Automatic Back wash filter strainer

(1)The liquid enters from N2 at the bottom of the cylinder into the filter, passing through the fixed cartridge, the liquid exit from N1 at the center of the filter from outside toward inside. Backwash pollutants discharged from N3.

2)Liquid flow from the cartridge medial (pollution side) to the lateral(clean side), solid particles are trapped in the filter inside, with the increase of pollutants, the differential pressure between the pollution side and the clean side gradually increases. When the pressure reachs the pre-determined value (the value can be empirical value or debugging value ) , the filter automatically start the backwash process.

Filtration process:* The speed reducer drives the washing arm by the middle connecting shaft. The washing arm rotational angle is controled by the infrared correlation orientation to align with the filter cartridge.

* The sewage valve is open and creates pressure difference between the lateral(clean side) and the outlet.

* Under the pressure difference, the clean lateral liquid flow from outside to inside and begin the backwashing. Filter pollutants cumulate at the inner part are cleaned and discharged from N3 outlet.

* The backwashing time of the cartridge can be adjusted automatically according to process variations. When the time is up, the sewage valve will close down and the cartridge backwash will end. The gear motor rotates the washing arm to start the backwash of the next cartridge, opening the sewage valve again, this process is repeated until all the cartridges are backwashed.

* The whole backwash term has N-1 groups (N is the number of cartridges). As a term is over, the washing arm stays on the position of N-1and waits for the next term backwash.

* Since the filter backwash process is done in a group,during the backwash process, the filter is in a continuous state of filtration.