Patent ID: 7967981

Claim:
A filter assembly ( 10 ) for filtering fluids, comprising: an elongated container ( 3 ), open at one end and provided at the bottom of the closed end with first centering means ( 11 ) for a filter cartridge and further provided with engagement means ( 31 ) formed on its inner surface; a cylindrical filter cartridge ( 4 ) housed inside said container ( 3 ), with the inner diameter of said container near the open end being larger than the diameter of said filter cartridge ( 4 ); a cover ( 1 ) adapted to close by screwing the open end of said container ( 3 ) and provided with second centering means ( 12 ) for positioning said filter cartridge ( 4 ); an additional centering member ( 9 ) which is at least partially radially elastic and secured to the outer surface of said filter cartridge ( 4 ) and cooperating with said engagement means ( 31 ) for keeping said cartridge centered when screwing said cover ( 1 ) to said container ( 3 ); wherein said container ( 3 ) is frusto-conical and said additional centering member ( 9 ) comprises a strip of plastic material, at least partially flexible, provided with at least a portion ( 20 , 21 ) adapted for engaging said engagement means ( 31 ) located on the inner surface of said container ( 3 ); said centering member ( 9 ) having at least one engagement portion ( 21 ) comprising a rigid projection ( 20 ), and said engagement means ( 31 ) on the inner surface of the container formed as seats having a complementary shape to said rigid projection(s); said assembly ( 10 ) providing for a nut ring ( 2 ) on the external surface of said container ( 3 ) for the screwing engagement with said cover ( 1 ); said container ( 3 ) manufactured from a plastic material ; said assembly ( 10 ) further comprising a seal ( 13 ) between the container ( 3 ) and the cover ( 1 ), said seal ( 13 ) comprising a member of a deformable synthetic material, said seal ( 13 ) overmoulded on the upper edge of said container ( 3 ), said seal ( 13 ) having a profile with at least two separate contact surfaces ( 18 , 19 ) with the cover ( 1 ), said seal ( 13 ) forming a labyrinth configuration.