Device for improved reinforcing element with a continuous center core member with very long fiber reinforced thermoplastic wrapping
An improved reinforcing element, and devices and methods for producing a wrapped assembly reinforcing element comprising at least one center core member formed from at least one center core strand, wherein the at least one center core member is wrapped with a reinforced thermoplastic resin comprising complete fiber strand dispersion and wet out without breaking fiber filaments after cutting the fiber to a designated length in the wrapping resin. The resulting wrapped assembly may be used in a variety of ways, including virtually any construction project requiring a lightweight reinforcing member with high tensile and compression strength.
1. A device for forming a wrapped assembly comprising at least one center core member wrapped with reinforced thermoplastic resin, the wrapping having fully dispersed and fully wet out individual fiber filaments that retain their cut length, the device comprising:
an entrainment die having an inner chamber with an inner diameter and length and a volumetric capacity, at least one fiber guide nozzle in fluid communication with entrainment die inner chamber, a resin nozzle in fluid communication with the inner chamber of the entrainment die, wherein at least one continuous length of reinforcing fiber comprising a plurality of individual filaments is admitted through the at least one fiber guide nozzle, entrained and coated with molten resin;
a cutting assembly comprising a housing, cutting blade, bed knife and defining a cutting chamber having a length and a motor operatively connected with the cutting blade, the cutting assembly in fluid communication with the inner chamber of the entrainment die, wherein the at least one continuous length of entrained and coated reinforcing fiber is selectively cut to desired length; and
a down screw assembly comprising a barrel having an inner diameter, a down screw rotatingly housed within barrel and a motor operatively connected with the down screw, the down screw comprising an axis and two or more flites disposed thereon, each flite having a pitch and a depth, and at least two low shear apertures, the down screw assembly having a volumetric capacity that is substantially greater than said volumetric capacity of said entrainment die and the down screw capable of rotational speeds between 10 rpm and 100 rpm, wherein the cut fiber filaments are unbundled and wet out while retaining the selected cut length as the cut fiber filaments avoid high-pressure induced tension and shear within said down screw assembly and upon exiting of said down screw assembly through said at least two low shear apertures; and
a cross die in operative communication with the down screw assembly, the cross die comprising at least one entry port and at least one exit port, the at least one entry port and at least one exit port in fluid communication with an inner coating chamber therebetween whereby the at least one center core member passes through said inner coating chamber and is wrapped with reinforced thermoplastic resin containing the cut fiber filaments with retained selected cut length within said inner coating chamber.
2. The device of claim 1 , further comprising a main frame assembly to which the device is secured and a thermal barrier between the down screw assembly and the main frame assembly.
3. The device of claim 1 , further comprising a thermal separator operatively disposed between the down screw motor and the down screw barrel and down screw.
4. The device of claim 1 , further comprising the volumetric capacity of the entrainment die being exponentially less than the volumetric capacity of the down screw assembly.
5. The device of claim 1 , wherein the at least one entry port further comprises more than one individual core strand entry port.
6. The device of claim 1 , further comprising the exit port having a selectable cross-sectional shape and width.