Process for manufacturing hollow plastic bodies
View Patent ↗Process for manufacturing hollow plastic bodies, especially motor-vehicle fuel tanks, from an extruded parison of closed cross section, in which at least one cut is made in the parison which is then formed by moulding.
1. A process for manufacturing a hollow body using a mould, comprising the steps of:
incorporating at least one of an accessory or a duct within the hollow body;
after said step of incorporating, closing said mould in a way which eliminates any interface between said at least one of said accessory or said duct and an external atmosphere outside of the hollow body;
wherein said at least one of said accessory or said duct is supported by a preassembled structure which comprises at least one device configured to anchor said preassembled structure to an internal wall of the hollow body.
2. A process for manufacturing a hollow body according to claim 1 , wherein said device includes tabs and said process further comprises a step of welding said tabs to said internal wall.
3. A process for manufacturing a hollow body according to claim 2 , wherein said tabs are supported by an arm.
4. A process for manufacturing a hollow body according to claim 1 , further comprising positioning a fastener on the preassembled structure, said fastener being configured to fasten an accessory at a later time.
5. A process for manufacturing a hollow body according to claim 1 , further comprising positioning the preassembled structure precisely in the hollow body with means for positioning.
6. A process for manufacturing a hollow body according to claim 1 , wherein the hollow body is made of plastic.
7. A process for manufacturing a hollow body according to claim 1 , wherein the hollow body is a multilayered structure made of stacked layers.
8. A process for manufacturing a hollow body according to claim 7 , wherein said stacked layers include a central layer of EVOH surrounded by two layers of adhesive.
9. A process for manufacturing a hollow body according to claim 8 , wherein said adhesive is made of maleic-anydride-grafted PE.
10. A process for manufacturing a hollow body according to claim 9 , wherein said stacked layers further include external layers of HDPE.
11. A process for manufacturing a hollow body according to claim 7 , wherein said multilayered structure was obtained by coextrusion.
12. A process for manufacturing a hollow body according to claim 1 , wherein the hollow body is a fuel tank.
13. A process for manufacturing a hollow body according to claim 1 , comprising a step of incorporating said accessory within said hollow body and wherein said accessory is supported by said preassembled structure.
14. A process for manufacturing a hollow body according to claim 1 , comprising a step of incorporating said duct within said hollow body, and wherein said duct is supported by said preassembled structure.