METHOD FOR CONTROLLING DISCHARGE TEMPERATURE IN OIL COOLED DISPLACEMENT TYPE ROTARY COMPRESSOR

摘要

PURPOSE:To enable proper control of lubricant temperature by setting a set temperature according to discharge dew-point, in a rotary compressor a three- way valve distributing in which/collected oil of lubricant contained in compressed gasto an oil cooling unit or a bypass pipe is controlled according to the temperature. CONSTITUTION:A compressor main body 1 compresses and discharges, mixed medium consisting of gas and oil and lubricant in the mixed medium is separated and collected by an oil collector 2 on the way. The collected oil is introduced to the suction side of an oil pump 7 through a pipe f passing through an oil cooling unit 3 or a pipe g bypassing the oil cooling unit 3 by a three-way valve 4 to circulate the lubricant again. The three-way valve 4 detects the discharge temperature of the mixed medium and controls the temperature by a temperature adjusting meter 5 for adjusting distribution ratio to pipes f, g. In this case, set temperature of the temperature adjusting meter 5 is set based on the discharge dew-point computed by an arithmetic unit 9 from output of a suction pressure detector 8, suction temperature detector 11 and a suction humidity detector 10.