GB1096402A - Improvements in or relating to rotary pumps - Google Patents

Abstract

1,096,402. Rotary pumps. G. A. FAIRBAIRN. March 3, 1965 [March 9, 1964], No. 9129/65. Heading F1F. A rotary positive displacement pump comprises a rotary plate 14, Fig. 1, which is formed with a peripheral slot and geared to a transversely disposed disc 4 carrying a helical-shaped piston 6 which is a close running fit in an annular chamber 1. The piston which passes in timed relation through the slot is housed with side and peripheral clearance in its housing 13 so that any highpressure liquid leaking from the annular chamber through a slot 15 interconnecting the annular chamber and the housing 13 has equal access to both sides of the plate to maintain the same pressure on both sides to obviate distortion of the plate and reduce friction between the plate and its housing. Liquid enters the pump through an inlet 8 and passes into an annular inlet chamber 25 connected by an inlet port 10, Fig. 2, with the annular chamber 1 and is discharged through an outlet port 11. To reduce "water hammer" the disc 4 may carry diametrically opposite pistons which co-operate with two diametrically opposite slots in the plate 14. The effects of "water hammer" may be further reduced by providing the disc 4 with three equally spaced pistons and providing two plates 14 each with three slots with separate inlet and outlet ports for each plate 14.