Patent ID: 6474967
Filing Date: 2002-11-05
Classification: D01D

Abstract:
A die head assembly for producing meltblown bicomponent fibers in a meltblown apparatus, said assembly comprising:a die tip detachably mountable to an underside of an elongated support member, the support member having a first polymer supply passage and a second polymer supply passage defined therethrough; said die tip having a row of channels defined therethrough terminating at exit orifices along an edge of said die tip, said channels receiving and combining first and second polymers conveyed from the support member; an elongated recess defined in a top surface of said die tip, said recess defining an upper chamber of each said die tip channel; an upper breaker plate, a middle breaker plate, and a lower breaker plate removably supported in said recess, said breaker plates disposed in a stacked configuration in said recess; said upper breaker plate having receiving holes defined in an upper surface thereof to separately receive the polymers from the supply passages in the support member and channels to separately distribute the two polymers to said middle breaker plate; said middle breaker plate having a plurality of holes defined therethrough and disposed relative to said upper breaker plate channels so that each of the polymers is distributed to at least one said middle breaker plate hole and each said middle breaker plate hole receives only one polymer; said lower breaker plate having groupings of holes defined therealong such that one said grouping is disposed in each said chamber of said die tip channels, each of said lower breaker plate holes in fluid communication with one of said middle breaker plate holes such that each of the polymers is distributed to at least one of said lower breaker plate holes and each of said lower breaker plate holes receives only one polymer; a filter element disposed within said recess; and wherein at each said die tip channel, the first and second polymers conveyed from the support member supply passages flow through said breaker plates, are separately filtered by said filter element, and flow into said die tip channels as separate polymer streams corresponding to the number of said holes in said lower breaker plate and combine in said die tip channels prior to being extruded from said orifices as bicomponent polymer fibers.