JP4193353B2

JP4193353B2 - Axle bearing device and manufacturing method thereof

Info

Publication number: JP4193353B2
Application number: JP2000359578A
Authority: JP
Inventors: 一寿戸田; 照之脇阪; 信一郎柏木; 匡御手洗
Original assignee: JTEKT Corp
Current assignee: JTEKT Corp
Priority date: 2000-11-27
Filing date: 2000-11-27
Publication date: 2008-12-10
Anticipated expiration: 2020-11-27
Also published as: JP2002161924A

Description

【０００１】
【発明の属する技術分野】
本発明は、車軸用軸受装置およびその製造方法に関する。この車軸用軸受装置としては、例えば自動車のハブユニットなどが挙げられる。
【０００２】
【従来の技術】
従来の車軸用軸受装置の一例として、米国特許５４９０７３２があり、図６および図７に示すような構成になっている。
【０００３】
図中、８０はハブホイール、８１は複列外向きアンギュラ玉軸受などの複列転がり軸受、８２はかしめ部である。
【０００４】
ハブホイール８０の自由端をローリングかしめにより径方向外向きに屈曲させて、複列転がり軸受８１の内輪８３の端面に対してかしめ付けることによって、ハブホイール８０に複列転がり軸受８１を抜け止め固定している。
【０００５】
なお、かしめ部８２の外端面の全体形状は、丸みを帯びた曲面形状になっている。しかも、かしめ部８２の内径側角部の曲率半径Ｒは、内輪８３の内周面角部における円弧状のいわゆるＲ面取りの曲率半径ｒよりも大きく設定している。
【０００６】
【発明が解決しようとする課題】
上記従来例において、ハブホイール８０の自由端を所定以上の肉厚ｄ１に厚くできる場合には、図８の仮想線で示すように、かしめ部８２の内径側角部の肉厚を厚く維持できるので、問題ないが、ハブホイール８０の自由端を所定未満の肉厚ｄ２に薄くしなければならない場合には、図８の実線で示すように、かしめ部８２の内径側角部が引き延ばされる形態で塑性変形されて肉厚が薄くなりすぎるとともに、曲率半径Ｒが大きくなり過ぎるために、かしめ部８２そのものの剛性が不足する結果になりやすい。そのため、かしめにより複列転がり軸受８１に付与した軸力の反力によってかしめ部８２が倒れて内輪８３の端面から離れてしまうなど、複列転がり軸受８１に作用する抜け荷重に対する抗力つまり抜け抗力が不足する。
【０００７】
このような事情に鑑み、本発明は、車軸用軸受装置において、かしめ部による抜け抗力を向上させることを目的とする。
【０００８】
【課題を解決するための手段】
本発明第１の車軸用軸受装置は、内輪内径角部にＲ面取りを設けた転がり軸受が外嵌装着される軸体の自由端側円筒部をかしめ治具によってローリングかしめすることにより径方向外向きに屈曲させて前記転がり軸受の内輪の前記Ｒ面取りに沿ってかしめ付けることにより軸体に転がり軸受を抜け止め固定したもので、前記かしめ部の内径側角部が、前記かしめ治具に形成された傾斜面によって軸方向外向きに漸次拡径する円錐形状に形成されており、この円錐面の最小径位置が、内輪端面よりも軸方向外側に配置され、この円錐面の最大径位置が、内輪内周面よりも径方向内側に配置されている、ことを特徴としている。
上記第１の構成において、前記かしめ部は、前記円錐面の外径側に、前記かしめ治具に形成された平坦部によって径方向に沿う平坦面が形成されていることが望ましい。さらに、前記かしめ部の外径側に、前記かしめ治具に形成された傾斜面によって内輪側に傾斜する傾斜面が形成されていることが望ましい。
【０００９】
本発明第２の車軸用軸受装置は、上記第１の構成において、前記円錐面と軸体中心線とでなす角度が、２０〜８０度の範囲に設定されている、ことを特徴としている。
【００１０】
本発明第３の車軸用軸受装置は、上記第１または第２の構成において、前記円錐面における最小径側のコーナーと最大径側のコーナーが、それぞれ曲面形状とされ、この曲面が前記内輪の内径側角部における面取りの曲率半径よりも小さな曲率半径に設定されている、ことを特徴としている。
【００１１】
要するに、本発明では、かしめ部の内径側角部を曲面とせずに円錐面としている。このような形状とする場合、軸体の自由端を屈曲させるかしめ過程において、内径側角部が引き延ばされる形態に塑性変形せずに済んだことを意味しており、肉厚つまりかしめ部の円錐面と内輪の内径側角部との間の厚みがかしめ前とほぼ同等に維持できるようになる。そのため、かしめ部の剛性が向上して、かしめ後にかしめ部が倒れて内輪の端面から離れることが抑制される。
【００１２】
特に、第２の構成のように、かしめ部に設けた円錐面の傾斜角度を所要範囲内に規定すれば、内径側角部の肉厚つまりかしめ部の円錐面と内輪の内径側角部との間の厚みを可及的に大きくするうえで有利となる。
【００１３】
また、第３の構成のように、かしめ部における円錐面の端部を曲面形状とすれば、かしめ過程においてかしめ部の局部に過大な応力が作用せずに済み、微小亀裂などの発生が回避される。
なお、本発明の車軸用軸受装置の製造方法は、かしめ部の内径側角部を、ローリングかしめ用のかしめ治具に形成された傾斜面によって軸方向外向きに漸次拡径する円錐形状に形成し、この円錐面の最小径位置が、内輪端面よりも軸方向外側に配置され、この円錐面の最大径位置が、内輪内周面よりも径方向内側に配置されている、ことを特徴とする。
前記かしめ治具としては、先端面の中心部に凸部が形成され、凸部の外周に環状陥没部が形成され、環状陥没部の内径側に前記傾斜面が形成されているものを用いる。
【００１４】
【発明の実施の形態】
本発明の詳細を図面に示す実施形態に基づいて説明する。ここでは、車軸用軸受装置として、自動車の駆動輪に用いられるタイプのハブユニットを例に挙げている。
【００１５】
図１ないし図４に本発明の一実施形態を示している。図１は、車軸用軸受装置を示す縦断面図、図２は、かしめ部の拡大図、図３は、図１のかしめ部を得るためのかしめ治具の縦断面図、図４は、図３のかしめ治具を用いたローリングかしめ形態を示す説明図である。
【００１６】
図例の車軸用軸受装置は、ハブホイール１と、複列転がり軸受２と、等速ジョイント３とを備えている。
【００１７】
ハブホイール１は、中空構造となっており、その外周面の軸方向中間部には径方向外向きのフランジ１１が形成され、また、中空孔の所要領域にはスプライン（図示省略）が形成され、外周面においてフランジ１１よりも車両インナ側には複列転がり軸受２における車両アウタ側の玉２２群の軌道面１２が形成された構成となっている。
【００１８】
複列転がり軸受２は、二列の軌道溝を有する単一の外輪２１と、二列で配設される転動体としての複数の玉２２と、二つの冠形保持器２３と、車両インナ側の玉２２群に関する内輪２４とから構成された複列外向きアンギュラ玉軸受とされており、車両アウタ側の玉２２群の内輪については上述したようにハブホイール１の軌道面を利用しているため存在しない。
【００１９】
等速ジョイント３は、周知のツェッパタイプ（バーフィールド型）等速ジョイントと呼ばれるものとされ、外輪３１、内輪３２、玉３３および保持器３４などから構成されている。外輪３１は、内輪３２、玉３３および保持器３４などが収納配設される椀形部３５と、この椀形部３５の小径側に一体に連接される軸部３６とから構成されている。軸部３６の外周面には、スプラインが形成されており、ハブホイール１の中空孔に対してスプライン嵌合される。
【００２０】
そして、ハブホイール１のフランジ１１に対して図示しないディスクブレーキ装置のディスクロータおよび車輪があてがわれて複数のボルト１３により装着される。また、複列転がり軸受２の外輪２１に設けてある径方向外向きのフランジ２５が、図示しない車体などにボルト止めされる。さらに、等速ジョイント３の内輪３２に対してシャフト５がスプライン嵌合されて止め輪（符号省略）などで抜け止め固定される。前述のシャフト５の他端側は、図示しない別の等速ジョイントを介して車両のデファレンシャル装置に取り付けられる。
【００２１】
このような車軸用軸受装置では、シャフト５の回転動力が、等速ジョイント３を介してハブホイール１に取り付けられてある車輪（図示省略）に対して伝達される。
【００２２】
なお、上記ハブホイール１の外周面に複列転がり軸受２が取り付けられる。このハブホイール１の車両インナ側端部は、径方向外向きに屈曲されて、複列転がり軸受２の内輪２４における内周面角部のＲ面取り２４ａから車両インナ側端面に対してかしめつけられている。このかしめ部には、符号１４を付してある。
【００２３】
また、ハブホイール１に対して等速ジョイント３が複列転がり軸受２の近傍に隣り合わされる形態で結合されている。つまり、ハブホイール１の中空孔において、軸方向中間領域のみにスプラインが形成され、車両インナ側領域と車両アウタ側領域とが軸方向中間領域のスプラインにおける溝底の直径よりも拡径された円筒面に形成されている。この車両インナ側の拡径領域に符号１５を、また、車両アウタ側の拡径領域に符号１６をそれぞれ付してある。また、等速ジョイント３の外輪３１における軸部３６の端縁側には、周溝３７が設けられている。この周溝３７に対してＣ形止め輪６が一部突出する状態で嵌入されている。そして、ハブホイール１の中空孔に対して等速ジョイント３の外輪３１における軸部３６を車両インナ側からスプライン嵌合させるのであるが、軸部３６のスプラインの車両インナ側エンド部がハブホイール１のスプラインの車両インナ側エンド部に対して当接すると、軸部３６に装着してあるＣ形止め輪６が中空孔における車両アウタ側の拡径領域１６にまで到達し、Ｃ形止め輪６が径方向外向きに拡がり、拡径領域に対して当接する状態になる。これで、ハブホイール１のスプラインが、その軸方向両側から軸部３６のスプラインにおける車両インナ側端縁とＣ形止め輪６とにより挟まれた形態となり、ハブホイール１に対して等速ジョイント３が非分離に結合された状態になる。
【００２４】
なお、この状態では、かしめ部１４と等速ジョイント３の外輪３１における椀形部３５との間に所要の隙間が形成されるように管理されていて、かしめ部１４に対してかしめ時に付与した軸力以外の負荷が全く作用しないようになっている。なお、かしめ部１４に対して等速ジョイント３の椀形部３５を突き当てて前記隙間を無くすようにしてもよい。
【００２５】
この実施形態では、ハブホイール１のかしめ部１４の形状に特徴があるので、以下で説明する。
【００２６】
つまり、図２に示すように、かしめ部１４の内径側角部は、車両インナ側に向けて漸次拡径する円錐面１４ａに形成されている。この円錐面１４ａにおいて最小径の位置は、複列転がり軸受２の内輪２４の端面に沿う垂線ｇよりも車両インナ側に配置されている。
【００２７】
そして、上記円錐面１４ａとハブホイール１の中心軸線Ｏとでなす角度θは、２０〜８０度の範囲に設定される。
【００２８】
また、円錐面１４ａにおける最小径側のコーナーと最大径側のコーナーは、それぞれ曲面１４ｂ，１４ｃに形成されている。この曲面１４ｂ，１４ｃの曲率半径ｒ１，ｒ２は、内輪２４の内径側角部における円弧状のいわゆるＲ面取り２４ａの曲率半径ｒよりも小さく設定されている。
【００２９】
なお、かしめ部１４の外側面には、径方向外向きに沿う平坦面１４ｄが設けられており、この平坦面１４ｄの径方向長さは、車軸用軸受装置の使用対象となる自動車の種類などによって適宜指定される。
【００３０】
次に、上述したかしめ部１４の形成方法について説明する。まず、ハブホイール１の自由端側外周に対して複列転がり軸受２の内輪２４を外嵌装着してから、ハブホイール１の自由端に対して、従来技術で説明したと同様のローリングかしめを行えばよいのである。
【００３１】
但し、ここでのローリングかしめに用いるかしめ治具４０の先端形状については、図３に示すようなものとする必要がある。
【００３２】
具体的に、図例のかしめ治具４０では、その先端面の中心に凸部４１が、また、この凸部４１の外周に環状陥没部４２が形成されている。この環状陥没部４２の内径側には、径方向に沿う仮想平面Ｌに対して所要角度θ１だけ傾斜する傾斜面４３が設けられていて、環状陥没部４２の外径側には所要角度θ２だけ傾斜する傾斜面４４が設けられた構造になっている。これらの傾斜面４３，４４の傾斜角度θ１，θ２は、θ１＞θ２の関係に設定されている。但し、内径側の傾斜面４３の内周縁は、曲面に形成されており、この曲面は、かしめ部１４における円錐面１４ａの最大径側の曲面１４ｃに対応した曲率半径ｒ２に設定されている。
【００３３】
そして、図４に示すように、上述したようなかしめ治具４０の先端をハブホイール１の自由端にあてがい、かしめ治具４０を一点鎖線Ｐ回りにローリングさせて、最終段階において所要角度αにすると、図２に示すような形状のかしめ部１４を得ることができる。
【００３４】
つまり、かしめ治具４０をローリングさせることにより、かしめ治具４０の環状陥没部４２によりかしめ部１４の全体形状が決定される。詳しくは、ローリングかしめの最終段階において、かしめ治具４０の内径側の傾斜面４３でもってかしめ部１４の内径側角部に円錐面１４ａを形成し、環状陥没部４２の底面でもってかしめ部１４の外端面の径方向途中に平坦部１４ｄを形成し、さらに、外径側の傾斜面４４でもってかしめ部１４の外端面の外径側に傾斜面１４ｅを形成するようになっている。なお、かしめ部１４における最小径側の曲面１４ｂは、かしめの最終段階において、かしめ治具４０の内径側の傾斜面４３および面取り４３ａでもって、だらされることにより、形成される。
【００３５】
つまり、従来例のかしめ形態であれば、ハブホイール１の自由端の肉厚を薄くすればする程、かしめ部１４の内径側角部が外径側に引き延ばされる形態で塑性変形することになって、当該内径側角部の肉厚が薄くなりやすいのであるが、この実施形態でのかしめ治具４０を用いれば、かしめ部１４の内径側角部が引き延ばされる形態に塑性変形しにくくなるので、当該内径側角部の肉厚、つまりかしめ部１４の円錐面１４ａと内輪２４の内径側角部との間の厚みをかしめ前とほぼ同等に維持できるようになる。そのため、かしめ部１４の剛性が十分なものとなり、かしめ後にかしめ部１４が倒れて内輪２４から離れることがなくなる。したがって、複列転がり軸受２の抜け抗力が従来例に比べて増すことになる。
【００３６】
なお、本発明は上記実施形態のみに限定されるものではなく、種々な応用や変形が考えられる。
【００３７】
すなわち、上記実施形態では、車軸用軸受装置として自動車の駆動軸に用いられるものを例に挙げたが、例えば図５に示すような自動車の従動軸に用いられるものにも本発明を適用することができる。この車軸用軸受装置は、ハブホイール１に対して等速ジョイント３を取り付けていない構造であり、そのために、ハブホイール１が中実になっていて、車両インナ側の自由端のみが円筒形状に形成されており、ここが径方向外向きに屈曲されて複列外向きアンギュラ玉軸受２の内輪に対してかしめつけられる。その他、本発明の特徴に係る構成については上記実施形態と同様であるので、その説明を省略する。
【００３８】
【発明の効果】
本発明では、かしめ部の内径側角部の形状を工夫することにより、かしめ部の内径側角部の肉厚をかしめ前とほぼ同等に維持できるようにしているから、内輪の外端面に対してかしめ部を密着もしくは近接させた形態に維持できて、かしめ部による抜け抗力を十分なものにできるようになる。これは、軸体の円筒形自由端の肉厚を薄くする場合において特に有利となる。
【００３９】
特に、請求項４に係る発明のように、かしめ部に設けた円錐面の傾斜角度を所要範囲内に規定すれば、かしめ部の内径側角部の肉厚つまりかしめ部の円錐面と内輪の内径側角部との間の厚みを可及的に大きくするうえで有利となる。
【００４０】
また、請求項５に係る発明のように、かしめ部における円錐面の端部を曲面形状とすれば、かしめ過程においてかしめ部の局部に過大な応力が作用せずに済み、微小亀裂などの発生が回避される。
【図面の簡単な説明】
【図１】本発明の一実施形態に係る車軸用軸受装置を示す縦断面図
【図２】図１のかしめ部の拡大図
【図３】図２のかしめ部を得るためのかしめ治具の縦断面図
【図４】図３のかしめ治具を用いたローリングかしめ形態を示す説明図
【図５】本発明の他の実施形態に係る車軸用軸受装置を示す縦断面図
【図６】従来例の車軸用軸受装置の縦断面図
【図７】図６のかしめ部の拡大図
【図８】従来例での不具合を示す図
【符号の説明】
１ハブホイール
２複列転がり軸受
２４軸受の内輪
１４ハブホイールのかしめ部
１４ａかしめ部の円錐面
１４ｂ円錐面の最小径側の曲面
１４ｃ円錐面の最大径側の曲面
θ 円錐面の傾斜角度[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an axle bearing device and a manufacturing method thereof . Examples of the axle bearing device include an automobile hub unit.
[0002]
[Prior art]
An example of a conventional axle bearing device is US Pat. No. 5,490,732, which is configured as shown in FIGS.
[0003]
In the figure, 80 is a hub wheel, 81 is a double-row rolling bearing such as a double-row outward angular ball bearing, and 82 is a caulking portion.
[0004]
The free end of the hub wheel 80 is bent radially outward by rolling caulking and is caulked against the end surface of the inner ring 83 of the double row rolling bearing 81 to fix the double row rolling bearing 81 to the hub wheel 80 to prevent it from coming off. is doing.
[0005]
Note that the overall shape of the outer end surface of the caulking portion 82 is a rounded curved surface. In addition, the radius of curvature R of the inner diameter side corner of the caulking portion 82 is set to be larger than the radius of curvature r of the arc-shaped so-called R chamfer at the inner peripheral surface corner of the inner ring 83.
[0006]
[Problems to be solved by the invention]
In the above conventional example, when the free end of the hub wheel 80 can be made thicker than the predetermined thickness d1, as shown by the phantom line in FIG. 8, the inner diameter side corner of the caulking portion 82 can be kept thick. Therefore, there is no problem, but when the free end of the hub wheel 80 has to be thinned to a thickness d2 less than a predetermined value, the inner diameter side corner of the caulking portion 82 is stretched as shown by the solid line in FIG. It is plastically deformed in the form and the wall thickness becomes too thin, and the radius of curvature R becomes too large, so that the rigidity of the caulking portion 82 itself tends to be insufficient. Therefore, the reaction force of the axial force applied to the double-row rolling bearing 81 by caulking causes the caulking portion 82 to fall and separate from the end surface of the inner ring 83, and thus the drag force against the unloading load acting on the double-row rolling bearing 81, that is, the pulling-out drag force is increased. Run short.
[0007]
In view of such circumstances, an object of the present invention is to improve a pull-out resistance by a caulking portion in an axle bearing device.
[0008]
[Means for Solving the Problems]
The first axle bearing device according to the present invention is configured such that a free end side cylindrical portion of a shaft body on which a rolling bearing having an R chamfer provided at an inner ring inner diameter corner portion is fitted and fitted is rolled and caulked by a caulking jig. The rolling bearing is secured to the shaft body by being bent in the direction and caulked along the R chamfer of the inner ring of the rolling bearing, and an inner diameter side corner portion of the caulking portion is formed in the caulking jig. It is formed in a conical shape that gradually expands outward in the axial direction by the inclined surface, and the minimum diameter position of this conical surface is arranged on the axially outer side from the inner ring end surface, and the maximum diameter position of this conical surface However, it is characterized by being arranged radially inward from the inner peripheral surface of the inner ring .
In the first configuration, it is preferable that the caulking portion has a flat surface along the radial direction by a flat portion formed on the caulking jig on the outer diameter side of the conical surface. Furthermore, it is desirable that an inclined surface inclined toward the inner ring side is formed on the outer diameter side of the caulking portion by an inclined surface formed on the caulking jig.
[0009]
The second axle bearing device of the present invention is characterized in that, in the first configuration, an angle formed by the conical surface and the shaft body center line is set in a range of 20 to 80 degrees.
[0010]
In the third axle bearing device of the present invention, in the first or second configuration, a corner on the minimum diameter side and a corner on the maximum diameter side of the conical surface are respectively curved surfaces, and the curved surface is a shape of the inner ring. The radius of curvature is set to be smaller than the radius of curvature of the chamfer at the inner diameter side corner.
[0011]
In short, in the present invention, the inner diameter side corner of the caulking portion is not a curved surface but a conical surface. In the case of such a shape, it means that in the caulking process of bending the free end of the shaft body, it is not necessary to be plastically deformed to the form in which the inner diameter side corner portion is extended. The thickness between the conical surface and the inner diameter side corner of the inner ring can be maintained substantially the same as before caulking. For this reason, the rigidity of the caulking portion is improved, and the caulking portion is prevented from falling and being separated from the end surface of the inner ring after caulking.
[0012]
In particular, as in the second configuration, if the inclination angle of the conical surface provided in the caulking portion is defined within a required range, the thickness of the inner diameter side corner portion, that is, the conical surface of the caulking portion and the inner diameter side corner portion of the inner ring This is advantageous in increasing the thickness between the two as much as possible.
[0013]
Further, if the end of the conical surface in the caulking portion is curved as in the third configuration, excessive stress is not applied to the local portion of the caulking portion during the caulking process, and the occurrence of microcracks and the like is avoided. Is done.
In the manufacturing method of the axle bearing device of the present invention, the inner diameter side corner of the caulking portion is formed in a conical shape that gradually expands outward in the axial direction by an inclined surface formed in a caulking jig for rolling caulking. The minimum diameter position of the conical surface is disposed on the axially outer side than the inner ring end surface, and the maximum diameter position of the conical surface is disposed on the radially inner side of the inner ring inner peripheral surface. To do.
As the caulking jig, a convex part is formed at the center of the front end surface, an annular depression is formed on the outer periphery of the convex part, and the inclined surface is formed on the inner diameter side of the annular depression.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
The details of the present invention will be described based on embodiments shown in the drawings. Here, the hub unit of the type used for the drive wheel of a motor vehicle is mentioned as an example as an axle bearing device.
[0015]
1 to 4 show an embodiment of the present invention. 1 is a longitudinal sectional view showing an axle bearing device, FIG. 2 is an enlarged view of a caulking portion, FIG. 3 is a longitudinal sectional view of a caulking jig for obtaining the caulking portion of FIG. 1, and FIG. It is explanatory drawing which shows the rolling caulking form using 3 caulking jigs.
[0016]
The axle bearing device of the illustrated example includes a hub wheel 1, a double row rolling bearing 2, and a constant velocity joint 3.
[0017]
The hub wheel 1 has a hollow structure, and a radially outward flange 11 is formed at an axially intermediate portion of the outer peripheral surface, and a spline (not shown) is formed in a required region of the hollow hole. In the outer peripheral surface, the raceway surface 12 of the balls 22 group on the vehicle outer side in the double row rolling bearing 2 is formed on the vehicle inner side of the flange 11.
[0018]
The double row rolling bearing 2 includes a single outer ring 21 having two rows of raceway grooves, a plurality of balls 22 as rolling elements arranged in two rows, two crown-shaped cages 23, and a vehicle inner side. The inner ring 24 is composed of an inner ring 24 related to the ball 22 group of the balls, and the raceway surface of the hub wheel 1 is used for the inner ring of the ball 22 group on the vehicle outer side as described above. Therefore it does not exist.
[0019]
The constant velocity joint 3 is referred to as a well-known Rzeppa type (Burfield type) constant velocity joint, and includes an outer ring 31, an inner ring 32, a ball 33, a cage 34, and the like. The outer ring 31 includes a bowl-shaped part 35 in which the inner ring 32, the ball 33, the retainer 34, and the like are accommodated and a shaft part 36 that is integrally connected to the small-diameter side of the bowl-shaped part 35. A spline is formed on the outer peripheral surface of the shaft portion 36, and the spline is fitted into the hollow hole of the hub wheel 1.
[0020]
Then, a disc rotor and a wheel of a disc brake device (not shown) are assigned to the flange 11 of the hub wheel 1 and attached by a plurality of bolts 13. A radially outward flange 25 provided on the outer ring 21 of the double-row rolling bearing 2 is bolted to a vehicle body (not shown) or the like. Further, the shaft 5 is spline-fitted to the inner ring 32 of the constant velocity joint 3 and is fixed by a retaining ring (not shown) or the like. The other end of the shaft 5 is attached to a vehicle differential apparatus via another constant velocity joint (not shown).
[0021]
In such an axle bearing device, the rotational power of the shaft 5 is transmitted to a wheel (not shown) attached to the hub wheel 1 via the constant velocity joint 3.
[0022]
A double row rolling bearing 2 is attached to the outer peripheral surface of the hub wheel 1. The end portion on the vehicle inner side of the hub wheel 1 is bent outward in the radial direction, and is caulked from the R chamfer 24 a of the inner peripheral surface corner portion of the inner ring 24 of the double row rolling bearing 2 to the end surface on the vehicle inner side. ing. This caulking portion is denoted by reference numeral 14.
[0023]
A constant velocity joint 3 is coupled to the hub wheel 1 in the form of being adjacent to the vicinity of the double row rolling bearing 2. In other words, in the hollow hole of the hub wheel 1, a spline is formed only in the intermediate region in the axial direction, and the cylinder in which the vehicle inner side region and the vehicle outer side region are larger than the diameter of the groove bottom in the spline in the axial direction intermediate region. Formed on the surface. Reference numeral 15 is assigned to the enlarged diameter area on the vehicle inner side, and reference numeral 16 is assigned to the enlarged diameter area on the vehicle outer side. A circumferential groove 37 is provided on the end edge side of the shaft portion 36 in the outer ring 31 of the constant velocity joint 3. The C-shaped retaining ring 6 is fitted into the circumferential groove 37 so as to partially protrude. Then, the shaft portion 36 of the outer ring 31 of the constant velocity joint 3 is spline-fitted from the vehicle inner side to the hollow hole of the hub wheel 1, but the vehicle inner side end portion of the spline of the shaft portion 36 is the hub wheel 1. The C-shaped retaining ring 6 attached to the shaft portion 36 reaches the vehicle outer side diameter-enlarged region 16 in the hollow hole, so that the C-shaped retaining ring 6 Expands outward in the radial direction and comes into contact with the expanded region. Thus, the spline of the hub wheel 1 is sandwiched between the vehicle inner side edge of the spline of the shaft portion 36 and the C-shaped retaining ring 6 from both sides in the axial direction, and the constant velocity joint 3 is connected to the hub wheel 1. Are in a non-separated state.
[0024]
In this state, it is managed so that a required gap is formed between the caulking portion 14 and the flange portion 35 in the outer ring 31 of the constant velocity joint 3, and is applied to the caulking portion 14 at the time of caulking. A load other than the axial force does not act at all. Note that the gap portion may be eliminated by abutting the hooked portion 35 of the constant velocity joint 3 against the caulking portion 14.
[0025]
This embodiment is characterized by the shape of the caulking portion 14 of the hub wheel 1 and will be described below.
[0026]
That is, as shown in FIG. 2, the inner diameter side corner of the caulking portion 14 is formed on a conical surface 14 a that gradually increases in diameter toward the vehicle inner side. The position of the minimum diameter in the conical surface 14a is disposed on the vehicle inner side with respect to the vertical line g along the end surface of the inner ring 24 of the double row rolling bearing 2.
[0027]
The angle θ formed by the conical surface 14a and the central axis O of the hub wheel 1 is set in the range of 20 to 80 degrees.
[0028]
Further, the corner on the minimum diameter side and the corner on the maximum diameter side of the conical surface 14a are formed on the curved surfaces 14b and 14c, respectively. The curvature radii r1 and r2 of the curved surfaces 14b and 14c are set to be smaller than the curvature radius r of the arc-shaped so-called R chamfer 24a at the inner diameter side corner of the inner ring 24.
[0029]
In addition, the outer surface of the caulking portion 14 is provided with a flat surface 14d extending radially outward, and the radial length of the flat surface 14d is the type of automobile that is a target of use of the axle bearing device. As appropriate.
[0030]
Next, a method for forming the caulking portion 14 described above will be described. First, after the outer ring 24 of the double row rolling bearing 2 is fitted on the outer periphery of the free end side of the hub wheel 1, the same rolling caulking as described in the prior art is applied to the free end of the hub wheel 1. Just do it.
[0031]
However, the tip shape of the caulking jig 40 used for rolling caulking here needs to be as shown in FIG.
[0032]
Specifically, in the caulking jig 40 shown in the figure, a convex portion 41 is formed at the center of the tip surface, and an annular depressed portion 42 is formed on the outer periphery of the convex portion 41. An inclined surface 43 that is inclined by a required angle θ1 with respect to a virtual plane L along the radial direction is provided on the inner diameter side of the annular recessed portion 42, and only the required angle θ2 is provided on the outer diameter side of the annular recessed portion 42. An inclined surface 44 that is inclined is provided. The inclination angles θ1 and θ2 of these inclined surfaces 43 and 44 are set to have a relation of θ1> θ2. However, the inner peripheral edge of the inclined surface 43 on the inner diameter side is formed into a curved surface, and this curved surface is set to a curvature radius r2 corresponding to the curved surface 14c on the maximum diameter side of the conical surface 14a in the caulking portion 14.
[0033]
Then, as shown in FIG. 4, the tip of the caulking jig 40 as described above is applied to the free end of the hub wheel 1, and the caulking jig 40 is rolled around the alternate long and short dash line P to reach the required angle α in the final stage. Then, a caulking portion 14 having a shape as shown in FIG. 2 can be obtained.
[0034]
That is, by rolling the caulking jig 40, the overall shape of the caulking portion 14 is determined by the annular recessed portion 42 of the caulking jig 40. Specifically, in the final stage of rolling caulking, a conical surface 14 a is formed at the inner diameter side corner of the caulking portion 14 by the inclined surface 43 on the inner diameter side of the caulking jig 40, and the caulking portion 14 is formed at the bottom surface of the annular recess 42. A flat portion 14d is formed in the middle of the outer end surface in the radial direction, and an inclined surface 14e is formed on the outer diameter side of the outer end surface of the caulking portion 14 by the inclined surface 44 on the outer diameter side. The curved surface 14b on the minimum diameter side in the caulking portion 14 is formed by being slackened by the inclined surface 43 and the chamfer 43a on the inner diameter side of the caulking jig 40 in the final stage of caulking.
[0035]
That is, in the caulking form of the conventional example, as the thickness of the free end of the hub wheel 1 is reduced, the inner diameter side corner of the caulking part 14 is plastically deformed in a form that is extended to the outer diameter side. Thus, the inner diameter corner portion is likely to be thin, but if the caulking jig 40 in this embodiment is used, the inner diameter corner portion of the caulking portion 14 is not easily deformed plastically. Therefore, the thickness of the inner diameter side corner, that is, the thickness between the conical surface 14a of the caulking portion 14 and the inner diameter side corner of the inner ring 24 can be maintained substantially equal to that before caulking. Therefore, the caulking portion 14 has sufficient rigidity, and the caulking portion 14 does not fall down and leave the inner ring 24 after caulking. Therefore, the slip resistance of the double row rolling bearing 2 is increased as compared with the conventional example.
[0036]
In addition, this invention is not limited only to the said embodiment, Various application and deformation | transformation can be considered.
[0037]
That is, in the above embodiment, the axle bearing device used for the drive shaft of an automobile is taken as an example, but the present invention is also applied to an axle bearing device used for an automobile driven shaft as shown in FIG. Can do. This axle bearing device has a structure in which the constant velocity joint 3 is not attached to the hub wheel 1. For this reason, the hub wheel 1 is solid and only the free end on the vehicle inner side is formed in a cylindrical shape. This is bent outward in the radial direction and caulked against the inner ring of the double row outward angular ball bearing 2. In addition, since the configuration according to the features of the present invention is the same as that of the above embodiment, the description thereof is omitted.
[0038]
【The invention's effect】
In the present invention , by devising the shape of the inner diameter side corner portion of the caulking portion, the thickness of the inner diameter side corner portion of the caulking portion can be maintained substantially equal to that before the caulking portion. The caulking portion can be maintained in a close contact or in a close proximity, and the pulling-out drag force by the caulking portion can be made sufficient. This is particularly advantageous when reducing the thickness of the cylindrical free end of the shaft.
[0039]
In particular, as in the invention according to claim 4 , if the inclination angle of the conical surface provided in the caulking portion is defined within a required range, the thickness of the inner diameter side corner portion of the caulking portion, that is, the conical surface of the caulking portion and the inner ring This is advantageous in increasing the thickness between the inner diameter side corners as much as possible.
[0040]
Further, as in the invention according to claim 5 , if the end portion of the conical surface in the caulking portion is formed into a curved shape, excessive stress is not applied to the local portion of the caulking portion in the caulking process, and microcracks are generated. Is avoided.
[Brief description of the drawings]
1 is a longitudinal sectional view showing an axle bearing device according to an embodiment of the present invention. FIG. 2 is an enlarged view of a caulking portion of FIG. 1. FIG. 3 is a caulking jig for obtaining the caulking portion of FIG. FIG. 4 is an explanatory view showing a rolling caulking form using the caulking jig of FIG. 3. FIG. 5 is a longitudinal sectional view showing an axle bearing device according to another embodiment of the present invention. Fig. 7 is a longitudinal sectional view of an example axle bearing device. Fig. 7 is an enlarged view of a caulking portion in Fig. 6. Fig. 8 is a diagram showing defects in a conventional example.
DESCRIPTION OF SYMBOLS 1 Hub wheel 2 Double row rolling bearing 24 Inner ring 14 of a bearing Caulking part 14a of a hub wheel Conical surface 14b of a caulking part The curved surface 14c of the conical surface on the smallest diameter side The curved surface θ of the conical surface on the maximum diameter side The inclination angle of the conical surface

Claims

An inner ring of the rolling bearing is bent by radially caulking the free end side cylindrical portion of the shaft body on which the rolling bearing having an R chamfer provided at the inner ring inner diameter corner portion is fitted and fitted by a caulking jig. An axle bearing device in which a rolling bearing is secured to a shaft body by caulking along the R chamfer,
The inner diameter side corner of the caulking portion is formed in a conical shape that gradually expands outward in the axial direction by an inclined surface formed in the caulking jig, and the minimum diameter position of the conical surface is smaller than the inner ring end surface. Is also arranged on the outer side in the axial direction, and the maximum diameter position of the conical surface is arranged on the inner side in the radial direction with respect to the inner peripheral surface of the inner ring .

2. The axle part according to claim 1, wherein the caulking part is formed with a flat surface along a radial direction on the outer diameter side of the conical surface by a flat part formed on the caulking jig. Bearing device.

3. The axle according to claim 1, wherein the caulking portion has an inclined surface that is inclined toward the inner ring side by an inclined surface formed on the caulking jig on the outer diameter side thereof. Bearing device.

The axle bearing device according to any one of claims 1 to 3,
An axle bearing device, wherein an angle formed by the conical surface and the central axis of the shaft body is set in a range of 20 to 80 degrees.

The axle bearing device according to any one of claims 1 to 4,
The corner on the minimum diameter side and the corner on the maximum diameter side of the conical surface are respectively curved surfaces, and the curved surface is set to have a curvature radius smaller than the curvature radius of the chamfer at the inner diameter side corner of the inner ring. Axle bearing device characterized by the above.

The free end side cylindrical portion of the shaft body on which the rolling bearing having the R chamfer provided on the inner ring inner diameter corner portion is externally fitted is rolled by caulking jig to bend outward in the radial direction so that the inner ring of the rolling bearing is A method of manufacturing an axle bearing device in which a rolling bearing is secured to a shaft body by caulking along the R chamfer,
The inner diameter side corner of the caulking portion is formed in a conical shape that gradually expands outward in the axial direction by an inclined surface formed in the caulking jig ,
An axle characterized in that the minimum diameter position of the conical surface is disposed on the axially outer side from the end surface of the inner ring, and the maximum diameter position of the conical surface is disposed on the radially inner side of the inner peripheral surface of the inner ring. Of manufacturing a bearing device for a vehicle.

The caulking jig is characterized in that a convex portion is formed at the center of the front end surface, an annular recess is formed on the outer periphery of the convex portion, and the inclined surface is formed on the inner diameter side of the annular recess. A method for manufacturing an axle bearing device according to claim 6.

The free end side cylindrical portion of the shaft body on which the rolling bearing having the R chamfer provided on the inner ring inner diameter corner portion is externally fitted is rolled by caulking jig to bend outward in the radial direction so that the inner ring of the rolling bearing is A method of manufacturing an axle bearing device in which a rolling bearing is secured to a shaft body by caulking along the R chamfer,
In the caulking jig, a convex portion is formed at the center of the tip surface, an annular depression is formed on the outer periphery of the convex portion, a first inclined surface is formed on the inner diameter side of the annular depression, and the annular depression is A flat portion is formed on the bottom surface in the middle of the radial direction, and a second inclined surface is formed on the outer diameter side of the annular depression,
An inner diameter side corner of the caulking portion is formed in a conical shape that gradually expands outward in the axial direction by a first inclined surface formed in the caulking jig, and the minimum diameter position of the conical surface is an inner ring end surface It is arranged on the outside in the axial direction, the maximum diameter position of this conical surface is arranged on the inside in the radial direction with respect to the inner peripheral surface of the inner ring ,
The outer surface of the caulking portion is formed with a flat surface along the radial direction by the flat portion formed on the caulking jig, and the outer diameter side of the caulking portion is a second slope formed on the caulking jig. A method of manufacturing an axle bearing device, wherein an inclined surface inclined toward the inner ring is formed by the surface.