GB661772A - Improvements in or relating to high pressure liquid pumps - Google Patents

Abstract

661,772. Gear-wheelpumps. BORGWARNER CORPORATION. March 18, 1949. [March 26, 1948] No. 7432/49. Class 110(ii). To secure effective sealing in a gear pump without excessive friction, the combined high pressures on the areas A2, A<SP>3</SP> of a bush 16, slightly exceed the average, opposite pressure within the pumping chamber 12 plus the high pressure acting on the cut-away surface A<SP>4</SP>. The area of the latter surface is preferably obtained by the cut and try method. Pressure fluid passes to it by way of a groove 16c or an oblique channel cut through the bush, Fig. 4 (not shown). Light springs S give initial loading on the bushes 16 but the force exerted is small compared with the fluid pressure on the bushes. A passage 20 allows pressure fluid to flow to a chamber outside the bushes 16. A through passage 15c allows pressures to be balanced axially on the lower bushes 16, 17. An area A<SP>7</SP>, equal to an area A<SP>5</SP>, communicates with the high pressure side. A seal assembly 25 comprises a splined coupling 25a, flange 25b, bearing washer 25c and flexible ring 25d. In an alternative arrangement, Fig. 5, the splined drive is in the plane of the gear 114 and high-pressure fluid acts at both ends of the pump and on surfaces 117a. The axial grooves and spline passage allow adequate lubrication of the shaft journals. U.S.A. Specification 2,420,622 is referred to.