Therefore, negative pressure is alternately produced in the low pressure chamber 28 and in {TAIL ~ the low pressure chamber} 35 communicating, respectively, with {HEAD ~ the pump working chambers} 14, 14 
Therefore , negative pressure is alternately produced in the low pressure chamber 28 and in { TAIL ~ the low pressure chamber } 35 communicating , respectively , with { HEAD ~ the pump working chambers } 14 , 14
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH