Coating processes – Immersion or partial immersion – Running lengths
Reexamination Certificate
1999-04-05
2001-05-08
Lamb, Brenda A. (Department: 1734)
Coating processes
Immersion or partial immersion
Running lengths
C427S434400, C118S420000, C118S117000
Reexamination Certificate
active
06228432
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to methods for the production of continuous composite materials from unidirectional reinforcing fibers and from thermoplasitics, wherein a longitudinally moved bundle of parallel continuous reinforcing fibers is preheated and impregnated with a continuously supplied thermoplastic melt, and whereupon the continuous composite material thus formed is cooled.
The invention relates, furthermore, to an apparatus suitable for carrying out a method of this kind.
2. Description of Related Art
A method of this kind is disclosed in DE 41 12 129 A1. In this German document, melted thermoplastic is applied to a moved fiber bundle from a fixed point; the fiber bundle is then impregnated with the thermoplastic, whereby at most 3% by weight of the plastic may be stripped off.
EP 0,102,159 B1 discloses a comparable method, in which viscosity-reducing additives are used in order to lower the melt viscosity.
EP 0,287,427 B1 and EP 0,415,517 A1 disclose methods, in which, in order to be impregnated, the fiber bundles are drawn in the region where the outlet of the thermoplastic melt is located by baffles.
SUMMARY OF THE INVENTION
An object on which the invention is based is to improve the initially described method for example, in terms of the degree and rate of impregnation that is obtainable, as well as to develop suitable apparatus for this purpose.
In accordance with these and other objects, there is provided a method for the production of continuous composite materials from unidirectional reinforcing fibers and from thermoplastics, comprising:
preheating a longitudinally moved bundle of parallel continuous reinforcement fibers, impregnating the bundle with a continuously supplied thermoplastic melt to form continuous composite material, cooling the continuous composite material, wherein the thermoplastic melt forms an elongate impregnation stage, introducing mechanical energy continuously into the impregnation stage in order to reduce the viscosity of the melt so as to form a zone of reduced melt viscosity, and continuously drawing the preheated fiber bundle through the zone of reduced melt viscosity.
In further accordance with the present invention there is provided an apparatus for the production of continuous composite materials comprising a heated closed impregnating appliance. The impregnating appliance comprises (i) at least one introduction nozzle for a fiber bundle be impregnated, (ii) a guide duct which connects the introduction nozzle to an outlet, (iii) at least one supply line for supplying thermoplastic melt to the appliance, the supply line opening into the guide duct, and (iv) at least one movable shearing element for applying mechanical energy to the thermoplastic melt in the guide duct.
Additional objects, features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects, features and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
REFERENCES:
patent: 3235437 (1966-02-01), Varlet
patent: 3640101 (1972-02-01), Wilcox
patent: 4883625 (1989-11-01), Glemet et al.
patent: 4957422 (1990-09-01), Glemet et al.
patent: 5137766 (1992-08-01), Mazanek et al.
patent: 5158806 (1992-10-01), Unger
patent: 5690741 (1997-11-01), Dürr et al.
patent: 6045876 (2000-04-01), Fellers et al.
patent: 41 12 129 (1992-10-01), None
patent: 0 102 159 (1984-03-01), None
patent: 0 287 427 (1988-10-01), None
patent: 0 397 506 (1990-11-01), None
patent: 0 415 517 (1991-03-01), None
Deinert Juergen
Segl Maximilian
Trutwig Leonhard
Foley & Lardner
Lamb Brenda A.
LandOfFree
Method and apparatus for the production of continuous... 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 and apparatus for the production of continuous..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for the production of continuous... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2474222