Review on Plain Bearing Researches in Japan for Half a Century (Part 1): Statically Loaded Bearings

摘要

I intend to look back at the study of sliding bearings in Japan for the last 50 years, mainly on the basis of articles published by the Japanese Society of Mechanical Engineering and by other scientific societies. Sixty years have now passed since the end of the Second World War in 1945. In Japan, the reconstruction began with the introduction of technology from the advanced countries of Europe and the United States. Independent development efforts and economic growth followed. Generally speaking, the main objectives of mechanical engineering in the first half of the past 50 years were to increase performance and enhance power. During the second half of the period, some new concerns were added: environmental protection, reduced energy consumption, and conservation of resources. Bearings are elements of machinery. They exist without being installed into machine tools, but are important elements that determine the performance and reliability limits of machines. Consequently, bearings contribute to the progress of machine-building technology and to progress in general. According to the above-mentioned objectives, progress has been achieved in every aspect of the study of sliding bearings: analysis, structure, design, materials, production, and maintenance. For example, in the aspect of analysis, former assumptions in respect to infinite width, isothermal condition, isoviscosity, and rigidity were proved to be wrong. Studies aimed to increase both velocity of operation and capacity began with the appearance of computers and are continuing by means of numerical analyses under conditions very close to the implementation. In 1955, Hirano [1] published an article entitled "Lubrication of Bearings" that described the development of sliding bearings in connection with 11 items and presented many important references to foreign authors. However, the problems considered in this publication were limited to static conditions. Subsequently, dynamic problems began to appear in the field of sliding bearings as machines became bigger, began to function at faster operational speeds, and provided better performance.