Patent US2554824A successfully refreshed from Google Patents.
Patent US3860804A successfully refreshed from Google Patents.
US3860804A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control system and method for ball mill and spiral classifier in closed circuit
Assignee: Westinghouse Electric Corp
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Filing: 1972-04-21
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Granted: 1975-01-14
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Expires: 1992-04-21
Abstract
Abstract A control system and method are disclosed for controlling the operation of a ball mill grinder device operative in conjunction with a spiral ore particle size classifier operative in a closed circuit arrangement. The sum of the new ore material feed rate and the recycled ore material feed rate of the ball mill is regulated to be substantially equal to the desired maximum material flow rate capacity of the ball mill. The desired control of the ball mill is determined in relation to the motor power consumed by the spiral classifier as a function of the recycle rate integrated over the period of screen retention time, and divided by that time, to provide the effective mean value of the recycle rate. The instantaneous value of the recycle rate, for each determined iteration time, is stored in a memory table and referenced in relation to the material retention time of the spiral classifier to establish the present recycle rate going back to the ball mill from the spiral classifier.
Inventors
- 👤 Richard E Rutman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:34
CPC Classifications
B; B02; B02C; B02C17/00; B02C17/18; B02C17/1805; B02C25/00; G; G05; G05D; G05D5/00; G05D5/04; G05D5/06
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
162 words
In a control system for an ore grinding circuit including at least one particle size spiral classifier operative with a ball mill grinding device, the combination of means for sensing the motor power of said classifier in relation to the ore material passing through said spiral classifier for eacH of a plurality of iteration periods related to the function operation of said spiral classifier, means for sensing the actual supply of new ore material to said ball mill grinding device, stored program control computer means for determining the recycle rate of ore material from said spiral classifier to said ball mill grinding device in relation to said motor power for at least a predetermined one of said iteration periods, and means for controlling the desired supply of new ore material to said ball mill grinding device for said one iteration period in accordance with a predetermined relationship including said actual supply of new ore material and said recycle rate of ore material.
Claim 2
Dependent Claim
162 words
In a control system for an ore grinding circuit including at least one particle size spiral classifier operative with a ball mill grinding device, the combination of means for sensing the motor power of said classifier in relation to the ore material passing through said spiral classifier for eacH of a plurality of iteration periods related to the function operation of said spiral classifier, means for sensing the actual supply of new ore material to said ball mill grinding device, stored program control computer means for determining the recycle rate of ore material from said spiral classifier to said ball mill grinding device in relation to said motor power for at least a predetermined one of said iteration periods, and means for controlling the desired supply of new ore material to said ball mill grinding device for said one iteration period in accordance with a predetermined relationship including said actual supply of new ore material and said recycle rate of ore material.
Claim 3
Dependent Claim
19 words
The control system of claim 1, with the determination of the recycle rate being in accordance with the relationship:
Claim 4
Dependent Claim
68 words
The control system of claim 1, with said desired supply of new ore material to said ball mill grinding device being controlled in accordance with the relationship: Werror WR - WA, where WR is determined in relation to a comparison of the desired total load of the ball mill grinder device with the ore material recycle rate and where WA is the actual supply of new ore material.
Claim 5
Dependent Claim
82 words
The control system of claim 1, with said stored program control computer means for determining the recycle rate being responsive to the operation of said classifier such that a recycle rate is established for each of said plurality of iteration periods related to the functional operation of said classifier, and with said sensed motor power of the classifier being representative of the sum of all the determined recycle rates during a predetermined ore material retention period including said plurality of iteration periods.
Claim 6
Dependent Claim
158 words
A control system for an ore material grinding circuit including a spiral classifier operative with an ore material grinding device, said control system including means for sensing the motor power of said classifier in relation to each of a plurality of iteration periods related to the functional operation of said classifier, means for sensing the actual supply of ore material to said grinding device, stored program control computer means for determining the recycle rate of the ore material returning to said grinding device for each of said iteration periods in relation to said motor power of said classifier and for determining a desired supply of ore material to said grinding device for each of said iteration periods in relation to said recycle rate and said actual supply of ore material, and means for controlling the supply of ore material to said grinding device for each of said iteration periods in accordance with said desired supply of ore material.
Claim 7
Dependent Claim
158 words
A control system for an ore material grinding circuit including a spiral classifier operative with an ore material grinding device, said control system including means for sensing the motor power of said classifier in relation to each of a plurality of iteration periods related to the functional operation of said classifier, means for sensing the actual supply of ore material to said grinding device, stored program control computer means for determining the recycle rate of the ore material returning to said grinding device for each of said iteration periods in relation to said motor power of said classifier and for determining a desired supply of ore material to said grinding device for each of said iteration periods in relation to said recycle rate and said actual supply of ore material, and means for controlling the supply of ore material to said grinding device for each of said iteration periods in accordance with said desired supply of ore material.
Claim 8
Dependent Claim
73 words
The control system of claim 5, with said stored program control computer means for determining the recycle rate being operative to determine a recycle rate for each of said plurality of iteration periods related to the functional operation of said classifier such that said motor power is related to the sum of all the recycle rates during a predetermined ore material retention time period including said plurality of iteration periods for said classifier.
Claim 9
Independent Claim
141 words
A method for controlling an ore material grinding circuit including at least one spiral classifier operative with a ball mill grinding device, said method including the steps of sensing the motor power of said classifier in relation to the ore material passing thRough said classifier for each of a plurality of iteration periods related to the functional operation of said classifier, sensing the actual supply of ore material passing to said ball mill grinding device, establishing the present recycle rate of ore material from said classifier to said ball mill grinding device for each of said iteration periods in relation to said motor power, and providing a desired ore material feed to said grinding device for each of said iteration periods in accordance with a desired relationship between the actual supply of ore material and said recycle rate of ore material.
Claim 10
Independent Claim
141 words
A method for controlling an ore material grinding circuit including at least one spiral classifier operative with a ball mill grinding device, said method including the steps of sensing the motor power of said classifier in relation to the ore material passing thRough said classifier for each of a plurality of iteration periods related to the functional operation of said classifier, sensing the actual supply of ore material passing to said ball mill grinding device, establishing the present recycle rate of ore material from said classifier to said ball mill grinding device for each of said iteration periods in relation to said motor power, and providing a desired ore material feed to said grinding device for each of said iteration periods in accordance with a desired relationship between the actual supply of ore material and said recycle rate of ore material.
Claim 11
Dependent Claim
45 words
The method of claim 7, with the step of establishing the present recycle rate of ore material being in consideration of a predetermined relationship with the recycle rate established for each of said plurality of iteration periods related to the functional operation of said classifier.
Claim 12
Dependent Claim
32 words
The method of claim 8, with the established recycle rate for each iteration period being updated such that said motor power is related to the sum of all the updated recycle rates.
Claim 13
Dependent Claim
163 words
In apparatus for controlling a ball mill grinder device operative with a spiral particle size classifier, the combination of means for sensing the motor power of said classifier for each of a predetermined number of iteration intervals related to the operation of said classifier with ore material passing through said classifier, stored program control computer means for determining an ore material recycle rate from said classifier to said ball mill grinder device for each of said iteration intervals, for determining a mean recycle rate in relation to the determined recycle rates for all of said iteration intervals, for determining a present recycle rate in relation to said motor power for the present iteration interval, and for modifying said determined recycle rates in accordance with a predetermined relationship including said mean recycle rate and said present recycle rate, and means for controlling the new material feed rate to said ball mill grinder device in accordance with a predetermined one of said determined recycle rates.
Claim 14
Dependent Claim
163 words
In apparatus for controlling a ball mill grinder device operative with a spiral particle size classifier, the combination of means for sensing the motor power of said classifier for each of a predetermined number of iteration intervals related to the operation of said classifier with ore material passing through said classifier, stored program control computer means for determining an ore material recycle rate from said classifier to said ball mill grinder device for each of said iteration intervals, for determining a mean recycle rate in relation to the determined recycle rates for all of said iteration intervals, for determining a present recycle rate in relation to said motor power for the present iteration interval, and for modifying said determined recycle rates in accordance with a predetermined relationship including said mean recycle rate and said present recycle rate, and means for controlling the new material feed rate to said ball mill grinder device in accordance with a predetermined one of said determined recycle rates.
Claim 15
Dependent Claim
39 words
The apparatus of claim 10, with said stored program control computer means determining said ore material recycle rate for each of said iteration periods in relation to a predetermined difference relationship between said sensed motor powers of said classifier.
Claim 16
Dependent Claim
40 words
The apparatus of claim 10, with said stored program control computer means determining said means recycle rate in relation to the sum of said determined recycle rates for all of said iteration intervals divided by said number of iteration intervals.
Claim 17
Dependent Claim
34 words
The apparatus of claim 10, with said stored program control computer means modifying said determined recycle rates in accordance with a predetermined ratio relationship between said mean recycle rate and said present recycle rate.
Claim 18
Dependent Claim
46 words
The apparatus of claim 10, with said stored program control computer means determining an ore material recycle rate from said classifier to said ball mill grinder device for each of said iteration intervals in accordance with the sensed change of motor power between successive iteration intervals.
Claim 19
Dependent Claim
45 words
The apparatus of claim 10, with said means for controlling the new material feed rate to said ball mill grinder device being responsive to the determined present recycle rate of the ore material presently being recycled from said classifier to said ball mill grinder device.
Claim 20
Dependent Claim
157 words
In a control system for an ore grinding circuit including at least one particle size spiral classifier operative with a ball mill grinding device, the combination of means for sensing the motor power of said classifier in relation to the ore material passing through said spiral classifier for each of a plurality of iteration periods related to the functional operations of said spiral classifier, means for sensing the actual supply of new ore material to said ball mill grinding device, means for deTermining the recycle rate of ore material from said spiral classifier to said ball mill grinding device in relation to said motor power for each of said plurality of iteration periods, and means for controlling the desired supply of new ore material to said ball mill grinding device for each of the iteration periods in accordance with a predetermined relationship including said actual supply of new ore material and said recycle rate of ore material.
Claim 21
Dependent Claim
157 words
In a control system for an ore grinding circuit including at least one particle size spiral classifier operative with a ball mill grinding device, the combination of means for sensing the motor power of said classifier in relation to the ore material passing through said spiral classifier for each of a plurality of iteration periods related to the functional operations of said spiral classifier, means for sensing the actual supply of new ore material to said ball mill grinding device, means for deTermining the recycle rate of ore material from said spiral classifier to said ball mill grinding device in relation to said motor power for each of said plurality of iteration periods, and means for controlling the desired supply of new ore material to said ball mill grinding device for each of the iteration periods in accordance with a predetermined relationship including said actual supply of new ore material and said recycle rate of ore material.
Claim 22
Dependent Claim
54 words
The control system of claim 16, with said recycle rate established for each of said plurality of iteration periods being related to the functional operation of said classifier, and with said sensed motor power of the classifier being related to the sum of the respective determined recycle rates for said plurality of iteration periods.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-01-13 | 1978-07-15 | 1979-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-13 | 1982-07-15 | 1983-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-13 | 1986-07-15 | 1987-01-14 | $7700.00 | Window Closed / Lapsed |