A high pressure metering valve has a valve element with a closing portion, a metering portion and a rapid return portion.
There is provided a metering valve (10) for assembly with a pressurised dispensing container (not shown).
A control unit (10) adjusts a metering valve (7) in dependence on the mass flow rate or the pressure of the gas in order to adjust the ratio as necessary to maintain its value constant.
The gas sample is taken from the sampling gas source (13) through a metering valve (12) with a metering loop (16) at low pressure and passed, together with the carrier gas at higher pressure, into the flow divider.
The connection pipe (9) has a water-metering valve (10) that provides sufficient pressure for the water to be distributed towards the liquidizing compartment or jug (3).
A controller (k) is connected to the first electromagnetic proportioning valve group, the second electromagnetic proportioning valve group, and the third electromagnetic proportioning valve group.
The proportioning valve is adapted to control the flow of hot air through the conduits.
A proportional valve (308) may be mounted externally to the manifold or the proportional valve mount may be integrated into the manifold.
The present invention further includes a closed loop control system utilizing measurement of the density of the output mixture to control the activation of the proportioning valve.
The top of the supporting means incorporates, suitably fixed thereto, at least one reservoir (8) with a metering cap (9) for the necessary cleaning fluids.