JP3850709B2

JP3850709B2 - Method for forming bearing boss in metal disk

Info

Publication number: JP3850709B2
Application number: JP2001326396A
Authority: JP
Inventors: 洋行出牛
Original assignee: Nihon Isued Co Ltd
Current assignee: Nihon Isued Co Ltd
Priority date: 2001-10-24
Filing date: 2001-10-24
Publication date: 2006-11-29
Anticipated expiration: 2021-10-24
Also published as: JP2003126918A

Description

【０００１】
【発明の属する技術分野】
本発明は、金属製円板の板面に軸受けボスを成形する金属製円板における軸受けボスの成形方法に関する。
【０００２】
【従来の技術】
最近、軽量化や製造の容易さから、１枚の金属製円板で製造するプーリー、電磁クラッチローター、トルクリミッター、歯車等が多く提案されている。かかるプーリーや歯車等に軸受けボスを設ける方法として、
（ａ）金属製円板とは別個に軸受けボスを鋳造や鍛造等で作り、金属製円板に軸受けボスを溶接などの固着手段を用いて固着する方法、
（ｂ）金属製円板に軸受けボスを、プレス等で一体に絞り出す方法、
等が知られている。
【０００３】
【発明が解決しようとする課題】
しかしながら、（ａ）の方法では、金属製円板と軸受けボスを別個に作りこれを溶接等の固定手段で固定するので、手間がかかりコスト高となってしまい、また、プーリー全体の重量が重く、また軸受けボスが金属製円板から脱落する恐れがあるといった問題点がある。
また、（ｂ）の方法では、工程数が多いことからコスト高となってしまい、また軸受けボスの肉厚化が困難であるといった問題点がある。
【０００４】
本発明の目的は、金属製円板の板面から軸受けボスが脱落するおそれがなく、軸受けボスの肉厚の調整が可能で、低コストで簡単に成形できる金属製円板における軸受けボスの成形方法を提供することにある。
【０００５】
【課題を解決するための手段】
上記目的を達成するために、請求項１に記載の金属製円板における軸受けボスの成形方法は、金属製円板の中央部を、プレス或いはスピニングなどで板厚方向にカップ状に押し出してカップ状部を形成し、該カップ状部の底部を切除して開口し、成形すべきボスの内径に応じた外径からなるボス内面成形部を有し前記カップ状部に挿入されてその先端部を底部に開口した開口部からカップ状部外に突出する成形凸部と、前記カップ状部を形成した金属製円板の一面を支持する支持面とを備えた受型で、前記金属製円板に形成された前記カップ状部に前記成形凸部を挿入するとともに金属製円板の一面を支持面で支持し、前記受型で支持された金属製円板のカップ状部の底部に当接し押圧する押圧面と前記カップ状部の底部に開口した開口部からカップ状部外に突出する成形凸部に嵌合する嵌合穴を備えた押圧型で、前記カップ状部外に突出する成形凸部に嵌合穴を嵌合するとともに押圧面をカップ状部の底部に当接させて、該押圧型と前記受型とで前記金属製円板を両側から挟持して該金属製円板をその中心を軸心として回転させ、前記受型で支持された金属製円板の他面に摺接する摺接面を一側に有し外周面に成形すべきボスの高さに応じた幅を有するボス外面成形面を備えた回転自在のローラダイスをもって、該ローラダイスの摺接面を前記回転する金属製円板の他面に摺接させ、前記ローラダイスのボス外面成形面を前記カップ状部の外周面に押し当てて前記金属製円板の回転と伴回りするローラダイスを前記金属製円板の回転中心側に移動させるとともに押圧型を受型側に移動させて、前記カップ状部を、前記受型に備えた成形凸部のボス内面成形部と前記押圧型の押圧面と前記ローラダイスのボス外面成形面とで加圧して軸受けボスを成形することを特徴とする。
【０００６】
このような金属製円板における軸受けボスの成形方法によれば、金属製円板の中央部を板厚方向にカップ状に押し出してカップ状部を形成し、該カップ状部の底部を切除して開口し、ボス内面成形部を有する成形凸部と金属製円板の一面を支持する支持面を備えた受型で、前記金属製円板に形成された前記カップ状部に前記成形凸部を挿入するとともに金属製円板の一面を支持面で支持し、前記カップ状部の底部に当接し押圧する押圧面と前記カップ状部の開口部からカップ状部外に突出する成形凸部に嵌合する嵌合穴を備えた押圧型で、前記カップ状部外に突出する成形凸部に嵌合穴を嵌合するとともに押圧面をカップ状部の底部に当接させて、該押圧型と前記受型とで前記金属製円板を両側から挟持して該金属製円板をその中心を軸心として回転させ、前記受型で支持された金属製円板の他面に摺接する摺接面を一側に有し外周面に成形すべきボスの高さに応じた幅を有するボス外面成形面を備えた回転自在のローラダイスをもって、該ローラダイスの摺接面を前記回転する金属製円板の他面に摺接させ、前記ローラダイスのボス外面成形面を前記カップ状部の外周面に押し当てて前記金属製円板の回転と伴回りするローラダイスを前記金属製円板の回転中心側に移動させるとともに押圧型を受型側に移動させて、前記カップ状部を、前記受型に備えた成形凸部のボス内面成形部と前記押圧型の押圧面と前記ローラダイスのボス外面成形面とで加圧して軸受けボスを成形するので、金属製円板に一体として堅牢な軸受けボスを、低コストで簡単に成形することができ、しかも、成形すべき軸受けボスの高さに対し、金属製円板の中央部に形成されるカップ状部の高さを所定の高さに設定することにより、求める肉厚の軸受けボスを成形することができる。
【０００７】
請求項２に記載の金属製円板における軸受けボスの成形方法は、金属製円板の中央部を、プレス或いはスピニングなどで板厚方向にカップ状に押し出してカップ状部を形成し、該カップ状部の底部を内向き鍔部を残して開口し、成形すべきボスの内径に応じた外径からなるボス内面成形部と該ボス内面成形部より小径で前記カップ状部の底部に開口した開口部からカップ状部外に突出する小径部とからなり、ボス内面成形部と小径部との段部を鍔受部とした成形凸部と、前記カップ状部を形成した金属製円板の一面を支持する支持面とを備えた受型で、前記金属製円板に形成された前記カップ状部に前記成形凸部を挿入するとともに金属製円板の一面を支持面で支持し、前記受型で支持された金属製円板のカップ状部の底部に当接し押圧する押圧面と前記カップ状部の底部に開口した開口部からカップ状部外に突出する成形凸部の小径部に嵌合する嵌合穴を備えた押圧型で、前記カップ状部外に突出する成形凸部に嵌合穴を嵌合するとともに押圧面をカップ状部の底部に当接させて、該押圧型と前記受型とで前記金属製円板を両側から挟持して該金属製円板をその中心を軸心として回転させ、前記受型で支持された金属製円板の他面に摺接する摺接面を一側に有し外周面に成形すべきボスの高さに応じた幅を有するボス外面成形面を備えた回転自在のローラダイスをもって、該ローラダイスの摺接面を前記回転する金属製円板の他面に摺接させ、前記ローラダイスのボス外面成形面を前記カップ状部の外周面に押し当てて前記金属製円板の回転と伴回りするローラダイスを前記金属製円板の回転中心側に移動させるとともに押圧型を受型側に移動させて、前記カップ状部を、前記受型に備えた成形凸部のボス内面成形部及び鍔受部と前記押圧型の押圧面と前記ローラダイスのボス外面成形面とで加圧して軸受けボスを成形することを特徴とする。
【０００８】
このような金属製円板における軸受けボスの成形方法によれば、金属製円板の中央部を板厚方向にカップ状に押し出してカップ状部を形成し、該カップ状部の底部を内向き鍔部を残して開口し、ボス内面成形部と小径部とからなり、ボス内面成形部と小径部との段部を鍔受部とした成形凸部と、前記金属製円板の一面を支持する支持面を備えた受型で、前記金属製円板に形成された前記カップ状部に前記成形凸部を挿入するとともに金属製円板の一面を支持面で支持し、前記カップ状部の底部に当接し押圧する押圧面と前記カップ状部の底部に開口した開口部からカップ状部外に突出する成形凸部の小径部に嵌合する嵌合穴を備えた押圧型で、前記カップ状部外に突出する成形凸部に嵌合穴を嵌合するとともに押圧面をカップ状部の底部に当接させて、該押圧型と前記受型とで前記金属製円板を両側から挟持して該金属製円板をその中心を軸心として回転させ、前記受型で支持された金属製円板の他面に摺接する摺接面を一側に有し外周面に成形すべきボスの高さに応じた幅を有するボス外面成形面を備えた回転自在のローラダイスをもって、該ローラダイスの摺接面を前記回転する金属製円板の他面に摺接させ、前記ローラダイスのボス外面成形面を前記カップ状部の外周面に押し当てて前記金属製円板の回転と伴回りするローラダイスを前記金属製円板の回転中心側に移動させるとともに押圧型を受型側に移動させて、前記カップ状部を、前記受型に備えた成形凸部のボス内面成形部及び鍔受部と前記押圧型の押圧面と前記ローラダイスのボス外面成形面とで加圧して軸受けボスを成形するので、金属製円板に一体として堅牢な鍔付きの軸受けボスを、低コストで簡単に成形することができ、しかも、成形すべき軸受けボスの高さに対し、金属製円板の中央部に形成されるカップ状部の高さを所定の高さに設定することにより、求める肉厚の軸受けボスを成形することができる。
【０００９】
【発明の実施の形態】
以下、図面に基づき本発明の実施の形態の一例を説明する。
図１〜図３及び図５〜図７は本発明に係る金属製円板における軸受けボスの成形方法の実施の形態の第１例の工程図、図４は中央部にカップ状部が形成された金属製円板の断面図、図８は第１例の方法で製造された軸受けボス付きの金属製円板の断面図である。
【００１０】
まず、図１に示すように、下部をベースプレート１に支持された円柱状プレス内型２と該円柱状プレス内型２の外周に摺動自在に嵌合し、スプリング３により上方に付勢された受型４とからなる下型５と、前記円柱状プレス内型２と同軸上に位置し該円柱状プレス内型２との間に所定の隙間を形成する内径のプレス孔６を有し円柱状プレス内型２に挿入されるプレス外型７と、プレス外型７のプレス孔６内に摺動自在に嵌合しスプリング８により下方に付勢される押え型９とからなる上型１０との間に、金属板をプレス加工等により打ち抜いた金属製円板１１をセットする。
【００１１】
そして、プレス機（不図示）により上型１０を下型５側に移動させ、上型１０のプレス外型７を下型５の円柱状プレス内型２に挿入することにより、金属製円板１１の中央部を板厚方向にカップ状に押し出してカップ状部１２を形成する（図２）。このとき金属製円板１１の中央部を板厚方向に形成されたカップ状部１２の高さは、成形すべき軸受けボスの肉厚により設定されるもので、カップ状部１２の高さを、成形すべき軸受けボスの高さより高くすれば、その分が軸受けボスの肉厚側に移行し、軸受けボスの肉厚化が図れる。本例では成形すべき軸受けボスの高さよりも高く設定されている。
【００１２】
次に、図３に示すようにカップ状部１２内に下型５にセットしたポンチ１３を挿入し、該カップ状部１２の底部側から上型１０にセットしたダイス型１４を押し込み、カップ状部１２の底部を抜き打ち切除して開口する。このようにして底部に開口部１５を有するカップ状部１２が形成された金属製円板１１を図４に示す。
【００１３】
次に、かかるカップ状部１２を形成したカップ状部１２が形成された金属製円板１１を受型１６で支持する。受型１６は成形すべきボスの内径に応じた外径からなるボス内面成形部１７を有し、金属製円板１１のカップ状部１２に挿入される成形凸部１８と、カップ状部１２を形成した金属製円板１１の一面を支持する支持面１９を有する凹部２０とを備えていて、金属製円板１１に形成されたカップ状部１２に成形凸部１８を挿入してその先端部を底部に開口した開口部１５からカップ状部１２外に突出させるとともに、凹部２０に金属製円板１１を嵌め込み支持面１９で金属製円板１１の一面を支持する。
【００１４】
このようにして受型１６で支持された金属製円板１１の他面側を押圧型２１で支持し、押圧型２１と前記受型１６とで金属製円板１１を両側から挟持する。前記押圧型２１は一面を受型１６の支持面１９で支持された金属製円板１１のカップ状部１２の底部に当接し押圧する押圧面２２とカップ状部１２の底部に開口した開口部１５からカップ状部１２外に突出する成形凸部１８に嵌合する嵌合穴２３を備えていて、前記カップ状部１２に突出する成形凸部１８に嵌合穴２３を嵌合するとともに押圧面２２をカップ状部１２の底部に当接させて金属製円板１１の他面側を支持するようになっている。このようにして、押圧型２１と前記受型１６とで金属製円板１１を両側から挟持し、該押圧型２１と受型１６を回転させて金属製円板１１をその中心を軸心として回転させる（図５）。
【００１５】
次に、一面を受型１６の支持面１９で支持された金属製円板１１の他面に摺接する摺接面２４を一側に有し、該摺接面２４と直角に交差する外周面に成形すべきボスの高さに応じた幅を有するボス外面成形面２５を備え、回転自在に支持されているローラダイス２６を金属製円板１１の他面と平行に移動させて前記成形凸部１８に近づけ、受型１６の支持面１９で一面を支持された金属製円板１１の他面に摺接面２４を摺接させ、回転する金属製円板１１と伴回りするローラダイス２６のボス外面成形面２５を前記カップ状部１２の外周面２７に押し当てて金属製円板１１の回転中心側に移動させるとともに押圧型２１を受型１６側に移動させ（図６）、カップ状部１２を、受型１６に備えた成形凸部１８のボス内面成形部１７と押圧型２１の押圧面２２とローラダイス２６のボス外面成形面２５とで加圧する（図７）。
【００１６】
この時、カップ状部１２は成形すべき軸受けボスの高さよりも高くなっているので、カップ状部１２を、受型１６に備えた成形凸部１８のボス内面成形部１７と押圧型２１の押圧面２２とローラダイス２６のボス外面成形面２５とで加圧することにより、カップ状部１２の、成形すべき軸受けボスの高さより高い部分が軸受けボスの肉厚に移行し、カップ状部１２が増肉して肉厚の軸受けボス２８が成形される。
【００１７】
これにより、金属製円板１１の中央部に金属製円板１１と一体となって突出する肉厚の軸受けボス２８が成形され、図８に示すような軸受けボス２８付きの金属製円板１１が得られる。
【００１８】
図９〜図１５は本発明に係る金属製円板１１における軸受けボスの成形方法の実施の形態の第２例を示したもので、図９、図１０及び図１２〜図１４は本例の金属製円板１１における軸受けボスの成形方法の工程図、図１１は中央部にカップ状部１２が形成された金属製円板１１の断面図、図１５は第２例の方法で製造された軸受けボス付きの金属製円板１１の断面図である。
【００１９】
本例においては、先ず、図９に示すように、下部をベースプレート３０に支持され、内部に中空部３１を有し該中空部３１と外部とを連通する連通孔３２を先端面に有する円柱状プレス内型３３と、該円柱状プレス内型３３の外周に摺動自在に嵌合し、ベースプレート３０の孔３４，３５に摺動自在に嵌合する支柱３６，３７によって支持されている受型３８とからなる下型３９と、前記円柱状プレス内型３３と同軸上に位置し円柱状プレス内型３３との間に所定の隙間を形成する内径のプレス孔４０を有し円柱状プレス内型３３に挿入されるプレス外型４１と、ポンチ４２を挿通する挿通孔４３を有するとともに、プレス外型４１のプレス孔４０内に摺動自在に嵌合し、スプリング４４により下方に付勢される押え型４５とからなる上型４６との間に、金属板をプレス加工等により打ち抜いた金属製円板１１をセットする。
【００２０】
そして、プレス機（不図示）により上型４６を該上型４６の押え型４５が金属製円板１１に当接するまで下型３９側に移動させるとともに上型４６を構成するプレス外型４１により下型３９の受型３８を下方に移動させる。これによって円柱状プレス内型３３が金属製円板１１の中央部を板厚方向にカップ状に押し出し、カップ状部１２を形成する。このとき金属製円板１１の中央部を板厚方向に形成されたカップ状部１２の高さは、成形すべき軸受けボスの高さよりも高く設定されている。
【００２１】
次に、図１０に示すように、ポンチ４２が円柱状プレス内型３３の連通孔３２に嵌合してカップ状部１２の底部を内向き鍔部４７を残して打ち抜き切除し、開口する。このようにして底部に開口部１５を有するカップ状部１２が形成された金属製円板１１を図１１に示す。
【００２２】
次に、かかるカップ状部１２を形成した金属製円板１１を受型１６で支持する。受型１６は成形すべきボスの内径に応じた外径からなるボス内面成形部１７と該ボス内面成形部１７より小径でカップ状部１２の底部に開口した開口部１５からカップ状部１２外に突出する小径部４８とからなり、ボス内面成形部１７と小径部４８との段部を鍔受部４９とした成形凸部１８と、カップ状部１２を形成した金属製円板１１の一面を支持する支持面１９を有する凹部２０とを備えていて、金属製円板１１に形成されたカップ状部１２に成形凸部１８を挿入してその先端部を底部に開口した開口部１５からカップ状部１２外に突出させるとともに、凹部２０に金属製円板１１を嵌め込み支持面１９で金属製円板１１の一面を支持する。
【００２３】
このようにして受型１６で支持された金属製円板１１の他面側を押圧型２１で支持し、受型１６と押圧型２１とで金属製円板１１を両側から挟持する。前記押圧型２１は一面を受型１６の支持面１９で支持された金属製円板１１のカップ状部１２の底部の内向き鍔部４７に当接し押圧する押圧面２２とカップ状部１２の底部に開口した開口部１５からカップ状部１２外に突出する成形凸部１８の小径部４８に嵌合する嵌合穴２３を備えていて、前記カップ状部１２外に突出する成形凸部１８に嵌合穴２３を嵌合するとともに押圧面２２をカップ状部１２の底部に当接させて金属製円板１１の他面側を支持するようになっている。このようにして、該押圧型２１と受型１６を回転させて金属製円板１１をその中心を軸心として回転させる（図１２）。
【００２４】
次に、一面を受型１６の支持面１９で支持された金属製円板１１の他面に摺接する摺接面２４を一側に有し、該摺接面２４と直角に交差する外周面に成形すべきボスの高さに応じた幅を有するボス外面成形面２５を備え、回転自在に支持されたローラダイス２６を金属製円板１１の他面と平行に移動させて前記成形凸部１８に近づけ、受型１６の支持面１９で一面を支持された金属製円板１１の他面に摺接面２４を摺接させ、回転する金属製円板１１と伴回りするローラダイス２６のボス外面成形面２５を前記カップ状部１２の外周面２７に押し当てて金属製円板１１の回転中心側に移動させるとともに押圧型２１を受型１６側に移動させ（図１３）、カップ状部１２を、前記受型１６に備えた成形凸部１８のボス内面成形部１７及び鍔受部４９と前記押圧型２１の押圧面２２と前記ローラダイス２６のボス外面成形面２５とで加圧する（図１４）。
【００２５】
この時、カップ状部１２は成形すべき軸受けボスの高さよりも高くなっているので、カップ状部１２を、受型１６に備えた成形凸部１８のボス内面成形部１７及び鍔受部４９と押圧型２１の押圧面２２とローラダイス２６のボス外面成形面２５とで加圧することにより、内向き鍔部４７を有する肉厚の軸受けボス５０が成形される。
【００２６】
これにより、金属製円板１１の中央部に金属製円板１１と一体となって突出する肉厚の軸受けボス５０が成形され、図１５に示すような内向き鍔部４７を有する軸受けボス付きの金属製円板１１が得られる。
【００２７】
【発明の効果】
以上のように請求項１，２に記載の金属製円板における軸受けボスの成形方法によると、金属製円板に一体として堅牢な軸受けボスを、低コストで簡単に成形することができ、しかも、成形すべき軸受けボスの高さに対し、金属製円板の中央部に形成されるカップ状部の高さを所定の高さに設定することにより、求める肉厚の軸受けボスを成形することができる。
【図面の簡単な説明】
【図１】本発明に係る金属製円板における軸受けボスの成形方法の実施の形態の第１例の工程図である。
【図２】本発明に係る金属製円板における軸受けボスの成形方法の実施の形態の第１例の工程図である。
【図３】本発明に係る金属製円板における軸受けボスの成形方法の実施の形態の第１例の工程図である。
【図４】図１乃至図３の工程で中央部にカップ状部が形成された金属製円板の断面図である。
【図５】本発明に係る金属製円板における軸受けボスの成形方法の実施の形態の第１例の工程図である。
【図６】本発明に係る金属製円板における軸受けボスの成形方法の実施の形態の第１例の工程図である。
【図７】本発明に係る金属製円板１１における軸受けボスの成形方法の実施の形態の第１例の工程図である。
【図８】第１例の方法で製造された軸受けボス付きの金属製円板を示す断面図である。
【図９】本発明に係る金属製円板における軸受けボスの成形方法の実施の形態の第２例の工程図である。
【図１０】本発明に係る金属製円板における軸受けボスの成形方法の実施の形態の第２例の工程図である。
【図１１】図９，図１０の工程で中央部にカップ状部が形成された金属製円板の断面図である。
【図１２】本発明に係る金属製円板における軸受けボスの成形方法の実施の形態の第２例の工程図である。
【図１３】本発明に係る金属製円板における軸受けボスの成形方法の実施の形態の第２例の工程図である。
【図１４】本発明に係る金属製円板における軸受けボスの成形方法の実施の形態の第２例の工程図である。
【図１５】第２例の方法で製造された軸受けボス付きの金属製円板を示す断面図である。
【符号の説明】
１，３０ベースプレート
２，３３円柱状プレス内型
３，８，４４スプリング
４，３８受型
５，３９下型
６，４０プレス孔
７，４１プレス外型
９，４５押え型
１０，４６上型
１１金属製円板
１２カップ状部
１３，４２ポンチ
１４ダイス型
１５開口部
１６受型
１７ボス内面成形部
１８成形凸部
１９支持面
２０凹部
２１押圧型
２２押圧面
２３嵌合穴
２４摺接面
２５ボス外面成形面
２６ローラダイス
２７外周面
２８軸受けボス
３１中空部
３２連通孔
３４，３５孔
３６，３７支柱
４３挿通孔
４７内向き鍔部
４８小径部
４９鍔受部
５０軸受けボス[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for forming a bearing boss in a metal disc for forming a bearing boss on the plate surface of the metal disc.
[0002]
[Prior art]
Recently, many pulleys, electromagnetic clutch rotors, torque limiters, gears, and the like that are manufactured from a single metal disk have been proposed for weight reduction and ease of manufacture. As a method of providing a bearing boss on such a pulley or gear,
(A) A method of making a bearing boss separately from the metal disk by casting or forging, and fixing the bearing boss to the metal disk by using a fixing means such as welding,
(B) A method of squeezing the bearing boss on the metal disk integrally with a press,
Etc. are known.
[0003]
[Problems to be solved by the invention]
However, in the method (a), since the metal disk and the bearing boss are separately formed and fixed by fixing means such as welding, it takes time and cost, and the weight of the entire pulley is heavy. Also, there is a problem that the bearing boss may fall off the metal disk.
Further, the method (b) has a problem in that the number of steps is large and the cost is high, and it is difficult to increase the thickness of the bearing boss.
[0004]
An object of the present invention is to form a bearing boss in a metal disc that can be easily formed at low cost, without the risk of the bearing boss dropping off from the plate surface of the metal disc, allowing adjustment of the thickness of the bearing boss. It is to provide a method.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the method for forming a bearing boss in a metal disk according to claim 1 is characterized in that the center part of the metal disk is extruded into a cup shape in the plate thickness direction by pressing or spinning or the like. Forming a cup-shaped part, opening the bottom part of the cup-shaped part by opening, and having a boss inner surface molded part having an outer diameter corresponding to the inner diameter of the boss to be molded, and being inserted into the cup-shaped part. The metal circle is a receiving die provided with a molding convex part projecting outside the cup-shaped part from the opening part opened to the bottom part, and a support surface supporting one surface of the metal disk forming the cup-shaped part. The molding convex portion is inserted into the cup-shaped portion formed on the plate, and one surface of the metal disk is supported by a support surface, and the bottom of the cup-shaped portion of the metal disk supported by the receiving mold is contacted. The pressing surface that touches and presses and the opening that opens at the bottom of the cup-shaped part A pressing die provided with a fitting hole that fits into a molding convex portion that protrudes outside the cup-shaped portion. The pressing hole is fitted into the molding convex portion that projects outside the cup-shaped portion and the pressing surface is cup-shaped portion. The metal disk is sandwiched from both sides by the pressing mold and the receiving mold, and the metal disk is rotated about its center as an axis, and is supported by the receiving mold. A rotatable roller die having a boss outer surface forming surface having a slidable contact surface on one side and a width corresponding to the height of the boss to be formed on the outer peripheral surface on one side, the slidable contact surface contacting the other surface of the metal disk, The sliding contact surface of the roller die is brought into sliding contact with the other surface of the rotating metal disk, and the boss outer surface forming surface of the roller die is pressed against the outer peripheral surface of the cup-shaped portion to rotate the metal disk. The accompanying roller die is moved to the rotation center side of the metal disc and the pressing die is moved to the receiving die side. The cup-shaped portion is pressed by the boss inner surface forming portion of the forming convex portion provided in the receiving die, the pressing surface of the pressing die, and the boss outer surface forming surface of the roller die to form the bearing boss. It is characterized by that.
[0006]
According to such a method for forming a bearing boss in a metal disk, the center part of the metal disk is extruded in a cup shape in the plate thickness direction to form a cup-shaped part, and the bottom of the cup-shaped part is cut off. And a mold having a boss inner surface formed portion and a support surface for supporting one surface of the metal disk, and the formed convex portion on the cup-shaped portion formed on the metal disk. And a pressing surface that contacts and presses the bottom of the cup-shaped portion and a molding convex portion that protrudes outside the cup-shaped portion from the opening of the cup-shaped portion. A pressing die having a fitting hole to be fitted, the fitting hole is fitted to the molding convex portion protruding outside the cup-shaped portion, and the pressing surface is brought into contact with the bottom portion of the cup-shaped portion. The metal disc is sandwiched from both sides by the receiving mold and the metal disc is centered on the center. Boss outer surface molding surface having a slidable contact surface on one side and slidably contacting the other surface of the metal disk supported by the receiving mold and having a width corresponding to the height of the boss to be molded on the outer peripheral surface A slidable contact surface of the roller die with the other surface of the rotating metal disk, and a boss outer surface molding surface of the roller die is placed on the outer peripheral surface of the cup-shaped portion. The roller die that is pressed and rotated with the rotation of the metal disk is moved to the rotation center side of the metal disk and the pressing mold is moved to the receiving mold side, and the cup-shaped portion is moved to the receiving mold. The bearing boss is molded by pressurizing with the boss inner surface molding portion of the molding convex portion, the pressing surface of the pressing die and the boss outer surface molding surface of the roller die, so that the bearing boss is solid and integrated with the metal disk. Can be easily molded at low cost, By setting the height of the cup-shaped part formed in the center part of the metal disc to a predetermined height with respect to the height of the bearing boss to be formed, it is possible to form a bearing boss with a desired thickness it can.
[0007]
The method for forming a bearing boss in a metal disc according to claim 2 is a method of forming a cup-shaped portion by extruding a central portion of the metal disc in a cup shape in a plate thickness direction by pressing or spinning. The bottom part of the cup-shaped part is opened leaving the inwardly facing flange part, and the boss inner surface molded part having an outer diameter corresponding to the inner diameter of the boss to be molded and the bottom of the cup-shaped part having a smaller diameter than the boss inner surface molded part A small-diameter portion projecting out of the cup-shaped portion from the opening, a molding convex portion having a step portion of the boss inner surface molded portion and the small-diameter portion as a flange portion, and a metal disc forming the cup-shaped portion A receiving die having a supporting surface for supporting one surface, inserting the molding convex portion into the cup-shaped portion formed on the metal disk, and supporting one surface of the metal disk with a supporting surface, Abuts and presses against the bottom of the cup-shaped part of the metal disc supported by the receiving mold Molding that protrudes out of the cup-shaped part with a pressing die with a fitting hole that fits into the small diameter part of the molding convex part that projects out of the cup-shaped part from the pressure surface and the opening that opens in the bottom of the cup-shaped part A fitting hole is fitted into the convex portion and the pressing surface is brought into contact with the bottom of the cup-shaped portion, and the metal disc is sandwiched from both sides by the pressing die and the receiving die. Rotating around the center, the width corresponding to the height of the boss to be formed on the outer peripheral surface having a sliding contact surface on one side that contacts the other surface of the metal disk supported by the receiving mold A rotatable roller die having a boss outer surface forming surface having a sliding contact surface of the roller die with the other surface of the rotating metal disk, and the boss outer surface forming surface of the roller die being the cup A roller die that presses against the outer peripheral surface of the metal portion and rotates with the rotation of the metal disk. The cup-shaped part is moved to the center of rotation of the disc and the pressing mold is moved to the receiving mold side. The bearing boss is formed by applying pressure between the pressing surface and the boss outer surface forming surface of the roller die.
[0008]
According to such a method for forming a bearing boss in a metal disk, the center part of the metal disk is extruded in a cup shape in the thickness direction to form a cup-shaped part, and the bottom of the cup-shaped part is directed inward Opening leaving the flange part, consisting of a boss inner surface molded part and a small diameter part, and supporting the molding convex part with the step part of the boss inner surface molded part and the small diameter part as a receiving part, and one surface of the metal disk A receiving die having a supporting surface for inserting the molding convex portion into the cup-shaped portion formed on the metal disk and supporting one surface of the metal disk with a supporting surface, A pressing die having a pressing surface that contacts and presses the bottom and a fitting hole that fits into a small diameter portion of a molding convex portion that protrudes outside the cup-shaped portion from an opening opened at the bottom of the cup-shaped portion. Fit the fitting hole into the convex part that protrudes out of the cup and press the pressing surface against the bottom of the cup. The metal disk is sandwiched from both sides by the pressing mold and the receiving mold, and the metal disk is rotated about its center, and the metal disk supported by the receiving mold A rotatable roller die having a boss outer surface molding surface having a sliding contact surface on one side and a width corresponding to the height of the boss to be molded on the outer peripheral surface. A roller die that slides in contact with the other surface of the rotating metal disk and presses the outer surface of the boss of the roller die against the outer peripheral surface of the cup-shaped part to rotate with the rotation of the metal disk. Are moved to the rotation center side of the metal disc and the pressing die is moved to the receiving side, and the cup-shaped portion is formed with a boss inner surface forming portion and a hook receiving portion of the forming convex portion provided in the receiving die, The bearing die is pressed by pressing the pressing surface of the pressing mold and the boss outer surface forming surface of the roller die. As a result, it is possible to easily form a bearing boss with a strong flange integrally with a metal disk at a low cost, and the height of the bearing boss to be molded is less than that of the metal disk. By setting the height of the cup-shaped part formed in the center part to a predetermined height, it is possible to form a bearing boss having a desired thickness.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings.
1 to 3 and 5 to 7 are process diagrams of a first example of an embodiment of a method for forming a bearing boss in a metal disk according to the present invention, and FIG. 4 is a cup-shaped part formed in the center part. FIG. 8 is a sectional view of a metal disk with a bearing boss manufactured by the method of the first example.
[0010]
First, as shown in FIG. 1, the lower part of the cylindrical press inner mold 2 supported by the base plate 1 and the outer periphery of the cylindrical press inner mold 2 are slidably fitted and urged upward by the spring 3. A lower die 5 comprising a receiving die 4 and a press hole 6 having an inner diameter that is positioned coaxially with the cylindrical press inner die 2 and forms a predetermined gap between the cylindrical press inner die 2. An upper die comprising a press outer die 7 inserted into the cylindrical press inner die 2 and a presser die 9 slidably fitted in the press hole 6 of the press outer die 7 and biased downward by a spring 8. 10 is set with a metal disk 11 in which a metal plate is punched out by press working or the like.
[0011]
Then, the upper die 10 is moved to the lower die 5 side by a press machine (not shown), and the press outer die 7 of the upper die 10 is inserted into the columnar press inner die 2 of the lower die 5, thereby making a metal disk. The center part of 11 is extruded in a cup shape in the plate thickness direction to form a cup-like part 12 (FIG. 2). At this time, the height of the cup-shaped portion 12 formed in the thickness direction at the center of the metal disk 11 is set by the thickness of the bearing boss to be molded. If the height of the bearing boss to be molded is made higher, the portion shifts to the thickness side of the bearing boss, and the thickness of the bearing boss can be increased. In this example, it is set higher than the height of the bearing boss to be molded.
[0012]
Next, as shown in FIG. 3, the punch 13 set in the lower mold 5 is inserted into the cup-shaped part 12, and the die mold 14 set in the upper mold 10 is pushed in from the bottom side of the cup-shaped part 12. The bottom of the part 12 is punched and cut open. FIG. 4 shows the metal disk 11 having the cup-like portion 12 having the opening 15 at the bottom in this way.
[0013]
Next, the metal disk 11 on which the cup-shaped part 12 on which the cup-shaped part 12 is formed is supported by the receiving die 16. The receiving die 16 has a boss inner surface molding portion 17 having an outer diameter corresponding to the inner diameter of the boss to be molded, a molding convex portion 18 inserted into the cup-shaped portion 12 of the metal disk 11, and the cup-shaped portion 12. And a concave portion 20 having a support surface 19 that supports one surface of the metal disk 11 formed with the metal disk 11, and a molding convex part 18 is inserted into the cup-shaped part 12 formed on the metal disk 11 and its tip The metal disk 11 is fitted into the recess 20 and the support surface 19 supports one surface of the metal disk 11 while projecting the part from the opening 15 opened at the bottom.
[0014]
In this way, the other surface side of the metal disc 11 supported by the receiving die 16 is supported by the pressing die 21, and the metal disc 11 is sandwiched from both sides by the pressing die 21 and the receiving die 16. The pressing mold 21 has one surface abutting on and pressing against the bottom of the cup-shaped portion 12 of the metal disk 11 supported by the support surface 19 of the receiving mold 16 and an opening opening at the bottom of the cup-shaped portion 12. 15 is provided with a fitting hole 23 that fits into the molding convex portion 18 projecting out of the cup-shaped portion 12 from 15, and the fitting hole 23 is fitted into the molding convex portion 18 projecting into the cup-shaped portion 12 and pressed. The surface 22 is brought into contact with the bottom of the cup-shaped portion 12 to support the other surface side of the metal disk 11. In this way, the metal disc 11 is sandwiched from both sides by the pressing die 21 and the receiving die 16, and the pressing die 21 and the receiving die 16 are rotated so that the metal disc 11 is centered on the center thereof. Rotate (Figure 5).
[0015]
Next, an outer peripheral surface having one surface having a sliding contact surface 24 that is in sliding contact with the other surface of the metal disk 11 supported by the support surface 19 of the receiving die 16 and intersecting the sliding contact surface 24 at a right angle. A boss outer surface molding surface 25 having a width corresponding to the height of the boss to be molded is provided, and a roller die 26 that is rotatably supported is moved in parallel with the other surface of the metal disk 11 to thereby form the molding convexity. A roller die 26 that is brought close to the portion 18, is brought into sliding contact with the other surface of the metal disk 11 that is supported by the support surface 19 of the receiving die 16, and is rotated with the rotating metal disk 11. The boss outer surface molding surface 25 is pressed against the outer peripheral surface 27 of the cup-shaped portion 12 and moved to the rotation center side of the metal disc 11 and the pressing die 21 is moved to the receiving die 16 side (FIG. 6). The boss inner surface forming portion 17 of the forming convex portion 18 provided in the receiving die 16 and the pressing die 21 Pressurized with a boss exterior surface molding surface 25 of the pressing surface 22 and the roller die 26 (FIG. 7).
[0016]
At this time, since the cup-shaped portion 12 is higher than the height of the bearing boss to be molded, the cup-shaped portion 12 is formed between the boss inner surface molded portion 17 of the molding convex portion 18 provided in the receiving die 16 and the pressing die 21. By applying pressure between the pressing surface 22 and the boss outer surface molding surface 25 of the roller die 26, the portion of the cup-shaped portion 12 that is higher than the height of the bearing boss to be molded shifts to the thickness of the bearing boss, and the cup-shaped portion 12 The thickness of the bearing boss 28 is increased.
[0017]
As a result, a thick bearing boss 28 protruding integrally with the metal disk 11 is formed at the center of the metal disk 11, and the metal disk 11 with the bearing boss 28 as shown in FIG. Is obtained.
[0018]
9 to 15 show a second example of the embodiment of the method for forming the bearing boss in the metal disk 11 according to the present invention. FIGS. 9, 10 and 12 to 14 show the example of this example. FIG. 11 is a cross-sectional view of a metal disk 11 having a cup-shaped part 12 formed at the center, and FIG. 15 is manufactured by the method of the second example. It is sectional drawing of the metal disc 11 with a bearing boss | hub.
[0019]
In this example, first, as shown in FIG. 9, a cylindrical shape having a lower portion supported by a base plate 30, a hollow portion 31 inside, and a communication hole 32 communicating the hollow portion 31 and the outside at the tip surface. A press inner die 33 and a receiving die supported by support columns 36 and 37 slidably fitted on the outer periphery of the cylindrical press inner die 33 and slidably fitted in holes 34 and 35 of the base plate 30. A press die 40 having an inner diameter that is positioned coaxially with the cylindrical press inner die 33 to form a predetermined gap between the lower press 39 and the cylindrical press inner die 33. The press outer die 41 inserted into the die 33 and the insertion hole 43 through which the punch 42 is inserted are slidably fitted into the press hole 40 of the press outer die 41 and are urged downward by a spring 44. Upper mold 4 consisting of the presser mold 45 Between the sets of metal discs 11 punched out of the metal plate by press working or the like.
[0020]
Then, the upper die 46 is moved to the lower die 39 side by a press machine (not shown) until the presser die 45 of the upper die 46 comes into contact with the metal disk 11 and the press outer die 41 constituting the upper die 46 is used. The receiving mold 38 of the lower mold 39 is moved downward. As a result, the cylindrical press inner mold 33 pushes the central portion of the metal disk 11 in a cup shape in the plate thickness direction to form the cup-shaped portion 12. At this time, the height of the cup-shaped portion 12 formed at the center of the metal disk 11 in the thickness direction is set higher than the height of the bearing boss to be molded.
[0021]
Next, as shown in FIG. 10, the punch 42 is fitted into the communication hole 32 of the cylindrical press inner mold 33, and the bottom of the cup-shaped portion 12 is punched and cut away leaving the inward flange portion 47 and opened. FIG. 11 shows the metal disk 11 in which the cup-shaped portion 12 having the opening 15 at the bottom is formed in this way.
[0022]
Next, the metal disk 11 on which the cup-shaped portion 12 is formed is supported by the receiving die 16. The receiving die 16 has an outer diameter corresponding to the inner diameter of the boss to be molded and a boss inner surface molding portion 17 and an opening 15 which is smaller in diameter than the boss inner surface molding portion 17 and opens at the bottom of the cup-shaped portion 12. The convex surface 18 of the metal boss 11 formed with the cup-shaped portion 12 and the molding convex portion 18 having the step portion of the boss inner surface molded portion 17 and the small diameter portion 48 as the flange portion 49. And a recess 20 having a support surface 19 for supporting the metal, and a molding convex portion 18 is inserted into a cup-shaped portion 12 formed on the metal disk 11 and the tip portion thereof is opened from the opening 15 at the bottom. While projecting out of the cup-shaped portion 12, the metal disk 11 is fitted into the recess 20 and one surface of the metal disk 11 is supported by the support surface 19.
[0023]
In this way, the other surface side of the metal disk 11 supported by the receiving mold 16 is supported by the pressing mold 21, and the metal disk 11 is clamped from both sides by the receiving mold 16 and the pressing mold 21. The pressing mold 21 has one surface that is in contact with and presses the inward flange 47 at the bottom of the cup-shaped portion 12 of the metal disk 11 supported by the support surface 19 of the receiving mold 16. The molding convex part 18 which has the fitting hole 23 which fits into the small diameter part 48 of the shaping | molding convex part 18 which protrudes out of the cup-shaped part 12 from the opening part 15 opened to the bottom part protrudes out of the said cup-shaped part 12. The fitting hole 23 is fitted to the pressing portion 22 and the pressing surface 22 is brought into contact with the bottom of the cup-shaped portion 12 to support the other surface side of the metal disk 11. In this way, the pressing die 21 and the receiving die 16 are rotated to rotate the metal disk 11 around the center thereof (FIG. 12).
[0024]
Next, an outer peripheral surface having one surface having a sliding contact surface 24 that is in sliding contact with the other surface of the metal disk 11 supported by the support surface 19 of the receiving die 16 and intersecting the sliding contact surface 24 at a right angle. A boss outer surface molding surface 25 having a width corresponding to the height of the boss to be molded is provided, and a roller die 26 rotatably supported is moved in parallel with the other surface of the metal disk 11 to form the molding convex portion. The roller die 26 is moved along with the rotating metal disc 11 by bringing the sliding contact surface 24 into sliding contact with the other surface of the metal disc 11 supported on one surface by the support surface 19 of the receiving die 16. The boss outer surface molding surface 25 is pressed against the outer peripheral surface 27 of the cup-shaped portion 12 and moved to the rotation center side of the metal disk 11 and the pressing die 21 is moved to the receiving die 16 side (FIG. 13), and the cup shape is obtained. The boss inner surface forming portion 17 and the hook receiving portion of the forming convex portion 18 provided with the portion 12 as the receiving die 16. Pressurized with 9 and the pressing surface 22 of the pressing mold 21 and the boss outer surface molding surface 25 of the roller die 26 (FIG. 14).
[0025]
At this time, since the cup-shaped portion 12 is higher than the height of the bearing boss to be molded, the cup-shaped portion 12 is formed on the boss inner surface molded portion 17 and the collar receiving portion 49 of the molded convex portion 18 provided in the receiving mold 16. By pressing with the pressing surface 22 of the pressing die 21 and the boss outer surface forming surface 25 of the roller die 26, a thick bearing boss 50 having an inward flange 47 is formed.
[0026]
As a result, a thick bearing boss 50 protruding integrally with the metal disk 11 is formed at the center of the metal disk 11, and with a bearing boss having an inward flange 47 as shown in FIG. The metal disk 11 is obtained.
[0027]
【The invention's effect】
As described above, according to the method for forming a bearing boss in a metal disk according to claims 1 and 2, it is possible to easily form a robust bearing boss integrally with the metal disk at a low cost. By setting the height of the cup-shaped part formed in the center part of the metal disk to a predetermined height with respect to the height of the bearing boss to be molded, the bearing boss having a desired thickness is formed. Can do.
[Brief description of the drawings]
FIG. 1 is a process diagram of a first example of an embodiment of a method for forming a bearing boss in a metal disc according to the present invention.
FIG. 2 is a process diagram of a first example of an embodiment of a method for forming a bearing boss in a metal disc according to the present invention.
FIG. 3 is a process diagram of a first example of an embodiment of a method for forming a bearing boss in a metal disk according to the present invention.
4 is a cross-sectional view of a metal disk having a cup-shaped portion formed at the center in the steps of FIGS. 1 to 3; FIG.
FIG. 5 is a process diagram of a first example of an embodiment of a method for forming a bearing boss in a metal disc according to the present invention.
FIG. 6 is a process diagram of a first example of an embodiment of a method for forming a bearing boss in a metal disc according to the present invention.
FIG. 7 is a process diagram of a first example of an embodiment of a method for forming a bearing boss in the metal disk 11 according to the present invention.
FIG. 8 is a cross-sectional view showing a metal disc with a bearing boss manufactured by the method of the first example.
FIG. 9 is a process diagram of a second example of an embodiment of a method for forming a bearing boss in a metal disc according to the present invention.
FIG. 10 is a process diagram of a second example of the embodiment of the method for forming the bearing boss in the metal disk according to the present invention.
11 is a cross-sectional view of a metal disc having a cup-like portion formed in the center in the steps of FIGS. 9 and 10. FIG.
FIG. 12 is a process diagram of a second example of the embodiment of the method for forming the bearing boss in the metal disk according to the present invention.
FIG. 13 is a process diagram of a second example of the embodiment of the method for forming the bearing boss in the metal disk according to the present invention.
FIG. 14 is a process diagram of a second example of the embodiment of the method for forming the bearing boss in the metal disk according to the present invention.
FIG. 15 is a cross-sectional view showing a metal disc with a bearing boss manufactured by the method of the second example.
[Explanation of symbols]
1,30 Base plate 2,33 Cylindrical press inner die 3,8,44 Spring 4,38 Receiving die 5,39 Lower die 6,40 Press hole 7,41 Press outer die 9,45 Presser die 10,46 Upper die 11 Metal disk 12 Cup-shaped portion 13, 42 Punch 14 Die die 15 Opening portion 16 Receiving die 17 Boss inner surface forming portion 18 Molding convex portion 19 Support surface 20 Recess 21 Pressing die 22 Pressing surface 23 Fitting hole 24 Sliding contact surface 25 Boss outer surface molding surface 26 Roller die 27 Outer peripheral surface 28 Bearing boss 31 Hollow portion 32 Communication hole 34, 35 Hole 36, 37 Post 43 Insertion hole 47 Inward flange portion 48 Small diameter portion 49 Bearing portion 50 Bearing boss

Claims

The central part of the metal disk is extruded in a cup shape in the thickness direction by pressing or spinning to form a cup-shaped part, and the bottom of the cup-shaped part is excised and opened,
A molding convex portion that has a boss inner surface molding portion having an outer diameter corresponding to the inner diameter of the boss to be molded, and is inserted into the cup-shaped portion and protrudes out of the cup-shaped portion from an opening having its tip opened at the bottom. And a support die for supporting one surface of the metal disc on which the cup-shaped portion is formed, and the molding convex portion is inserted into the cup-shaped portion formed on the metal disc and the metal Support one side of the disc made with a support surface,
Fits a pressing surface that contacts and presses the bottom of the cup-shaped portion of the metal disk supported by the receiving mold, and a molding convex portion that protrudes outside the cup-shaped portion from the opening opened at the bottom of the cup-shaped portion. A pressing die having a fitting hole to be fitted, the fitting hole is fitted to a molding convex portion protruding outside the cup-shaped portion, and a pressing surface is brought into contact with a bottom portion of the cup-shaped portion; Sandwiching the metal disk from both sides with a receiving mold and rotating the metal disk around its center,
Rotation provided with a boss outer surface forming surface having a sliding contact surface on one side that is in sliding contact with the other surface of the metal disk supported by the receiving mold and having a width corresponding to the height of the boss to be formed on the outer peripheral surface. With a free roller die, the sliding contact surface of the roller die is brought into sliding contact with the other surface of the rotating metal disk, and the boss outer surface forming surface of the roller die is pressed against the outer peripheral surface of the cup-shaped portion. Move the roller die accompanying the rotation of the metal disk to the rotation center side of the metal disk and move the pressing die to the receiving mold side,
The cup-shaped portion is pressed with a boss inner surface molding portion of a molding convex portion provided in the receiving mold, a pressing surface of the pressing die, and a boss outer surface molding surface of the roller die, thereby forming a bearing boss. A method for forming a bearing boss in a metal disk.

The central part of the metal disk is extruded in a cup shape in the thickness direction by pressing or spinning to form a cup-shaped part, and the bottom part of the cup-shaped part is opened leaving an inward flange part,
A boss inner surface molded portion having an outer diameter corresponding to the inner diameter of the boss to be molded, and a small diameter portion that is smaller in diameter than the boss inner surface molded portion and opens to the bottom of the cup-shaped portion and protrudes outside the cup-shaped portion. A receiving projection provided with a forming convex portion having a step portion of the boss inner surface forming portion and the small diameter portion as a flange receiving portion, and a support surface for supporting one surface of the metal disk on which the cup-shaped portion is formed, Inserting the molding convex part into the cup-shaped part formed on the metal disk and supporting one surface of the metal disk with a support surface;
A small diameter portion of the convex portion protruding outside the cup-shaped portion from the pressing surface that contacts and presses the bottom portion of the cup-shaped portion of the metal disc supported by the receiving mold and the opening opened in the bottom portion of the cup-shaped portion. A pressing die having a fitting hole for fitting into the cup, and fitting the fitting hole into the molding convex part protruding outside the cup-shaped part and bringing the pressing surface into contact with the bottom part of the cup-shaped part. The metal disk is sandwiched from both sides by the mold and the receiving mold, and the metal disk is rotated around its center as an axis,
Rotation provided with a boss outer surface forming surface having a sliding contact surface on one side that is in sliding contact with the other surface of the metal disk supported by the receiving mold and having a width corresponding to the height of the boss to be formed on the outer peripheral surface. With a free roller die, the sliding contact surface of the roller die is brought into sliding contact with the other surface of the rotating metal disk, and the boss outer surface forming surface of the roller die is pressed against the outer peripheral surface of the cup-shaped portion. Move the roller die accompanying the rotation of the metal disk to the rotation center side of the metal disk and move the pressing die to the receiving mold side,
The cup-shaped portion is pressed with the boss inner surface forming portion and the hook receiving portion of the forming convex portion provided in the receiving mold, the pressing surface of the pressing die, and the boss outer surface forming surface of the roller die to form a bearing boss. A method for forming a bearing boss in a metal disk.