US3788145A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid sampling
Assignee: Pro-Tech Inc
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Filing: 1973-03-14
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Granted: 1974-01-29
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Expires: 1993-03-14
Abstract
Abstract Equipment for sampling liquid at intervals controllable by adjusting the rate of accumulation of sample-propulsion fluid is provided with means for extending the intervals at which samples are taken and the duration of the taking of such samples. A pressure-responsive switching valve effective to interconnect accumulated propellant to a sampling locus in the liquid at a given accumulated pressure is partially shielded from sensing the pressure drop resulting from such interconnection, thus extending the period required for the pressure to reaccumulate to the switching level. The range from shortest to longest sampling interval is adjustable by varying the degree of such shielding.
Inventors
- 👤 M Irwin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:57
CPC Classifications
G; G01; G01N; G01N1/00; G01N1/02; G01N1/10; G01N1/14
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
116 words
In apparatus for sampling liquid from a body thereof, including means for accumulating propellant fluid at a given rate from a source thereof under superatmospheric pressure and normally closed switching valve means between the accumulating means and a sampling locus in the body of liquid, the valve means having a pressure-sensing line connected to the accumulating means and being adapted to open at a given actuating pressure and to reclose at a given decrement in pressure sensed thereby, the improvement comprising fluid-impeding means located in the pressure-sensing line and effective to reduce the rate of pressure drop therein upon actuation and thus to increase the open time of the valve means for a given pressure decrement.
Claim 2
Dependent Claim
116 words
In apparatus for sampling liquid from a body thereof, including means for accumulating propellant fluid at a given rate from a source thereof under superatmospheric pressure and normally closed switching valve means between the accumulating means and a sampling locus in the body of liquid, the valve means having a pressure-sensing line connected to the accumulating means and being adapted to open at a given actuating pressure and to reclose at a given decrement in pressure sensed thereby, the improvement comprising fluid-impeding means located in the pressure-sensing line and effective to reduce the rate of pressure drop therein upon actuation and thus to increase the open time of the valve means for a given pressure decrement.
Claim 3
Dependent Claim
40 words
Apparatus according to claim 1, including means offering only minimal impedance between accumulating means and valve means in the event of pressure increments to be sensed, but offering greater impedance therebetween in the event of pressure decrements to be sensed.
Claim 4
Dependent Claim
121 words
In liquid-sampling apparatus operable by fluid from a source thereof under superatmospheric pressure to propel successive samples of liquid from a body thereof at desired intervals, an accumulator for fluid from such source, flow-regulating means interposed between the source and the accumulator, a normally closed pressure-responsive switching valve interposed between the accumulator and a sampling locus in the body of liquid, the switching valve being adapted to open at a predetermined level of fluid pressure in the accumulator and to reclose at a lower predetermined level of fluid pressure therein, and means for delaying the sensing of such pressure decrement temporarily upon opening of the valve and consequent flow of accumulated fluid to the sampling locus to propel a sample therefrom.
Claim 5
Dependent Claim
121 words
In liquid-sampling apparatus operable by fluid from a source thereof under superatmospheric pressure to propel successive samples of liquid from a body thereof at desired intervals, an accumulator for fluid from such source, flow-regulating means interposed between the source and the accumulator, a normally closed pressure-responsive switching valve interposed between the accumulator and a sampling locus in the body of liquid, the switching valve being adapted to open at a predetermined level of fluid pressure in the accumulator and to reclose at a lower predetermined level of fluid pressure therein, and means for delaying the sensing of such pressure decrement temporarily upon opening of the valve and consequent flow of accumulated fluid to the sampling locus to propel a sample therefrom.
Claim 6
Dependent Claim
27 words
Liquid-sampLing apparatus according to claim 3, wherein the delaying means comprises a unidirectional flow restrictor interposed between the accumulator and the pressure-sensing portion of the switching valve.
Claim 7
Dependent Claim
35 words
Liquid-sampling apparatus according to claim 3, wherein the delaying means is adjustable for varying the delay time by means of a flow-regulating valve interposed between the accumulator and the pressure-sensing portion of the switching valve.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-28 | 1977-07-30 | 1978-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-28 | 1981-07-30 | 1982-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-28 | 1985-07-30 | 1986-01-29 | $7700.00 | Window Closed / Lapsed |