US3600574A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Radiometric method and apparatus for measuring and controlling foundry sand moisture
Assignee: Motors Liquidation Co
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Filing: 1969-05-12
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Granted: 1971-08-17
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Expires: 1989-05-12
Abstract
Abstract To measure the amount of water present in foundry sand continuously flowing through a chute, a probe within the chute carries a fast neutron source and a slow neutron detector to detect the amount of water in the sand. A gamma source in the probe and a gamma detector outside the chute measure the sand density. The detector output signals are arithmetically combined to give a signal proportional to percent moisture by weight. The signal may be used to control water addition to the sand.
Inventors
- 👤 Donald D Glaza
- 👤 Arthur D Block
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:47
CPC Classifications
G; G01; G01N; G01N23/00; G01N23/02; G01N23/06; G01N23/12
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
238 words
A method for measuring the amount of water in a continuously flowing mass of foundry sand containing from 2 percent to 4 percent by weight water comprising the steps of passing the mass through a gaging zone of fixed area, maintaining the gaging zone full of the mass, irradiating said mass with fast neutrons from a source of fast neutrons inserted into the path of said flowing mass in the gaging zone and simultaneously measuring the thermal neutron flux within said mass with a thermal neutron detector inserted into the path of the flowing mass thereby producing an electrical signal proportional to the thermal neutron flux, maintaining on each side of the neutron detector along the direction of flow sufficient sand such that the mass extends a distance exceeding the maximum distance from which neutrons thermalized by water influence the thermal neutron flux at the detector, at the same time determining the average density of the mass by irradiating the mass with gamma radiation from a gamma source inserted into the path of said flowing mass and simultaneously measuring the intensity of gamma radiations transmitted through the mass in a direction generally transverse to the direction of flow of the mass with a gamma detector outside the mass, thereby producing an electrical signal which is a function of density of the mass, and continuously computing from the said signals the amount of water in the mass of sand.
Claim 2
Independent Claim
202 words
A method for forming a mixture of water and foundry sand such that it contains an exact predetermined amount of water comprising the steps of drying the sand to the extent that it does not contain more water than that desired, flowing the sand continuously through an irradiation zone of fixed area, maintaining the zone full of the sand, irradiating the sand with fast neutrons from a source of fast neutrons inserted into the path of said flowing sand and simultaneously measuring the thermal neutron flux within said sand with a thermal neutron detector inserted into the path of said flowing sand thereby producing an electrical signal proportional to the thermal neutron flux, at the same time irradiating the sand with gamma radiation from a gamma source inserted into the path of the flowing sand in the irradiation zone and simultaneously measuring the intensiTy of gamma radiation transmitted through the sand with a gamma detector thereby producing an electrical signal as a function of sand density and proportional to the transmitted gamma radiation, continuously electrically computing from the said signals the amount of water in the sand, and continuously adding water in the amount required to provide the exact predetermined amount desired.
Claim 3
Dependent Claim
150 words
Apparatus for measuring the amount of water in foundry sand containing between 2 percent and 4 percent by weight water, said apparatus comprising a cylindrical chute defining a gaging zone of fixed area, means for continuously feeding sand through the chute, means for maintaining the gaging zone full of sand, a probe having a fast neutron source positioned adjacent a thermal neutron detector, means for moving said probe to a position adjacent the center of said chute, said detector producing an electrical signal proportional to thermal neutron flux, a source of gamma radiation in the probe, a gamma radiation detector outside the chute, the detector having an electrical signal as a function of sand density proportional to the intensity of gamma radiation transmitted through the sand, and an arithmetic circuit connected to the said detectors and responsive to the said signals for computing the amount of water in the sand.
Claim 4
Dependent Claim
186 words
Apparatus for measuring the water content of foundry sand comprising a cylindrical chute defining a gaging zone of fixed area, means for continuously feeding sand through the chute, means for maintaining the gaging zone full of sand, a probe centrally located within the chute in the gaging zone, means for obtaining an electrical signal which is a function of the amount of water in the sand including means for measuring the approximate water content of the sand comprising a fast neutron source and a thermal neutron detector within the probe so that the detector output is a signal which is a function of the thermal neutron flux which arises from the thermalization of the fast neutrons by the water in the sand; means for producing an electrical signal which is a function of the density of sand flowing through the chute comprising a gamma radiation source within the probe and a gamma radiation detector outside the chute wherein the gamma detector output is dependent on the sand density, and computer means responsive to the said electrical signals for calculating the amount of water in the sand.
Claim 5
Dependent Claim
152 words
Apparatus for controlling the percent of moisture in foundry sand comprising controllable means for adding water to the sand, means for continuously feeding sand through a chute, means for maintaining the gaging zone full of sand, a gaging zone including a portion of the chute having a fixed cross-sectional area, neutron source and detection means within the gaging zone and within the chute for producing a signal which is a function of said moisture, gamma source and detection means within the gaging zone for producing a signal which is a function of sand density, computer means responsive to the said signals for calculating the percent of moisture by weight of the foundry sand and producing an output proportional thereto, and means responsive to said output for controlling said controllable means whereby the rate of water addition to the sand is regulated to result in an accurate desired moisture content of the sand.
Claim 6
Dependent Claim
155 words
Apparatus for measuring the moisture content of foundry sand comprising a gaging cylinder defining a gaging zone of fixed area, means for continuously flowing sand through the gaging cylinder, means for maintaining the gaging zone full of sand, fast neutron source and thermal neutron detector means within the cylinder for measuring the moisture content of the foundry sand flowing through the gaging cylinder and producing a proportionate electrical output signal (N), a gamma source within the cylinder and gamma detector means outside the cylinder for measuring the density of the sand flowing through the cylinder and producing a correspondinG electrical output signal (G), and circuit means for calculating from the electrical signal the percent of moisture by weight of the foundry sand which equals the product of a first constant and the signal (G) plus the product of a second constant and the signal (N) plus a third constant, where the constants are empirically determined.
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) | 1974-08-16 | 1975-02-15 | 1975-08-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-16 | 1979-02-15 | 1979-08-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-16 | 1983-02-15 | 1983-08-17 | $7700.00 | Window Closed / Lapsed |