[KSCI] Korea Science Citation Index Service

A Study on Hydrodynamic Coefficient Characteristics of Air Bearing for High Speed Journal

Lee, Jong-Ryul (Engineering Research Institute, Gyeongsang National University)
Lee, Deug-Woo (Department of Precision Mechanical Engineering, Pusan National University)
Soeng, Sueng-Hak (Department of Precision Mechanical Engineering, Pusan National University)
Lee, Yong-Chul (Department of Precision Mechanics, Yonam Institute of Digital Technology)

Publication Information

KSTLE International Journal / v.4, no.2, 2003 , pp. 66-72 More about this Journal

Abstract

This paper presents the hydrodynamic effect by the journal speed, eccentricity and source positions in order to overcome the defects of air bearing such as low stiffness and damping coefficient. Choosing the two row source position of air bearing is different from existing investigations in the side of pressure distribution of air film because of the high speed of journal and the wedge effects by the eccentricity. These optimal choices of the two row source positions enable us to improve the performance of the film reaction force and loading force as making the high-speed spindle. In this paper, The pressure behavior in theory of air film in high speed region of journal according to the eccentricity of journal and the source positions analyzed. The theoretical analysis has been identified by experiments. The results of investigated characteristics may be applied to precision devices like ultra-precision grinding machine and ultra high-speed milling.

Keywords

Hydrodynamic effect; two row source positions; wedge effects; film reaction force; loading force;

Citations & Related Records

Reference

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