JP2004058120A - Forming method of spline forging product - Google Patents

Forming method of spline forging product Download PDF

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Publication number
JP2004058120A
JP2004058120A JP2002222707A JP2002222707A JP2004058120A JP 2004058120 A JP2004058120 A JP 2004058120A JP 2002222707 A JP2002222707 A JP 2002222707A JP 2002222707 A JP2002222707 A JP 2002222707A JP 2004058120 A JP2004058120 A JP 2004058120A
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Japan
Prior art keywords
spline
shaft portion
spare
diameter
forming
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
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JP2002222707A
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Japanese (ja)
Inventor
Yoji Inoue
井上　要次
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Musashi Seimitsu Industry Co Ltd
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Musashi Seimitsu Industry Co Ltd
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Priority to JP2002222707A priority Critical patent/JP2004058120A/en
Publication of JP2004058120A publication Critical patent/JP2004058120A/en
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Abstract

<P>PROBLEM TO BE SOLVED: To provide a forming method of spline forging products capable of keeping high size precision for a long time and preventing the occurrence of cracks to the utmost. <P>SOLUTION: The forming method of a spline forging product have an axis part 14 extended to the axis direction, a flange part 15 with larger diameter than that of the axis part at one edge of the axis 14, a connecting corner 10 for connecting the flange part 15 and the axis part 14 is formed with a recessed peripheral shape in the flange part 15 along the axis part, and a spline 9 is formed from the connecting corner 10 to the another edge side of the axis part 14. A spare shaft 4 having an outer diameter smaller than the diameter of a tooth bottom surface 9a of the spline 9, and a spare form product having a spare flange part 5 with a diameter larger than that of the spare shaft 4 are formed beforehand, and the spare shaft 4 is extended the diameter to form the spline 9, and at the same time, the outer circumference part of the spare flange part 5 is projected to the other edge side of the axis part 14 by pressing the spare flange part 5 in the axis direction, and a recessed peripheral connecting corner is formed. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【産業上の利用分野】
本発明は、軸部と、その軸部より大径のフランジ部を有する鍛造品で、軸部にスプラインが成形されるスプライン鍛造品の成形方法に関する。
【０００２】
【従来の技術】
従来より鋼材部品を形成する場合、鍛造成形にて荒成形後、切削加工にて仕上げ成形することが多く行われてきた。ここで鍛造成形は、図５に示す如く、例えば軸線方向に延びる軸部１１４と、その軸部１１４の一端端部に軸部１１４より大径のフランジ部１１５を有し、フランジ部１１５と軸部１１４とをつなぐ連結コーナ１１０が軸部１１４に沿ってフランジ部１１５内部に凹周状に成形され、連結コーナ１１０から軸部１１４の他端端部側にスプライン１０９が、フランジ部１１５の外周側にかさ歯１０８が成形される円筒状のべベルギアＷ１０３（図５の（エ））を形成する場合、まず線材を切断した円柱状の素材Ｗ１００（図５の（ア））を軸線方向に押圧して円盤状の予備成形品Ｗ１０１（図５の（イ））を形成し、続いて予備成形品Ｗ１０１の軸心付近を前方へ押し出し、深穴の凹部１０７を有するカップ状で外周形状が所望するべベルギアＷ１０３と同一形状のスプライン鍛造品Ｗ１０２（図５の（ウ））を形成し、最後にスプライン鍛造品Ｗ１０２の底部１１１を打ち抜いて、貫通孔１１２が成形されるべベルギアＷ１０３を形成していた。
【０００３】
【発明が解決しようとする課題】
上記べベルギアＷ１０３の鍛造成形工程で、特に予備成形品Ｗ１０１からスプライン鍛造品Ｗ１０２を形成する工程では、円盤状の予備成形品Ｗ１０１を前方押し出しにて軸部１１４を成形するが、スプライン鍛造品Ｗ１０２は軸部１１４とフランジ部１１５とをつなぐ連結コーナ１１０が軸部１１４に沿ってフランジ部１１５内部に凹周状に成形されるため、この連結コーナ１１０を成形する金型の連結コーナ成形部は凹周形状に倣った凸周形状となる。この金型を使用して軸部１１４の前方押し出しを行なうと、凸周形状の連結コーナ成形部に沿って前方押し出しの鍛造肉が流動するため、連結コーナ成形部の摩耗が促進され、早期にスプライン鍛造品Ｗ１０２の寸法精度が低下するということがある。
【０００４】
そこで、予備成形品の形状を円柱状とし、円柱状の予備成形品の軸心付近を押圧して軸部を成形後、軸部側からフランジ部側へ鍛造肉を流動させてスプライン鍛造品を形成することも考えられる。この場合、金型の連結コーナ成形部は内周側には突出していないため、連結コーナ成形部の摩耗は、前記軸部１１４側への前方押し出し成形に比べて抑制できる。しかし、軸部成形後、フランジ部を成形すると、軸部のスプラインに成形された鍛造肉がフランジ部側へ流動するため、スプラインの凹凸に沿ってフランジ部に筋状の傷が入り、割れ等の発生の原因となることがある。
【０００５】
従って本発明は上述の如き課題を解決し、高い寸法精度を長期に渡って維持でき、割れ等の発生を極力抑えることのできるスプライン鍛造品の成形方法を提供することを目的とする。
【０００６】
【課題を解決するための手段】
本発明のスプライン鍛造品の成形方法は以下のとおりである。
【０００７】
１　軸線方向に延びる軸部と、軸部の一端端部に軸部より大径のフランジ部を有し、フランジ部と軸部とをつなぐ連結コーナが軸部に沿ってフランジ部内部に凹周状に成形され、連結コーナから軸部の他端端部側にスプラインが成形されるスプライン鍛造品の成形方法において、予めスプラインの歯底面の直径より小径の外径を有する予備軸部と、予備軸部より大径の予備フランジ部を有する予備成形品を形成し、続いて、予備軸部を拡径してスプラインを成形すると同時に、予備フランジ部を軸線方向へ押圧することにより予備フランジ部の外周部を軸部の他端端部側へ突出させ、凹周状の連結コーナを成形する。
【０００８】
２　上記スプライン鍛造品の成形方法において、スプラインは、予備成形品の軸心付近を押圧して凹部を成形することにより、鍛造肉を外周側へ流動させて成形する。
【０００９】
【実施例】
以下、本発明の実施例を図１乃至図４に基づいて説明する。
【００１０】
図１は、軸線方向に延びる軸部１４と、その軸部１４の一端端部に軸部１４より大径のフランジ部１５を有し、フランジ部１５と軸部１４とをつなぐ連結コーナ１０が軸部１４に沿ってフランジ部１５内部に凹周状に成形され、連結コーナ１０から軸部１４の他端端部側にスプライン９が、フランジ部１５の外周側にかさ歯８が成形される円筒状のべベルギアＷ３（図１の（エ））を鍛造成形する工程を表す。まず、線材を切断した円柱状の素材Ｗ０（図１の（ア））を軸線方向に押圧して、所望するスプライン９の歯底面９ａの直径Ｄより小径の外径ｄを有し軸線方向に延びる予備軸部４と、予備軸部４より大径で反予備軸部側が凹む予備凹部６を有する予備フランジ部５とからなる予備成形品Ｗ１（図１の（イ））を形成する。続いて、予備成形品Ｗ１を軸線方向に押圧して、深穴の凹部７を有するカップ状で外周形状が所望するべベルギアＷ３と同一形状のスプライン鍛造品Ｗ２（図１の（ウ））を形成し、最後にスプライン鍛造品Ｗ２の底部１１を打ち抜いて、貫通孔１２が成形されるべベルギアＷ３を形成する。
【００１１】
上記べベルギアＷ３の鍛造成形工程で、特に予備成形品Ｗ１からスプライン鍛造品Ｗ２を形成する工程を図２及び図３に基づいて説明する。
【００１２】
まず、図２に基づいて鍛造装置２０を説明すると、４１は下型で、内周にスプライン９を成形するスプライン成形部５３が形成される下ダイ５１と、下ダイ５１の外周側に配置され下ダイ５１を保持する下ダイホルダ５６と、下ダイ５１の内周側に配置され軸線方向に進退可能な下ノックアウトピン５８と、下ダイ５１及び下ダイホルダ５６を支持する支持ダイス６１とを備える。ここで下ダイ５１には、スプライン成形部５３が上端面より上方へ突出し、この突出部が連結コーナ成形部５５を形成する。また、下ダイ５１のスプライン成形部５３を含む内周面と下ノックアウトピン５８の上面とにより、予備成形品Ｗ１の予備軸部４を投入する下型彫空間５２が画成される。
【００１３】
次に、２１は上型で、内周にかさ歯８を成形するかさ歯成形部２４が形成される上ダイ２２と、上ダイ２２の外周側に配置され上ダイ２２を保持する上ダイホルダ３１と、　上ダイ２２の内周側に配置され上ダイ２２の下端面より下方へ突出するパンチ２６と、パンチ２６の内部に配置され軸線方向に進退可能な上ノックアウトピン２８とを備える。また、上ダイ２２のかさ歯成形部２４を含む内周面とパンチ２６の外周面とにより上型彫空間２３が画成される。
【００１４】
上記鍛造装置２０で予備成形品Ｗ１からスプライン鍛造品Ｗ２を形成する場合、下型４１の下型彫空間５２に予備成形品Ｗ１の予備軸部４を投入し、その後、上型２１を下降させて、図３に示す如く、上型２１のパンチ２６で予備成形品Ｗ１の軸心付近を押圧することにより予備軸部４を拡径してスプライン９を成形すると同時に、上型２１のかさ歯成形部２４を含む上ダイ２２で予備成形品Ｗ１の予備フランジ部５を軸線方向へ押圧することによりかさ歯８及び連結コーナ１０を有するフランジ部１５を成形して、スプライン鍛造品Ｗ２を形成する。
【００１５】
ここで、上記鍛造成形工程における鍛造肉の流れを図４を基に説明すると、まず図４の（ア）は予備成形品Ｗ１を下型４１の下型彫空間５２に投入した状態で、この状態から上型２１を下降させパンチ２６で予備成形品Ｗ１の軸心付近を押圧することにより、図４の（イ）に示す如く、鍛造肉は外周側、つまりスプライン成形部５３に上方から順次外周側へ流動する。そして更に上型２１が下降することにより、図４の（ウ）に示す如く、パンチ２６も下降すると同時に上ダイ２２が予備フランジ部５に当接し押圧を開始する。つまり、予備軸部４の鍛造肉はスプライン成形部５３全てに流動すると同時に、予備フランジ部５の鍛造肉が軸線方向下方へ突出する如く流動し、連結コーナ成形部５５から外周側へ向かってかさ歯８とともにフランジ部１５が成形される。そして、上型２１が所定位置まで下降することにより、図４の（エ）に示す如く、スプライン鍛造品Ｗ２が形成される。
【００１６】
従って、上記スプライン鍛造品の成形方法は、予備軸部４を拡径してスプライン９を成形すると同時に、予備フランジ部５を軸線方向へ押圧することにより予備フランジ部５の外周部を押圧方向へ突出させ、凹周状の連結コーナ１０を成形するため、連結コーナ１０を成形する凸周形状の連結コーナ成形部５５に沿って流動する鍛造肉の量を極力少なくできる。
【００１７】
また、上記スプライン鍛造品の成形方法によれば、スプライン９とかさ歯８も同時に成形できるため、両歯形の位相を所望する位置関係に合わせることができる。
【００１８】
尚、上記実施例では、中実の予備成形品Ｗ１の軸心付近を押圧して凹部７を成形することにより、鍛造肉を外周側へ流動させてスプライン９を成形したが、中空の予備成形品Ｗ１を使用し内径を拡径することにより、鍛造肉を外周側へ流動させてスプライン９を成形しても良い。
【００１９】
【発明の効果】
以上のように本発明のスプライン鍛造品の成形方法によれば、軸線方向に延びる軸部と、軸部の一端端部に軸部より大径のフランジ部を有し、フランジ部と軸部とをつなぐ連結コーナが軸部に沿ってフランジ部内部に凹周状に成形され、連結コーナから軸部の他端端部側にスプラインが成形されるスプライン鍛造品の成形方法において、予めスプラインの歯底面の直径より小径の外径を有する予備軸部と、予備軸部より大径の予備フランジ部を有する予備成形品を形成し、続いて、予備軸部を拡径してスプラインを成形すると同時に、予備フランジ部を軸線方向へ押圧することにより予備フランジ部の外周部を軸部の他端端部側へ突出させ、凹周状の連結コーナを成形するため、連結コーナを成形する凸周形状の連結コーナ成形部に沿って流動する鍛造肉の量を極力少なくできるので、連結コーナ成形部の摩耗を防ぎ、スプライン鍛造品が高い寸法精度を長期に渡って維持でき、更に割れ等の発生を極力抑えることができる。
【００２０】
また、スプラインを、予備成形品の軸心付近を押圧して凹部を成形することにより、鍛造肉を外周側へ流動させて成形すると、容易に予備軸部を拡径できる。
【図面の簡単な説明】
【図１】本発明の成形方法により成形されるスプライン鍛造品を含むべベルギアの鍛造成形工程を表す断面平面図である。
【図２】本発明のスプライン鍛造品の成形方法により鍛造成形する前の状態を表す部分断面平面図である。
【図３】本発明のスプライン鍛造品の成形方法により鍛造成形した後の状態を表す部分断面平面図である。
【図４】本発明のスプライン鍛造品の成形方法により鍛造成形する状態を順次表す要部拡大図である。
【図５】従来の成形方法により成形されるスプライン鍛造品を含むべベルギアの鍛造成形工程を表す断面平面図である。
【符号の説明】
４　予備軸部
５　予備フランジ部
７　凹部
９　スプライン
９ａ　歯底面
１０　連結コーナ
１４　軸部
１５　フランジ部
Ｗ１　予備成形品
Ｄ　（スプラインの歯底面の）直径
ｄ　（予備軸部の）外径[0001]
[Industrial applications]
The present invention relates to a method for forming a spline forged product in which a spline is formed in a shaft portion, the forging having a shaft portion and a flange portion having a larger diameter than the shaft portion.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in the case of forming a steel part, after forming roughly by forging, then finishing by cutting. Here, as shown in FIG. 5, the forging includes, for example, a shaft portion 114 extending in the axial direction, and a flange portion 115 having a larger diameter than the shaft portion 114 at one end of the shaft portion 114. A connecting corner 110 for connecting to the connecting portion 114 is formed in the flange 115 along the shaft 114 so as to have a concave circumference. A spline 109 is formed from the connecting corner 110 to the other end of the shaft 114, and the outer periphery of the flange 115. When forming a cylindrical bevel gear W103 (FIG. 5D) on which a bevel tooth 108 is formed on the side, first, a columnar material W100 (FIG. 5A) obtained by cutting a wire is axially moved. By pressing, a disk-shaped preform W101 (FIG. 5A) is formed, and the vicinity of the axis of the preform W101 is extruded forward. Desired bevel gear 103 the same shape of the spline forgings W102 formed (in FIG. 5 (c)), and finally by punching a bottom 111 of the spline forgings W102, the through hole 112 to form a bevel gear W103 being molded.
[0003]
[Problems to be solved by the invention]
In the forging process of the bevel gear W103, particularly in the process of forming the spline forged product W102 from the preformed product W101, the shaft portion 114 is formed by extruding the disk-shaped preformed product W101 forward, but the spline forged product W102 Since the connecting corner 110 connecting the shaft portion 114 and the flange portion 115 is formed into a concave shape inside the flange portion 115 along the shaft portion 114, the connecting corner forming portion of the mold for forming the connecting corner 110 is The convex peripheral shape follows the concave peripheral shape. When the front portion of the shaft portion 114 is extruded using this mold, the forged meat of the front extruded portion flows along the connection corner forming portion having a convex peripheral shape, so that the wear of the connection corner forming portion is promoted, and The dimensional accuracy of the spline forged product W102 may decrease.
[0004]
Therefore, the shape of the preformed product is made into a cylindrical shape, and the vicinity of the axis of the cylindrical preformed product is pressed to form the shaft portion, and then the forged meat is caused to flow from the shaft portion side to the flange portion to form a spline forged product. It is also conceivable to form. In this case, since the connecting corner forming portion of the mold does not protrude toward the inner peripheral side, the wear of the connecting corner forming portion can be suppressed as compared with the forward extrusion forming to the shaft portion 114 side. However, if the flange is formed after the shank is formed, the forged meat formed on the spline of the shank flows toward the flange, so that a streak-like scratch is formed on the flange along the unevenness of the spline, cracking, etc. It may cause the occurrence of.
[0005]
Accordingly, an object of the present invention is to solve the above-mentioned problems and to provide a method for forming a spline forged product capable of maintaining high dimensional accuracy for a long period of time and suppressing generation of cracks and the like as much as possible.
[0006]
[Means for Solving the Problems]
The method for forming a spline forged product of the present invention is as follows.
[0007]
1 A shaft portion extending in the axial direction, and a flange portion having a larger diameter than the shaft portion at one end of the shaft portion, and a connecting corner connecting the flange portion and the shaft portion has a concave periphery along the shaft portion inside the flange portion. In a method of forming a spline forged product in which a spline is formed from the connecting corner to the other end side of the shaft portion from the connecting corner, a spare shaft portion having an outer diameter smaller than the diameter of the tooth bottom surface of the spline in advance, Forming a preform having a spare flange portion larger in diameter than the shaft portion, then expanding the spare shaft portion to form a spline, and simultaneously pressing the spare flange portion in the axial direction to form the spline. The outer peripheral portion is protruded toward the other end of the shaft portion to form a concave peripheral connecting corner.
[0008]
(2) In the method for forming a spline forged product, the spline is formed by pressing the vicinity of the axis of the preformed product to form a concave portion, thereby causing the forged meat to flow to the outer peripheral side.
[0009]
【Example】
An embodiment of the present invention will be described below with reference to FIGS.
[0010]
FIG. 1 shows a shaft portion 14 extending in the axial direction, and a flange portion 15 having a larger diameter than the shaft portion 14 at one end of the shaft portion 14. A connecting corner 10 connecting the flange portion 15 and the shaft portion 14 is provided. A spline 9 is formed from the connecting corner 10 to the other end of the shaft portion 14, and a bevel 8 is formed on the outer peripheral side of the flange portion 15. This represents a step of forging a cylindrical bevel gear W3 (FIG. 1D). First, a columnar material W0 (FIG. 1A) obtained by cutting a wire is pressed in the axial direction to have an outer diameter d smaller than the diameter D of the tooth bottom surface 9a of the desired spline 9 and has an outer diameter d in the axial direction. A preformed product W1 (FIG. 1 (a)) is formed which includes a preliminary shaft portion 4 extending and a preliminary flange portion 5 having a larger diameter than the preliminary shaft portion 4 and a preliminary concave portion 6 having a concave portion on the side opposite to the preliminary shaft portion. Subsequently, the preform W1 is pressed in the axial direction, and a spline forged product W2 ((c) in FIG. 1) having the same shape as the bevel gear W3 having a desired outer peripheral shape in a cup shape having the deep hole recess 7 is formed. Then, the bottom 11 of the spline forged product W2 is punched out to form a bevel gear W3 in which the through hole 12 is formed.
[0011]
The forging process of the bevel gear W3, in particular, the process of forming the spline forged product W2 from the preformed product W1 will be described with reference to FIGS.
[0012]
First, the forging device 20 will be described with reference to FIG. 2. Reference numeral 41 denotes a lower die, which is disposed on the outer periphery of the lower die 51, in which a spline forming portion 53 for forming the spline 9 is formed on the inner periphery. The lower die 51 includes a lower die holder 56 that holds the lower die 51, a lower knockout pin 58 that is disposed on the inner peripheral side of the lower die 51 and that can move forward and backward in the axial direction, and a support die 61 that supports the lower die 51 and the lower die holder 56. Here, a spline forming portion 53 protrudes upward from the upper end surface of the lower die 51, and the projecting portion forms a connecting corner forming portion 55. Further, the inner peripheral surface including the spline forming portion 53 of the lower die 51 and the upper surface of the lower knockout pin 58 define a lower engraving space 52 into which the preliminary shaft portion 4 of the preform W1 is put.
[0013]
Next, reference numeral 21 denotes an upper die, an upper die 22 having a bevel tooth forming portion 24 for forming the bevel teeth 8 on the inner periphery, and an upper die holder 31 arranged on the outer peripheral side of the upper die 22 for holding the upper die 22. A punch 26 disposed on the inner peripheral side of the upper die 22 and protruding downward from a lower end surface of the upper die 22; and an upper knockout pin 28 disposed inside the punch 26 and capable of moving back and forth in the axial direction. In addition, an upper engraving space 23 is defined by an inner peripheral surface of the upper die 22 including the bevel tooth forming portion 24 and an outer peripheral surface of the punch 26.
[0014]
When forming the spline forged product W2 from the preformed product W1 with the forging device 20, the preliminary shaft portion 4 of the preformed product W1 is put into the lower die engraving space 52 of the lower die 41, and then the upper die 21 is lowered. As shown in FIG. 3, the preshaft 4 is expanded by pressing the vicinity of the axis of the preform W1 with the punch 26 of the upper mold 21 to form the spline 9, and at the same time, the bevel teeth of the upper mold 21 are formed. By pressing the preliminary flange portion 5 of the preformed product W1 in the axial direction with the upper die 22 including the forming portion 24, the flange portion 15 having the bevel teeth 8 and the connecting corners 10 is formed to form the spline forged product W2. .
[0015]
Here, the flow of the forged meat in the forging process will be described with reference to FIG. 4. First, FIG. 4A shows a state in which the preform W1 has been put into the lower engraving space 52 of the lower die 41. By lowering the upper mold 21 from the state and pressing the vicinity of the axis of the preform W1 with the punch 26, the forged meat is sequentially moved from the upper side to the outer peripheral side, that is, the spline forming section 53 as shown in FIG. It flows to the outer peripheral side. When the upper die 21 further descends, as shown in FIG. 4C, the punch 26 also descends, and at the same time, the upper die 22 comes into contact with the preliminary flange portion 5 and starts pressing. In other words, the forged meat of the preliminary shaft portion 4 flows to the entire spline forming portion 53, and at the same time, the forged meat of the preliminary flange portion 5 flows so as to protrude downward in the axial direction, and the bulk of the forged meat from the connecting corner molding portion 55 to the outer peripheral side. A flange 15 is formed together with the teeth 8. Then, as the upper die 21 descends to a predetermined position, a spline forged product W2 is formed as shown in FIG.
[0016]
Accordingly, in the method of forming a spline forged product, the spline 9 is formed by expanding the diameter of the preliminary shaft portion 4 and, at the same time, the outer peripheral portion of the preliminary flange portion 5 is pressed in the pressing direction by pressing the preliminary flange portion 5 in the axial direction. Since the protruding portions are formed to form the concave peripheral connecting corners 10, the amount of forged meat flowing along the convex peripheral connecting corner forming portions 55 for forming the connecting corners 10 can be minimized.
[0017]
In addition, according to the above-described method for forming a spline forged product, the spline 9 and the beveled teeth 8 can be formed at the same time, so that the phases of the two teeth can be adjusted to a desired positional relationship.
[0018]
In the above embodiment, the spline 9 was formed by pressing the vicinity of the axis of the solid preform W1 to form the recess 7 so that the forged meat was allowed to flow to the outer peripheral side, but the hollow preform was formed. The spline 9 may be formed by flowing the forged meat to the outer peripheral side by expanding the inner diameter by using the article W1.
[0019]
【The invention's effect】
As described above, according to the method for forming a spline forged product of the present invention, a shaft portion extending in the axial direction, and a flange portion having a larger diameter than the shaft portion at one end of the shaft portion, the flange portion and the shaft portion In the method of forming a spline forged product, a connecting corner connecting the spline is formed along the shaft portion in a concave circumferential shape inside the flange portion, and a spline is formed from the connecting corner to the other end side of the shaft portion. Forming a preformed product having a spare shaft portion having an outer diameter smaller than the diameter of the bottom surface and a spare flange portion having a larger diameter than the spare shaft portion, and then expanding the spare shaft portion to form a spline, By pressing the auxiliary flange portion in the axial direction, the outer peripheral portion of the auxiliary flange portion is protruded toward the other end of the shaft portion, and a convex peripheral shape is formed to form a concave peripheral connection corner. Flow along the connecting corner Since the amount of forging meat that can minimize the coupling prevents the corner molding part wear, can be maintained over a high dimensional accuracy spline forgings in long, it is possible to further suppress the generation of cracks as much as possible.
[0020]
In addition, when the spline is pressed near the axis of the preformed product to form a concave portion, and the forged meat is caused to flow toward the outer peripheral side, the diameter of the preformed shaft portion can be easily increased.
[Brief description of the drawings]
FIG. 1 is a sectional plan view showing a forging process of a bevel gear including a spline forged product formed by a forming method of the present invention.
FIG. 2 is a partial cross-sectional plan view showing a state before forging by a method for forming a spline forged product of the present invention.
FIG. 3 is a partial cross-sectional plan view showing a state after forging by a method for forming a spline forged product of the present invention.
FIG. 4 is an enlarged view of a main part sequentially showing a state of forging by a method for forming a spline forged product of the present invention.
FIG. 5 is a sectional plan view showing a forging process of a bevel gear including a spline forged product formed by a conventional forming method.
[Explanation of symbols]
4 Preliminary Shaft 5 Preliminary Flange 7 Recess 9 Spline 9a Bottom Surface 10 Connecting Corner 14 Shaft 15 Flange W1 Preformed D Diameter d (of Spline Bottom Surface) Outer Diameter (of Preliminary Shaft)

Claims (2)

軸線方向に延びる軸部（１４）と、該軸部（１４）の一端端部に該軸部（１４）より大径のフランジ部（１５）を有し、該フランジ部（１５）と軸部（１４）とをつなぐ連結コーナ（１０）が軸部（１４）に沿ってフランジ部（１５）内部に凹周状に成形され、該連結コーナ（１０）から軸部（１４）の他端端部側にスプライン（９）が成形されるスプライン鍛造品の成形方法において、予めスプライン（９）の歯底面（９ａ）の直径（Ｄ）より小径の外径（ｄ）を有する予備軸部（４）と、該予備軸部（４）より大径の予備フランジ部（５）を有する予備成形品（Ｗ１）を形成し、続いて、前記予備軸部（４）を拡径してスプライン（９）を成形すると同時に、前記予備フランジ部（５）を軸線方向へ押圧することにより予備フランジ部（５）の外周部を軸部（１４）の他端端部側へ突出させ、凹周状の連結コーナ（１０）を成形することを特徴とするスプライン鍛造品の成形方法。A shaft portion (14) extending in the axial direction, and a flange portion (15) having a larger diameter than the shaft portion (14) at one end of the shaft portion (14); A connecting corner (10) for connecting to the (14) is formed in the flange portion (15) in a concave circumferential shape along the shaft portion (14), and the other end of the shaft portion (14) from the connecting corner (10). In a method of forming a spline forged product in which a spline (9) is formed on the side of a spline (9), a spare shaft (4) having an outer diameter (d) smaller than a diameter (D) of a tooth root surface (9a) of the spline (9) in advance. ) And a preform (W1) having a spare flange portion (5) having a diameter larger than that of the spare shaft portion (4). Subsequently, the diameter of the spare shaft portion (4) is increased to form a spline (9). ) Is formed, and at the same time, the preliminary flange portion (5) is pressed in the axial direction so that the preliminary flange portion (5) is pressed. The outer peripheral portion is protruded to the other end portion side of the shaft portion (14) and method of molding spline forgings, which comprises forming a concave peripheral shape of the connecting corner (10) of). 前記スプライン（９）は、予備成形品（Ｗ１）の軸心付近を押圧して凹部（７）を成形することにより、鍛造肉を外周側へ流動させて成形することを特徴とする請求項１記載のスプライン鍛造品の成形方法。The said spline (9) presses the vicinity of the axis of a preform (W1) to form a concave portion (7), so that forged meat flows to the outer peripheral side and is formed. A method for forming a spline forged product as described in the above.
JP2002222707A 2002-07-31 2002-07-31 Forming method of spline forging product Pending JP2004058120A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009285716A (en) * 2008-05-30 2009-12-10 Musashi Seimitsu Ind Co Ltd Method for forging bevel gear
KR101122876B1 (en) * 2009-08-27 2012-03-20 고석재 Method for manufacturing spindle-housing by mechanical type press machine
CN113579138A (en) * 2021-06-11 2021-11-02 福建恒劲科技有限公司 Insulated Gate Bipolar Transistor (IGBT) electric heating spline warm extrusion forming complete equipment and forming process

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009285716A (en) * 2008-05-30 2009-12-10 Musashi Seimitsu Ind Co Ltd Method for forging bevel gear
US8341997B2 (en) 2008-05-30 2013-01-01 Musashi Seimitsu Industry Co., Ltd. Method of forging bevel gear
KR101122876B1 (en) * 2009-08-27 2012-03-20 고석재 Method for manufacturing spindle-housing by mechanical type press machine
CN113579138A (en) * 2021-06-11 2021-11-02 福建恒劲科技有限公司 Insulated Gate Bipolar Transistor (IGBT) electric heating spline warm extrusion forming complete equipment and forming process
CN113579138B (en) * 2021-06-11 2023-02-28 福建恒劲科技有限公司 Insulated Gate Bipolar Transistor (IGBT) electric heating spline warm extrusion forming complete equipment and forming process

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