Molding metal mold and method for producing the molding metal mold

Abstract

The present invention aims to provide a molding metal mold capable of increasing the supporting rigidity of an insert. A molding metal mold is provided for forming a cavity between a first metal mold and a second metal mold and for molding a product the cavity, wherein the first metal mold includes: an insert having a part of a cavity surface on one end side; a body member for externally holding the insert; and a plurality of spherical bodies interposed between the insert and the body member and performing alignment of the insert, the plurality of spherical bodies being closely filled between the insert and the body member.

1 . A molding metal mold for forming a cavity between a first metal mold and a second metal mold and for molding a product the cavity, wherein the first metal mold comprises: 
 an insert having a part of a cavity surface on one end side;    a body member for externally holding the insert; and    a plurality of spherical bodies interposed between the insert and the body member and performing alignment of the insert, the plurality of spherical bodies being closely filled between the insert and the body member.    
     
     
         2 . A molding metal mold as claimed in  claim 1 , wherein the plurality of spherical bodies are filled between the insert and the body member, while being applied with preload.  
     
     
         3 . A molding metal mold as claimed in  claim 1 , wherein: 
 the insert comprises a column portion having the partial cavity surface;    the body member comprises: 
 a small hole portion opening in one end portion of the body member and fitting with one end side of the column portion;  
 a large hole portion opening in other end portion of the body member, linking with other end portion of the small hole portion, and freely fitting with other end portion of the column portion; and  
   the plurality of spherical bodies are closely filled between an external circumference surface of the column portion and an internal circumference surface of the large hole portion.    
     
     
         4 . A molding metal mold as claimed in  claim 3 , wherein the plurality of spherical bodies are filled between the external circumference surface of the column portion and the internal circumference surface of the large hole portion, while being applied with preload.  
     
     
         5 . A molding metal mold as claimed in  claim 1 , wherein the second metal mold comprises: 
 a second insert having a part of a cavity surface on one end side;    a second body member for externally holding the insert; and    a plurality of second spherical bodies interposed between the second insert and the second body member and performing alignment of the insert, the plurality of second spherical bodies being closely filled between the second insert and the second body member.    
     
     
         6 . A molding metal mold as claimed in  claim 1 , wherein at least one of the first and second metal molds comprises an extrusion pin provided protrudably from the cavity surface of the at least one of the first and second metal molds.  
     
     
         7 . A molding metal mold as claimed in  claim 1 , wherein: 
 the insert comprises: 
 a columnar small diameter portion having one end side and other end side, and having, on the one end side, the partial cavity surface; and  
 a columnar large diameter portion coaxially connected to the other end side of the columnar small diameter portion;  
   the body member comprises: 
 a small hole portion having an aperture for exposing the cavity surface on the one end side of the columnar small diameter portion, and fitting with the columnar small diameter portion; and  
 a large hole portion having an aperture which the other end side of the columnar small diameter portion can be inserted to and uninserted from, linking with the columnar small hole portion, and freely fitting with the columnar large diameter portion;  
   when the molds are clamped, a surface extending between the columnar small diameter portion and the columnar large diameter portion abuts with a part of a surface extending between the small hole portion and the large hole portion; and    the plurality of spherical bodies are closely filled between: 
 an external circumference surface of the columnar large diameter portion;  
 an internal circumference surface of the large hole portion; and  
 a surface extending between the small and large hole portions, excluding a portion of a surface extending between the columnar small and large diameter portions.  
   
     
     
         8 . A molding metal mold as claimed in  claim 7 , wherein at least one of the first and second metal molds comprises an extrusion pin provided protrudably from the cavity surface of the at least one of the first and second metal molds.  
     
     
         9 . A molding metal mold as claimed in  claim 7 , wherein the plurality of spherical bodies are filled between the insert and the body member, while being applied with preload.  
     
     
         10 . A molding metal mold as claimed in  claim 1 , wherein the plurality of spherical bodies are made up of neighboring spherical bodies contacting to each other.  
     
     
         11 . A molding metal mold as claimed in  claim 1 , wherein the molding metal mold further comprises an electric heater built inside the body member, for heating and thermally expanding the body member when the filling of the plurality of spherical bodies is carried out.  
     
     
         12 . A molding metal mold as claimed in  claim 1 , wherein the molding metal mold further comprises an electric heating mat wrapped around the body member, for heating and thermally expanding the body member when the filling of the plurality of spherical bodies is carried out.  
     
     
         13 . A molding metal mold as claimed in  claim 1 , wherein the molding metal mold further comprises a temperature adjustment means for increasing the temperature of the body member before the filling of the plurality of spherical bodies is conducted, and decreasing the temperature of the body member after the filling of the plurality of spherical bodies is carried out.  
     
     
         14 . A molding metal mold as claimed in  claim 1 , wherein the molding metal mold further comprises a cooling means for cooling the insert during the filling of the plurality of spherical bodies.  
     
     
         15 . A molding metal mold as claimed in  claim 1 , wherein the molding metal mold further comprises a cooling means for cooling the insert before the filling of the plurality of spherical bodies is carried out.  
     
     
         16 . A molding metal mold as claimed in  claim 1 , wherein the plurality of spherical bodies is arranged in a rectangular lattice shape.  
     
     
         17 . A molding metal mold as claimed in  claim 1 , wherein the plurality of spherical bodies is arranged in a staggering shape.  
     
     
         18 . A molding metal mold as claimed in  claim 1 , wherein the closely filled plurality of spherical bodies has a filling rate not less than 20%.  
     
     
         19 . A molding metal mold as claimed in  claim 1 , wherein the closely filled plurality of spherical bodies has a filling rate of 50 to 60%.  
     
     
         20 . A method of producing a molding metal mold as claimed in  claim 1 , including heating and thermally expanding the body member; and then filling the plurality of spherical bodies between the body member and the insert.