An aspirator may comprise an aspirator body defining an air channel, an aspirator inlet disposed in the aspirator body whereby the air channel receives a compressed fluid, a venting aperture disposed in the aspirator body in fluid communication with the air channel, and a venting valve disposed in the venting aperture. The venting valve is in an open position and the venting valve moves to a closed position in response to the compressed fluid being received by the aspirator.

An aspirator may comprise an aspirator body defining an air channel, an aspirator inlet disposed in the aspirator body whereby the air channel receives a compressed fluid, a venting aperture disposed in the aspirator body in fluid communication with the air channel, and a venting valve disposed in the venting aperture. The venting valve is in an open position and the venting valve moves to a closed position in response to the compressed fluid being received by the aspirator.

A spool valve includes a valve portion that opens and closes a portion between an input port and an output port and a radial-direction-position changing portion provided in an outer lateral surface of the valve portion in a radial direction. When a first value is equivalent to or larger than a threshold that is larger than 0, the portion between the input port and the output port are opened to permit a flow of the oil inside the first connection oil passage, and when the first value is smaller than the threshold, the portion is closed to block the flow of the oil inside the first connection oil passage. The radial-direction-position changing portion extends in the axial direction, and a position thereof in the radial direction changes inwardly from a first side towards a second side in the axial direction.

An apparatus for dosing a fluid flow system with treatment fluid/chemicals is described. The apparatus includes a vessel; an inlet pipe or hose and an outlet pipe for coupling to the system so that fluid from the system may flow into the vessel and return into the system to flush chemicals from within the vessel and into the system. The vessel has a piston within it and the vessel wall defines a cylinder in which the piston moves under pressure of incoming fluid from a first position at which the vessel contains fluid to be dispensed into the system to a second position corresponding to substantially complete emptying of the vessel. The piston has a bypass passage through or around it that opens when the piston substantially reaches the second position so that fluid from the system may flow passed the piston when the piston is at the second position.

This system (1) for mixing a chemical product with water comprises a water inlet port (3) designed to be connected to a pipe for supplying water under pressure, a chemical product inlet port (5) designed to be connected to a chemical product reservoir (100), and a mixture outlet port (7). It comprises a main chamber (11) in which is movable a piston (13) delimiting an upstream part (15) of the main chamber (11) that is fluidly connected to the water inlet port (3) and a downstream part (19) of the main chamber (11) that is connected to the chemical product inlet port (5), wherein the piston (13) is provided with a rod (130) extending in the downstream part (19) of the main chamber (11). The water inlet port (3) is also connected to the mixture outlet port (7), wherein the downstream part (19) of the main chamber (11) is also connected to the mixture outlet port (7). A water flow rate regulating device (60) is interposed between the upstream part (15) of the main chamber (11) and the water inlet port (3). The piston (13) is movable in the main chamber (11) under the action of the water entering the upstream part (15) of the main chamber (11) and the pressure difference created by the rod (130) of the piston (13) in the downstream part (19) of the main chamber (11), so that the chemical product contained in the downstream part (19) of the main chamber (11) is directed towards the mixture outlet port (7).

Apparatus for dispensing a dose of fluid, the apparatus comprising a dispensing vessel with a dispensing outlet, the vessel having a piston and a vessel wall defining a cylinder in which the piston may move under pressure from a first position to a second position, wherein the apparatus has a bypass passage that extends through the first piston and has a valve member that is opened by a valve actuating plunger in the piston that moves within the piston to push the valve open when the valve actuating plunger abuts a shoulder at or near the second position in the vessel; wherein the shoulder at the second position is an annular shoulder and the apparatus is adapted to dispense fluid in a sequence of stages comprising a mixing stage and a dispensing stage.

A spool valve includes a valve portion that opens and closes a portion between an input port and an output port and a radial-direction-position changing portion provided in an outer lateral surface of the valve portion in a radial direction. When a first value is equivalent to or larger than a threshold that is larger than 0, the portion between the input port and the output port are opened to permit a flow of the oil inside the first connection oil passage, and when the first value is smaller than the threshold, the portion is closed to block the flow of the oil inside the first connection oil passage. The radial-direction-position changing portion extends in the axial direction, and a position thereof in the radial direction changes inwardly from a first side towards a second side in the axial direction.

This system (1) for mixing a chemical product with water comprises a water inlet port (3) designed to be connected to a pipe for supplying water under pressure, a chemical product inlet port (5) designed to be connected to a chemical product reservoir (100), and a mixture outlet port (7). It comprises a main chamber (11) in which is movable a piston (13) delimiting an upstream part (15) of the main chamber (11) that is fluidly connected to the water inlet port (3) and a downstream part (19) of the main chamber (11) that is connected to the chemical product inlet port (5), wherein the piston (13) is provided with a rod (130) extending in the downstream part (19) of the main chamber (11). The water inlet port (3) is also connected to the mixture outlet port (7), wherein the downstream part (19) of the main chamber (11) is also connected to the mixture outlet port (7). A water flow rate regulating device (60) is interposed between the upstream part (15) of the main chamber (11) and the water inlet port (3). The piston (13) is movable in the main chamber (11) under the action of the water entering the upstream part (15) of the main chamber (11) and the pressure difference created by the rod (130) of the piston (13) in the downstream part (19) of the main chamber (11), so that the chemical product contained in the downstream part (19) of the main chamber (11) is directed towards the mixture outlet port (7).

An apparatus for dosing a fluid flow system with treatment fluid/chemicals is described. The apparatus includes a vessel; an inlet pipe or hose and an outlet pipe for coupling to the system so that fluid from the system may flow into the vessel and return into the system to flush chemicals from within the vessel and into the system. The vessel has a piston within it and the vessel wall defines a cylinder in which the piston moves under pressure of incoming fluid from a first position at which the vessel contains fluid to be dispensed into the system to a second position corresponding to substantially complete emptying of the vessel. The piston has a bypass passage through or around it that opens when the piston substantially reaches the second position so that fluid from the system may flow passed the piston when the piston is at the second position.