High pressure filter with integral relief valve

A spin-on filter for use in high pressure fluid applications comprising:

• a generally cylindrical housing with an open end and a closed end, a rigid cover disposed in said open end of said housing, said cover being of unitary construction including a hub having a first end and a second end, said second end of said hub extending into said housing and having an axial bore defining a exit flow passage extending therethrough, said exit flow passage having an associated diameter, said first end of said hub being connected to a circular rim of said cover by a plurality of radial ribs connected between said hub and said rim defining a entrance flow passage between at least two of said plurality of ribs, said entrance and exit flow passages having associated pressures;
• said open end of said housing surrounding and being folded to interconnect said cover to said housing;
• an annular valve assembly extending from said second end of said hub into said housing having an axial bore extending therethrough, said axial bore having an associated diameter greater than said diameter of said hub, said valve assembly further including a first end proximate said second end of said hub, and a second end, said valve assembly being constructed and arranged to define with said hub an annular valve seat therebetween at said first end of said valve assembly and a relief channel through said Valve seat connecting said entrance flow passage and said exit flow passage;
• a generally cylindrical filter element disposed within said housing, to define an annular chamber around said filter element in fluid communication with said entrance flow passage;
• said filter element having an opened and a closed end, said valve assembly extending into and sealing said open end of said filter element;
• an annular retainer mounted at said second end of said valve assembly;
• an annular baffle plate adjacent said valve seat and said relief channel moveable between a first position closing said relief channel and a second position displaced therefrom;
• a coil spring disposed between said annular retainer and said baffle plate, biasing said baffle plate against said valve seat so that when said pressure in said entrance flow passage exceeds said pressure in said exit flow passage by a predetermined amount said coil spring is compressed to displace said baffle plate from said valve Seat to open said relief channel;
• and
• a bypass filter disposed:, within said valve assembly between said relief channel and said exit flow passage, so that when said baffle plate is in said Second position fluid passes through said relief channel and said bypass filter.

A spin-on filter for high pressure fluid applications comprising:

• a housing having an open end and a closed end, and a tubular filter element disposed therein, said filter element having an open end and a closed end, a cover engaged with said open end of said housing, said cover including a hub extending therefrom, said cover having an entrance flow passage operable in delivering fluid to and external surface of said filter element and said hub having an exit flow passage operable in delivering filtered fluid from Within said filter element, said flow passages having respective pressures;
• a valve assembly extending from said hub into said filter element, to sealingly engage said open end of said filter element, said exit flow passage extending therethrough, said valve assembly being constructed and arranged to define a valve seat having a relief channel therethrough connecting said entrance and exit flow passages;.
• a baffle plate linearly movable between a first position against said valve seat and a second position axially away from said valve seat;
• means for biasing filter said filter plate against said valve seat so that when said pressure in said entrance flow passage exceeds said pressure in Said exit flow passage by a predetermined amount, said baffle plate linearly moves from said first position to said second position and fluid passes through said relief channel;
• and
• a by-pass filter disposed between said relief channel and said exit flow passage, so that fluid passing through said relief channel passes through said by-pass filter.