System for making synthetic wood products from recycled materials

• US 5,088,910 A
• Filed: 03/14/1990
• Issued: 02/18/1992
• Est. Priority Date: 03/14/1990
• Status: Expired due to Term

• Current Assignee: Allstate Insurance Company (Allstate Corporation), Bank of Oklahoma NA (BOK Financial Corporation)
• Original Assignee: Advanced Environmental Recycling Technologies, Inc. (CRH PLC)
• Inventors: Brooks, Joe G., Goforth, Billy D., Goforth, Charles L.
• Primary Examiner(s): Thurlow, Jeffery
• Assistant Examiner(s): Vargot, Mathieu
• Application Number:
  US07/491,061
• Time in Patent Office: 706 Days
• Field of Search: 264/109, 264/117, 264/118, 264/122, 264/145, 264/148, 264/40.1, 264/40.2, 264/176.1, 264/177.2, 264/210.1, 264/DIG. 69, 425/296, 425/297, 425/131.1, 425/202, 425/142, 425/164, 425/205, 425/208, 425/312, 425/308, 425/377, 425/404, 425/403.1, 425/204, 425/DIG. 46, 83/158, 83/161, 83/289, 83/291, 83/292, 83/293
• US Class Current: 425/142
• CPC Class Codes: B29B 17/0026 by agglomeration or compacting
• CPC Class Codes: B29C 48/00 Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor extrusion blow-moulding B29C49/04
• CPC Class Codes: B29C 48/022 characterised by the choice of material
• CPC Class Codes: B29C 48/03 characterised by the shape of the extruded material at extrusion
• CPC Class Codes: B29C 48/2886 of fibrous, filamentary or filling materials, e.g. thin fibrous reinforcements or fillers
• CPC Class Codes: B29C 70/14 oriented
• CPC Class Codes: B29C 70/58 comprising fillers only , e.g. particles, powder, beads, flakes, spheres B29C70/025 takes precedence, agglomerating hollow spheres to produce synthetic foam B29C70/66; compounding ingredients per se C08K
• CPC Class Codes: B29K 2023/0633 LDPE, i.e. low density polyethylene
• CPC Class Codes: B29K 2105/06 containing reinforcements, fillers or inserts
• CPC Class Codes: B29K 2105/12 of short lengths, e.g. chopped filaments, staple fibres or bristles
• CPC Class Codes: B29K 2105/16 Fillers
• CPC Class Codes: B29K 2105/26 Scrap or recycled material
• CPC Class Codes: B29K 2711/14 Wood, e.g. woodboard or fibreboard
• CPC Class Codes: Y02W 30/62 Plastics recycling; Rubber recycling
• CPC Class Codes: Y10S 264/914 From cellulose containing articles, e.g. paper
• CPC Class Codes: Y10S 264/92 by extruding material recycled from consumer used article or product
• CPC Class Codes: Y10S 425/046 Scrap
• CPC Class Codes: Y10T 83/4664 With photo-electric work-sensing means

Abstract

A system for making synthetic wood products from waste wood fiber and recycled plastic material by mixing waste wood fiber having a moisture content of less than about 15% with dry waste plastic material, including low density and/or high density polyethylene; heating and kneading the mixture to form a homogeneous mass; sizing the mass into discrete chunks suitable for use as an extruder feed material; extruding the material to form products having predetermined cross sections; and rolling and cooling the product to prevent deformation of the product shape.

Claims

1. A system for making dimensionally stable and moisture resistant synthetic wood products from recycled materials comprising:

means for removing contaminants from wood fiber materials and for conveying the decontaminated wood fiber material to

means for processing the decontaminated wood fiber material to yield wood fiber particles having a maximum diameter size of about one-eighth inch;

means for conveying the wood fiber particles to a holding container;

means for weighting plastic material and the wood fiber particles to achieve a predetermined mix ratio and to produce a plastic/wood mix;

means to convey the plastic/wood mix to

means for heating, kneading and further mixing the plastic/wood mix to a temperature high enough to melt the plastic material and encapsulate the wood fiber particles within the melted plastic material so that moisture absorption by the wood fiber is reduced and to form a substantially homogeneous mass;

means to produce a plurality of relatively small, relatively uniformly sized potions of extruder feed from the substantially homogeneous mass;

a compounding extruder adapted to receive the extruder feed and to extrude the feed through a predetermined die to form a product having a predetermined configuration;

means for receiving the product from the extruder and means for periodically moving a cutting means with and at the same speed as the product for cutting the product into pieces of predetermined lengths while the product is continuously flowing from the extruder so that an upstream side of the product is not rammed into the means for cutting.

2. The system of claim 1 further including means to maintain the predetermined product configuration of the pieces while minimizing compression as the pieces cool to ambient and a conveyor to convey the pieces from the extruder to a desired location.

3. The system of claim 2 further including means to change the direction of movement of the conveyor as the pieces cool on the conveyor.

4. The system of claim 2 wherein the means to maintain the predetermined product configuration includes a first plurality of rollers having knurled surfaces and positioned above and contacting top surfaces of product pieces as the pieces are conveyed and a second plurality of rollers having knurled surfaces and positioned below and contacting bottom surfaces of product pieces as the pieces are conveyed such that the knurled surfaces of the first and second plurality of rollers contact the surfaces of the product pieces to maintain the product configuration while exerting minimum pressure thereon.