| 摘要 |
PURPOSE:To prevent fault of pump by communicating the suction port through an air collection tank with a liquid storage tank when the discharge port of vaccum pump is communicating with the atmosphere through operation of four- way valve thereby preventing mixture of solid material or liquid with suction air. CONSTITUTION:A suction tube 7 from the suction port 5 of vacuum pump 4 and a discharge tube 8 from the discharge port 6 are coupled with a suction/discharge tube 10 while a four-way valve 9 is placed at the joint and an air collection tank 12 communicating with the suction port 5 of vacuum pump 4 is placed in the way of said tube 1. When said port 6 is communicating with the liquid storage tank, the suction port 5 will communicate through an air collection tank 12 with the atmosphere while when the discharge port 6 is communicating with the atmosphere, the suction port 5 will communicate through the air collection tank 12 with the liquid storage tank 1. Consequently mixture of solid material or liquid is prevented to prevent fault of vacuum pump 4. |
