上記ホイール１及びロータ２と上記ハブ８とが互いに同心になる。又、上記ハブ本体１３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１８を、上記ハブ本体１３に対し直接形成している。更に、上記ハブ本体１３の内端部外周面に形成した小径段部１９に上記内輪１４を外嵌固定して、上記ハブ８を構成している。そして、この内輪１４の外周面に形成した第二の内輪軌道２０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。
【０００６】
これら各外輪軌道１１ａ、１１ｂと第一、第二の各内輪軌道１８、２０との間には、それぞれが転動体である玉２１、２１を複数個ずつ、それぞれ保持器２２、２２により保持した状態で転動自在に設けている。この構成により、背面組み合わせである複列アンギュラ型の玉軸受を構成し、上記外輪６の内側に上記ハブ８を、回転自在に、且つ、ラジアル荷重及びスラスト荷重を支承自在に支持している。尚、上記外輪６の両端部内周面と、上記ハブ本体１３の中間部外周面及び上記内輪１４の内端部外周面との間には、それぞれシールリング２３ａ、２３ｂを設けて、上記各玉２１、２１を設けた内部空間と外部とを遮断している。更に、図示の例は、駆動輪（ＦＲ車及びＲＲ車の後輪、ＦＦ車の前輪、４ＷＤ車の全輪）用の車輪用軸受ユニット５である為、上記ハブ本体１３の中心部に、スプライン孔２４を形成している。そして、このスプライン孔２４に、等速ジョイント２５のスプライン軸２６を挿入している。又、この状態で、上記ハブ本体１３の内端面から軸方向内方に突出した上記内輪１４の内端面を、上記等速ジョイント２５を構成するハウジング部３５の外端面により抑え付けている。
【０００７】
上述の様な車輪用軸受ユニット５の使用時には、図８に示す様に、外輪６をナックル３に固定すると共に、ハブ本体１３の回転側フランジ１５に、図示しないタイヤを組み合わせたホイール１及びロータ２を固定する。この際、前述した様に、ホイール１及びロータ２の内周縁部を位置決め筒部１６に外嵌する事により、これらホイール１及びロータ２と上記ハブ８とを互いに同心にする。又、このうちのロータ２と、上記ナックル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の制動用摩擦面である両側面に押し付ける。尚、本明細書中で制動用摩擦面とは、制動用回転体がロータである場合には、このロータの軸方向両側面を言い、制動用回転体がドラムである場合には、このドラムの内周面を言う。
【０００８】
ところで、自動車の高速走行時の安定性を向上させる為には、走行時に上記ホイール１及びロータ２が振れ回る（回転に伴って外周縁が径方向に変位する）のを防止する事が重要である。上述の様な構造で、走行時に上記ホイール１及びロータ２が振れ回るのを防止する為には、これらホイール１及びロータ２の幾何中心と上記ハブ８の回転中心とを一致させる必要がある。この為に従来から、このハブ８の中心軸と使用状態での回転中心とが一致するとの前提で、上記位置決め筒部１６の外周面１７の旋削加工を前記ハブ本体１３単体で行なう事により、上記位置決め筒部１６の外周面１７の中心軸と上記ハブ８の中心軸とを一致させる様にしている。そして、この位置決め筒部１６に上記ホイール１及びロータ２の外周縁をがたつきなく外嵌する事により、これらホイール１及びロータ２と上記ハブ８とを同心にする様にしている。
【０００９】
ところが、実際には、上記ハブ８の中心軸と使用状態での回転中心とが一致するとは限らず、一致しない場合には、上記ホイール１及びロータ２が振れ回るのを防止できなくなる。この為、これらホイール１及びロータ２の幾何中心と上記ハブ８の回転中心とを確実に一致させる事ができる技術の実現が望まれている。
【００１０】
【先発明の説明】
上述の様な要望に応えられる発明として、特願２００２−９４６５号に係る発明がある。図９〜１１は、この先発明に係る車輪用軸受ユニットの製造方法を実施する状況を示している。この図９〜１１に示した車輪用軸受ユニット５ａの構造に就いては、上述の図８に示した車輪用軸受ユニット５とほぼ同様であるが、上記図９〜１１に示した車輪用軸受ユニット５ａの場合、ハブ本体１３ａの小径段部１９に外嵌した内輪１４の内端面を、このハブ本体１３ａの内端部でこの内輪１４の内端面よりも軸方向内方に突出した部分を径方向外方に塑性変形させる事で形成したかしめ部２８により抑え付けている。これにより、上記内輪１４が上記小径段部１９から軸方向に抜け出るのを防止している。又、上記ハブ本体１３ａの外端面に設けた位置決め筒部１６の外周面１７のうち、基端部（内端部）をロータ２の内周縁部を外嵌する為の大径部３０とし、中間部乃至先端部（外端部）をホイール１（図８参照）の内周縁部を外嵌する為の小径部３１としている。これら大径部３０と小径部３１とは互いに同心で、段部３２により互いに連続している。
【００１１】
先発明の場合には、上述の様な車輪用軸受ユニット５ａに設けた位置決め筒部１６の外周面１７（大径部３０及び小径部３１）を、旋削加工により、ハブ８ａの回転中心と同心の円筒面に仕上げる。又、このハブ８ａの外端部外周面に設けた回転側フランジ１５ａの外側面２７を、旋削加工により、上記ハブ８ａの回転中心軸に対し直角な平坦面に仕上げる。この為に、先ず、上記位置決め筒部１６の外周面１７及び回転側フランジ１５ａの外側面２７に旋削加工を施すのに先立って、上記車輪用軸受ユニット５ａの構成各部材を、上記位置決め筒部１６の外周面１７及び回転側フランジ１５ａの外側面２７を除いて、所定の形状及び寸法に加工する。又、上記位置決め筒部１６の外周面１７及び回転側フランジ１５ａの外側面２７は、おおまかな形状及び寸法に加工する。次いで、上記車輪用軸受ユニット５ａの構成各部材を、図９に示す状態に組み立てる。
【００１２】
そして、この状態で、上記車輪用軸受ユニット５ａを、製造装置である旋削加工装置３６に組み付ける。この為に、上記外輪６の内端寄り部分の外周面４４を、上記旋削加工装置３６を構成する支持部材であるチャック３７の先端部により把持する。このチャック３７は、それぞれが円周方向に関して等間隔に設けられた複数（例えば３個）の爪部材３４、３４を備え、これら各爪部材３４、３４を、それぞれ径方向（図９の上下方向）に同期して変位自在としている。この様なチャック３７により上記外輪６の内端寄り部外周面４４を把持する場合には、径方向外方に変位させた上記各爪部材３４、３４の内径側に上記外輪６の内端部を挿入した状態で、これら各爪部材３４、３４を内径側に変位させる。これにより、それぞれが抑え面である、上記各爪部材３４、３４の先端部内周面を、それぞれ上記外輪６の内端寄り部外周面４４に当接させる。これと共に、やはりそれぞれが抑え面である、上記各爪部材３４、３４の先端面（図９、１０の左端面）を、上記固定側フランジ１２の内側面４５の内径寄り部分に突き当てて、上記外輪６の位置決めを図る。尚、図示の例では、上記各爪部材３４、３４の先端部内径側部分を、合成樹脂、アルミニウム、銅等の比較的軟らかい材料である保護材３８により構成している。そして、上記外輪６を上記チャック３７により把持した状態で、この外輪６の外周面が上記保護材３８の内周面にのみ接触し、この外輪６の内端寄り部分の外周面４４が傷付けられない様にしている。
【００１３】
又、図示の例では、前記回転側フランジ１５ａにスタッド９、９を固定した状態で、この回転側フランジ１５ａの外側面２７に容易に旋削加工を施せる様にすべく、この外側面２７の形状を工夫している。即ち、図示の例では、上記回転側フランジ１５ａの外側面２７の径方向中間部に、全周に亙る環状の凹部３９を形成している。そして、上記各スタッド９の基端部を固定する為の複数の取付孔２９の軸方向一端（図９、１０の左端）を、上記凹部３９内に開口させている。この凹部３９の径方向に関する幅Ｗ_３９は、上記各取付孔２９の内径ｄ_２９（図１０）よりも大きくしている（Ｗ_３９＞ｄ_２９）。上記各スタッド９の基端部を上記回転側フランジ１５ａに固定した状態で、これら各スタッド９のうちで上記回転側フランジ１５ａの外側面２７から突出した部分は、図９に鎖線αで示す、上記凹部３９の外周縁を含む仮想円筒面と、同じく鎖線βで示す、この凹部３９の内周縁を含む仮想円筒面との間に存在する、仮想の円筒状空間内に存在する。
【００１４】
そして、前記ハブ本体１３ａの中心部に設けたスプライン孔２４の内側に、上記旋削加工装置３６を構成する駆動部材であるスピンドル４１の先端部を、上記ハブ本体１３ａの外端側から挿入し、このスピンドル４１の先端部外周面に設けた雄スプライン部４２と上記スプライン孔２４とをスプライン係合させる。次いで、上記スピンドル４１を回転駆動する事により、上記ハブ本体１３ａをその中心軸を中心に回転させつつ、前記位置決め筒部１６の外周面１７、並びに、上記回転側フランジ１５ａの外側面２７のうち上記凹部３９の径方向両側部分に、３本の精密加工バイト４３ａ、４３ｂ、４３ｃを突き当てて、これら各部分に旋削加工を施す。そして、上記位置決め筒部１６の外周面１７、並びに、上記回転側フランジ１５ａの外側面２７を所定の形状及び寸法に仕上げる。
【００１５】
上述した様な先発明の場合には、車輪用軸受ユニット５ａの各構成部材を組み付けた後に、上記ハブ本体１３ａの外端面に設けた、ホイール１及びロータ２（図８参照）を外嵌する為の位置決め筒部１６の外周面１７、並びに、上記ハブ本体１３ａの外端部外周面に設けた、上記ホイール１及びロータ２を結合固定する為の回転側フランジ１５ａの外側面２７に旋削加工を施して、所定の形状及び寸法に仕上げる。この為、上記各構成部材の製造上不可避な寸法誤差や組み付け誤差に拘らず、上記ハブ本体１３ａの回転中心と上記位置決め筒部１６の外周面１７の幾何中心とを一致させる事ができる他、このハブ本体１３ａの回転中心に対する上記外側面２７の直角度を高くできる。
【００１６】
上述した各部の精度のうち、上記ハブ本体１３ａの回転中心と上記位置決め筒部１６の外周面１７の幾何中心とを一致させられる事は、走行時に上記ホイール１及びロータ２の振れ回りを抑え、高速走行時の安定性向上に寄与できる。又、上記外側面２７の直角度を向上させる事は、上記回転側フランジ１５ａに固定したロータ２の制動用摩擦面である両側面の振れを抑え、制動時に、ジャダーと呼ばれる不快な騒音を伴う振動の発生を防止できる事に繋がる。
【００１７】
尚、本発明に関連するその他の従来技術として、例えば、特許文献１〜３に記載された発明がある。これら特許文献１〜３に記載された発明は、転がり軸受ユニットを組み立てた状態で、ハブを構成する回転側フランジの側面に仕上げ加工を施す事により、このハブの回転中心に対するこの側面の直角度を向上させる事を目的としたものである。これら特許文献１〜３に記載された発明が、回転側フランジの側面のみを加工の対象としているのに対し、上述した先発明の場合には、この回転側フランジの側面だけでなく、位置決め筒部の外周面をも加工の対象としている。この為、上述した先発明の場合には、上記特許文献１〜３に記載された発明よりも有利な効果が得られる。
【００１８】
【特許文献１】
米国特許６，０７１，１８０号明細書
【特許文献２】
米国特許６，１５８，１２４号明細書
【特許文献３】
国際公開ＷＯ　００／７４８３３　Ａ１号公報
【００１９】
【発明が解決しようとする課題】
上述した様な先発明に係る車輪用軸受ユニットの製造方法には、未だ改良の余地がある。即ち、上述した先発明の場合、上記位置決め筒部１６の外周面１７並びに前記回転側フランジ１５ａの外側面２７の旋削加工は、前記外輪６を前記チャック３７により把持した状態で行なう。そして、この際に、これら外輪６とチャック３７とが同心になっていれば、上述した様な優れた効果を得られる。
【００２０】
ところが、それぞれが上記チャック３７により上記外輪６を把持する際の基準面となる、この外輪６の内端寄り部分の外周面４４及び前記固定側フランジ１２の内側面４５の、この外輪６の中心軸に対する同心度又は直角度が良好でなかったり、或は良好であっても、上記チャック３７により上記外輪６が正しく把持されない場合には、これらチャック３７と外輪６とが同心でなくなる。そして、図１２に誇張して示す様に、上記ハブ本体１３ａの回転中心Ｘが上記チャック３７の中心軸Ｙに対して傾いた状態となる。そして、この状態で上記位置決め筒部１６の外周面１７並びに上記回転側フランジ１５ａの外側面２７の旋削加工を行なうと、これら外周面１７及び外側面２７の形状精度や寸法精度が低下し、更にばらつく。
【００２１】
即ち、旋盤により被加工物の旋削加工を行なう場合、同じ加工点（切削工具の先端部の位置）を指定しても、被加工物の姿勢が正規の状態から傾いていると、この傾きの大きさ及び方向によって、加工後の被加工面の寸法が異なってしまう（ばらつく）。例えば、上記位置決め筒部１６の外周面１７の旋削加工を行なう場合、図１２（Ａ）に示す様に、上記位置決め筒部１６の外周面１７が加工点（鎖線Ｚ）に近付く方向に傾斜している場合には、同じく傾斜していない場合よりも、この外周面１７の旋削量が多くなる。これに対し、同図（Ｂ）に示す様に、上記位置決め筒部１６の外周面１７が加工点（鎖線Ｚ）から離れる方向に傾斜している場合には、同じく傾斜していない場合よりも、この外周面１７の旋削量が少なくなる｛図示の例では、加工点（鎖線Ｚ）がこの外周面１７に届いていないので、この外周面１７の旋削量がゼロになる｝。この為、上記ハブ本体１３ａの回転中心Ｘの傾きの大きさ及び方向によって、加工後の上記位置決め筒部１６の外周面１７の外径寸法が異なる（ばらつく）。この様な理由で加工後の寸法が異なる（ばらつく）事は、上記回転側フランジ１５ａの外側面２７に就いても同様である。
【００２２】
従って、上述の様な理由で上記位置決め筒部１６の外周面１７並びに上記回転側フランジ１５ａの外側面２７の寸法精度が低下し、更にばらつく事を防止する手段を提供する事が望まれる。
本発明の車輪用軸受ユニットの製造方法及び製造装置は、上述の様な事情に鑑みて発明したものである。
【００２３】
【課題を解決するための手段】
本発明の対象となる車輪用軸受ユニットは、前述した各車輪用軸受ユニット５、５ａと同様、静止輪と、ハブと、複数個の転動体とを備える。
このうちの静止輪は、静止側周面に複列の静止側軌道を有し、使用時に懸架装置に支持された状態で回転しない。
又、上記ハブは、外周面の外端寄り部分に回転側フランジを、上記静止側周面と対向する回転側周面にそれぞれが上記各静止側軌道と対向する複列の回転側軌道を、外端面に位置決め筒部を、それぞれ有する。
又、上記各転動体は、上記各静止側軌道と上記各回転側軌道との間に、それぞれ複数個ずつ転動自在に設けられている。
【００２４】そして、本発明の車輪用軸受ユニットの製造方法及び製造装置のうち、請求項１に記載した車輪用軸受ユニットの製造方法は、少なくとも上記静止輪と上記ハブと上記各転動体とを組み付けた後、この静止輪を支持部材により支持すると共に上記ハブの一部に駆動部材を係合させた状態で、これら支持部材と駆動部材とをそれぞれ自身の中心軸を中心として互いに異なる回転速度で回転させる事により、上記静止輪と上記ハブとをそれぞれ互いに異なる回転速度で回転させつつ、上記位置決め筒部の外周面と上記回転側フランジの外側面とのうちの少なくとも一方の面に旋削加工を施す事により、当該面を所定の形状（例えば、上記ハブの回転中心をその中心とする円筒面又はこのハブの回転中心と直交する平面）及び寸法に加工する。
【００２５】又、請求項２に記載した車輪用軸受ユニットの製造方法は、少なくとも上記静止輪と上記ハブと上記各転動体とを組み付けた後、この静止輪を支持部材により支持した状態で、先ず、この支持部材を自身の中心軸を中心として回転させる事により、この支持部材の中心軸を中心として上記静止輪と上記ハブとを共に回転させ、この回転時に上記位置決め筒部の外周面の径方向に関する振れが最大又は最小となる部分の円周方向の位相を検出する。次いで、上記支持部材を静止させる事により上記静止輪を静止させた状態で、上記ハブをこのハブの一部に係合させた駆動部材により回転させつつ、上記位置決め筒部の外周面のうち上記検出した円周方向の位相に対応する部分に切削工具を突き当てる事に基づき、当該外周面に旋削加工を施す事により、この位置決め筒部の外周面を所定の形状（例えば、上記ハブの回転中心をその中心とする円筒面）及び寸法に加工する。
【００２６】又、請求項３に記載した車輪用軸受ユニットの製造方法は、少なくとも上記静止輪と上記ハブと上記各転動体とを組み付けた後、この静止輪を支持部材により支持した状態で、上記ハブをこのハブの一部に係合させた駆動部材により回転させつつ、上記位置決め筒部の外周面に旋削加工を施す事により、この外周面を、目標とする外径よりも大きい外径を有する周面形状（例えば、上記ハブの回転中心を中心とする円筒面）に加工する。その後、上記外周面の外径と上記目標とする外径との寸法差を計測し、この計測した寸法差の分、更に上記位置決め筒部の外周面を旋削する事により、この位置決め筒部の外周面を、上記目標とする外径を有する周面形状（例えば、上記ハブの回転中心をその中心とする円筒面）に加工する。
【００２７】
又、本発明の車輪用軸受ユニットの製造方法及び製造装置のうち、請求項５に記載した車輪用軸受ユニットの製造装置は、上記静止輪を支持自在な支持部材と、上記ハブの一部に係合させた状態でこのハブを回転駆動自在な駆動部材とを備える。そして、上記支持部材の内部に圧縮空気通路を設けると共に、この圧縮空気通路の端部を、この支持部材の表面のうち、この支持部材により上記静止輪を支持する際にこの静止輪の表面に当接させるべき部分である抑え面に開口させている。
【００２８】
又、請求項７に記載した車輪用軸受ユニットの製造装置は、上記静止輪を支持自在な支持部材と、上記ハブの一部に係合させた状態でこのハブを回転駆動自在な駆動部材とを備える。そして、少なくとも上記静止輪と上記ハブと上記各転動体とを組み付けた後に、この静止輪を上記支持部材により支持した状態で、上記回転側フランジの外周面に対して径方向に遠近動自在な可動カバーを設けている。
【００２９】
又、請求項９に記載した車輪用軸受ユニットの製造装置は、内周面に複列の外輪軌道を有し、使用時に懸架装置に支持された状態で回転しない外輪と、外周面の外端寄り部分に回転側フランジを、同じく中間部乃至内端寄り部分に複列の内輪軌道を、外端面に位置決め筒部を、中心部にスプライン孔を、それぞれ有するハブと、上記各外輪軌道と上記各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た車輪用軸受ユニットのうち、上記外輪を支持自在な支持部材と、上記ハブの一部に係合させた状態でこのハブを回転駆動自在な駆動部材とを備える。そして、この駆動部材は、上記ハブの中心部に設けたスプライン孔に挿入自在な先端部の外周面に、このスプライン孔の内周面に形成された複数のスプライン溝に係合自在な係合凸部を、これら各スプライン溝の数よりも少ない数だけ備えているものである。
【００３０】
【作用】
上述の様に構成する本発明の車輪用軸受ユニットの製造方法及び製造装置のうち、請求項１〜４に記載した車輪用軸受ユニットの製造方法によれば、支持部材により静止輪を支持した状態で、この静止輪の中心軸（ハブの回転中心）が支持部材の中心軸に対して傾いている場合でも、旋削加工後の位置決め筒部の外周面（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更に、回転側フランジの外側面）の寸法精度を良好にでき、且つ、この寸法のばらつきを抑える事ができる。
【００３１】
即ち、請求項１、４に記載した車輪用軸受ユニットの製造方法の場合には、前述した様に、静止輪を支持する支持部材とハブの一部に係合させた駆動部材とをそれぞれ自身の中心軸を中心として互いに異なる回転速度で回転させる事により、これら静止輪とハブとを互いに異なる回転速度で回転させつつ、上記位置決め筒部の外周面及び上記回転側フランジの外側面に旋削加工を施す。この為、上記静止輪の中心軸（ハブの回転中心）が上記支持部材の中心軸に対して傾いている場合でも、上記位置決め筒部の外周面のうち径方向に関する振れが最大となる部分、並びに、上記回転側フランジの外側面のうち軸方向の振れが最大となる部分を基準に、それぞれ旋削加工を行なう事ができる。従って、これら各面の振れが最大となる部分からの切削工具の切り込み量を規制すれば、上記位置決め筒部の外周面及び上記回転側フランジの外側面の寸法精度を良好にでき、且つ、この寸法のばらつきを抑える事ができる。尚、旋削加工時の静止輪とハブとの回転方向を同方向とすれば、これら静止輪とハブとの相対回転速度を一定に保ったまま、上記各面の旋削加工速度を大きくする事ができる。この場合、対象となる車輪用軸受ユニットの許容回転数を越える回転速度での旋削加工も可能となる。
【００３２】
又、請求項２、４に記載した車輪用軸受ユニットの製造方法の場合には、やはり、位置決め筒部の外周面のうち、径方向に関する振れが最大又は最小となる部分を基準に旋削加工を行なう事ができる。従って、この径方向に関する振れが最大又は最小となる部分からの切削工具の切り込み量を規制すれば、上記位置決め筒部の外周面の外径寸法精度を良好にでき、且つ、この外径寸法のばらつきを抑える事ができる。
【００３３】
更に、請求項３、４に記載した車輪用軸受ユニットの製造方法の場合には、位置決め筒部の外周面の旋削加工の途中段階で、この外周面の外径を目標値に到達させる為の、その後の旋削量を確認できる。この為、上記位置決め筒部の外周面の外径寸法精度を良好にでき、且つ、この外径寸法のばらつきを抑える事ができる。
【００３４】
又、請求項５〜６及び請求項８に記載した車輪用軸受ユニットの製造装置の場合には、支持部材の抑え面に開口させた、圧縮空気通路の端部からの圧縮空気の漏れ状況を確認する事に基づいて、上記支持部材により静止輪が正しく支持されているか否かを確認できる。即ち、上記支持部材により静止輪が正しく支持されている場合には、この支持部材の抑え面に開口させた圧縮空気通路の端部が、上記静止輪の表面により塞がれる。従って、この状態では、上記圧縮空気通路の端部からの圧縮空気の漏れ量が、零乃至僅少になる。これに対し、上記支持部材により静止輪が正しく支持されていない場合には、この支持部材の抑え面に開口させた圧縮空気通路の端部が、上記静止輪の表面により十分には塞がれなくなる。従って、この状態では、上記圧縮空気通路の端部からの圧縮空気の漏れ量が、或る程度多くなる。
【００３５】
この為、上述した通り、上記圧縮空気通路の端部からの圧縮空気の漏れ状況を確認する事に基づいて、上記支持部材により静止輪が正しく支持されているか否かを確認できる。従って、この様な請求項４に記載した車輪用軸受ユニットの製造装置によれば、上記支持部材により静止輪が正しく支持されている（例えば、支持された状態でこれら支持部材と静止輪とが同心になっている）場合にのみ、位置決め筒部の外周面及び回転側フランジの外側面に旋削加工を施すと言った選択を行なえる。そして、この様な選択を行なえば、本発明の製造方法だけでなく、前述した先発明の製造方法を採用する場合でも、旋削加工後の位置決め筒部の外周面及び回転側フランジの外側面の寸法精度を良好にでき、且つ、この寸法のばらつきを抑える事ができる。
【００３６】
又、請求項７、８に記載した車輪用軸受ユニットの製造装置の場合には、位置決め筒部の外周面及び回転側フランジの外側面の旋削加工時に、旋削加工に伴って生じる切り粉等の異物が、上記回転側フランジよりも軸方向内側の空間に飛散する事を、可動カバーにより防止できる。この為、上記異物が複数の転動体を設置した空間内に侵入したり、この空間の両端開口を塞ぐシールリングが上記異物により傷付けられるのを防止できる。又、上記可動カバーは上記回転側フランジの外周面に対して径方向に遠近動自在である為、この可動カバーを径方向外方に退避させておけば、車輪用軸受ユニットをチャック等の支持部材に対して着脱する際に、上記可動カバーが邪魔になる事を防止できる。
【００３７】
又、請求項９に記載した車輪用軸受ユニットの製造装置の場合には、駆動部材の先端部外周面に設けた係合凸部の数が、ハブの中心部に設けたスプライン孔の内周面に形成した複数のスプライン溝の数よりも少ない。この為、上記駆動部材として、この駆動部材の先端部外周面を上記スプライン孔に対してスプライン係合自在な雄スプライン部とする場合に比べて、上記駆動部材の加工コストの低減を図れる。
【００３８】
【発明の実施の形態】
請求項１、４に対応する、本発明の実施の形態の第１例に就いて、前述の図９〜１１を参照しつつ説明する。本例の場合、前述の図９〜１１に示した先発明の場合と同様、先ず、ハブ本体１３ａを構成する位置決め筒部１６の外周面１７及び回転側フランジ１５ａの外側面２７に旋削加工を施すのに先立って、車輪用軸受ユニット５ａの構成各部材を、上記位置決め筒部１６の外周面１７及び回転側フランジ１５ａの外側面２７を除いて、所定の形状及び寸法に加工する。又、上記位置決め筒部１６の外周面１７及び回転側フランジ１５ａの外側面２７は、おおまかな形状及び寸法に加工する。次いで、上記車輪用軸受ユニット５ａの構成各部材を、図９に示す状態に組み立てる。
【００３９】
そして、この状態で、上記車輪用軸受ユニット５ａを、製造装置である旋削加工装置３６に組み付ける。即ち、前述した先発明の場合と同様、図９示す様に、静止輪である外輪６の内端寄り部分の外周面４４を、上記旋削加工装置３６を構成するチャック３７の先端部により把持する。これと共に、上記ハブ本体１３ａの中心部に設けたスプライン孔２４に、上記旋削加工装置３６を構成する駆動部材であるスピンドル４１の先端部外周面に設けた雄スプライン部４２をスプライン係合させる。尚、本例の場合、上記チャック３７は、自身の中心軸回りに回転駆動自在としている。
【００４０】
次いで、上記外輪６を上記チャック３７により、上記ハブ本体１３ａを上記スピンドル４１により、それぞれ同方向に、且つ、互いに異なる回転速度で回転させつつ、上記位置決め筒部１６の外周面１７、並びに、上記回転側フランジ１５ａの外側面２７のうち凹部３９の径方向両側部分に、３本の精密加工バイト４３ａ、４３ｂ、４３ｃを突き当てて、これら各部分に旋削加工を施す。
【００４１】
本例の場合、上述の様にして旋削加工を行なう際に、上記外輪６は、上記チャック３７の中心軸を中心に回転する。一方、上記ハブ本体１３ａは、自身の中心軸を中心とする回転と、上記チャック３７の中心軸を中心とする回転との、複合回転を行なう。この場合、上記チャック３７と上記外輪６とが同心になっていれば、このチャック３７の中心軸と上記ハブ本体１３ａの回転中心とが一致する為、前述した先発明の場合とほぼ同様の原理で（即ち、本例の場合には、上記ハブ本体１３ａだけでなく上記外輪６も回転しているが）、上記位置決め筒部１６の外周面１７、並びに、上記回転側フランジ１５ａの外側面２７を所定の形状及び寸法に仕上げる事ができる。
【００４２】
これに対し、それぞれが上記チャック３７により上記外輪６を把持する際の基準面となる、この外輪６の内端寄り部外周面４４及び前記固定側フランジ１２の内側面４５の、この外輪６の中心軸に対する同心度又は直角度が良好でない等の理由により、上記チャック３７と外輪６との互いの中心軸同士が傾いている場合には、上記ハブ本体１３ａは、自身の中心軸を中心に回転しつつ、上記チャック３７の中心軸を中心に振れ回る。この結果、上記位置決め筒部１６の外周面１７が、回転に伴って径方向に振れると共に、上記回転側フランジ１５ａの外側面２７が、回転に伴って軸方向に振れる。従って、これら位置決め筒部１６の外周面１７及び回転側フランジ１５ａの外側面２７に、前記各精密加工バイト４３ａ、４３ｂ、４３ｃを近づければ、これら各精密加工バイト４３ａ、４３ｂ、４３ｃが、上記位置決め筒部１６の外周面１７及び回転側フランジ１５ａの外側面２７の振れが最大となる部分に突き当たる。
【００４３】
そこで、本例の場合には、上記位置決め筒部１６の外周面１７及び回転側フランジ１５ａの外側面２７のうち、それぞれ振れが最大となる部分を基準に、これら外周面１７及び外側面２７の旋削加工を行なう事になる。即ち、これら外周面１７及び外側面２７のうち、それぞれ振れが最大となる部分を基準に、上記各精密加工バイト４３ａ、４３ｂ、４３ｃの切り込み量を調節して、上記外周面１７及び外側面２７を所定の形状及び寸法に仕上げる。この結果、本例の場合には、上記外輪６の中心軸（上記ハブ本体１３ａの回転中心）が上記チャック３７の中心軸に対し傾いている場合でも、上記外周面１７及び外側面２７の寸法精度を良好にでき、且つ、この寸法のばらつきを抑える事ができる。
【００４４】
次に、請求項２、４に対応する、本発明の実施の形態の第２例に就いて、やはり前述の図９〜１１を参照しつつ説明する。本例の場合、位置決め筒部１６の外周面１７及び回転側フランジ１５ａの外側面２７に旋削加工を施す際には、先ず、図９に示す様に、外輪６の内端寄り部分の外周面４４を、チャック３７の先端部により把持する。そして、この状態で、このチャック３７と共に上記外輪６とハブ本体１３ａとを、各玉２１、２１の転がり抵抗に基づいて共に回転させる。そして、この回転時に上記位置決め筒部１６の外周面１７の径方向に関する振れが最大（又は最小）となる部分の円周方向の位相を検出する。本例の場合には、上述の様に外輪６とハブ本体１３ａとを一体的に回転させながら、上記位置決め筒部１６の外周面１７の一部に図示しない位置検出装置を構成する検出棒（測定子）の先端部を摺接（若しくは非接触式センサの測定部を近接対向）させる事に基づいて、上記位置決め筒部１６の外周面１７の径方向に関する振れが最大（又は最小）となる部分の円周方向の位相を検出する。
【００４５】
上述の様にして位置決め筒部１６の外周面１７の径方向に関する振れが最大（又は最小）となる部分の円周方向の位相を検出したならば、次いで、上記チャック３７を静止させる事により上記外輪６を静止させた状態で、上記ハブ本体１３ａのスプライン孔２４にスピンドル４１の雄スプライン部４２をスプライン係合させる。そして、このスピンドル４１により上記ハブ本体１３ａを回転させつつ、上述の様に検出した円周方向の位相部分で、上記位置決め筒部１６の外周面１７に精密加工バイト４３ａを突き当てて、この外周面１７に旋削加工を施す。即ち、本例の場合には、上記位置決め筒部１６の外周面１７のうち、径方向に関する振れが最大（又は最小）となる部分を基準に上記精密加工バイト４３ａの切り込み量を調節して、上記外周面１７を所定の形状及び寸法に仕上げる。この結果、本例の場合には、上記外輪６の中心軸（上記ハブ本体１３ａの回転中心）が上記チャック３７の中心軸に対し傾いている場合でも、上記外周面１７の寸法精度を良好にでき、且つ、この寸法のばらつきを抑える事ができる。
【００４６】
次に、請求項３、４に対応する本発明の実施の形態の第３例に就いて、やはり前述の図９〜１１を参照しつつ説明する。本例の場合も、前述した第１例の場合と同様、位置決め筒部１６の外周面１７及び回転側フランジ１５ａの外側面２７に旋削加工を施す際には、先ず、図９に示す様に、外輪６をチャック３７の先端部により把持すると共に、ハブ本体１３ａのスプライン孔２４にスピンドル４１の雄スプライン部４２をスプライン係合させる。
【００４７】
そして、上記外輪６を静止させた状態で、上記スピンドル４１により上記ハブ本体１３ａを回転させつつ、上記位置決め筒部１６の外周面１７に精密加工バイト４３ａを突き当てて、この外周面１７に旋削加工を施す。本例の場合には、この様にしてこの外周面１７に旋削加工を施す事により、この外周面１７を目標とする外径よりも大きい外径を有する円筒面に加工する。そして、その後、上記外周面１７の外径と上記目標とする外径との寸法差を、図示しない計測装置により計測する。そして、この計測した寸法差の分、更に上記位置決め筒部１６の外周面１７に旋削加工を施す事により、この外周面１７を上記目標とする外径を有する円筒面に加工する。この様な本例の場合も、上記外輪６の中心軸（上記ハブ本体１３ａの回転中心）が上記チャック３７の中心軸に対して傾いている場合でも、上記外周面１７の寸法精度を良好にでき、且つ、この寸法のばらつきを抑える事ができる。
【００４８】
次に、図１〜３は、請求項５〜９に対応する、本発明の実施の形態の第４例を示している。尚、本例の特徴は、車輪用軸受ユニットの製造装置である、旋削加工装置３６ａの構造にある。車輪用軸受ユニット５の構造に就いては、前述の図８に示した車輪用軸受ユニット５と同様であり、製造方法に就いては、前述した先発明、或は上述した第１〜３例の場合と同様である。この為、同等部分には同一符号を付して、重複する説明を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。
【００４９】
本例の場合、チャック３７ａを構成する各爪部材３４ａの内部に、圧縮空気通路４８ａ、４８ｂを設けている。これら各圧縮空気通路４８ａ、４８ｂの先端部は、それぞれが抑え面である、上記各爪部材３４ａの先端部内周面４６と先端面４７とに開口させている。又、上記各圧縮空気通路４８ａ、４８ｂの基端部（図１の右端部）から、これら各圧縮空気通路４８ａ、４８ｂ内に、圧縮空気を供給自在としている。更に、これら各圧縮空気通路４８ａ、４８ｂ内の空気圧を、これら各圧縮空気通路４８ａ、４８ｂの基端側に設けた図示しない圧力センサにより検出自在としている。
【００５０】
本例の場合も、上述の様なチャック３７ａにより外輪６を把持する場合には、径方向外方に変位させた上記各爪部材３４ａの先端部内径側部分に、上記外輪６の内端部を挿入した状態で、これら各爪部材３４ａを径方向内方に変位させる。これにより、図１に示す様に、上記各爪部材３４ａの先端部内周面４６を上記外輪６の内端寄り部分の外周面４４に当接させると共に、同じく先端面４７を固定側フランジ１２の内側面４５に突き当てた状態とする。
【００５１】
又、この状態で、それぞれが上記チャック３７ａにより上記外輪６を把持する際の基準面となる、この外輪６の内端寄り部分の外周面４４及び固定側フランジ１２の内側面４５の、この外輪６の中心軸に対する同心度又は直角度が良好であり、且つ、上記チャック３７ａにより上記外輪６が正しく把持されている結果、これらチャック３７ａと外輪６とが同心になっている場合には、上記各爪部材３４ａの先端部内周面４６と上記外輪６の内端寄り部外周面４４との間、並びに、上記各爪部材３４ａの先端面４７と上記固定側フランジ１２の内側面４５との間に、それぞれ隙間が殆ど生じない状態となる。従って、この場合には、上記各爪部材３４ａの先端部内周面４６と先端面４７とにそれぞれの先端部を開口させた、上記各圧縮空気通路４８ａ、４８ｂ内に、これら各圧縮空気通路４８ａ、４８ｂの基端部から圧縮空気を供給しても、これら各圧縮空気通路４８ａ、４８ｂの先端開口から、当該圧縮空気が殆ど漏れ出さなくなる。
【００５２】
これに対し、上記外輪６の内端寄り部分の外周面４４及び上記固定側フランジ１２の内側面４５の、この外輪６の中心軸に対する同心度又は直角度が良好でなかったり、或は良好であっても上記チャック３７ａにより上記外輪６が正しく把持されていない結果、これらチャック３７ａと外輪６との中心軸同士が互いに傾いている場合には、上記各爪部材３４ａの先端部内周面４６と上記外輪６の内端寄り部外周面４４との間と、上記各爪部材３４ａの先端面４７と上記固定側フランジ１２の内側面４５との間とのうちの、少なくとも一方の間に、或る程度の隙間が生じる。従って、この場合には、上記各爪部材３４ａの先端部内周面４６と先端面４７とにそれぞれの先端部を開口させた、上記各圧縮空気通路４８ａ、４８ｂ内に、これら各圧縮空気通路４８ａ、４８ｂの基端部から圧縮空気を供給すると、少なくとも一方の圧縮空気通路４８ａ（４８ｂ）の先端開口から、上記隙間に見合った量の圧縮空気が漏れ出す。尚、本例の場合、上記各圧縮空気通路４８ａ、４８ｂの先端開口から圧縮空気が漏れ出す程度は、これら各圧縮空気通路４８ａ、４８ｂ内の空気圧を、前記図示しない圧力センサにより測定する事により確認できる。
【００５３】
従って、本例の場合、上記チャック３７ａにより上記外輪６を把持した状態で、上記圧力センサにより上記各圧縮空気通路４８ａ、４８ｂの先端開口から圧縮空気が漏れ出す程度を確認すれば、上記チャック３７ａにより上記外輪６が正しい姿勢（これらチャック３７ａと外輪６とが同心の状態で）で把持されているか否かを確認できる。そして、本例の場合には、上記チャック３７ａにより上記外輪６が正しい姿勢で把持されていると確認された場合にのみ、位置決め筒部１６の外周面１７及び回転側フランジ１５の外側面２７の旋削加工を行なう。この為、本例の場合には、上述した第１〜３例の製造方法だけでなく、前述した先発明に係る製造方法を採用した場合でも、旋削加工後の上記位置決め筒部１６の外周面１７並びに上記回転側フランジ１５の外側面２７の寸法精度を良好にでき、且つ、この寸法のばらつきを抑える事ができる。
【００５４】
又、本例の場合、ハブ本体１３を回転駆動する為のスピンドル４１ａの先端部５５の外周面は、雄スプライン部としていない。本例の場合、このスピンドル４１ａの先端部５５の外周面に、上記ハブ本体１３の中心部に設けたスプライン孔２４の内周面に形成された複数のスプライン溝４９、４９の数（本例の場合には、１２本）よりも少ない複数（本例の場合には、４本）の係合凸部５０、５０を、上記スピンドル４１ａの軸方向に、それぞれ円周方向に関して等間隔に設けている。そして、これら各係合凸部５０、５０を上記各スプライン溝４９、４９に係合自在としている。即ち、本例の場合、上記スピンドル４１ａの先端部５５の外周面の形状は、上記スプライン孔２４にスプライン係合自在な雄スプライン部を構成するスプライン凸部の数が、本来の数よりも少なくなった如き形状としている。そして、上記スピンドル４１ａの先端部５５の外周面の形状を、上述の様な形状とする事により、この先端部５５の外周面の加工コストを低減させている。又、本例の場合、上記各係合凸部５０、５０を設けた、上記スピンドル４１ａの先端部５５を、このスピンドル４１ａの基端側部分５６に対して着脱自在とする事により、この先端部５５を別のサイズ（或は別の形状）の先端部に交換できる様にしている。
【００５５】
又、上記各係合凸部５０、５０を上記各スプライン溝４９、４９に係合させる作業は、上記チャック３７ａにより上記外輪６を把持した後、上記スプライン孔２４の内側に上記スピンドル４１ａの先端部５５を、このスプライン孔２４の外端開口から挿入する事に基づいて行なう。従って、この様にスピンドル４１ａの先端部５５をスプライン孔２４に挿入する際には、上記各係合凸部５０、５０と上記各スプライン溝４９、４９との互いの周方向の位相を合わせておく必要がある。この位相合わせは、上記チャック３７ａにより上記外輪６を把持した後、上記スピンドル４１ａと上記ハブ本体１３とのうちの少なくとも一方の部材を回転させる事に基づいて行なえる。但し、この様にチャック３７ａにより外輪６を把持した後に上記位相合わせを行なうと、前記車輪用軸受ユニット５の製造作業の能率が低下する。
【００５６】
そこで、本例の場合には、上記チャック３７ａにより上記外輪６を把持するのに先立って、上記各スプライン溝４９、４９の円周方向の位相を、所定の方向に合わせておく。この様に各スプライン溝４９、４９の円周方向の位相を所定の方向に合わせる作業は、例えば、円周方向の位相を当該所定の方向に合わせておいたスプライン軸を、上記スプライン孔２４に挿入する事に基づいて行なう。そして、この様に各スプライン溝４９、４９の位相を所定の方向に合わせた後、この位相がずれない様にしながら上記車輪用軸受ユニット５を上記チャック３７ａ部分まで搬送し、このチャック３７ａにより上記外輪６を把持する。そして、この様にチャック３７ａにより外輪６を把持した状態で、上記各スプライン溝４９、４９の円周方向の位相が上記各係合凸部５０、５０の円周方向の位相に合致する様にしている。これにより、本例の場合には、上記チャック３７ａにより上記外輪６を把持した後、直ちに上記スピンドル４１ａの先端部５５を上記スプライン孔２４に挿入できる様にして、上記車輪用軸受ユニット５の製造作業の能率を向上させている。
【００５７】
尚、上記スピンドル４１ａの先端部５５を、このスピンドル４１ａの基端側部分５６に対して若干変位させる事ができる構造とすれば、上記スピンドル４１ａの先端部５５と上記スプライン孔２４との中心軸同士が多少ずれている場合でも、このスピンドル４１ａの先端部５５をこのスプライン孔２４の内側に挿入する事ができる。
【００５８】
又、本例の場合、上記チャック３７ａにより上記外輪６を把持した状態で、上記車輪用軸受ユニット５の上方と両側方との三方を囲む部分に、前記旋削加工装置３６ａに固定されて動かない固定カバー５１を設けると共に、この固定カバー５１の前方（図１の左方）に隣接する部分に、可動カバー５２を設けている。この可動カバー５２は、上記チャック３７ａにより上記外輪６を把持した状態で、前記回転側フランジ１５の上方に位置しており、上下方向に変位自在である。又、上記可動カバー５２の内周面５３は、この可動カバー５２を下方に変位させた状態で、上記回転側フランジ１５の外周面の上部及び両側部に近接対向自在な円弧状に形成している。更に、上記可動カバー５２の内周面５３の内端部に鍔部５４を設けている。そして、この内周面５３を上記回転側フランジ１５の外周面に近接対向させた状態で、上記鍔部５４の側面が上記回転側フランジ１５の内側面の外径側半部に近接対向する様にしている。
【００５９】
本例の場合、上記車輪用軸受ユニット５を上記旋削加工装置３６ａに対して着脱する際には、この着脱作業の邪魔にならない様に、上記可動カバー５２を上方に退避させておく。これに対し、前記位置決め筒部１６の外周面１７及び上記回転側フランジ１５の外側面２７の旋削加工を行なう際には、上記可動カバー５２を下方に変位させる事により、図１、３に示す様に、この可動カバー５２の内周面５３を上記回転側フランジ１５の外周面の上部及び両側部に近接対向させると共に、この内周面５３の内端部に設けた鍔部５４の側面を上記回転側フランジ１５の内側面の外径側部分に近接対向させる。そして、上記位置決め筒部１６の外周面１７及び上記回転側フランジ１５の外側面２７の旋削加工時に、旋削加工に伴って生じる切り粉等の異物が、上記回転側フランジ１５よりも軸方向内側の空間に飛散する事を、上記可動カバー５２及び前記固定カバー５１により防止する。
【００６０】
又、本例の場合、上述の様な旋削加工を、上記回転側フランジ１５に設けた取付孔２９、２９にスタッド９（図８、９参照）を挿入していない状態で行なう為、これら各取付孔２９、２９を通じて、上記回転側フランジ１５の軸方向両側の空間が連通している。この為、本例の場合には、上述の様な旋削加工時に、上記各取付孔２９、２９を通じて上記切り粉等の異物が上記回転側フランジ１５の軸方向内側の空間に侵入しない様にすべく、上記各取付孔２９、２９内を圧縮空気が、上記回転側フランジ１５の軸方向内側から軸方向外側に向けて流れる様にしている。尚、本例の場合には、上記可動カバー５２を上記回転側フランジ１５の上方にのみ設けたが、この様な可動カバーは、上記回転側フランジ１５の上下両側（中心軸を挟む両側）に設ける事もできる。
【００６１】
尚、本発明のうち、請求項１〜３に記載した車輪用軸受ユニットの製造方法、並びに、請求項５、７に記載した車輪用軸受ユニットの製造装置は、それぞれ図４に示す様な、静止輪が内輪５７、５７である車輪用軸受ユニット５ｂにも適用可能である。前述した各車輪用軸受ユニット５、５ａが駆動輪（ＦＦ車の前輪、ＦＲ車の後輪、４ＷＤ車の全輪）を懸架装置に対して回転自在に支持する為のものであったのに対し、図４に示した車輪用軸受ユニット５ｂは、従動輪（ＦＦ車の後輪、ＦＲ車の前輪）を懸架装置に対して回転自在に支持する為のものである。
【００６２】
この様な図４に示した車輪用軸受ユニット５ｂは、円筒状のハブ５８と、それぞれが静止輪である、短円筒状の１対の内輪５７、５７と、複数個の玉２１、２１とを備える。このうちのハブ５８は、外周面の外端寄り部分に回転側フランジ１５を、外端面に位置決め筒部１６を、それぞれ設けると共に、内周面の中間部乃至内端寄り部分に複列の外輪軌道５９、５９を形成している。又、上記各内輪５７、５７はそれぞれ、外周面に内輪軌道６０を形成すると共に、互いの軸方向端面同士を突き合わせた状態で、上記ハブ５８の内径側部分に、このハブ５８と同心に配置している。そして、上記各外輪軌道５９、５９と上記各内輪軌道６０、６０との間に上記各玉２１、２１を、それぞれ複数個ずつ転動自在に設けている。この様な車輪用軸受ユニット５ｂの使用時には、上記各内輪５７、５７を懸架装置を構成する固定軸に外嵌固定すると共に、上記位置決め筒部１６に外嵌した車輪及び制動用回転体を上記回転側フランジ１５に、複数本のスタッド９及び図示しないナットにより結合固定する。
【００６３】
そして、上述の様な車輪用軸受ユニット５ｂに本発明を適用すべく、上記位置決め筒部１６の外周面１７及び上記回転側フランジ１５の外側面２７に旋削加工を施す際には、上記各内輪５７、５７を支持部材により支持すると共に、上記ハブの一部に駆動部材を係合させる。この場合に、上記支持部材としては、例えば上記各内輪５７、５７を外嵌支持自在な軸部材を採用する事ができる。又、上記駆動部材としては、例えば上記ハブ５８の外周面を把持自在なチャックを採用する事ができる。
【００６４】
又、請求項１〜３に記載した車輪用軸受ユニットの製造方法、並びに、請求項５、７に記載した車輪用軸受ユニットの製造装置は、図５に示した様な車輪用軸受ユニット５ｃにも適用可能である。図５〜７は、本発明の実施の形態の第５例として、この様な車輪用軸受ユニット５ｃに対して請求項１〜３、５、７の発明を適用する場合の状況を示している。本例の車輪用軸受ユニット５ｃは、従動輪を懸架装置に対して回転自在に支持する為のものである。この様な車輪用軸受ユニット５ｃは、前述の図９に示した駆動輪用の車輪用軸受ユニット５ａとほぼ同様の構造を有するが、従動輪用である為、ハブ８ｂを構成するハブ本体１３ｂの中心部に、スプライン孔を設けていない。従って、本例の場合には、駆動部材であるスピンドル４１ｂの先端部を、上記ハブ本体１３ｂに係合させる事ができる様にすべく、このハブ本体１３ｂの一部に、上記スプライン孔の代わりとなる、被係合部を設ける必要がある。
【００６５】
そこで、本例の場合には、上記ハブ本体１３ｂの外端部内周面のうち、回転側フランジ１５ａの径方向内方に位置する部分で、互いに円周方向反対側となる２個所位置に、それぞれ被係合凸部６１、６１を形成している。これと共に、上記スピンドル４１ｂの外周面で、互いに円周方向反対側となる２個所位置に、それぞれ係合凸部６２、６２を、軸方向に形成している。そして、図５に示す様に、上記ハブ本体１３ｂの外端部内径側部分に上記スピンドル４１ｂの先端部を挿入する事により、上記各被係合凸部６１、６１に上記各係合凸部６２、６２の先端部を、それぞれ円周方向に関して互いの側面を当接させる状態で係合自在としている。そして、この様に係合させる事で、上記スピンドル４１ｂにより上記ハブ８ｂを回転駆動自在としている。
【００６６】
上述の様な車輪用軸受ユニット５ｃに対して請求項１〜３、５、７の発明を実施すべく、位置決め筒部１６の外周面１７及び上記回転側フランジ１５ａの外側面２７に旋削加工を施す際には、図５に示す様に、外輪６の内端部をチャック３７ｂにより把持する。この為に、本例の場合には、このチャック３７ｂを構成する各爪部材３４ｂ、３４ｂの内周面を、上記外輪６の内端部の外周面４４に密接させると共に、これら各爪部材３４ｂ、３４ｂの径方向内端寄り部分の外周面に設けた鍔部６３、６３の先端部（図５の左端部）を、上記外輪６を構成する固定側フランジ１２の内側面４５に突き当てる。これと共に、上記ハブ本体１３ｂの外端部内周面に設けた各被係合凸部６１、６１に、上記スピンドル４１ｂを構成する各係合突部６２、６２の先端部を係合させて、上記ハブ８ｂを回転駆動自在とする。その他の構成及び作用に就いては、前述した、請求項１〜３、５、７に対応する各実施の形態の場合と同様である。
【００６７】
尚、上述した第５例の様に、請求項１〜３、５、７に記載された発明を、中実体のハブを含む車輪用軸受ユニットに適用する場合、このハブ本体と駆動部材との係合部の構造は、上述の図５〜７に示した第５例のものに限定される事はない。特に、ハブ本体に設ける被係合部の構造は、このハブ本体の強度を損ねたり、或は周囲の機能を害さない限り、各種の構造を採用できる。
【００６８】
【発明の効果】
本発明の車輪用軸受ユニットの製造方法及び製造装置は、以上に述べた様に構成され作用する為、位置決め筒部の外周面及び回転側フランジの外側面の寸法精度を良好にでき、且つ、この寸法のばらつきを抑える事ができる。又、製造装置のコスト低減並びに機能向上を図れる。
【図面の簡単な説明】
【図１】本発明の実施の形態の第４例を示す断面図。
【図２】図１の拡大Ａ−Ａ断面図。
【図３】図１の左方から見た図。
【図４】本発明を適用できる車輪用軸受ユニットの別例を示す断面図。
【図５】本発明の実施の形態の第５例を示す断面図。
【図６】図５に示したハブのＢ−Ｂ断面図。
【図７】図５に示した駆動部材のＢ−Ｂ断面図。
【図８】本発明の対象となる車輪用軸受ユニットの組み付け状態の１例を示す断面図。
【図９】先発明の実施の形態の１例、並びに、本発明の実施の形態の第１〜３例を、位置決め筒部の外周面及び回転側フランジの外側面に旋削加工を施す状態で示す断面図。
【図１０】図９の部分拡大断面図。
【図１１】ハブを回転駆動する為のスピンドルを省略してこのハブを、図９の左方から見た図。
【図１２】旋削加工装置を構成するチャックの中心軸に対してハブの回転中心が傾いた状態を誇張して示す断面図。
【符号の説明】
１　　ホイール
２　　ロータ
３　　ナックル
４　　支持孔
５、５ａ、５ｂ、５ｃ　車輪用軸受ユニット
６　　外輪
７　　ボルト
８、８ａ、８ｂ　ハブ
９　　スタッド
１０　　ナット
１１ａ、１１ｂ　外輪軌道
１２　　固定側フランジ
１３、１３ａ、１３ｂ　ハブ本体
１４　　内輪
１５、１５ａ　回転側フランジ
１６　　位置決め筒部
１７　　外周面
１８　　第一の内輪軌道
１９　　小径段部
２０　　第二の内輪軌道
２１　　玉
２２　　保持器
２３ａ、２３ｂ　シールリング
２４　　スプライン孔
２５　　等速ジョイント
２６　　スプライン軸
２７　　外側面
２８　　かしめ部
２９　　取付孔
３０　　大径部
３１　　小径部
３２　　段部
３３　　内部空間
３４、３４ａ、３４ｂ　爪部材
３５　　ハウジング部
３６、３６ａ　旋削加工装置
３７、３７ａ、３７ｂ　チャック
３８　　保護材
３９　　凹部
４１、４１ａ、４１ｂ　スピンドル
４２　　雄スプライン部
４３ａ、４３ｂ、４３ｃ　精密加工バイト
４４　　外周面
４５　　内側面
４６　　内周面
４７　　先端面
４８ａ、４８ｂ　圧縮空気通路
４９　　スプライン溝
５０　　係合凸部
５１　　固定カバー
５２　　可動カバー
５３　　内周面
５４　　鍔部
５５　　先端部
５６　　基端側部分
５７　　内輪
５８　　ハブ
５９　　外輪軌道
６０　　内輪軌道
６１　　被係合凸部
６２　　係合凸部
６３　　鍔部[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an improvement in a manufacturing method and a manufacturing apparatus for a wheel bearing unit that supports a rotating body for braking, such as a vehicle wheel and a rotor or a drum.
[0002]
[Prior art]
A wheel 1 forming a vehicle wheel and a rotor 2 forming a disc brake as a braking device are rotatably supported by a knuckle 3 forming a suspension device, for example, by a structure as shown in FIG. That is, the outer ring 6 which is a stationary wheel 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 connected and fixed to a hub 8 constituting the wheel bearing unit 5 by a plurality of studs 9 and nuts 10.
[0003]
Double rows of outer raceways 11a and 11b are formed on the inner peripheral surface of the outer race 6, and fixed-side flanges 12 are formed on the outer peripheral surface. Such an outer ring 6 is fixed to the knuckle 3 by connecting the fixed flange 12 to the knuckle 3 with the bolts 7.
[0004]
On the other hand, the hub 8 is formed by combining the hub body 13 and the inner ring 14. Of the outer peripheral surface of the hub body 13, an outer end opening of the outer race 6 (the outer side in the axial direction means a part which is outward in the width direction when assembled to an automobile; , 8, 9, 10, and 12. Conversely, the right side of FIGS. 1, 4, 5, 8, 9, 10, and 12, which is the center in the width direction when assembled to an automobile, is defined as the inside in the axial direction. (The same applies to the entire specification). A positioning cylinder 16 is formed on the outer end surface of the hub body 13. The outer peripheral surface 17 of the positioning cylinder 16 is concentric with the hub body 13.
[0005]
The wheel 1 and the rotor 2 are connected to the studs 9 on one side surface (the outer side surface 27 in the illustrated example) of the rotating side flange 15 in a state where the inner peripheral edges of the wheel 1 and the rotor 2 are externally fitted to the positioning cylindrical portion 16. The nut 10 is connected and fixed. In this state, the wheel 1 and the rotor 2 and the hub 8 are concentric with each other. On the outer peripheral surface of the intermediate portion of the hub body 13, a portion of the first inner ring raceway 18 which is opposed to the outer one of the outer raceways 11 a of the double-row outer raceways 11 a and 11 b is attached to the hub body 13. On the other hand, it is formed directly. Further, the inner ring 14 is externally fitted and fixed to a small-diameter step portion 19 formed on the outer peripheral surface of the inner end portion of the hub main body 13 to constitute the hub 8. The second inner raceway 20 formed on the outer peripheral surface of the inner race 14 faces the inner outer raceway 11b of the double row outer raceways 11a and 11b.
[0006]
Between these outer raceways 11a, 11b and the first and second inner raceways 18, 20, a plurality of balls 21, 21, each of which is a rolling element, are held by holders 22, 22, respectively. It is provided so that it can roll freely in the state. With this configuration, a double-row angular contact type ball bearing as a rear combination is formed, and the hub 8 is supported inside the outer ring 6 so as to be rotatable and capable of supporting a radial load and a thrust load. Seal rings 23a and 23b are provided between inner peripheral surfaces of both ends of the outer ring 6 and outer peripheral surfaces of an intermediate portion of the hub body 13 and an inner end of the inner ring 14, respectively. The interior space provided with 21, 21 is shielded from the outside. Further, the illustrated example is a wheel bearing unit 5 for driving wheels (rear wheels of FR and RR vehicles, front wheels of FF vehicles, all wheels of 4WD vehicles). A spline hole 24 is formed. The spline shaft 26 of the constant velocity joint 25 is inserted into the spline hole 24. Further, in this state, the inner end surface of the inner race 14 protruding inward in the axial direction from the inner end surface of the hub body 13 is suppressed by the outer end surface of the housing portion 35 constituting the constant velocity joint 25.
[0007]
When the wheel bearing unit 5 as described above is used, as shown in FIG. 8, the outer ring 6 is fixed to the knuckle 3 and the wheel 1 and the rotor are combined with a rotating side flange 15 of a hub body 13 and a tire (not shown). Fix 2 At this time, as described above, the wheel 1 and the rotor 2 and the hub 8 are concentric with each other by fitting the inner peripheral edges of the wheel 1 and the rotor 2 to the positioning cylinder 16. The rotor 2 is combined with a support and a caliper (not shown) fixed to the knuckle 3 to form a disc brake for braking. At the time of braking, a pair of pads provided so as to sandwich the rotor 2 is pressed against both side surfaces of the rotor 2 which are friction surfaces for braking. In the present specification, the friction surface for braking refers to both axial sides of the rotor when the rotating body for braking is a rotor, and the drum when the rotating body for braking is a drum. Of the inner circumference.
[0008]
By the way, in order to improve the stability at the time of high-speed running of an automobile, it is important to prevent the wheel 1 and the rotor 2 from wobbling (the outer peripheral edge is displaced in the radial direction with the rotation) during running. is there. In order to prevent the wheel 1 and the rotor 2 from swinging during traveling with the above-described structure, it is necessary to match the geometric center of the wheel 1 and the rotor 2 with the rotation center of the hub 8. For this reason, conventionally, on the premise that the center axis of the hub 8 coincides with the rotation center in use, the turning of the outer peripheral surface 17 of the positioning cylinder 16 is performed by the hub body 13 alone. The central axis of the outer peripheral surface 17 of the positioning cylinder 16 and the central axis of the hub 8 are aligned. By fitting the outer peripheral edges of the wheel 1 and the rotor 2 to the positioning cylinder 16 without looseness, the wheel 1 and the rotor 2 are concentric with the hub 8.
[0009]
However, actually, the center axis of the hub 8 does not always coincide with the center of rotation in use, and if they do not coincide, it becomes impossible to prevent the wheel 1 and the rotor 2 from swinging around. For this reason, it is desired to realize a technology that can surely match the geometric center of the wheel 1 and the rotor 2 with the rotation center of the hub 8.
[0010]
[Description of Prior Invention]
As an invention that can meet the above-mentioned demand, there is an invention according to Japanese Patent Application No. 2002-9465. 9 to 11 show a situation in which the method of manufacturing a wheel bearing unit according to the prior invention is carried out. The structure of the wheel bearing unit 5a shown in FIGS. 9 to 11 is almost the same as that of the wheel bearing unit 5 shown in FIG. 8, but the wheel bearing unit shown in FIGS. In the case of the unit 5a, the inner end face of the inner ring 14 fitted to the small-diameter step portion 19 of the hub body 13a corresponds to the portion of the inner end of the hub body 13a projecting axially inward from the inner end face of the inner ring 14. It is suppressed by a caulking portion 28 formed by plastically deforming radially outward. This prevents the inner ring 14 from coming out of the small-diameter step portion 19 in the axial direction. Further, of the outer peripheral surface 17 of the positioning tubular portion 16 provided on the outer end surface of the hub body 13a, the base end (inner end) is a large diameter portion 30 for externally fitting the inner peripheral edge of the rotor 2, The middle part or the tip part (outer end part) is a small diameter part 31 for externally fitting the inner peripheral part of the wheel 1 (see FIG. 8). The large diameter portion 30 and the small diameter portion 31 are concentric with each other and continuous with each other by a step portion 32.
[0011]
In the case of the prior invention, the outer peripheral surface 17 (the large-diameter portion 30 and the small-diameter portion 31) of the positioning cylindrical portion 16 provided in the above-described wheel bearing unit 5a is concentric with the rotation center of the hub 8a by turning. Finish on a cylindrical surface. The outer surface 27 of the rotating flange 15a provided on the outer peripheral surface of the outer end of the hub 8a is turned into a flat surface perpendicular to the rotation center axis of the hub 8a by turning. For this purpose, first, before turning the outer peripheral surface 17 of the positioning cylinder 16 and the outer surface 27 of the rotating flange 15a, the constituent members of the wheel bearing unit 5a are replaced with the positioning cylinder. Except for the outer peripheral surface 17 of 16 and the outer surface 27 of the rotary side flange 15a, it is processed into a predetermined shape and dimensions. Further, the outer peripheral surface 17 of the positioning cylinder 16 and the outer surface 27 of the rotating flange 15a are processed into rough shapes and dimensions. Next, the components of the wheel bearing unit 5a are assembled in the state shown in FIG.
[0012]
Then, in this state, the wheel bearing unit 5a is assembled to a turning device 36 which is a manufacturing device. For this purpose, the outer peripheral surface 44 of the outer ring 6 near the inner end is gripped by the tip of a chuck 37 which is a support member of the turning device 36. The chuck 37 includes a plurality (for example, three) of claw members 34, 34 provided at regular intervals in the circumferential direction, and each of the claw members 34, 34 is placed in the radial direction (the vertical direction in FIG. 9). ) And can be displaced synchronously. When the outer peripheral surface 44 near the inner end of the outer race 6 is gripped by such a chuck 37, the inner end of the outer race 6 is disposed on the inner diameter side of each of the claw members 34, 34 displaced radially outward. Are inserted, the respective claw members 34, 34 are displaced toward the inner diameter side. Thereby, the inner peripheral surfaces of the claw members 34, 34, each of which is a pressing surface, are brought into contact with the outer peripheral surface 44 of the outer race 6 near the inner end. At the same time, the tip surfaces (the left end surfaces in FIGS. 9 and 10) of the claw members 34, 34, which are also the holding surfaces, abut against the inner diameter portion of the inner surface 45 of the fixed side flange 12, The outer ring 6 is positioned. In the illustrated example, the inner diameter side portions of the claw members 34, 34 are formed of a protective material 38, which is a relatively soft material such as synthetic resin, aluminum, or copper. When the outer ring 6 is gripped by the chuck 37, the outer peripheral surface of the outer ring 6 contacts only the inner peripheral surface of the protection member 38, and the outer peripheral surface 44 of the outer ring 6 near the inner end is damaged. I do not have.
[0013]
In the illustrated example, the studs 9, 9 are fixed to the rotary side flange 15a, and the outer side surface 27 of the rotary side flange 15a can be easily turned. Is devised. That is, in the illustrated example, an annular concave portion 39 is formed over the entire circumference at a radially intermediate portion of the outer side surface 27 of the rotating side flange 15a. One end (left end in FIGS. 9 and 10) of a plurality of mounting holes 29 for fixing the base end of each stud 9 is opened in the recess 39. The width W of the recess 39 in the radial direction ₃₉ Is the inner diameter d of each of the mounting holes 29. ₂₉ (FIG. 10). ₃₉ > D ₂₉ ). With the base end of each stud 9 fixed to the rotating flange 15a, a portion of each stud 9 protruding from the outer surface 27 of the rotating flange 15a is indicated by a chain line α in FIG. It exists in a virtual cylindrical space existing between a virtual cylindrical surface including the outer peripheral edge of the concave portion 39 and a virtual cylindrical surface including the inner peripheral edge of the concave portion 39 also indicated by a chain line β.
[0014]
Then, the tip of the spindle 41, which is a driving member of the turning device 36, is inserted into the inside of the spline hole 24 provided at the center of the hub body 13a from the outer end side of the hub body 13a. The male spline portion 42 provided on the outer peripheral surface of the distal end portion of the spindle 41 and the spline hole 24 are spline-engaged. Next, by rotating the spindle 41, the hub main body 13a is rotated about its central axis, and the outer peripheral surface 17 of the positioning cylinder 16 and the outer surface 27 of the rotary flange 15a are rotated. Three precision cutting tools 43a, 43b, 43c are abutted against both radial portions of the concave portion 39, and each of these portions is subjected to turning. Then, the outer peripheral surface 17 of the positioning cylinder 16 and the outer surface 27 of the rotating flange 15a are finished to predetermined shapes and dimensions.
[0015]
In the case of the above-described prior invention, after assembling the respective components of the wheel bearing unit 5a, the wheel 1 and the rotor 2 (see FIG. 8) provided on the outer end surface of the hub body 13a are externally fitted. Turning on the outer peripheral surface 17 of the positioning cylindrical portion 16 and the outer surface 27 of the rotating flange 15a provided on the outer peripheral surface of the outer end portion of the hub body 13a for coupling and fixing the wheel 1 and the rotor 2. To finish to a predetermined shape and dimensions. Therefore, irrespective of dimensional errors and assembling errors inevitable in the manufacture of the respective components, the center of rotation of the hub body 13a and the geometric center of the outer peripheral surface 17 of the positioning cylinder 16 can be made coincident with each other. The perpendicularity of the outer surface 27 to the center of rotation of the hub body 13a can be increased.
[0016]
Of the above-described accuracy of each part, the fact that the rotation center of the hub body 13a and the geometric center of the outer peripheral surface 17 of the positioning cylinder part 16 are made to coincide with each other suppresses the whirling of the wheel 1 and the rotor 2 during traveling, This can contribute to improved stability during high-speed running. Improving the perpendicularity of the outer side surface 27 suppresses run-out of both side surfaces which are the friction surfaces for braking of the rotor 2 fixed to the rotating side flange 15a, and causes an unpleasant noise called judder at the time of braking. This leads to prevention of generation of vibration.
[0017]
In addition, as other conventional techniques related to the present invention, for example, there are inventions described in Patent Documents 1 to 3. The inventions described in Patent Documents 1 to 3 are characterized in that, in a state where the rolling bearing unit is assembled, the side face of the rotating side flange constituting the hub is subjected to finish processing, so that the squareness of the side face with respect to the rotation center of the hub is obtained. It is intended to improve the quality. While the inventions described in Patent Documents 1 to 3 target only the side surface of the rotating flange, in the case of the above-described prior invention, not only the side surface of the rotating flange but also the positioning cylinder The outer peripheral surface of the part is also processed. Therefore, in the case of the above-described prior invention, advantageous effects can be obtained as compared with the inventions described in Patent Documents 1 to 3.
[0018]
[Patent Document 1]
U.S. Pat. No. 6,071,180
[Patent Document 2]
U.S. Pat. No. 6,158,124
[Patent Document 3]
International Publication WO 00/74833 A1
[0019]
[Problems to be solved by the invention]
There is still room for improvement in the manufacturing method of the wheel bearing unit according to the above-mentioned invention as described above. That is, in the case of the above-described prior invention, the turning of the outer peripheral surface 17 of the positioning cylindrical portion 16 and the outer surface 27 of the rotating flange 15a are performed while the outer ring 6 is gripped by the chuck 37. At this time, if the outer race 6 and the chuck 37 are concentric, the above-described excellent effects can be obtained.
[0020]
However, the center of the outer ring 6 at the outer peripheral surface 44 of the portion near the inner end of the outer ring 6 and the inner surface 45 of the fixed side flange 12, which serve as reference surfaces when the outer ring 6 is gripped by the chuck 37, respectively. Even if the concentricity or the perpendicularity with respect to the shaft is not good, or if the outer ring 6 is not properly gripped by the chuck 37, the chuck 37 and the outer ring 6 are not concentric. Then, as shown exaggeratedly in FIG. 12, the rotation center X of the hub body 13a is inclined with respect to the center axis Y of the chuck 37. When the outer peripheral surface 17 of the positioning cylindrical portion 16 and the outer surface 27 of the rotary flange 15a are turned in this state, the accuracy of the outer peripheral surface 17 and the outer surface 27 is reduced. Vary.
[0021]
That is, when the workpiece is turned by a lathe, even if the same processing point (the position of the tip of the cutting tool) is designated, if the posture of the workpiece is inclined from a normal state, the inclination of the inclination is reduced. Depending on the size and the direction, the dimensions of the processed surface after processing differ (varies). For example, when turning the outer peripheral surface 17 of the positioning cylinder 16, as shown in FIG. 12A, the outer peripheral surface 17 of the positioning cylinder 16 is inclined in a direction approaching the processing point (chain line Z). In this case, the turning amount of the outer peripheral surface 17 is larger than that in the case where it is not inclined. On the other hand, as shown in FIG. 7B, when the outer peripheral surface 17 of the positioning cylindrical portion 16 is inclined in a direction away from the processing point (dashed line Z), it is more likely than when it is not inclined. However, the turning amount of the outer peripheral surface 17 is reduced. In the example shown in the figure, since the machining point (dashed line Z) does not reach the outer peripheral surface 17, the turning amount of the outer peripheral surface 17 becomes zero. Therefore, the outer diameter of the outer peripheral surface 17 of the positioning cylindrical portion 16 after processing varies (varies) depending on the magnitude and direction of the inclination of the rotation center X of the hub body 13a. For such reasons, the dimensions after processing are different (fluctuations) also apply to the outer side surface 27 of the rotating side flange 15a.
[0022]
Therefore, it is desired to provide a means for preventing the dimensional accuracy of the outer peripheral surface 17 of the positioning cylindrical portion 16 and the outer peripheral surface 27 of the rotating flange 15a from decreasing for the above-mentioned reason, and further preventing the variance.
The manufacturing method and the manufacturing apparatus of the wheel bearing unit of the present invention have been invented in view of the above-mentioned circumstances.
[0023]
[Means for Solving the Problems]
The wheel bearing unit to which the present invention is applied includes a stationary wheel, a hub, and a plurality of rolling elements, similarly to the wheel bearing units 5, 5a described above.
Of these, the stationary wheel has multiple rows of stationary tracks on the stationary peripheral surface, and does not rotate while being supported by the suspension device during use.
In addition, the hub has a rotating flange at a portion near the outer end of the outer peripheral surface, and a double row of rotating side orbits each facing the stationary side orbit on the rotating side peripheral surface facing the stationary side peripheral surface, It has a positioning cylinder on the outer end face.
Further, a plurality of rolling elements are provided between each of the stationary-side orbits and each of the rotating-side orbits so as to freely roll.
In the method and apparatus for manufacturing a bearing unit for a wheel according to the present invention, the method for manufacturing a bearing unit for a wheel according to the first aspect includes at least the stationary wheel, the hub, and the rolling elements. After the assembling, the stationary wheel is supported by the supporting member and the driving member is engaged with a part of the hub, and the supporting member and the driving member are rotated at different rotational speeds about their own central axes. By rotating the stationary wheel and the hub at different rotational speeds from each other, at least one of the outer peripheral surface of the positioning cylindrical portion and the outer peripheral surface of the rotating flange is turned. The surface is added to a predetermined shape (for example, a cylindrical surface having the center of rotation of the hub as its center or a plane orthogonal to the center of rotation of the hub) and dimensions. To.
According to a second aspect of the present invention, in the method of manufacturing a bearing unit for a wheel, at least the stationary wheel, the hub, and the rolling elements are assembled, and the stationary wheel is supported by a supporting member. First, by rotating the support member about its own central axis, the stationary wheel and the hub are rotated together about the central axis of the support member. The phase in the circumferential direction of the portion where the radial fluctuation is maximum or minimum is detected. Then, in a state where the stationary wheel is stationary by stopping the support member, the hub is rotated by a driving member engaged with a part of the hub, and the outer circumferential surface of the positioning cylindrical portion is rotated. The outer peripheral surface of the positioning cylindrical portion is formed into a predetermined shape (for example, by rotating the hub) by turning the outer peripheral surface based on abutment of a cutting tool against a portion corresponding to the detected phase in the circumferential direction. A cylindrical surface with its center at the center) and dimensions.
According to a third aspect of the present invention, in the method of manufacturing a bearing unit for a wheel, at least the stationary wheel, the hub, and the rolling elements are assembled, and the stationary wheel is supported by a support member. By turning the outer peripheral surface of the positioning cylindrical portion while rotating the hub by a driving member engaged with a part of the hub, the outer peripheral surface is formed to have an outer diameter larger than a target outer diameter. (For example, a cylindrical surface centered on the center of rotation of the hub). Thereafter, a dimensional difference between the outer diameter of the outer peripheral surface and the target outer diameter is measured, and by turning the outer peripheral surface of the positioning cylindrical portion by the measured dimensional difference, the positioning cylindrical portion is The outer peripheral surface is processed into a peripheral shape having the target outer diameter (for example, a cylindrical surface whose center is the rotation center of the hub).
[0027]
Further, among the manufacturing method and the manufacturing apparatus of the wheel bearing unit of the present invention, the manufacturing apparatus of the wheel bearing unit according to claim 5 includes a supporting member capable of supporting the stationary wheel and a part of the hub. And a driving member capable of driving the hub to rotate in the engaged state. A compressed air passage is provided inside the support member, and an end of the compressed air passage is formed on the surface of the stationary wheel when the stationary member is supported by the support member on the surface of the support member. An opening is provided on the holding surface, which is the part to be brought into contact.
[0028]
According to a seventh aspect of the present invention, there is provided an apparatus for manufacturing a bearing unit for a wheel, comprising: a support member capable of supporting the stationary wheel; and a drive member capable of rotationally driving the hub while being engaged with a part of the hub. Is provided. Then, after assembling at least the stationary wheel, the hub, and the rolling elements, the stationary wheel is supported by the support member, and is movable in a radial direction with respect to the outer peripheral surface of the rotating flange. A movable cover is provided.
[0029]
An apparatus for manufacturing a bearing unit for a wheel according to claim 9, wherein the outer peripheral surface has a double row of outer raceways on the inner peripheral surface and does not rotate while being supported by the suspension device during use, and an outer end of the outer peripheral surface. A hub having a rotating side flange in a deviated portion, a double row of inner ring raceways in an intermediate portion or an inner end deviated portion, a positioning cylinder portion in an outer end surface, and a spline hole in a center portion; A wheel bearing unit having a plurality of rolling elements provided so as to freely roll between each of the inner ring raceways, a support member capable of supporting the outer ring and a part of the hub. And a driving member that can rotate this hub in a rotating state. The driving member is provided on an outer peripheral surface of a tip portion which can be inserted into a spline hole provided in a center portion of the hub, and is engaged with a plurality of spline grooves formed on an inner peripheral surface of the spline hole. The number of protrusions is smaller than the number of each spline groove.
[0030]
[Action]
According to the method for manufacturing a bearing unit for a wheel of the present invention configured as described above, according to the method for manufacturing a bearing unit for a wheel according to any one of claims 1 to 4, the stationary member is supported by the supporting member. Even if the center axis of the stationary wheel (the center of rotation of the hub) is inclined with respect to the center axis of the support member, the outer peripheral surface of the positioning cylinder after turning (the wheel bearing unit according to claim 1). In the case of the manufacturing method of (1), the dimensional accuracy of the outer side surface of the rotating side flange) can be further improved, and the dimensional variation can be suppressed.
[0031]
That is, in the case of the manufacturing method of the wheel bearing unit according to the first and fourth aspects, as described above, the supporting member for supporting the stationary wheel and the driving member engaged with a part of the hub are respectively themselves. The stationary wheel and the hub are rotated at different rotational speeds by rotating the stationary wheel and the hub at different rotational speeds about the center axis of the center shaft, while turning the outer peripheral surface of the positioning cylinder portion and the outer peripheral surface of the rotary side flange. Is applied. For this reason, even when the center axis of the stationary wheel (the center of rotation of the hub) is inclined with respect to the center axis of the support member, a portion of the outer peripheral surface of the positioning cylinder portion where the radial deflection becomes maximum, In addition, turning can be performed on the basis of a portion of the outer side surface of the rotating side flange where the axial runout is maximum. Therefore, if the amount of cutting of the cutting tool from the portion where the runout of each of these surfaces is maximized is regulated, the dimensional accuracy of the outer peripheral surface of the positioning cylindrical portion and the outer surface of the rotating flange can be improved, and Variations in dimensions can be suppressed. If the rotation direction of the stationary wheel and the hub during turning is the same, it is possible to increase the turning speed of each surface while maintaining the relative rotational speed between the stationary wheel and the hub constant. it can. In this case, turning at a rotation speed exceeding the permissible rotation speed of the target wheel bearing unit is also possible.
[0032]
Also, in the case of the method for manufacturing a wheel bearing unit according to claims 2 and 4, the turning process is performed on the basis of the portion of the outer peripheral surface of the positioning cylinder portion where the runout in the radial direction is maximum or minimum. You can do it. Therefore, if the amount of cutting of the cutting tool from the portion where the runout in the radial direction is the maximum or the minimum is regulated, the accuracy of the outer diameter of the outer peripheral surface of the positioning cylindrical portion can be improved, and Variation can be suppressed.
[0033]
Furthermore, in the case of the manufacturing method of the wheel bearing unit according to the third and fourth aspects, the outer diameter of the outer peripheral surface reaches the target value during the turning process of the outer peripheral surface of the positioning cylindrical portion. The amount of turning after that can be confirmed. For this reason, it is possible to improve the accuracy of the outer diameter of the outer peripheral surface of the positioning cylindrical portion, and to suppress the variation in the outer diameter.
[0034]
Further, in the case of the manufacturing apparatus for a wheel bearing unit according to claims 5 to 6 and claim 8, the leakage of compressed air from the end of the compressed air passage opened to the holding surface of the support member is determined. Based on the confirmation, it can be confirmed whether or not the stationary wheel is correctly supported by the support member. That is, when the stationary wheel is correctly supported by the support member, the end of the compressed air passage opened to the holding surface of the support member is closed by the surface of the stationary wheel. Therefore, in this state, the amount of compressed air leakage from the end of the compressed air passage becomes zero or small. On the other hand, when the stationary wheel is not properly supported by the support member, the end of the compressed air passage opened to the holding surface of the support member is sufficiently closed by the surface of the stationary wheel. Disappears. Therefore, in this state, the amount of leakage of the compressed air from the end of the compressed air passage increases to some extent.
[0035]
For this reason, as described above, it is possible to confirm whether or not the stationary wheel is correctly supported by the support member based on the state of the leakage of the compressed air from the end of the compressed air passage. Therefore, according to the manufacturing apparatus of the wheel bearing unit described in claim 4, the stationary wheel is correctly supported by the support member (for example, the support member and the stationary wheel are supported in the supported state). Only when they are concentric, it is possible to make a choice to perform turning on the outer peripheral surface of the positioning cylinder portion and the outer peripheral surface of the rotating flange. If such a selection is made, not only the manufacturing method of the present invention but also the above-described manufacturing method of the preceding invention is adopted, the outer peripheral surface of the positioning cylinder portion after turning and the outer surface of the rotating flange are not used. The dimensional accuracy can be improved, and the dimensional variation can be suppressed.
[0036]
In the case of the manufacturing apparatus for a wheel bearing unit according to claims 7 and 8, when turning the outer peripheral surface of the positioning cylindrical portion and the outer surface of the rotating flange, cutting chips or the like generated due to the turning process. The movable cover can prevent the foreign matter from being scattered in the space axially inside the rotation-side flange. For this reason, it is possible to prevent the foreign matter from entering the space in which the plurality of rolling elements are installed, and to prevent the seal ring that closes both ends of the space from being damaged by the foreign matter. Also, since the movable cover is movable in the radial direction with respect to the outer peripheral surface of the rotating flange, if the movable cover is retracted radially outward, the wheel bearing unit can be supported by a chuck or the like. When attaching to and detaching from the member, the movable cover can be prevented from being in the way.
[0037]
Further, in the case of the manufacturing apparatus for a wheel bearing unit according to the ninth aspect, the number of the engaging projections provided on the outer peripheral surface of the distal end portion of the driving member is equal to the inner circumference of the spline hole provided at the center of the hub. Less than the number of the plurality of spline grooves formed on the surface. Therefore, the processing cost of the driving member can be reduced as compared with the case where the outer peripheral surface of the distal end portion of the driving member is a male spline portion that can be spline-engaged with the spline hole.
[0038]
BEST MODE FOR CARRYING OUT THE INVENTION
A first example of an embodiment of the present invention corresponding to claims 1 and 4 will be described with reference to FIGS. In the case of this example, as in the case of the prior invention shown in FIGS. 9 to 11 described above, first, the outer peripheral surface 17 of the positioning cylindrical portion 16 and the outer surface 27 of the rotating flange 15a constituting the hub main body 13a are subjected to turning. Prior to the application, the constituent members of the wheel bearing unit 5a are machined into predetermined shapes and dimensions except for the outer peripheral surface 17 of the positioning tubular portion 16 and the outer surface 27 of the rotating flange 15a. Further, the outer peripheral surface 17 of the positioning cylinder 16 and the outer surface 27 of the rotating flange 15a are processed into rough shapes and dimensions. Next, the components of the wheel bearing unit 5a are assembled in the state shown in FIG.
[0039]
Then, in this state, the wheel bearing unit 5a is assembled to a turning device 36 which is a manufacturing device. That is, as in the case of the above-described prior invention, as shown in FIG. 9, the outer peripheral surface 44 of the outer ring 6, which is a stationary wheel, near the inner end is gripped by the tip of the chuck 37 constituting the turning device 36. . At the same time, the male spline portion 42 provided on the outer peripheral surface of the distal end portion of the spindle 41, which is the driving member of the turning device 36, is spline-engaged with the spline hole 24 provided at the center of the hub body 13a. In the case of this example, the chuck 37 is rotatable around its own central axis.
[0040]
Next, while rotating the outer ring 6 by the chuck 37 and the hub body 13a by the spindle 41 in the same direction and at different rotational speeds, the outer peripheral surface 17 of the positioning cylinder 16 and the Three precision cutting tools 43a, 43b, 43c are abutted against both radial portions of the concave portion 39 of the outer side surface 27 of the rotating side flange 15a, and these portions are turned.
[0041]
In the case of this example, when performing the turning process as described above, the outer ring 6 rotates around the central axis of the chuck 37. On the other hand, the hub body 13a performs a composite rotation of rotation about its own central axis and rotation about the central axis of the chuck 37. In this case, if the chuck 37 and the outer ring 6 are concentric, the center axis of the chuck 37 coincides with the rotation center of the hub body 13a. (In other words, in this example, not only the hub body 13a but also the outer ring 6 are rotating), the outer peripheral surface 17 of the positioning cylinder 16 and the outer surface 27 of the rotating flange 15a. Can be finished to predetermined shapes and dimensions.
[0042]
On the other hand, the outer surface 6 of the outer ring 6 near the inner end of the outer ring 6 and the inner surface 45 of the fixed side flange 12, which serve as reference surfaces when the outer ring 6 is gripped by the chuck 37, respectively. When the center axes of the chuck 37 and the outer ring 6 are inclined with each other due to reasons such as poor concentricity or perpendicularity with respect to the center axis, the hub main body 13a rotates about its own center axis. While rotating, the chuck 37 swings around the central axis of the chuck 37. As a result, the outer peripheral surface 17 of the positioning cylinder 16 swings radially with the rotation, and the outer surface 27 of the rotating flange 15a swings axially with the rotation. Therefore, when the precision machining tools 43a, 43b, 43c are brought closer to the outer peripheral surface 17 of the positioning cylindrical portion 16 and the outer surface 27 of the rotary side flange 15a, the precision machining tools 43a, 43b, 43c become The outer peripheral surface 17 of the positioning cylindrical portion 16 and the outer surface 27 of the rotary side flange 15a abut on a portion where the deflection becomes maximum.
[0043]
Therefore, in the case of this example, of the outer peripheral surface 17 of the positioning tubular portion 16 and the outer surface 27 of the rotating flange 15a, the portions where the runout is maximum are used as a reference. Turning will be performed. That is, the cutting amount of each of the precision machining tools 43a, 43b, 43c is adjusted with reference to the portion of the outer peripheral surface 17 and the outer surface 27 where the runout is maximum, and the outer peripheral surface 17 and the outer surface 27 are adjusted. To a predetermined shape and dimensions. As a result, in the case of the present example, even when the center axis of the outer ring 6 (the rotation center of the hub body 13a) is inclined with respect to the center axis of the chuck 37, the dimensions of the outer peripheral surface 17 and the outer surface 27 are set. Accuracy can be improved, and variations in the dimensions can be suppressed.
[0044]
Next, a second example of the embodiment of the present invention corresponding to claims 2 and 4 will be described with reference to FIGS. In the case of this example, when turning is performed on the outer peripheral surface 17 of the positioning cylindrical portion 16 and the outer surface 27 of the rotating flange 15a, first, as shown in FIG. 44 is gripped by the tip of the chuck 37. Then, in this state, the outer ring 6 and the hub body 13a are rotated together with the chuck 37 based on the rolling resistance of the balls 21, 21. During this rotation, the phase in the circumferential direction of a portion where the deflection in the radial direction of the outer peripheral surface 17 of the positioning cylindrical portion 16 is maximum (or minimum) is detected. In the case of this example, while the outer ring 6 and the hub main body 13a are integrally rotated as described above, a detection rod (not shown) constituting a position detection device (not shown) is provided on a part of the outer peripheral surface 17 of the positioning tubular portion 16. Based on the fact that the tip of the measuring element is slid (or the measuring part of the non-contact type sensor is closely opposed), the radial deflection of the outer peripheral surface 17 of the positioning cylinder 16 becomes maximum (or minimum). Detect the circumferential phase of the part.
[0045]
After detecting the phase in the circumferential direction of the portion where the radial deflection of the outer peripheral surface 17 of the positioning cylindrical portion 16 is maximum (or minimum) as described above, the chuck 37 is then stopped to thereby stop the operation. With the outer ring 6 stationary, the male spline portion 42 of the spindle 41 is spline-engaged with the spline hole 24 of the hub body 13a. While the hub body 13a is being rotated by the spindle 41, the precision machining tool 43a is abutted against the outer peripheral surface 17 of the positioning cylinder 16 at the circumferential phase portion detected as described above. The surface 17 is turned. That is, in the case of the present example, the cutting amount of the precision machining tool 43a is adjusted based on a portion of the outer circumferential surface 17 of the positioning cylindrical portion 16 where the radial runout is maximum (or minimum). The outer peripheral surface 17 is finished to a predetermined shape and dimensions. As a result, in the case of this example, even when the center axis of the outer ring 6 (the rotation center of the hub body 13a) is inclined with respect to the center axis of the chuck 37, the dimensional accuracy of the outer peripheral surface 17 can be improved. And variations in the dimensions can be suppressed.
[0046]
Next, a third embodiment of the present invention corresponding to claims 3 and 4 will be described with reference to FIGS. Also in the case of this example, as in the case of the first example described above, when turning is performed on the outer peripheral surface 17 of the positioning cylindrical portion 16 and the outer surface 27 of the rotating flange 15a, first, as shown in FIG. The outer ring 6 is gripped by the tip of the chuck 37, and the male spline portion 42 of the spindle 41 is spline-engaged with the spline hole 24 of the hub body 13a.
[0047]
Then, while the outer ring 6 is stationary, the spindle body 41 is rotated by the spindle 41, while the precision machining tool 43 a is abutted against the outer peripheral surface 17 of the positioning cylinder 16, and the outer peripheral surface 17 is turned. Apply processing. In the case of the present example, by turning the outer peripheral surface 17 in this way, the outer peripheral surface 17 is processed into a cylindrical surface having an outer diameter larger than a target outer diameter. Thereafter, a dimensional difference between the outer diameter of the outer peripheral surface 17 and the target outer diameter is measured by a measuring device (not shown). Then, by turning the outer peripheral surface 17 of the positioning cylindrical portion 16 by the measured dimensional difference, the outer peripheral surface 17 is processed into the cylindrical surface having the target outer diameter. Also in the case of this example, even when the center axis of the outer ring 6 (the rotation center of the hub body 13a) is inclined with respect to the center axis of the chuck 37, the dimensional accuracy of the outer peripheral surface 17 can be improved. And variations in the dimensions can be suppressed.
[0048]
Next, FIGS. 1 to 3 show a fourth embodiment of the present invention corresponding to claims 5 to 9. The feature of this example lies in the structure of a turning device 36a, which is a device for manufacturing a wheel bearing unit. The structure of the wheel bearing unit 5 is the same as that of the wheel bearing unit 5 shown in FIG. 8 described above, and the manufacturing method is the same as that of the above-described prior invention or the first to third examples. Is the same as For this reason, the same reference numerals are given to the same parts, and the overlapping description will be omitted or simplified. Hereinafter, the description will focus on the characteristic parts of this example.
[0049]
In the case of the present example, compressed air passages 48a and 48b are provided inside each claw member 34a that constitutes the chuck 37a. The distal ends of the compressed air passages 48a and 48b are opened to the distal end inner peripheral surface 46 and the distal end surface 47 of the claw members 34a, respectively, which are holding surfaces. Compressed air can be freely supplied into the compressed air passages 48a and 48b from the base ends (the right ends in FIG. 1) of the compressed air passages 48a and 48b. Further, the air pressure in each of the compressed air passages 48a, 48b can be detected by a pressure sensor (not shown) provided on the base end side of each of the compressed air passages 48a, 48b.
[0050]
Also in the case of this example, when the outer ring 6 is gripped by the chuck 37a as described above, the inner end portion of the outer ring 6 is attached to the inner diameter side portion of the claw member 34a displaced radially outward. Is inserted, these claw members 34a are displaced radially inward. Thereby, as shown in FIG. 1, the distal end inner peripheral surface 46 of each of the claw members 34 a is brought into contact with the outer peripheral surface 44 of the portion near the inner end of the outer ring 6, and the distal end surface 47 is similarly fixed to the fixed side flange 12. It is in a state where it abuts against the inner side surface 45.
[0051]
Further, in this state, the outer ring 6, which serves as a reference surface when the outer ring 6 is gripped by the chuck 37a, and the outer ring 44 of the inner surface 45 of the portion near the inner end of the outer ring 6 and the inner surface 45 of the fixed side flange 12. If the concentricity or the perpendicularity of the outer ring 6 to the center axis of the outer ring 6 is good and the outer ring 6 is properly held by the chuck 37a, the chuck 37a and the outer ring 6 are concentric. Between the distal end inner peripheral surface 46 of each claw member 34a and the outer peripheral surface 44 near the inner end of the outer ring 6, and between the distal end surface 47 of each claw member 34a and the inner side surface 45 of the fixed side flange 12. Then, there is almost no gap in each case. Therefore, in this case, each of the compressed air passages 48a and 48b having the distal end portion opened at the distal end inner peripheral surface 46 and the distal end surface 47 of each of the claw members 34a is provided with the compressed air passage 48a. , 48b, the compressed air hardly leaks from the distal openings of the compressed air passages 48a, 48b.
[0052]
On the other hand, the concentricity or the perpendicularity of the outer peripheral surface 44 of the portion near the inner end of the outer ring 6 and the inner side surface 45 of the fixed side flange 12 with respect to the center axis of the outer ring 6 is not good or good. Even if the chuck 37a does not hold the outer race 6 correctly, if the center axes of the chuck 37a and the outer race 6 are inclined with respect to each other, the inner circumferential surface 46 of the distal end of each claw member 34a is Between at least one of between the outer peripheral surface 44 near the inner end of the outer ring 6 and between the distal end surface 47 of each claw member 34a and the inner side surface 45 of the fixed side flange 12, or Gaps occur. Therefore, in this case, each of the compressed air passages 48a and 48b having the distal end portion opened at the distal end inner peripheral surface 46 and the distal end surface 47 of each of the claw members 34a is provided with the compressed air passage 48a. , 48b, compressed air is leaked from the distal end opening of at least one of the compressed air passages 48a (48b) according to the gap. In the case of this example, the degree to which the compressed air leaks from the distal end openings of the compressed air passages 48a and 48b is determined by measuring the air pressure in the compressed air passages 48a and 48b by the pressure sensor (not shown). You can check.
[0053]
Therefore, in the case of this example, if the degree to which the compressed air leaks from the distal end openings of the compressed air passages 48a and 48b is confirmed by the pressure sensor while the outer ring 6 is gripped by the chuck 37a, the chuck 37a Thus, it can be confirmed whether or not the outer ring 6 is gripped in a correct posture (the chuck 37a and the outer ring 6 are concentric). In the case of this example, only when it is confirmed that the outer ring 6 is gripped in the correct posture by the chuck 37a, the outer peripheral surface 17 of the positioning cylindrical portion 16 and the outer Perform turning. For this reason, in the case of this example, not only the manufacturing method of the first to third examples described above but also the case where the manufacturing method according to the above-described invention is adopted, the outer peripheral surface of the positioning cylindrical portion 16 after the turning is performed. 17 and the outer side surface 27 of the rotary side flange 15 can have good dimensional accuracy, and this dimensional variation can be suppressed.
[0054]
Further, in the case of this example, the outer peripheral surface of the distal end portion 55 of the spindle 41a for driving the hub body 13 to rotate is not a male spline portion. In the case of the present example, the number of the plurality of spline grooves 49 formed in the outer peripheral surface of the tip portion 55 of the spindle 41a and the inner peripheral surface of the spline hole 24 provided in the center of the hub body 13 (this example) In this case, a plurality of (four in this example) engagement projections 50, 50 less than twelve are provided at equal intervals in the axial direction of the spindle 41a in the circumferential direction. ing. The engaging projections 50 are freely engageable with the spline grooves 49. That is, in the case of the present example, the shape of the outer peripheral surface of the distal end portion 55 of the spindle 41a is such that the number of spline projections constituting the male spline portion capable of being spline-engaged with the spline hole 24 is smaller than the original number. The shape is as follows. By making the outer peripheral surface of the distal end portion 55 of the spindle 41a have the shape described above, the processing cost of the outer peripheral surface of the distal end portion 55 is reduced. In the case of the present example, the distal end 55 of the spindle 41a provided with the engaging projections 50, 50 is detachably attached to the base end portion 56 of the spindle 41a. The portion 55 can be replaced with a tip of another size (or another shape).
[0055]
The operation of engaging the engaging projections 50, 50 with the spline grooves 49, 49 is performed by gripping the outer ring 6 with the chuck 37a and then inserting the tip of the spindle 41a inside the spline hole 24. This is performed based on the insertion of the part 55 from the outer end opening of the spline hole 24. Therefore, when the distal end portion 55 of the spindle 41a is inserted into the spline hole 24 in this manner, the phases of the engaging projections 50, 50 and the spline grooves 49, 49 in the circumferential direction are matched. Need to be kept. This phase adjustment can be performed based on rotating at least one of the spindle 41a and the hub body 13 after gripping the outer ring 6 with the chuck 37a. However, if the above-described phase adjustment is performed after the outer ring 6 is gripped by the chuck 37a, the efficiency of the manufacturing operation of the wheel bearing unit 5 is reduced.
[0056]
Therefore, in the case of this example, before the outer ring 6 is gripped by the chuck 37a, the circumferential phase of each of the spline grooves 49 is adjusted to a predetermined direction. In this manner, the operation of adjusting the circumferential phase of each spline groove 49, 49 to a predetermined direction is performed, for example, by inserting a spline shaft having the circumferential phase adjusted to the predetermined direction into the spline hole 24. Perform based on insertion. Then, after the phases of the spline grooves 49, 49 are adjusted in a predetermined direction, the wheel bearing unit 5 is transported to the chuck 37a while keeping the phase from shifting, and the chuck 37a is used to transfer the wheel bearing unit 5 to the chuck 37a. The outer ring 6 is gripped. Then, with the outer ring 6 held by the chuck 37a in this manner, the circumferential phase of each of the spline grooves 49, 49 matches the circumferential phase of each of the engaging projections 50, 50. ing. Thus, in the case of this example, after the outer ring 6 is gripped by the chuck 37a, the tip end portion 55 of the spindle 41a can be immediately inserted into the spline hole 24, thereby manufacturing the wheel bearing unit 5. Improves work efficiency.
[0057]
If the distal end 55 of the spindle 41a can be slightly displaced with respect to the base end portion 56 of the spindle 41a, the center axis of the distal end 55 of the spindle 41a and the spline hole 24 can be adjusted. Even when they are slightly displaced from each other, the tip portion 55 of the spindle 41a can be inserted inside the spline hole 24.
[0058]
Further, in the case of this example, in a state where the outer ring 6 is gripped by the chuck 37a, a portion surrounding the upper side and both sides of the wheel bearing unit 5 is fixed to the turning device 36a and does not move. A fixed cover 51 is provided, and a movable cover 52 is provided in a portion adjacent to the front (left side in FIG. 1) of the fixed cover 51. The movable cover 52 is located above the rotating side flange 15 in a state where the outer ring 6 is gripped by the chuck 37a, and is movable vertically. Further, the inner peripheral surface 53 of the movable cover 52 is formed in an arc shape that can freely approach the upper and both sides of the outer peripheral surface of the rotating side flange 15 in a state where the movable cover 52 is displaced downward. I have. Further, a flange 54 is provided at an inner end of an inner peripheral surface 53 of the movable cover 52. Then, in a state where the inner peripheral surface 53 is in close proximity to the outer peripheral surface of the rotating flange 15, the side surface of the flange 54 is in proximity to the outer radial half of the inner surface of the rotating flange 15. I have to.
[0059]
In the case of this example, when attaching and detaching the wheel bearing unit 5 to and from the turning device 36a, the movable cover 52 is retracted upward so as not to hinder the attaching / detaching operation. On the other hand, when turning the outer peripheral surface 17 of the positioning cylindrical portion 16 and the outer surface 27 of the rotating flange 15, the movable cover 52 is displaced downward, as shown in FIGS. In this way, the inner peripheral surface 53 of the movable cover 52 is made to approach and approach the upper part and both side parts of the outer peripheral surface of the rotating side flange 15, and the side surface of the flange 54 provided at the inner end of the inner peripheral surface 53. The inner surface of the rotation side flange 15 is closely opposed to the outer diameter side portion. When turning the outer peripheral surface 17 of the positioning cylindrical portion 16 and the outer surface 27 of the rotating flange 15, foreign matter such as cutting powder generated along with the turning is located inside the rotating flange 15 in the axial direction. It is prevented by the movable cover 52 and the fixed cover 51 from flying into the space.
[0060]
In the case of this example, the above-mentioned turning is performed in a state where the studs 9 (see FIGS. 8 and 9) are not inserted into the mounting holes 29 and 29 provided in the rotating side flange 15. Spaces on both sides in the axial direction of the rotating side flange 15 communicate with each other through the mounting holes 29, 29. For this reason, in the case of the present example, at the time of the above-described turning, the foreign matter such as the swarf is prevented from entering the space inside the rotating side flange 15 in the axial direction through the mounting holes 29 and 29. Therefore, the compressed air flows from the inside in the axial direction of the rotating side flange 15 to the outside in the axial direction in the mounting holes 29. In the case of this example, the movable cover 52 is provided only above the rotating flange 15, but such a movable cover is provided on both upper and lower sides of the rotating flange 15 (both sides sandwiching the center axis). It can also be provided.
[0061]
In the present invention, the manufacturing method of the wheel bearing unit according to claims 1 to 3 and the manufacturing apparatus of the wheel bearing unit according to claims 5 and 7 are as shown in FIG. The present invention is also applicable to the wheel bearing unit 5b in which the stationary wheel is the inner ring 57. Although the wheel bearing units 5 and 5a described above are for rotatably supporting the drive wheels (the front wheels of the FF vehicle, the rear wheels of the FR vehicle, and all the wheels of the 4WD vehicle) with respect to the suspension device. On the other hand, the wheel bearing unit 5b shown in FIG. 4 is for rotatably supporting a driven wheel (rear wheel of an FF vehicle, front wheel of an FR vehicle) with respect to a suspension device.
[0062]
Such a wheel bearing unit 5b shown in FIG. 4 includes a cylindrical hub 58, a pair of short cylindrical inner rings 57, 57 each of which is a stationary wheel, and a plurality of balls 21, 21. Is provided. The hub 58 is provided with a rotating flange 15 at a portion near the outer end of the outer peripheral surface and a positioning cylindrical portion 16 at the outer end surface, and a double row of outer races at a middle portion or a portion near the inner end of the inner peripheral surface. Tracks 59, 59 are formed. Each of the inner races 57, 57 has an inner raceway 60 formed on the outer peripheral surface thereof, and is disposed concentrically with the hub 58 on the inner diameter side portion of the hub 58 in a state where the axial end surfaces thereof abut each other. are doing. A plurality of the balls 21 are provided between the outer raceways 59, 59 and the inner raceways 60, 60, respectively, so as to freely roll. When such a wheel bearing unit 5b is used, each of the inner rings 57, 57 is externally fitted and fixed to a fixed shaft constituting a suspension device, and the wheels and the brake rotating body that are externally fitted to the positioning cylinder 16 are attached to the above-mentioned position. A plurality of studs 9 and a nut (not shown) are connected and fixed to the rotation side flange 15.
[0063]
In order to apply the present invention to the above-described wheel bearing unit 5b, when turning the outer peripheral surface 17 of the positioning cylindrical portion 16 and the outer surface 27 of the rotating flange 15, the inner ring is used. 57 and 57 are supported by a support member, and a drive member is engaged with a part of the hub. In this case, as the support member, for example, a shaft member that can freely fit and support the inner rings 57 and 57 can be adopted. Further, as the driving member, for example, a chuck capable of gripping the outer peripheral surface of the hub 58 can be employed.
[0064]
The manufacturing method of the wheel bearing unit according to the first to third aspects and the manufacturing apparatus of the wheel bearing unit according to the fifth and seventh aspects are applied to the wheel bearing unit 5c as shown in FIG. Is also applicable. FIGS. 5 to 7 show, as a fifth example of the embodiment of the present invention, situations where the inventions of claims 1 to 3, 5 and 7 are applied to such a wheel bearing unit 5c. . The wheel bearing unit 5c of this example is for supporting a driven wheel rotatably with respect to a suspension device. Such a wheel bearing unit 5c has substantially the same structure as that of the driving wheel wheel bearing unit 5a shown in FIG. 9 described above, but is used for a driven wheel, so that the hub body 13b constituting the hub 8b is formed. Has no spline hole in the center. Therefore, in the case of this example, a part of the hub body 13b is provided instead of the spline hole so that the tip end of the spindle 41b as the driving member can be engaged with the hub body 13b. Therefore, it is necessary to provide an engaged portion.
[0065]
Therefore, in the case of the present example, of the inner peripheral surface of the outer end portion of the hub main body 13b, at a portion located radially inward of the rotating flange 15a, at two positions on the opposite sides in the circumferential direction, The engaged convex portions 61 are formed respectively. At the same time, engaging projections 62, 62 are formed in the axial direction at two positions on the outer peripheral surface of the spindle 41b, which are opposite to each other in the circumferential direction. Then, as shown in FIG. 5, the tip of the spindle 41b is inserted into the inner diameter side portion of the outer end of the hub body 13b, so that the engagement projections 61 The distal ends of 62 and 62 are freely engageable in a state where their side surfaces are in contact with each other in the circumferential direction. By engaging in this manner, the hub 8b is rotatably driven by the spindle 41b.
[0066]
Turning to the outer peripheral surface 17 of the positioning tubular portion 16 and the outer peripheral surface 27 of the rotating flange 15a, in order to carry out the inventions of claims 1 to 3, 5 and 7 for the wheel bearing unit 5c as described above. At the time of application, as shown in FIG. 5, the inner end of the outer race 6 is gripped by the chuck 37b. For this reason, in the case of the present embodiment, the inner peripheral surfaces of the claw members 34b, 34b constituting the chuck 37b are brought into close contact with the outer peripheral surface 44 of the inner end of the outer ring 6, and the respective claw members 34b , 34b abuts against the inner surface 45 of the fixed flange 12 of the outer race 6 with the distal ends (left ends in FIG. 5) of the flanges 63, 63 provided on the outer peripheral surface near the radial inner end. At the same time, the tips of the engaging projections 62, 62 constituting the spindle 41b are engaged with the engaged projections 61, 61 provided on the inner peripheral surface of the outer end of the hub body 13b, The hub 8b is rotatably driven. Other configurations and operations are the same as those in the above-described embodiments corresponding to claims 1 to 3, 5 and 7.
[0067]
When the invention described in claims 1 to 3, 5 and 7 is applied to a wheel bearing unit including a solid-state hub as in the fifth example described above, the hub body and the drive member are connected to each other. The structure of the engaging portion is not limited to the fifth example shown in FIGS. In particular, various structures can be adopted for the structure of the engaged portion provided on the hub body as long as the strength of the hub body is not impaired or the surrounding functions are not impaired.
[0068]
【The invention's effect】
Since the manufacturing method and the manufacturing apparatus of the wheel bearing unit of the present invention are configured and operated as described above, the dimensional accuracy of the outer peripheral surface of the positioning cylinder portion and the outer surface of the rotating flange can be improved, and This dimensional variation can be suppressed. In addition, cost reduction and function improvement of the manufacturing apparatus can be achieved.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a fourth example of an embodiment of the present invention.
FIG. 2 is an enlarged sectional view taken on line AA of FIG. 1;
FIG. 3 is a view seen from the left side of FIG. 1;
FIG. 4 is a cross-sectional view showing another example of a wheel bearing unit to which the present invention can be applied.
FIG. 5 is a sectional view showing a fifth example of the embodiment of the present invention.
FIG. 6 is a cross-sectional view of the hub shown in FIG.
FIG. 7 is a cross-sectional view of the drive member shown in FIG.
FIG. 8 is a sectional view showing an example of an assembled state of the wheel bearing unit to which the present invention is applied.
FIG. 9 shows an example of the first embodiment of the present invention and first to third examples of the embodiment of the present invention in a state in which turning is performed on the outer peripheral surface of the positioning cylinder and the outer surface of the rotary flange. FIG.
FIG. 10 is a partially enlarged sectional view of FIG. 9;
FIG. 11 is a view of the hub viewed from the left in FIG. 9 omitting a spindle for rotationally driving the hub.
FIG. 12 is an exaggerated cross-sectional view showing a state where the rotation center of the hub is inclined with respect to the center axis of the chuck constituting the turning apparatus.
[Explanation of symbols]
1 wheel
2 rotor
3 Knuckles
4 Support holes
5,5a, 5b, 5c Wheel bearing unit
6 Outer ring
7 volts
8, 8a, 8b hub
9 studs
10 nuts
11a, 11b Outer ring track
12 Fixed side flange
13, 13a, 13b Hub body
14 Inner ring
15, 15a Rotating flange
16 Positioning tube
17 Outer peripheral surface
18 First inner ring track
19 small diameter step
20 Second inner ring track
21 balls
22 cage
23a, 23b Seal ring
24 spline holes
25 constant velocity joint
26 spline shaft
27 Outside surface
28 Caulking part
29 mounting holes
30 Large diameter part
31 Small diameter part
32 steps
33 Interior Space
34, 34a, 34b claw members
35 Housing part
36,36a Turning equipment
37, 37a, 37b Chuck
38 Protective material
39 recess
41, 41a, 41b spindle
42 Male spline section
43a, 43b, 43c Precision machining tool
44 Outer surface
45 Inside
46 Inner surface
47 Tip surface
48a, 48b compressed air passage
49 spline groove
50 engaging projection
51 Fixed cover
52 Movable cover
53 Inner circumference
54 Tsubabe
55 Tip
56 Proximal side
57 Inner ring
58 Hub
59 Outer ring track
60 Inner ring track
61 Engagement convex
62 engaging projection
63 Flange

Claims

A stationary wheel that has a double row stationary side track on the stationary side peripheral surface and does not rotate while being supported by the suspension device during use, and a rotating side flange near the outer end of the outer peripheral surface, the stationary side peripheral surface and Hubs each having a double-row rotating-side track facing each of the stationary-side tracks on the opposed rotating-side peripheral surface, and a positioning cylinder portion on the outer end face, and each of the stationary-side tracks and each of the rotating-side tracks. A method for manufacturing a bearing unit for a wheel, comprising: a plurality of rolling elements provided in such a manner that each of the rolling elements is rotatably provided between at least the stationary wheel, the hub, and the rolling elements. By supporting the stationary wheel by the support member and engaging the drive member with a part of the hub, the support member and the drive member are rotated at different rotational speeds about their own central axes. The above stationary wheel and above By rotating at least one of the outer peripheral surface of the positioning cylindrical portion and the outer peripheral surface of the rotating flange while rotating the bearings at mutually different rotational speeds, the surface is formed into a predetermined shape. And a method of manufacturing a wheel bearing unit to be processed into dimensions.

A stationary wheel that has a double row stationary side track on the stationary side peripheral surface and does not rotate while being supported by the suspension device during use, and a rotating side flange near the outer end of the outer peripheral surface, the stationary side peripheral surface and Hubs each having a double-row rotating-side track facing each of the stationary-side tracks on the opposed rotating-side peripheral surface, and a positioning cylinder portion on the outer end face, and each of the stationary-side tracks and each of the rotating-side tracks. A method for manufacturing a bearing unit for a wheel, comprising: a plurality of rolling elements provided in such a manner that each of the rolling elements is rotatably provided between at least the stationary wheel, the hub, and the rolling elements. In a state where the stationary wheel is supported by the support member, first, by rotating the support member about its own central axis, the stationary wheel and the hub are both rotated about the central axis of the support member, During this rotation, the positioning cylinder Detecting the phase in the circumferential direction of the portion where the radial deflection of the outer peripheral surface of the outer peripheral surface is the maximum or the minimum, and then the stationary wheel is stopped by stopping the support member, and the hub is connected to the hub. While rotating by a driving member engaged with a part of the outer peripheral surface of the positioning cylindrical portion, based on abutting a cutting tool on a portion corresponding to the detected phase in the circumferential direction, based on the outer peripheral surface, A method for manufacturing a bearing unit for a wheel, in which the outer peripheral surface of the positioning cylindrical portion is processed into a predetermined shape and dimensions by performing turning.

A stationary wheel that has a double row stationary side track on the stationary side peripheral surface and does not rotate while being supported by the suspension device during use, and a rotating side flange near the outer end of the outer peripheral surface, the stationary side peripheral surface and Hubs each having a double-row rotating-side track facing each of the stationary-side tracks on the opposed rotating-side peripheral surface, and a positioning cylinder portion on the outer end face, and each of the stationary-side tracks and each of the rotating-side tracks. A method for manufacturing a bearing unit for a wheel, comprising: a plurality of rolling elements provided in such a manner that each of the rolling elements is rotatably provided between at least the stationary wheel, the hub, and the rolling elements. While the stationary wheel is supported by the support member, the hub is rotated by a driving member engaged with a part of the hub, and the outer peripheral surface of the positioning cylindrical portion is subjected to turning to thereby remove the outer peripheral surface. , A larger outer diameter than the target After processing into the outer peripheral surface shape, the dimensional difference between the outer diameter of the outer peripheral surface and the target outer diameter is measured, and the outer peripheral surface of the positioning cylindrical portion is further turned by the measured dimensional difference. Accordingly, a method of manufacturing a bearing unit for a wheel, in which the outer peripheral surface of the positioning cylindrical portion is processed into a peripheral surface shape having the target outer diameter.

The method for manufacturing a bearing unit for a wheel according to any one of claims 1 to 3, wherein the stationary wheel is an outer ring arranged radially outward of the hub.

A stationary wheel that has a double row stationary side track on the stationary side peripheral surface and does not rotate while being supported by the suspension device during use, and a rotating side flange near the outer end of the outer peripheral surface, the stationary side peripheral surface and Hubs each having a double-row rotating-side track facing each of the stationary-side tracks on the opposed rotating-side peripheral surface, and a positioning cylinder portion on the outer end face, and each of the stationary-side tracks and each of the rotating-side tracks. A wheel bearing unit having a plurality of rolling elements provided so as to be able to freely roll, respectively, a support member capable of supporting the stationary wheel, and a state in which the stationary wheel is engaged with a part of the hub. An apparatus for manufacturing a bearing unit for a wheel, comprising: a driving member rotatably driving the hub; wherein a compressed air passage is provided inside the support member, and a downstream end of the compressed air passage is supported by the support member. On the surface of the member, the static Apparatus for manufacturing a wheel bearing unit which is opened in the clamping surfaces is part to abut on the surface of the stationary ring in supporting wheel.

6. The manufacturing apparatus for a wheel bearing unit according to claim 5, wherein the stationary wheel is an outer ring arranged so as to surround the hub, and the support member is a chuck capable of gripping an outer peripheral surface of the outer ring.

A stationary wheel that has a double row stationary side track on the stationary side peripheral surface and does not rotate while being supported by the suspension device during use, and a rotating side flange near the outer end of the outer peripheral surface, the stationary side peripheral surface and Hubs each having a double-row rotating-side track facing each of the stationary-side tracks on the opposed rotating-side peripheral surface, and a positioning cylinder portion on the outer end face, and each of the stationary-side tracks and each of the rotating-side tracks. A wheel bearing unit having a plurality of rolling elements provided so as to be able to freely roll, respectively, a support member capable of supporting the stationary wheel, and a state in which the stationary wheel is engaged with a part of the hub. An apparatus for manufacturing a bearing unit for a wheel, comprising a driving member capable of rotating and driving the hub, and after assembling at least the stationary wheel, the hub, and the rolling elements, the stationary wheel is moved by the support member. In the state where it is supported, Apparatus for manufacturing a wheel bearing unit is provided with the perspective movably movable cover in a radial direction relative to the circumferential surface.

The manufacturing apparatus for a wheel bearing unit according to claim 5 or 7, wherein the stationary wheel is an outer ring disposed radially outward of the hub.

An outer ring that has a double-row outer ring raceway on the inner peripheral surface and does not rotate in a state of being supported by the suspension device during use, and a rotation side flange near the outer end of the outer peripheral surface, and a middle portion or a portion near the inner end similarly. A double-row inner raceway, a positioning cylindrical portion on the outer end surface, a hub having a spline hole at the center, and a plurality of rolls respectively provided between the outer raceways and the inner raceways are provided between the hubs. A wheel bearing unit having a rolling element and a supporting member capable of supporting the outer ring, and a driving member capable of rotating and driving the hub while being engaged with a part of the hub. The drive member is provided on an outer peripheral surface of a tip end which can be inserted into the spline hole, and is provided with a plurality of spline grooves formed on an inner peripheral surface of the spline hole. The mating projections are divided by the number of these spline grooves. Remote apparatus for manufacturing a wheel bearing unit in which has only a small number.