JP2006320927A - Method and apparatus for manufacturing tapered bearing - Google Patents

Method and apparatus for manufacturing tapered bearing Download PDF

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Publication number
JP2006320927A
JP2006320927A JP2005145278A JP2005145278A JP2006320927A JP 2006320927 A JP2006320927 A JP 2006320927A JP 2005145278 A JP2005145278 A JP 2005145278A JP 2005145278 A JP2005145278 A JP 2005145278A JP 2006320927 A JP2006320927 A JP 2006320927A
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Prior art keywords
bearing
taper
pair
manufacturing
mandrel
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Hiroto Ohashi
寛人 大橋
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Daido Steel Co Ltd
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Daido Steel Co Ltd
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
    • F16C33/30—Parts of ball or roller bearings
    • F16C33/58—Raceways; Race rings
    • F16C33/64—Special methods of manufacture
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C19/00—Bearings with rolling contact, for exclusively rotary movement
    • F16C19/22—Bearings with rolling contact, for exclusively rotary movement with bearing rollers essentially of the same size in one or more circular rows, e.g. needle bearings
    • F16C19/34—Bearings with rolling contact, for exclusively rotary movement with bearing rollers essentially of the same size in one or more circular rows, e.g. needle bearings for both radial and axial load
    • F16C19/36—Bearings with rolling contact, for exclusively rotary movement with bearing rollers essentially of the same size in one or more circular rows, e.g. needle bearings for both radial and axial load with a single row of rollers
    • F16C19/364—Bearings with rolling contact, for exclusively rotary movement with bearing rollers essentially of the same size in one or more circular rows, e.g. needle bearings for both radial and axial load with a single row of rollers with tapered rollers, i.e. rollers having essentially the shape of a truncated cone

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Mechanical Engineering (AREA)
  • Rolling Contact Bearings (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To accurately manufacture a tapered bearing by minimizing the difference between outside diameters on the thick side and the thin side of the formed tapered bearing. <P>SOLUTION: A pair of annular blanks 1 having a fixed outside diameter the approximately half parts 11 of which are made into a thick cross section and the other approximately half parts 12 of which are made into a thin cross section are prepared. By facing the end faces 11a on the thick side to each other and performing cold rolling after these annular blanks 1 are situated between a mandrel 2 and a forming roll 3, a pair of the tapered bearings are obtained. <P>COPYRIGHT: (C)2007,JPO&amp;INPIT

Description

本発明はテーパベアリングの製造方法およびその製造装置に関し、特に、冷間ローリング加工でテーパベアリングを精度良く製造することができるテーパベアリングの製造方法とその製造装置に関する。   The present invention relates to a method for manufacturing a taper bearing and an apparatus for manufacturing the taper bearing, and more particularly to a method for manufacturing a taper bearing and an apparatus for manufacturing the taper bearing capable of accurately manufacturing the taper bearing by cold rolling.

冷間ローリング加工でテーパベアリングを製造する場合には、従来、図６に示すような略半部５１を厚肉断面に、残る略半部５２を薄肉断面にした一定外径の環状ブランク５を用意し、これを、図７に示すように、マンドレル６と成形ロール７の間に挟持して拡径圧延することにより、直線的に傾斜する内周面を有するテーパベアリング８（図８）としている。しかし、このような製造方法では、成形後のテーパベアリング８が、厚肉側より薄肉側が大径の、いわゆるラッパ形状になってしまうという問題があった。このラッパ形状は、例えば外径１５０ｍｍφ程度のテーパベアリングで、厚肉側と薄肉側の外径φ１，φ２の差（φ２−φ１）が４ｍｍほどにもなっていた。これを解決するためにブランク５の肉厚を調整し、あるいはマンドレル６と成形ロール７の相対位置を調整する等の対策を採っているが、いずれも十分な効果は得られていない。そこで、例えば特許文献１では、肉薄部と肉厚部を有する左右の粗型部を、互いの肉薄部で連接部によって連結した断面形状のリング中間品を用意し、これを冷間ローリング装置のマンドレルと成形ロールで挟持して製品形状に加工するとともに、当該冷間ローリング装置に付設したロータリカッターで連接部を切断分離して一対のテーパベアリングを得る方法が示されている。
特開２０００−３１２９４２ In the case of manufacturing a taper bearing by cold rolling, an annular blank 5 having a constant outer diameter having a substantially half portion 51 as shown in FIG. 6 in a thick section and a remaining half portion 52 as a thin section as shown in FIG. As shown in FIG. 7, the taper bearing 8 (FIG. 8) having an inner peripheral surface that is linearly inclined is obtained by sandwiching and rolling the mandrel 6 and the forming roll 7. Yes. However, such a manufacturing method has a problem that the tapered bearing 8 after molding has a so-called trumpet shape in which the thin side has a larger diameter than the thick side. The trumpet shape is, for example, a taper bearing having an outer diameter of about 150 mmφ, and the difference between the outer diameters φ1 and φ2 on the thick side and the thin side (φ2−φ1) is about 4 mm. In order to solve this problem, measures such as adjusting the thickness of the blank 5 or adjusting the relative position of the mandrel 6 and the forming roll 7 have been taken, but none of them has a sufficient effect. Therefore, in Patent Document 1, for example, a ring intermediate product having a cross-sectional shape in which the left and right rough mold parts having a thin part and a thick part are connected by a connecting part at each thin part is prepared, and this is used as a cold rolling device. A method is shown in which a mandrel and a forming roll are sandwiched and processed into a product shape, and a connecting portion is cut and separated by a rotary cutter attached to the cold rolling device to obtain a pair of tapered bearings.
JP 2000-312942

しかし、上記公報に記載の方法では、ロータリカッターを設置するために冷間ローリング装置が複雑になるとともに、ローリングと切断を同時にすることは技術的に困難なため、ローリング加工後に切断することとなって製造時間が長くなる結果、製造効率が悪く、また、切断代が必要であることから製品歩留が悪いという問題がある。   However, in the method described in the above publication, the cold rolling device is complicated to install the rotary cutter, and it is technically difficult to simultaneously perform rolling and cutting. As a result, the production time becomes long, resulting in poor production efficiency and a need for a cutting allowance, resulting in poor product yield.

そこで、本発明はこのような課題を解決するもので、装置構造の複雑化や製品歩留の悪化を生じることなく、成形されたテーパベアリングの厚肉側と薄肉側の外径差を小さく抑えてテーパベアリングを精度良く効率的に製造することができるテーパベアリングの製造方法およびその製造装置を提供することを目的とする。   Therefore, the present invention solves such a problem, and suppresses the difference in outer diameter between the thick side and the thin side of the formed tapered bearing without complicating the structure of the apparatus and deteriorating the product yield. It is an object of the present invention to provide a taper bearing manufacturing method and a manufacturing apparatus thereof that can manufacture a taper bearing with high accuracy and efficiency.

上記目的を達成するために、本第１発明の製造方法では、軸方向の略半部（１１）を厚肉断面とし、他の略半部（１２）を薄肉断面とした一定外径の環状ブランク（１）を一対用意し、これら環状ブランク（１）を、互いに厚肉側の端面（１１ａ）を対向させてマンドレル（２）と成形ロール（３）の間に位置させて冷間ローリング加工することにより一対のテーパベアリングを得る。本第１発明においては、厚肉側の端面を対向させてマンドレルと成形ロールの間に一対の環状ブランクを位置させているから、圧延成形時に環状ブランクの姿勢が偏向することは防止され、この結果、成形されたテーパベアリングのラッパ形状が抑えられる。そして、ロータリカッターを設置する必要が無いから装置構造が複雑化することはなく、また製造効率も良い。また、切断代が不要であるから製品歩留が向上する。   In order to achieve the above object, in the manufacturing method according to the first aspect of the present invention, an annular having a constant outer diameter in which the substantially half part (11) in the axial direction has a thick cross section and the other substantially half part (12) has a thin cross section. A pair of blanks (1) is prepared, and these annular blanks (1) are positioned between the mandrel (2) and the forming roll (3) with the end faces (11a) on the thick side facing each other, and cold rolling is performed. By doing so, a pair of taper bearings is obtained. In the first invention, since the pair of annular blanks are positioned between the mandrel and the forming roll with the end surfaces on the thick side facing each other, it is possible to prevent the posture of the annular blank from being deflected during rolling forming. As a result, the trumpet shape of the formed taper bearing is suppressed. And since it is not necessary to install a rotary cutter, the apparatus structure does not become complicated, and the production efficiency is good. Further, since the cutting allowance is unnecessary, the product yield is improved.

本第２発明の製造装置では、上記一対の環状ブランク（１）を位置させるマンドレル（２）の成形部（２１）と成形ロール（３）の受け部につき、成形部（２１）を、整形されるテーパベアリング（１）のテーパ面に沿った直線傾斜面を有する三角溝形状とするとともに、受け部（３１）を、成形されるテーパベアリング（１）の２個分の外周幅に略等しい幅で一定深さで凹陥する形状とする。   In the manufacturing apparatus of the second invention, the molding part (21) is shaped with respect to the molding part (21) of the mandrel (2) for positioning the pair of annular blanks (1) and the receiving part of the molding roll (3). The tapered bearing (1) has a triangular groove shape having a linearly inclined surface along the tapered surface, and the receiving portion (31) has a width substantially equal to the outer peripheral width of the two tapered bearings (1) to be formed. The shape is recessed at a certain depth.

本第３発明では、上記マンドレル成形部（２１）と上記受け部（３１）の各中央位置全周に凸条（２２，３２）を形成する。本第３発明においては、凸条の存在によって、成形されたテーパベアリングの厚肉側内周部に生じることがある割れが効果的に防止される。   In this 3rd invention, a protruding item | line (22, 32) is formed in each center position perimeter of the said mandrel shaping | molding part (21) and the said receiving part (31). In this 3rd invention, the crack which may arise in the thick wall side inner peripheral part of the shape | molded taper bearing is effectively prevented by presence of a protruding item | line.

なお、上記カッコ内の符号は、後述する実施形態に記載の具体的手段との対応関係を示すものである。   In addition, the code | symbol in the said parenthesis shows the correspondence with the specific means as described in embodiment mentioned later.

以上のように、本発明によれば、成形されたテーパベアリングの厚肉側と薄肉側の外径差を小さく抑えてテーパベアリングを精度良く製造することができる。   As described above, according to the present invention, the taper bearing can be manufactured with high accuracy while suppressing the difference in the outer diameter between the thick side and the thin side of the formed tapered bearing.

（第１実施形態）
本発明の製造方法では、鍛造によって図１に示すような従来とほぼ同様の断面の環状ブランク１を成形する。すなわち、環状ブランク１は外径が一定で、その軸方向の略半部１１が厚肉となり、残る略半部１２が、上記略半部１１の一部に形成した小幅のテーパ部１３を経て漸次薄肉となっている。このような環状ブランク１を一対用意して、これらを図２に示すように、互いの厚肉側の端面１１ａを対向させてマンドレル２と成形ロール３の間に位置させる。この場合の成形ロール３外周面の受け部３１は、成形されるテーパベアリング１の２個分の外周幅に略等しい幅で一定深さで凹陥している。一方、上記受け部３１に対応するマンドレル２外周の成形部２１は、成形されるテーパベアリングのテーパ面に沿った直線傾斜面を有する三角溝形状としてある。 (First embodiment)
In the manufacturing method of the present invention, an annular blank 1 having a cross section substantially similar to the conventional one as shown in FIG. 1 is formed by forging. That is, the outer diameter of the annular blank 1 is constant, the substantially half part 11 in the axial direction is thick, and the remaining substantially half part 12 passes through the narrow taper part 13 formed in a part of the substantially half part 11. Gradually thin. A pair of such annular blanks 1 is prepared, and these are positioned between the mandrel 2 and the forming roll 3 with the end surfaces 11a on the thick side facing each other as shown in FIG. In this case, the receiving portion 31 on the outer peripheral surface of the forming roll 3 is recessed at a constant depth with a width substantially equal to the outer peripheral width of the two tapered bearings 1 to be formed. On the other hand, the molding portion 21 on the outer periphery of the mandrel 2 corresponding to the receiving portion 31 has a triangular groove shape having a linearly inclined surface along the tapered surface of the tapered bearing to be molded.

このようなマンドレル２を成形ロール３に接近させて環状ブランク１を押圧し圧延拡径させると、各環状ブランク１がそれぞれ図３に示すようなテーパベアリング４に成形される。このような方法で成形された各テーパベアリング４は、外径１５０ｍｍφ程度のもので厚肉側と薄肉側の外径φ１，φ２の差（φ２−φ１）が１．５ｍｍ程度と十分小さく抑えられ、ラッパ形状が解消される。   When such a mandrel 2 is brought close to the forming roll 3 and the annular blank 1 is pressed and rolled to expand the diameter, each annular blank 1 is formed into a tapered bearing 4 as shown in FIG. Each tapered bearing 4 formed by such a method has an outer diameter of about 150 mmφ, and the difference between the outer diameters φ1 and φ2 (φ2−φ1) between the thick side and the thin side can be suppressed to about 1.5 mm. The trumpet shape is eliminated.

ちなみに、図４に示すように、一対の環状ブランク１の互いの薄肉側の端面１２ａを対向させてマンドレル２と成形ロール３の間に位置させ成形した場合には、成形された各テーパベアリングの厚肉側と薄肉側の外径差は、外径１５０ｍｍφ程度のもので従来と同程度の４ｍｍ程度の大きさとなり、ラッパ形状は解消されない。   By the way, as shown in FIG. 4, when the pair of annular blanks 1 are formed with the thin-walled end faces 12 a facing each other and positioned between the mandrel 2 and the forming roll 3, The difference in outer diameter between the thick side and the thin side is about 150 mmφ and about 4 mm, which is the same as the conventional size, and the trumpet shape is not solved.

（第２実施形態）
図５に示すように、マンドレル２の成形部２１中央と成形ロール３の受け部３１中央の全周にそれぞれ凸条２２，３２を形成しておくと、成形されたテーパベアリング４の厚肉側内周部（図３のＡ部）に生じることがある割れを効果的に防止することができる。 (Second Embodiment)
As shown in FIG. 5, if the ridges 22 and 32 are formed on the entire circumference of the center of the forming portion 21 of the mandrel 2 and the center of the receiving portion 31 of the forming roll 3, the thicker side of the formed tapered bearing 4 is formed. The crack which may arise in an inner peripheral part (A part of FIG. 3) can be prevented effectively.

本発明の第１実施形態における環状ブランクの一例を示す断面図である。It is sectional drawing which shows an example of the annular blank in 1st Embodiment of this invention. テーパベアリング成形時の断面図である。It is sectional drawing at the time of taper bearing shaping | molding. 成形されたテーパベアリングの断面図である。It is sectional drawing of the shape | molded taper bearing. 比較例を示すテーパベアリング成形時の概略断面図である。It is a schematic sectional drawing at the time of taper bearing shaping | molding which shows a comparative example. 本発明の第２実施形態における製造装置の要部平面図である。It is a principal part top view of the manufacturing apparatus in 2nd Embodiment of this invention. 従来の環状ブランクの一例を示す断面図である。It is sectional drawing which shows an example of the conventional annular blank. 従来のテーパベアリング成形時の断面図である。It is sectional drawing at the time of the conventional taper bearing shaping | molding. 従来のテーパベアリングの断面図である。It is sectional drawing of the conventional taper bearing.

符号の説明Explanation of symbols

１…環状ブランク、１１，１２…略半部、１１ａ…端面、２…マンドレル、２１…成形部、２２…凸条、３…整形ロール、３１…受け部、３２…凸条。 DESCRIPTION OF SYMBOLS 1 ... Circular blank, 11, 12 ... Almost half part, 11a ... End surface, 2 ... Mandrel, 21 ... Molding part, 22 ... Convex strip, 3 ... Shaping roll, 31 ... Receiving part, 32 ... Convex strip.

Claims (3)

軸方向の略半部を厚肉断面とし、他の略半部を薄肉断面とした一定外径の環状ブランクを一対用意し、これら環状ブランクを、互いに厚肉側の端面を対向させてマンドレルと成形ロールの間に位置させて冷間ローリング加工することにより一対のテーパベアリングを得ることを特徴とするテーパベアリングの製造方法。 Prepare a pair of annular blanks with a constant outer diameter with a thick half cross-section in the axial direction and a thin cross-section in the other half, and connect these annular blanks to the mandrel with the end faces on the thick side facing each other. A method of manufacturing a taper bearing, characterized in that a pair of taper bearings are obtained by cold rolling processing between the forming rolls. 前記一対の環状ブランクを位置させる前記マンドレルの成形部と前記成形ロールの受け部につき、前記成形部を、整形される前記テーパベアリングのテーパ面に沿った直線傾斜面を有する三角溝形状とするとともに、前記受け部を、成形されるテーパベアリングの２個分の外周幅に略等しい幅で一定深さで凹陥する形状とした請求項１に記載の製造方法に使用するテーパベアリングの製造装置。 About the molding part of the mandrel for positioning the pair of annular blanks and the receiving part of the molding roll, the molding part has a triangular groove shape having a linearly inclined surface along the tapered surface of the tapered bearing to be shaped. 2. The taper bearing manufacturing apparatus used in the manufacturing method according to claim 1, wherein the receiving portion is shaped to be recessed at a constant depth with a width substantially equal to an outer peripheral width of two taper bearings to be molded. 前記成形部と前記受け部の各中央位置全周に凸条を形成した請求項２に記載のテーパベアリングの製造装置。 The manufacturing apparatus of the taper bearing of Claim 2 which formed the protruding item | line on the perimeter of each center position of the said shaping | molding part and the said receiving part.
JP2005145278A 2005-05-18 2005-05-18 Method and apparatus for manufacturing tapered bearing Pending JP2006320927A (en)

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ITTO20130145A1 (en) * 2013-02-21 2014-08-22 Skf Ab COLD SPRAYING PROCEDURE FOR BEARING RING FORMING
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Publication number Priority date Publication date Assignee Title
KR101079729B1 (en) 2009-01-30 2011-11-04 손유홍 Ring mill apparatus for deformed inner diameter portion and deformed ring manufacturing method using the same
ITTO20130145A1 (en) * 2013-02-21 2014-08-22 Skf Ab COLD SPRAYING PROCEDURE FOR BEARING RING FORMING
EP2769781A1 (en) * 2013-02-21 2014-08-27 Aktiebolaget SKF A cold rolling method for forming bearing rings
WO2015136911A1 (en) * 2014-03-12 2015-09-17 日本精工株式会社 Rolling device and rolling method
CN105916610A (en) * 2014-03-12 2016-08-31 日本精工株式会社 Rolling device and rolling method
JPWO2015136911A1 (en) * 2014-03-12 2017-04-06 日本精工株式会社 Rolling apparatus and rolling method
CN105916610B (en) * 2014-03-12 2018-05-25 日本精工株式会社 Roll processing device and rolling and processing method
CN104942198A (en) * 2014-03-26 2015-09-30 无锡隆迪精密锻件有限公司 Die structure for producing race for large mine car wheel
CN104942198B (en) * 2014-03-26 2017-07-14 无锡隆迪精密锻件有限公司 A kind of mould structure for being used to produce large-scale mine wheel seat ring
JP2020044575A (en) * 2018-09-21 2020-03-26 共栄精工株式会社 Ring molding device, and ring molding method
JP7079491B2 (en) 2018-09-21 2022-06-02 共栄精工株式会社 Ring forming device and ring forming method

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