JPH1058083A - Press formation of gear and die set for press formation - Google Patents
Press formation of gear and die set for press formationInfo
- Publication number
- JPH1058083A JPH1058083A JP21869996A JP21869996A JPH1058083A JP H1058083 A JPH1058083 A JP H1058083A JP 21869996 A JP21869996 A JP 21869996A JP 21869996 A JP21869996 A JP 21869996A JP H1058083 A JPH1058083 A JP H1058083A
- Authority
- JP
- Japan
- Prior art keywords
- gear
- tooth
- thickness
- mold
- dimension
- 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.)
- Granted
Links
Landscapes
- Forging (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する分野】本発明は歯車を圧造成形する方法
及びそれに用いるダイセットに関するものである。[0001] 1. Field of the Invention [0002] The present invention relates to a method of forging a gear and a die set used for the method.
【０００２】[0002]
【従来の技術及び発明が解決しようとする課題】出願人
は以前、型穴が段階的に完成歯車に近ずく様に順に大き
く形成された一組のダイに、最初に歯を形成する型穴か
ら順に各型穴に対応するパンチによってブランクを打込
み、該ブランクを段階的に完成歯車に近ずく様に成形す
る歯車製造方法を提案した(特公平６−２０５７２号)。
上記圧造による歯車の成形は、図４に示す如く、歯車の
基準ピッチ円Ｐ.Ｄ付近の歯の厚さＸよりも、歯元の歯
の厚さＹの方が小さい歯車については、基準ピッチ円付
近から歯元側にかけて材料が型穴に十分回り込まず、ヒ
ケが生じることが判った。BACKGROUND OF THE INVENTION Applicants have previously disclosed a mold cavity that initially forms teeth on a set of dies that are successively larger in size such that the mold cavity gradually approaches the finished gear. A method of manufacturing a gear was proposed in which a blank was punched in order from a punch corresponding to each mold hole, and the blank was formed stepwise so as to approach a finished gear (Japanese Patent Publication No. 6-20572).
As shown in FIG. 4, the gear forming by the above forging is performed by using a standard pitch for a gear whose tooth thickness Y at the root is smaller than the tooth thickness X near the reference pitch circle PD of the gear. It was found that the material did not sufficiently flow into the mold cavity from around the circle to the root side, causing sink marks.
【０００３】これは次の理由による。歯車圧造用ダイセ
ットの最初に歯を形成する型穴から最終製品に対応する
型穴までの型穴の拡がりの従来の考え方は、図６に最も
内側の鎖線で示す小さい型穴(130)から、２点鎖線で示
す次の型穴(140)、１点鎖線で示すその次の型穴(150)、
実線で示す最終製品に対応する型穴(160)まで、ほぼ相
似形に拡大させるものであった。This is based on the following reasons. The conventional concept of the extension of the mold cavity from the mold cavity forming the teeth at the beginning of the gear forging die set to the mold cavity corresponding to the final product is based on the small mold cavity (130) shown by the innermost chain line in FIG. The next mold hole (140) shown by the two-dot chain line, the next mold hole (150) shown by the one-dot chain line,
The mold was substantially similar in shape to the mold cavity (160) corresponding to the final product indicated by the solid line.
【０００４】即ち、最初に歯を形成する型穴(130)も、
歯元の厚み寸法Ｙ2よりも基準ピッチ円Ｐ.Ｄ近傍の歯の
厚みＸ2の方が大きい。すると、円柱形ブランクから最
初に歯を形成するとき、ブランクの肉は、最初に歯を形
成する型穴(130)の歯元の厚み寸法Ｙ2で半径方向に押出
されるため、図６に斜線で示す部分には肉が回り切らな
い。この肉が回り切らない部分が、最後まで影響して、
最終製品において、基準ピッチ円付近から歯元側にかけ
てヒケが生じ、歯面は正しいインボリュート曲線とはな
らず、例えばＪＩＳ等級で表される高精度な歯車の成形
を妨げる。本発明は、歯車圧造用ダイセットの型穴の拡
がりに工夫を施すことにより、上記問題を解決して高精
度ま歯車の圧造方法及びそれに使用するダイセットを明
らかにするものである。[0004] That is, the mold cavity (130) for forming the teeth first is also
Towards the thickness X 2 of the reference pitch circle P.D vicinity of the tooth than the dedendum of the thickness dimension Y 2 is large. Then, when forming the first teeth from the cylindrical blank, meat blank to be extruded radially tooth thickness dimension Y 2 of the mold cavity (130) initially form the teeth, Figure 6 The meat does not turn around in the shaded area. The part that this meat does not turn around influences to the end,
In the final product, sink marks occur from the vicinity of the reference pitch circle to the root side, and the tooth surface does not have a correct involute curve, which hinders the formation of a high-precision gear represented by, for example, JIS grade. The present invention solves the above-mentioned problems by devising the expansion of the mold hole of the die set for gear forging, and clarifies a method for forging a high-accuracy gear and a die set used for the method.
【０００５】[0005]
【課題を解決する手段】本発明の歯車製造方法は、型穴
が段階的に完成歯車に近ずく様に順に大きく形成された
一組のダイ(13)(14)(15)(16)に、最初に歯を形成する型
穴(13a)から順に各型穴に対応するパンチ(31)(32)(33)
(34)によってブランクを打込み、該ブランクを段階的に
完成歯車に近ずく様に成形する方法において、最初に歯
を形成する型穴(13a)は歯車の歯元の厚みに対応する寸
法Ｙ1と基準ピッチ円近傍の厚みに対応する寸法Ｘ1が同
じ或いは前者の寸法Ｙ1が後者の寸法Ｘ1よりも大であ
り、最初に歯を形成する型穴(13a)から最終製品に対応
する型穴(15a)への型穴の徐々なる拡がりは、歯車の歯
元の厚みに対応する寸法の拡大値よりも基準ピッチ円近
傍の厚みに対応する寸法の拡大値の方が大きい一組のダ
イ(13)(14)(15)(16)を用いて圧造し、基準ピッチ円近傍
の歯の厚さＸよりも歯元の歯の厚さＹの方が小さい歯車
を成形する。The method of manufacturing a gear according to the present invention is directed to a set of dies (13), (14), (15), and (16) in which a mold hole is gradually formed so as to gradually approach a completed gear. The punches (31), (32), and (33) corresponding to each mold hole in order from the mold hole (13a) that first forms teeth.
In the method of driving a blank according to (34) and forming the blank stepwise so as to approach the finished gear, the mold hole (13a) for forming teeth first has a dimension Y 1 corresponding to the thickness of the tooth root of the gear. dimension X 1 are the same or former dimension Y 1 corresponding to the thickness of the vicinity of the reference pitch circle is larger than the latter dimension X 1, corresponding to the final product from the mold cavity (13a) initially forming the teeth and The gradual expansion of the mold hole into the mold hole (15a) is due to the fact that the enlarged value of the dimension corresponding to the thickness near the reference pitch circle is larger than the enlarged value of the dimension corresponding to the tooth root thickness of the gear. A gear is formed using the dies (13), (14), (15), and (16) to form a gear having a tooth thickness Y at the base of the tooth smaller than a tooth thickness X near the reference pitch circle.
【０００６】本発明のダイセットは、型穴が段階的に完
成歯車に近ずく様に順に大きく形成された一組のダイ(1
3)(14)(15)(16)において、最初に歯を形成する型穴(13
a)は歯車の歯元の厚みに対応する寸法Ｙ1と基準ピッチ
円近傍の厚みに対応する寸法Ｘ1が同じ或いは前者の寸
法Ｙ1が後者の寸法Ｘ1よりも大であり、最初に歯を形成
する型穴(13a)から最終製品に対応する型穴(15a)への型
穴の徐々なる拡がりは、歯車の歯元の厚みに対応する寸
法の拡大値よりも基準ピッチ円近傍の厚みに対応する寸
法の拡大値の方が大きい。[0006] The die set of the present invention comprises a set of dies (1) in which the mold holes are formed in order to gradually approach the completed gear.
3) In (14), (15), and (16), first, mold holes (13
a) is greater than the dimension Y 1 and a reference pitch circle size X 1 of the dimension X 1 corresponding to the thickness of the same or former dimension Y 1 is the latter near corresponding to tooth thickness of the gear, the first The gradual expansion of the mold hole from the mold hole (13a) forming the teeth to the mold hole (15a) corresponding to the final product is closer to the reference pitch circle than the enlargement value of the dimension corresponding to the gear root thickness. The enlargement value of the dimension corresponding to the thickness is larger.
【０００７】[0007]
【作用及び効果】最初に歯を形成する型穴(13a)は歯車
の歯元の厚みに対応する寸法Ｙ1と基準ピッチ円近傍の
厚みに対応する寸法Ｘ1が同じ或いは前者の寸法Ｙ1が後
者の寸法Ｘ1よりも大であるから、該型穴(13a)の隅々ま
で肉が充満し、従来の様にこの段階で型穴と材料との間
に隙間が生じることはない。従って、次の工程からは、
型穴の徐々なる拡がりが、歯車の歯元の厚みに対応する
寸法の拡大値よりも基準ピッチ円近傍の厚みに対応する
寸法の拡大値の方が大きなダイによって段階的に歯を拡
大するため、歯面にヒケの生じていない正しいインボリ
ュート曲線の高精度の歯車を能率的に製造できる。ブラ
ンクを段階的に圧造して、徐々に完成歯車に近ずけるか
ら、各型穴での加工度は小さく、金型への負荷は軽減さ
れ、ダイの寿命は延長する。[Action and Effect] The first mold cavity (13a) to form the teeth dimensions Y 1 and the reference pitch circle near dimensions X 1 corresponding to the thickness of the same or of the former dimension Y 1 corresponding to the tooth thickness of the gear There because it is larger than the latter dimension X 1, meat filled throughout the mold hole (13a), there is no generation of a gap between the conventional mold cavity and the material at this stage as the. Therefore, from the next step,
The gradual expansion of the mold hole is due to the stepwise enlargement of teeth by a die where the enlargement value of the dimension corresponding to the thickness near the reference pitch circle is larger than the enlargement value of the dimension corresponding to the tooth root thickness of the gear. In addition, it is possible to efficiently manufacture a high-precision gear having a correct involute curve with no sink mark on the tooth surface. Since the blank is gradually pressed and gradually approached to the finished gear, the degree of processing in each mold hole is small, the load on the mold is reduced, and the life of the die is extended.
【０００８】[0008]
【発明の実施の態様】図３は、本発明の方法によって製
造した完成歯車(５)を示しており、完成歯車(５)の両側
面の中央部に円形の凸段部(54)(54)、その外側に段差0.
5mmの環状の凹段部(53)(53)が形成されおり、凸段部(5
4)の径は歯底径よりも小さい。歯部には突出高さが歯車
側面の段差よりも小さいバリ(58)が生じている。図４
は、完成歯車の歯部を示しており、基準ピッチ円近傍の
歯の厚さＸよりも歯元の歯の厚さＹの方が小さい。歯面
はインボリュート曲線である。図１は、トランスファー
プレスの材料切断ステーションＳ1、予備成形ステーシ
ョンＳ2、最初の歯形成圧造ステーションＳ3及び各ステ
ーションによって加工されたブランクＢ１〜Ｂ３を示し
ている。図２は、次の３つの圧造ステーションＳ４、Ｓ
５、Ｓ６及び各ステーションによって加工されたブラン
クＢ４、Ｂ５、完成歯車(５)を示している。尚、予備成
形及び各圧造ステーションに対応して配備した突出しピ
ン(２)(21)(22)(23)及び孔抜きパンチ(24)は、待機定位
置よりも後方にずらせて図示している。FIG. 3 shows a finished gear (5) manufactured by the method of the present invention. The finished gear (5) has circular convex steps (54) (54) at the center of both sides. ), A step 0 on the outside.
5 mm annular concave steps (53) and (53) are formed, and the convex steps (5
The diameter of 4) is smaller than the root diameter. A burr (58) whose protruding height is smaller than the step on the side surface of the gear is generated in the tooth portion. FIG.
Indicates a tooth portion of the completed gear, and the tooth thickness Y of the tooth root is smaller than the tooth thickness X near the reference pitch circle. The tooth surface is an involute curve. Figure 1 is a material cutting station S 1 of the transfer press, preforming station S 2, shows a blank B1~B3 processed by the first tooth formed forging station S 3, and each station. FIG. 2 shows the following three forging stations S4, S
5, blanks B4 and B5 processed by each station and each station, and a completed gear (5) are shown. Note that the protruding pins (2), (21), (22), (23) and the hole punch (24) provided corresponding to the preforming and forging stations are shown shifted rearward from the standby fixed position. .
【０００９】トランスファープレスのダイブロック(１)
には切断クイル(11)、予備成形ダイ(12)、第１圧造ダイ
(13)、第２圧造ダイ(14)、第３圧造ダイ(15)、第４圧造
ダイ(16)が配備されている。ダイブロック(１)に対向し
てラム(４)が往復動可能に配備され、該ラムには上記各
ダイに対向して圧造パンチ(３)(31)(32)(33)(34)が取り
付けられている。切断クイル(11)の貫通孔(11a)を通っ
て圧造側に送り込まれた線材(６)は、該クイルの軸芯と
直交して往復する切断ナイフ(図示せず)によって剪断さ
れると共に、該切断ナイフによって予備成形ステーショ
ンＳ2に移送される。ダイブロック(１)上には、予備成
形ステーションＳ2、第１、第２、第３圧造ステーショ
ンＳ3、Ｓ4、Ｓ5にて形成された各ブランクＢ２、Ｂ
３、Ｂ４、Ｂ５を次のステーションに移行させるトラン
スファー装置(図示せず)が配備されている。Die block for transfer press (1)
Has a cutting quill (11), a preforming die (12), a first forging die
(13), a second forging die (14), a third forging die (15), and a fourth forging die (16) are provided. A ram (4) is provided so as to be able to reciprocate opposite to the die block (1), and the forging punches (3), (31), (32), (33), and (34) are provided on the ram so as to face the dies. Installed. The wire rod (6) sent to the forging side through the through hole (11a) of the cutting quill (11) is sheared by a cutting knife (not shown) that reciprocates orthogonally to the axis of the quill, is transferred to a pre-forming station S 2 by the cutting knife. On the die block (1) is preformed station S 2, the first, second, third forging station S 3, S 4, each formed by S 5 blank B2, B
A transfer device (not shown) for transferring 3, B4, B5 to the next station is provided.
【００１０】予備成形ダイ(12)の型穴(12a)は断面円形
であって、底部外周は軸芯に対して３０゜傾斜した斜面
(12b)に形成され、斜面と軸心に平行に壁面との境界は
丸く面取りが施されている。予備成形ダイ(12)の底中央
に突出しピン挿通孔(12c)が開設され、突出しピン(２)
が摺動可能に嵌まっている。突出しピン(２)の先端は平
坦面(2a)に形成されている。予備成形ダイ(12)の開口縁
はブランクに対する案内面となるテーパ面(12d)が形成
されている。第１、第２、第３、第４圧造ダイ(13)(14)
(15)(16)の型穴(13a)(14a)(15a)(16a)は夫々歯車の溝形
状に対応して等間隔に突条(13b)(14b)(15b)(16b)が突設
されている。各型穴は第１圧造ダイ(13)から第４圧造ダ
イ(16)に順に僅か大きくなっており、最終段の第４圧造
ダイ(16)の型穴(16a)の断面形状は完成歯車(５)の外周
形状に対応している。The die hole (12a) of the preforming die (12) is circular in cross section, and the outer periphery at the bottom is inclined by 30 ° with respect to the axis.
It is formed in (12b), and the boundary between the inclined surface and the wall surface is rounded and chamfered. A protruding pin insertion hole (12c) is opened at the bottom center of the preforming die (12), and the protruding pin (2)
Are slidably fitted. The tip of the protruding pin (2) is formed on a flat surface (2a). The opening edge of the preforming die (12) has a tapered surface (12d) serving as a guide surface for the blank. First, second, third and fourth forging die (13) (14)
The projections (13b), (14b), (15b), and (16b) of the mold holes (13a), (14a), (15a), and (16a) of (15) and (16) protrude at regular intervals corresponding to the groove shape of the gear. Has been established. Each die hole is slightly larger in order from the first die for die (13) to the fourth die for die (16), and the cross-sectional shape of the die hole (16a) of the fourth die for die (16) in the final stage is a finished gear ( It corresponds to the outer peripheral shape of 5).
【００１１】本発明の特徴は、最初に歯を形成する型穴
(13a)は歯車の歯元の厚みに対応する寸法と基準ピッチ
円近傍の厚みに対応する寸法が同じ或いは前者の寸法Ｙ
1が後者の寸法Ｘ1よりも大であり、最初に歯を形成する
型穴(31)から最終製品に対応する型穴(15a)への型穴の
徐々なる拡がりは、歯車の歯元の厚みに対応する寸法の
拡大値よりも基準ピッチ円近傍の厚みに対応する寸法の
拡大値の方が大きくなっている。これを図５で示せば、
最も内側の鎖線で示すのが、第１圧造ダイ(13)の歯部の
型穴(13a)、次の２点鎖線で示すのが第２圧造ダイ(14)
の歯部の型穴(14a)、その次の１点鎖線で示すのが第３
圧造ダイ(15)の歯部の型穴(15a)、一番外側の実線で示
すのが第４圧造ダイ(16)の歯部の型穴(16a)である。A feature of the present invention is that a mold cavity for initially forming teeth is provided.
(13a) is the same as the dimension corresponding to the tooth root thickness and the dimension corresponding to the thickness near the reference pitch circle, or the former dimension Y
1 is larger than the latter dimension X 1, initially the gradual spread of the mold cavity of the tooth from the mold cavities (31) forming a the mold cavity (15a) corresponding to the final product, the tooth root of the gear The enlargement value of the dimension corresponding to the thickness near the reference pitch circle is larger than the enlargement value of the dimension corresponding to the thickness. This is shown in FIG.
The innermost chain line indicates the mold cavity (13a) of the tooth portion of the first forging die (13), and the next two-dot chain line indicates the second forging die (14).
The mold hole (14a) of the tooth part of the third
The mold hole (15a) in the tooth portion of the forging die (15), and the outermost solid line is the mold hole (16a) in the tooth portion of the fourth forging die (16).
【００１２】第１、第２、第３圧造ダイ(13)(14)(15)の
型穴(13a)(14a)(15a)の深さは完成歯車(５)の厚みより
も大であって、第１、第２圧造ダイ(13)(14)の型穴の底
面は軸心に対して直交している。第３圧造ダイ(15)の型
穴の底面は外周部が環状に0.5mm程度高く***した環状
***部(15c)を形成している。環状***部(15c)の内径
は、歯車の歯底径よりも小さい。型穴(13a)(14a)(15a)
の中央には突出しピン挿入孔(13c)(14c)(15c)が開設さ
れ、該孔に突出しピン(21)(22)(23)が摺動可能に配備さ
れる。第１、第２圧造ダイ(13)(14)の突出しピン(21)(2
2)の突出し側先端は軸心に直交する平坦面(21a)(22a)に
形成され、第３圧造ダイ(15)の突出しピン(23)の突出し
側先端はブランクＢ４に打込む打込み凸部(23a)が形成
されている。第４圧造ダイ(16)は孔抜きダイを兼用して
おり、ダイの奥には突出しスリーブ(25)が摺動可能に嵌
まり、該スリーブの軸心に孔抜きパンチ(24)がスリーブ
に対して摺動可能に配備されている。各型孔(13a)(14a)
(15a)(16a)のラム側開口縁にはブランクＢ３、Ｂ４、Ｂ
５を型穴に確実に案内するガイド斜面(13d)(14d)(15d)
(16d)が形成されている。The depth of the mold holes (13a) (14a) (15a) of the first, second and third forging dies (13) (14) (15) is larger than the thickness of the completed gear (5). The bottom surfaces of the mold holes of the first and second forging dies (13, 14) are orthogonal to the axis. The bottom surface of the die hole of the third forging die (15) forms an annular ridge (15c) whose outer peripheral portion is annularly raised by about 0.5 mm. The inner diameter of the annular ridge (15c) is smaller than the gear root diameter. Mold hole (13a) (14a) (15a)
Projecting pin insertion holes (13c), (14c), (15c) are opened in the center of the, and the projecting pins (21), (22), (23) are slidably provided in the holes. The protruding pins (21) (2) of the first and second forging dies (13) (14)
The protruding end of 2) is formed on a flat surface (21a) (22a) orthogonal to the axis, and the protruding end of the protruding pin (23) of the third forging die (15) is a driving protrusion for driving into the blank B4. (23a) is formed. The fourth forging die (16) also serves as a punching die, and a protruding sleeve (25) is slidably fitted in the back of the die, and a punching punch (24) is fitted on the sleeve at the axis of the sleeve. It is provided so as to be slidable. Each mold hole (13a) (14a)
(15a) Blanks B3, B4, B
Guide slope (13d) (14d) (15d) to guide 5 securely into the mold hole
(16d) is formed.
【００１３】前記予備成形ダイ(12)に対応する予備圧造
パンチ(３)は先端に軸心に直交する面に対して約３゜の
角度の円錐面(3a)を***形成している。第１、第２、第
３、第４圧造ダイ(13)(14)(15)(16)に対向配備された、
第１、第２、第３、第４圧造パンチ(31)(32)(33)(34)
は、共にダイの孔形状に対応して外周に歯面(31a)(32a)
(33a)(34a)を形成している。又、第１、第２、第３圧造
パンチ(31)(32)(33)の先端中央にはブランクＢ２、Ｂ
３、Ｂ４の端面に凹部(54)(55)(56)を形成するための突
部(31b)(32b)(33b)が形成されている。更に、第２、第
３、第４圧造パンチ(31)(32)(33)の先端外周部は、環状
の***部(32c)(33c)(34c)が形成されている。該***部
(32c)(33c)(34c)の***高さは0.5mmであり、内径は前記
第３圧造ダイ(15)の型穴(15a)の底面の環状***部(15c)
の内径に一致している。第４圧造パンチ(34)には、ブラ
ンクＢ５を孔抜きした際の孔抜きカスを排出するための
貫通孔(34b)が開設されている。The pre-forming punch 3 corresponding to the pre-forming die 12 has a protruding conical surface 3a at an end thereof at an angle of about 3 ° with respect to a plane perpendicular to the axis. The first, second, third, and fourth forging dies (13), (14), (15), and (16) are provided to face each other.
First, second, third, fourth forging punches (31) (32) (33) (34)
Are tooth surfaces (31a) and (32a) on the outer circumference, both corresponding to the hole shape of the die.
(33a) and (34a) are formed. Blanks B2 and B are provided at the center of the leading ends of the first, second and third forging punches (31), (32) and (33).
3. Projections (31b) (32b) (33b) for forming the recesses (54) (55) (56) are formed on the end faces of B4. Furthermore, annular raised portions (32c) (33c) (34c) are formed on the outer peripheral portions of the distal ends of the second, third, and fourth pressed punches (31), (32), (33). The ridge
(32c) (33c) (34c) has a raised height of 0.5 mm, the inner diameter of the annular ridge (15c) on the bottom surface of the mold hole (15a) of the third forging die (15)
The inside diameter of A through-hole (34b) is formed in the fourth forging punch (34) for discharging a punching waste when the blank B5 is punched.
【００１４】然して、切断ステーションＳ1から予備成
形ステーションＳ2に移送されたブランクＢ2は、該ステ
ーションＳ2にて、ダイ(12)の底形状及びパンチの先端形
状に対応してダイ側先端外周部が30°のテーパ面(53)に
形成され、他端面は外周から中心へ緩やかに凹んでい
る。予備ステーションＳ2から第１圧造ステーションＳ3
に移送されたブランクＢ３は、該ステーションＳ3の型
穴に対応して略歯車形状に成形され、パンチ側端面にパ
ンチ(32)の先端に対応して凹み(55)が形成される。第１
圧造ステーションＳ3の型穴(13a)は歯車の歯元の厚みに
対応する寸法と基準ピッチ円近傍の厚みに対応する寸法
が同じ或いは前者の寸法Ｙ1が後者の寸法Ｘ1よりも大で
あるから、該型穴(13a)の歯面に対応する隅々まで肉が
充満し、従来の様にこの段階で型穴の歯面に対応する部
分と材料との間に隙間が生じることはない。型穴(13a)
の最小内径は、予備成形されたブランクＢ２の径よりも
少し大きいため、ブランクＢ２を型穴(13a)にスムーズ
に打込み出来る。However, the blank B 2 transferred from the cutting station S 1 to the preforming station S 2 receives the blank at the die side at the station S 2 corresponding to the bottom shape of the die (12) and the tip shape of the punch. The outer peripheral portion is formed as a 30 ° tapered surface (53), and the other end surface is gently concave from the outer periphery to the center. Preliminary station S 2 first forging station S 3
Blank B3, which is transported to is molded in a substantially gear shape corresponding to the mold cavity of the station S 3, depressions corresponding to the tip of the punch (32) to the punch end face (55) is formed. First
Mold cavity forging station S 3 (13a) is larger than the dimension X 1 dimension and the reference pitch circle dimension Y 1 dimension corresponding to the thickness of the same or former neighborhood corresponding to the tooth root of the thickness of the latter gears Therefore, the meat is filled to every corner corresponding to the tooth surface of the mold hole (13a), and a gap is formed between the material corresponding to the tooth surface of the mold hole and the material at this stage as in the related art. Absent. Mold hole (13a)
Is slightly larger than the diameter of the preformed blank B2, so that the blank B2 can be smoothly driven into the mold hole (13a).
【００１５】上記第１圧造工程に於て、ブランクＢ３の
材料肉は、型穴の歯面に対応する部分には隙間なく充満
するが、型穴(14a)の溝奥まで完全には流れ込まず、従
ってブランクＢ３の歯形の先端は、勿論完全なる歯型で
はない。第１圧造ステーションＳ3から第２圧造ステー
ションＳ4に移送されたブランクＢ４は、該ステーショ
ンＳ4の型穴(14a)に対応して略歯車形状に形成され、パ
ンチ(33)側の端面の凹み(55)はパンチ(32)の先端形状に
対応して深くなる。又、パンチ(32)の先端外周の***部
(32c)によって、ブランクＢ４のパンチ側面の外周部に
は環状の凹段部(53)が形成される。第２圧造ステーショ
ンＳ4から反転して第３圧造ステーションＳ5に移送され
たブランクＢ5は、パンチ(33)による該ステーションＳ5
の型穴(15a)への打込みにより該型穴(15a)に対応して略
歯車形状に形成される。又、パンチ(33)の先端外周の隆
起部(33c)によって、ブランクＢ５のパンチ側面の外周
には環状の凹段部(53)が形成される。In the first forging step, the material of the blank B3 fills the portion corresponding to the tooth surface of the mold hole without a gap, but does not completely flow into the groove of the mold hole (14a). Therefore, the tip of the tooth profile of the blank B3 is, of course, not a perfect tooth profile. Blank B4, which is transferred from the first forging station S 3 to the second forging station S 4 is formed in a substantially gear shape corresponding to the mold cavity of the station S 4 (14a), a punch (33) end surface of the side of the The recess (55) becomes deeper corresponding to the tip shape of the punch (32). Also, a raised portion on the outer periphery of the tip of the punch (32)
By (32c), an annular concave step (53) is formed on the outer peripheral portion of the punch B side surface of the blank B4. The blank B 5 , which has been inverted from the second forging station S 4 and transferred to the third forging station S 5 , is transferred to the station S 5 by the punch (33).
By being driven into the mold hole (15a), a substantially gear shape is formed corresponding to the mold hole (15a). Further, an annular concave step (53) is formed on the outer periphery of the punch side surface of the blank B5 by the raised portion (33c) on the outer periphery of the tip of the punch (33).
【００１６】第３圧造ステーションＳ5の型穴は、第２
圧造ステーションＳ4の型穴(14a)よりも少し大きく、
又、ブランクＢ５の中央部が凹むから、それに対応して
第３圧造ステーションＳ5で圧造されたブランクＢ５の
外形は、第２圧造ステーションＳ4で圧造したブランク
Ｂ４よりも大きくなる。第３圧造ステーションＳ5から
第４圧造ステーションＳ6に移送されたブランクＢ５は
型穴内で孔抜きパンチ(24)によって孔抜きが行なわれ、
このときブランクの材料肉は、パンチ側への移動は妨げ
られているから外周方向に強く押し出され、型穴(16a)
の溝の隅々にまで充満し、完成歯車に対応する形状に圧
造され、スリーブ(25)に打ち出されて完成歯車(５)が排
出される。図７に示す如く、圧造成形した歯車(５)の側
面にはバリ(58)が成形されることは避けられず、歯車の
組込時にバリが邪魔になって取付け誤差を生じる。この
ためバリ取り加工が必要であり、手間とコストがかかっ
たが、実施例の完成歯車(５)の様に両端面の中央部にバ
リの突出高さより大きな段差の凸段部(54)を形成すれ
ば、バリ取り加工は不要となる。The mold cavity of the third forging station S 5 is
Slightly larger than the mold cavity of the forging station S 4 (14a),
Further, since the central portion of the blank B5 is recessed, the outer shape of the heading blanks B5 in the third forging station S 5 correspondingly larger than the blank B4 was heading in the second forging station S 4. Blank B5 transferred from the third forging station S 5 to the fourth forging station S 6 is piercing by punching a punch (24) is carried out in the mold cavity,
At this time, the blank material is strongly pushed out in the outer peripheral direction because movement to the punch side is hindered, and the mold hole (16a)
The groove is filled up to every corner, is forged into a shape corresponding to the completed gear, is punched out into the sleeve (25), and the completed gear (5) is discharged. As shown in FIG. 7, it is inevitable that burrs (58) are formed on the side surfaces of the forged gears (5). For this reason, deburring was necessary, which was troublesome and costly. However, as in the case of the completed gear (5) of the embodiment, a projecting step (54) having a step larger than the projection height of the burr was provided at the center of both end faces. Once formed, deburring is not required.
【００１７】上記の如く、本発明では、最初に歯を形成
する型穴(13a)は歯車の歯元の厚みに対応する寸法と基
準ピッチ円近傍の厚みに対応する寸法が同じ或いは前者
の寸法Ｙ1が後者の寸法Ｘ1よりも大であるから、該型穴
(13a)の歯面に対応する隅々まで肉が充満し、従来の様
にこの段階で型穴の歯面に対応する部分と材料との間に
隙間が生じることはない。従って、次の工程からは、型
穴の徐々なる拡がりが、歯車の歯元の厚みに対応する寸
法の拡大値よりも基準ピッチ円近傍の厚みに対応する寸
法の拡大値の方が大きなダイによって段階的に歯を拡大
するため、歯部にヒケの生じていない高精度の歯車を能
率的に製造できる。尚、孔抜きパンチ(24)は、型孔(16
a)内で定位置に固定保持しておき、ブランクＢ５を圧造
パンチ(34)によって型孔(16a)に打込む際に、孔抜きを
行なうことも、或はブランクＢ５を圧造パンチ(34)によ
って型孔(16a)打込んだ後、孔抜きパンチ(24)をブラン
クＢ５に打込んで孔抜きすることも可能である。実施例
では、歯先径20.10mm、歯底径15.40mm、厚み10.0mm、孔
径8.50、歯数18の歯車を６０個/分の割で生産した。As described above, in the present invention, the mold hole (13a) for forming teeth first has the same size as the thickness corresponding to the tooth root thickness of the gear and the size corresponding to the thickness near the reference pitch circle, or the former size. Since Y 1 is larger than the latter dimension X 1 ,
The meat is filled up to every corner corresponding to the tooth surface of (13a), and there is no gap between the material corresponding to the tooth surface of the mold cavity and the material at this stage as in the conventional case. Therefore, from the next step, the gradual expansion of the die hole is caused by the die in which the expansion value of the dimension corresponding to the thickness near the reference pitch circle is larger than the expansion value of the dimension corresponding to the tooth root thickness of the gear. Since the teeth are enlarged stepwise, a high-precision gear with no sink marks on the teeth can be efficiently manufactured. The hole punch (24) is
The blank B5 is fixed and held in a fixed position in a), and when punching the blank B5 into the mold hole (16a) by the forging punch (34), punching may be performed, or the blank B5 may be punched (34). After punching the mold hole (16a), it is possible to punch a hole by punching a punch (24) into the blank B5. In the embodiment, gears having a tooth tip diameter of 20.10 mm, a tooth bottom diameter of 15.40 mm, a thickness of 10.0 mm, a hole diameter of 8.50 and a number of teeth of 18 were produced at a rate of 60 teeth / minute.
【００１８】上記の如く、本発明ではブランクが徐々に
完成歯車に近ずく様に段階的に圧造するから、各型穴で
の加工度は小さく、金型への負担は軽減され、金型の寿
命は延長する。トランスファープレスによる圧造である
から、生産能率が向上する。又、ブランクを徐々に完成
歯車の形状に近ずけ、最終段の型穴にブランクを打込ん
だ状態で孔抜きする際にもブランクの肉を半径方向に押
出し、型穴の溝奥の隅々に材料肉を行き渡らせて精度の
高い歯車を形成できる。尚、本発明の実施に際し、予備
成形工程を除く圧造工程を３段階の工程で行なうことも
勿論可能である等、特許請求の範囲に記載の範囲で種々
の変形が可能である。As described above, in the present invention, since the blank is formed in a stepwise manner so that the blank gradually approaches the completed gear, the degree of working in each mold hole is small, the burden on the mold is reduced, and the mold is reduced. Life is extended. Since the forging is performed by transfer press, production efficiency is improved. Also, when the blank is gradually approached to the shape of the finished gear and the blank is punched in the final stage mold hole, the blank is extruded in the radial direction when punching the hole, A highly accurate gear can be formed by distributing the material in each case. In carrying out the present invention, various modifications are possible within the scope of the claims, for example, it is possible to perform the forging process except for the preforming process in three stages.
【図１】第１工程から第３工程までの説明図である。FIG. 1 is an explanatory view from a first step to a third step.
【図２】第４工程から第６工程までの説明図である。FIG. 2 is an explanatory view from a fourth step to a sixth step.
【図３】歯車の断面図である。FIG. 3 is a sectional view of a gear.
【図４】歯車の正面図である。FIG. 4 is a front view of a gear.
【図５】工程別の型穴の変化の説明図である。FIG. 5 is an explanatory diagram of a change in a mold cavity for each process.
【図６】従来例における工程別の型穴の変化の説明図で
ある。FIG. 6 is an explanatory diagram of a change in a mold cavity for each process in a conventional example.
【図７】従来の圧造成形歯車の断面図である。FIG. 7 is a sectional view of a conventional forged gear.
(12) ダイ (13) ダイ (14) ダイ (15) ダイ (16) ダイ (12a) 型穴 (13b) 型穴 (14c) 型穴 (15d) 型穴 (16e) 型穴 (12) Die (13) Die (14) Die (15) Die (16) Die (12a) Die hole (13b) Die hole (14c) Die hole (15d) Die hole (16e) Die hole
Claims (2)
に大きく形成された一組のダイ(13)(14)(15)(16)に、最
初に歯を形成する型穴(13a)から順に各型穴に対応する
パンチ(31)(32)(33)(34)によってブランクを打込み、該
ブランクを段階的に完成歯車に近ずく様に成形する方法
において、最初に歯を形成する型穴(13a)は歯車の歯元
の厚みに対応する寸法Ｙ1と基準ピッチ円近傍の厚みに
対応する寸法Ｘ1が同じ或いは前者の寸法Ｙ1が後者の寸
法Ｘ1よりも大であり、最初に歯を形成する型穴(13a)か
ら最終製品に対応する型穴(15a)への型穴の徐々なる拡
がりは、歯車の歯元の厚みに対応する寸法の拡大値より
も基準ピッチ円近傍の厚みに対応する寸法の拡大値の方
が大きい一組のダイ(13)(14)(15)(16)を用いて圧造し、
基準ピッチ円近傍の歯の厚さＸよりも歯元の歯の厚さＹ
の方が小さい歯車を成形する方法。1. A pair of dies (13), (14), (15) and (16), each of which has a die hole formed in order so as to gradually approach a completed gear, is provided with a die hole for forming teeth first. In the method of punching blanks by punches (31) (32) (33) (34) corresponding to each mold hole in order from 13a), and forming the blank stepwise so as to approach the completed gear, teeth are first formed. formed to mold cavity (13a) is larger than the dimension Y 1 and a reference pitch circle size X 1 of the dimension X 1 corresponding to the thickness of the same or former dimension Y 1 is the latter near corresponding to tooth thickness of the gear The gradual expansion of the mold hole from the mold hole (13a) forming the teeth first to the mold hole (15a) corresponding to the final product is larger than the enlargement value of the dimension corresponding to the tooth root thickness of the gear. Forging using a set of dies (13) (14) (15) (16) with a larger expansion value of the dimension corresponding to the thickness near the reference pitch circle,
Thickness of the tooth at the root of the tooth Y than the thickness X of the tooth near the reference pitch circle
Is a method of forming a smaller gear.
に大きく形成された一組のダイ(13)(14)(15)(16)におい
て、最初に歯を形成する型穴(13a)は歯車の歯元の厚み
に対応する寸法Ｙ1と基準ピッチ円近傍の厚みに対応す
る寸法Ｘ1が同じ或いは前者の寸法Ｙ1が後者の寸法Ｘ1
よりも大であり、最初に歯を形成する型穴(13a)から最
終製品に対応する型穴(15a)への型穴の徐々なる拡がり
は、歯車の歯元の厚みに対応する寸法の拡大値よりも基
準ピッチ円近傍の厚みに対応する寸法の拡大値の方が大
きいことを特徴とする圧造用ダイセット。2. A set of dies (13), (14), (15) and (16) in which the mold holes are formed in order to gradually approach the completed gear, and the mold holes which form teeth first (2). 13a) the dimension Y 1 and a reference pitch circle size dimensions X 1 corresponding to the thickness of the same or of the former in the vicinity of Y 1 is the latter dimension X 1 that corresponds to the tooth thickness of the gear
The gradual expansion of the mold cavity from the mold cavity (13a) that initially forms the teeth to the mold cavity (15a) corresponding to the final product increases the dimensions corresponding to the gear tooth thickness. A die set for forging, characterized in that the enlargement value of the dimension corresponding to the thickness near the reference pitch circle is larger than the value.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21869996A JP2825793B2 (en) | 1996-08-20 | 1996-08-20 | Gear forging forming method and forging die set |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21869996A JP2825793B2 (en) | 1996-08-20 | 1996-08-20 | Gear forging forming method and forging die set |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH1058083A true JPH1058083A (en) | 1998-03-03 |
| JP2825793B2 JP2825793B2 (en) | 1998-11-18 |
Family
ID=16724038
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21869996A Expired - Fee Related JP2825793B2 (en) | 1996-08-20 | 1996-08-20 | Gear forging forming method and forging die set |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2825793B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005161340A (en) * | 2003-12-01 | 2005-06-23 | Kondoo Seikoo Kk | Method for producing helical gear |
| CN103658499A (en) * | 2013-12-10 | 2014-03-26 | 常熟柏科汽车零件再制造有限公司 | Starter gear face tooth cold forging technology |
-
1996
- 1996-08-20 JP JP21869996A patent/JP2825793B2/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005161340A (en) * | 2003-12-01 | 2005-06-23 | Kondoo Seikoo Kk | Method for producing helical gear |
| CN103658499A (en) * | 2013-12-10 | 2014-03-26 | 常熟柏科汽车零件再制造有限公司 | Starter gear face tooth cold forging technology |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2825793B2 (en) | 1998-11-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5894752A (en) | Method and system for warm or hot high-velocity die forging | |
| JP2002213476A (en) | Method of manufacturing tripod constant velocity universal joint outer race | |
| JP2825793B2 (en) | Gear forging forming method and forging die set | |
| EP1038609A1 (en) | Method of manufacturing latch plate | |
| JP2851591B2 (en) | Forging tool set for gear manufacturing | |
| JP2825798B2 (en) | Gear forging / forging method and die set | |
| EP0277269B1 (en) | Process for manufacturing a part having a tooth profile and boss | |
| JP3637249B2 (en) | Manufacturing method of spherical ring on outer diameter side | |
| JP4856889B2 (en) | Cold forging method | |
| JPH11300447A (en) | Manufacture of gear | |
| JP2844275B2 (en) | Method of forming inner ring of constant velocity joint | |
| KR100573379B1 (en) | Forming method of double gear | |
| CN112916789B (en) | Clean forming process method of internal tooth profile | |
| JPH0620573B2 (en) | Gear press forming die | |
| JP3237146B2 (en) | Method of manufacturing forged material, method of forging and method of manufacturing forged material | |
| JP4907811B2 (en) | Chamfering method for clutch gear | |
| JPS58122133A (en) | Method and device for processing punching hole | |
| JP2005118848A (en) | Forging apparatus and forging method | |
| JPH0120042Y2 (en) | ||
| JP2001246441A (en) | Manufacturing method of spline piece gear | |
| CN114833234A (en) | Forming process of stepped non-through tooth-shaped part | |
| JP3517771B2 (en) | Manufacturing method of nut with washer | |
| JP2791625B2 (en) | Manufacturing method of toothed molded products | |
| JPH0780590A (en) | Manufacture of bevel gear | |
| JP2002192296A (en) | Cold forging method of bottomed spline hole and cold forged parts |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 19980804 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| LAPS | Cancellation because of no payment of annual fees |