PURPOSE: To improve the volume efficiency by making through-holes through respective driven screws then communicating the suction side end and the delivery side end through intermediate splitted section and fitting the opposite end sections of respective driven screws retractably to a bottomed bush.
CONSTITUTION: Through-holes 15 are made through respective driven screws 6 to communicate between the suction and delivery side ends 12, 10 through intermediate split section 18 while the delivery and suction side end sections 10, 12 of respective driven screws 6 are fitted retractably to the bottomed bushes through rotation of screw assembly is the intermediate pressure Pm between the delivery pressure Pd at the delivery port 3 and the suction pressure Ps at the suction port 2 at the intermediate split section 18 of driven screw 6 and said intermediate pressure Pm will function through the through-hole 15 to the opposite ends of driven screw shaft section 6' thus to achieve load balance in axial direction of the shaft section 6'. As a result, shrinkage of driven screw shaft 6 is halved when compared with conventional one while the gap for avoiding interference between the drive screw shaft 5 and the driven screw shaft 6 can be set low resulting in improvement of pump volume efficiency.
| WO/2020/109553 | SCREW PUMP FOR COOLING BATTERY PACKS |
| JP2016114045 | SCREW PUMP |
| JPH0518369 | COIL TYPE SCREW PUMP |
CHIKUHICHI HITOSHI
HIROOKA YASUO
