Abstract: A fuel pump for a fuel system includes a nozzle, a venturi, a pump inlet and a flow controller. The nozzle has an orifice through which fuel is ejected and the venturi is downstream of the nozzle and has an inlet through which fuel discharged from the orifice flows, a passage downstream of the venturi inlet through which fuel flows to create a drop in pressure in the area of the venturi, and an outlet through which fuel is discharged from the venturi. Fuel is drawn through the pump inlet by the drop in the pressure created in the area of the venturi and the flow controller is downstream of the outlet and has a chamber in which fuel from the venturi outlet is received. The flow controller causes fuel to fill the venturi to ensure performance of the fuel pump.

Abstract: A dry roughing vacuum pump includes a valve (10; 15) with a through-passage arranged in the discharge line (9), the valve (10) with a through-passage being able to move between a closed position in which the valve (10; 15) with a through-passage is in contact with a seat of a mouth (12) of the discharge line (9) and an open position in which the valve with a through-passage is moved away from the mouth (12) of the discharge line (9), the vacuum pump including a motor gas injection device (13) that is configured to inject a motor gas into the inlet (11a) of the Venturi-effect passage (11).

Abstract: The present invention discloses a venturi pumping arrangement which is used to pump fluids or solutions with a high efficiency. The arrangement comprises an inner pipe and an outer pipe having a passage therebetween. The inner pipe is partially located in the venturi shaped profile of the outer pipe. A chamber has an inlet through which a fluid is passed under pressure which in turn passes through the passage which produces a reduced pressure within the outer pipe which causes a second fluid to be drawn through the inner pipe into the outer pipe. The clearance of the passage is able to be varied on the arrangement to provide variable load performance.

Abstract: A vacuum producing device comprises a venturi unit which functions to produce or stop producing a vacuum after predetermined movement of a surrounding sleeve and air shut off member and includes silencing means for substantially reducing the sound of pressure air passing through the device.

Abstract: A nozzle having a through passageway in which the flow of pressurized fluid induces the flow of secondary fluid therethrough with the passageway having a throat that is adjustable in cross-sectional extent to enable the nozzle to efficiently operate over a wide range of operating conditions. The throat extent may be automatically changed with a change in the operating condition within its range or as in one embodiment be easily set for one operating condition.