Patent ID: 7022228
Filing Date: 2006-04-04
Classification: B01D

Abstract:
1. A filter device, comprising: a cup-shaped filter housing defining a longitudinal axis; a filter element insertable into and removable from said filter housing along said longitudinal axis; and retaining means detachably securing said filter element in said filter housing and including first and second retaining elements which interact with one another, one of said first and second retaining elements being on one of an inner surface said filter housing and an outer surface said filter element, the other of said first and second retaining elements being on the other of said inner surface of said filter housing and said outer surface of said filter element, each of said first retaining elements being a guide groove concentric to said longitudinal axis having a first portion opening and extending substantially parallel to said longitudinal axis and a second portion extending from said first portion, having a thread pitch relative to said longitudinal axis and defining a cam path, each of said second portions being defined between substantially parallel and opposed wall surfaces extending helically about said longitudinal axis, each of said second retaining elements being a cam extending transversely to said longitudinal axis and received in the respective guide groove when said filter element is received in said filter housing; whereby said filter element is moved axially into said filter housing as said cams enter said first portions, and is rotated about said longitudinal axis causing said cams to enter said second portions as said filter element moves axially and rotationally simultaneously to form an interlocking connection between said filter element and said filter housing.