RACEWAY SURFACE MANUFACTURING METHOD OF THRUST TYPE BALL BEARING

• Main Authors: NARUMIYA HIROKI, HIRAGAMI DAISUKE, FUJITA TAKASHI
• Format: Patent
• Language: English; Japanese
• Published: 15.03.2018
• Subjects: BEARINGS; BLASTING; CHEMISTRY; ELEMENTS OR CRANKSHAFT MECHANISMS; ENGINEERING ELEMENTS AND UNITS; FLEXIBLE SHAFTS; FORGE FURNACES; FORGING; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HAMMERING; HEATING; LIGHTING; MAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES,RIVETS, BOLTS OR WHEELS; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; MECHANICAL ENGINEERING; MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVINGMATERIAL; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; PERFORMING OPERATIONS; PRESSING METAL; PUNCHING METAL; RIVETING; ROTARY BODIES OTHER THAN GEARING ELEMENTS; SHAFTS; THERMAL INSULATION IN GENERAL; TRANSPORTING; WEAPONS

PROBLEM TO BE SOLVED: To provide a raceway surface manufacturing method of a thrust type ball bearing, capable of forming a compressed hydrostatic pressure stress field near a surface of a rolling groove in forging, reducing a cavity around an inclusion existing near the surface of the rolling groove bottom, and reducing a cavity around the inclusion near a rolling raceway surface in a short time.SOLUTION: An annular workpiece with austenite as a main phase is used. In order that a heating temperature T1 (°C) in forging and a press-in amount D (mm)of a mold with an annular convex shape satisfy a specific relation, by pushing the mold against the workpiece, a rolling groove is formed. Next, tissues of the workpiece formed with the rolling groove is defined as tissues of a martensite main body.SELECTED DRAWING: Figure 5 【課題】鍛造時に転動溝の表面近傍に圧縮の静水圧応力場を形成し、転動溝底の表面近傍に存在する介在物周りの空隙を減少させ、短時間で転動軌道表面近傍の介在物周りの空隙を減少させる、スラスト型玉軸受の軌道面作製方法を提示すること。【解決手段】オーステナイトを主相とする円環状のワークを用いる。鍛造時の加熱温度Ｔ１（℃）と円環状の凸型を有する金型の押し込み量Ｄ（ｍｍ）とが特定の関係を満足するように、ワークに対して前記金型を押し付けることにより、転動溝を形成する。次いで、上記転動溝が形成されたワークの組織をマルテンサイト主体の組織とする。【選択図】図５