Patent ID: 6393852
Filing Date: 2002-05-28
Classification: A47F,F04C,F25B,G05D,Y02B

Abstract:
A refrigeration compressor control system, comprising:a compressor that is selectively operable while energized in at least two states, including a first state corresponding to a first capacity and a second state corresponding to a second capacity lower than said first capacity; a load sensor for sensing a property indicative of demand for cooling; and a controller coupled to said load sensor for producing a variable duty cycle control signal in which the duty cycle is a function of demand for cooling, said controller including a module for establishing a variable cycle time for said variable duty cycle control signal, wherein said cycle time varies as a function of fluctuations in the pressure of the compressed refrigerant, said controller being coupled to said compressor for causing said compressor to selectively alternate between said first and second states in response to said variable duty cycle control signal, thereby adjusting the capacity of said compressor to the demand for cooling while said compressor is energized.