GB1224265A - Improvements in and relating to a rotary, positive-displacement pump - Google Patents

Abstract

1,224,265. Rotary positive-displacement pumps. REX CHAINBELT Inc. July 30, 1969 [Oct. 31, 1968], No.38257/69. Heading F1F. Pumping is effected by a rotor 20 with outwardlysliding vanes 22 engaging with a non-rotary ring 23 whose eccentricity can be changed automatically by pistons 91, 91a to control the output. Pressureloaded plates 40, 41 furnished with pairs of suction and discharge ports have layers of bearing material e.g. bronze, abutting the rotor and the ring 23, a ring 90 preventing excessive force being applied to the ring 23 by said plates. A pin 92 opposes radial thrust exerted on the ring 23 by the working fluid between the vanes. The piston 91 is loaded by pressure transmitted thereto from an area bounded by pressure-loaded sealing-rings in a groove 66<SP>1</SP> surrounding the suction ports in the plate 41. The piston 91a is loaded by a spring 111 and pressure transmitted thereto from a pressureloading area bounded by pressure-loaded sealing- rings in a groove 66<SP>1</SP> surrounding the discharge ports in the plate 41. The pressure applied to the piston 91a is regulated by spring-loaded valvespool 114 in response to the output pressure of the pump. The ports in the plate 41 communicate with identical ports 47, 57 in the plate 40 through the spaces between the vanes, the latter ports being connected to respective passages 82, 140 for the working fluid. Pressure-equalizing grooves 48, 58 in each of the plates are connected to the corresponding ports. A single "shot" of working fluid for lubricating purposes is fed from the grooves 48 to each of bearings 27, 28 per revolution of the rotor by way of radial slots 151, 151a in the rotor and similar slots in the plates. The pin 92 may be replaced by a rockable thrust-block, Figs. 9 and 10 (not shown).