US5238633A — Method and apparatus for recycling plastic waste …

Claim 1

Independent Claim 193 words

An apparatus for producing an extruded product comprising: first extruder means having an inlet for receipt of a plastic waste particulate, an outlet for exhausting a melted plastic, and a first conveyor rotating within the bore of the first extruder means; second extruder means having an inlet for receipt of a melted plastic, an outlet for exhausting a melted plastic, and a second conveyor, the second extruder means inlet positioned to receive the plastic melt from the outlet of the first extrusion means; cross-head die means for extruding melted plastic from the outlet of the second extruder means, the cross-head die means forming the melted plastic in the desired product cross-section; means for introducing fiber rovings into the extruding melted plastic, the fiber introduction means cooperating with the cross-head die means so as to introduce the fiber rovings during extrusion and positioning the rovings parallel and juxtaposed to the surface of the extruded product; and cooling means for forming and cooling the profile of the extruded product upon extrusion from the cross-head die means, the cooling means pulling the extruded profile along its length while tensioning the fiber rovings within the melted plastic.

Claim 2

Independent Claim 193 words

An apparatus for producing an extruded product comprising: first extruder means having an inlet for receipt of a plastic waste particulate, an outlet for exhausting a melted plastic, and a first conveyor rotating within the bore of the first extruder means; second extruder means having an inlet for receipt of a melted plastic, an outlet for exhausting a melted plastic, and a second conveyor, the second extruder means inlet positioned to receive the plastic melt from the outlet of the first extrusion means; cross-head die means for extruding melted plastic from the outlet of the second extruder means, the cross-head die means forming the melted plastic in the desired product cross-section; means for introducing fiber rovings into the extruding melted plastic, the fiber introduction means cooperating with the cross-head die means so as to introduce the fiber rovings during extrusion and positioning the rovings parallel and juxtaposed to the surface of the extruded product; and cooling means for forming and cooling the profile of the extruded product upon extrusion from the cross-head die means, the cooling means pulling the extruded profile along its length while tensioning the fiber rovings within the melted plastic.

Claim 3

Dependent Claim 109 words

The apparatus of claim 1 wherein the first extruder means further comprises: a feed section of the conveyor having a deep root that extends for at least 50 percent of the overall length of the first extruder means between the inlet and the outlet, a metering section having a shallow root and positioned adjacent the outlet end of the first extruder means, and a melting section between the feeding section and the metering section, the melting section including a progressive enlargement of the root from that of the feed section to that of the metering section, the length of the melting section being approximately one lead of the conveyor.

Claim 4

Dependent Claim 28 words

The apparatus of claim 2 wherein the outlet of the first extruder means exposes the melted plastic to ambient conditions so as to devolitize and depressurize the melt.

Claim 5

Dependent Claim 70 words

The apparatus of claim 3 wherein the fiber introduction means further comprises guide bars fixed on opposite sides of the cross-head die means, the rovings passing over the guide bars and into a channel for melted plastic within the cross-head die, and insert tubes positioned on the cross-head die for directing the rovings into the flow of plastic within the channel so as to be extruded along with the plastic.

Claim 6

Independent Claim 262 words

An apparatus for forming an extruded product comprising: an extruding portion having a first extruder and a second extruder, and a forming portion located at the discharge end of the extruding portion, the first extruder adapted to receive a particulate plastic feed stock material and to melt the plastic particulate, the second extruder adapted for receipt of the melted plastic from the first extruder, for compressing and conveying the melted plastic and for extruding the plastic into the forming means, the first extruder comprising an inlet for receipt of the plastic particulate, an outlet for exhausting the melted plastic, a constant bore, and a first conveyor rotating within the bore, the first conveyor having a constant lead, and including a feed section, a melting section and a metering section, the feed section having a deep root that extends for at least fifty percent (50%) of the overall length between the inlet and the outlet, the metering section having a shallow root, and the melting section having a progressive enlargement of the root from that of the feed section to that of the metering section, the length of the melting section being approximately one lead of the conveyor, the second extruder comprising an inlet for receipt of the melted plastic from the outlet of the first extruder, an outlet for exhausting the melted plastic, a constant bore, and a second conveyor, the second conveyor including a progressively decreasing lead along its entire length, the first and second extruder adapted to limit the mixing and vortex of the melted plastic during the extrusion process.

Claim 7

Independent Claim 262 words

An apparatus for forming an extruded product comprising: an extruding portion having a first extruder and a second extruder, and a forming portion located at the discharge end of the extruding portion, the first extruder adapted to receive a particulate plastic feed stock material and to melt the plastic particulate, the second extruder adapted for receipt of the melted plastic from the first extruder, for compressing and conveying the melted plastic and for extruding the plastic into the forming means, the first extruder comprising an inlet for receipt of the plastic particulate, an outlet for exhausting the melted plastic, a constant bore, and a first conveyor rotating within the bore, the first conveyor having a constant lead, and including a feed section, a melting section and a metering section, the feed section having a deep root that extends for at least fifty percent (50%) of the overall length between the inlet and the outlet, the metering section having a shallow root, and the melting section having a progressive enlargement of the root from that of the feed section to that of the metering section, the length of the melting section being approximately one lead of the conveyor, the second extruder comprising an inlet for receipt of the melted plastic from the outlet of the first extruder, an outlet for exhausting the melted plastic, a constant bore, and a second conveyor, the second conveyor including a progressively decreasing lead along its entire length, the first and second extruder adapted to limit the mixing and vortex of the melted plastic during the extrusion process.

Claim 8

Dependent Claim 66 words

The apparatus of claim 5 wherein the second conveyor of the second extruder includes a transition portion wherein the root increases toward the outlet of the second extruder, the transition portion extending for approximately one lead of the conveyor, and a metering portion between the transition portion and the outlet of the second extruder, the root of the metering portion of the second conveyor being shallow.

Claim 9

Dependent Claim 71 words

The apparatus of claim 6 further comprising means for introducing fiber rovings into the melted plastic discharged into the forming portion, the fiber introduction means positioning the rovings parallel and juxtaposed to at least one surface of the extruded product, the forming portion cooling the profile of the extruded plastic discharged from the second extruder and pulling the profile of the plastic while tensioning the fiber rovings within the melted plastic.

Claim 10

Dependent Claim 70 words

The apparatus of claim 7 further comprising cross-head die means for extruding melted plastic from the outlet of the second extruder into the forming means, the cross-head die means forming the melted plastic in the desired product cross-section and the fiber introduction means cooperating with the cross-head die means so as to introduce the fiber rovings during extrusion and position the rovings parallel to the surface of the extruded product.

Claim 11

Independent Claim 130 words

A method of making a thin profile extruded product from a commingled plastic waste feed stock, comprising the steps of: feeding a particulate commingled plastic waste feed stock; extruding the particulate through a first extruder and melting the particulate by compaction and compression within the first extruder; extruding the particulate substantially without mixing or vortexing the melted plastic through a second extruder, the melted plastic substantially separating within the second extruder by resin type, extruding the melted plastic extruded within the second extruder through a die to form a thin profile cross-section; introducing fiber rovings into the profile of the plastic melt extruding through the die; pulling the extruded plastic profile from the die by tensioning the fiber rovings within the profile; and cooling the extruded and pulled plastic profile.

Claim 12

Independent Claim 130 words

A method of making a thin profile extruded product from a commingled plastic waste feed stock, comprising the steps of: feeding a particulate commingled plastic waste feed stock; extruding the particulate through a first extruder and melting the particulate by compaction and compression within the first extruder; extruding the particulate substantially without mixing or vortexing the melted plastic through a second extruder, the melted plastic substantially separating within the second extruder by resin type, extruding the melted plastic extruded within the second extruder through a die to form a thin profile cross-section; introducing fiber rovings into the profile of the plastic melt extruding through the die; pulling the extruded plastic profile from the die by tensioning the fiber rovings within the profile; and cooling the extruded and pulled plastic profile.

Claim 13

Dependent Claim 26 words

The method of claim 9 wherein the fiber rovings are introduced parallel to at least two opposing surfaces of the extruded profile, juxtaposed to the surfaces.

Claim 14

Dependent Claim 21 words

The method of claim 10 wherein the fiber rovings are positioned approximately 0.020 inches from the surfaces of the extruded profile.

Claim 15

Independent Claim 293 words

An apparatus for forming an extruded product from a mixed, contaminated, post-consumer and/or industrial plastic waste, the apparatus comprising: an extruding portion having a first extruder and a second extruder, and a forming portion located at the discharge end of the extruding portion, the first extruder adapted to receive a particulate plastic feed stock material and to melt the plastic particulate, the second extruder adapted for receipt of the melted plastic from the first extruder, for compressing and conveying the melted plastic and for extruding the plastic into the forming means, the first extruder comprising an inlet for receipt of the plastic waste particulate, an outlet for exhausting the melted plastic, a constant bore, and a first conveyor rotating within the bore, the first conveyor having a constant lead, and including a feeding section for feeding the feed stock material, a melting section for melting the feed stock material and a metering section for metering the melted feed stock material, the feed section having a deep root that extends for at least fifty percent (50%) of the overall length between the inlet and the outlet, the metering section having a shallow root, and the melting section having a progressive enlargement of the root from that of the feed section to that of the metering section, the length of the melting section being approximately one lead of the conveyor, the second extruder comprising an inlet for receipt of the melted plastic from the outlet of the first extruder, an outlet for exhausting the melted plastic, a constant bore, and a second conveyor, the second conveyor including a progressively decreasing lead along its entire length, the first and second extruder adapted to limit the mixing and vortex of the melted plastic during the extrusion process.

Claim 16

Independent Claim 293 words

An apparatus for forming an extruded product from a mixed, contaminated, post-consumer and/or industrial plastic waste, the apparatus comprising: an extruding portion having a first extruder and a second extruder, and a forming portion located at the discharge end of the extruding portion, the first extruder adapted to receive a particulate plastic feed stock material and to melt the plastic particulate, the second extruder adapted for receipt of the melted plastic from the first extruder, for compressing and conveying the melted plastic and for extruding the plastic into the forming means, the first extruder comprising an inlet for receipt of the plastic waste particulate, an outlet for exhausting the melted plastic, a constant bore, and a first conveyor rotating within the bore, the first conveyor having a constant lead, and including a feeding section for feeding the feed stock material, a melting section for melting the feed stock material and a metering section for metering the melted feed stock material, the feed section having a deep root that extends for at least fifty percent (50%) of the overall length between the inlet and the outlet, the metering section having a shallow root, and the melting section having a progressive enlargement of the root from that of the feed section to that of the metering section, the length of the melting section being approximately one lead of the conveyor, the second extruder comprising an inlet for receipt of the melted plastic from the outlet of the first extruder, an outlet for exhausting the melted plastic, a constant bore, and a second conveyor, the second conveyor including a progressively decreasing lead along its entire length, the first and second extruder adapted to limit the mixing and vortex of the melted plastic during the extrusion process.

Claim 17

Dependent Claim 17 words

The apparatus of claim 12 wherein the second conveyor includes a substantially constant root along its length.

Claim 18

Dependent Claim 39 words

The apparatus of claim 12 wherein the outlet of the first extruder is positioned adjacent the inlet for the second extruder such that the flow of melted plastic between the first and second extruders is exposed to ambient pressure.

Claim 19

Dependent Claim 18 words

The apparatus of claim 14 wherein the second conveyor includes a constant root along substantially its entire length.

Claim 20

Dependent Claim 23 words

The apparatus of claim 15 wherein the constant root extends for at least eighty percent (80%) of the length of the second conveyor.

Claim 21

Dependent Claim 30 words

The apparatus of claim 15 wherein the first and second extruders are each driven by separate drive means each capable of rotating the first and second conveyors at different speeds.

Claim 22

Dependent Claim 19 words

The apparatus of claim 15 wherein the first and second extruders are each unvented along substantially their entire length.

Claim 23

Dependent Claim 39 words

The apparatus of claim 12 further comprising means for introducing fiber rovings into the extruded profile of the melted plastic, the fiber introduction means positioning the rovings parallel and juxtaposed to at least one surface of the extruded product.

Claim 24

Dependent Claim 31 words

The apparatus of claim 19 wherein the fiber roving introduction means introduces the fiber rovings at a position approximately 0.020 inches from the surfaces of the extruded profile of the product.

Claim 25

Independent Claim 103 words

A method of making a thin profile extruded product from a commingled plastic waste feed stock, comprising the steps of: feeding a particulate commingled plastic waste feed stock; extruding the particulate through a first extruder and melting the particulate by compaction and compression within the first extruder; extruding the particulate substantially without mixing or vortexing the melted plastic through a second extruder, the melted plastic substantially separating within the second extruder by resin type, extruding the melted plastic extruded within the second extruder through a die to form a thin profile cross-section; introducing fiber rovings into the profile of the extruded plastic melt.

Claim 26

Independent Claim 103 words

A method of making a thin profile extruded product from a commingled plastic waste feed stock, comprising the steps of: feeding a particulate commingled plastic waste feed stock; extruding the particulate through a first extruder and melting the particulate by compaction and compression within the first extruder; extruding the particulate substantially without mixing or vortexing the melted plastic through a second extruder, the melted plastic substantially separating within the second extruder by resin type, extruding the melted plastic extruded within the second extruder through a die to form a thin profile cross-section; introducing fiber rovings into the profile of the extruded plastic melt.

Claim 27

Dependent Claim 26 words

The method of claim 21 wherein the first rovings are introduced parallel to at least two opposing surfaces of the extruded profile, juxtaposed to the surfaces.

Claim 28

Dependent Claim 21 words

The method of claim 22 wherein the fiber rovings are positioned approximately 0.020 inches from the surfaces of the extruded profile.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1996-08-23	1997-02-22	1997-08-24	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2000-08-23	2001-02-22	2001-08-24	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2004-08-23	2005-02-22	2005-08-24	$7700.00	Window Closed / Lapsed

Method and apparatus for recycling plastic waste into a thin profile, mechanically reinforced board

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