Fluid filter having a reusable filter housing and a replaceable coreless filter element

A reusable fluid filter assembly, comprising:

• a cylindrical housing having an annular peripheral wall, an open end, a closed end, connecting means for removably connecting said open end of said housing to a top plate assembly, and hollow central core having a tubular shape, an inner surface, an open first end having a first outer surface, a middle portion having a middle outer surface and a plurality of fluid outlet perforations extending from said inner surface to said middle outer surface, and a second end having a second outer surface, said first end being disposed in said open end of said housing, means for fixedly connecting said second end to said closed end of said housing;
• a top plate assembly having a rim, fluid inlet means and fluid outlet means extending through said top plate assembly, and connecting means for removably connecting said top plate assembly to said open end of said housing;
• a top plate attachment member positioned between the first end of said core and said top plate assembly, said top plate attachment member having a tubular shape, an outer surface, a pilot end having internal threads for threading onto corresponding external threads on a filter mounting base, and a fluid outlet port extending through said attachment member;
• a replaceable coreless filter element disposed in said housing to define a fluid inlet chamber between said filter element and said housing, said filter element being without any supporting internal core, said filter element having a hollow cylindrical fluid outlet chamber which opens to a first open end of said filter element, allowing filtered fluid to flow therefrom, and having a second open end, said filter element having an outer diameter that is smaller than an inner diameter of said housing to allow removal of said filter element through the open end of said housing, and said filter element having an inner diameter that is larger than the outer diameter of said hollow central core to allow said hollow cylindrical chamber to accept said hollow central core therein;
• said fluid inlet means of said top plate being in fluid communication with said fluid inlet chamber defined by said filter element and housing;
• said hollow central core extending into said first open end and said hollow cylindrical chamber of said filter element, said fluid outlet perforations of said hollow central core being in fluid communication with said hollow cylindrical chamber of said filter element;
• said first and second outer surfaces of said hollow central core sealingly engaging said first and second open ends of said filter element respectively;
• and
• said open first end of said hollow central core sealingly engaging said fluid outlet port extending through said attachment member.