JPS643321A - Oil impregnated metal powder sintered bearing - Google Patents

Abstract

PURPOSE:To reduce noise shortly after the use of bearing as well as to improve conformability by specifying the copper content to be a ratio by weight of a specified range, and specifying the opening area of pores in the sliding surface to be a ratio of a specified range to the whole sliding surface in oil impregnated metal powder sintered bearing of a copper-steel family. CONSTITUTION:In an oil impregnated metal power sintered bearing wherein copper and steel are main compounds, the copper content is made to be 8-90wt.%, and the opening area of pores in the sliding surface is made to be 0.1-10% of the whole sliding surface. This constitution thereby allows the bearing to comprise a two phase structure consisting of a flexible copper-rich phase and a steel-rich phase. In addition, the narrowing of pore opening area enables the quantity of lubricant returned to the bearing against the quantity of lubricant leached from the sliding surface to be relatively reduced. This constitution thereby can prevent lubricant from being in need wherein lubricant leached from the pores in the sliding surface goes into the pores again, can also reduce noise shortly after the use of the bearing, and enables the time required until the coefficient of friction will be stabilized to be shortened, thereby enabling conformability to be improved.