An improved control over the pressure vented or tapped to {HEAD ~ a back pressure chamber} in {TAIL ~ a scroll compressor} is achieved by maintaining a vent hole closed for the majority of the operational cycle of the scroll compressor 
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An improved control over the pressure vented or tapped to { HEAD ~ a back pressure chamber } in { TAIL ~ a scroll compressor } is achieved by maintaining a vent hole closed for the majority of the operational cycle of the scroll compressor
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH