Abstract: A sliding member of an iron-based non-porous material, such as vane, of a rotary compressor has a sliding surface processed by a surface treatment in which the surface is subjected to oxidizing and nitriding to form an oxidized and nitrided layer thereon. The surface is then subjected to a steam-treatment in which water is caused to react with components of the oxidized and nitrided layer to form a layer of oxidized iron of a porous network structure disposed outwardly of the oxidized and nitrided layer. The oxidized iron layer is composed mainly of tri-iron tetroxide and softer than the oxidized and nitrided layer.

Abstract: A hermetic rotary compressor has a motor unit composed of a stator and a rotor which are arranged in an upper portion of a hermetic housing, an oil-lubricated compressor unit arranged in a lower portion of the hermetic housing, a crank shaft which interconnects said motor unit and said compressor unit, a discharging silencer which is formed by a lower bearing of the compressor unit positioned around the lower end of the crank shaft and a cover of the lower bearing. The hermetic rotary compressor further has a lower balancing weight mounted around a lower shaft end portion of the crank shaft which extends to a position below the discharging silencer and a weight cup surrounding the lower balancing weight. In this hermetic rotary compressor, the lower balancing weight is not disposed within the discharging silencer.