GB1145681A - Improvements in or relating to rotary pumps and rotary motors - Google Patents

Abstract

1,145,681. Rotary pumps and motors. G.A. FAIRBAIRN. June 3, 1966 [March 3, 1965; Aug.3, 1965], Nos. 5574/66 and 33047/65. Heading F1F. A rotary pump or motor, described as a liquid pump, comprises a casing 10, Fig. 2, having an annular chamber 11 in which rotates a plurality of equispaced piston elements, two, 13a, 13b shown, carried by a rotor 12 mounted on a shaft 18 driven, e. g., from the power take-off shaft of an agricultural tractor. A valve disc (or discs) 14 having a plurality of apertures equal in number to the number of piston elements is mounted on a shaft 23, Fig.4 disposed at right angles to the shaft 18 and driven at the same speed as that shaft through skew gears 21, 22 so that the piston elements pass in timed relation through the apertures. Water entering the casing 10 through an axial inlet passage (19), Fig. 3 (not shown) passes between spokes 12b of the rotor 12 and through an inlet port 15 into the annular chamber 11 and leaves the annular chamber through a port 16 on the other side of the disc 14. The periphery of the disc 14 rotates in an annular pocket 28 both larger in width and diameter than the disc so that water admitted to the pocket from the inlet side of the pump through an opening 28a acts on both sides of the disc to eliminate deformation of the disc and reduce friction between it and the casing. The port 16 is tangentially disposed with respect to the annular chamber 11 to provide smooth flow and the piston elements are disposed so that at least one is between the inlet port 15 and the port 16 to prevent back flow. When there is more than one valve disc, each disc includes an associated inlet port and outlet port disposed one on either side of the disc at its position of intersection with the annular chamber. The number of piston elements however is greater than the number of inlet ports and the number of outlet ports.