GB820648A - Improvements in or relating to rotary pumps of the outwardly-sliding vane type - Google Patents

Abstract

820,648. Rotary pumps. DESCHAMPS, D. J. Nov. 22, 1956 [Nov. 29, 1955], No. 35801/56. Class 110 (2). In a variable-capacity multiple pump unit of the outwardly-sliding vane type wherein the vanes are disposed radially or in planes parallel to radii, the central rotor is equal in width to the combined widths of the end rotors and the central stator 76 is spring-biased about a common pivot 90 in a direction opposite to that of the end stators 66, 86 thereabout. The stator 76 is rigidly mounted on the pivot 90 whilst the stators 66, 86 are mounted thereon with a small degree of angular play. The outlet port of the central pump is offset 180 degrees from the outlet ports 67 of the end pumps and the vanes 115 of the central rotor are offset relative to the vanes of the end rotors which are in phase with one another. Fuel is discharged from the pump through passages 96, 97, 98 in the pivot 90 and thence to an outlet port 37, part of the fuel being fed through a chamber 91, a filter and an adjustable pressure-reducing valve (see Fig. 11, not shown), to the shaft bearings 41, 42. The capacity of the pump is varied by a valve 160 which is adapted to control the supply of pressure fluid from a conduit 173 to an outlet conduit 191 communicating with a piston-andcylinder unit, see Fig. 6 (not shown), and is adapted to unload said unit through passages 192, 184, 178, 201, as desired, the passage 201 communicating with the inlet side of the pump. The piston varies the eccentricity of the pumps by acting on a shaft 100 which has a limited rotation in any one direction of 45 degrees and is geared to a ported sleeve 180 surrounding the valve 160. The sleeve has a limited rotation of 60 degrees in either direction and the relative movement between the sleeve and shaft 100 automatically permits re-setting of the valve to the desired position necessitated by leakage in the system. Leakage along the valve 160 is recirculated to the inlet side of the pump through conduits 193, 201. Reference has been directed by the Comptroller to Specification 743,088.