A multistage aspirator for an inflatable assembly may comprise a first end defining a primary gas inlet and a second end defining a gas outlet. An internal surface of the multistage aspirator may define a flow path extending from the primary gas inlet to the gas outlet. A first stage of the multistage aspirator may include a first stage orifice extending from the internal surface to an external surface of the multistage aspirator. A second stage of the multistage aspirator may include a second stage orifice located downstream of the first stage orifice and extending from the external surface to the internal surface.

A multistage aspirator for an inflatable assembly may comprise a first end defining a primary gas inlet and a second end defining a gas outlet. An internal surface of the multistage aspirator may define a flow path extending from the primary gas inlet to the gas outlet. A first stage of the multistage aspirator may include a first stage orifice extending from the internal surface to an external surface of the multistage aspirator. A second stage of the multistage aspirator may include a second stage orifice located downstream of the first stage orifice and extending from the external surface to the internal surface.

A vacuum generation system includes a main ejector having a first fluid inlet and a second fluid inlet. The second fluid inlet is configured and adapted to pull dissolved gases out of fuel. The system includes a plurality of fluid sources configured and adapted to be variably supplied to the first fluid inlet of the main ejector. A method of modulating pressure in an ejector to generate a vacuum includes supplying a fluid to an ejector from at least one of a plurality of fluid sources, and generating a vacuum with the ejector for removing dissolved gasses out of fuel.

Check valve inserts define a valve seat for an open position of a check valve and have an outer support seatable in an internal chamber of the check valve and have an inner annular ring spaced radially inward from the outer support by a rib that angles axially toward a central longitudinal axis to position an upper surface of the inner annular ring a distance axially beyond an upper surface of the outer support. Check valves have a housing defining an inlet port, an outlet port, and a chamber in fluid communication with the inlet and outlet ports, have the check valve insert seated with the chamber, and have a seal disc moveable within the chamber between the open position defined by the inner annular ring of the check valve insert and a closed position. The seal disc is translatable in response to a pressure difference across the seal disc.

A convergent nozzle is in a flow path from a liquid inlet of the ejector and a liquid outlet of the ejector. A convergent end of the convergent nozzle has a smaller cross-sectional area than an inlet of the convergent nozzle. The convergent nozzle is sized to increase a velocity of the liquid to supersonic velocities and decrease a pressure of the liquid. A low pressure housing includes a low pressure inlet into an interior of the low pressure housing. A convergent-divergent nozzle includes a mixed liquid inlet in fluid communication to receive fluid from the convergent nozzle and the low pressure housing.

A convergent nozzle is in a flow path from a liquid inlet of the ejector and a liquid outlet of the ejector. A convergent end of the convergent nozzle has a smaller cross-sectional area than an inlet of the convergent nozzle. The convergent nozzle is sized to increase a velocity of the liquid to supersonic velocities and decrease a pressure of the liquid. A low pressure housing includes a low pressure inlet into an interior of the low pressure housing. A convergent-divergent nozzle includes a mixed liquid inlet in fluid communication to receive fluid from the convergent nozzle and the low pressure housing.

A quick-release vacuum pump which is mainly applied to a vacuum transport system. The vacuum pump has a mechanism in which part of compressed air supplied for generating a vacuum state is stored firstly in a chamber, and then the vacuum state within the chamber is released when transportation is completed. When the vacuum state is released, a check valve is moved by the pressure of air that flows backward. The range of movement of the check valve is adjusted by a control means. An air filter is disposed at the lower end of the check valve. The release of the vacuum state is quick and controllable. Also, the filter is naturally filtered and cleaned.

A quick-release vacuum pump which is mainly applied to a vacuum transport system. The vacuum pump has a mechanism in which part of compressed air supplied for generating a vacuum state is stored firstly in a chamber, and then the vacuum state within the chamber is released when transportation is completed. When the vacuum state is released, a check valve is moved by the pressure of air that flows backward. The range of movement of the check valve is adjusted by a control means. An air filter is disposed at the lower end of the check valve. The release of the vacuum state is quick and controllable. Also, the filter is naturally filtered and cleaned.

A multistage vacuum includes a tank and a vacuum generating head mounted on the tank. The vacuum generating head includes a housing having multiple chambers and a gang of parallel multistage ejectors, where the respective stages of each ejector share a common chamber.

A multistage vacuum includes a tank and a vacuum generating head mounted on the tank. The vacuum generating head includes a housing having multiple chambers and a gang of parallel multistage ejectors, where the respective stages of each ejector share a common chamber.