Simplified capacity control mechanisms for scroll compressors include a fork operable to open and close vents associated with a pair of scroll compression chambers. A single fork opens and closes both vents simultaneously. In the past, separate members have been utilized to open and close the two individual...http://www.google.fr/patents/US5947701?utm_source=gb-gplus-shareBrevet US5947701 - Simplified scroll compressor modulation control
