Hybrid dosing unit

摘要

An assembly provides a proportioned gas flow and includes
a device that provides a pressurized flow of said gas,a release unit that releases the proportioned gas flow, anda chamber having an inlet fluidically connected to the device and an outlet fluidically connected to the release unit. The assembly further includesan admission valve inserted between the inlet of the chamber and the device,a metering valve inserted between the outlet of the chamber and the release unit, anda computer programmed to control the admission valve and the metering valve to provide a proportioned gas flow to the release unit.

The assembly further comprises a calibrated orifice inserted between the outlet of the chamber and the release unit.

主权项

1. An assembly to provide a proportioned gas flow, the assembly comprising:
a device that provides a pressurized flow of gas; a release unit that releases the proportioned gas flow; a chamber having an inlet fluidically connected to the device and an outlet fluidically connected to the release unit; an admission valve inserted between the inlet of the chamber and the device; a metering valve inserted between the outlet of the chamber and the release unit; a computer programmed to control the admission valve and the metering valve so as to provide a proportioned gas flow to the release unit; a calibrated orifice inserted between the outlet of the chamber and the release unit; and wherein the computer is programmed to control the admission valve and the metering valve according to a set gas flow rate value:
wherein for a set flow rate value greater than a first predetermined limit, the computer is programmed to apply at least one sonic metering step wherein the admission valve and the metering valve are open for a determined period simultaneously, at a determined frequency;wherein for a set flow rate value less than a second predetermined limit, the computer is programmed to apply at a determined frequency, at least:a step for filling the chamber, wherein the admission valve is open and the metering valve is closed; anda volumetric metering step, wherein the admission valve is closed and the metering valve is open for a determined period.