Patent US3887111A successfully refreshed from Google Patents.
US3887111A
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Density control feeder system
Assignee: K Tron Technologies Inc
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Filing: 1973-06-07
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Granted: 1975-06-03
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Expires: 1993-06-07
Abstract
Abstract A density control feeder system in which a material of variable density may be fed at a constant preselected density. The system may be comprised of a first and a second feeder. The first feeder may feed a material having a density less than the preselected density. The second feeder may feed material having a density greater than the preselected density. The density of the material fed by the two-feeders is computed and/or monitored. This density is compared with a set point density in a comparison circuit. The output of the comparison circuit controls the proportioning of mass flow set point pulses between the first and second feeders to maintain the density at the preselected value.
Inventors
- 👤 Kenneth W Bullivant
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:55
CPC Classifications
B; B65; B65B; B65B1/00; B65B1/30; B65B1/44
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
101 words
A method of feeding variable density material at a preselected density, comprising the steps of: feeding material having a density less than the preselected density through a first controllable digital feeder; feeding material having a density greater than the preselected density through a second controllable digital feeder; generating digital signals responsive to a preselected set point density and to the actual density of the material fed by both said first and second controllable feeders; and controlling the rate of feed of said first and second controllable feeders in response to said generated signals to provide a material having the preselected density.
Claim 2
Independent Claim
101 words
A method of feeding variable density material at a preselected density, comprising the steps of: feeding material having a density less than the preselected density through a first controllable digital feeder; feeding material having a density greater than the preselected density through a second controllable digital feeder; generating digital signals responsive to a preselected set point density and to the actual density of the material fed by both said first and second controllable feeders; and controlling the rate of feed of said first and second controllable feeders in response to said generated signals to provide a material having the preselected density.
Claim 3
Independent Claim
101 words
A method of feeding variable density material at a preselected density, comprising the steps of: feeding material having a density less than the preselected density through a first controllable digital feeder; feeding material having a density greater than the preselected density through a second controllable digital feeder; generating digital signals responsive to a preselected set point density and to the actual density of the material fed by both said first and second controllable feeders; and controlling the rate of feed of said first and second controllable feeders in response to said generated signals to provide a material having the preselected density.
Claim 4
Independent Claim
101 words
A method of feeding variable density material at a preselected density, comprising the steps of: feeding material having a density less than the preselected density through a first controllable digital feeder; feeding material having a density greater than the preselected density through a second controllable digital feeder; generating digital signals responsive to a preselected set point density and to the actual density of the material fed by both said first and second controllable feeders; and controlling the rate of feed of said first and second controllable feeders in response to said generated signals to provide a material having the preselected density.
Claim 5
Independent Claim
163 words
A method of feeding a variable density material at a preselected density, comprising the steps of: feeding material having material having a density less than the preselected density through a first controllable digital feeder; feeding material having a density greater than the preselected density through a second controllable digital feeder; digitally computing a digital composite density signal of the material fed by said first and second controllable feeders; digitally comparing the composite density signal with a digital density set point signal and generating a digital difference signal responsive to the difference between the composite density signal and the density set point signal and a polarity signal indicative of which signal exceeds the other; and producing a first digital signal for controlling the rate of feed of said first controllable feeder and a complementary second digital signal for controlling the rate of feed of said second controllable feeder, said first and second signals being responsive to the difference signal and to the polarity signal.
Claim 6
Independent Claim
163 words
A method of feeding a variable density material at a preselected density, comprising the steps of: feeding material having material having a density less than the preselected density through a first controllable digital feeder; feeding material having a density greater than the preselected density through a second controllable digital feeder; digitally computing a digital composite density signal of the material fed by said first and second controllable feeders; digitally comparing the composite density signal with a digital density set point signal and generating a digital difference signal responsive to the difference between the composite density signal and the density set point signal and a polarity signal indicative of which signal exceeds the other; and producing a first digital signal for controlling the rate of feed of said first controllable feeder and a complementary second digital signal for controlling the rate of feed of said second controllable feeder, said first and second signals being responsive to the difference signal and to the polarity signal.
Claim 7
Dependent Claim
165 words
Apparatus for feeding material having a variable density at a preselected density, comprising: a first controllable digital feeder for feeding material having a density less than the preselected density; a second controllable digital feeder for feeding material having a density greater than the preselected density; digital means for computing the density of material fed by said first and second controllable feeders; digital means for comparing the computed density with a set point density and generating a digital comparison signal responsive thereto; digital means for generating a digital mass flow set point signal; digital means for generating a first and second digital complementary signals from the mass flow set point signal in response to the comparison signal, said first complementary signal being supplied to said first controllable feeder as a set point signal and said second complementary signal being applied to said second controllable feeder as a set point signal whereby said first and second controllable feeders are controlled to produce the preselected set point density.
Claim 8
Dependent Claim
165 words
Apparatus for feeding material having a variable density at a preselected density, comprising: a first controllable digital feeder for feeding material having a density less than the preselected density; a second controllable digital feeder for feeding material having a density greater than the preselected density; digital means for computing the density of material fed by said first and second controllable feeders; digital means for comparing the computed density with a set point density and generating a digital comparison signal responsive thereto; digital means for generating a digital mass flow set point signal; digital means for generating a first and second digital complementary signals from the mass flow set point signal in response to the comparison signal, said first complementary signal being supplied to said first controllable feeder as a set point signal and said second complementary signal being applied to said second controllable feeder as a set point signal whereby said first and second controllable feeders are controlled to produce the preselected set point density.
Claim 9
Dependent Claim
61 words
Apparatus in accordance with claim 3 wherein said computing means comprises: a first digital density computer for computing the density of the material fed by said first controllable feeder; a second digital density computer for computing the density of material fed by said second controllable feeder; and digital means for combining the densities computed by said first and second density computers.
Claim 10
Dependent Claim
35 words
Apparatus in accordance with claim 3 including means for detecting whether the material having a density greater than the preselected density is being fed by the wrong controllable feeder and means for automatically compensating therefor.
Claim 11
Dependent Claim
95 words
Apparatus in accordance with claim 3 wherein said computing means comprises: digital means for adding the digital mass flow signalS of said first and second controllable feeders to provide a digital total mass flow signal: digital means for adding the digital volumetric flow signals of said first and second controllable feeders to provide a digital total volumetric flow signal; and digital means for dividing the total mass flow signal by the total volumetric flow signal to produce a digital signal indicative of the density of the material fed by said first and second controllable feeders.
Claim 12
Dependent Claim
49 words
Apparatus in accordance with claim 6 wherein the mass flow signals are pulse train signals and said adding means comprises an OR gate for receiving the mass flow pulse trains of said first and second controllable feeders and the output of said OR gate is applied to a counter.
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) | 1978-06-02 | 1978-12-02 | 1979-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-02 | 1982-12-02 | 1983-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-02 | 1986-12-02 | 1987-06-03 | $7700.00 | Window Closed / Lapsed |