JP2003120681A - Method for manufacturing resin ball retainer for bearing - Google Patents

Method for manufacturing resin ball retainer for bearing

Info

Publication number
JP2003120681A
JP2003120681A JP2001320266A JP2001320266A JP2003120681A JP 2003120681 A JP2003120681 A JP 2003120681A JP 2001320266 A JP2001320266 A JP 2001320266A JP 2001320266 A JP2001320266 A JP 2001320266A JP 2003120681 A JP2003120681 A JP 2003120681A
Authority
JP
Japan
Prior art keywords
pocket
peripheral surface
inner peripheral
resin ball
ball retainer
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
Application number
JP2001320266A
Other languages
Japanese (ja)
Inventor
Shigenobu Fujimoto
成信 藤本
Kiyoshi Yamamoto
喜芳 山本
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nakanishi Metal Works Co Ltd
Original Assignee
Nakanishi Metal Works Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Nakanishi Metal Works Co Ltd filed Critical Nakanishi Metal Works Co Ltd
Priority to JP2001320266A priority Critical patent/JP2003120681A/en
Publication of JP2003120681A publication Critical patent/JP2003120681A/en
Pending legal-status Critical Current

Links

Classifications

    • 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
    • F16C33/38—Ball cages
    • F16C33/41—Ball cages comb-shaped
    • F16C33/412—Massive or moulded comb cages, e.g. snap ball cages
    • F16C33/414—Massive or moulded comb cages, e.g. snap ball cages formed as one-piece cages, i.e. monoblock comb cages
    • F16C33/416—Massive or moulded comb cages, e.g. snap ball cages formed as one-piece cages, i.e. monoblock comb cages made from plastic, e.g. injection moulded comb cages
    • 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
    • F16C33/38—Ball cages
    • F16C33/41—Ball cages comb-shaped
    • F16C33/418—Details of individual pockets, e.g. shape or ball retaining means
    • 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
    • F16C33/66—Special parts or details in view of lubrication
    • F16C33/6637—Special parts or details in view of lubrication with liquid lubricant
    • F16C33/664—Retaining the liquid in or near the bearing
    • F16C33/6651—Retaining the liquid in or near the bearing in recesses or cavities provided in retainers, races or rolling elements
    • 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
    • F16C19/02—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows
    • F16C19/04—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows for radial load mainly
    • F16C19/06—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows for radial load mainly with a single row or balls
    • 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
    • F16C2220/00—Shaping
    • F16C2220/02—Shaping by casting
    • F16C2220/04—Shaping by casting by injection-moulding

Landscapes

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

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a ball retainer capable of easily manufacturing the retainer at low costs, a resin ball retainer excellent in retaining property of lubricant, and capable of obtaining sufficient dimensional precision of an inner peripheral surfaces of pockets. SOLUTION: This method for manufacturing the resin ball retainer for the bearing is intended to manufacture by injection molding a resin ball retainer 10 arranged along a peripheral direction on an annular body 11 with the pockets 12 opening to one side axially of the annular body 11, and retaining rotationally the balls. A finely recessed and protruding processed portions 25 are previously formed by electric discharge machining on an outer periphery surface of a pocket forming die element 20 for forming the pockets 12 in the injection moulding die. During injection moulding, finely recessed and protruding portions 15 for retaining oil are formed by transferring the finely recessed and protruding processed portions 25 on the inner peripheral surfaces of the pockets 12 during the injection moulding.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【発明の属する技術分野】この発明は、転がり玉軸受の
内輪及び外輪間に、ボールを転動自在に保持した状態に
組み込まれる冠形の樹脂製玉保持器の製造方法に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a crown-shaped resin ball retainer which is incorporated in a state in which balls are rotatably held between an inner ring and an outer ring of a rolling ball bearing.

【０００２】[0002]

【従来の技術】図４に示すように、転がり玉軸受（５）
は、内輪（６）及び外輪（７）間に複数のボール（８）
が転動自在に保持されるものであるが、これらの複数の
ボール（８）を周方向に等間隔おきに保持するために玉
保持器（１）が用いられる。2. Description of the Related Art As shown in FIG. 4, rolling ball bearings (5)
Is a plurality of balls (8) between the inner ring (6) and the outer ring (7)
Is rotatably held, and a ball retainer (1) is used to hold the plurality of balls (8) at equal intervals in the circumferential direction.

【０００３】近年、このような玉保持器（１）として、
軽量化、低コスト化を図るために、図５ないし図７に示
すように、冠形の樹脂製玉保持器（１）が採用される傾
向が高くなっている。In recent years, as such a ball cage (1),
In order to reduce the weight and the cost, as shown in FIGS. 5 to 7, there is an increasing tendency to adopt a crown-shaped resin ball retainer (1).

【０００４】この玉保持器（１）は、環状体（２）を具
備し、環状体（２）における軸方向の一方側に、その一
方側に向けて開口する複数のポケット（３）が周方向に
所定間隔おきに形成されている。そしてこの玉保持器
（１）が、ポケット（３）内にボール（８）を転動自在
に保持した状態で内輪（６）及び外輪（７）間に組み込
まれて、軸受（５）が形成されるものである。This ball retainer (1) is provided with an annular body (2), and a plurality of pockets (3) opening toward one side in the axial direction of the annular body (2) are formed around the one side in the axial direction. It is formed at predetermined intervals in the direction. The ball retainer (1) is mounted between the inner ring (6) and the outer ring (7) in a state where the ball (8) is rotatably held in the pocket (3) to form a bearing (5). It is what is done.

【０００５】このような玉軸受（５）においては、玉保
持器（１）におけるポケット（３）の内周面に、グリー
ス等の潤滑剤を注入することにより、ボール（８）と、
保持器（１）、内輪（６）及び外輪（７）等の周囲接触
部位との間の摩擦抵抗を減少させて、安定した回転状態
が得られるように配慮されている。In such a ball bearing (5), by injecting a lubricant such as grease into the inner peripheral surface of the pocket (3) of the ball cage (1), the balls (8) and
The frictional resistance between the cage (1), the inner ring (6), the outer ring (7), and the like is reduced, so that a stable rotation state can be obtained.

【０００６】[0006]

【発明の背景】ところで、本発明者は、上記のような樹
脂製玉保持器（１）に対し、その性能向上を目的とし
て、分析を行ったところ、従来の軸受では、玉保持器
（１）のポケット内周面が平滑面に仕上げられている。
このため、そのポケット内周面における潤滑剤の保持力
が低くなり、ポケット内周面に注入される潤滑剤の減少
が早期に進行し、潤滑が不十分となり、摩擦抵抗が増大
して軸受性能が低下することが判明した。詳述すると、
従来の樹脂製玉保持器（１）は、射出成形によって製造
されるのが通例であるが、この射出成形における成形後
の型開きにおいて、保持器としての樹脂成形品を取り出
す際に、離型性を向上させるために、金型表面は可及的
に平滑に形成されている。このため、成形される玉保持
器（１）の表面が平滑に形成され、当然のことながら、
ポケット内周面も平滑に形成されるので、潤滑剤の保持
力が低下し、上記した潤滑剤減少の問題が発生すること
が判明した。By the way, the present inventor analyzed the above-described resin ball cage (1) for the purpose of improving its performance. ) The inner peripheral surface of the pocket is finished to be smooth.
Therefore, the retaining force of the lubricant on the inner peripheral surface of the pocket becomes low, the amount of the lubricant injected into the inner peripheral surface of the pocket progresses early, the lubrication becomes insufficient, and the frictional resistance increases to increase the bearing performance. Was found to decrease. In detail,
The conventional resin ball retainer (1) is usually manufactured by injection molding, but when the resin molded product as the retainer is taken out during mold opening after molding in this injection molding, the mold release is performed. The mold surface is formed as smooth as possible in order to improve the property. For this reason, the surface of the ball cage (1) to be molded is made smooth, and as a matter of course,
It has been found that the inner peripheral surface of the pocket is also formed smoothly, so that the retaining force of the lubricant is reduced and the above-mentioned problem of the lubricant reduction occurs.

【０００７】参考までに、上記従来の玉保持器（１）に
おけるポケット内周面の面粗さ（Ｒmax ）を測定したと
ころ、１〜３μｍであった。For reference, the surface roughness (Rmax) of the inner peripheral surface of the pocket in the conventional ball cage (1) was measured and found to be 1 to 3 μm.

【０００８】[0008]

【発明が解決しようとする課題】上記の分析結果を基
に、本発明者は潤滑剤の保持性能を向上させるための手
段を種々検討していくうち、玉保持器（１）のポケット
内周面を粗面に仕上げるという構成を見出した。On the basis of the above analysis results, the present inventor has been investigating various means for improving the retention performance of the lubricant, and as a result, has examined the inner circumference of the pocket of the ball cage (1). We have found a structure that finishes the surface to a rough surface.

【０００９】その構成を具現化するために、まず、射出
成形後の保持器（１）のポケット内周面に、バレル加工
を施して、ポケット内周面に微細な凹凸部を形成する技
術を試みた。しかしながら、この試行技術においては、
射出成形後に、バレル加工を別途施す必要があるため、
作業工数が増加して、保持器の製作が困難になるばかり
か、生産コストの増大を来す恐れがあるという結論に至
った。In order to embody the structure, first, a technique for forming a minute uneven portion on the pocket inner peripheral surface by barreling the pocket inner peripheral surface of the cage (1) after injection molding is described. I tried. However, in this trial technique,
After injection molding, barrel processing needs to be performed separately,
It was concluded that not only would it be difficult to manufacture the cage due to the increased number of work steps, but also the production cost would increase.

【００１０】また、他の試行技術として、射出成形用金
型におけるポケット形成用の金型素子の外周面に、ショ
ットブラスト加工により、あらかじめ微細凹凸加工部を
形成しておき、射出成形時に上記微細凹凸加工部の転写
によって、ポケット内周面に油保持用の微細凹凸部を形
成する技術を試行した。As another trial technique, a fine concavo-convex processed portion is previously formed by shot blasting on the outer peripheral surface of a mold element for forming a pocket in an injection molding die, and the above-mentioned fine portion is formed at the time of injection molding. An attempt was made on a technique for forming a fine uneven portion for retaining oil on the inner peripheral surface of the pocket by transferring the uneven processed portion.

【００１１】この試行技術においては、射出成形と同時
に、ポケット内周面に微細加工部が転写されるものであ
るため、作業工数は増加せず、製作容易性及びコスト削
減を期待することができる。In this trial technique, since the finely processed portion is transferred onto the inner peripheral surface of the pocket at the same time as the injection molding, the number of working steps does not increase, and the easiness of manufacturing and cost reduction can be expected. .

【００１２】しかしながら、ショットブラスト加工によ
り得られた微細凹凸加工部は、凹凸度合のばらつきが大
きいため、その加工部の転写によって得られる微細凹凸
部においても、凹凸度合のばらつきが大きくなる。この
ため、ポケット内周面を高い寸法精度に仕上げることが
困難となり、ボール（８）を位置精度良く安定状態に保
持することが困難であるという結論に至った。However, since the fine concavo-convex processed portion obtained by the shot blasting process has a large variation in the concavo-convex degree, the fine concavo-convex portion obtained by transferring the processed portion also has a large irregularity degree. Therefore, it has been difficult to finish the inner peripheral surface of the pocket with high dimensional accuracy, and it has been concluded that it is difficult to maintain the ball (8) in a stable state with high positional accuracy.

【００１３】特にパーソナルコンピュータ用ハードディ
スク装置等の精密機器に採用される小径の玉軸受では、
保持器（１）のポケット寸法も小さいため、僅かでも、
位置精度が低下すると、ボール（８）とその周囲の接触
部位との間の接触圧に偏りが生じて異音が発生したり、
偏摩耗により早期劣化が生じる等の不具合が懸念される
ところである。In particular, in a small diameter ball bearing used in precision equipment such as a hard disk drive for a personal computer,
Since the cage (1) has a small pocket size,
When the positional accuracy is lowered, the contact pressure between the ball (8) and the contact portion around the ball (8) becomes uneven, and abnormal noise is generated.
There is concern about problems such as early deterioration due to uneven wear.

【００１４】この発明は、上記の事情に鑑みてなされた
もので、潤滑剤の保持性能に優れるとともに、ポケット
内周面の寸法精度を十分に得ることができる樹脂製玉保
持器を簡単かつ低コストで製造することができる軸受用
樹脂製玉保持器の製造方法を提供することを目的とす
る。The present invention has been made in view of the above circumstances, and has a simple and low-priced resin ball retainer that is excellent in the ability to retain a lubricant and can sufficiently obtain the dimensional accuracy of the inner peripheral surface of the pocket. An object of the present invention is to provide a method for manufacturing a resin ball cage for bearings that can be manufactured at low cost.

【００１５】[0015]

【課題を解決するための手段】本発明者は、樹脂製玉保
持器に関して、綿密な実験、研究を引き続き行った結
果、上記の目的を達成可能な特有の構成を見出し、本発
明をなすに至った。The inventor of the present invention found a peculiar structure capable of achieving the above-mentioned object as a result of thorough experiments and researches on resin ball cages, and made the present invention. I arrived.

【００１６】すなわち本発明は、環状体に、その軸方向
の一方側に開口し、かつボールを転動自在に保持する複
数のポケットが周方向に沿って設けられた樹脂製玉保持
器を射出成形により製造する方法であって、射出成形用
金型における前記ポケットを形成するためのポケット形
成用金型素子の外周面に、放電加工によって、あらかじ
め微細凹凸加工部を形成しておき、射出成形時に、前記
ポケットの内周面に、前記微細凹凸加工部の転写によっ
て油保持用微細凹凸部を形成するものを要旨としてい
る。That is, the present invention ejects a resin ball retainer in which a plurality of pockets, which are open to one side in the axial direction of the annular body and hold balls so that they can roll, are provided in the annular body along the circumferential direction. A method of manufacturing by molding, wherein a fine concavo-convex processed portion is previously formed by electrical discharge machining on the outer peripheral surface of a pocket forming die element for forming the pocket in an injection molding die, and injection molding is performed. At the time, the gist is to form the oil-holding fine concave-convex portion on the inner peripheral surface of the pocket by transferring the fine concave-convex processed portion.

【００１７】本発明の軸受用樹脂製玉保持器の製造方法
においては、ポケット内周面に微細凹凸部が形成される
ため、そのポケット内周面における潤滑剤の保持性能を
向上させることができる。In the method of manufacturing the resin ball cage for bearings of the present invention, since the fine irregularities are formed on the inner peripheral surface of the pocket, the performance of retaining the lubricant on the inner peripheral surface of the pocket can be improved. .

【００１８】また、ポケット形成用金型素子の外周面
に、放電加工によりあらかじめ微細凹凸加工部を形成し
ておき、射出成形時に、上記微細凹凸加工部の転写によ
りポケット内周面に油保持用微細凹凸部を形成するもの
であるため、ポケット内周面の微細凹凸部を、射出成形
と同時に形成することができ、微細凹凸部の形成用に別
途加工を施す必要がなく、作業工程数が増加するのを防
止することができる。Further, a fine concavo-convex portion is formed in advance on the outer peripheral surface of the pocket forming die element by electric discharge machining, and during injection molding, the fine concavo-convex portion is transferred to retain oil on the inner peripheral surface of the pocket. Since the fine concavo-convex portion is formed, the fine concavo-convex portion on the inner peripheral surface of the pocket can be formed at the same time as the injection molding. It can be prevented from increasing.

【００１９】更に、高精度の加工が可能な放電加工を用
いて金型素子に微細凹凸加工部を形成するものであるた
め、加工部における凹凸度合のばらつきが少なくなり、
高い寸法精度の金型素子を形成することができる。従っ
て、この金型素子によって成形されるポケット内周面を
高い寸法精度に仕上げることができ、ボールを位置精度
良く安定状態に確実に保持することができる。Further, since the fine unevenness processed portion is formed on the die element by using the electric discharge machining capable of highly accurate processing, the unevenness of the unevenness in the processed portion is reduced,
A mold element with high dimensional accuracy can be formed. Therefore, the inner peripheral surface of the pocket molded by the mold element can be finished with high dimensional accuracy, and the ball can be reliably held in a stable state with high positional accuracy.

【００２０】一方、本発明においては、前記ポケット形
成用金型素子の微細凹凸加工部における面粗さ（Ｒmax
）が１０〜２０μｍに設定されてなる構成を採用する
のが好ましい。On the other hand, in the present invention, the surface roughness (Rmax at the finely textured portion of the pocket forming mold element is Rmax.
It is preferable to adopt a configuration in which) is set to 10 to 20 μm.

【００２１】すなわちこの構成を採用する場合には、ポ
ケット内周面における潤滑剤の保持性能を十分に確保し
つつ、高い寸法精度を得ることができる。That is, when this structure is adopted, high dimensional accuracy can be obtained while sufficiently retaining the lubricant on the inner peripheral surface of the pocket.

【００２２】ここで、本発明において、放電加工は、金
型素子等の金属製の被加工物と、加工工具としての電極
との間に、絶縁媒体としての放電加工液を介して電圧を
印加して火花放電を行い、その際の高温度によって被加
工物の表面層を微細に溶融除去していく加工である。In the present invention, in the electric discharge machining, a voltage is applied between a metal workpiece such as a die element and an electrode as a machining tool through an electric discharge machining liquid as an insulating medium. Then, spark discharge is performed, and the high temperature at that time finely melts and removes the surface layer of the workpiece.

【００２３】この放電加工は、熱的な加工であるため、
ショットブラスト加工やバレル加工等の機械加工とは違
って、切削困難な高硬度の金属材料であっても精度良く
加工することができるとともに、精密加工、曲面加工、
球体加工等も精度良く行うことができる。Since this electric discharge machining is a thermal machining,
Unlike mechanical processing such as shot blasting and barrel processing, even high hardness metal materials that are difficult to cut can be processed with high precision, precision processing, curved surface processing,
Sphere processing and the like can be performed with high precision.

【００２４】なお、放電加工は、被加工物と電極との間
の隙間（放電ギャップ）を適宜変更することにより、放
電加工面の粗さを自在に調整することができる上、凹凸
度合のばらつきが少ない梨地状の加工面を得ることがで
きる。In the electric discharge machining, the roughness of the electric discharge machined surface can be freely adjusted by appropriately changing the gap (discharge gap) between the workpiece and the electrode, and the unevenness degree can be varied. It is possible to obtain a satin-finished processed surface with a small amount.

【００２５】[0025]

【発明の実施の形態】図１はこの発明の実施形態の製造
方法によって製造された樹脂製玉保持器（１０）を示す
斜視図、図２はその保持器（１０）におけるポケット周
辺を拡大して示す斜視図である。両図に示すように、こ
の玉保持器（１０）は、射出成形により得られる合成樹
脂製の冠形のものであり、環状体（１１）を具備し、そ
の環状体（１１）に、軸方向の一方側に向けて開口し、
かつボールを転動自在に収容保持するための複数のポケ
ット（１２）が周方向に等間隔おきに形成されている。
更にポケット（１２）の内周面には、後に詳述する梨地
状の油保持用微細凹凸部（１５）が形成されている。1 is a perspective view showing a resin ball retainer (10) manufactured by a manufacturing method according to an embodiment of the present invention, and FIG. 2 is an enlarged view of a pocket periphery of the retainer (10). FIG. As shown in both figures, this ball cage (10) is a synthetic resin crown type obtained by injection molding, and is provided with an annular body (11), and the annular body (11) has a shaft. Open towards one side of the direction,
In addition, a plurality of pockets (12) for rollingly accommodating and holding balls are formed at equal intervals in the circumferential direction.
Furthermore, on the inner peripheral surface of the pocket (12), a fine satin-like oil-holding uneven portion (15), which will be described in detail later, is formed.

【００２６】本実施形態の玉保持器（１０）を製造する
ための射出成形用金型としては、冠形樹脂保持器の製造
の際に一般に用いられるものを利用でき、例えば上下に
配置された金型が軸方向に開放するアキシャルドロータ
イプの金型を好適に使用することができる。As the injection molding die for manufacturing the ball cage (10) of the present embodiment, those generally used in manufacturing the crown-shaped resin cage can be used, and for example, they are arranged vertically. An axial draw type mold in which the mold is opened in the axial direction can be preferably used.

【００２７】この金型は、例えば固定側の下型と、可動
側の上型との対向面に、保持器形状に対応したキャビテ
ィーが設けられるとともに、可動型の対向面側には、保
持器ポケット形成用に本実施形態特有のポケット形成用
金型素子（２０）が組み込まれている。In this metal mold, for example, a cavity corresponding to the shape of a cage is provided on the facing surface of a fixed lower mold and a movable upper mold, and a holding mold is provided on the facing surface of the movable mold. A pocket forming mold element (20) specific to the present embodiment is incorporated for forming a container pocket.

【００２８】この金型素子（２０）は、図３に示すよう
に、保持器（１０）のポケット（１２）の内周形状に対
応する部分球体（２１）と、その球体（２１）に一端が
連結されたロッド（２２）とを備えている。As shown in FIG. 3, the mold element (20) has a partial sphere (21) corresponding to the inner peripheral shape of the pocket (12) of the retainer (10) and one end of the sphere (21). And a rod (22) connected to each other.

【００２９】ここで、本実施形態においては、部分球体
（２１）の外周面には、放電加工により梨地状の微細凹
凸加工部（２５）が形成されている。すなわち、絶縁媒
体としての放電加工油等の液中において、金型素子（２
０）の部分球体（２１）と銅製等の電極とを相対配置さ
せ、金型素子（２０）側をアースに接続するとともに、
電極側を電源に接続して、両者間に電圧を印加する。こ
れにより、部分球体（２１）と電極との間にアーク放電
を生じさせてその際の高温度によって、部分球体（２
１）の外表面部を微細に溶融除去し、部分球体（２１）
の外周面に、微細凹凸加工部（２５）を形成し、梨地状
の粗面に仕上げるものである。Here, in this embodiment, a fine textured processed portion (25) having a satin finish is formed on the outer peripheral surface of the partial sphere (21) by electric discharge machining. That is, the mold element (2
The partial sphere (21) of 0) and the electrode made of copper or the like are arranged so as to be connected to each other, and the mold element (20) side is connected to the ground.
The electrode side is connected to a power source and a voltage is applied between the two. As a result, arc discharge is generated between the partial sphere (21) and the electrode, and due to the high temperature at that time, the partial sphere (2
Partially spherical body (21) by finely melting and removing the outer surface part of 1)
A finely textured processed portion (25) is formed on the outer peripheral surface of, and the surface is finished to have a satin rough surface.

【００３０】なお、放電加工に用いられる電極として
は、例えば部分球体（２１）の外周面に対応した所定の
曲率を有する内球面（凹球面）形状のもの等を用いるこ
とにより、一度の放電加工により部分球体（２１）の所
要領域全域に微細凹凸加工部（２５）を形成することが
できる。As the electrode used for electric discharge machining, for example, an electrode having an inner spherical surface (concave spherical surface) shape having a predetermined curvature corresponding to the outer peripheral surface of the partial spherical body (21) can be used to perform electric discharge machining once. Thus, the fine concavo-convex processed portion (25) can be formed in the entire required region of the partial sphere (21).

【００３１】また本実施形態においては、放電加工によ
って、部分球体（２１）の外表面部が切削除去されるた
め、その除去部分及び除去量等をあらかじめ考慮して、
放電加工前の部分球体（２１）の寸法を設定しておく。
つまり、放電加工によって、部分球体（２１）の外周面
における最終寸法仕上げも同時に行うものである。In the present embodiment, the outer surface of the partial sphere (21) is cut and removed by electric discharge machining. Therefore, the removed portion and the removed amount are taken into consideration in advance.
The dimensions of the partial sphere (21) before electric discharge machining are set.
That is, the final dimension finishing on the outer peripheral surface of the partial sphere (21) is also simultaneously performed by electric discharge machining.

【００３２】また本実施形態において、微細凹凸加工部
（２５）の面粗さは、放電加工における電極と金型素子
（２０）との間の放電ギャップを適宜変更することによ
り調整することが可能である。例えば放電ギャップを大
きくすると、面粗さは大きくなる。Further, in this embodiment, the surface roughness of the fine concavo-convex processed portion (25) can be adjusted by appropriately changing the discharge gap between the electrode and the die element (20) in the electric discharge machining. Is. For example, when the discharge gap is increased, the surface roughness increases.

【００３３】ここで、本実施形態において、金型素子
（２０）の微細凹凸加工部（２５）における面粗さ（Ｒ
max ）を１０〜２０μｍ、好ましくは１５μｍ以上に設
定するのが良い。すなわちこの面粗さが小さ過ぎる場合
には、製造される玉保持器（１０）におけるポケット内
周面での潤滑剤の保持力を十分に確保することができ
ず、潤滑剤が早期に減少して、摩擦抵抗が増大し、軸受
性能の低下を来す恐れがあり、好ましくない。逆に面粗
さが大き過ぎる場合には、製造される玉保持器（１０）
におけるポケット内周面での凹凸度合にばらつきが生じ
て、ボールとの摺動抵抗が増大して、回転トルクが増大
し、軸受性能の低下を来す恐れがあり、好ましくない。Here, in the present embodiment, the surface roughness (R) in the fine concavo-convex processed portion (25) of the die element (20).
max) is set to 10 to 20 μm, preferably 15 μm or more. That is, if the surface roughness is too small, it is not possible to sufficiently secure the retaining force of the lubricant on the inner peripheral surface of the pocket in the ball cage (10) to be manufactured, and the lubricant is reduced early. As a result, the frictional resistance increases and the bearing performance may deteriorate, which is not preferable. On the contrary, when the surface roughness is too large, the ball cage (10) manufactured
The unevenness of the inner peripheral surface of the pocket in the case is varied, the sliding resistance with the ball is increased, the rotating torque is increased, and the bearing performance may be deteriorated, which is not preferable.

【００３４】本実施形態においては、上記構成の金型素
子（２０）が上記のアキシャルドロータイプの射出成形
用金型に組み込まれる。In the present embodiment, the mold element (20) having the above structure is incorporated in the above axial draw type injection molding mold.

【００３５】そして、ポリアミド樹脂（６６ナイロ
ン）、ポリアセタール樹脂等の熱可塑性樹脂からなる成
形材料を、上記射出成形用金型のスプル、ランナー、ゲ
ートを通じてキャビティー内に注入し、固化させた後、
可動型を軸方向に移動させて型開きを行う。その後、固
定型内に残存保持された成形品としての玉保持器（１
０）を、型内に装着されたエジェクターピンにより蹴り
出すことにより取り出すものである。Then, a molding material made of a thermoplastic resin such as polyamide resin (66 nylon) or polyacetal resin is injected into the cavity through the sprue, runner and gate of the injection molding die to solidify,
The movable mold is moved in the axial direction to open the mold. After that, a ball retainer (1
0) is taken out by kicking out the ejector pin mounted in the mold.

【００３６】この樹脂成形品としての玉保持器（１０）
におけるポケット（１２）の内周面には、上記の射出成
形と同時に、金型素子（２０）の微細凹凸加工部（２
５）がそのまま転写されることにより、加工部（２５）
と同程度の面粗さ（Ｒmax ＝１０〜２０μｍ）を有する
油保持用微細凹凸部（１５）が形成される。Ball cage (10) as this resin molded product
At the same time as the above-mentioned injection molding, the inner peripheral surface of the pocket (12) of
By transferring 5) as it is, the processing part (25)
The oil-retaining fine concavo-convex portion (15) having the same surface roughness (Rmax = 10 to 20 µm) as the above is formed.

【００３７】こうして製造された玉保持器（１０）は、
上記従来例と同様に、各ポケット（１２）内にボールが
転動自在に保持された状態で内輪及び外輪間に組み付け
られて、転がり玉軸受が形成される。The ball cage (10) manufactured in this way is
Similar to the conventional example, the rolling ball bearing is formed by assembling the balls in the respective pockets (12) so as to be rollably held between the inner ring and the outer ring.

【００３８】この玉軸受においては、保持器（１０）の
ポケット内周面に微細凹凸部（１５）が形成されている
ため、その内周面における潤滑剤の保持力が増大し、ボ
ールの周囲に潤滑剤が途切れることなく供給される。こ
のため、油切れによる摩擦抵抗の増大及び早期劣化を防
止でき、安定した回転状態を長期維持することができ、
高い品質、性能を得ることができる。In this ball bearing, since the fine irregularities (15) are formed on the inner peripheral surface of the pocket of the retainer (10), the retaining force of the lubricant on the inner peripheral surface is increased, and the periphery of the ball is surrounded. The lubricant is supplied without interruption. Therefore, increase in frictional resistance due to oil shortage and early deterioration can be prevented, and a stable rotating state can be maintained for a long period of time.
High quality and performance can be obtained.

【００３９】また本実施形態の玉保持器（１０）におい
ては、放電加工により金型素子（２０）にあらかじめ微
細凹凸加工部（２５）を形成しておき、その加工部（２
５）を射出成形時に転写することにより、ポケット内周
面に微細凹凸部（１５）を形成するものであるため、微
細凹凸部（１５）の形成用としてバレル処理加工等を別
途行う必要がないので、作業工程数の増加を防止するこ
とができる。従って、簡単に製造できるとともに、生産
効率を向上できて、コストの削減を図ることができる。Further, in the ball cage (10) of the present embodiment, a fine concavo-convex processed portion (25) is previously formed on the die element (20) by electric discharge machining, and the processed portion (2
By transferring 5) during injection molding, the fine concavo-convex portion (15) is formed on the inner peripheral surface of the pocket, so that it is not necessary to separately perform barrel processing or the like for forming the fine concavo-convex portion (15). Therefore, it is possible to prevent an increase in the number of working steps. Therefore, the manufacturing can be easily performed, the production efficiency can be improved, and the cost can be reduced.

【００４０】更に本実施形態においては、高精度の加工
が可能な放電加工を用いて金型素子（２０）に微細凹凸
加工部（２５）を形成するものであるため、凹凸度合に
ばらつきが少なく、高い寸法精度の金型素子（２０）を
形成することができる。従って、この金型素子（２０）
によって成形される玉保持器（１０）のポケット内周面
を高い寸法精度に仕上げることができ、ボールを位置精
度良く安定状態に確実に保持することができ、玉保持器
（１０）、ひいては軸受製品としての品質をより一層向
上させることができる。Further, in the present embodiment, since the fine concavo-convex processed portion (25) is formed on the die element (20) by using the electric discharge machining capable of high-precision machining, there is little variation in the concavo-convex degree. A mold element (20) having high dimensional accuracy can be formed. Therefore, this mold element (20)
The inner peripheral surface of the pocket of the ball cage (10) molded by the method can be finished with high dimensional accuracy, and the ball can be reliably held in a stable state with high positional accuracy. The ball cage (10), and eventually the bearing. The quality as a product can be further improved.

【００４１】なお、上記実施形態においては、金型素子
（２０）における部分球体（２１）の外周ほぼ全域に微
細凹凸加工部（２５）を形成して、玉保持器（１０）に
おけるポケット内周面のほぼ全域に微細凹凸部（１５）
を形成するようにしているが、本発明はそれだけに限ら
れず、ポケット内周面の所要領域のみに微細凹凸部を部
分的に形成するようにしても良い。例えば部分球体（２
１）に部分的に放電加工を行って、ボールの回転周速度
の最も大きい部分、いわゆる赤道部の周辺に対応する領
域等に、部分的に微細凹凸部を形成するようにしても良
い。In the above embodiment, the fine concavo-convex portion (25) is formed on almost the entire outer circumference of the partial sphere (21) in the mold element (20), and the inner circumference of the pocket in the ball cage (10) is formed. Fine irregularities (15) on almost the entire surface
However, the present invention is not limited to this, and the fine concavo-convex portion may be partially formed only in a required region of the inner peripheral surface of the pocket. For example, a partial sphere (2
It is also possible to partially perform electric discharge machining in 1) to partially form fine irregularities in a region having the highest rotational peripheral velocity of the ball, that is, a region corresponding to the periphery of the so-called equator.

【００４２】[0042]

【発明の効果】以上のように、本発明の軸受用樹脂製玉
保持器の製造方法によれば、ポケット形成用金型素子の
外周面に、放電加工によりあらかじめ微細凹凸加工部を
形成しておき、射出成形時に、上記凹凸加工部の転写に
より、ポケット内周面に微細凹凸部を形成するものであ
るため、その微細凹凸部によってポケット内周面におけ
る潤滑剤の保持性能が向上し、軸受組付状態において、
ボールの周囲に潤滑剤を途切れなく供給することができ
る。従って、油切れによる摩擦抵抗の増大及び早期劣化
を防止できて、安定した回転状態を長期維持することが
でき、高い品質を得ることができる。またポケット内周
面の微細凹凸部を、射出成形と同時に形成するものであ
るため、微細凹凸部の形成用に別途加工する必要がな
く、作業工程数の増加を防止でき、簡単に製造できると
ともに、コストを削減することができる。更に高精度の
加工が可能な放電加工を用いて金型素子に微細凹凸加工
部を形成するものであるため、凹凸度合にばらつきが少
なく、高い寸法精度の金型素子を形成することができ
る。従って、この金型素子によって成形されるポケット
内周面を高い寸法精度に仕上げることができ、ボールを
位置精度良く安定状態に確実に保持することができ、玉
保持器としての品質をより一層向上させることができる
という効果がある。As described above, according to the method of manufacturing the resin ball cage for bearings of the present invention, the fine irregularity processed portion is previously formed on the outer peripheral surface of the pocket forming die element by electric discharge machining. Every time, during injection molding, since the fine irregularities are formed on the inner peripheral surface of the pocket by transferring the irregularity processed portion, the fine irregularities improve the lubricant retaining performance on the inner peripheral surface of the pocket. In the assembled state,
Lubricant can be supplied around the ball without interruption. Therefore, it is possible to prevent an increase in frictional resistance and early deterioration due to oil shortage, to maintain a stable rotating state for a long time, and to obtain high quality. Further, since the fine irregularities on the inner peripheral surface of the pocket are formed at the same time as the injection molding, there is no need to separately process for the formation of the fine irregularities, the increase in the number of working steps can be prevented, and the manufacturing is easy. , Can reduce the cost. Further, since the fine concavo-convex processed portion is formed on the die element by using the electric discharge machining capable of highly precise machining, it is possible to form a die element with high dimensional accuracy with little variation in the degree of concavity and convexity. Therefore, the inner peripheral surface of the pocket molded by this mold element can be finished with high dimensional accuracy, the ball can be reliably held in a stable state with high positional accuracy, and the quality as a ball cage is further improved. The effect is that it can be done.

【００４３】本発明において、金型素子の微細凹凸加工
部における面粗さを特定の範囲に設定する場合には、上
記の効果をより確実に得ることができるという利点があ
る。In the present invention, when the surface roughness of the finely textured portion of the die element is set within a specific range, there is an advantage that the above effects can be obtained more reliably.

【図面の簡単な説明】[Brief description of drawings]

【図１】この発明の実施形態の製造方法によって製造さ
れた軸受用樹脂製玉保持器を示す斜視図である。FIG. 1 is a perspective view showing a resin ball retainer for a bearing manufactured by a manufacturing method according to an embodiment of the present invention.

【図２】実施形態の玉保持器におけるポケット周辺を拡
大して示す斜視図である。FIG. 2 is an enlarged perspective view showing the vicinity of a pocket in the ball cage according to the embodiment.

【図３】実施形態の製造方法に用いられたポケット形成
用金型素子を示す斜視図である。FIG. 3 is a perspective view showing a pocket-forming mold element used in the manufacturing method of the embodiment.

【図４】従来の樹脂製冠形玉保持器が適用された軸受を
示す上側部断面図である。FIG. 4 is an upper sectional view showing a bearing to which a conventional resin crown-shaped ball cage is applied.

【図５】従来の冠形玉保持器を示す平面図である。FIG. 5 is a plan view showing a conventional crown-shaped ball cage.

【図６】従来の冠形玉保持器を示す側面断面図である。FIG. 6 is a side sectional view showing a conventional crown-shaped ball cage.

【図７】従来の冠形玉保持器におけるポケット周辺を拡
大して示す斜視図である。FIG. 7 is an enlarged perspective view showing the periphery of a pocket in a conventional crown-shaped ball cage.

【符号の説明】[Explanation of symbols]

１０…玉保持器 １１…環状体 １２…ポケット １５…油保持用微細凹凸部 ２０…ポケット形成用金型素子 ２５…微細凹凸加工部 10 ... Ball cage 11 ... Ring body 12 ... Pocket 15 ... Fine irregularities for oil retention 20 ... Mold element for pocket formation 25 ... Fine irregularity processing part

───────────────────────────────────────────────────── フロントページの続き Ｆターム(参考） 3J101 AA03 AA32 AA42 AA62 BA22 BA25 BA44 DA14 EA31 EA36 FA32    ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 3J101 AA03 AA32 AA42 AA62 BA22                       BA25 BA44 DA14 EA31 EA36                       FA32

Claims (2)

【特許請求の範囲】[Claims] 【請求項１】 環状体に、その軸方向の一方側に開口
し、かつボールを転動自在に保持する複数のポケットが
周方向に沿って設けられた樹脂製玉保持器を射出成形に
より製造する方法であって、 射出成形用金型における前記ポケットを形成するための
ポケット形成用金型素子の外周面に、放電加工によっ
て、あらかじめ微細凹凸加工部を形成しておき、 射出成形時に、前記ポケットの内周面に、前記微細凹凸
加工部の転写によって油保持用微細凹凸部を形成するこ
とを特徴とする軸受用樹脂製玉保持器の製造方法。1. A resin ball cage manufactured by injection molding, wherein a plurality of pockets, which are open to one side in the axial direction of the annular body, and which rotatably hold balls are provided along the circumferential direction. A method of forming a fine concavo-convex portion on an outer peripheral surface of a pocket-forming mold element for forming the pocket in an injection-molding die by electric discharge machining in advance. A method for manufacturing a resin ball retainer for bearings, characterized in that fine oil-holding fine irregularities are formed on the inner peripheral surface of the pocket by transferring the fine irregularities processed portion. 【請求項２】 前記ポケット形成用金型素子の微細凹凸
加工部における面粗さ（Ｒmax ）が１０〜２０μｍに設
定されてなる請求項１記載の軸受用樹脂製玉保持器の製
造方法。2. The method for producing a resin ball cage for bearing according to claim 1, wherein the surface roughness (Rmax) in the finely textured portion of the pocket forming die element is set to 10 to 20 μm.
JP2001320266A 2001-10-18 2001-10-18 Method for manufacturing resin ball retainer for bearing Pending JP2003120681A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2001320266A JP2003120681A (en) 2001-10-18 2001-10-18 Method for manufacturing resin ball retainer for bearing

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2001320266A JP2003120681A (en) 2001-10-18 2001-10-18 Method for manufacturing resin ball retainer for bearing

Publications (1)

Publication Number Publication Date
JP2003120681A true JP2003120681A (en) 2003-04-23

Family

ID=19137681

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2001320266A Pending JP2003120681A (en) 2001-10-18 2001-10-18 Method for manufacturing resin ball retainer for bearing

Country Status (1)

Country Link
JP (1) JP2003120681A (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008157310A (en) * 2006-12-21 2008-07-10 Ntn Corp Dynamic pressure bearing device and manufacturing method thereof
EP2068018A1 (en) * 2007-12-05 2009-06-10 Aktiebolaget SKF Ball bearing cage
CN102102710A (en) * 2010-12-23 2011-06-22 浙江大学 Rolling bearing retainer with micro pits
CN102494028A (en) * 2011-12-31 2012-06-13 聊城市新欣金帝保持器科技有限公司 Bearing and steel ball for processing retainer thereof
CN102979821A (en) * 2011-12-20 2013-03-20 西安奥奈特固体润滑工程学研究有限公司 Design method of single-row deep groove ball bearings
CN105626696A (en) * 2014-10-31 2016-06-01 斯凯孚公司 Bearing cage
JP2017165449A (en) * 2016-03-16 2017-09-21 東京ライト工業株式会社 cap
WO2020191517A1 (en) * 2019-03-22 2020-10-01 Schaeffler Technologies AG & Co. KG Cage for bearing and bearing

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008157310A (en) * 2006-12-21 2008-07-10 Ntn Corp Dynamic pressure bearing device and manufacturing method thereof
EP2068018A1 (en) * 2007-12-05 2009-06-10 Aktiebolaget SKF Ball bearing cage
CN102102710A (en) * 2010-12-23 2011-06-22 浙江大学 Rolling bearing retainer with micro pits
CN102979821A (en) * 2011-12-20 2013-03-20 西安奥奈特固体润滑工程学研究有限公司 Design method of single-row deep groove ball bearings
CN102494028A (en) * 2011-12-31 2012-06-13 聊城市新欣金帝保持器科技有限公司 Bearing and steel ball for processing retainer thereof
CN105626696A (en) * 2014-10-31 2016-06-01 斯凯孚公司 Bearing cage
JP2017165449A (en) * 2016-03-16 2017-09-21 東京ライト工業株式会社 cap
WO2020191517A1 (en) * 2019-03-22 2020-10-01 Schaeffler Technologies AG & Co. KG Cage for bearing and bearing

Similar Documents

Publication Publication Date Title
CN101235847B (en) Straight-line rolling slipper block and method of manufacture
CN107250582B (en) The manufacturing method of retainer for rolling bearing and rolling bearing and retainer for rolling bearing
JP6459396B2 (en) Tapered roller bearing
JP2003120681A (en) Method for manufacturing resin ball retainer for bearing
CN107110216A (en) Tapered roller bearing
WO2015141021A1 (en) Angular ball bearing
KR101371578B1 (en) Dimple-forming burnishing tool
JP6686483B2 (en) Rolling bearing cage, rolling bearing, and rolling bearing cage manufacturing method
CN107110215A (en) Tapered roller bearing
US20040037481A1 (en) Retainer with rotationally symmetric pockets
JPH02253008A (en) Ball stud for ball joint and manufacture thereof
WO2015145794A1 (en) Angular ball bearing
JP6458447B2 (en) Tapered roller bearing
JP2016145644A5 (en)
JP6686482B2 (en) Rolling bearing cage, rolling bearing, and rolling bearing cage manufacturing method
WO2016125855A1 (en) Rolling bearing retainer, rolling bearing, and method for manufacturing rolling bearing retainer
JP2003247552A (en) Manufacturing method of crown retainer for rolling ball bearing, die used for manufacturing crown retainer for rolling ball bearing, crown retainer for rolling ball bearing, and rolling ball bearing
US5666870A (en) Press die set and press machine for driving it
JP2003074561A (en) High speed rotation rolling bearing
JP2011190860A (en) Double-row cylindrical roller bearing
CN107076207A (en) Retainer and tapered roller bearing for tapered roller bearing
JP4642686B2 (en) Sliding bearing manufacturing method
JP2006161882A (en) Rolling bearing cage
JP2003120692A (en) Method of manufacturing metal ball retainer for bearing
JP3700780B2 (en) Cylindrical roller bearing

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20041014

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20070628

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20070703

A02 Decision of refusal

Free format text: JAPANESE INTERMEDIATE CODE: A02

Effective date: 20071106