Patent US1989736A successfully refreshed from Google Patents.
Patent US3727708A successfully refreshed from Google Patents.
US3727708A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Force balance weigh cell
Assignee: Acurex Corp
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Filing: 1971-12-20
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Granted: 1973-04-17
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Expires: 1991-12-20
Abstract
Abstract A force balance weigh cell having a movable weight structure supported by a flexure system which allows only vertical movement, a photocell position sensing system provides an electrical output signal which is indicative of displacement of the weight structure, the signal is employed to develop a current which is proportional to displacement and rate of displacement and an electromagnetic means receive the signal and apply a restoring force to the weight support structure. The signal is a measure of the weight or force applied to the structure.
Inventors
- 👤 A Adler
- 👤 W Kennedy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:18
CPC Classifications
G; G01; G01G; G01G7/00; G01G7/02; G01G7/04; G01G3/00; G01G3/08; Y; Y10; Y10S; Y10S177/00; Y10S177/06
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
144 words
A force balance weigh cell comprising a movable weigh structure, means for supporting said structure for movement in a vertical direction, means forming a beam of light, a lens mounted on said movable weigh structure to receive and focus said beam, a photocell including a pair of spaced sensitive photocell elements for receiving the focused beam positioned such that when the structure is in its normal position the signal output from each of the photocells is substantially equal and when the structure is displaced the output is unequal, means for receiving said displacement signals and providing an output signal which is proportional to displacement and rate of displacement, means responsive to the output signal to apply a restoring force to the structure, and means for measuring said output signal to give a force signal proportional to the force or weight on the weigh structure.
Claim 2
Dependent Claim
144 words
A force balance weigh cell comprising a movable weigh structure, means for supporting said structure for movement in a vertical direction, means forming a beam of light, a lens mounted on said movable weigh structure to receive and focus said beam, a photocell including a pair of spaced sensitive photocell elements for receiving the focused beam positioned such that when the structure is in its normal position the signal output from each of the photocells is substantially equal and when the structure is displaced the output is unequal, means for receiving said displacement signals and providing an output signal which is proportional to displacement and rate of displacement, means responsive to the output signal to apply a restoring force to the structure, and means for measuring said output signal to give a force signal proportional to the force or weight on the weigh structure.
Claim 3
Dependent Claim
74 words
A force balance weigh cell as in claim 1 wherein said means for receiving the displacement signAl and providing an output signal proportional to displacement and rate of displacement comprises a differential amplifier means for receiving and amplifying the signal, a differentiating amplifier connected to receive the output from the differential amplifier, and a summing amplifier adapted to receive the output of the differential amplifier and the differentiating amplifier and provide said output signal.
Claim 4
Dependent Claim
90 words
A force balance weigh cell as in claim 1 including a housing surrounding said weigh structure, a pair of support flexure elements connected between the housing and the weigh structure near one end of the weigh structure and housing and extending radially at right angles to one another away from the structure, and three flexure elements connected between the housing and the structure near the other end of the structure and housing, two of said members arranged parallel to one another and at right angles with respect to the other.
Claim 5
Dependent Claim
35 words
A force balance weigh cell as in claim 1 in which said means for supporting said structure for vertical movement comprises a five-element flexure system arranged and positioned to form a statically determinant support system.
Claim 6
Dependent Claim
48 words
A force balance weigh cell as in claim 4 including a magnet structure disposed below the weigh structure and a coil carried at the lower end of the support structure to cooperate with the magnetic structure and serving to receive the output signal and generate the restoring force.
Claim 7
Dependent Claim
51 words
A force balance weigh cell as in claim 5 including a thermal sensor mounted to sense the temperature at said coil and provide an output temperature signal and means for receiving said temperature signal and said force signal and correcting the force signal to compensate for thermal expansion of the coil.
Claim 8
Dependent Claim
81 words
A force balance weigh cell comprising a movable weigh structure, a five-element flexure system arranged and positioned to form a statically determinant support system for supporting said structure for movement in a vertical direction, means providing an output signal which is proportional to displacement and rate of displacement of said structure, means responsive to said signal to apply a restoring force to the structure, and means to measure said signal to apply a restoring force to provide an indication of weight.
Claim 9
Dependent Claim
81 words
A force balance weigh cell comprising a movable weigh structure, a five-element flexure system arranged and positioned to form a statically determinant support system for supporting said structure for movement in a vertical direction, means providing an output signal which is proportional to displacement and rate of displacement of said structure, means responsive to said signal to apply a restoring force to the structure, and means to measure said signal to apply a restoring force to provide an indication of weight.
Claim 10
Dependent Claim
90 words
A force balance weigh cell as in claim 7 including a housing surrounding said weigh structure, a pair of said flexure elements connected between the housing and the weigh structure near one end of the weigh structure and housing and extending radially at right angles to one another away from the structure, and three flexure elements connected between the housing and the structure near the other end of the structure and housing, two of said members arranged parallel to one another and at right angles with respect to the other.
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) | 1976-04-16 | 1976-10-16 | 1977-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-16 | 1980-10-16 | 1981-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-16 | 1984-10-16 | 1985-04-17 | $7700.00 | Window Closed / Lapsed |