Patent ID: 7393455

Claim:
An apparatus for filtering a highly pressurized fluid, wherein the fluid is pressurized by a pump upstream of said apparatus, comprising: a vertical housing having a transparent outer cover, a fluid inlet for communicating a highly pressurized fluid into said housing, and a fluid outlet for communicating said highly pressurized fluid downstream of said housing; a filter element disposed within said housing between said fluid inlet and said fluid outlet for filtering said fluid; a cover disposed on said filter element to define a fluid impervious region of said filter element adjacent to a top end of said filter element and a fluid permeable region of said filter element adjacent to a bottom end of said filter element; a relief valve mounted in a top of said filter element, and said relief valve opening at a predetermined pressure; said outer cover of said housing having a bottom portion with a substantially continuous first inner diameter defined throughout said bottom portion wherein said bottom portion of said outer cover extends at least from said bottom end of said filter element to said fluid impervious region of said filter element to define a lower predetermined volume between said bottom portion of said outer cover and said filter element; and said outer cover of said housing having an upper portion with a substantially continuous second inner diameter defined throughout said upper portion, wherein said upper portion extends from said top end of said filter element to said bottom portion to define an upper predetermined volume between said upper portion of said outer cover and said filter element, and said second inner diameter being smaller than said first inner diameter, wherein the level of fluid within said housing provides a visual indicator as to the overall condition of the filter element.