| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a constitution wherein theoretical values on the premise of adiabatic compression are used in combination with the operation efficiency of a compressor in detecting an abnormal rise in actual discharge temperature. <P>SOLUTION: The refrigerant circuit 1 includes temperature sensors S1, S2 and a pressure sensor S3 for discharge paths 11a, 11b of the compressors 1a, 1b and a temperature sensor S12 and a pressure sensor S5 for an intake path 12 thereof. In this circuit, a control part 10 is provided that calculates the maximal refrigerant discharge temperatures TD1<SB POS="POST">t</SB>, TD2<SB POS="POST">t</SB>in normal operation based on the detected pressures PH of a discharge path 11, the detected pressure PL and detected temperature TS2 of the intake path 12, and the operation efficiency of the compressors 1a, 1b, determines whether the detected refrigerant discharge temperatures TD1, TD2 of the discharge path 11 are equal to high refrigerant discharge temperatures TD1<SB POS="POST">r</SB>, TD2<SB POS="POST">r</SB>higher than the maximal refrigerant discharge temperatures TD1<SB POS="POST">t</SB>, TD2<SB POS="POST">t</SB>in normal operation by at least a predetermined value, and detects the abnormality of the compressors 1a, 1b so long as they are equal to the high refrigerant discharge temperatures TD1<SB POS="POST">r</SB>, TD2<SB POS="POST">r</SB>higher by at least the predetermined value. <P>COPYRIGHT: (C)2012,JPO&INPIT</p> |
