US3864602A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preventing agglomeration of particles during screening due to electrical effects
Assignee: WEDCO Inc A NJ CORP
•
Filing: 1973-07-24
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Granted: 1975-02-04
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Expires: 1993-07-24
Abstract
Abstract Agglomeration of particles, e.g., plastic particles, during screening due to electrical effects is prevented by impressing a voltage on an insulated conductor resting directly on the screen.
Inventors
- 👤 Friedhelm R Feder
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 18:50
CPC Classifications
H; H05; H05F; H05F3/00
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
87 words
In the process of screening a mass of particles comprising feeding the particles to a moving screen for the screening thereof, the particles having a tendency to agglomerate during the screening operation due to electrical phenomena so that the screening is interfered with, the improvement for counteracting said tendency which comprises impressing a voltage on an insulated conductor resting directly on the screen during the screening, the voltage being sufficiently high to reduce agglomeration of the particles, but insufficient to cause a glow discharge along the conductor.
Claim 2
Dependent Claim
87 words
In the process of screening a mass of particles comprising feeding the particles to a moving screen for the screening thereof, the particles having a tendency to agglomerate during the screening operation due to electrical phenomena so that the screening is interfered with, the improvement for counteracting said tendency which comprises impressing a voltage on an insulated conductor resting directly on the screen during the screening, the voltage being sufficiently high to reduce agglomeration of the particles, but insufficient to cause a glow discharge along the conductor.
Claim 3
Dependent Claim
11 words
Process according to claim 1, the screen being a metal screen.
Claim 4
Dependent Claim
11 words
Process according to claim 1, the voltage being an alternating voltage.
Claim 5
Dependent Claim
14 words
Process according to claim 1, the voltage being an alternating voltage of 60 cycles.
Claim 6
Dependent Claim
10 words
Process according to claim 3, the voltage being 800-15,000 volts.
Claim 7
Dependent Claim
17 words
Process according to claim 2, the voltage being an alternating voltage of 60 cycles and 800-15,000 volts.
Claim 8
Dependent Claim
9 words
Process according to claim 6, the particles being plastic.
Claim 9
Dependent Claim
14 words
Process according to claim 3, the particles being polystyrene, polycarbonate, polypropylene, polyethylene, or polyvinylchloride.
Claim 10
Dependent Claim
9 words
Process according to claim 3, the screen being grounded.
Claim 11
Dependent Claim
26 words
Process according to claim 3, and a resistor operatively connected with the transformer and insulated conductor limiting the current in the conductor to about 0.1-15 milliamps.
Claim 12
Dependent Claim
26 words
Process according to claim 9, and a resistor operatively connected with the transformer and insulated conductor limiting the current in the conductor to about 0.5-15 milliamps.
Claim 13
Dependent Claim
11 words
Process according to claim 2, the voltage being an alternating voltage.
Claim 14
Dependent Claim
9 words
ProCess according to claim 3, the particles being polycarbonate.
Claim 15
Dependent Claim
92 words
Apparatus for screening of a mass of particles having a tendency to agglomerate during the screening due to electrical phenomena so that the screening is interfered with, comprising a. a screen, b. means for moving the screen to cause screening of particles fed to the screen, c. an insulated electrical conductor resting directly on the screen, d. a transformer having the output side thereof connected to said conductor for impressing a voltage on the conductor, e. the voltage rating of the transformer being insufficient to cause a glow discharge along the conductor.
Claim 16
Dependent Claim
92 words
Apparatus for screening of a mass of particles having a tendency to agglomerate during the screening due to electrical phenomena so that the screening is interfered with, comprising a. a screen, b. means for moving the screen to cause screening of particles fed to the screen, c. an insulated electrical conductor resting directly on the screen, d. a transformer having the output side thereof connected to said conductor for impressing a voltage on the conductor, e. the voltage rating of the transformer being insufficient to cause a glow discharge along the conductor.
Claim 17
Dependent Claim
11 words
Apparatus according to claim 14 the screen being a metal screen.
Claim 18
Dependent Claim
11 words
Apparatus according to claim 14 the transformer rating being 800-15,000 volts.
Claim 19
Dependent Claim
26 words
Apparatus according to claim 14, and a resistor operatively connected with the transformer and insulated conductor limiting the current in the conductor to about 0.5-15 milliamps.
Claim 20
Dependent Claim
26 words
Apparatus according to claim 16, and a resistor operatively connected with the transformer and insulated conductor limiting the current in the conductor to about 0.5-15 milliamps.
Claim 21
Dependent Claim
27 words
Apparatus according to claim 14, the conductor being secured to the screen so that lengths thereof are free to shake in response to shaking of the screen.
Claim 22
Dependent Claim
92 words
Apparatus for screening of a mass of particles having a tendency to agglomerate during the screening due to electrical phenomena so that the screening is interfered with, comprising a. two screens, b. means for moving the screens to cause screening of particles fed to the screens, c. an insulated electrical conductor resting directly on each screen, d. a transformer having the output side thereof connected to said conductors for impressing a voltage on the conductors, e. the voltage rating of the transformer being insufficient to cause a glow discharge along the conductor.
Claim 23
Dependent Claim
92 words
Apparatus for screening of a mass of particles having a tendency to agglomerate during the screening due to electrical phenomena so that the screening is interfered with, comprising a. two screens, b. means for moving the screens to cause screening of particles fed to the screens, c. an insulated electrical conductor resting directly on each screen, d. a transformer having the output side thereof connected to said conductors for impressing a voltage on the conductors, e. the voltage rating of the transformer being insufficient to cause a glow discharge along the conductor.
Claim 24
Dependent Claim
81 words
In the process of screening a mass of particles comprising feeding the particles to a moving screen for the screening thereof, the particles having a tendency to agglomerate during the screening operation due to electrical phenomena so that the screening is interfered with, the improvement which comprises impressing a voltage on an insulated conductor resting directly on the screen during the screening, the voltage being an alternative voltage of standard frequency, and being sufficiently high to reduce agglomeration of the particles.
Claim 25
Dependent Claim
81 words
In the process of screening a mass of particles comprising feeding the particles to a moving screen for the screening thereof, the particles having a tendency to agglomerate during the screening operation due to electrical phenomena so that the screening is interfered with, the improvement which comprises impressing a voltage on an insulated conductor resting directly on the screen during the screening, the voltage being an alternative voltage of standard frequency, and being sufficiently high to reduce agglomeration of the particles.
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) | 1978-02-03 | 1978-08-05 | 1979-02-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-03 | 1982-08-05 | 1983-02-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-03 | 1986-08-05 | 1987-02-04 | $7700.00 | Window Closed / Lapsed |