JPS5997731A - Form rolling method of gear - Google Patents

Abstract

PURPOSE:To improve remarkably the accuracy of a tooth profile and tooth trace in the stage of pressing rolling tools to a blank material and generating a gear by reversing intermittently the relative rotating direction applied on the blank material to level off the twist parts formed on both sides in a unit tooth part. CONSTITUTION:A blank material for a gear is freely rotatably supported between rolling tools positioned oppositely to each other, and the tools are driven to rotate so that the tooth profile is generated on the blank material while the material is pressed by the tools. An under fill 1ta is produced by the metallic flow heading toward the center in the tooth part on the driven side of the tooth ta of a blank material G2 and a twist part 2ta is produced by the metallic flow heading toward the tip and deddendum on the follower side in the stage (a) when the tools are rotated as required. The force acting on the tooth tb is reversed and the twist at the projecting part 2tb is suppressed on the driven side and a twist part 1tb is produced on the follower side in the stage (b) when the material G2 is rotated reverse. The rotation of the tools is thereafter changed periodically to form the tooth td having no deviation at the tip. The blank material is thus rolled to the tooth profile having a balanced shape.

Description

【発明の詳細な説明】 本発明は歯車転造加工法の改良に係り、特に転造時に生
成される歯部両側の捲れ部と欠肉部とを矯正して均整の
とれた歯形を得られるようにし、これにより転造歯車の
精度を向上させ得る歯車転造加工法を提供しようとする
ものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a gear rolling process, and in particular, it is possible to obtain a well-balanced tooth profile by correcting the curled portions and underfill portions on both sides of the tooth portion that are generated during rolling. The present invention aims to provide a gear rolling method that can improve the precision of rolling gears.

従来、歯車を転造するには、第１図（ａ）、（ｂ）に示
すように、相対する１対の歯車工具（１）、（２）間に
被転造素材（３）を回転自在に支持し、この被転造素材
（３）に対し回転駆動される上記各歯車工具（１）、（
２）を油圧機構（４）、　（５）もしくはカム機構番こ
より押付け、該被転造素材（３）の表面に歯形を創成す
るようにしていた。Conventionally, in order to roll gears, a material to be rolled (3) is rotated between a pair of opposing gear tools (1) and (2), as shown in Figures 1(a) and (b). Each gear tool (1), (
2) is pressed by a hydraulic mechanism (4), (5) or a cam mechanism to create a tooth profile on the surface of the material to be rolled (3).

したがって、転造過°程において各歯車工具（１）　、
（２）が被転造素材（３）に接触し始めると、該各歯車
工具（１）、（２）の歯は徐々に被転造素材（３）の表
面に喰い込んセいき、上記歯は大きな圧縮力と曲げモー
メントとを受けるに至る。このとき被転造歯面には第２
図に示すように、歯元と歯先で生ずる相対すべりのため
に、歯部コロガリピッチ円を中心として矢印で示す特異
な金属流動を生じ、これがため創成される各歯のドリブ
ン側には各歯部のピッチ円を基準として外側で作用する
下向きの力（以下「下向き力」という。）によって欠肉
部（ｌｔ２）が形成され、またフォロワー側には各歯部
のピッチ円を基準として外側で作用する上向きの力（以
下「上向き力」という。）により捲れ部（２ｋ　）が形
成される。このように形成される欠肉部にも加工条件に
よってはフォロワー側に比べ僅かではあるが捲れにより
盛り上がりが生じ歯先面に乱れが生じるが、上向き力に
よる盛り上がりに対し相対的に無視し得る程度の捲れで
あるため、以後単に欠肉部と称し技術内容を説明する。Therefore, in the rolling process, each gear tool (1),
(2) starts to come into contact with the material to be rolled (3), the teeth of each gear tool (1), (2) gradually bite into the surface of the material to be rolled (3), and the teeth is subjected to large compressive forces and bending moments. At this time, the tooth surface to be rolled has a second
As shown in the figure, due to the relative slip occurring between the tooth base and the tooth tip, a unique metal flow is generated around the tooth rolling pitch circle as shown by the arrow, and as a result, each tooth is created on the driven side. A lack of thickness (lt2) is formed by a downward force (hereinafter referred to as "downward force") that acts on the outside with the pitch circle of each tooth as a reference, and on the follower side, there is a gap between the outside and the pitch circle of each tooth. A curled portion (2k) is formed by the upward force (hereinafter referred to as "upward force") that acts at . Depending on the machining conditions, the underfill area formed in this way may also bulge due to curling, albeit slightly compared to the follower side, resulting in disturbances on the tooth tip surface, but this can be ignored relative to the bulge caused by upward force. Since this is a turning-over of the area, it will be simply referred to as the missing part and the technical details will be explained hereafter.

さて、上述にような加工手段により転造歯車（Ｇ１）で
は欠肉部（１ｔ２）や捲れ部（２ｔ２）のような不整を
技術的に回避し得す必ず伴ってくるものである。これが
転造歯車（Ｇ１）の加工誤差の大きな要因をなしていた
。またこのような加工誤差が累積されると、歯車（Ｇ１
）は、第３図に示すように捲れ部（２ｔａ　）がドリブ
ン側に迄大きく延びて歯頂部に箔状部が形成されるよう
になり、したがってかかる歯車（Ｇ１）に転造後、浸炭
等により歯車の硬化処理を施すときは、上記捲れ部（２
ｔ３）が著しく脆化し、使用時には、これが歯車（Ｃ１
）から脱落して歯車（Ｇ１）の機能は著しく損なわれる
に至る。このように従来の転造加工法で得られた歯車（
Ｇ１）は転造加工特有の上記欠点を有しており、それの
対策が望まれていた。Now, with the above-mentioned processing means, it is possible to technically avoid irregularities such as the missing part (1t2) and the curled part (2t2) in the rolled gear (G1), which inevitably occur. This was a major cause of machining errors in the rolled gear (G1). Also, when such machining errors are accumulated, the gear (G1
), as shown in Fig. 3, the rolled part (2ta) extends greatly to the driven side and a foil-like part is formed on the top of the tooth. When hardening the gear with
t3) became extremely brittle, and during use, this became the gear (C1
) and the function of the gear (G1) is significantly impaired. In this way, the gears (
G1) has the above-mentioned drawbacks peculiar to rolling processing, and countermeasures have been desired.

一木発明は叙上の点を鑑み、被転造素材に歯車転造用工
具を押圧し、これら両者の相対回動により上記歯車転造
用工具の歯形に倣った歯形を上記被転造素材に付与して
所定の歯車を創成する歯車転造加工法において、上記被
転造素材に加えられる相対回転方向を間欠的に逆転させ
、この逆転成形により該被転造素材の単位歯部両側に形
成される捲れ部を均等化しようとするものであり、これ
により上記欠点を緩和して転造歯車の精度の向上を図っ
たものである。In view of the above points, the Ichiki invention presses a gear rolling tool against the material to be rolled, and by relative rotation of the two, a tooth profile that follows the tooth profile of the gear rolling tool is formed in the material to be rolled. In a gear rolling method in which a predetermined gear is created by applying a This is intended to equalize the rolled portions that are formed, thereby alleviating the above-mentioned drawbacks and improving the accuracy of the rolled gear.

以下、第４図に示す実施例に基づき本発明を説明すると
、図は、歯車（Ｇ２）の転造過程における同一部位の歯
形変化を示したものである。ここで、本実施例に係る歯
車（Ｇ２）の創成には第１図、第２図に示す、従来同様
の歯車転造用工具（１）、（２）を用いている。しかし
、本実施例に係る歯車の転造加工においては、上述のも
のとは異なり、まず素材（３）に上記工具（１）、（２
）を喰い込ませ、素材（３）を時計方向に回転させて素
材（３）表面に各歯部を盛り上がらせ、これら各歯部が
全周に亘り形成された後、更に該工具（１）、（２）を
押し伺けながら、上記素材・（３）が反時計方向に回転
するように、該工具（１）、（２）を逆回転させる工程
を採っている。この操作は加工条件に応じて間欠的に反
覆されるから、歯車の転造過程での各歯部にピッチ円よ
り外側において作用する上向き力と下向き力は、交互に
各部位で均分して繰り返し加えられ、各歯部両側にほぼ
均等の外力が作用することになる。Hereinafter, the present invention will be described based on the embodiment shown in FIG. 4. The figure shows a change in the tooth profile of the same part during the rolling process of the gear (G2). Here, gear rolling tools (1) and (2) similar to the conventional gear rolling tools (1) and (2) shown in FIGS. 1 and 2 are used to create the gear (G2) according to this embodiment. However, in the gear rolling process according to this embodiment, unlike the above-mentioned one, first, the above-mentioned tools (1) and (2) are applied to the material (3).
) and rotate the material (3) clockwise to make each tooth part bulge on the surface of the material (3), and after these teeth parts are formed over the entire circumference, the tool (1) , (2), the tools (1) and (2) are rotated in the opposite direction so that the material (3) is rotated counterclockwise. Since this operation is repeated intermittently depending on the processing conditions, the upward and downward forces that act on each tooth outside the pitch circle during the rolling process of the gear are alternately and equally divided between each part. This is applied repeatedly, resulting in approximately equal external forces acting on both sides of each tooth.

この加工過程を更に詳述すると、上記工具（１）。To explain this machining process in more detail, the above-mentioned tool (1).

（２）を素材（３）に喰い込ませ所要回転すると、素材
（３）表面には第４図（ａ）に示すような歯（ｔａ）が
素材（３）全周に形成され、このとき前述のように、各
歯（ｔａ）のドリブン側（図中左側　）には歯部中央に
向かうから矢印の金属流動により欠肉部（ｌｔａ）が生
じ、一方フォロワー側（図中右側）には、歯先および歯
元に向かう矢印の金属流動により捲れ部（２ｔａ）が形
成される。次いで上記工具（１）、（２）を押し付けな
がら上記素材（３）を逆方向に回転させると、上記歯（
ｔａ）は更に盛り−ヒげられ、第４図（ｂ）に示すよう
な歯（ｔｂ）が形成されるが、ここでは、下向き力と上
向き力の作用する方向が逆になるため、今までドリブン
側であった部位には上向き力が作用して、捲れ返りを生
じさせるフォロワー側となり突起部（ｌｔｂ）を現出さ
せ、フォロワー側であった部位には下向き力が作用し、
捲れ部（２ｔａ）は今までより抑制された突起部（２ｔ
ｂ）として形成される。このように定期的に工具（１）
、（２）の回転方向を変換させる操作を繰り返すことに
より、漸次、歯は均等に盛りｔげられ、歯（ｔｃ）を経
て歯先に片寄りのない歯（ｔｄ）を具備した歯車（Ｇ２
）へと仕上げられていくことになる。When (2) is bitten into the material (3) and rotated as required, teeth (ta) as shown in Fig. 4 (a) are formed on the surface of the material (3) around the entire circumference of the material (3). As mentioned above, on the driven side (left side in the figure) of each tooth (ta), a gap (lta) is created due to the metal flow shown by the arrow as it moves toward the center of the tooth, while on the follower side (right side in the figure) there is a gap (lta). , a rolled-up portion (2ta) is formed by the metal flow shown by the arrows toward the tooth tip and tooth root. Next, when the material (3) is rotated in the opposite direction while pressing the tools (1) and (2), the teeth (
ta) is further raised and shaved to form teeth (tb) as shown in Fig. 4(b), but here, the directions of the downward force and upward force are reversed, so An upward force acts on the part that was on the driven side, and it becomes the follower side that causes it to turn over, causing a protrusion (ltb) to appear, and a downward force acts on the part that was on the follower side,
The rolled up part (2ta) is a protrusion part (2t) that is more suppressed than before.
b) is formed as. Tools (1) regularly like this
, (2) By repeating the operation of changing the rotation direction, the teeth are gradually raised evenly, and the gear (G2) is formed by passing through the teeth (tc) and having even teeth (td) at the tips of the teeth.
).

上述のように、被転造素材（３）の回転方向を定期的に
変換させると、転造過程にある各歯部の歯面に作用する
力はその都度変化し、下向き力の作用していた部位には
上向き力が、上向き力の作用していた部位には下向き力
がそれぞれ作用することになるため、従来の転造歯車（
Ｇ１）に避は得られなかった捲れ部および欠肉部は矯正
され、本実施例の如く、歯（Ｇ２）の各歯先両面に、溝
部（３ｔｄ）を介在して、はぼ左右対称の突起部（ｌｔ
ｄ）。As mentioned above, if the direction of rotation of the material to be rolled (3) is changed periodically, the force acting on the tooth surface of each tooth part during the rolling process will change each time, and the force acting on the tooth surface of each tooth part during the rolling process will change each time. An upward force will be applied to the part where the upward force was applied, and a downward force will be applied to the part where the upward force was applied, so conventional rolled gears (
The curled parts and the missing parts that could not be avoided in G1) are corrected, and as in this example, grooves (3td) are interposed on both sides of each tooth tip of the tooth (G2) to create a more or less symmetrical shape. Projection (lt
d).

（２ｔｄ）が形成された歪みのない歯部を得ることかで
きる。(2td) can be obtained without distortion.

また、一般に、転造歯車は、歯形精度、歯すじ精度とも
に、フォロワー側で良く、ドリブン側で良好でないこと
が知られているが、本実施例によれば上述の如く、上記
工具（１）、（２）の歯形に近接した均整のとれた形状
として歯形が形成されるため、歯車（Ｇ２）の加工誤差
を大巾に抑制させることができ、該歯車（Ｇ２）は歯形
精度、歯すじ精度ともに良好なものとして形成すること
ができる。In addition, it is generally known that rolled gears have good tooth profile accuracy and tooth trace accuracy on the follower side but not on the driven side, but according to this embodiment, as described above, the tool (1) Since the tooth profile is formed as a well-proportioned shape close to the tooth profile of (2), the machining error of the gear (G2) can be greatly suppressed, and the gear (G2) has excellent tooth profile accuracy and tooth trace. It can be formed with good accuracy.

さらに、歯車精度の良否は、加工誤差の最も大きく現わ
れた部位の仕上がり具合で判断されるが、本実施例のよ
うに、均整のとれた歯（ｔｄ）が形成されるときには、
歯車（Ｇ２）の一部に、例えば従来の欠肉部のように、
加工誤差が大きく現われる部位がなく、良好な歯車とし
て形成されることとなる。また第３図に示すように、箔
状の捲れ部が形成されて、使用時に脱落するというよう
な従来の欠点はこれを全くなくすことができる。Furthermore, the quality of gear accuracy is judged by the finish of the part where the machining error is the largest, but when well-proportioned teeth (td) are formed as in this example,
For example, in a part of the gear (G2), like a conventional missing part,
There are no parts where large machining errors occur, and a good gear is formed. Furthermore, as shown in FIG. 3, the conventional drawbacks such as the formation of a foil-like rolled-up portion that falls off during use can be completely eliminated.

なお、本実施例では、はすば歯車、平歯車のいずれにも
適用され、工具（１）、（２）に関しても、単にピニオ
ン型に限らずラック型にも適用できることは言うまでも
ない。Note that this embodiment is applicable to both helical gears and spur gears, and it goes without saying that the tools (1) and (2) can also be applied not only to pinion types but also to rack types.

以上、本発明によれば、転造歯車の歯形精度および歯す
じ精度を格段に向上させ得る効果がある。As described above, according to the present invention, there is an effect that the tooth profile accuracy and tooth trace accuracy of a rolled gear can be significantly improved.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図（ａ）、（ｂ）は歯車転造装置を示す平面図およ
び正面図、第２図および第３図は第１図に示した転造装
置を適用した従来の歯車加工法による歯の創成状態をそ
れぞれ示す説明図、第４図は本発明実施例に係る創成歯
の転造過程を順次水した説明図である。 （１）、（２）・・・歯車転造用工具、（３）・・・被
転造素材、　　　（ｌｔａ）・・・欠肉部、（２ｔａ）
・・・捲れ部、　　　（Ｇ２）・・・転造歯車。 （ａ） Ｇ２ （ｃ　＞ ４図 （ｂ） （ｄ）　　・ 手続補正歯（自発） １、事件の表示 昭和５７年特許願第２０８９５９号 ２、発明の名称 １、歯車転造加工法 ３、補正をする者 事件との関係　特許出願人 住　所　　　東京都渋谷区代々木２丁目１０番１２号４
、代理人　〒１０３ 住　所　　　東京都中央区日本橋本町１丁目４番地中山
ビル４階 ５、補正の対象 明細書の特許請求の範囲の欄および発明の詳細な説明の
欄。 ６、補正の内容 （’１）明細書の特許請求の範囲の記載を別紙の通り補
正する。 （２）明細書第３頁第６行の「上述にょうな」という記
載を「上述のような」と補正する。 ７、添付書類の目録 補正後の特許請求の範囲を記載した書面　１通補正後の
特許請求の範囲を記載した書面被転造素材に歯車転造用
工具を押圧し、これら両者の相対回動により上記歯車転
造用工具の歯形に倣った歯形を上記被転造素材に付与し
て所定の歯車を創成する歯車転造加工法において、上記
被転造素材に加えられる相対回転方向を間欠的に逆転さ
せ、この逆転成形により該被転造素材の単位１両側に形
成される捲れ部を均等化することを特徴とする歯車転造
加工法。Figures 1 (a) and (b) are a plan view and a front view showing a gear rolling device, and Figures 2 and 3 are teeth produced by a conventional gear processing method using the rolling device shown in Figure 1. FIG. 4 is an explanatory diagram showing the rolling process of the created teeth according to the embodiment of the present invention. (1), (2)... Gear rolling tool, (3)... Material to be rolled, (lta)... Missing part, (2ta)
... Rolled part, (G2) ... Rolled gear. (a) G2 (c > 4 Figures (b) (d) ・ Procedural amendment teeth (voluntary) 1. Indication of the case 1982 Patent Application No. 208959 2. Title of the invention 1. Gear rolling processing method 3. Amendment Relationship with the case of a person who does
, Agent 103 Address 4th Floor 5, Nakayama Building, 1-4 Nihonbashi Honmachi, Chuo-ku, Tokyo Claims column and Detailed Description of the Invention column of the specification to be amended. 6. Contents of amendment ('1) The claims of the specification are amended as shown in the attached sheet. (2) The statement "as described above" on page 3, line 6 of the specification is amended to "as described above." 7. A document stating the scope of patent claims after amendment to the list of attached documents. 1 document stating the scope of patent claims after amendment. Pressing a gear rolling tool against the material to be rolled, and relative rotation of the two. In a gear rolling process in which a tooth profile that imitates the tooth profile of the gear rolling tool is given to the material to be rolled to create a predetermined gear, the direction of relative rotation applied to the material to be rolled is intermittently controlled. A gear rolling process characterized in that the reverse forming process equalizes the rolled portions formed on both sides of the unit 1 of the material to be rolled.

Claims (1)

【特許請求の範囲】[Claims] 被転造素材に歯車転造用工具を押圧し、これら両者の相
対回動により上記歯車転造用工具の歯形に倣った歯形を
上記被転造素材に付与して所定の歯車を創成する歯車転
造加工法において、上記被転造素材に加えられる相対回
転方向を間欠的に逆転させ、この逆転成形により該被転
造素材の単位歯車両側に形成される捲れ部を均等化する
ことを特徴とする歯車転造加工法。A gear for creating a predetermined gear by pressing a gear rolling tool against a material to be rolled and imparting a tooth profile that follows the tooth profile of the gear rolling tool to the material to be rolled by relative rotation of the two. The rolling method is characterized in that the direction of relative rotation applied to the material to be rolled is intermittently reversed, and by this reverse forming, the rolled portion formed on the unit gear wheel side of the material to be rolled is equalized. Gear rolling processing method.