| 摘要 |
A top-flow fluid pump that is made from a high-purity fluroplastic material is disclosed. The pump is used to circulate extremely corrosive fluids that are heated to temperatures of 160-180° C. through at least one filtration unit. The pump can be used in a semiconductor etching system. The pump utilizes the driven side of an impeller to generate a suction force that draws the corrosive fluid into a pumping chamber from at least one inlet port. A pedestal support or shaft sleeve, through which a motor drive shaft extends, is modified to create an annular passageway that permits the corrosive fluid to enter the pumping chamber from the inlet. With the inlet design of the present invention, a drive motor seal assembly is no longer subjected to corrosive fluid because the seal assembly is positioned on the suction side of the impeller. In a "dead headed" condition, the corrosive fluid flow stops completely as the fluid within the pumping chamber simply remains in shear. |
