Process for making a luggage shell from self-reinforced thermo-plastic material

Abstract

Process of making a plastic component (1), in particular luggage shell, from self-reinforced thermoplastic material, to a plastic component (1) made of self-reinforced thermoplastic material and an apparatus for making such a plastic component, in particular luggage shell (7). The invention provides a new product and process for manufacturing same on the basis of self-reinforced thermoplastic material by means of the step of tensioning said material (lamina), at least partially tensioning said lamina during all follow-up component shaping and/or molding steps up to a release of a component pre-form shape from the remainder lamina, to form the component. The present invention allow the manufacturing of an ultra-light weight luggage shell (7) on the basis of using self-reinforced thermoplastic material, the manufacturing of same can be further enhanced by permanently tensioning said material during all manufacturing steps up to the final finishing of the product.

1 . A luggage shell for a luggage case, having a base wall and upstanding sidewalls and at least one corner region, the luggage shell comprising a thermoplastic material selected from a self-reinforcing thermoplastic resin of oriented pre-tensioned strands surrounded by a matrix of substantially similar thermoplastic material which is generally not oriented, the luggage shell having a nominal thickness of between about 1 mm and about 2.5 mm, wherein the luggage shell has a three dimensional stiffening pattern impressed into an outer main shell face of the base wall so that the base wall has a repeating pattern of convex and concave shapes molded thereinto, the overall thickness of the base wall being substantially consistent among the convex shapes, the concave shapes and the rest of the base wall. 
     
     
         2 . The luggage shell according to  claim 1 , wherein the sidewalls have a depth dimension and the base wall has a generally rectangular wall shape having a length and width dimension, with the width being no wider than the length dimension, the ratio of the depth dimension to the width dimension being between about 0.1 and about 0.5. 
     
     
         3 . The luggage shell according to  claim 2 , wherein a ratio of length to width dimension is between 1 and about 2. 
     
     
         4 . The luggage shell according to  claim 3 , wherein a ratio of length to width dimension is between about 1 and about 1.40. 
     
     
         5 . The luggage shell according to  claim 1 , wherein a radius of curvature of the luggage shell in a corner region is about 80 mm or smaller, in particular in the corner region connecting adjacent sidewalls. 
     
     
         6 . The luggage shell according to  claim 1 , wherein the thermoplastic material is selected from a group consisting of polypropylene, polyethylene, a semi-crystalline polymer and combinations thereof. 
     
     
         7 . The luggage shell according to  claim 1 , wherein the thermoplastic material has an overall thickness of no more than about 2 mm and has no more than about 20 layers of molecularly oriented filaments. 
     
     
         8 . The luggage shell according to  claim 1 , wherein the thermoplastic material has at least one layer of polypropylene in the form of molecularly oriented filaments and at least one layer of substantially unoriented polypropylene. 
     
     
         9 . The luggage shell according to  claim 1 , wherein the thermoplastic material has at least one layer of polyethylene in the form of molecularly oriented filaments and at least one layer of substantially unoriented polyethylene. 
     
     
         10 . The luggage shell according to  claim 1 , wherein the thermoplastic material has at least one layer of high-density polyethylene in the form of molecularly oriented filaments and at least one layer of polyethylene having a lower density. 
     
     
         11 . The luggage shell according to  claim 1 , wherein the self-reinforced thermoplastic material comprises a substantially monolithic structure. 
     
     
         12 . The luggage shell according to  claim 1 , wherein the self-reinforced thermoplastic material comprises oriented strands of different orientation and said thermoplastic material comprises multiple layers of molecularly oriented filaments with filaments of different, in particular neighboring layers, being disposed angled or crosswise. 
     
     
         13 . The luggage shell according to  claim 1 , wherein the thermoplastic material is laminated with a fabric, in particular woven or melted fabric, preferably forming a lining. 
     
     
         14 . The luggage shell according to  claim 1 , wherein a centerline of a wall thickness along a cross section perpendicular to the longitudinal dimension of the convex and concave shapes shows troughs corresponding to the convex shapes and ridges corresponding to the concave shapes, said troughs and ridges interconnected by upstanding walls forming an angle to the main wall approximately equal to a draft angle.