Method and device for executing work consisting of a plurality of steps under computer control

A method of performing design and fabrication of molds using a central processing computer that stores three-dimensional digital data that represents a product shape and a plurality of computer terminal units connected to the central processing computer via communication lines, wherein the method comprises a plurality of work steps sequentially performed in the computer terminal units, wherein said steps comprise:

• (a) a step of calling up three-dimensional digital data describing the product shape from the central processing computer to a first computer terminal unit, performing a three-dimensional display of the product shape on a screen of the first computer terminal unit, determining a partition line between upper and lower mold halves based on said displayed product shape, confirming a partition surface between the upper and lower mold halves along said partition line and mold formation surface shapes of the upper and lower mold halves, respectively, and sending same to the central processing computer where it is saved as digital data;
• (b) a step of calling up three-dimensional digital data describing the product shape including the digital data formed in the first computer terminal unit from the central processing computer to a second computer terminal unit, performing a three-dimensional display of the product shape on a screen of said second computer terminal unit, determining a first location where a slide core is necessary and a slide direction, and, based on a size of the slide core needed at the first location, selecting one from among a plurality of standard slide core blocks of different sizes and shapes that are prepared in advance and thus determining a slide core block to be used, placing this slide core block on the outside of a molding surface in said slide direction, and when the slide core block is placed, drawing slide pockets required for sliding said slide core block in the upper and lower mold halves, respectively, providing the slide core of a shape determined based on the shape of the molding surface at a tip in the slide direction of the slide core, and sending same to the central processing computer where it is saved as digital data;
• (c) a step of calling up three-dimensional digital data describing the product shape including the digital data formed in the second computer terminal unit from the central processing computer to a third computer terminal unit, performing a three-dimensional display of the product shape on a screen of the third computer terminal unit, determining a second location where a loose core is necessary, and, based on a size of the loose core needed at the second location, selecting one from among a plurality of standard core blanks of different sizes and shapes that are prepared in advance and thus determining a core blank to be used, placing this core blank at a stipulated position on the molding surface, determining a shape of a tip of the loose core based on shape data for the molding surface, and sending same to the central processing computer where it is saved as digital data;
• (d) a step of calling up three-dimensional digital data describing the product shape including the digital data formed in the third computer terminal unit from the central processing computer to a fourth computer terminal unit, performing a three-dimensional display of the product shape on a screen of the fourth computer terminal unit, determining a location of an ejector pin, determining a length of the ejector pin from the determined ejector pin location and a molding surface shape, and sending same to the central processing computer where it is saved as digital data;
• (e) a step of calling up various data determined in steps (a) to (d) from the central processing computer, preparing numerical control data for mold fabrication based on said data, and sending said numerical control data to the central processing computer where it is saved;
• and
• (f) a step of getting said numerical control data from the central processing computer and fabricating a mold;
• wherein each of the computer terminal units sends a work completion signal to the central processing computer when it has completed a step assigned to it, and upon receiving the work completion signal, the central processing computer prepares a work item notice that indicates that it is possible to start a next step such that the work item notice can be displayed on a screen of whichever one of the plurality of computer terminal units is assigned to the next step, and the computer terminal unit assigned to the next step allows the displayed work item notice to be clicked to start work on said next step.