Claims
- 1. An apparatus for spinning yarn from fibers, comprising:
- a perforated fiber collection surface for collecting fibers, said collection surface having a pre-determined pattern of perforations defined therein arranged along a main sense of orientation, said fiber collection surface adapted for being rotated at a pre-determined rotational speed;
- a suction insert disposed generally under said collection surface and adapted to draw air through said perforations moving across a defined suction zone, whereby fibers are drawn to said collection surface and held against said collection surface along said main sense of orientation as said fiber collection surface rotates through said suction zone;
- a suction edge forming a collection line for said fibers at a pre-determined angle relative to a perpendicular line to the direction of movement of said collection surface, said suction edge defining the furthest boundary of said suction zone relative the rotational direction of said fiber collection surface whereby as said fibers are carried past said suction edge they leave said collection surface due to centrifugal forces and are drawn back into said suction zone by said suction insert, said fibers thereby gathering along said suction edge forming a fiber accumulation along said collection line, said fiber accumulation thereby having a pre-twist imparted thereto from the interaction of said centrifugal forces and said suction forces, said main sense of orientation of said perforations forming a predetermined non-zero angle with said collection line; and
- a twisting element comprising a pair of friction rollers, said fiber accumulation being drawn through said twisting element by yarn draw-off means, said twisting element disposed in-line relative the direction of yarn draw-off between said collection line and said yarn draw-off means, said twisting element configured to impart a final twist to said fiber accumulation thereby forming yarn having a predetermined degree of twist from said fiber accumulation.
- 2. The apparatus as in claim 1, wherein said perforations are disposed within said collection surface so that the space between said perforations lying along said main sense of orientation is less than the space between adjacent perforations not lying along the main sense of orientation.
- 3. The apparatus as in claim 1, further comprising a feeding channel disposed adjacent said suction zone whereby said fibers are drawn through said feeding channel towards said suction zone.
- 4. The apparatus as in claim 1, wherein said collection line forms a non-zero angle with a line perpendicular to the direction of movement of said collection surface.
- 5. The apparatus as in claim 1 wherein said collection line forms an angle with a line perpendicular to the direction of movement of said collection surface of substantially 0 degrees.
- 6. The apparatus as in claim 1, wherein said main sense of orientation of said perforations forms an angle with said collection line of less than 45 degrees.
- 7. The apparatus as in claim 1, wherein said fiber collection surface comprises a sieve roller configured to spin about its longitudinal axis.
- 8. The apparatus as in claim 1, wherein said fiber collection surface comprises a sieve band.
- 9. The apparatus as in claim 1, wherein said suction insert comprises a suction slit being rectangular in shape.
- 10. The apparatus as in claim 1, wherein said friction rollers are driven in a direction of rotation opposite that of said fiber collection surface.
- 11. The apparatus as in claim 1, wherein said friction rollers are driven at a rotation speed greater than that of said fiber collection surface.
- 12. A spinning process for producing yarn, said process comprising the steps of:
- defining suction holes in a spinning perforated collection surface along a predetermined main sense of orientation;
- drawing air through the suction holes in a suction zone of the collection surface;
- defining a collection line on the collection surface at a predetermined angle relative to a line perpendicular to the direction of movement of the spinning collection surface, the collection line being an edge of the suction zone, the main sense of orientation of the suction holes forming a predetermined non-zero angle with the collection line;
- introducing yarn fibers onto the spinning perforated collection surface at the suction zone so that the yarn fibers are orientated on the collection surface along the main sense of orientation of the suction holes;
- conveying the yarn fibers through the suction zone orientated along the main sense of orientation of the suction holes to the collection line;
- forming the yarn fibers into fiber accumulation along the collection line;
- pre-twisting the fiber accumulation at the collection line; and
- final twisting the fiber accumulation into a yarn with a pair of friction rollers disposed in-line relative the collection line in the direction of yarn draw-off, said final twisting being at a greater speed than said pre-twisting.
- 13. The process as in claim 12, wherein said step of defining suction holes in a spinning perforated collection surface along a predetermined main sense of orientation comprises spacing the suction holes so that the distance between adjacent suction holes along the main sense of orientation is least compared to adjacent suction holes not along the main sense of orientation.
- 14. The process as in claim 12, wherein said step of defining a collection line on the collection surface at a predetermined angle comprises defining the predetermined angle at a non-zero angle.
- 15. The process as in claim 12, including orienting the fibers along the main sense of orientation of the suction holes in the collection surface at an angle less than 45 degrees from the collection line.
- 16. The process as in claim 12, including orienting the fibers along the main sense of orientation of the suction holes in the collection surface at an angle of approximately 20 degrees from the collection line.
- 17. The process as in claim 12, wherein said pre-twisting comprises twisting the fiber accumulation at the collection line in a direction opposite to the direction of twist imparted during said twisting by the twisting element.
Priority Claims (1)
Number |
Date |
Country |
Kind |
4007607 |
Mar 1990 |
DEX |
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Parent Case Info
This is a division of application Ser. No. 07/666,043, filed Mar. 7, 1991 now U.S. Pat. No. 5,241,813.
US Referenced Citations (15)
Foreign Referenced Citations (7)
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382644 |
Mar 1987 |
ATX |
2618865A1 |
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DEX |
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DEX |
264944A1 |
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Divisions (1)
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Number |
Date |
Country |
Parent |
666043 |
Mar 1991 |
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