GB1295473A - - Google Patents

Abstract

1295473 Rotary hydraulic machines. G E E WARDER 18 Feb 1970 [26 Feb 1969] 10227/69 Heading F1F A rotary hydraulic pump or motor comprises a pair of cylindrical relatively rotable disc components having coplanar faces, one component being formed with an annular working chamber to and from which hydraulic fluid is led and a plurality of radial slots crossing the annular chamber in each of which is slidably mounted a vane having a recess or gateway, the coplanar face of the other component closing the annular chamber and having axially projecting therefrom into the annular chamber at least one abutment, inlet and outlet ports in said other components and means for radially moving the vanes during relative rotation of the components, wherein the gateways allow each vane in turn to pass the abutment or abutments and at least two of the vanes at all times are positioned across the chamber to enclose between them a volume of fluid so that the pressure difference between inlet and outlet pressure is sub-divided into at least two stages. Described as a pump, a first disc component constituting a rotor includes outer and inner concentric members 1,2 Fig.1 secured together and forming therebetween an annular chamber 3 and a second disc component constituting a stator includes outer and inner concentric members 27, 28 having coplanar faces co-operable with end faces of the rotor members 1,2 and with the end face of a part 6 secured to the rotor. The member 27 is formed with a cam groove 44 which co-operates with ears 33 formed on vanes 7 to 22, Fig.3, radially slidable in slots 5 which cross the annular chamber 3. Between the members 27, 28, diametral bores 35, 36 house spring-loaded abutments 24, 25 and the member 28 on opposite sides of each abutment is provided with inlet and outlet ducts 47, 48, which open respectively into arcuate inlet and outlet ports 45, 46. The cam groove 44 is sinusoidal and is such that when the vanes are moved to their radial outermost positions a gateway 34 in each vane permits the vane to pass an abutment and when moved to their radial innermost positions they cross the annular chamber to sub-divide the chamber. At any one time at least two vanes 19, 20, left side of Fig.3 and 10,11,12 right side of Fig.3, cross the chamber to trap fluid therebetween in spaces D to provide improved sealing between the suction spaces R and the discharge spaces P. The annular chamber also houses a control sleeve 23 which under the action of a control pressure urges the sleeve axially and with it the abutments 24, 25 to vary the volume of the working chamber and hence pump output. A fluid space 62 surrounding the vanes is connected to a fluid space 63 to equalize the pressure acting upon opposite ends of the vanes. An annular recess 60 in the rotor member 1 collects control fluid leakage from behind the sleeve and returns it to the inlet side of the pump. Passages 54 through the sleeve allow it to move freely. There may be two or more concentric annular chambers co-operating with further abutments and vane gateways to provide further pumping chambers. Capillary tubes may be included in the control pressure lines to damp oscillations of the sleeve 23. In an alternative embodiment, the annular chamber may be formed in the stator which is also formed with the slots carrying the vanes whilst the abutments are carried by the rotor.