Structure of parts made from plural composite pieces and method of building those parts

Abstract

A pre-mold part is formed by pre-molding the insert part composed of composite materials composed of metal, ceramic, resin or any combination of those materials with the pre-mold part composed of thermo plastic resin having crystallinity, and then, the pre-mold part is inserted into the over-mold part composed of thermo plastic resin. After applying the heat treatment with the temperature lower than the crystalline melting point of the pre-mold part to the pre-mold part surrounding the insert part formed as the composite mold part surrounding the pre-mold part, the insert molding is completed finally. Mold parts having high-reliable insert parts enable to establish firm contact between the insert part and the resin surrounding the insert part without no gap at the interface between those parts can be obtained by a low-cost production method.

1 . A composite mold part formed by forming a pre-mold part by pre-molding an insert part composed of a composite material composed of metal, ceramic, resin or a combination of those materials with a pre-mold part composed of thermo plastic resin having crystallinity, and by inserting said pre-mold part into an over-mold part composed of thermo plastic resin and surrounding said pre-mod part with an over-mold part, wherein 
 an insert molding process is applied to an pre-mold part surrounding said pre-mold part to be inserted after applying heat treatment with a temperature lower than a crystalline melting point of said pre-mold part.    
     
     
         2 . A composite mold part of  claim 1 , wherein 
 said composite material is one or more metallic terminal to be used for electrical connection.    
     
     
         3 . A composite mold part of  claim 1 , comprising plural pre-mold parts, wherein 
 said insert part is inserted into said plural pre-mold parts, and molded together with an over-mold part.    
     
     
         4 . A composite mold part of  claim 1 , comprising 
 plural pre-mold parts, wherein    said plural pre-mold part are overlapped and inserted, and molded together with an over-mold part.    
     
     
         5 . A composite mold part of  claim 1 , wherein 
 said pre-mold part and said over-mold part are composed of a base resin material filled with an identical type of filler.    
     
     
         6 . A composite mold part of  claim 5 , wherein 
 an amount of filler filled in said pr e-mold part is equal to an amount of filler filled in said over-mold part.    
     
     
         7 . A composite mold part of  claim 1 , wherein 
 said pre-mold part and said over-mold part are composed of an identical base material and resin filled with filler, and said pre-mold part is composed of a resin with a filler fraction higher than that of said over-mold part.    
     
     
         8 . A composite mold part of  claim 1 , wherein 
 said pre-mold part and said over-mold part are composed of a different base material and resin filled with filler, and said pre-mold part is composed of a resin with a crystalline melting point higher than that of said over-mold part.    
     
     
         9 . A composite mold part of  claim 1 , wherein 
 said pre-mold part and said over-mold part are composed of an identical base material and resin filled with filler, said pre-mold part is composed of a resin with a crystalline melting point lower than that of said over-mold part, and said resin having a melting point equivalent to or higher than that of said over-mold part so as to have a good fusion characteristic with said over-mold part.    
     
     
         10 . An electronic part wherein 
 a pre-mold part is formed with insert-molding so as to make a contact between said pre-mold part and said insert part by applying a heat treatment with a temperature lower than a crystalline melting point to an insert part including metal in a pre-mold part composed of thermo plastic resin, and    said pre-mold part is inserted into an over-mold part composed of thermo plastic resin.    
     
     
         11 . An electronic part of  claim 10 , wherein 
 a gap generated at an interface between said insert part and said pre-mold part in said pre-mold part is narrower than a gap generated at an interface between said pre-mold part and said over-mold part.    
     
     
         12 . A production method of composite molding part comprising: 
 a step for arranging an insert part at a designate position of a mold die assembly heated at a designated temperature;    a step for molding a pre-mold part by filling a molding resin into said pre-mold die assembly;    a step for applying heat treatment with a temperature lower than crystalline melting point of said molding resin to said pre-mold part; and    a step for arranging said pre-mold part with heat treatment applied at a designated position of a over-mold die assembly heated at a designated temperature, and inserting said pre-mold part with heat treatment applied as an insert part into an over-mold part by filling a mold resin into said over-mold die assembly in order to form a composite mold part.    
     
     
         13 . A production method of composite molding part of  claim 12 , wherein 
 a designated temperature of said pre-mold die assembly or said over-mold die assembly is between 40° C. and 100° C.;    a heater temperature of molding apparatus for filling said mold resin is between 220° C. and 270° C. and selected to be lower than a crystalline melting point from 220° C. to 270° C. of said molding resin before the heat treatment step.    
     
     
         14 . A production method of composite molding part of  claim 12 , wherein 
 after a step for molding a pre-mold part by filling a mold resin into said pre-mold die assembly, said mold resin is cooled and solidified, and after a step for forming said composite mold part by filling a mold resin into said over-mold die assembly, said mold resin is cooled and solidified.