Patent ID: 7387498
Filing Date: 2008-06-17
Classification: F04B,F04C

Abstract:
1. A method for attenuating noise in at least one heating or cooling system, comprising: providing at least two compressors selectably controlling the rotational speed and the phase of operation of each compressor of the at least two compressors; sensing outlet pressure pulses associated with each compressor of the at least two compressors; determining the rotational speed and the phase of operation of each compressor of the at least two compressors based on the sensed outlet pressure pulses; controlling the rotational speed of the at least two compressors at a predetermined rotational speed that is substantially the same for each compressor of the at least two compressors; and shifting the phase of operation of at least one compressor of the at least two compressors so that outlet pressure pulses operatively produced by the at least two compressors are substantially evenly spaced.