Patent ID: 7181954
Filing Date: 2007-02-27
Classification: F25B,F25D

Abstract:
1. A refrigerant leak detector of a compressor, comprising: a compressor that compresses and supplies a flammable refrigerant to a refrigeration cycle of a refrigerator; a brushless DC motor that drives the compressor; a switching circuit that supplies drive signals to the brushless motor; control means that PWM-controls the switching circuit; direct-current power supplying means that supplies drive-use direct current power to the switching circuit; duty measuring means that measures the duty value of a PWM signal in the control means; drive value measuring means that measures drive values including voltage, current and power relating to the direct-current power supplied by the direct-current power supplying means; duty determining means that determines whether or not the duty value measured by the duty measuring means exceeds a duty variation width where the duty value measured at a duty measurement reference time is used as a reference; drive value determining means that determines whether or not a time rate-of-change per unit time of the drive value measured at the drive value measurement reference time by the drive value measuring means exceeds a drive value reference rate-of-change; and refrigerant leak determining means which determines that the flammable refrigerant is leaking when it is determined in the duty determining means that the duty variation width has been exceeded and it is determined in the drive value determining means that the drive value reference rate-of-change has not been exceeded or which determines that the flammable refrigerant is not leaking when it is determined in the duty determining means that the duty variation width has been exceeded and it is determined in the drive value determining means that the drive value reference rate-of-change has been exceeded.