Textiles: fiber preparation – Working – Carding
Reexamination Certificate
1999-05-25
2001-11-20
Calvert, John J. (Department: 3741)
Textiles: fiber preparation
Working
Carding
C019S296000, C019S304000
Reexamination Certificate
active
06317932
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to collecting dry textile fiber and delivering the collected fiber to textile machinery and more particularly to forming the collected dry textile fiber into a batt to be fed to a textile machine.
BACKGROUND OF THE INVENTION
Many types of textile processing equipment, such as carding machines and airlay web formers, are designed to receive textile fiber from a bale in the form of a batt wherein the batt is formed of a collection of tufts of fiber. In the operation of such textile equipment, the tufts are conventionally pulled or taken whole into the textile equipment. Exceptionally large tufts may overload the textile equipment by providing too much fiber at once. Thus, it is preferred that the batts are formed with smaller tufts therein and the feed rates are set to accommodate the largest remaining tufts. In addition, bale opening equipment and perhaps other equipment are used to open the bales of fiber and break the tufts into smaller clumps of fiber to facilitate less overloading of equipment and higher feed rates.
To better appreciate certain aspects of the present invention, a common understanding or definition of the word “tuft” is provided in U.S. Pat. No. 5,606,776 to Freund et al. (hereafter, Freund) assigned to DuPont. In any event, it should be understood that the tufts are rather light, soft, readily deformable and tend to move with and be very reactive to any flow of air in their vicinity.
As noted above, the feed rates of carding equipment and airlay web formers are limited by the size of the largest tufts in the batt. The batts are typically formed by chute feeders which are designed to form a batt f preferably uniform thickness and density. Such chute feeders simply stack the tufts of fiber in a channel having a width approximately that of the carding machine and a thickness of approximately the thickness of the batt. Examples of conventional chute feeders are provided in a number of issued U.S. patents, such as U.S. Pat. Nos. 3,738,476; 4,154,485; 4,449,272; 4,930,190; and 5,157,809. Another example is Freund, mentioned above, which describes an apparatus for removing fiber from bales to form a batt of uniformly distributed fiber that is fed to a web forming mechanism and wherein the apparatus incorporates a chute feeder.
One of the difficulties in handling cut textile fiber is the tendency for fiber in the bin portion of the chute feeder to settle in mounds or piles when it is desirable that the fiber be generally uniformly dispersed. It is a problem whether the fiber is present as individualized fiber filaments, or in clumps, tufts or the like and especially combinations thereof. Non-uniform webs are often formed as a result of the non-uniform distribution in the fiber bed at the inlet side of the chute feeder. The mounds of fiber in the bin cause heavier or denser loaded areas in the batt that correspond generally to the mounds. The denser and heavier portions can be found throughout the process and the effect is observed in the final product by variation in basis weight, particularly in the cross-machine direction.
There have been various approaches to addressing this problem. For example, U.S. application Ser. No. 09/163,679 filed Sep. 30, 1998 and assigned to DuPont is directed to control of the fiber delivery by using several different flow paths to provide a number of small mounds rather than a single large mound. Even though this provides some improvement in the uniformity of the batt, it has been found that further improvement can be made by controlling the flow of the air stream that transports the fiber.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to overcome the above noted drawbacks of the prior art and to provide improved distribution of fiber in a fiber handling system.
It is an additional object of the present invention to provide a system for receiving fiber and providing a batt having improved lateral basis weight uniformity.
These objects of the present invention are achieved by the provision of a fiber handling apparatus that includes an inlet attached to a pneumatic conveyor system comprising transition ducts capable of directing the air stream above and perpendicular to the fiber bed and slowing the air stream to a velocity such that the fibers fall from the air stream. More specifically, these objects of the present invention are achieved by the provision of a fiber handling apparatus that includes an inlet attached to a pneumatic conveyor system comprising transition ducts which increase in cross-sectional size from the small end at the inlet to the large end where they connect with the bin portion of the chute feeder. The ducts are positioned at an angle from the horizontal sufficient to direct the air stream above and perpendicular to the fiber bed, thereby preventing the incoming airflow from impacting the walls of the transition ducts which would cause undesirable turbulence, and further, the combination of change in cross-sectional size, angle of inclination and length provides for decrease in the air flow velocity.
REFERENCES:
patent: 2316451 (1943-04-01), Page
patent: 3738476 (1973-06-01), Hullett et al.
patent: 3981047 (1976-09-01), Contractor et al.
patent: 4154485 (1979-05-01), Lytton et al.
patent: 4449272 (1984-05-01), Cash
patent: 4864693 (1989-09-01), Pinto et al.
patent: 4930190 (1990-06-01), Leifeld
patent: 5157809 (1992-10-01), Genevray
patent: 5606776 (1997-03-01), Freund et al.
patent: 5974631 (1999-11-01), Leifeld
patent: 36 32 934 A1 (1988-04-01), None
patent: 0 737 762 A (1996-10-01), None
patent: WO 96 29453 A (1996-09-01), None
patent: WO 99/18270 (1999-04-01), None
Dakin John M.
Giles Andrew J.
Jetton Nathan Cory
McCoy Todd A.
Sowell Lyles H.
Calvert John J.
E. I. Du Pont de Nemours and Company
Welch Gary L.
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