Patent US1870754A successfully refreshed from Google Patents.
Patent US3697003A successfully refreshed from Google Patents.
US3697003A
Expired / Lapsed
US
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Grinding mill method and apparatus
Assignee: Industrial Nucleonics Corp
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Filing: 1970-02-04
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Granted: 1972-10-10
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Expires: 1990-02-04
Abstract
Abstract Rate of input ore fed to a grinding mill, including a hydrocyclone particle classifier in a recirculating loop, is controlled to maintain a predetermined relation between particle size and production rate. From the actual production rate and the predetermined relationship a value for the ratio of recycled solid feed rate to output or input solids feed rate is determined. The determined ratio value is compared with the actual ratio value derived from measurements to control input ore feed rate. The consistency of slurries fed to each of a rod mill, ball mill and the classifier is maintained constant.
Inventors
- 👤 Michael P Grant
- 👤 Edward J Freeh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 06:12
CPC Classifications
B; B02; B02C; B02C25/00
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
24 words
The system of claim 1 wherein the second signal deriving means includes means for monitoring the feed rate of solids in the output line.
Claim 2
Dependent Claim
58 words
The system of claim 1 wherein said mill includes means responsive to input ore and a supply of liquid for deriving a slurry of ore and liquid, and further including means responsive to the relative feed rates of solids and liquids fed to the slurry deriving means for controlling the consistency of solids and liquids in the slurry.
Claim 3
Dependent Claim
58 words
The system of claim 1 wherein said mill includes means responsive to recirculated ore and a supply of liquid for deriving a slurry of ore and liquid, and further including means responsive to the relative feed rates of solids and liquids fed to the slurry deriving means for controlling the consistency of solids and liquids in the slurry.
Claim 4
Dependent Claim
124 words
The system of claim 1 wherein said mill includes a rod mill responsive to input ore and a first supply of liquid for producing a first slurry of ore and liquid, a ball mill responsive to particles fed from the separating means back to the grinding means and a second supply of liquid for producing a second slurry of ore and liquid, a sump responsive to said first and second slurries and a third liquid supply for producing a third slurry fed to said separating means, and means responsive to the feed rates of solids and liquids fed to each of the rod mill, ball mill and sump for separately controlling the solid liquid consistency of each of the first, second and third slurries.
Claim 5
Independent Claim
161 words
A method of controlling the production rate of a grinding mill responsive to a supply of input ore, said mill including a recirculating looP with separating means for feeding particles generally having greater than a predetermined size back to a grinding means and for feeding particles generally having sizes equal to or less than the predetermined size to an output line, comprising effectively measuring the production rate of the mill, from the measured production rate and a function of the grindability of the input ore determining a desired relationship between the flow rate of particles in the recirculating loop and the production rate, determining an indication of the actual relationship between the flow rate of particles in the recirculating loop and the production rate, deriving an indication of the error between the desired and actual relationships, and in response to the error controlling the relative rates of the input ore feed and recirculated particle flow to maintain a desired mill operation.
Claim 6
Dependent Claim
19 words
A method, as defined in claim 6, wherein said desired relationship results in a substantially constant output particle size.
Claim 7
Dependent Claim
19 words
A method, as defined an claim 6, wherein said desired relationship is based upon particle size and economic factors.
Claim 8
Dependent Claim
65 words
The method as defined in claim 6 wherein said mill includes means responsive to input ore and a supply of liquid for deriving a slurry of ore and liquid, and controlling the relative feed rates of solids and liquids fed to the slurry deriving means to maintain the consistency of solids and liquids in the slurry substantially constant despite variation of input ore feed rate.
Claim 9
Dependent Claim
31 words
The method of claim 6 wherein the indication of the actual relationship is derived by: measuring the flow rate of particles in the recirculating loop, and combining the two rate measurements.
Claim 10
Dependent Claim
45 words
The method of claim 10 wherein the desired relationship is the desired ratio between the flow rate of the recirculating loop particles and the production rate, and the actual relationship is the actual ratio between the recirculating loop particle flow rate and the production rate.
Claim 11
Dependent Claim
45 words
The method of claim 6 wherein the desired relationship is the desired ratio between the flow rate of the recirculating loop particles and the production rate, and the actual relationship is the actual ratio between the recirculating loop particle flow rate and the production rate.
Claim 12
Dependent Claim
55 words
The system of claim 1 wherein said third signal deriving means includes a non-linear function generator responsive to said first signal indicative of the mill production rate for deriving said third signal as being indicative of a feed rate ratio of the particles fed back to the grinding means with respect to the input ore.
Claim 13
Dependent Claim
30 words
The system of claim 13 wherein said fourth signal deriving means includes means for deriving said fourth signal as being indicative of the ratio of the first and second signals.
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) | 1975-10-10 | 1976-04-10 | 1976-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-10 | 1980-04-10 | 1980-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-10 | 1984-04-10 | 1984-10-10 | $7700.00 | Window Closed / Lapsed |