US4313465A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and control device for dosing flow media
Assignee: Pierburg Luftfahrtgerate Union GmbH
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Filing: 1978-11-09
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Granted: 1982-02-02
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Expires: 1998-11-09
Abstract
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.
Inventors
- 👤 Heinz Holzem
- 👤 Helmut Kehrmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 11:26
CPC Classifications
G; G05; G05D; G05D7/00; G05D7/06; G05D7/0617; G05D7/0629; G05D7/0635; G05D7/0641; G05D7/0652; G05B; G05B11/00; G05B11/01; G05B11/14; G05B11/18; Y; Y10; Y10T; Y10T137/00; Y10T137/8593; Y10T137/87265; Y10T137/87298; Y10T137/87306; Y10T137/87314
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
158 words
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.
Claim 2
Dependent Claim
158 words
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.
Claim 3
Dependent Claim
11 words
The system of claim 1 wherein said valves are solenoid valves.
Claim 4
Dependent Claim
29 words
The system of claim 2 including a plurality of switches for switching the flow-analogous signals, said switches controlled by answer signals developed by current flow through said solenoid valves.
Claim 5
Dependent Claim
41 words
The system of claim 1 wherein said means for providing control signals for controlling said base control valves is an A/D converter, said converter providing a plurality of digital control signals for controlling said base control valves in a binary-coded manner.
Claim 6
Dependent Claim
63 words
The system of claim 4 including means for compensating switching hysteresis in said A/D converter and the tolerances in the calibration of the other valves and wherein the maximum flow of said pulse width-modulated valve is selected so that the amount of compensation of said compensating means and the smallest base flow amount is within the linear range of said pulse-width modulated valve.
Claim 7
Dependent Claim
27 words
The system of claim 4 including means for providing emergency operation when one or several valves fail by timing said base control valves which are still effective.
Claim 8
Dependent Claim
73 words
The system of claim 6 wherein said pulse-width modulating means includes an integrating regulator and means for providing a "dead zone" which is responsive to the output of the integrating regulator and coupled to the A/D converter input, said "dead zone" means uncoupling the regulator during normal operation but permitting coupling to said A/D converter input during emergency operation to effect a free oscillation about one of the switching points of said converter.
Claim 9
Dependent Claim
31 words
The system of claim 7 including means to reduce the integrating speed of said regulator during emergency operation so that a sufficiently large minimum pulse width results for adjusting free oscillations.
Claim 10
Dependent Claim
16 words
The system of claim 1 including means for maintaining constant the pressure difference above said valves.
Claim 11
Dependent Claim
14 words
The system of claim 1 wherein said pulse-width modulating means includes an integrating regulator.
Claim 12
Dependent Claim
28 words
The system of claim 10 wherein said pulse-width modulating means includes a clock frequency generator and a comparator responsive to said clock frequency generator and said integrating regulator.
Claim 13
Dependent Claim
38 words
The system of claim 1 including means for eliminating those modulation ranges of the pulse-width modulated valve in which there is a lack of linearity between the flow and the average of the control pulse per unit time.
Claim 14
Dependent Claim
28 words
A system in accordance with claim 1 including a plurality of switches for switching the flow-analogous signals, said switches controlled by valve answer signals provided by hydraulic means.
Claim 15
Dependent Claim
25 words
A system according to claim 1 including a tracer for use with each valve to determine whether or not there is flow through the valve.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-02-01 | 1985-08-03 | 1986-02-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-02-01 | 1989-08-03 | 1990-02-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-02-01 | 1993-08-03 | 1994-02-02 | $7700.00 | Window Closed / Lapsed |