Method and control device for dosing flow media
AssigneePierburg Luftfahrtgerate Union GmbH
InventorsHeinz Holzem, Helmut Kehrmann
Life of this patent
Estimating the term…
Abstract
A method and system for providing dosing of fluid is described. The method and system is directed to the control of a plurality of parallel on/off valves which regulate the flow of the fluid. The system includes a plurality of base control valves for delivering a base flow amount. The base control valves are preferably arranged to have binary graduation of their respective flow rates. These base control valves are optionally discontinuously switched on and/or off for delivering the base flow amount. A "timed" valve is varied according to pulse-width modulation techniques to deliver a continuously variable partial flow. The control of the timed valve is effected by electrical circuitry which generates a feedback error signal related to the flow quantity.
Claims14
A flow control system for the control of a plurality of parallel-connected on/off valves comprising:
- a plurality of base control on/off valves connected in parallel between the input and output lines of a flowing medium, said valves subject to on/off control by an electrical signal;
- means for providing control signals for controlling said base control valves, said means responsive to a nominal input control signal;
- a timed valve subject to control by a pulse-width modulated signal, said valve connected parallel to the base control valves between said input and output lines;
- means for providing signals which are analogs of the values of flow through each of the valves;
- summing means for combining said flow-analogous signals to form a signal representing the actual flow through the output line;
- means for comparing the actual flow signal with said nominal input control signal to form an error signal;
- and
- means responsive to said error signal for pulse-width modulating said timed valve.
Dependencies are inferred from the claim text.