GB572967A - Improvements in gear-wheel pumps - Google Patents

Abstract

572,967. Gear wheel pumps or motors. PUMP ENGINEERING SERVICE CORPORATION. Aug. 19, 1943, No. 13530. Convention date, April 15, 1942. [Class 110 (ii)] In a gear pump or motor end sealing plates 38 on the bearing bushes are subjected to the high-pressure fluid on the outside and a relieving pressure in each space 46, on the inside. These pressures may act on one end of each gear only. Duplicated, valve-controlled ports, allow the relevant pressures to function, when the driving shaft 74 (for a pump) is reversed. Bearing bushes 32 have flat portions, 38a, Fig. 5, and sealing plugs 38c. The housing 11 and end closure plates 17 are of lightweight material, such as aluminium and the bushes of bronze. Sealing rings 39 are provided. The bushes, and plates 38, have limited axial play between high and low pressure areas. Fig. 8 shows fluid from the pressure conduit 49, of the pump, forcing down valve 52 and entering a space 41, but if the pump drive is reversed, valve 52 closes, and valve 52a opens. The space 46 communicates with the low pressure conduit 48 by way of either valve 57 or 57a. A passage 61 connects the two low pressure regions. Springs 63 press on washers 62 to give initial pressure between the gear faces and the bush flanges. Passages 66, 71, through the gears allow low-pressure fluid to pass to the inner face of a flexible coupling 68. Splines 73 are forced on an extension 72 of the gear journal 34 to engage with splines on a shaft 74 which has a flange 75 engaging a bearing ring 76. The latter presses against a flexible ring 77. A compression spring 80 is provided. The recess 46 may be cut in the gear instead of in the bush, and may vary in shape. The pump delivery pressure may vary from 1,000 to 5,000 lb. per square inch, or even exceed 5,000 lb. per square inch.