Process to manufacture tubular articles resembling wood, cane, bamboo, reed, wicker, rattan, rush, and the like
OwnerHumberto Trejo Gonzalezinventor
Life of this patent
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Abstract
This invention relates to the production of tubular articles, made from synthetic thermoplastic materials, which resemble wood, rattan, bamboo, cane, reed, wicker, reed, rush, and similar natural materials, and also to the production of furniture, structures, and every kind of ornament in general employing thermoplastic materials which replace the natural materials mentioned above, coloring and veining such thermoplastic materials, and also joining and securing by means of ties made from rigid, semi-rigid or plastified polyvinyl the natural and artificial materials above mentioned, for the purpose of assembling furniture and structures in general.
Claims22
A method for producing artificial, tied tubular structures, the tying and the tubular portions of which have the appearance of natural materials, comprising the steps of:
- extruding a thermoplastic tubular material having base coloring,
- separately extruding tying strips of basically colored thermoplastic material with striations formation on the surfaces thereof, longitudinally orienting the molecules of the material as it is being extruded whereby a molecular memory is imposed thereon,
- applying coloring to said strips of thermoplastic material by treating it with a solvent that at least partially disssolves said material, said solvent material having powdered polyvinyl chloride and a pigmenting material dispersed in it, whereby said thermoplastic material is made to resemble natural materials,
- heating preselected portions of the extruded tube after it leaves the extruding die and applying pressure to the heated portion to deform it so that the tube has deformed portions alternating with non-deformed portions,
- forming annular incisions in the hot deformed portions and peripheral striations as well as longitudinal incisions perpendicular to the said annular incisions, and then cooling the tube,
- applying to the surface of the tube a solvent for the material of the tube,
- pigmenting the extruded tube with pigment dispersed in the said solvent that has thermoplastic material dissolved in it so that the pigment will simulate veins on the surface of the tubular material,
- allowing the pigmented alternatively deformed tubular material to air-dry,
- cutting the tubular material processed by the foregoing steps into desired lengths,
- heating it at selected points to bend tubular lengths as may be required, and letting it cool;
- attaching connecting means to the ends of said cooled tubular portions, and
- tying together the cut tubular material by means of said strips of colored thermoplastic material after connecting them in such manner as to produce structural portions of furniture, ornaments, and structures in general made of natural looking materials such as wood, rattan, cane, reed, rush, bamboo, wicker and the like, the said strips becoming tightened when their oriented molecules recover their original position.
The method according to claim 4 in which the heated portions are subjected to suction applied to the outside surface, so that the atmospheric pressure will deform said portions into protuberance shapes.
A method of forming a knot in an extruded tube comprising the steps of:
- (a) extruding a thermoplastic material through a die, said die being incorporated in a travelling mold and having an elongated central portion accommodating two pulley wheels separated by a distance shorter than the length of the cavity,
- (b) feeding air through an air duct of the die, expelling said air through an air exit situated between said two pulleys wheels inside the extruded tube at a recessed cavity of the travelling mold when said mold travels at a speed adjusted to coincide with that of the tube as it is being extruded so that when the traveling mold is below the tube, it closes whereby said fed air causes the still hot extruded tube to adopt the shape of a knot by pressing it against said recessed cavity, and
- (c) simultaneously circulating cooling water through the travelling mold whereupon the extruded tube becomes rigid and the mold is open, leaving a nodal portion on the cooled tube.
A two piece travelling mold wherein the two pieces are essentially symmetrical and hinged by the lower edge of their inner surfaces, having each of them a lengthwise cavity along their mid-portion, and at their center of the cavity length there is an irregular deeper recessed cavity, said lengthwise cavity forming a molding duct when the mold hinged pieces rotate about their hinge so that their inner surfaces come together to close the mold.
Dependencies are inferred from the claim text.