| 摘要 |
PURPOSE:To prevent abrasion and damage of a vacuum pump by casting sand, etc. by communicating a suction pipe to the suction port of the vacuum pump by way of a dust tube type filter device. CONSTITUTION:When a suction pipe 20 is commuicated to the molding flask or disintegrating position and a vacuum pump device 14 is driven, the air mixed with fine casting sand passes through a feed port 8 and is sucked into a lower chamber 7, where it circulates round the circumferential surfaces of dust tubes 9, 9 and is led into an upper chamber 6. On the way of this, the casting sand in the air is fallen by a baffle plate 5 and is perfectly prevented from flowing into the upper chamber 6 through dust tube 9. The air which does not contain casting sand at all and which has been admitted into the upper chamber 6 passes through a check valve 11, conduit 12 and gate valve 13 through exhaust port 10 and is drawn into the vacuum pump device 14 through suction port 15, following to which it passes through a conduit 17 and silenser 18 through exhaust port 16 and is released into the atmosphere. |
