| 摘要 |
PURPOSE:To prevent the molten resin from entering into a porous part and to facilitate the injection molding of the synthetic resin, by using a porous alloy member to make a part of a pasage for supplying pressurized gas into a cavity and by cooling the porous alloy member when the pressurized gas is supplied. CONSTITUTION:A valve 6 is opened to supply pressurized gas from a pressurized gas source 7 into a metal mold cavity 1 through a passage hole 5, a porous sintered alloy member 4 and a pressurized gas distribution channel 8 to keep the cavity 1 under the pressurized gas. At that time, the sintered alloy member 4 is cooled by the pressurized gas which flows through the member. When resin made plastic by heat but not yet foamed is injected, the pressurized gas is removed out of the cavity and returned into the pressurized gas source 7 through said passages in reverse. Since the pressurized gas acts to the metal mold cavity 1, the resin is kept from being foamed. After the resin injection, the valve 6 is closed and a pressurized gas releasing valve 12 is opened to entirely remove the pressurized gas to foam and mold the injected resin. |
