US3642080A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Weighing apparatus
Assignee: Driver Southall Ltd
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Filing: 1969-06-16
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Granted: 1972-02-15
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Expires: 1989-06-16
Abstract
Abstract Weighing apparatus including a weigh pan, a discharge door and permanent magnetic closure means for retaining the door in a closed position, wherein electromagnetic means are provided to coact with the permanent magnet so that current passed through the electromagnet opens the door by magnetic repulsion of the permanent magnet.
Inventors
- 👤 Arthur Walter Forman
- 👤 Mark Sitkowski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 18:11
CPC Classifications
G; G01; G01G; G01G21/00; Y; Y10; Y10S; Y10S177/00; Y10S177/05
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
178 words
A weighing apparatus comprising a weigh pan having a material-receiving body, a discharge door hinged for angular movement relative to the body, and permanent magnet closure means comprising independent first and second permanent magnet poles for exerting attractive magnetic force tending to retain the door in closed position, characterized by electromagnetic means having a least one pole Whose magnetic axis is aligned substantially in the direction of angular movement of the door, said electromagnetic means comprising respectively coacting first and second electromagnet poles disposed in opposed relation to said permanent magnet poles, and means whereby one of said electromagnet poles is selectively operatively energizable upon current flow in a predetermined direction to supplement the attractive force of a respective one of the permanent magnet poles for retaining the door in closed position and the other of said electromagnet poles in selectively operatively energized upon current flow in a predetermined direction and upon deenergization of said one electromagnet pole to open the door by magnetic repulsion between said other electromagnet pole and the other of said permanent magnet poles.
Claim 2
Dependent Claim
178 words
A weighing apparatus comprising a weigh pan having a material-receiving body, a discharge door hinged for angular movement relative to the body, and permanent magnet closure means comprising independent first and second permanent magnet poles for exerting attractive magnetic force tending to retain the door in closed position, characterized by electromagnetic means having a least one pole Whose magnetic axis is aligned substantially in the direction of angular movement of the door, said electromagnetic means comprising respectively coacting first and second electromagnet poles disposed in opposed relation to said permanent magnet poles, and means whereby one of said electromagnet poles is selectively operatively energizable upon current flow in a predetermined direction to supplement the attractive force of a respective one of the permanent magnet poles for retaining the door in closed position and the other of said electromagnet poles in selectively operatively energized upon current flow in a predetermined direction and upon deenergization of said one electromagnet pole to open the door by magnetic repulsion between said other electromagnet pole and the other of said permanent magnet poles.
Claim 3
Dependent Claim
34 words
Apparatus according to claim 1, characterized in that the permanent magnet means and the electromagnetic means are respectively mounted one on the material-receiving body of the weigh pan and one on the discharge door.
Claim 4
Dependent Claim
35 words
Apparatus according to claim 1, characterized in that said permanent magnet means and said electromagnetic means are respectively mounted one on a fixed frame of the weighing apparatus and the other on the discharge door.
Claim 5
Dependent Claim
39 words
Apparatus according to claim 1, characterized in that a pole face of the permanent magnet means and an interacting face of a pole of the associated electromagnet attracted thereby are a predetermined distance apart when the door is closed.
Claim 6
Dependent Claim
13 words
Apparatus according to claim 4, characterized by means for adjusting said predetermined distance.
Claim 7
Dependent Claim
28 words
Apparatus according to claim 1, characterized in that the door is pivotally mounted at the vicinity of its upper edge for swinging angular movement about a horizontal axis.
Claim 8
Dependent Claim
34 words
Apparatus according to claim 6, wherein the center of gravity of the door is arranged to urge it away from the closed position when it is not influenced by said permanent magnet closure means.
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) | 1975-02-14 | 1975-08-16 | 1976-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-14 | 1979-08-16 | 1980-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-14 | 1983-08-16 | 1984-02-15 | $7700.00 | Window Closed / Lapsed |