| 摘要 |
PURPOSE:To permit automatic gas and/or liquid ventilation by drilling communication holes on the upper and lower sides of the both walls partitioning a pump chamber and a rotor chamber and installing, in said communication holes, a check valve which obstructs the counter-flow of the treated liquid supplied from the pump chamber. CONSTITUTION:When the treated liquid in a pump chamber 18 and in the motor part 12, is discharged, the piping system of the pump is cut-off, and the vent 72 formed in the pump part 10 is opened, then all the treated liquid in the pump chamber 18 can be discharged outside. During this period, if the liquid level in the pump chamber 18 lowers below the at in the motor part 12, and the liquid pressure in the motor part 12 rises above that in the pump chamer 18, the check valve part 12 rises above that in the pump chamber 18, the check valve 70 fitted in the communication holes 68 on the lower sides of both walls 50 is opened. Then, the treated liquid in the motor part 12 is automatically discharged into the pump chamber 18 through the communication hole 68 under the action of the check valve 70. |
