Method of producing a metal mold

A method of producing a metal mold, comprising the steps of:

• forming a casting space by integrally assembling a pair of frames;
• dividing said casting space by means of a heat resistant and resilient rubber sheet having an even thickness corresponding to the plate thickness of a product, wherein said sheet is clamped between said pair of casting frames to form two casting chambers;
• accommodating a matrix in one of said casting chambers;
• pouring a melt of a low melting-point alloy into the other casting chamber and bringing together by use of negative pressure said heat resistant and resilient rubber sheet and said product configuration surface of said matrix, thereby casting a first part of a mold, wherein said sheet stretches and shrinks freely to maintain said even thickness between said casting chambers;
• removing said matrix from said one casting chamber;
• pouring said melt of a low melting-point alloy into said one casting chamber while maintaining close contact between said heat resistant and resilient rubber sheet and said first part of said mold, thereby casting a second part of said mold.

A method of producing a metal mold, comprising the steps of:

• forming a casting space by integrally assembling a die casting frame and a punch casting frame;
• dividing said casting space into two parts by means of a heat resistant and resilient rubber sheet clamped between said casting frames, said sheet having an even thickness corresponding to the plate thickness of a product;
• accommodating a matrix for a punch and a matrix for a blank holder inside said punch casting frame;
• pouring a metal of a low melting-point alloy into said die casting frame and bringing together by use of negative pressure said heat resistant and resilient rubber sheet and one of said product configuration surfaces of one of said matrices, thereby casting a die, wherein said sheet stretches and shrinks freely to maintain said even thickness between said casting frames;
• removing said one of said matrices from said punch casting frame;
• pouring said melt of a low melting-point alloy into said punch casting frame with either one of said matrices removed while maintaining contact between said rubber sheet and said die, thereby casting either said punch or said blank holder;
• removing the remaining one of said matrices;
• and
• pouring said melt of a low melting-point alloy into said punch casting frame with said remaining one of said matrices removed while maintaining contact between said rubber sheet and said die, thereby casting the other one of said punch and said blank holder.

A method of producing a metal mold, comprising the steps of:

• forming a casting space by integrally assembling a die casting frame and a punch casting frame;
• dividing said casting space into two parts by means of a heat resistant and resilient rubber sheet clamped between said casting frames, said sheet having an even thickness corresponding to the plate thickness of a product;
• accommodating a matrix for a punch inside said punch casting frame;
• casting the die by pouring a melt of a low melting-point alloy into said die casting frame while bringing together by use of negative pressure said heat resistant and resilient rubber sheet and said product configuration surfaces of said matrix, wherein said sheet stretches and shrinks freely to maintain said even thickness between said casting frames;
• removing the matrix from the punch casting frames;
• providing the punch profile formed of a steel sheet by imitating the contour of the punch and having plural holes in the punch;
• and subsequently
• pouring the melt of a low melting-point alloy into the punch casting frame with maintaining close contact between the rubber sheet and the die, thereby casting simultaneously the punch and the blank holder.