Sports boot in very stiff material

Abstract

Sports boot subassembly of the shell or collar type, which comprises at least two parts, each comprising a flexible plastics material injection-overmolded over a very stiff material partially embedded in the flexible plastics material, and wherein the at least two parts comprise an assembly surface for joining them together.

1 . A process for manufacturing a sports boot subassembly of the shell or collar type, wherein it is obtained by the assembly of several parts, at least two of these parts being obtained by means of the following steps: 
 production of a blank in very stiff material ( 2 );    injection-overmolding of a flexible plastics material ( 3 ) over the very stiff material, linking the very stiff material to the injection-molded flexible plastics material, in order to form part of the sports boot subassembly:    
     
     
         2 . The process for manufacturing a sports boot subassembly of the shell or collar type as claimed in  claim 1 , wherein the step of producing a blank in very stiff material ( 2 ) comprises a step of thermoforming a composite sheet composed of a fiber-reinforced thermoplastic matrix.  
     
     
         3 . The process for manufacturing a sports boot subassembly of the shell or collar type as claimed in  claim 1 , wherein the step of producing a blank in very stiff material ( 2 ) comprises a step of last-molding a fiber-reinforced thermosetting matrix.  
     
     
         4 . The process for manufacturing a sports boot subassembly of the shell or collar type as claimed in  claim 1 , wherein the step of producing a blank in very stiff material ( 2 ) comprises a step of drawing a metal sheet.  
     
     
         5 . The process for manufacturing a sports boot subassembly as claimed  claim 1 , wherein the injection-overmolding step comprises the injection of flexible plastics material on either side of the blank in very stiff material, at least over certain zones of its surface.  
     
     
         6 . The process for manufacturing a sports boot subassembly as claimed in  claim 5 , wherein the injection-overmolding step comprises the injection-molding of flexible plastics material on either side of the blank in very stiff material, at least over certain zones of its periphery.  
     
     
         7 . The process for manufacturing a sports boot subassembly as claimed in  claim 6 , which comprises the step consisting in producing at least one hole in the blank in very stiff material and wherein the injection-molding step comprises the passage of the flexible plastics material through the hole in order to traverse the very stiff material and to produce a fixing between the very stiff material and the flexible plastics material.  
     
     
         8 . The process for manufacturing a sports boot subassembly as claimed in  claim 1 , wherein the injection-overmolding step comprises the injection-molding of a thin layer of flexible plastics material over the inner face of the very stiff material.  
     
     
         9 . The process for manufacturing a sports boot subassembly as claimed in  claim 1 , wherein the injection-overmolding step comprises two successive substeps of injection-molding different flexible plastics materials.  
     
     
         10 . The process for manufacturing a sports boot subassembly as claimed in  claim 9 , wherein one of the injection-molding substeps consists of the injection-molding of a cellular flexible plastics material over the inner face of the very stiff material.  
     
     
         11 . The process for manufacturing a sports boot subassembly as claimed in  claim 1 , wherein the injection-overmolding step comprises the production in flexible plastics material, on each of the at least two parts, of complementary assembly surfaces.  
     
     
         12 . The process for manufacturing a sports boot subassembly as claimed in  claim 11 , wherein the injection-overmolding step comprises the production of a rib in flexible plastics material on the assembly surface.  
     
     
         13 . The process for manufacturing a sports boot subassembly as claimed in  claim 12 , wherein the step of assembling two parts comprises the incorporation of a rib of a first part into a corresponding groove of a second part in order to join the two assembly surfaces of the corresponding parts.  
     
     
         14 . The process for manufacturing a sports boot subassembly as claimed in  claim 1 , wherein the step of assembling two parts comprises the fixing of holding elements on each part on either side of the assembly line.  
     
     
         15 . The process for manufacturing a sports boot subassembly as claimed  claim 1 , wherein a decorative element is arranged on the blank in very stiff material and wherein said decorative element is covered by an injection-overmolded transparent flexible plastics material.  
     
     
         16 . A sports boot subassembly of the shell or collar type, which comprises at least two parts, each comprising a flexible plastics material and a very stiff material partially embedded in the flexible plastics material, and wherein the at least two parts comprise an assembly surface for fixing them together.  
     
     
         17 . The sports boot subassembly as claimed in  claim 16 , wherein the very stiff material occupies at least half the total surface area of the wall of the subassembly.  
     
     
         18 . The sports boot subassembly as claimed in  claim 16 , wherein the flexible plastics material at least partially covers the two inner and outer surfaces of the periphery of the very stiff material.  
     
     
         19 . The sports boot subassembly as claimed in  claim 18 , wherein the very stiff material has at least one hole filled by the flexible plastics material.  
     
     
         20 . The sports boot subassembly as claimed in  claim 16 , wherein the very stiff material has a part of its outer surface not covered by flexible plastics material.  
     
     
         21 . The sports boot subassembly as claimed in  claim 16 , which comprises a part of the surface of its wall that comprises only flexible plastics material.  
     
     
         22 . The sports boot subassembly as claimed in  claim 16 , which comprises a decoration arranged on the outer surface of the very stiff material and at least partially covered by the transparent flexible plastics material.  
     
     
         23 . The sports boot subassembly as claimed in  claim 16 , wherein the very stiff material has reinforcement ribs on its outer face.  
     
     
         24 . The sports boot subassembly as claimed in  claim 16 , wherein the very stiff material is a fiber-reinforced plastics material or a metallic material.  
     
     
         25 . A ski boot shell as claimed in  claim 16 , which comprises two parts, wherein the flexible plastics material forms two flaps in its top part and wherein the inner surface of the shell is covered at least by a thin layer of flexible plastics material serving as thermal insulation.  
     
     
         26 . The ski boot shell as claimed in  claim 25 , wherein the flexible plastics material forms reinforcements on the outer surface of the wall.  
     
     
         27 . A ski boot, comprising a subassembly as claimed in  claim 16.