Patent ID: 6551082
Filing Date: 2003-04-22
Classification: F04C

Abstract:
An oil-free type screw compressor comprising:a low pressure stage compressor main body and a high pressure stage compressor main body each having a cooling jacket for the cooling by oil; a first passage for supplying the lubrication oil to a bearing and/or a timing gear in each compressor main body; a second passage for supplying the lubrication oil to each cooling jacket for cooling the compressor main body; an oil sump for accommodating the lubrication oil which has passed through the first or second passage; and an oil cooler capable of cooling the lubrication oil to two different temperatures, wherein the lubrication oil passing through the first passage is introduced into the oil sump without passing through the second passage, and wherein the lubrication oil with the lower-temperature is introduced to the second passage, and the lubrication oil with the higher-temperature is introduced to the first passage.