초록 ▼

A coextrusion block for siding communicates through respective separate circular inlets with two extruders at the inlet side of the coextrusion block while, at the outlet side, a curved kidney-shaped outlet is disposed about an inlet of acorn shape so that the outlets have boundaries lying along the

A coextrusion block for siding communicates through respective separate circular inlets with two extruders at the inlet side of the coextrusion block while, at the outlet side, a curved kidney-shaped outlet is disposed about an inlet of acorn shape so that the outlets have boundaries lying along the common circle which corresponds to the circular inlet of the broad-mouth die.

대표청구항 ▼

A coextrusion assembly for the extrusion of wide generally flat workpieces in the form of extruded siding, said assembly comprising: a first extruder for supplying a synthetic resin capstock material; a second extruder for supplying a synthetic resin substrate material; a coextrusion block having an

A coextrusion assembly for the extrusion of wide generally flat workpieces in the form of extruded siding, said assembly comprising: a first extruder for supplying a synthetic resin capstock material; a second extruder for supplying a synthetic resin substrate material; a coextrusion block having an upstream side and a downstream side, said block being formed at said upstream side with spaced apart first and second circular inlets opening on a common face of said block and connected respectively to said first and second extruders for receiving said capstock material and said substrate material, respectively, said block being formed at said downstream side with a first outlet for said capstock material and a second outlet for said substrate material, said first outlet having generally an elongated arcuate kidney shape with terminal lobes connected by an arcuate region extending arcuately around and strangling said second outlet, said second outlet having a generally acorn-shaped outline with opposite rounded segments of different radii of curvature having S-shaped transitions between them, said first and second outlets having diametrically opposite margins lying along a common circle, said coextrusion block being further formed with respective passages smoothly connecting said first inlet with said first outlet and said second inlet with said second outlet whereby flow from said first outlet wraps around flow from said second outlet; and a die having a circular inlet coaxially with said common circle and registering with both sides outlets, a wide mouth from which a flat workpiece consisting of said materials in respective layers emerges, and a passage flaring from said circular inlet of the die to said mouth.