Die-casting die

Abstract

A die-casting die capable of obtaining stable, high-quality die-casting products by reducing clogging is disclosed. The die-casting die for casting die-casting products by pressure filling molten metal into a cavity, comprises a fixed die; a moving die for forming a cavity at contacting surfaces of the fixed die and the moving die, the moving die being capable of approaching and separating from the fixed die; an overflow formed on at least either the fixed die or the moving die to communicate through an overflow gate with the cavity; a porous gas-permeable member, through which gas can pass without allowing molten metal in the overflow to pass, disposed on at least either the fixed die or the moving die so as to communicate with the overflow; and an exhaust path, one end of which communicates with the surface on the side of the gas-permeable member opposite that of the overflow, and the other end of which communicates with the outside of the fixed die or the moving die.

1 . A die-casting die for casting die-casting products by pressure filling molten metal into a cavity, comprising:
 a fixed die;   a moving die for forming a cavity at contacting surfaces of the fixed die and the moving die, said moving die being capable of approaching and separating from the fixed die;   an overflow formed on at least either the fixed die or the moving die to communicate through an overflow gate with the cavity;   a porous gas-permeable member, through which gas can pass without allowing molten metal in the overflow to pass, disposed on at least either the fixed die or the moving die so as to communicate with the overflow; and   an exhaust path, one end of which communicates with the surface on the side of the gas-permeable member opposite that of the overflow, and the other end of which communicates with the outside of the fixed die or the moving die.   
     
     
         2 . The die-casting die according to  claims 1 , wherein the gas-permeable member has a flow path surface area contacting the molten metal, the flow path surface area being provided so that the average flow rate of gas flowing through the gas-permeable member is 0.2-1.0 m/sec. 
     
     
         3 . The die-casting die according to  claim 1 , wherein the gas-permeable member has a flow path surface area contacting the molten metal, and the flow path surface area is provided so that the average flow rate of gas flowing through the gas-permeable member is 0.05-0.2 m/sec, and the die-casting die further comprises a gas vent mechanism, disposed to communicate with the overflow, for exhausting gas directly to the outside without going through the gas-permeable member. 
     
     
         4 . The die-casting die according to  claim 1 , wherein the gas-permeable member contains a fiber reinforced metal compound material or a metal powder sintered body. 
     
     
         5 . The die-casting die according to  claim 1 , wherein the gas-permeable member has an average pore diameter thereof which is 3-30 μm. 
     
     
         6 . The die-casting die according to  claim 1 , wherein a plurality of gas-permeable members are provided. 
     
     
         7 . The die-casting die according to  claim 1 , wherein at least one of the exhaust path is provided for one of the gas-permeable member. 
     
     
         8 . The die-casting die according to  claim 1 , wherein, the die-casting die further comprises at least one push-out pin on the overflow for parting the die-casting product from the fixed die and the moving die. 
     
     
         9 . The die-casting die according to  claim 1 , wherein the molten metal is aluminum alloy.