Patent US5351059A successfully refreshed from Google Patents.
US3681983A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for measuring fluid flow
Assignee: Individual
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Filing: 1971-05-11
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Granted: 1972-08-08
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Expires: 1991-05-11
Abstract
Abstract A system for measuring fluid flow, and more specifically, a speedometer/odometer system for a sailboat or the like, includes a transducer mounted to tilt at an angle by fluid flowing there around. The transducer contains an elongated arcuate cavity with an electrically resistive element extending along the bottom of the cavity. As the angular tilt of the transducer is varied by varying fluid flow, a drop of mercury moves along the cavity making electrical contact with various points of the resistive element to vary the electrical resistance value of the transducer. An operational amplifier receives a signal from the transducer via a first summing resistor and passes the signal to a meter for providing a visual indication of the velocity of fluid flow or the speed of the boat. A second summing resistor of lesser value may be switched to the operational amplifier to provide an increased signal for an expanded scale of the meter to sense small incremental changes of the boat''s speed. A third summing resistor connects the operational amplifier to a potentiometer for generating an adjustable input signal to center the meter for the expanded scale readings. An integrating amplifier receives the signal from the transducer for advancing an odometer indicator in steps or increments such that a motor driving the odometer indicator will conserve power from the voltage source which may be small batteries.
Inventors
- 👤 William Alexander
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:52
CPC Classifications
G; G01; G01P; G01P5/00; G01P5/02; G01P5/04
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
83 words
A sysTem for measuring fluid flow comprising a tiltably mounted transducer and a metering circuit electrically coupled to the transducer, said transducer having an elongated arcuate cavity therein, an electrically resistive element disposed along the bottom of said cavity and electrically connected to said metering circuit, and a mass of electrically conductive material free to move within said cavity in electrical contact with said resistive element for varying the electrical resistance of said transducer in response to an angular tilt of the transducer.
Claim 2
Independent Claim
83 words
A sysTem for measuring fluid flow comprising a tiltably mounted transducer and a metering circuit electrically coupled to the transducer, said transducer having an elongated arcuate cavity therein, an electrically resistive element disposed along the bottom of said cavity and electrically connected to said metering circuit, and a mass of electrically conductive material free to move within said cavity in electrical contact with said resistive element for varying the electrical resistance of said transducer in response to an angular tilt of the transducer.
Claim 3
Dependent Claim
69 words
A system for measuring fluid flow in accordance with claim 1 wherein said resistive element comprises a pair of parallel resistive strips extending longitudinally along the bottom of said cavity, and wherein said mass of electrically conductive material comprises a mass of mercury in contact with both of said resistive strips for making an electrical contact there between at a positioning determined by the angular tilt of said transducer.
Claim 4
Dependent Claim
38 words
A system for measuring fluid flow in accordance with claim 1 further comprising a pivotal mounting for said transducer, said transducer being operable to be pivoted by the flow of the fluid to create said angle of tilt.
Claim 5
Dependent Claim
51 words
A system for measuring fluid flow in accordance with claim 3 wherein said system constitutes a speedometer for a boat, said system comprising a bracket attached to the boat and extending downwardly therefrom, said pivot point being situated at the lower end of said bracket whereon said transducer is pivotally mounted.
Claim 6
Dependent Claim
87 words
A system for measuring fluid flow in accordance with claim 2 wherein said system constitutes a speedometer for a boat, said system comprising an electrical cable having electrical conductors connected between said resistive strips of the transducer and said metering circuit, said electrical cable being mechanically attached at one end to said transducer and adapted to be fastened at the other end to said boat, said cable being operable to suspend said transducer downwardly from said boat whereby said transducer may provide said angular tilt while suspended.
Claim 7
Dependent Claim
28 words
A system in accordance with claim 5 and further comprising a rudder vane extending rearwardly from said transducer for orienting said transducer with respect to the fluid flow.
Claim 8
Dependent Claim
67 words
A system for measuring fluid flow in accordance with claim 1 wherein said metering circuit comprises an operational amplifier having a plurality of input summing means, and a meter responsively coupled to said operational amplifier for providing an indication of velocity of said fluid flow, at least one of said summing means being electrically coupled to said transducer for passing signals from said transducer to said amplifier.
Claim 9
Dependent Claim
105 words
A system for measuring fluid flow in accordance with claim 1 wherein said system constitutes a speedometer for a boat, said system comprising an operational amplifier having an input summing junction and having an output terminal, an input summing resistor coupled between said transducer and said summing junction of the operational amplifier, a feedback resistor coupled between said output terminal and said summing junction of the operational amplifier, and a meter coupled to said output terminal of the operational amplifier for providing a visual indication of the speed of said boat derived from a signal from said transducer which is passed by said operational amplifier.
Claim 10
Dependent Claim
136 words
A system in accordance with claim 8 comprising two summing resistors both electrically coupled to said transducer, and a switch coupled between said summing resistors and said summing junction of the operational amplifier for coupling a selected one of said summing resistors to said summing junction, a first of said summing resistors being substantially equal in resistive value to the resistive value of said feedback resistor and being operable to pass a signal to said operational amplifier corresponding directly to the speed of said boat, the second of said summing resistors being substantially less in reSistive value than the resistive value of said feedback resistor for passing a substantially greater signal to said operational amplifier to provide an expanded scale reading on said meter whereby incremental changes in the speed of said boat may be determined.
Claim 11
Dependent Claim
58 words
A system in accordance with claim 9 comprising an adjustable signal source, and a third summing resistor coupled between said adjustable signal source and said switch, said adjustable signal source being operable to provide a meter centering adjustment when said second summing resistor is switched to said summing junction to provide the expanded scale reading for said meter.
Claim 12
Dependent Claim
40 words
A system in accordance with claim 8 comprising an adjustable voltage source for compensating said system for deterioration of battery power, and a further summing resistor coupled between said adjustable voltage source and said summing junction of the operational amplifier.
Claim 13
Dependent Claim
160 words
A system for measuring fluid flow in accordance with claim 1 wherein said system constitutes an odometer for a boat, said system comprising an integrating amplifier electrically coupled to said transducer, said amplifier having an input summing junction and an output terminal, a capacitor coupled between said output terminal and said summing junction of the integrating amplifier for accumulating charge and gradually increasing a signal level appearing at said output terminal of the integrating amplifier, a signal level detecting means coupled to said output terminal of the integrating amplifier, an odometer indicator, means responsively coupled to said signal level detecting means and controllably coupled to said odometer indicator for incrementally advancing said odometer indicator when the signal level of said output terminal of the integrating amplifier reaches a predetermined value, and means responsively coupled to said signal level detecting means for discharging said capacitor when the signal level of said output terminal of the integrating amplifier reaches said predetermined value.
Claim 14
Dependent Claim
98 words
A system in accordance with claim 12 wherein said signal level detecting means comprises a first NOR circuit coupled to said output terminal of said integrating amplifier, and further including two further NOR circuits cross coupled together to form a flip flop, a motor coupled to drive said odometer indicator, a first transistor responsively coupled to said flip flop and coupled to pass electrical power to said motor for advancing said odometer indicator, and a second transistor responsively coupled to said flip flop and coupled to said capacitor for discharging said capacitor in response to said flip flop.
References Cited (Backward Citations)
US2539788A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-08 | 1976-02-07 | 1976-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-08 | 1980-02-07 | 1980-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-08 | 1984-02-07 | 1984-08-08 | $7700.00 | Window Closed / Lapsed |