Patent ID: 7114913
Filing Date: 2006-10-03
Classification: F04B,F04C

Abstract:
1. A lubricant-cooled gas compressor ( 11 ) adapted to discharge a mixture of lubricant and compressed gas and provided with means ( 13 ) for separating the lubricant downstream of the compressor ( 11 ) and with a return line ( 16 ) for returning the separated lubricant to the compressor ( 11 ), characterized in that the return line ( 16 ) is controlled by a restrictor valve ( 22 ) which is mechanically operated by a thermostat ( 37 , 38 ) immersed in lubricant in the return line ( 16 ), the arrangement being such that the return flow of lubricant to the compressor ( 11 ) is restricted when the temperature of the lubricant falls and is increased when the temperature of the lubricant rises; the compressor ( 11 ) characterized in that the restrictor valve ( 22 ) comprises a housing ( 30 ) having a lubricant inlet ( 32 ) and a lubricant outlet ( 33 ), the outlet communicating with an annular chamber ( 34 ) within the housing ( 30 ) which is coaxial with, intermediate the ends of and of greater diameter than a bore ( 31 ) within the housing communicating with the inlet ( 32 ), a sleeve ( 35 ) moveable axially of the bore ( 31 ) whereby an opening ( 36 , 36 A) in the wall of the sleeve ( 35 ) may be brought into or out of register with the chamber ( 34 ) and the thermostat is a thermostatic device ( 37 , 38 ) within the bore ( 3 l) which will respond to changes in the temperature of lubricant passing through the housing ( 30 ) thereby to displace the sleeve ( 35 ) to vary the area of said opening ( 36 , 36 A) which is exposed to the chamber ( 34 ).