SE322128B - - Google Patents

Abstract

1,061,278. Rotary pumps. JABSCO PUMP CO. Oct. 23, 1964 [June 26, 1964], No.43353/64. Heading F1F. A rotary cam vane pump comprises a housing 12, Fig. 1, mounted on a suitable pedestal 14 and having a body portion 16 with a cylindrical chamber 20 open at one end and a closure portion 18, a single-lobed cam 32 having end walls (42), (44), Fig. 2 (not shown) and a peripheral wall (46) secured to a rotary shaft 26 and circumferentially-spaced flexible vanes 52, carried by and extending the whole width of the housing which sealingly engaging the cam. Liquid enters the pump through an axial passage 76 in the closure portion 18 and an axial opening 62 in the cam which spirals radially outwardly and opens into the increasing volume intervene spaces and is discharged from the decreasing volume intervane spaces through a port 80 formed in a radially extending flange 48 of the cam 32 having sealing engagement with the closure portion 18 by means of labyrinth seals 78, 86. The port 80 is located radially outwards of the peripheral wall 46 of the cam and discharges into an annular chamber 82 surrounding the axial inlet passage 76. The cam instead of being singlelobed may have any number of lobes with a corresponding number of pumping cycles for every revolution of the cam. The outwardly radial spiral provides centrifugal pumping action, ensures that the increasing volume intervane spaces are filled under pressure and prevents cavitation. In a modified embodiment, the flexible vanes (152), Fig. 6 (not shown) are formed on an elastomeric annulus (154) which is bonded to a tubular portion (116). The tubular portion in this instance is held between two end portions for easy replacement when the vanes become worn. One of the end portions closing the end of the chamber and supporting the shaft and the other including the pump inlet and pump outlet. In another embodiment, (not shown), fluid is admitted to and discharged from both ends of the chamber.