HighPerformance Ball Bearings for Automotive （高效能的汽车的滚珠轴承）.pdfVIP

High-performance Ball Bearings for Automotive Alternator Applications Kenji Ohkuma and Masao Koshigaya Ball Bearing Technology Department, Bearing Technology Center ABSTRACT This report describes the latest ball bearing technology for automotive alternators. Since compact alternators appeared on the auto market, the ball bearings used in them have presented difficulties. These difficulties have been overcome by technical breakthroughs such as a new theory about the process for ball bearing flaking and the development of a special grease with a unique ability to prolong bearing life dramatically by easing shock and vibration. Additionally, NSK Super- NBR contact seals have been created to take the place of polyacrylic rubber seals used at approximately 140°C. Other advances in technology for bearing components have also been achieved. An unwavering commitment to the continuous improvement of alternator bearings will enable NSK to remain a leader in the industry. 1. Introduction 2. Environment of Alternator Bearings Bearings for automotive alternators, which are exposed With engine performance becoming higher and to external and worn-brush dust particles and muddy alternators getting smaller, the running speed of water, while being operated at high and low speeds under alternators that formerly ranged from a maximum of high temperatures and high loads, are required to satisfy 15 000 to 18 000 rpm is now required, in certain cases, to rigid performance requirements, as well as be highly achieve a level in excess of 20 000 rpm. Installation of air reliable. Particularly, the operating conditions of small conditioning and ABS increases the installation density in fan-type alternators, which have been mass-produced for the engine space, and thereby contributes to rises