US3921874A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of preparing short fibers of fine diameters
Assignee: Individual
•
Filing: 1973-09-04
•
Granted: 1975-11-25
•
Expires: 1993-09-04
Abstract
Abstract A method is provided for preparing short fibers of controlled lengths from continuous multifilament fiber bundles by impregnating the bundles with a liquid, tensioning the impregnated fiber bundles to obtain a high degree of fiber collimation, freezing the impregnating liquid to a solid, mechanically advancing the rigid bundle to a cutting edge, and mechanically cutting the fiber to desired lengths by mechanically driven blades. The impregnating liquid of the collected chopped short fibers is melted and the liquid subsequently removed by drying.
Inventors
- 👤 Raymond G Spain
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:53
CPC Classifications
D; D01; D01F; D01F9/00; D01F9/08; D01F9/12; D01F9/14; D01F9/32; D01G; D01G1/00; D01G1/02; D01G1/025; D01G1/027; Y; Y10; Y10T; Y10T225/00; Y10T225/10; Y10T225/16; Y10T225/30; Y10T225/371
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
118 words
A method for preparing short fibers of controllable lengths of multifilament bundles of fine diameter individual filaments comprising the steps of: impregnating the multifilament fiber bundles with a fiber inert liquid material; tensioning the impregnated multifilament fiber bundles to achieve a high degree of fiber collimation; freezing the impregnating liquid to form a solid composite comprised of the multifilament fiber bundles and a matrix of the frozen impregnating liquid; mechanically advancing the said solid composite beyond a cutting edge at a predetermined rate and severing the said solid composite incrementally to provide predetermined lengths of said solid composite; thawing the frozen impregnating liquid; and removing the impregnating liquid from the composite to provide plural fibers of desired length.
Claim 2
Independent Claim
118 words
A method for preparing short fibers of controllable lengths of multifilament bundles of fine diameter individual filaments comprising the steps of: impregnating the multifilament fiber bundles with a fiber inert liquid material; tensioning the impregnated multifilament fiber bundles to achieve a high degree of fiber collimation; freezing the impregnating liquid to form a solid composite comprised of the multifilament fiber bundles and a matrix of the frozen impregnating liquid; mechanically advancing the said solid composite beyond a cutting edge at a predetermined rate and severing the said solid composite incrementally to provide predetermined lengths of said solid composite; thawing the frozen impregnating liquid; and removing the impregnating liquid from the composite to provide plural fibers of desired length.
Claim 3
Dependent Claim
13 words
The process of claim 1 wherein the multifilament fiber bundle is essentially carbon.
Claim 4
Dependent Claim
12 words
The process of claim 2 wherein the matrix forming liquid is water.
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) | 1978-11-24 | 1979-05-26 | 1979-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-24 | 1983-05-26 | 1983-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-24 | 1987-05-26 | 1987-11-25 | $7700.00 | Window Closed / Lapsed |