Abstract: A filter apparatus includes a fluted filter element in a filter housing having a first open end and a second closed end. The filter element includes fluted filter media coiled into a cylindrical shape and may include an end cap for support and fluid control. Fluid flows into the open end and either around the filter to the closed and back through the filter element or through the filter element to the closed end and then back through a central opening in the filter element.

Abstract: The present invention relates to a filter including a filter element having a sucession of inner connected pleats. The pleats have successive pleat tips which define an outer boundary of the filter element. Covering the entire outer boundary of the filter element is a permeable generally inelastic sheet which extends across successive pleat tips. The sheet is adhesively affixed to the pleat tips for maintaining spacing of the pleats. The sheet comprises of plurality of randomly arranged plastic filaments which are bonded to each other junctions between the filaments and define a plurality of randomly spaced and shaped opening for allowing substantially unrestricted flow of a fluid through the sheet.

Abstract: A spin-on fluid filter cartridge with a replaceable filter element is provided, comprising a housing, an internally threaded annular collar, a replaceable filter element, and an externally threaded mounting head assembly. The annular collar is secured inside the housing at its open upper end. A sealing ring in an annular channel adjacent the external threads of the mounting head seals the cartridge when the mounting head assembly is threaded into the annular collar.