Pneumatically-operated filtering apparatus with filter movement controlled by level sensor

摘要

Filtering apparatus employs both pneumatic controls and a pneumatic drive to eliminate all electrical components. The filtering apparatus includes a perforate plate and a tank with a strip of filtering media supported on the plate. Contaminated liquid is supplied from above and clean liquid is removed from below the filtering media and plate. The filtering media is advanced across the plate by conveying apparatus. The pneumatic drive for the conveying apparatus is operated by pneumatic controls and a float which actuates the drive when the liquid in the tank rises to a predetermined level as the filtering media becomes plugged. The drive is shut off when the liquid drops to a lower predetermined level.