Patent GB-341874-A (GB)
Title: An improved fluid pressure pump or turbine
IPC: F04C11/00
Filed: 1929-10-21
Abstract: 341,874. Rotary pumps. WARREN, R., 9, Fauconberg Road, Sutton Court, Chiswick, London. Oct. 21, 1929, No. 31976. [Classes 110 (i) and 110 (ii).] Fixed-abutment type.-A rotary impeller of the outwardly-sliding vane type is combined in series or in parallel with a centrifugal impeller. The former impeller pumps fluid through a bypass to secure priming for the centrifugal stage of the pump. An impeller B, Figs. 1 and 2, has outwardly-sliding vanes K which pump fluid entering a port e<1>, and which is forced centrifugally through passages H, to a delivery port f<1> and volute G. The vanes may be forced out centrifugally, by springs or by fluid under pressure. A liner F which is secured by a screw N is thicker on one side than on the other and may be turned slightly when worn and secured by the screw N in one of the grooves n<1>. Grooves M, M<1> which are formed on either side of the driving shaft b<1> and communicate with the suction side and pressure side of the impeller respectively, allow fluid being pumped to circulate through a groove m<2> around the shaft b<1> for cooling and lubricating purposes. Instead of grooves, separate pipes M, M<1> may be used. The pump shaft b<1> may be reversed, or a liner carrying the inlet port D and the delivery f<1> may be made rotatable through 180 degrees to reverse the direction of flow of fluid through the pump without reversing the direction of rotation of the shaft. A perforated liner which rotates with the impeller may be provided. A spring-loaded disc bears against one side of the impeller to compensate for wear of the latter. The blades may be guided by pins, which move in circumferential slots in the above disc. In a modified arrangement a piston blocks the inlet port except for small holes in its head, when the impeller is started up, but suction in the pump lifts the piston to open the inlet port. The piston has straight or spiral guides. In a further alternative a flap valve is provided to shut off part of the pumping space until the impeller is running at speed when the suction produced, opens the valve. A modified arrangement embodies a cone-piece which leads part of the fluid entering the pump to the pumping space but allows a quantity of fluid to pass directly to the delivery. In Fig. 12 the impeller has two passages H the front passage being reduced in diameter. The piston T under the action of a spring t<2> shuts off the rear passage H but allows the fluid entering at E to pass outwards and through a conduit t<4> to force back the piston T and so open the rear passage to the incoming fluid. A bore hole t<5> allows a quantity of fluid to pass through the piston T to the delivery side of the pump. In another modification the interior of the inlet pipe D is provided with a cylindrical member closed at one end and provided internally with curved blades which are acted upon by a backward flow of fluid to cause the said member to rotate and slide against a seating arranged in the inlet pipe, thus preventing fluid in the pump from returning through the inlet pipe. A forward flow of the fluid due to rotation of the impeller causes the member to rotate and slide off its seating and allow fluid to flow in through perforations in the periphery of the member which perforated surface acts as a strainer. Fig. 14 shows two impellers in series, the outer one B being of the form shown in Fig. 1 and the inner impeller W being an ordinary centrifugal impeller. Fluid is pumped from an inlet D through the impeller B and then by way of the impeller W delivered to a volute G. Cooling and lubricating grooves M, m<2> are provided. In a modification the centrifugal impeller chamber is cut off by a flap valve until the impeller B has discharged fluid to the outlet G when the suction of the latter lifts the flap valve and both impellers operate in parallel. The functions of the pump may be reversed and fluid admitted at the periphery of the impeller used to drive the latter as a rotary engine.