Textiles: manufacturing – Thread finishing – Surface modification of running length
Patent
1998-02-25
2000-07-18
Vanatta, Amy B.
Textiles: manufacturing
Thread finishing
Surface modification of running length
28276, 28254, D02J 108, D02G 116
Patent
active
06088892&
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The invention relates to a method for the aerodynamic texturing of yarn with a texturing nozzle having a continuous yarn duct, at one end of which the yarn is supplied and at the other end is delivered as textured yarn, compressed air being supplied into the yarn duct at a supply pressure higher than 4 bar in a central portion and the air jet being accelerated to supersonics in a widening acceleration duct. The invention also relates to a texturing nozzle, a nozzle head and its use, with a continuous yarn duct having a compressed air supply, on one side of which yarn can be supplied and on the other side of which texturing can be carried out.
STATE OF THE ART
Two types of texturing nozzle have proved successful in air jet texturing technology. They differ according to the type of compressed air supply into the yarn duct. One is the air jet texturing nozzle operating by the radial principle. The compressed air is supplied via one or more predominantly radially arranged air ducts, for example according to EP-PS 88 254. Texturing nozzles operating by the radial principle are used mainly with yarns requiring rather low excess deliveries lower than 100%. In special cases, with so-called effect yarns, an excess delivery of up to 200% can be permitted briefly. The second type involves the axial principle. The compressed air is guided here via axially directed ducts into an enlarged chamber of the yarn duct. A solution of this type is shown in EP-PS 441 925. Texturing nozzles operating by the axial principle are successfully used mainly with very high excess deliveries of up to 300% and sometimes even up to 500%. The two practical solutions differ in particular by the design of the nozzle aperture in the region of the nozzle outlet. The solution according to EP-PS 441 925 has a nozzle aperture corresponding to a Laval nozzle in front of the outlet end. The Laval nozzle is characterised by a very small opening angle of a maximum of 8.degree. to 10.degree.. If the opening angle is equal to or smaller than the so-called ideal Laval angle, the air speed in the nozzle aperture can be increased smoothly beyond the sound limit, providing the air pressure is above a critical pressure ratio at the narrowest point of the Laval nozzle. Laval noticed that the limit zone of the increase in speed shifts into the nozzle even in an ideal nozzle when the air pressure is reduced. A shock wave with the known compression surges can form. Compression surges are avoided whenever possible in most specialist fields in fluid mechanics. The texturing process is more complex since not only a supersonic flow with a gas is required but the yarn simultaneously also has to be guided centrally through the nozzle and processed by the shock wave. To compensate all losses of flow, air pressures higher than 4 bar and usually higher than 6 bar are used during air jet texturing. The theoretical maximum speed of the air (at a temperature of 20.degree. C., a preliminary pressure tending to infinity and an ideal Laval angle lower than 10.degree.) is about 770 m/sec. In reality, the maximum possible air speed at 12 bar is between 500 and 550 m/sec, that is lower than Mach 2. Reference is made to a scientific investigation in "Chemiefasern/Textilindustrie" May 1981. According to the most widely adopted specialist opinion, the texturing process as such is due to the effect of the compression surges which are a phenomenon of the supersonic flow. The yarn textured with a texturing nozzle having an ideal Laval angle could now be taken as a gauge of quality. Other nozzle shapes could be sought on the basis of this given quality. According to EP-PS 88 254, the applicants actually achieved an alternative nozzle shape with a trumpet-shaped nozzle mouth, the so-called Hemajet nozzle. The trumpet shape appears to lie outside Laval's laws only at first sight. A second investigation (International Textile Bulletin Yarn Production 3/83) revealed that a supersonic flow is also produced with the trumpet shape, maximum air speeds having been measured i
REFERENCES:
patent: 2958112 (1960-11-01), Hall
patent: 3093878 (1963-06-01), Fieldman et al.
patent: 3474613 (1969-10-01), Joarder et al.
patent: 3525134 (1970-08-01), Coon
patent: 3638291 (1972-02-01), Yngve
patent: 3751767 (1973-08-01), Marshall
patent: 3754694 (1973-08-01), Reba
patent: 3822543 (1974-07-01), Edagawa et al.
patent: 3828404 (1974-08-01), Peckinpaugh et al.
patent: 3916493 (1975-11-01), Ethridge
patent: 3983609 (1976-10-01), Pike
patent: 4040154 (1977-08-01), Riley
patent: 4064686 (1977-12-01), Whitted et al.
patent: 4070815 (1978-01-01), Negishi et al.
patent: 4157605 (1979-06-01), Agers
patent: 4251904 (1981-02-01), Sano et al.
patent: 4507833 (1985-04-01), Simmen
patent: 4535516 (1985-08-01), Egbers et al.
patent: 4574436 (1986-03-01), Cullen, Jr.
patent: 4581886 (1986-04-01), Coll-tortosa
patent: 4633550 (1987-01-01), McAliley
patent: 4641504 (1987-02-01), Runkel
patent: 4691947 (1987-09-01), Burkhardt et al.
patent: 4922593 (1990-05-01), Gorrafa
patent: 4945618 (1990-08-01), Gorrafa
patent: 5003677 (1991-04-01), Krenzer
patent: 5020199 (1991-06-01), Gorrafa
patent: 5140729 (1992-08-01), Simmen
patent: 5157819 (1992-10-01), Hodan
patent: 5182900 (1993-02-01), Horak et al.
patent: 5231743 (1993-08-01), Goldstein
patent: 5241730 (1993-09-01), Simmen et al.
patent: 5511295 (1996-04-01), Shah
patent: 5579566 (1996-12-01), Burkhardt et al.
patent: 5640745 (1997-06-01), Bertsch et al.
patent: 5713113 (1998-02-01), Demir
A Demir, "A Study of Air-Jet Texturing Nozzles: The Effects of Nozzle Configuration on the Air Flow", Transactions of the ASME, Series B: Journal of Engineering for Industry, 112(1) :97-104 (1990).
Bertsch Gotthilf
Schwarz Erwin
Heberlein Fibertechnology, Inc.
Vanatta Amy B.
LandOfFree
Method of aerodynamic texturing, texturing nozzle, nozzle head a does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of aerodynamic texturing, texturing nozzle, nozzle head a, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of aerodynamic texturing, texturing nozzle, nozzle head a will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2024017