JP7306287B2

JP7306287B2 - hub unit bearing

Info

Publication number: JP7306287B2
Application number: JP2020017641A
Authority: JP
Inventors: 俊太朗松岸; 達男若林
Original assignee: NSK Ltd
Current assignee: NSK Ltd
Priority date: 2020-02-05
Filing date: 2020-02-05
Publication date: 2023-07-11
Anticipated expiration: 2040-02-05
Also published as: JP2021124163A

Description

本発明は、ハブユニット軸受に関する。 The present invention relates to hub unit bearings.

ハブユニット軸受は、車輪を回転自在に支持する装置である。下記特許文献に示すように、ハブユニット軸受は、フランジが設けられた外輪と、車輪が取り付けられるハブと、外輪とハブとの間に配置される複数の転動体と、を備える。外輪のフランジは、複数の締結部と、各締結部の間で周方向に延在する複数の補強部と、を備える。そして、フランジの締結部は、懸架装置のナックルと締結されて、ハブユニット軸受が車両に組み付けられる。通常、ハブの回転軸に沿って切ったフランジの断面形状は、ナックルとの対向面がハブの回転軸と直交する方向に延在しているか、又は、径方向外側に向かうにつれてナックル側に若干倒れるようなテーパ状をしている。 A hub unit bearing is a device that rotatably supports a wheel. As shown in the following patent document, a hub unit bearing includes an outer ring provided with a flange, a hub to which a wheel is attached, and a plurality of rolling elements arranged between the outer ring and the hub. The outer ring flange includes a plurality of fastening portions and a plurality of reinforcing portions extending circumferentially between the fastening portions. The fastening portion of the flange is then fastened to the knuckle of the suspension system, and the hub unit bearing is assembled to the vehicle. Normally, the cross-sectional shape of the flange cut along the axis of rotation of the hub is such that the surface facing the knuckle extends in a direction orthogonal to the axis of rotation of the hub, or slightly toward the knuckle as it goes radially outward. It has a tapered shape that makes it fall down.

特開２００９－１２８３３５号公報JP 2009-128335 A

ところで、フランジとナックルを締結すると、フランジの締結部とナックルの締結部とに、ボルトの軸力が作用する。このため、フランジの締結部とナックルの締結部とのうち一方又は両方は、互いに近づくように変形することがある。そして、このような変形が生じると、フランジの補強部は、ナックルに対して離間し、ナックルに当接しなくなる。つまり、フランジの補強部とナックルとの間には微小な隙間が発生してしまい、外輪とナックルとの結合剛性は低下する。 By the way, when the flange and the knuckle are fastened together, the axial force of the bolt acts on the fastening portion of the flange and the fastening portion of the knuckle. Therefore, one or both of the flange fastening portion and the knuckle fastening portion may be deformed so as to move closer to each other. Then, when such deformation occurs, the reinforcing portion of the flange is separated from the knuckle and is no longer in contact with the knuckle. In other words, a minute gap is generated between the reinforcing portion of the flange and the knuckle, and the coupling rigidity between the outer ring and the knuckle is reduced.

本開示は、上記の課題に鑑みてなされたものであって、フランジとナックルとの締結時、フランジの補強部がナックルに確実に当接するハブユニット軸受を提供することを目的とする。 The present disclosure has been made in view of the above problems, and an object thereof is to provide a hub unit bearing in which the reinforcing portion of the flange reliably contacts the knuckle when the flange and the knuckle are fastened together.

上記の目的を達成するため、本開示の一態様に係るハブユニット軸受は、外輪と、前記外輪に回転自在なハブと、前記外輪と前記ハブとの間に配置された複数の転動体と、を備え、前記外輪は、筒状の外輪本体と、前記外輪本体の外周面から突出し、かつナックルとの締結後に前記ナックルと対向する対向面、及び前記対向面と反対側の反対面を有するフランジと、前記外輪本体の外周面と、前記フランジの反対面と、が交わる隅部と、を有し、前記フランジは、前記ナックルと締結される複数の締結部と、複数の前記締結部の間で周方向に延在する複数の補強部と、を有し、前記隅部は、周方向の一部を熱処理して成る第１隅部と、周方向の残部であり、熱処理が回避された第２隅部と、を有し、前記締結部は、前記ハブの回転軸から視て前記第２隅部と重なり、前記回転軸と直交する方向に延在し、少なくとも１つ以上の前記補強部は、前記回転軸から視て周方向の一部が前記第１隅部と重なり、径方向外側に離隔するにつれて前記反対面から前記対向面の方に傾斜している。 To achieve the above object, a hub unit bearing according to one aspect of the present disclosure includes an outer ring, a hub rotatable on the outer ring, a plurality of rolling elements arranged between the outer ring and the hub, The outer ring comprises a cylindrical outer ring body, a flange having a facing surface that protrudes from the outer peripheral surface of the outer ring body and faces the knuckle after fastening with the knuckle, and an opposite surface that is opposite to the facing surface and a corner where the outer peripheral surface of the outer ring main body and the opposite surface of the flange intersect, and the flange includes a plurality of fastening portions that are fastened to the knuckle and between the plurality of fastening portions. and a plurality of reinforcing portions extending in the circumferential direction, and the corners are a first corner formed by heat-treating a part of the circumferential direction and the remaining portion in the circumferential direction, and heat treatment is avoided. a second corner, wherein the fastening portion overlaps with the second corner when viewed from the axis of rotation of the hub, extends in a direction orthogonal to the axis of rotation, and includes at least one or more of the reinforcements. The portion overlaps the first corner portion in a circumferential direction when viewed from the rotation shaft, and is inclined from the opposite surface toward the opposite surface as it is separated radially outward.

補強部は、対向面の方に傾斜しているため、締結部よりもナックル側に突出している。よって、ボルトの軸力により、フランジの締結部がナックルの締結部寄りに変形したとしても、補強部は、ナックルに確実に当接する。以上から、フランジの補強部とナックルとの間に微小な隙間が発生せず、外輪とナックルとの結合剛性が高い。また、機械加工で、補強部を締結部よりもナックル側に突出させると高コストとなる。一方で、本開示によれば、熱処理により行っており、低コストで製造できる。 Since the reinforcing portion is inclined toward the facing surface, it protrudes further toward the knuckle than the fastening portion. Therefore, even if the fastening portion of the flange is deformed toward the fastening portion of the knuckle due to the axial force of the bolt, the reinforcing portion reliably contacts the knuckle. As described above, a minute gap is not generated between the reinforcing portion of the flange and the knuckle, and the coupling rigidity between the outer ring and the knuckle is high. Further, if the reinforcing portion is made to protrude toward the knuckle side from the fastening portion by machining, the cost becomes high. On the other hand, according to the present disclosure, the heat treatment is performed and can be manufactured at low cost.

上記のハブユニット軸受の一態様として、複数の前記締結部は、前記ナックルの上部と締結される一対の第１締結部と、前記ナックルの下部と締結される一対の第２締結部と、を備え、複数の前記補強部は、前記第１締結部と前記第２締結部との間で延在する一対の第１補強部と、一対の前記第１締結部の間と、一対の前記第２締結部の間と、で延在する一対の第２補強部と、を有し、一対の前記第１補強部は、前記回転軸から視て周方向の一部が前記第１隅部と重なっている。 As one aspect of the above hub unit bearing, the plurality of fastening portions includes a pair of first fastening portions fastened to the upper portion of the knuckle and a pair of second fastening portions fastened to the lower portion of the knuckle. a pair of first reinforcing portions extending between the first fastening portion and the second fastening portion; between the pair of first fastening portions; and a pair of second reinforcing portions extending between and between the two fastening portions, and a part of the pair of first reinforcing portions in the circumferential direction when viewed from the rotation shaft is the first corner portion. overlapping.

フランジとナックルとを締結した後、一対の第１補強部は、回転軸を挟んで車両の前後方向に並ぶ。よって、外輪とナックルとにおけるトー角方向の結合剛性が高くなる。 After fastening the flange and the knuckle, the pair of first reinforcing portions are arranged in the front-rear direction of the vehicle across the rotation shaft. Therefore, the coupling rigidity in the toe angle direction between the outer ring and the knuckle is increased.

上記のハブユニット軸受の一態様として、複数の前記締結部は、前記ナックルの上部と締結される一対の第１締結部と、前記ナックルの下部と締結される一対の第２締結部と、を備え、複数の前記補強部は、前記第１締結部と前記第２締結部との間で延在する一対の第１補強部と、一対の前記第１締結部の間と、一対の前記第２締結部の間と、で延在する一対の第２補強部と、を有し、一対の前記第２補強部は、前記回転軸から視て周方向の一部が前記第１隅部と重なっている。 As one aspect of the above hub unit bearing, the plurality of fastening portions includes a pair of first fastening portions fastened to the upper portion of the knuckle and a pair of second fastening portions fastened to the lower portion of the knuckle. a pair of first reinforcing portions extending between the first fastening portion and the second fastening portion; between the pair of first fastening portions; and a pair of second reinforcing portions extending between and between the two fastening portions, and a part of the pair of second reinforcing portions in the circumferential direction when viewed from the rotation shaft is the first corner portion. overlapping.

フランジとナックルとを締結した後、一対の第２補強部は、回転軸を挟んで車両の上下方向に並ぶ。よって、外輪とナックルとにおけるキャンバー角方向の結合剛性が高くなる。 After fastening the flange and the knuckle, the pair of second reinforcing portions are arranged in the vertical direction of the vehicle with the rotation shaft interposed therebetween. Therefore, the coupling rigidity in the camber angle direction between the outer ring and the knuckle is increased.

上記のハブユニット軸受の一態様として、複数の前記締結部は、前記ナックルの上部と締結される１つの第１締結部と、前記ナックルの下部と締結される一対の第２締結部と、を備え、複数の前記補強部は、前記第１締結部と前記第２締結部との間で延在する一対の第１補強部と、一対の第２締結部の間で延在する１つの第２補強部と、を有し、一対の前記第１補強部は、前記回転軸から視て周方向の一部が前記第１隅部と重なっている。 As one aspect of the above hub unit bearing, the plurality of fastening portions includes one first fastening portion fastened to the upper portion of the knuckle and a pair of second fastening portions fastened to the lower portion of the knuckle. wherein the plurality of reinforcing portions includes a pair of first reinforcing portions extending between the first fastening portion and the second fastening portion, and one second fastening portion extending between the pair of second fastening portions. 2 reinforcing portions, and a part of the pair of first reinforcing portions in the circumferential direction overlaps the first corner portion when viewed from the rotating shaft.

本開示のハブユニット軸受によれば、締結時にフランジの補強部がナックルに確実に当接し、外輪とナックルとの結合剛性が高い。 According to the hub unit bearing of the present disclosure, the reinforcing portion of the flange reliably contacts the knuckle when tightened, and the rigidity of the connection between the outer ring and the knuckle is high.

図１は、実施形態１に係るハブユニット軸受を回転軸に沿って切った断面図であり、詳細には図２のＩ－Ｉ線矢視断面図である。FIG. 1 is a cross-sectional view of the hub unit bearing according to Embodiment 1 taken along the rotation axis, and more specifically, a cross-sectional view taken along line II in FIG. 図２は、実施形態１に係る外輪のみを抽出して軸方向外側から視た図である。FIG. 2 is a view of only the outer ring according to Embodiment 1, which is extracted and viewed from the outside in the axial direction. 図３は、図２のＩＩＩ－ＩＩＩ線矢視断面図である。3 is a cross-sectional view taken along line III-III in FIG. 2. FIG. 図４は、図２のＩＶ－ＩＶ線矢視断面図である。4 is a sectional view taken along line IV-IV in FIG. 2. FIG. 図５は、実施形態２に係る外輪のみを抽出して軸方向外側から視た図である。FIG. 5 is a view of only the outer ring according to Embodiment 2, which is extracted and viewed from the outside in the axial direction. 図６は、実施形態３に係る外輪のみを抽出して軸方向外側から視た図である。FIG. 6 is a view of only the outer ring according to Embodiment 3, which is extracted and viewed from the outside in the axial direction. 図７は、実施形態４に係る外輪のみを抽出して軸方向外側から視た図である。FIG. 7 is a view of only the outer ring according to Embodiment 4, which is extracted and viewed from the outside in the axial direction.

以下、本発明につき図面を参照しつつ詳細に説明する。なお、下記の発明を実施するための形態（以下、実施形態という）により本発明が限定されるものではない。また、下記実施形態における構成要素には、当業者が容易に想定できるもの、実質的に同一のもの、いわゆる均等の範囲のものが含まれる。さらに、下記実施形態で開示した構成要素は適宜組み合わせることが可能である。 Hereinafter, the present invention will be described in detail with reference to the drawings. It should be noted that the present invention is not limited by the following modes for carrying out the invention (hereinafter referred to as embodiments). In addition, components in the following embodiments include those that can be easily assumed by those skilled in the art, those that are substantially the same, and those that fall within a so-called equivalent range. Furthermore, the constituent elements disclosed in the following embodiments can be combined as appropriate.

図１は、実施形態１に係るハブユニット軸受を回転軸に沿って切った断面図であり、詳細には図２のＩ－Ｉ線矢視断面図である。図２は、実施形態１に係る外輪のみを抽出して軸方向外側から視た図である。図３は、図２のＩＩＩ－ＩＩＩ線矢視断面図である。図４は、図２のＩＶ－ＩＶ線矢視断面図である。 FIG. 1 is a cross-sectional view of the hub unit bearing according to Embodiment 1 taken along the rotation axis, and more specifically, a cross-sectional view taken along line II in FIG. FIG. 2 is a view of only the outer ring according to Embodiment 1, which is extracted and viewed from the outside in the axial direction. 3 is a cross-sectional view taken along line III-III in FIG. 2. FIG. 4 is a sectional view taken along line IV-IV in FIG. 2. FIG.

（実施形態１）
実施形態１に係るハブユニット軸受１は、自動車の車体の一部である懸架装置に装着されて車輪を回転自在に支持するための装置である。また、本実施形態のハブユニット軸受１は、駆動輪を支持するための駆動輪用ハブユニット軸受であり、ハブ３の中心部には駆動軸を通す為のスプライン孔６ａが設けられている。なお、本開示のハブユニット軸受１は、従動輪を支持する従動輪用ハブユニット軸受に適用してもよい。図１に示すように、ハブユニット軸受１は、筒状の外輪２と、一部が外輪２の内周側に配置されたハブ３と、外輪２とハブ３との間に配置された複数の転動体４と、を備える。以下の説明において、ハブ３の回転軸Ｏと平行な方向を単に軸方向という。 (Embodiment 1)
A hub unit bearing 1 according to Embodiment 1 is a device that is mounted on a suspension system that is a part of the vehicle body of an automobile to rotatably support a wheel. Further, the hub unit bearing 1 of the present embodiment is a driving wheel hub unit bearing for supporting a driving wheel, and the hub 3 has a spline hole 6a through which a driving shaft passes through at the center thereof. Note that the hub unit bearing 1 of the present disclosure may be applied to a driven wheel hub unit bearing that supports a driven wheel. As shown in FIG. 1, the hub unit bearing 1 includes a tubular outer ring 2, a hub 3 partially arranged on the inner peripheral side of the outer ring 2, and a plurality of bearings arranged between the outer ring 2 and the hub 3. and a rolling element 4 of In the following description, the direction parallel to the rotation axis O of the hub 3 is simply called the axial direction.

外輪２は、中炭素鋼を熱間鍛造した後、旋削加工することにより中間製造物を製造する。次に、その中間製造物の複列の外輪軌道２ａ、２ｂとなる位置に高周波焼き入れを行い、硬化層９ａ、９ｂを形成する。その後、複列の外輪軌道２ａ、２ｂとなる位置及びシール８ａ、８ｂの圧入面となる位置に研削加工を行うことで外輪２が製造される。外輪２は、ハブ３の回転軸Ｏを中心に円筒状を成す外輪本体５と、外輪本体５の外周面から径方向外側に突出するフランジ１０と、外輪本体５の外周面５ａとフランジ１０の反対面１０ｂとが交わる隅部３０と、を備える。 The outer ring 2 is produced as an intermediate product by hot forging medium carbon steel and then turning the hot forged medium carbon steel. Next, induction hardening is performed on the position of the intermediate product to be the double-row outer ring raceways 2a, 2b to form hardened layers 9a, 9b. After that, the outer ring 2 is manufactured by performing a grinding process on the double-row outer ring raceways 2a and 2b and the press-fitting surfaces of the seals 8a and 8b. The outer ring 2 includes an outer ring main body 5 having a cylindrical shape around the rotation axis O of the hub 3, a flange 10 projecting radially outward from the outer peripheral surface of the outer ring main body 5, and an outer peripheral surface 5a of the outer ring main body 5 and the flange 10. and a corner 30 where the opposite surface 10b intersects.

外輪本体５の内周面には、複列の外輪軌道２ａ、２ｂが設けられている。外輪本体５の端部５ｂは、ナックル５０との締結時、ナックル５０の孔部５１に挿入される。フランジ１０は、懸架装置のナックル５０とボルト６０で締結される。また、フランジ１０がナックル５０と締結された場合、外輪２は、車両の車幅方向に開口する。よって、ハブ３の回転軸Ｏは、ナックル５０との締結後、車幅方向に延在する。 Double-row outer ring raceways 2 a and 2 b are provided on the inner peripheral surface of the outer ring main body 5 . The end portion 5b of the outer ring main body 5 is inserted into the hole portion 51 of the knuckle 50 when the knuckle 50 is fastened. Flange 10 is fastened with suspension knuckles 50 and bolts 60 . Further, when the flange 10 is fastened to the knuckle 50, the outer ring 2 opens in the width direction of the vehicle. Therefore, the rotation axis O of the hub 3 extends in the vehicle width direction after fastening with the knuckle 50 .

フランジ１０は、軸方向の一方を向く対向面１０ａと、軸方向の他方を向く反対面１０ｂと、を備える。対向面１０ａは、ナックル５０との締結後、ナックル５０の取り付け面５２と対向して当接すべき面で、熱間鍛造後であって外輪軌道２ａ、２ｂの熱処理前（高周波焼き入れ前）に旋削により仕上げられている。対向面１０ａは、ナックル５０への取り付け後、車幅方向内側を向く。以下、軸方向において、対向面１０ａが向く方向を軸方向内側と称し、反対面１０ｂが向く方向を軸方向外側と称する。フランジ１０と隅部３０との詳細については後述する。 The flange 10 has a facing surface 10a facing one axial direction and an opposite surface 10b facing the other axial direction. The facing surface 10a is a surface to face and abut against the mounting surface 52 of the knuckle 50 after fastening with the knuckle 50, after hot forging and before heat treatment of the outer ring raceways 2a and 2b (before induction hardening). It is finished by lathe turning. After being attached to the knuckle 50, the facing surface 10a faces inward in the vehicle width direction. Hereinafter, in the axial direction, the direction in which the facing surface 10a faces is referred to as the axially inner side, and the direction in which the opposite surface 10b faces is referred to as the axially outer side. Details of the flange 10 and the corner 30 will be described later.

ハブ３は、外周面に複列の内輪軌道３ａ、３ｂを有している。ハブ３は、ハブ輪６と、内輪７と、を備える。ハブ輪６は、回転軸Ｏを中心に円筒状を成している。ハブ輪６の内周面には、スプライン孔６ａが設けられている。ハブユニット軸受１が車体に組み付けられた後、ハブ輪６の内部には、図示しない駆動軸が挿入される。また、スプライン孔６ａには、駆動軸がスプライン嵌合される。これにより、駆動軸が回転すると、ハブ３が回転軸Ｏを中心に回転する。 The hub 3 has double-row inner ring raceways 3a and 3b on its outer peripheral surface. The hub 3 includes a hub ring 6 and an inner ring 7. The hub wheel 6 has a cylindrical shape with the rotation axis O as the center. The inner peripheral surface of the hub wheel 6 is provided with a spline hole 6a. After the hub unit bearing 1 is assembled to the vehicle body, a drive shaft (not shown) is inserted into the hub wheel 6 . A drive shaft is spline-fitted into the spline hole 6a. Accordingly, when the drive shaft rotates, the hub 3 rotates around the rotation axis O. As shown in FIG.

ハブ輪６における軸方向の中間部の外周面には、内輪軌道３ａが設けられている。ハブ輪６の軸方向外側の端部には、径方向外側に突出するフランジ６ｂが設けられている。このフランジ６ｂは、図示しない車輪のホイールと、図示しない制動装置のディスクと、が取り付けられる。また、ハブ輪６の軸方向内側の端寄りには、外径が小径に形成された小径部６ｃが設けられている。ハブ輪６の軸方向内側の端部には、一部を径方向の外側に塑性変形させて成るかしめ部６ｄが設けられている。 An inner ring raceway 3a is provided on the outer peripheral surface of the hub wheel 6 at an intermediate portion in the axial direction. A flange 6b protruding radially outward is provided at the axially outer end of the hub wheel 6 . To this flange 6b are attached a wheel of a wheel (not shown) and a disc of a braking device (not shown). A small-diameter portion 6c having a small outer diameter is provided near the axially inner end of the hub wheel 6. As shown in FIG. An axially inner end portion of the hub wheel 6 is provided with a crimped portion 6d formed by plastically deforming a portion of the hub wheel 6 radially outwardly.

内輪７は、外周面に内輪軌道３ｂが設けられた部品である。内輪７は、小径部６ｃの外周側に嵌合されている。そして、内輪７は、かしめ部６ｄにより、軸方向外側に押圧されている。このため、内輪７は、ハブ輪６から分離しないようになっている。さらに、外輪軌道２ｂと内輪軌道３ｂとの間に配置される転動体４には、予圧が付与されている。 The inner ring 7 is a component having an inner ring raceway 3b on its outer peripheral surface. The inner ring 7 is fitted on the outer peripheral side of the small diameter portion 6c. The inner ring 7 is pressed outward in the axial direction by the crimped portion 6d. Therefore, the inner ring 7 is not separated from the hub ring 6. - 特許庁Further, a preload is applied to the rolling elements 4 arranged between the outer ring raceway 2b and the inner ring raceway 3b.

転動体４は、複列の外輪軌道２ａ、２ｂと複列の内輪軌道３ａ、３ｂとの間のそれぞれに、複数個ずつ転動自在に設けられている。本実施形態の転動体４は、球体である。なお、本開示のハブユニット軸受は、球体の転動体に限らず、円すいころを使用してもよい。また、外輪２とハブ３との間には、転動体４、４に向かって異物が侵入することを防止し、かつグリースが外部に漏出することを防止するためのシール８ａ、８ｂが設けられている。 A plurality of rolling elements 4 are rotatably provided between the double-row outer ring raceways 2a, 2b and the double-row inner ring raceways 3a, 3b, respectively. The rolling element 4 of this embodiment is a sphere. Note that the hub unit bearing of the present disclosure is not limited to spherical rolling elements, and tapered rollers may be used. Seals 8a and 8b are provided between the outer ring 2 and the hub 3 to prevent foreign matter from entering toward the rolling elements 4 and 4 and to prevent grease from leaking to the outside. ing.

図２に示すように、フランジ１０は、複数の締結部１１と、複数の締結部１１の間で周方向に延在する複数の補強部２０と、を備える。締結部１１は、ナックル５０と締結される部位である。実施形態１の締結部１１は、一対の第１締結部１２、１２と、一対の第２締結部１３、１３と、を備える。補強部２０は、締結部１１と外輪本体５との剛性を高めるため部位である。実施形態１の補強部２０は、一対の第１補強部２１と、一対の第２補強部２２と、を備える。 As shown in FIG. 2 , the flange 10 includes a plurality of fastening portions 11 and a plurality of reinforcing portions 20 circumferentially extending between the fastening portions 11 . The fastening portion 11 is a portion to be fastened with the knuckle 50 . The fastening portion 11 of Embodiment 1 includes a pair of first fastening portions 12 and 12 and a pair of second fastening portions 13 and 13 . The reinforcement portion 20 is a portion for increasing the rigidity between the fastening portion 11 and the outer ring main body 5 . The reinforcing portion 20 of Embodiment 1 includes a pair of first reinforcing portions 21 and a pair of second reinforcing portions 22 .

締結部１１と補強部２０とは、周方向に連続している。フランジ１０における締結部１１と補強部２０との境界線は、仮想接線Ｌ１と重なっている。仮想接線Ｌ１は、回転軸Ｏから径方向外側に延出し、かつ締結部１１の外周面と重なる仮想円Ｃに接している（図２の右下の方を参照）。また、仮想接線Ｌ１は、一つの仮想円Ｃに対して２つ発生するが、この２つの仮想接線Ｌ１に挟まれている範囲が締結部１１である。なお、図２において、仮想接線Ｌ１を引いていない他の締結部１１には、その締結部１１の範囲を明確にするため、一点鎖線を引いている。 The fastening portion 11 and the reinforcing portion 20 are continuous in the circumferential direction. A boundary line between the fastening portion 11 and the reinforcement portion 20 in the flange 10 overlaps the imaginary tangent line L1. The imaginary tangent line L1 is in contact with an imaginary circle C that extends radially outward from the rotation axis O and overlaps the outer peripheral surface of the fastening portion 11 (see the lower right of FIG. 2). Two imaginary tangent lines L1 are generated with respect to one imaginary circle C, and the fastening portion 11 is a range sandwiched between the two imaginary tangent lines L1. In addition, in FIG. 2, other fastening portions 11 for which the imaginary tangent line L1 is not drawn are drawn with dashed lines in order to clarify the range of the fastening portions 11. As shown in FIG.

第１締結部１２は、軸方向に貫通し、内周面にねじ穴が形成された雌ねじ部１２ａを有している。同様に、第２締結部１３は、軸方向に貫通し、内周面にねじ穴が形成された雌ねじ部１３ａを有している。図１に示すように、雌ねじ部１２ａ、１３ａ（図１において雌ねじ部１２ａは不図示）は、ナックル５０との締結の際、ナックル５０を貫通するボルト６０が螺合するようになっている。 The first fastening portion 12 has a female screw portion 12a that penetrates in the axial direction and has a screw hole formed on the inner peripheral surface thereof. Similarly, the second fastening portion 13 has a female threaded portion 13a that penetrates in the axial direction and has a threaded hole formed in the inner peripheral surface thereof. As shown in FIG. 1, the female threaded portions 12a and 13a (the female threaded portion 12a is not shown in FIG. 1) are adapted to be screwed together with a bolt 60 passing through the knuckle 50 when the knuckle 50 is fastened.

図２に示すように、第１締結部１２は、ナックル５０の上部と締結される。第２締結部１３は、ナックル５０の下部と締結される。よって、第１締結部１２と第２締結部１３とが配置される配置方向は、ナックル５０との締結後、車両の上下方向となる。以下の説明において、配置方向と軸方向とのそれぞれに直交する方向を交差方向と称する。 As shown in FIG. 2 , the first fastening portion 12 is fastened to the upper portion of the knuckle 50 . The second fastening portion 13 is fastened to the lower portion of the knuckle 50 . Therefore, the arrangement direction in which the first fastening portion 12 and the second fastening portion 13 are arranged is the vertical direction of the vehicle after fastening with the knuckle 50 . In the following description, a direction orthogonal to the arrangement direction and the axial direction is called a cross direction.

第１補強部２１は、第１締結部１２と第２締結部１３との間に配置されている。一対の第１補強部２１、２１は、回転軸Ｏを挟んで交差方向に互いに離隔している。なお、交差方向は、ナックル５０との締結後、車両の前後方向となる。また、第２補強部２２は、一対の第１締結部１２、１２の間と、一対の第２締結部１３、１３の間に配置されている。そして、一対の第２補強部２２、２２は、回転軸Ｏを挟んで配置方向に互いに離隔している。 The first reinforcing portion 21 is arranged between the first fastening portion 12 and the second fastening portion 13 . The pair of first reinforcing portions 21, 21 are separated from each other in the crossing direction with the rotation axis O interposed therebetween. Note that the crossing direction is the longitudinal direction of the vehicle after the knuckle 50 is engaged. Also, the second reinforcing portion 22 is arranged between the pair of first fastening portions 12 and 12 and between the pair of second fastening portions 13 and 13 . The pair of second reinforcing portions 22 and 22 are separated from each other in the arrangement direction with the rotation axis O interposed therebetween.

隅部３０は、回転軸Ｏを中心に周方向に延在し、環状を成している。隅部３０は、外輪２の製造の際、周方向の一部に高周波焼き入れにより硬化層が設けられている。よって、隅部３０は、熱処理が回避された非硬化処理領域４１と、熱処理されて硬化している硬化処理領域４２と、を有している。なお、硬化処理領域４２を第１隅部と称する場合がある。非硬化処理領域４１を第２隅部と称する場合がある。 The corner portion 30 extends in the circumferential direction around the rotation axis O and has an annular shape. When the outer ring 2 is manufactured, the corner portion 30 is partially provided with a hardened layer by induction hardening in the circumferential direction. Therefore, the corner 30 has a non-hardened region 41 where heat treatment is avoided and a hardened region 42 which is hardened by heat treatment. In addition, the hardening process area|region 42 may be called a 1st corner. The non-cured region 41 may be referred to as a second corner.

以下において、隅部３０を締結部用隅部３１と補強部用隅部３２とに分けて、非硬化処理領域４１と硬化処理領域４２との関係を説明する。締結部用隅部３１は、隅部３０のうち、回転軸Ｏから視て締結部１１と重なる部分である。補強部用隅部３２は、隅部３０のうち、回転軸Ｏから視て補強部２０と重なる部分である。 In the following, the corner 30 is divided into a fastening portion corner 31 and a reinforcing portion corner 32, and the relationship between the non-hardened region 41 and the hardened region 42 will be described. The fastening portion corner portion 31 is a portion of the corner portion 30 that overlaps the fastening portion 11 when viewed from the rotation axis O. As shown in FIG. The reinforcing portion corner portion 32 is a portion of the corner portion 30 that overlaps with the reinforcing portion 20 when viewed from the rotation axis O. As shown in FIG.

締結部用隅部３１は、周方向の全てが非硬化処理領域４１となっている。非硬化処理領域４１は、外輪本体５やフランジ１０と同じと同じ結晶構造となっている。これにより、図３に示すように、第１締結部１２は、回転軸Ｏと直交する方向に直線状に延在している（なお、図３において回転軸Ｏは不図示）。言い換えると、第１締結部１２の形状は、旋削時から変形していない。そして、第１締結部１２の対向面１０ａは、回転軸Ｏを垂線とする仮想平面Ｈに沿って平行に延在している。なお、特に図示しないが、第２締結部１３においても回転軸Ｏと直交する方向に直線状に延在している。 The corner portion 31 for fastening portion has a non-hardening treatment region 41 in the entire circumferential direction. The non-hardened region 41 has the same crystal structure as the outer ring main body 5 and the flange 10 . Thereby, as shown in FIG. 3, the first fastening portion 12 extends linearly in a direction orthogonal to the rotation axis O (the rotation axis O is not shown in FIG. 3). In other words, the shape of the first fastening portion 12 is not deformed after turning. The facing surface 10a of the first fastening portion 12 extends in parallel along an imaginary plane H perpendicular to the rotation axis O. Although not shown, the second fastening portion 13 also extends linearly in a direction perpendicular to the rotation axis O. As shown in FIG.

図２に示すように、補強部用隅部３２は、非硬化処理領域４１と、硬化処理領域４２と、を有している。図４に示すように、硬化処理領域４２を形成するための高周波焼き入れは、外輪本体５の外周面５ａとフランジ１０の反対面１０ｂに跨って設けられている。なお、硬化処理領域４２の硬化層は、外輪軌道２ａ、２ｂの硬化層９ａ、９ｂと連続しないように、高周波焼き入れが行われている。 As shown in FIG. 2 , the reinforcing corner 32 has a non-hardened region 41 and a hardened region 42 . As shown in FIG. 4 , the induction hardening for forming the hardened region 42 is provided across the outer peripheral surface 5 a of the outer ring main body 5 and the opposite surface 10 b of the flange 10 . Induction hardening is performed so that the hardened layer of the hardened region 42 is not continuous with the hardened layers 9a and 9b of the outer ring raceways 2a and 2b.

硬化処理領域４２は、高周波焼き入れによりマルテンサイト変態している。つまり、硬化処理領域４２は、熱処理前よりも体積が０．３～０．４％増加し、図４の矢印で示す方向に膨張している。これにより、硬化処理領域４２は、硬化処理前には平面であった補強部２０に対し、軸方向内側に傾倒するような応力を与えている。この結果、補強部２０は、旋削後、第１締結部１２と同じように、回転軸Ｏと直交する方向に直線状に延在したものの、熱処理後、径方向外側に離隔するにつれて軸方向内側に傾倒するように変形している。そして、補強部２０の対向面１０ａは、締結部１１の対向面１０ａよりも軸方向内側に突出している（図４のフランジ１０の仮想線を参照）。なお、補強部２０の突出量は、特に限定されないが、大きくて数十μｍ程度である。 The hardened region 42 is transformed into martensite by induction hardening. That is, the hardened region 42 has a volume increased by 0.3 to 0.4% compared to before the heat treatment, and expands in the direction indicated by the arrow in FIG. As a result, the hardened region 42 applies stress to the reinforcing portion 20, which was flat before the hardening treatment, so as to tilt it inward in the axial direction. As a result, after turning, the reinforcing portion 20 extends linearly in the direction orthogonal to the rotation axis O in the same way as the first fastening portion 12. It is deformed so that it leans toward The facing surface 10a of the reinforcing portion 20 protrudes further inward in the axial direction than the facing surface 10a of the fastening portion 11 (see the phantom line of the flange 10 in FIG. 4). Although the amount of protrusion of the reinforcing portion 20 is not particularly limited, it is approximately several tens of μm at most.

図２に示すように、補強部用隅部３２における硬化処理領域４２の割合は、１／３から１／２の範囲である。そして、硬化処理領域４２は、補強部用隅部３２の周方向の中央部に位置している（図２の基準線Ｎ１とＮ２とを参照）。よって、補強部２０の周方向の中央部は、軸方向内側に傾倒している。一方で、補強部用隅部３２の非硬化処理領域４１は、補強部用隅部３２の周方向の両端部に位置している。よって、補強部２０の周方向の端部は、回転軸Ｏと直交する方向に直線状に延在している。言い換えると、補強部２０の周方向の端部が軸方向内側に傾倒していないため、隣り合う締結部１１も軸方向内側に傾倒していない。 As shown in FIG. 2, the proportion of the hardened region 42 in the reinforcement corner 32 ranges from 1/3 to 1/2. The hardened region 42 is located in the circumferential center of the reinforcing corner 32 (see reference lines N1 and N2 in FIG. 2). Therefore, the central portion in the circumferential direction of the reinforcing portion 20 is tilted inward in the axial direction. On the other hand, the non-hardened regions 41 of the reinforcement corner 32 are located at both ends of the reinforcement corner 32 in the circumferential direction. Therefore, the circumferential end of the reinforcing portion 20 extends linearly in the direction perpendicular to the rotation axis O. As shown in FIG. In other words, since the circumferential ends of the reinforcing portions 20 are not tilted axially inward, the adjacent fastening portions 11 are also not tilted axially inward.

図２に示すように、隅部３０は、４つの硬化処理領域４２を有している。４つの硬化処理領域４２のうち２つの硬化処理領域４２は、回転軸Ｏから視て一対の第１補強部２１、２１と重なっている。よって、一対の第１補強部２１、２１は、周方向の中央部が軸方向内側へ傾いている。また、残りの２つの硬化処理領域４２は、回転軸Ｏから視て一対の第２補強部２２、２２と重なっている。よって、一対の第２補強部２２、２２は、周方向の中央部が軸方向内側へ傾いている。 As shown in FIG. 2, corner 30 has four hardened areas 42 . Two hardened regions 42 out of the four hardened regions 42 overlap the pair of first reinforcing portions 21 , 21 when viewed from the rotation axis O. As shown in FIG. Therefore, the pair of first reinforcing portions 21, 21 are inclined inward in the axial direction at the central portions in the circumferential direction. The remaining two hardened regions 42 overlap the pair of second reinforcing portions 22, 22 when viewed from the rotation axis O. As shown in FIG. Therefore, the pair of second reinforcing portions 22, 22 are inclined inward in the axial direction at their circumferential central portions.

次に実施形態１に係るハブユニット軸受１の効果を説明する。実施形態１の補強部２０は、締結部１１よりも軸方向内側に突出している。このため、フランジ１０とナックル５０との締結により、フランジ１０の第１締結部１２及び第２締結部１３がナックル５０側へ変形しても、補強部２０の対向面１０ａがナックル５０の取り付け面５２に確実に当接する。 Next, effects of the hub unit bearing 1 according to Embodiment 1 will be described. The reinforcing portion 20 of the first embodiment protrudes further inward in the axial direction than the fastening portion 11 . Therefore, even if the first fastening portion 12 and the second fastening portion 13 of the flange 10 are deformed toward the knuckle 50 by fastening the flange 10 and the knuckle 50, the opposing surface 10a of the reinforcing portion 20 is the attachment surface of the knuckle 50. 52 securely.

また、ナックル５０に当接する４つの補強部２０のうち一対の第１補強部２１、２１は、回転軸Ｏを挟んで車両の前後方向に分かれて配置される。よって、外輪２は、ナックル５０に対してトー角方向Ｔ（図２の矢印Ｔ参照）にがたつくことがない。つまり、ナックル５０と外輪２とのトー角方向Ｔの結合剛性が向上する。 A pair of the first reinforcing portions 21, 21 among the four reinforcing portions 20 abutting on the knuckle 50 are arranged separately in the front-rear direction of the vehicle with the rotation axis O interposed therebetween. Therefore, the outer ring 2 does not rattle with respect to the knuckle 50 in the toe angle direction T (see arrow T in FIG. 2). That is, the joint rigidity in the toe angle direction T between the knuckle 50 and the outer ring 2 is improved.

また、ナックル５０に当接する４つの補強部２０のうち一対の第２補強部２２、２２は、回転軸Ｏを挟んで車両の上下方向に分かれて配置される。よって、外輪２は、ナックル５０に対してキャンバー角方向Ｋ（図２の矢印Ｋ参照）にがたつくことがない。つまり、ナックル５０と外輪２とのキャンバー角方向Ｋの結合剛性が向上する。 Further, the pair of second reinforcing portions 22, 22 among the four reinforcing portions 20 that contact the knuckle 50 are arranged separately in the vertical direction of the vehicle with the rotation axis O interposed therebetween. Therefore, the outer ring 2 does not rattle with respect to the knuckle 50 in the camber angle direction K (see arrow K in FIG. 2). That is, the joint rigidity in the camber angle direction K between the knuckle 50 and the outer ring 2 is improved.

以上、第１実施形態のハブユニット軸受１は、外輪２と、外輪２に回転自在なハブ３と、外輪２とハブ３との間に配置された複数の転動体４と、を備える。外輪２は、筒状の外輪本体５と、外輪本体５の外周面５ａから突出し、かつナックル５０との締結後にナックル５０と対向する対向面１０ａ、及び対向面１０ａと反対側の反対面１０ｂを有するフランジ１０と、外輪本体５の外周面５ａと、フランジ１０の反対面１０ｂと、が交わる隅部３０と、を有する。フランジ１０は、ナックル５０と締結される複数の締結部１１と、複数の締結部１１の間で周方向に延在する複数の補強部２０と、を有する。隅部３０は、周方向の一部を熱処理してなる硬化処理領域４２の第１隅部でと、周方向の残部であり、熱処理が回避された非硬化処理領域４１の第２隅部と、を有する。締結部１１は、ハブ３の回転軸Ｏから視て第２隅部と重なり、回転軸Ｏと直交する方向に延在している。少なくとも１つ以上の補強部２０は、回転軸Ｏから視て周方向の一部が第１隅部と重なり、径方向外側に離隔するにつれて反対面１０ｂから対向面１０ａの方に傾斜している。 As described above, the hub unit bearing 1 of the first embodiment includes the outer ring 2 , the hub 3 rotatable on the outer ring 2 , and the plurality of rolling elements 4 arranged between the outer ring 2 and the hub 3 . The outer ring 2 includes a cylindrical outer ring main body 5, a facing surface 10a that protrudes from the outer peripheral surface 5a of the outer ring main body 5 and faces the knuckle 50 after fastening with the knuckle 50, and an opposite surface 10b on the opposite side of the facing surface 10a. and a corner portion 30 where the outer peripheral surface 5a of the outer ring main body 5 and the opposite surface 10b of the flange 10 intersect. The flange 10 has a plurality of fastening portions 11 fastened to the knuckles 50 and a plurality of reinforcing portions 20 extending in the circumferential direction between the fastening portions 11 . The corner 30 is a first corner of a hardened region 42 formed by heat-treating a portion of the circumferential direction, and a second corner of the non-hardened region 41, which is the rest of the circumferential direction and avoids heat treatment. , has The fastening portion 11 overlaps the second corner when viewed from the rotation axis O of the hub 3 and extends in a direction orthogonal to the rotation axis O. As shown in FIG. At least one or more reinforcement portions 20 partially overlap the first corner portion in the circumferential direction when viewed from the rotation axis O, and are inclined from the opposite surface 10b toward the opposite surface 10a as they are separated radially outward. .

フランジ１０とナックル５０との締結の際、補強部の対向面は、ナックルの取り付け面に確実に当接する。よって、外輪とナックルとの結合剛性を向上させることができる。また、機械加工で、補強部２０を締結部１１よりもナックル５０側に突出させた場合、高コストとなるが、熱処理であるため低コストを図れる。 When the flange 10 and the knuckle 50 are fastened together, the facing surface of the reinforcing portion reliably abuts the mounting surface of the knuckle. Therefore, it is possible to improve the joint rigidity between the outer ring and the knuckle. Also, if the reinforcing portion 20 is made to protrude toward the knuckle 50 side from the fastening portion 11 by machining, the cost is high, but the cost can be reduced because of the heat treatment.

第１実施形態のハブユニット軸受１において、複数の締結部１１は、ナックル５０の上部と締結される一対の第１締結部１２、１２と、ナックル５０の下部と締結される一対の第２締結部１３、１３と、を備える。複数の補強部２０は、第１締結部１２と第２締結部１３との間で延在する一対の第１補強部２１、２１と、一対の第１締結部１２、１２の間と、一対の第２締結部１３、１３の間と、で延在する一対の第２補強部２２、２２と、を有している。一対の第１補強部２１、２１は、回転軸Ｏから視て周方向の一部が硬化処理領域４２の第１隅部と重なっている。 In the hub unit bearing 1 of the first embodiment, the plurality of fastening portions 11 includes a pair of first fastening portions 12, 12 fastened to the upper portion of the knuckle 50 and a pair of second fastening portions fastened to the lower portion of the knuckle 50. and a portion 13, 13. The plurality of reinforcing portions 20 includes a pair of first reinforcing portions 21, 21 extending between the first fastening portion 12 and the second fastening portion 13, a pair of first fastening portions 12, 12, a pair of and a pair of second reinforcing portions 22 , 22 extending between and between the second fastening portions 13 , 13 . A part of the pair of first reinforcing parts 21 , 21 in the circumferential direction when viewed from the rotation axis O overlaps the first corner of the hardening treatment area 42 .

以上から、外輪２とナックル５０とにおけるトー角方向Ｔの結合剛性が向上する。 As described above, the coupling rigidity in the toe angle direction T between the outer ring 2 and the knuckle 50 is improved.

第１実施形態のハブユニット軸受１において、複数の締結部１１は、ナックル５０の上部と締結される一対の第１締結部１２、１２と、ナックル５０の下部と締結される一対の第２締結部１３、１３と、を備える。複数の補強部２０は、第１締結部１２と第２締結部１３との間で延在する一対の第１補強部２１、２１と、一対の第１締結部１２、１２の間と、一対の第２締結部１３、１３の間と、で延在する一対の第２補強部２２、２２と、を有している。一対の第２補強部２２、２２は、回転軸Ｏから視て周方向の一部が非硬化処理領域４１の第１隅部と重なっている。 In the hub unit bearing 1 of the first embodiment, the plurality of fastening portions 11 includes a pair of first fastening portions 12, 12 fastened to the upper portion of the knuckle 50 and a pair of second fastening portions fastened to the lower portion of the knuckle 50. and a portion 13, 13. The plurality of reinforcing portions 20 includes a pair of first reinforcing portions 21, 21 extending between the first fastening portion 12 and the second fastening portion 13, a pair of first fastening portions 12, 12, a pair of and a pair of second reinforcing portions 22 , 22 extending between and between the second fastening portions 13 , 13 . A part of the pair of second reinforcing portions 22 , 22 in the circumferential direction when viewed from the rotation axis O overlaps the first corner portion of the non-hardening treatment area 41 .

以上から、外輪２とナックル５０とにおけるキャンバー角方向Ｋの結合剛性が高くなる。 As described above, the coupling rigidity in the camber angle direction K between the outer ring 2 and the knuckle 50 is increased.

（実施形態２）
図５は、図５は、実施形態２に係る外輪のみを抽出して軸方向外側から視た図である。なお、以下の説明においては、上述した実施形態１で説明したものと同じ構成要素には同一の符号を付して重複する説明は省略する。実施形態２に係る外輪２Ａにおいて、隅部３０に設けられた硬化処理領域４２が４つから２つに減少した点で、実施形態１の外輪２と相違する。 (Embodiment 2)
FIG. 5 is a view of only the outer ring according to Embodiment 2, which is extracted and viewed from the outside in the axial direction. In the following description, the same reference numerals are assigned to the same components as those described in the first embodiment, and overlapping descriptions are omitted. The outer ring 2A according to the second embodiment differs from the outer ring 2 of the first embodiment in that the number of hardened regions 42 provided at the corner 30 is reduced from four to two.

硬化処理領域４２は、回転軸Ｏから視て、一対の第１補強部２１、２１の周方向の中央部と重なっている。また、一対の第１補強部２１、２１は、径方向外側に離隔するにつれて軸方向内側に傾倒している。以上から、一対の第１補強部２１、２１は、締結部１１よりも第１方向内側Ｘ１側に突出している。外輪２とナックル５０とにおけるトー角方向Ｔの結合剛性を向上させることができる。なお、一対の第２補強部２２、２２は、回転軸Ｏから視て、非硬化処理領域４１のみを有する補強部用隅部３２と重なっている。よって、一対の第２補強部２２、２２は、回転軸Ｏと直交する方向に直線状に延在している。 The hardened region 42 overlaps with the central portion of the pair of first reinforcing portions 21 , 21 in the circumferential direction when viewed from the rotation axis O. As shown in FIG. Also, the pair of first reinforcing portions 21, 21 tilts inward in the axial direction as they are separated radially outward. As described above, the pair of first reinforcing portions 21 , 21 protrude toward the inner side X<b>1 in the first direction from the fastening portion 11 . The coupling rigidity in the toe angle direction T between the outer ring 2 and the knuckle 50 can be improved. Note that the pair of second reinforcing portions 22 , 22 overlaps the reinforcing portion corner portion 32 having only the non-hardened region 41 when viewed from the rotation axis O. As shown in FIG. Therefore, the pair of second reinforcing portions 22 , 22 extends linearly in a direction orthogonal to the rotation axis O.

（実施形態３）
図６は、図６は、実施形態３に係る外輪のみを抽出して軸方向外側から視た図である。実施形態３に係る外輪２Ｂにおいて、隅部３０に設けられた硬化処理領域４２が４つから２つに減少した点で、実施形態１の外輪２と相違する。 (Embodiment 3)
FIG. 6 is a view of only the outer ring according to Embodiment 3 extracted and viewed from the outside in the axial direction. The outer ring 2B according to the third embodiment is different from the outer ring 2 of the first embodiment in that the number of hardened regions 42 provided at the corner 30 is reduced from four to two.

硬化処理領域４２は、回転軸Ｏから視て、一対の第２補強部２２、２２の周方向の中央部と重なっている。また、一対の第２補強部２２、２２は、径方向外側に離隔するにつれて軸方向内側に傾倒している。以上から、一対の第２補強部２２、２２は、締結部１１よりも軸方向内側に突出している。外輪２とナックル５０とにおけるキャンバー角方向Ｋの結合剛性を向上させることができる。なお、一対の第１補強部２１、２１は、回転軸Ｏから視て、非硬化処理領域４１のみを有する補強部用隅部３２と重なっている。よって、一対の第１補強部２１、２１は、回転軸Ｏと直交する方向に直線状に延在している。 The hardened region 42 overlaps with the central portion of the pair of second reinforcing portions 22 , 22 in the circumferential direction when viewed from the rotation axis O. Also, the pair of second reinforcing portions 22, 22 tilts inward in the axial direction as they are spaced apart radially outward. As described above, the pair of second reinforcing portions 22 , 22 protrude axially inward from the fastening portion 11 . The coupling rigidity in the camber angle direction K between the outer ring 2 and the knuckle 50 can be improved. Note that the pair of first reinforcing portions 21 , 21 overlaps the reinforcing portion corner portion 32 having only the non-hardened region 41 when viewed from the rotation axis O. As shown in FIG. Therefore, the pair of first reinforcing portions 21, 21 extend linearly in a direction perpendicular to the rotation axis O. As shown in FIG.

（実施形態４）
図７は、図７は、実施形態４に係る外輪のみを抽出して軸方向外側から視た図である。実施形態４に係る外輪２Ｃにおいて、第１締結部１２の個数が２つから１つに減少している点で、実施形態２の外輪２Ａと相違する。 (Embodiment 4)
FIG. 7 is a view of only the outer ring according to Embodiment 4, which is extracted and viewed from the outside in the axial direction. The outer race 2C according to the fourth embodiment differs from the outer race 2A according to the second embodiment in that the number of first fastening portions 12 is reduced from two to one.

詳細には、複数の締結部１１は、ナックル５０の上部と締結される１つの第１締結部１２と、ナックル５０の下部と締結される一対の第２締結部１３、１３と、を備える。複数の補強部２４は、第１締結部１２と第２締結部１３との間で延在する一対の第１補強部２５と、一対の第２締結部１３、１３の間で延在する１つの第２補強部２６と、を有している。また、一対の第１補強部２５、２５における周方向の中央部は、回転軸Ｏから視て周方向の一部が硬化処理領域４２の第１隅部と重なっている。これにより、一対の第１補強部２１、２１の周方向の中央部は、締結部１１よりも軸方向内側に突出している。 Specifically, the plurality of fastening portions 11 includes one first fastening portion 12 fastened to the upper portion of the knuckle 50 and a pair of second fastening portions 13 , 13 fastened to the lower portion of the knuckle 50 . The plurality of reinforcement portions 24 includes a pair of first reinforcement portions 25 extending between the first fastening portion 12 and the second fastening portion 13 and a pair of first reinforcement portions 25 extending between the pair of second fastening portions 13 , 13 . and two second reinforcing portions 26 . In addition, a circumferential center portion of the pair of first reinforcing portions 25 , 25 partially overlaps the first corner portion of the hardened region 42 when viewed from the rotation axis O. As shown in FIG. As a result, the circumferential center portions of the pair of first reinforcing portions 21 , 21 protrude further inward in the axial direction than the fastening portion 11 .

また、一対の第１補強部２５、２５は、車両の側面方向から視た場合、回転軸Ｏを挟んで前後方向に分かれて配置される。よって、外輪２Ｃとナックル５０とを締結した場合、外輪２Ｃは、ナックル５０に対してトー角方向Ｔ（図７の矢印Ｔ参照）にがたつくことがない。つまり、ナックル５０と外輪２とのトー角方向Ｔの結合剛性が向上する。 Further, the pair of first reinforcing portions 25, 25 are arranged separately in the front-rear direction with the rotation axis O interposed therebetween when viewed from the side direction of the vehicle. Therefore, when the outer ring 2C and the knuckle 50 are fastened together, the outer ring 2C does not rattle with respect to the knuckle 50 in the toe angle direction T (see arrow T in FIG. 7). That is, the joint rigidity in the toe angle direction T between the knuckle 50 and the outer ring 2 is improved.

以上、実施形態について説明したが、本開示のハブユニット軸受は、上記した例に限定されない。補強部用隅部３２における硬化処理領域４２の割合は、上記した割合に限定されない。また、硬化処理領域４２の生成は、高周波焼き入れに限定されない。実施形態において、１つの硬化処理領域４２は、周方向に連続して形成されているが、周方向に点在するようにしてもよい。本開示の硬化処理領域４２は、フランジ１０を傾倒させることができればよく、硬化処理されている領域の大きさや深さについて特に限定されない。 Although the embodiments have been described above, the hub unit bearing of the present disclosure is not limited to the above examples. The proportion of the hardened region 42 in the reinforcing corner 32 is not limited to the proportion described above. Moreover, the generation of the hardened region 42 is not limited to induction hardening. In the embodiment, one hardened region 42 is formed continuously in the circumferential direction, but may be scattered in the circumferential direction. The hardened region 42 of the present disclosure is not particularly limited as long as the flange 10 can be tilted, and the size and depth of the hardened region are not particularly limited.

１ハブユニット軸受
２、２Ａ、２Ｂ、２Ｃ外輪
３ハブ
４転動体
５外輪本体
１０フランジ
１０ａ対向面
１０ｂ反対面
１１締結部
１２第１締結部
１３第２締結部
２０、２４補強部
２１、２５第１補強部
２２、２６第２補強部
３０隅部
３１締結部用隅部
３２補強部用隅部
４１非硬化処理領域（第２隅部）
４２硬化処理領域（第１隅部）
５０ナックル
Ｌ１仮想接線 1 Hub Unit Bearing 2, 2A, 2B, 2C Outer Ring 3 Hub 4 Rolling Element 5 Outer Ring Body 10 Flange 10a Opposing Surface 10b Opposing Surface 11 Fastening Portion 12 First Fastening Portion 13 Second Fastening Portion 20, 24 Reinforcing Portion 21, 25 Second 1 reinforcing part 22, 26 second reinforcing part 30 corner 31 corner for fastening part 32 corner for reinforcing part 41 non-hardened area (second corner)
42 hardened area (first corner)
50 Knuckle L1 Virtual tangent

Claims

an outer ring;
a hub rotatable on the outer ring;
a plurality of rolling elements arranged between the outer ring and the hub;
with
The outer ring is
a cylindrical outer ring main body;
a flange that protrudes from the outer peripheral surface of the outer ring main body and has an opposing surface that faces the knuckle after fastening with the knuckle, and an opposite surface that is opposite to the opposing surface;
a corner where the outer peripheral surface of the outer ring main body and the opposite surface of the flange intersect;
has
The flange is
a plurality of fastening portions to be fastened to the knuckle;
a plurality of reinforcing portions extending in the circumferential direction between the plurality of fastening portions;
has
The corner is
a first corner formed by heat-treating a part of the circumferential direction;
a second corner that is the remainder of the circumferential direction and avoids heat treatment;
has
the fastening portion overlaps the second corner when viewed from the rotation axis of the hub and extends in a direction orthogonal to the rotation axis;
At least one or more of the reinforcement portions partially overlap the first corner portion in the circumferential direction when viewed from the rotation shaft, and are inclined from the opposite surface toward the opposite surface as they are separated radially outward. There are hub unit bearings.

The plurality of fastening parts are
a pair of first fastening parts fastened to the upper part of the knuckle;
a pair of second fastening parts fastened to the lower part of the knuckle;
with
The plurality of reinforcing parts are
a pair of first reinforcing portions extending between the first fastening portion and the second fastening portion;
a pair of second reinforcing portions extending between the pair of first fastening portions and between the pair of second fastening portions;
has
2 . The hub unit bearing according to claim 1 , wherein the pair of first reinforcing portions partly overlap with the first corner portion in the circumferential direction when viewed from the rotating shaft.

The plurality of fastening parts are
a pair of first fastening parts fastened to the upper part of the knuckle;
a pair of second fastening parts fastened to the lower part of the knuckle;
with
The plurality of reinforcing parts are
a pair of first reinforcing portions extending between the first fastening portion and the second fastening portion;
a pair of second reinforcing portions extending between the pair of first fastening portions and between the pair of second fastening portions;
has
3 . The hub unit bearing according to claim 1 , wherein the pair of second reinforcing portions partly overlap with the first corner portion in the circumferential direction when viewed from the rotating shaft.

The plurality of fastening parts are
one first fastening part fastened to the upper part of the knuckle;
a pair of second fastening parts fastened to the lower part of the knuckle;
with
The plurality of reinforcing parts are
a pair of first reinforcing portions extending between the first fastening portion and the second fastening portion;
one second reinforcing portion extending between the pair of second fastening portions;
has
2 . The hub unit bearing according to claim 1 , wherein the pair of first reinforcing portions partly overlap with the first corner portion in the circumferential direction when viewed from the rotating shaft.