Liquid pressure accumulator systems

Claim 1

A pressure liquid accumulator tank comprising a hollow cylindrical housing, a generally cylindrically shaped diaphragm extending the length of said housing secured within and dividing said housing into an air chamber and a liquid chamber, the liquid chamber being interior of said diaphragm, two ports in said housing one communicating with each chamber for admission of air under pressure to said air chamber and liquid under pressure to said liquid chamber respectively, a keeper plate securing said diaphragm to one end of said housing and includes the liquid port, said liquid chamber being bounded solely by said diaphragm and said keeper plate, means for maintaining the amount of air in said air chamber substantially constant when in use, said means comprising an arrangement whereby as the quantity of liquid in said liquid chamber varies said diaphragm will move between two positions within said housing representing a minimum liquid pressure and a maximum liquid pressure, said diaphragm being integrally formed solely of flexible rubber material and having two substantially concentric portions extending substantially parallel to the sidewalls of said housing, one end of the outer concentric portion being secured to the housing by said keeper plate in sealing relation, one end of the inner concentric portion being connected to the other end of said outer concentric portion, the inner concentric portion being joined to a membrane portion which extends substantially across the housing to close the other end of said inner concentric portion, said keeper plate also including an annular shoulder and a rigid circular immovable plate extending parallel to and spaced from the surface of said annular shoulder and keeper plate thereby defining said liquid port, said annular shoulder having a diameter larger than that of said circular plate, said fixed plate receiving in abutting relation a portion of said diaphragm membrane portion, said shoulder having an inclined face adjacent said circular plate, said shoulder and the edge of said circular plate forming a seating surface against which a portion of the diaphragm membrane portion also abuts to effectively seal said liquid port when liquid pressure falls to a minimum.