a variable throttle mechanism installed in said pump to change a flow rate of {HEAD ~ said discharged oil} from said pump to {TAIL ~ said hydraulic device} 
to
a variable throttle mechanism installed in said pump to change a flow rate of { HEAD ~ said discharged oil } from said pump to { TAIL ~ said hydraulic device }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL