US3840867A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluidic liquid sensing system
Assignee: United States Department of the Navy
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Filing: 1973-01-18
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Granted: 1974-10-08
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Expires: 1993-01-18
Abstract
Abstract A liquid level sensing system comprising a pair of sensors, a fluidic logic circuit and a warning device. The sensors are placed at two preselected measurement levels within a vented reservoir, each sensor including a hollow, vertical tube with a wire mesh cage containing a buoyant ball float of a diameter larger than the tube diameter attached to the tube bottom. Constant pressure gas is connected through a fixed orifice to the upper end of each tube and flows out of the bottom opening if the ball float is displaced by the liquid level below the bottom opening of the respective tube, activating a logic circuit and warning device communicating therewith. As the liquid level rises to the bottom opening of the respective tube, the ball float seals the opening, completely blocking gas flow, increasing pressure in the tube from a minimum to a maximum and deactivating the warning device through the logic circuit.
Inventors
- 👤 H Welk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:19
CPC Classifications
G; G01; G01F; G01F23/00; G01F23/14; G01F23/16; G01F23/161; Y; Y10; Y10T; Y10T137/00; Y10T137/206; Y10T137/2065
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
207 words
A liquid level condition sensing system for a container comprising, in combination: sensor means including an elongated tube adapted to be fixed vertically in the container having first, second and third openings communicating with each other therein, said second opening having a flared portion adjacent thereto communicating with the liquid at a preselected level, said third opening being intermediate said first and said second opening along the length of said tube, and having an orifice between said first and said third opening, a vented housing operatively secured to and surrounding said tube adjacent said second opening and a ball float captively contained within said housing and adapted to sealingly engage said flared portion when the liquid level approaches said second opening for obstructing the flow of fluid therefrom; fluidic pressure supply means operatively connected to said first opening; and fluidic logic means including first and second NOT gate fluidic amplifiers operatively connected in series, the input to said first amplifier being operatively connected to said sensor means third opening, and fluidic display means having an actuating and a deactuating port, the output from said first amplifier being operatively connected to the actuating port and the output from said second amplifier being operatively connected to the deactuating port.
Claim 2
Dependent Claim
207 words
A liquid level condition sensing system for a container comprising, in combination: sensor means including an elongated tube adapted to be fixed vertically in the container having first, second and third openings communicating with each other therein, said second opening having a flared portion adjacent thereto communicating with the liquid at a preselected level, said third opening being intermediate said first and said second opening along the length of said tube, and having an orifice between said first and said third opening, a vented housing operatively secured to and surrounding said tube adjacent said second opening and a ball float captively contained within said housing and adapted to sealingly engage said flared portion when the liquid level approaches said second opening for obstructing the flow of fluid therefrom; fluidic pressure supply means operatively connected to said first opening; and fluidic logic means including first and second NOT gate fluidic amplifiers operatively connected in series, the input to said first amplifier being operatively connected to said sensor means third opening, and fluidic display means having an actuating and a deactuating port, the output from said first amplifier being operatively connected to the actuating port and the output from said second amplifier being operatively connected to the deactuating port.
Claim 3
Dependent Claim
129 words
A level sensing system as set forth in claim 1, further comprising: said display means including means for converting fluidic pressure to an electrical signal having a fluidic input port and electrical input and output terminals operatively connected at said input port to the output from said first amplifier, a voltage source operatively connected to said converter means input terminal, a plurality of oscillators operatively connected in parallel at their inputs to said converter means output terminal for producing a timing signal and an audible signal, sequencer means having a plurality of inputs and an output operatively connected at said inputs to the respective outputs from said oscillators for intermittently emitting the audible signal, and alarm means operatively connected to said sequencer means output for displaying the audible signal.
Claim 4
Dependent Claim
130 words
A liquid level condition sensing system for a container comprising, in combination: a plurality of sensor means adapted to be placed in the container each having first, second and third openings communicating with each other therein, said second openings communicating with the liquid at different preselected levels, and an orifice between said first and said third opening; control means disposed outside of the container having first, second and third openings communicating with each other therein, said second opening communicating with the atmosphere, and an orifice between said first and said second opening; fluidic pressure supply means operatively connected to said sensor means and said control means first opening; and fluidic logic means operatively connected to said sensor means and said control means third opening for indicating the liquid level condition.
Claim 5
Dependent Claim
130 words
A liquid level condition sensing system for a container comprising, in combination: a plurality of sensor means adapted to be placed in the container each having first, second and third openings communicating with each other therein, said second openings communicating with the liquid at different preselected levels, and an orifice between said first and said third opening; control means disposed outside of the container having first, second and third openings communicating with each other therein, said second opening communicating with the atmosphere, and an orifice between said first and said second opening; fluidic pressure supply means operatively connected to said sensor means and said control means first opening; and fluidic logic means operatively connected to said sensor means and said control means third opening for indicating the liquid level condition.
Claim 6
Dependent Claim
44 words
A level sensing system as set forth in claim 3, further comprising: said sensor means each including ball float means formed to be captively guided to said second opening for obstructing the flow of fluid therefrom when the liquid level approaches said second opening.
Claim 7
Dependent Claim
53 words
A level sensing system as set forth in claim 4, further comprising: said sensor means including first and second elongated tubes each fixed vertically in the container having a flared portion adjacent said second opening and having said third opening between said first and said second opening along the length of said tube.
Claim 8
Dependent Claim
50 words
A level sensing system as set forth in claim 5, further comprising: said ball float means including a vented housing operatively secured to and surrounding each of said tubes adjacent saiD second opening and a ball float adapted to sealingly engage said flared portion being captively contained within said housing.
Claim 9
Dependent Claim
182 words
A level sensing system as set forth in claim 6, further comprising: said fluidic logic means including first and second NOT gate fluidic amplifiers operatively connected in series, the input to said first amplifier being operatively connected to said first tube third opening, fluidic display means having an actuating and a deactuating port, the output from said first amplifier being operatively connected to the actuating port and the output from said second amplifier being operatively connected to the deactuating port, third and fourth NOT gate fluidic amplifiers operatively connected in series, the input to said third amplifier being operatively connected to said second tube third opening, a fifth NOR gate fluidic amplifier and a sixth NOT gate fluidic amplifier, the input to said sixth amplifier being operatively connected to said control means third opening and the output from said sixth amplifier being operatively connected to a first input to said fifth amplifier a second input thereto being operatively connected to the output from said fourth amplifier, and the output from said fifth amplifier being operatively connected to said display means actuating port.
Claim 10
Dependent Claim
132 words
A level sensing system as set forth in claim 7, further comprising: said display means including means for converting fluidic pressure to an electrical signal having a fluidic input port and electrical input and output terminals operatively connected at said input port to the common outputs from said first and said fifth amplifiers, a voltage source operatively connected to said converter means input terminal, a plurality of oscillators operatively connected in parallel at their inputs to said converter means output terminal for producing a timing signal and an audible signal, sequencer means having a plurality of inputs and an output operatively connected at said inputs to the outputs from said oscillators for intermittently emitting the audible signal, and alarm means operatively connected to said sequencer means output for displaying the audible signal.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-07 | 1978-04-08 | 1978-10-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-07 | 1982-04-08 | 1982-10-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-07 | 1986-04-08 | 1986-10-08 | $7700.00 | Window Closed / Lapsed |