The present invention provides a quick startup device for a centrifugal pump. The device includes an upper self-priming chamber, a lower self-priming chamber, and an inlet pipe sequentially arranged from top to bottom. The upper self-priming chamber and the lower self-priming chamber are integrally mounted on the inlet pipe. A main shaft and a hexagonal partition member rotatably mounted on the main shaft are arranged on an axis of the upper self-priming chamber. A blade tip of each partition plate is closely attached to an inner wall surface of the upper self-priming chamber. Three identical accommodation grooves are provided on an inner side of the upper self-priming chamber. A spring and a separation baffle are arranged in each accommodation groove, an exhaust hole is provided on one side of each accommodation groove, and an air intake pipe is provided on the other side of each accommodation groove.

The present invention provides a quick startup device for a centrifugal pump. The device includes an upper self-priming chamber, a lower self-priming chamber, and an inlet pipe sequentially arranged from top to bottom. The upper self-priming chamber and the lower self-priming chamber are integrally mounted on the inlet pipe. A main shaft and a hexagonal partition member rotatably mounted on the main shaft are arranged on an axis of the upper self-priming chamber. A blade tip of each partition plate is closely attached to an inner wall surface of the upper self-priming chamber. Three identical accommodation grooves are provided on an inner side of the upper self-priming chamber. A spring and a separation baffle are arranged in each accommodation groove, an exhaust hole is provided on one side of each accommodation groove, and an air intake pipe is provided on the other side of each accommodation groove.

A pump is formed by a housing (10) having an inlet (11) for connection to a source of fluid and an outlet (12) for pumped fluid. A rotor (15) is rotatable within the housing and the inlet (11) and the outlet (12) are spaced apart around the path of the rotor (15) in the housing. The rotor (15) has surfaces (16a, 16b, 16c, 16d) that form, with the housing (10), closed chambers (18a, 18b, 18c, 18d) which travel around the housing (10) to convey fluid from the inlet (11) to the outlet (12). The housing (10) carries a seal (14) that is located between the inlet (11) and the outlet (12) in the direction of travel of the rotor (15). The seal (14) co-operates with the rotor surfaces (16a, 16b, 16c, 16d) as the surfaces (16a, 16b, 16c, 16d) pass between the outlet (12) and the inlet (11) to prevent the formation of a chamber during said passage and so prevent fluid flow from the outlet (12) to the inlet (11). Such a pump is easily and cheaply produced and is particularly useful in medical applications.

A hydraulic pump is described comprising a rotor provided for rotation about a longitudinal axis (X-X) within a housing. The pump comprises a plurality of chambers for pumping a fluid that are provided by longitudinally extending recesses in a circumferential outer surface of the rotor. During use the recesses are moved across a circumferential inner surface of the housing, and in so doing, are moved over an inlet port in the housing to draw fluid into the chamber and then over an outlet port in the housing to discharge the fluid. The hydraulic pump further comprises a roller that is mounted in a longitudinally extending pocket of the housing. The roller is positioned after the outlet port in a direction of the rotor's rotation and is arranged to follow the outer surface of the rotor and seal against each recess as it is drawn past the roller, thereby directing fluid from the chamber into the outlet port.

A pump is formed by a housing (10) having a fluid inlet (11) and a fluid outlet (12) and containing a rotor (15) forming with the housing (10) chambers (17a, 17b) that, on rotation of the rotor (15) by a drive, convey fluid from the inlet (11) to the outlet (12) to pump the fluid. A seal assembly (14) is arranged between the outlet (12) and the inlet (11). The seal assembly (14) includes a membrane (21) that contacts the rotor (15) and a flexible resilient spring member (22, 28, 35, 37, 40) that provides a force urging the membrane (21) against the rotor (15). The spring member (22, 28, 35, 37, 40) thus, on rotation of the rotor (15), moves radially relative to the axis of rotation of the rotor (15) and is arranged to provide a force on the rotor (15) via the membrane (21) that is constant and a minimum to maintain a seal between the rotor (15) and the seal (14) for a given outlet pressure of the pumped fluid.

A concentric rotary fluid machine includes a first body and a second body that are rotatable relative to each other and coaxially arranged one inside the other. A plurality of gates are supported by the second body in gate pockets. Each gate pocket includes: a gate retention recess that receives a gate cylinder of a gate; a gate seal recess that receives a sealing portion of a gate; and an intervening land. The sealing portion is configured to reciprocate up and down within a corresponding gate seal recess while maintaining contact with the recess and the second body. A plurality of lobes on the first body cause the gates to swing about respective swing axes as the first body rotates relative to the second body. The lobes and the lands are configured so that a lobe forms a substantial seal against a land when in mutual radial alignment.

A hydraulic pump is described comprising a rotor provided for rotation about a longitudinal axis (X-X) within a housing. The pump comprises a plurality of chambers for pumping a fluid that are provided by longitudinally extending recesses in a circumferential outer surface of the rotor. During use the recesses are moved across a circumferential inner surface of the housing, and in so doing, are moved over an inlet port in the housing to draw fluid into the chamber and then over an outlet port in the housing to discharge the fluid. The hydraulic pump further comprises a roller that is mounted in a longitudinally extending pocket of the housing. The roller is positioned after the outlet port in a direction of the rotor's rotation and is arranged to follow the outer surface of the rotor and seal against each recess as it is drawn past the roller, thereby directing fluid from the chamber into the outlet port.