US3862497A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pipeline pig
Assignee: TDW DELAWARE Inc A CORP OF DE
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Filing: 1973-07-25
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Granted: 1975-01-28
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Expires: 1993-07-25
Abstract
Abstract A pipeline pig is provided with at least two wheels mounted thereon to roll along the inner wall of the pipeline. Pulses are generated as each wheel turns a predetermined revolution such as by a magnet carried by each of the wheels for movement past a magnetic flux responsive switch carried by the mechanism mounting the wheels. Thus, as each wheel revolves, its respective magnet moves past the switch to actuate it and thereby provide a pulse responsive to the distance moved by the pig. Each of the flux responsive switches is connected to a circuit means for providing an output responsive to the largest count obtained from the individual flux responsive switches over an increment of travel of the pig.
Inventors
- 👤 Burton Vernooy
- 👤 Robert L Kendall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:53
CPC Classifications
G; G01; G01P; G01P3/00; G01P3/42; G01P3/50; G01P3/54; G01M; G01M3/00; G01M3/005; G01P3/56; G01P3/60; F; F16; F16L; F16L2101/00; F16L2101/30
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
204 words
A pipeline pig for indicating the distance from one point to another point or points in a pipeline comprising, in combination: a pig having a central body and means carried by the body for impeding flow of pipeline fluid past the pig so that the pig is propelled by such fluid along the pipeline; a plurality of wheels; means for mounting each of said wheels on said body; a plurality of pulse generating means each including a magnetic flux means carried by each of said wheels for rotative movement past a portion of one of said mounting means and pig body and means situated at each of such portions to produce a discrete pulse only when the respective one of said flux means moves therepast to provide a plurality of pulse trains each having a pulse repetition rate related to the rate of revolution of the wheel associated therewith; and comparison means for comparing the pulse repetition rates of the respective pulse trains and providing an output signal normally responsive to the pulse train having the highest pulse repetition rate over an increment of travel of the pig, said output signal having a property related to the pulse repetition rate of such pulse train.
Claim 2
Dependent Claim
204 words
A pipeline pig for indicating the distance from one point to another point or points in a pipeline comprising, in combination: a pig having a central body and means carried by the body for impeding flow of pipeline fluid past the pig so that the pig is propelled by such fluid along the pipeline; a plurality of wheels; means for mounting each of said wheels on said body; a plurality of pulse generating means each including a magnetic flux means carried by each of said wheels for rotative movement past a portion of one of said mounting means and pig body and means situated at each of such portions to produce a discrete pulse only when the respective one of said flux means moves therepast to provide a plurality of pulse trains each having a pulse repetition rate related to the rate of revolution of the wheel associated therewith; and comparison means for comparing the pulse repetition rates of the respective pulse trains and providing an output signal normally responsive to the pulse train having the highest pulse repetition rate over an increment of travel of the pig, said output signal having a property related to the pulse repetition rate of such pulse train.
Claim 3
Dependent Claim
104 words
The pig of claim 1 wherein said comparison means includes circuit means for so comparing the repetition rates of said pulse trains over predetermined, successive count periods each including a plurality of pulses to provide at least one pulse selection signal in response to the pulse train having the higher repetition rate during said count period, and gate means responsive to said pulse selection signal to provide said output signal in response to the last mentioned pulse train substantially until a change in said pulse selection signal indicates that another of said pulse trains has the higher repetition rate during a succeeding count period.
Claim 4
Dependent Claim
110 words
The pig of claim 2 wherein said circuit means includes a plurality of counters each connected to one of said pulse generating means for counting a predetermined number of pulses therefrom, and a bi-stable circuit connected to be responsive to each of said counters to provide said pulse selection signal in response to one of said counters counting said predetermined number of pulses, and wherein said gate means includes a plurality of gate circuits each connected to said bi-stable circuit to be responsive to said pulse selection signal, each of said gate circuits also being connected to one of said pulse generating means to be responsive to the pulses therefrom.
Claim 5
Dependent Claim
100 words
The pig of claim 3 including two of said wheels mounted thereon each having one of said pulse generating means associated with it so that two of such pulse trains are provided, and including two counters each for counting a predetermined number of pulses in one of said pulse trains, and wherein said bi-stable circuit is a flip-flop including two inputs with each of said inputs being connected to one of said counters, to provide two distinctive pulse selection signals, and including two gate circuits each connected to said flip-flop to be responsive to one of said pulse selection signals.
Claim 6
Dependent Claim
16 words
The pig of claim 1 wherein each of said magnetic flux means is a permanent magnet.
Claim 7
Dependent Claim
35 words
The pig of claim 1 wherein each of said magnetic flux responsive means is a switch having contacts which open and close responsive to the magnetic flux means on the wheel passing by the switch.
Claim 8
Dependent Claim
16 words
The pig of claim 6 wherein each of said magnetic flux means is a permanent magnet.
Claim 9
Dependent Claim
39 words
The pig of claim 1 wherein said plurality of wheels are mounted by said mounting means on said pig body so as to be disposed at different circumferential positions about said pipeline when said pig is in said pipeline.
Claim 10
Dependent Claim
20 words
The pig of claim 8 wherein said mounting means are located at positions on said pig body approximately 180* apart.
Claim 11
Dependent Claim
29 words
The pig of claim 1 further including indicator means connected to be responsive to said output signal to provide a readout proportional to the distance traversed by said pig.
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) | 1978-01-27 | 1978-07-29 | 1979-01-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-27 | 1982-07-29 | 1983-01-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-27 | 1986-07-29 | 1987-01-28 | $7700.00 | Window Closed / Lapsed |