Coextrusion apparatus and method with rotating cord guidance
First Claim
1. Coextrusion apparatus having a central axis for producing a generally tubular elastomeric ply made up of at least first, second and third coaxial streams of elastomeric material which merge together at an annular extrusion orifice;
- said apparatus including;
a) stationary first channel forming means for forming an inner flow channel for delivering the first stream of elastomeric material to the extrusion orifice;
b) stationary second channel forming means for forming an intermediate flow channel for delivering the second stream of elastomeric material to the extrusion orifice, said second channel forming means being located concentrically about said first channel forming means;
c) stationary third channel forming means for forming an outer flow channel for delivering the third stream of elastomeric material to the extrusion orifice, said third channel forming means being located concentrically about said first and second channel forming means;
d) an inner guide element rotatably mounted between the stationary first and second channel forming means for delivering a plurality of individual reinforcing elements in a first helical pattern to the annular extrusion orifice for introducing into the interface of the merging first and second streams of elastomeric material;
e) an outer guide element rotatably mounted between the stationary second and third channel forming means for delivering a plurality of individual reinforcing elements in a second helical pattern opposed to the first helical pattern, to the annular extrusion orifice for introducing into the interface of the merging second and third streams of elastomeric material, with the second stream of elastomeric material separating the first and second helical patterns of reinforcing elements;
f) means for rotating said inner and outer guide elements in opposite directions with respect to each other; and
g) means for positioning discharge ends of the first, second and third channel forming means and discharge ends of the inner and outer guide elements, at an imaginary circle which lies in a plane which extends generally transverse to the axis of the coextrusion apparatus, whereby said first, second and third streams of elastomeric material and the first and second pluralities of reinforcing elements substantially simultaneously merge together at the extrusion orifice.
1 Assignment
0 Petitions
Accused Products
Abstract
Coextrusion apparatus for forming tubular elastomeric ply made up of first, second and third concentric streams of elastomeric material and a pair of coaxial helical patterns of individual reinforcing elements wound in opposite direction with respect to each other contained within the first and third streams of elastomeric material and separated by the second stream of elastomeric material. A pair of reinforcing element guides are rotatably mounted within the apparatus between stationary flow channels for the three streams of elastomeric material, and are rotated in opposite directions with respect to each other. The two helical patterns of reinforcing elements and three streams of elastomeric material merge together substantially simultaneously in concentric circles which lie in a plane generally perpendicular to a central axis of the coextrusion apparatus to form the tubular ply. A method for producing such a reinforced tubular elastomeric ply also is presented.
59 Citations
16 Claims
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1. Coextrusion apparatus having a central axis for producing a generally tubular elastomeric ply made up of at least first, second and third coaxial streams of elastomeric material which merge together at an annular extrusion orifice;
- said apparatus including;
a) stationary first channel forming means for forming an inner flow channel for delivering the first stream of elastomeric material to the extrusion orifice; b) stationary second channel forming means for forming an intermediate flow channel for delivering the second stream of elastomeric material to the extrusion orifice, said second channel forming means being located concentrically about said first channel forming means; c) stationary third channel forming means for forming an outer flow channel for delivering the third stream of elastomeric material to the extrusion orifice, said third channel forming means being located concentrically about said first and second channel forming means; d) an inner guide element rotatably mounted between the stationary first and second channel forming means for delivering a plurality of individual reinforcing elements in a first helical pattern to the annular extrusion orifice for introducing into the interface of the merging first and second streams of elastomeric material; e) an outer guide element rotatably mounted between the stationary second and third channel forming means for delivering a plurality of individual reinforcing elements in a second helical pattern opposed to the first helical pattern, to the annular extrusion orifice for introducing into the interface of the merging second and third streams of elastomeric material, with the second stream of elastomeric material separating the first and second helical patterns of reinforcing elements; f) means for rotating said inner and outer guide elements in opposite directions with respect to each other; and g) means for positioning discharge ends of the first, second and third channel forming means and discharge ends of the inner and outer guide elements, at an imaginary circle which lies in a plane which extends generally transverse to the axis of the coextrusion apparatus, whereby said first, second and third streams of elastomeric material and the first and second pluralities of reinforcing elements substantially simultaneously merge together at the extrusion orifice. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
- said apparatus including;
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10. A method of producing a generally tubular elastomeric ply including the steps of:
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providing three separate extruders; producing first, second and third annular streams of elastomeric materials, one stream from each of said extruders, said streams moving generally axially concentrically within an extrusion head toward an extrusion orifice; rotating first and second pluralities of individual reinforcing elements in opposite directions with respect to each other within the extrusion head to form two helical patterns of said reinforcing elements; and substantially simultaneously merging the two helical patterns of reinforcing elements into the three streams of elastomeric materials at the extrusion orifice with the second stream of elastomeric material separating the two helical patterns of reinforcing elements, and with the first and third streams of elastomeric material each coating a respective one of said helical patterns of reinforcing elements to form said tubular elastomeric ply. - View Dependent Claims (11, 12, 13, 14, 15, 16)
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Specification