RU97102105A - MULTILAYERED VESSELS - Google Patents

Claims (22)

1. A multilayer preformed blank for blow molding a vessel, comprising an extruded covering inner layer (20) that forms a cavity including an upper part (14, 16) having a first thickness and adapted to be molded into the upper part of the vessel; an intermediate part (14, 16) of the side wall having a second thickness greater than the first thickness, wherein in the workpiece, the intermediate part is substantially adjacent to the upper part and adapted to be molded into the intermediate part of the side wall of the vessel; and a bottom part (18) having a third thickness greater than the second thickness, wherein the bottom part is substantially adjacent to the intermediate part and adapted to be molded into the bottom of the vessel; and an external injection molded layer (24) arranged substantially as adjacent to the inner layer; in which there is an open top and in which the upper part extends to the open top of the preformed workpiece, and the intermediate part is elongated, while the predominantly vertical part of the side wall extends from the upper part to the bottom.  2. The workpiece according to claim 1, characterized in that an extruded material barrier layer (22) is located therein located between the inner and outer layers, the barrier layer being extruded together with the inner layer.  3. The workpiece according to claim 1, characterized in that its inner and outer layers have upper edges (28, 32), and the upper edge of the inner layer overlaps the upper edge of the outer layer.  4. The workpiece according to claim 3, characterized in that its upper edge of the inner layer (28) is elongated essentially across the parts containing the inner layer and over the upper edge (32) of the outer layer.  5. The workpiece according to claim 1, characterized in that its outer layer (24) is formed from recycled plastic, and the inner layer (20) is formed from polyethylene terephthalate.  6. The workpiece according to claim 1, characterized in that a barrier layer (22) of ethylene vinyl alcohol copolymers is introduced therein.  7. The workpiece according to claim 1, characterized in that its outer, obtained by injection molding layer (24) contains a threaded upper part (12), surrounding the upper part of the inner layer.  8. The workpiece according to claim 1, characterized in that its outer layer (24) has an essentially constant thickness in the region of the fit of the side wall of the inner layer and the bottom.  9. A method for manufacturing a multilayer preformed billet characterized by length and thickness, differentiated in length, comprising the step of preparing an extrusion tool (33) provided with a means (38) for setting the material thickness; the step of extruding a preformed liner (37) having at least an inner layer (20) of material by means of an extrusion tool; the stage of changing the thickness of the inner layer along the length of the preformed liner, mainly during the extrusion stage, using means for setting the thickness; and a step of injection molding the outer layer (24) of the material surrounding the inner layer.  10. The method according to claim 9, characterized in that it further includes the step of bringing the configuration of the preformed liner (37) to the configuration of the preformed blank by means of a pneumatic molding machine (52).  11. The method according to claim 9, characterized in that the stage of extrusion further includes the stage of co-extrusion of the barrier layer (22) of the material surrounding the inner layer (20).  12. The method according to claim 9, characterized in that the preformed liner has a first end and a side surface, and the method further includes the step of forming a protrusion (28) at the first end, while the protrusion extends beyond the side surface of the liner.  13. The method according to p. 12, characterized in that it contains an additional molding step, including extruding the ribs (48) on the side surface of the inner liner, which extends beyond the side surface of the preformed liner; and cutting the preformed liner along the rib to form a protrusion at the first end of the preformed liner.  14. The method according to p. 13, characterized in that the outer layer has a top edge, and there is an additional step of introducing a preformed liner into the mold (56) for injection molding and the stage of injection molding, including casting the outer layer of material (24), fitting a preformed liner in such a way that the upper edge is substantially adjacent to the first end and the protrusion extends over the upper edge.  15. The method according to claim 9, characterized in that the inner layer (20) of the preformed liner consists of an upper part (12), an intermediate part (14, 16) and a bottom part (18), and the regulation step further comprises a step for adjusting the means (38) to set the thickness of the material to obtain the first size of the upper part; the step of adjusting the means (38) for setting the thickness of the material to obtain a second size of the intermediate part, the second size being larger in thickness than the first size; and a step of adjusting the means (38) for setting the thickness of the material to obtain a third size of the bottom, the third size being thicker than the second size.  16. A multilayer vessel containing the upper part (60) of the shell formed of at least an inner extruded layer (68) and an outer layer (72) of injection molded material, in which the inner layer of material has a first thickness in the upper part of the shell; an intermediate part (62, 64) of the side wall formed of at least extruded inner (68) and the outer layer (72) of injection molded material, in which the inner layer of the side wall part has a second thickness in the intermediate part of the side wall less than than the first thickness in the upper part of the shell, and the intermediate part of the side wall is located directly under the upper part of the shell; and a bottom part (66) of the legged shell formed from at least an extruded inner layer (68) and an outer layer (72) of injection molded material in which the inner material layer has a third thickness in this part of the shell that is larger than the second thickness in the intermediate part of the side wall, while the bottom of the shell is located directly below the intermediate part of the side wall and is adapted to serve as a support for the vessel.  17. A vessel according to claim 16, characterized in that a barrier layer (72) of material in the form of copolymers of ethylene and vinyl alcohol is introduced into it.  18. A vessel according to claim 16, characterized in that the inner layer (68) of the material is formed from polyethylene terephthalate, and the outer layer (72) is formed from recycled plastic.  19. A vessel according to claim 16, characterized in that it further comprises a barrier layer (70) located between the inner (68) and outer (72) layers.  20. The vessel according to claim 19, characterized in that the barrier layer (70) is formed by extrusion.  21. The workpiece according to claim 1, characterized in that the extruded inner layer (20) contains polyethylene naphthalate.  22. A vessel according to claim 16, characterized in that the inner layer (70) contains polyethylene naphthalate.