US3601932A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Grinding method
Assignee: H AND H IND Inc
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Filing: 1969-04-02
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Granted: 1971-08-31
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Expires: 1989-04-02
Abstract
Abstract A precision flat surface is formed on a circular memory disk by rotating the disk on its axis and feeding a rotating annular grinding wheel axially into engagement with the disk under a substantially constant pressure. The grinding wheel is formed of a rigid foam material having abrasive particles dispersed therein and is supported for substantially friction-free axial movement.
Inventors
- 👤 Jesse W Elliott
- 👤 Ralph R Nevin
- 👤 Howard D Wilkin
- 👤 William G Huerth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:20
CPC Classifications
B; B24; B24B; B24B19/00; B24B1/00; B24B7/00; B24B7/10; B24B7/16
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
122 words
An improved method of forming a precision flat surface on a circular disk, comprising the steps of rotating the disk on its axis at a predetermined speed, forming a grinding wheel a rigid inflexible, foam material with abrasive particles dispersed therein, rotating the grinding wheel on an axis extending parallel to the axis of the disk and in offset relation, supporting the rotating said grinding wheel for substantially friction-free axial movement toward the disk, moving the rotating said grinding wheel axially into pressure engagement with the rotating disk, and holding said pressure engagement at a predetermined constant pressure for a predetermined time according to the rate of removal of material from the disk and the breakdown of particles from the grinding wheel.
Claim 2
Dependent Claim
122 words
An improved method of forming a precision flat surface on a circular disk, comprising the steps of rotating the disk on its axis at a predetermined speed, forming a grinding wheel a rigid inflexible, foam material with abrasive particles dispersed therein, rotating the grinding wheel on an axis extending parallel to the axis of the disk and in offset relation, supporting the rotating said grinding wheel for substantially friction-free axial movement toward the disk, moving the rotating said grinding wheel axially into pressure engagement with the rotating disk, and holding said pressure engagement at a predetermined constant pressure for a predetermined time according to the rate of removal of material from the disk and the breakdown of particles from the grinding wheel.
Claim 3
Dependent Claim
35 words
A method as defined in claim 1 including the step of reducing said pressure after said predetermined time while maintaining said pressure engagement to complete the finishing of the disk surface to a predetermined microfinish.
References Cited (Backward Citations)
US504386A
Cited
US1040470A
Cited
US1933373A
Cited
US1938875A
Cited
US2136036A
Cited
US2168596A
Cited
US2292229A
Cited
US3252775A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-08-30 | 1975-03-01 | 1975-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-30 | 1979-03-01 | 1979-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-30 | 1983-03-01 | 1983-08-31 | $7700.00 | Window Closed / Lapsed |