| 摘要 |
971,651. Rotary pumps. J. B. CASTLE Jun., E. W. CARSON, and R. A. RICHARDSON. Nov. 1, 1961 [June 12, 1961], No. 39071/61. Heading F1F. A variable displacement rotary sliding vane pump comprises a rotor 31, Fig. 2, keyed to a driven shaft 33 and formed with a plurality of radial slots 41 slidably mounting vanes 47 urged outwardly by centrifugal force and pump discharge pressure into engagement with the inner surface of a pump cylinder 55 which also comprises the inner race of a roller bearing 51, whose outer race 53 snugly fits the bore of a pivot ring 15. The pivot ring 15 has a lug 17 pivotedly mounted on a pin 19 to permit adjustment of pump capacity and also reversal of flow without reversing the driven shaft 33. Two such pump units, adjustable independently of each other, are mounted in a cylindrical pump housing 1, Fig. 1, having a partition 9 and flanked by end housings 81, each of which is formed with diametrically opposite suction (or discharge) ports 95. The position of the ring 15 and hence which of the ports 95 is a supply port and which a discharge port depends on the supply of pressure fluid to one or other of cylinders 161 slidably mounting spring-loaded pistons 163. Each end housing 81 houses a porting rotor 61 keyed to the shaft 33, a spacer 111, a balance plate 115 and a port plate 101. The porting rotors 61, spacers 111 and balance plates 115 together with the two rotors 31 and a spacer 35 therebetween are clamped between a shaft shoulder 117 and a nut 123 to rotate together whilst the port plates 101 of slightly less thickness than the spacers 111 is each secured to its stationary end housing 81. Each port plate 101 is formed on either face with an arcuate recess 103, Fig. 3, extending over the flared end of associated port 95 and ports 105 interconnecting the recesses 103 and each connected by a radial port 107 with the flared end. Each port of a ring of ports 63 in a porting rotor 61 is associated with a flow channel 43 located between adjacent vanes on the proximate face of a rotor 31 and co-operates with the adjacent recess 103 and its associated ports 105, 107 to pump the liquid between the diametral ports 95. An annular space 144, Fig. 6, between each spacer 111 and port plate 101 connects via a passage 147 and a passage 149 fitted with a shuttle ball valve 153, the inner ends of the slots 41 to that port 95 functioning as a pump discharge port. Roller bearings 69 similar to the roller bearings 51 surrounding the rotors 31 surround the porting rotors 61. In a modification, not shown, the roller bearings 51 are replaced by a ring of bearing metal such as brass or bronze which is hydraulically balanced by applying pump pressure about the outer surface thereof. |
