Patent US3965623A successfully refreshed from Google Patents.
US3965623A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for trueing commutators and slip rings
Assignee: Individual
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Filing: 1975-07-07
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Granted: 1976-06-29
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Expires: 1995-07-07
Abstract
Abstract Trueing of commutators and slip rings of large industrial motors, generators, convertors and the like without dragover of copper into insulating spaces between commutator segments or loading of surface of the trueing tool is afforded by employing an ultra-high speed grinding wheel mounted on the shaft of a precision portable electric motor mounted for traversing across the width of the contact surface. A grinding wheel in a grit range of 150 to 180 is operated at a peripheral surface speed at the grinding point of at least 7,000 feet per minute (2100 meters per minute). This speed corresponds to a 4,500 rpm rotational speed for a 6-inch. (0.1524 meter) diameter wheel. The motor and wheel are of a size and weight enabling manual mounting on a traversing compound adjacent the surface to be ground.
Inventors
- 👤 Thaddeus Robert Grutza
- 👤 Kenneth Edward Grutza
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 06:03
CPC Classifications
B; B24; B24B; B24B5/00; B24B5/36; B24B5/363; B24B23/00; B24B23/08
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
151 words
The method of in-place trueing of a segmented copper commutator with a traversing grinding wheel which includes the improved steps of: 1. rotatably driving the commutator to be trued in its own journal support so that the commutator surface is in its normal running position; 2. simultaneously rotatably driving a peripheral grinding wheel surface exhibiting a grit size in the order of from about 150 to 180 at a peripheral speed of substantially at least 7,000 feet per minute; 3. contacting at least 1/2 to 3/4 inch of said peripheral surface against the commutator surface with forces in the order of from about 2 to 3 pounds; and 4. maintaining the relative surface speed of the commutator and the grinding wheel surface at ultra high speeds in excess of 7,000 feet per minute, thereby to remove the copper commutator material in the form of dust without drag over between the segments.
Claim 2
Independent Claim
151 words
The method of in-place trueing of a segmented copper commutator with a traversing grinding wheel which includes the improved steps of: 1. rotatably driving the commutator to be trued in its own journal support so that the commutator surface is in its normal running position; 2. simultaneously rotatably driving a peripheral grinding wheel surface exhibiting a grit size in the order of from about 150 to 180 at a peripheral speed of substantially at least 7,000 feet per minute; 3. contacting at least 1/2 to 3/4 inch of said peripheral surface against the commutator surface with forces in the order of from about 2 to 3 pounds; and 4. maintaining the relative surface speed of the commutator and the grinding wheel surface at ultra high speeds in excess of 7,000 feet per minute, thereby to remove the copper commutator material in the form of dust without drag over between the segments.
Claim 3
Dependent Claim
37 words
The method of in-place trueing as defined in claim 1, and canting the wheel at an angle relative to the axis of the spinning surface so that the minimum usable radius of the wheel can be decreased.
Claim 4
Independent Claim
123 words
The method of trueing a segmented copper commutator with a traversing grinding wheel which includes the improved steps of: 1. rotatably driving a peripheral grinding wheel surface exhibiting a grit size in the order of from about 150 to 180 at a peripheral speed of substantially at least 7,000 feet per minute; 2. contacting at least 1/2 to 3/4 inch of said peripheral surface against the commutator surface with forces in the order of from about 2 to 3 pounds; and 3. maintaining the relative surface speed of the commutator and the grinding wheel surface at ultra high speeds in excess of 7,000 feet per minute, thereby to remove the copper commutator material in the form of dust without drag-over between the segments.
Claim 5
Independent Claim
123 words
The method of trueing a segmented copper commutator with a traversing grinding wheel which includes the improved steps of: 1. rotatably driving a peripheral grinding wheel surface exhibiting a grit size in the order of from about 150 to 180 at a peripheral speed of substantially at least 7,000 feet per minute; 2. contacting at least 1/2 to 3/4 inch of said peripheral surface against the commutator surface with forces in the order of from about 2 to 3 pounds; and 3. maintaining the relative surface speed of the commutator and the grinding wheel surface at ultra high speeds in excess of 7,000 feet per minute, thereby to remove the copper commutator material in the form of dust without drag-over between the segments.
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) | 1979-06-29 | 1979-12-29 | 1980-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-29 | 1983-12-29 | 1984-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-29 | 1987-12-29 | 1988-06-29 | $7700.00 | Window Closed / Lapsed |