| 摘要 |
966,875. Rotary pumps. A. PETIT & CIE S.a.r.L. March 20, 1961 [April 7, 1960; Nov. 24, 1960], No. 10031/61. Heading F1F. The output of a rotary positive displacement pump 17 controlled by permitting fluid to leak across an end face of the rotor or rotors. A rotary pump, such as a gear pump or a pump with a gyratory piston (Figs. 3 and 4, not shown) has a plate 12 urged towards the end faces of the rotors 5, 6 by pressurized fluid which has leaked into the enclosed chamber 11, and by the spring-loaded pistons 19. The pressure in chamber 11 may be controlled by connecting it to atmosphere, or to the pump inlet through a pipe 20 and valve 21. Fig. 5 shows a tank 43 mounted directly on the pump Liquid enters the tank at 44 and passes through a tube 45 to the pump inlet 28. The pump output is reduced or stopped by an actuating valve 48, thus relieving the pressure in the chamber 11. This is done by turning a cam 51 which presses on an arm 53, or by a float 49 falling (should the liquid level fall). A valve 54 in the pump outlet positively stops the flow when the output pressure is sufficiently low. |
