Patent ID: 6210577
Filing Date: 2001-04-03
Classification: B01D

Abstract:
A housing assembly (10) for the filtration of a liquid, for temporarily holding at least a lower replaceable filter cartridge (14) and an upper replaceable filter cartridge (16), each with a closed top and an open end nose (15,17), the housing assembly comprising:a) a cap-shaped bottom housing (20) with a flat bottom surface (37) having a lip (21) surrounding a first recess (26), with first fastening means (22) and first sealing means (25, 24, 28, 27, 32, 31), surrounding a second recess (33), smaller than the first recess, and having an outlet (34, 36);b) an tube-shaped extension housing (50) having a cavity (51), for receiving at least a lower cartridge (14) and an upper cartridge (16), having at its lower opening second fastening means (51, 52, 53, 54, 56) and second sealing means (55, 59, 161, 162) engaging the first fastening and the first sealing means of the bottom housing, respectively, for providing a fastening and sealing first interface to the bottom housing, the extension housing having at its upper opening a lip (91), surrounding a third recess (96) with third fastening means (92) and third sealing means (95, 94, 98, 97, 103, 101), and having an inlet (60);c) a cap-shaped top housing (120) having fourth fastening means (122, 126) and fourth sealing means (125, 129, 165, 166) engaging the third fastening and sealing means of the extension housing, respectively, for providing a fastening and sealing second interface to the extension housing to form a closed sealed cavity of the housing assembly (10);d) first receiving means (40) for concentrically and sealingly receiving the nose (15) of the lower cartridge (14) within the housing assembly (10), and having fifth sealing means (41, 42, 43, 44) against the pressure drop across the lower cartridge (14);e) second receiving means (170) for concentrically and sealingly receiving the nose (17) of the upper cartridge (16) within the housing assembly (10), and having sixth sealing means (171, 172, 173, 174) against the pressure drop across the upper cartridge (16), the receiving means being adapted for redirecting the liquid flow from the nose of the upper cartridge to the outside surface of the lower cartridge;f) first centering means (82) for concentrically receiving the top end of the lower cartridge (14) within the housing assembly (10);g) second centering means (114) for concentrically receiving the top end of the upper cartridge (16) within the housing assembly (10); whereinthe liquid to be filtered enters the inlet (60) in the extension housing (50), flows radially through the cylindrical portion of upper cartridge (16) and via its nose (17) through the second receiving means (170) and the first centering means (82) where it is redirected to flow radially through the cylindrical portion of the lower cartridge (14) and via its nose (15) through the means (40) for concentrically and sealingly receiving the nose (15) of the lower cartridge (14), to the outlet (34, 36) of the bottom housing (20).