One Element Within Another Patents (Class 210/342)
  • Patent number: 3986958
    Abstract: A fluid filter for swimming pools and the like is disclosed. The filter includes a cylindrical housing internally of which are concentrically and nestingly positioned an inner, primary filter that is generally cup-shaped and an outer generally cup-shaped secondary filter, each of which have transversely extending base walls. The housing of the filter includes fluid inlet and outlet means as well as a valve for opening and closing a drain passageway that provides fluid communication between the interior of the filter and discharge conduit means. The valve includes a flapper that is hingedly secured to the transverse base wall of the primary filter with means being included for raising and lowering the flapper from a remote position such as the top of the cylindrical housing after the cover therefor has been removed. The flapper valve permits the rapid discharge of the filter contents through the discharge conduit to a waste line.
    Type: Grant
    Filed: June 6, 1975
    Date of Patent: October 19, 1976
    Inventor: Peter Alesandrio Cattano