Structure of a vertical-type, acid and base resistance pump

#(a) Field of the Invention

#The present invention relates to an improved structure of a vertical-type acid and base resistance pump, and in particular, a pump having a shaft cap mounted with seals contacting with the ceramic ring mounted to the pump.

#(b) Description of the Prior Art

#FIG. 1 is a perspective exploded view of a conventional pump system

#FIG. 2 is a sectional view of a conventional pump system.

#FIG. 3 is a partial enlarged view of the conventional pump system.

#Referring to FIGS. 5, 6 and 7, there are a partial enlarged sectional view, a sectional view and an exploded perspective view of a vertical-type, acid and base resistance pump structure in accordance with the present invention. The pump comprises a motor 10, a seal cap 2, a ceramic ring 21, two seals 33, 34, a shaft cap 3, a propeller wheel 32, and a body 4. The front section of the motor 10 is provided with a long shaft center 1, and in order to protect the shaft center 1 from the entering of corrosive fluid, the shaft cap 3 is tightly sealed to the shaft center 1, and the lower end of the shaft cap 3 and the tubular section of the propeller wheel 32 are mounted as one unit. The exterior of the shaft center 1 is mounted with the body 4. The bottom section of the body 4 is provided with an outlet tube 41.

#In accordance with the present invention, in order to prevent external gas from entering the pump so as to improve the vacuum of the pump, a seal cap 2 is mounted between the motor 10 and the top section of the body 4. The bottom section of the seal cap 2 is provided with a large size, and thick ceramic ring 21. In accordance with the present invention, in order to prevent external gas from entering the pump so as to improve the vacuum of the pump, and to mitigate the drawback of the conventional vertical-type pump which absorbs gas, the shaft cap 3 is mounted with seals 33, 34 at the positive face and the reverse face of the shaft cap 3. The material of the seals 33, 34 is high abrasive resistance material. The two seals 33, 34 are symmetrical in a top and bottom position and are mounted onto the ceramic ring 21.

#In operation, the two faces of the dry-type seals 33, 34 will contact and abrade with the top and bottom face of the ceramic ring 21. The heat produced by such abrasion will be dissipated from the ceramic ring 21 and the seal cap 2 to the external air. As the seals 33, 34 located at the top and bottom of the ceramic ring 21 are of larger size, the ceramic ring 21 is always in contact and in abrasion relation. In other words, whether when the pump is shut-off or is running, the sealing of the ceramic ring 21 is complete and the external air will not enter the pump by means of vacuum suction or the pressure as a result of pump operation. This is because the mounting of the two dry-type seals 33, 34 prevents air from entering the pump. Thus the pump has improved the vacuum condition and the working efficiency is upgraded. Furthermore, other than acid and base are prevented from moving upward, when the pump is not running, the corrosive fluid in the outlet tube 41 will not reach the seals 33, 34 and the ceramic ring 21 to produce overflow. Thus, no leakage or overflow of the corrosive fluid occurred and naturally the seal of the motor 10 will not be damaged, and the environment will not be polluted.