Production of continuous filament mats
An installation and a method of preparing a continuous strand mat, the strands coming from at least one roving thrown onto a conveyor belt. In the method at least one roving package supported on a spindle is paid out via the outside, a rate of the pay-out imposed by a motor acting directly on the roving package so that linear speed of the paid-out roving is constant; then the roving passes through a nozzle, by passing through an entry and then an exit of the nozzle, the nozzle also provided with a transverse injection of at least one fluid mainly directed toward the exit of the nozzle, inducing a tension toward the bottom of the roving, the fluid also dividing the roving; and then the strands forming the roving are thrown in an oscillatory movement onto the conveyor belt.
1 - 11 . (canceled)
12 . A method of preparing a continuous strand mat, the strands coming from at least one roving thrown onto a conveyor belt, the method comprising:
paying-out at least one roving package supported on a spindle via the outside, a rate of the pay-out being imposed by a motor acting directly on the roving package so that the linear speed of the paid-out roving is constant; then
passing the roving through a nozzle, by passing through an entry and then an exit of the nozzle, the nozzle also provided with a transverse injection of at least one fluid, the at least one fluid being mainly directed toward the exit of the nozzle, inducing a tension toward a bottom of the roving, the at least one fluid also dividing the roving; and then
throwing the strands forming the roving in an oscillatory movement onto the conveyor belt.
13 . The method as claimed in claim 12 , wherein a speed of the roving paid out is measured by an encoder coupled to a pulley driven by the roving package.
14 . The method as claimed in claim 12 , wherein the nozzle presents the at least one fluid with a higher head loss at the entry than at the exit.
15 . The method as claimed in claim 12 , wherein the roving includes 2 to 50 strands.
16 . The method as claimed in claim 12 , wherein the fluid has a pressure of between 2 and 10 bar.
17 . The method as claimed in claim 12 , wherein the nozzle is also fed with water or with an aqueous solution or dispersion.
18 . The method as claimed in claim 12 , wherein the tension in the roving between the nozzle and the package is between 50 and 200 grams.
19 . An installation for manufacturing mats formed from continuous strands coming from roving packages and thrown onto a conveyor belt, comprising:
at least one roving package supported on a spindle;
means for paying out the roving coming from the package;
at least one nozzle through which the roving passes, by passing via an inlet and then an outlet of the nozzle, the nozzle also provided with a transverse injection of at least one fluid, the at least one fluid being directed mainly toward the exit of the nozzle, so as to induce a tension in the roving toward the exit; and
means for throwing the strands forming the roving onto the conveyor belt.
20 . The installation as claimed in claim 19 , wherein a pulley is driven by the paid-out roving, and an encoder is coupled to the pulley measuring the speed of the roving.
21 . The installation as claimed in claim 19 , wherein the nozzle is supported by the means for throwing.
22 . The installation as claimed in claim 19 , including at least two roving packages, each associated with a nozzle.