초록 ▼

A fluid system for calibrating a variable area metering valve during flight when the fluid receiver is not in operation employs several single point fixed calibration orifices that are sequentially used to establish a corresponding number of calibration points in a short time interval. The position

A fluid system for calibrating a variable area metering valve during flight when the fluid receiver is not in operation employs several single point fixed calibration orifices that are sequentially used to establish a corresponding number of calibration points in a short time interval. The position of the metering valve movable element is stored in a memory of a microprocessor for each calibration point and the metering valve may thereafter be driven by the microprocessor to control with precision flow rates to the receiver without the need for a flow meter. Operation is free to bench calibration inaccuracies and possible drift due to mechanical wear.

대표청구항 ▼

A method of providing an in-flight accurate fluid flow rate calibration curve for a metering system comprising: providing pressurized fluid for utilization by a receiver through conduits including a first shut-off valve that is intermittently operated during flight and a variable area metering valve

A method of providing an in-flight accurate fluid flow rate calibration curve for a metering system comprising: providing pressurized fluid for utilization by a receiver through conduits including a first shut-off valve that is intermittently operated during flight and a variable area metering valve; providing a plurality of fixed calibration orifices, each with a pressure drop sensor and calibrated at a particular, different set point such that for a given pressure drop across the orifice the flow rate through that orifice is precisely known; supplying said pressurized fluid through said variable area metering valve to a selected one of said fixed calibration orifices in sequence during flight while said first shut-off valve is closed; and recording the precise position of said variable area metering valve in the memory correlated with the known flow rates associated with each of said calibration orifices for subsequent retrieval and use during flight for controlling said variable area metering valve to regulate the flow rate to said receiver.