| 摘要 |
PURPOSE:To prevent the occurrence of wall lacking such as blowholes and pinholes by providing a spray pipe of the type having a nozzle for spraying a powdered material to the mold surface in one end, and opening in the powdered material within a reservoir in other end, and providing a device for supplying a venturi air into the spray pipe. CONSTITUTION:A nozzle 6a for spraying a powdered material to the mold surface is provided in one end of a spray pipe 6, and a opened part 6b in other end is positioned within the powdered material in a reservoir. A dried air is injected into the spray pipe 6 from an air container 13 through a venturi air supplying device 7, wherein, the powdered material 3 within the reservoir 2 is sucked from the opened end 6b of the spray pipe 6 into the spray pipe through a venturi effect of the injected air, and then sprayed from the spray nozzle 6a to the undercut part A of the mold. It is sufficiently applied with the powdered material up to the corner thereof, and thus, a uniform skin layer is secured throughout the whole of the undercut part. |
