US3774829A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Yarn feeding device
Assignee: ITALIANO RICERCHE LAB
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Filing: 1972-03-08
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Granted: 1973-11-27
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Expires: 1992-03-08
Abstract
Abstract A yarn is wrapped around a portion of a rotary element which is rotating in the direction of feed. The periphery of the rotary element includes a plurality of openings through which an air stream is induced, the air stream tending to urge the yarn out of engagement with the rotary element, whereby the tension and frictional effect on the yarn around the rotary element may be varied in response to downstream conditions in order to obtain constant tension in the yarn being delivered to downstream machines regardless of the tension on the yarn as it is received at the rotary element from a supply source.
Inventors
- 👤 G Francia
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 15:55
CPC Classifications
D; D04; D04B; D04B15/00; D04B15/38; D04B15/48; D04B15/50; B; B65; B65H; B65H51/00; B65H51/02; B65H51/04; B65H51/06; B65H51/16; B65H2701/00; B65H2701/30; B65H2701/31; B65H2701/38
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
183 words
Yarn feeding device comprising a rotary element having means associated therewith for rotating said rotary element in a feed direction, said rotary element including a winding surface rotatable with said rotary element and around which the yarn being fed is at least partially wound, said rotary element also including means for limiting lateral movement of said yarn relative to said winding surface, said yarn feeding device also including means for generating air currents directed across the winding surface and having at least a radial component, said air currents being of a magnitude to normally urge said yarn away from said winding surface when the yarn is traversing the said device at a predetermined yarn tension, and said air currents being overcome by yarn tensioN in excess of said predetermined yarn tension to bring the yarn into variable engagement with the winding surface and achieve a winding arc variable with the upstream tension conditions and yarn features and responsive to downstream feed requirements, whereby a constant tension is obtained downstream which is independent upon the upstream tension during any delivery condition of the yarn.
Claim 2
Dependent Claim
183 words
Yarn feeding device comprising a rotary element having means associated therewith for rotating said rotary element in a feed direction, said rotary element including a winding surface rotatable with said rotary element and around which the yarn being fed is at least partially wound, said rotary element also including means for limiting lateral movement of said yarn relative to said winding surface, said yarn feeding device also including means for generating air currents directed across the winding surface and having at least a radial component, said air currents being of a magnitude to normally urge said yarn away from said winding surface when the yarn is traversing the said device at a predetermined yarn tension, and said air currents being overcome by yarn tensioN in excess of said predetermined yarn tension to bring the yarn into variable engagement with the winding surface and achieve a winding arc variable with the upstream tension conditions and yarn features and responsive to downstream feed requirements, whereby a constant tension is obtained downstream which is independent upon the upstream tension during any delivery condition of the yarn.
Claim 3
Dependent Claim
27 words
Device according to claim 1, wherein said rotary element continuously rotates at a constant speed, said speed of rotation being greater than the maximum downstream feed speed.
Claim 4
Dependent Claim
32 words
Device according to claim 1, wherein said yarn is disengaged from the surface of the rotary element by effect of the centrifugal air thrust even during periods of no downstream feed requirements.
Claim 5
Dependent Claim
27 words
Device according to claim 1 wherein said rotary element comprises a pulley race, the bottom of said race including holes or slits through which pressurized air exits.
Claim 6
Dependent Claim
46 words
Device according to claim 1, wherein said rotary element comprises a fan-shaped member, having vanes, recesses formed on the peripheral edges of said vanes for receiving and guiding the yarn, the vanes of said fan so arranged as to generate radial air currents during operation thereof.
Claim 7
Dependent Claim
44 words
Device according to claim 1, wherein said winding surface further includes means associated therewith for urging said yarn into a non-circumferential path, said urging means including wall portions adjacent said winding surface extending into said yarn path and engaging said yarn at prescribed points.
Claim 8
Dependent Claim
32 words
Device according to claim 1, wherein said air currents are inclined with respect to the relevant radial direction, to present a tangential component either along or opposite to the yarn feed direction.
References Cited (Backward Citations)
US3270932A
Cited
US3534893A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-26 | 1977-05-28 | 1977-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-26 | 1981-05-28 | 1981-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-26 | 1985-05-28 | 1985-11-27 | $7700.00 | Window Closed / Lapsed |