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US 5,395,575 AGranted
Rotary reforming of thermoplastics extrudate
AssigneeGeneral Motors Corporation
InventorsBruce J. Stribbell, Donald L. Franck
Life of this patent
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AssigneeGeneral Motors Corporation
InventorsBruce J. Stribbell, Donald L. Franck
Estimating the term…
Production line and method for manufacturing strips of foil stabilized plastics moldings featuring a rotary reform machine that has a pair of reform wheels that are rotatably driven to profile the extrudate while matching the output speed of extrudate exiting from the extrusion die of a plastics extruder. The wheels have equal diameters and are motor driven at the same angular velocity so that forming dies in the wheels synchronize and cooperate to pressure mold spaced sections of the extrudate feeding therethrough to form high quality end corners with an offal section therebetween. A haul-off pulls the strip from the extruder die, the rotary reform machine, a water trough and flash trimmer and into a cutter where the offal is removed. The strip is maintained under a predetermined tension load by use of an adjustable friction brake on the stabilizer foil so that the heated plastics exiting the extruder will be uniform in initial profile, providing high quality extrudate feeding into the reforming wheels.
A method for reforming a band of hot plastics extrudate formed and produced by a plastics extruder into a profiled strip of plastics with a pair of rotatable roll forming wheels normally disposed in a general side-by-side relationship relative to one another and so that they provide an extrudate profiling interface at points where said wheels are closest to one another, comprising the steps of:
A rotary form production machine for reforming the shape of a heated strip of polymer with a ribbon-like elongated reinforcement member therein produced by strip-producing extruder comprising a support a first and second forming wheels operatively mounted on said support for receiving said strip heated and profiled by said extruder, said first and second forming wheels being operatively associated with one another to provide a reforming interface therebetween to effect reprofiling of said strip, a discrete end forming die operatively mounted in each of said wheels, a first of said dies in a first of said wheels having a profiling end portion to produce a sharp end corner in said strip above said reinforcing member, a second of said dies in a second of said wheels having a recess therein below said reinforcing member and cooperating with the first of said dies to receive polymer material displaced by said profiling end portion as offal below said reinforcement member on the underside of strip, and guide wheel means spaced from and associated with said first and second forming wheels for guiding said reprofiled strip from said machine.
A rotary forming machine for shaping an elongated strip of heated plastics as produced by plastics strip-forming tooling comprising a support, first and second forming wheels operatively mounted on said support and spaced from one another, motor means for rotatably driving said forming wheels, said first forming wheel being operatively mounted on said support and being operable to initially receive and solely support said strip, said second forming wheel being operatively associated with said first forming wheel to provide a profiling passage between adjacent arcuate portions of said first and second forming wheels for receiving said strip to effect the reprofiling of said strip as said forming wheels are rotatably driven, and a strip guide wheel associated with said second wheel and aligned therewith for holding said strip against a portion of the periphery of said second wheel and for guiding said strip away from said second wheel, and a drive mechanism for moving said first and second wheels between a position in which said heated strip of plastics is substantially tangent to only a first of said wheels and a position where said strip is aligned with the profiling passage.
A rotary reforming machine for reforming an elongated strip of heated plastics produced by plastics strip-forming tooling comprising a fixed upright, a carrier operatively mounted on said fixed upright, a support plate mounted for limited rotation relative to said fixed upright and said carrier, first and second forming wheels operatively mounted on said support plate in spaced relationship with respect to one another, motor means for rotatably driving said forming wheels, said first forming wheel having a circular periphery operative to initially receive and solely support said strip as initially produced by said strip forming tooling, said second forming wheel having a circular periphery operatively associated with said first forming wheel to provide a profiling passage between adjacent peripheral portions of said first and second forming wheels for receiving said strip and for effecting the reprofiling of said strip as said forming wheels are rotatably driven, and a strip guide wheel associated with said second forming wheel and aligned therewith for holding said strip against a portion of the periphery of said second wheel and for guiding said strip therefrom, and a drive mechanism for turning said support plate and said first and second wheels thereon between a position in which said heated strip of plastics produced by said strip forming tooling is supported by and is substantially tangent to the circular periphery of said first of said wheels and another position where said strip is aligned with the profiling passage.
Dependencies are inferred from the claim text.