US3728061A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multi-layer spinnerette with head filter
Assignee: Mott Corp
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Filing: 1971-06-24
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Granted: 1973-04-17
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Expires: 1991-06-24
Abstract
Abstract The central cavity of a spinnerette head assembly for the extrusion of synthetic polymer filters is substantially filled with tubular filters closed at one end and communicating with extrusion orifices, the filter area being presented to inflowing plastic being at least twice the cross-sectional area of the central cavity, the tubular filter elements having at least an outer layer with a lesser degree of filtration and an inner layer with a greater degree of filtration.
Inventors
- 👤 L Mott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:32
CPC Classifications
D; D01; D01D; D01D4/00; B; B29; B29C; B29C48/00; B29C48/25; B29C48/36; B29C48/50; B29C48/69; D01D1/00; D01D1/10; D01D1/106; B29C48/03; B29C48/05; B29C48/254; B29C48/2545
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
170 words
A filter element for use in a spinnerette head for the extrusion of synthetic polymer fibers, said spinnerette head having a holder with means securing and sealing said filter element therein, said holder containing a large central cavity in front of said filter element, a pipe introducing plastic at extrusion pressures into the large central cavity of said holder, and a spinnerette disk containing extrusion apertures fixed to said holder below said filter element, said filter element comprising, in combination, a disk containing passages therethrough, and porous metal tubular filter elements fixed to said filter disk over each of said passages, each of said tubular elements having a fixed end fixed to said filter disk and a closed free end, said tubular filter elements having an outer filter area at least twice the cross-sectional area of said cavity, said tubular filter elements having an outer layer with a lesser degree of filtration passing larger particle sizes and an inner layer with a greater degree of filtration passing smaller particle sizes.
Claim 2
Dependent Claim
170 words
A filter element for use in a spinnerette head for the extrusion of synthetic polymer fibers, said spinnerette head having a holder with means securing and sealing said filter element therein, said holder containing a large central cavity in front of said filter element, a pipe introducing plastic at extrusion pressures into the large central cavity of said holder, and a spinnerette disk containing extrusion apertures fixed to said holder below said filter element, said filter element comprising, in combination, a disk containing passages therethrough, and porous metal tubular filter elements fixed to said filter disk over each of said passages, each of said tubular elements having a fixed end fixed to said filter disk and a closed free end, said tubular filter elements having an outer filter area at least twice the cross-sectional area of said cavity, said tubular filter elements having an outer layer with a lesser degree of filtration passing larger particle sizes and an inner layer with a greater degree of filtration passing smaller particle sizes.
Claim 3
Dependent Claim
71 words
The combination according to claim 1 wherein said tubular filter elements and said filter disk are formed of sintered powdered metal, said filter disk having an upper layer with a greater degree of filtration and a lower layer with a lesser degree of filtration, said upper layer being contiguous with said outer layer of said tubular elements and said lower layer being contiguous with said inner layer of said tubular elements.
Claim 4
Dependent Claim
70 words
The combination according to claim 2 wherein said tubular filter elements and the layers of said tubular filter elements taper, said tubular filter elements each containing a tapering passage, said layers of said filter disk and said tubular filter elements having a greater degree and a lesser degree of filtration being separately formed of sintered powdered metal, said filter elements being assembled by the placing of one layer against another.
Claim 5
Dependent Claim
56 words
The combination according to claim 3 wherein said layers having a lesser degree of filtration are formed from powdered metal of a larger mean particle size and said layers having a greater degree of filtration are formed from powdered metal of a smaller mean particle size, the layers being compacted to the same density and sintered.
Claim 6
Dependent Claim
25 words
The combination according to claim 2 wherein said filter disk and said tubular filter elements have an intermediate layer with an intermediate degree of filtration.
References Cited (Backward Citations)
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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) | 1976-04-16 | 1976-10-16 | 1977-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-16 | 1980-10-16 | 1981-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-16 | 1984-10-16 | 1985-04-17 | $7700.00 | Window Closed / Lapsed |