Patent ID: 7591643

Claim:
A mold for forming a product from a melted material, comprising, first and second mold parts movable with respect to each other to contact each other in such a manner that a cavity is formed therebetween so that the melted material is capable of being inserted into the cavity and being subsequently solidified in the cavity to form the product, and to be separated from each other in such a manner that the product is capable of being taken out of the cavity, wherein one of the first and second mold parts has a material path for injecting the melted material into the cavity in such a manner that the melted material oriented along an injecting axis flows into the cavity, the other one of the first and second mold parts has a surface capable of defining a part of the cavity when the melted material is injected into the cavity, and an ejector pin including a front end surface capable of defining another part of the cavity when the melted material is injected into the cavity, wherein the ejector pin is movable with respect to the surface of the other one of the first and second mold parts between a retracted position and a projected position so that at least a part of the product is released from the other one of the first and second mold parts, wherein the ejector pin has a fluid path for enabling a gaseous fluid to pass through the ejector pin so that the front end surface is capable of being cooled by the gaseous fluid and a longitudinal outer peripheral surface extending in a longitudinal direction of the ejector pin, and the fluid path opens to an outer environment of the ejector pin at only a part of the longitudinal outer peripheral surface to allow the gaseous fluid to be discharged from an inside of the ejector pin to the outer environment of the ejector pin at only the part of the longitudinal outer peripheral surface when the ejector pin is positioned at its retracted position, and the part of the longitudinally outer peripheral surface is closely covered by the other one of the first and second mold parts to restrain the gaseous fluid from being discharged from the inside of the ejector in to the outer environment of the ejector pin when the ejector pin is positioned at its projected position to push out the product from the other one of the first and second parts.