Internal Magnetic Filter for Hydraulic Systems

Abstract

A simple inlet filter element for use primarily in power steering columns which is comprised of a mesh filter, a magnet attached to the mesh filter and a button cap. The filter is installed in a port or conduit through which steering fluid flows and is held in place by the button cap element.

1 . An internal magnetic filter assembly for use in a power steering pump reservoir comprising:
 a mesh filter bag having an open end portion and a closed terminating end portion;   a button cap having a cylindrical base including:
 one or more bypass holes; and 
 a chamfered cylinder, said chamfered cylinder being configured to connect to an intake to a return port of a reservoir of a power steering fluid system through said cylindrical base; and 
   a magnet located within and attached to said mesh filter between said open end portion and said closed terminating end portion;   wherein said open end portion of said mesh filter bag is attached to said cylindrical base of said button cap; and   wherein a pressure buildup internal to said mesh filter bag from power steering fluid flowing through said filter assembly will cause said power steering fluid to pass through said one or more bypass holes before said mesh filter bag rips, before said mesh filter bag separates from said cylindrical base, and before said chamfered cylinder is dislodged from said intake.   
     
     
         2 . The internal magnetic filter assembly of  claim 1 , wherein said mesh filter bag comprises woven mesh. 
     
     
         3 . The internal magnetic filter assembly of  claim 1 , wherein said mesh filter bag is shaped as a rectangular bag. 
     
     
         4 . The internal magnetic filter assembly of  claim 3 , wherein said closed terminating end portion of said mesh filter bag is closed by a single line of connection forming a fish tail closure. 
     
     
         5 . The internal magnetic filter assembly of  claim 1 , wherein said mesh filter bag is ultra-sonically welded to said button cap. 
     
     
         6 . The internal magnetic filter assembly of  claim 1 , wherein said button cap is comprised of molded plastic. 
     
     
         7 . The internal magnetic filter assembly of  claim 1 , wherein said magnet is in the shape of a ring. 
     
     
         8 . The internal magnetic filter assembly of  claim 1 , wherein said magnet is mechanically attached to said mesh filter bag. 
     
     
         9 . The internal magnetic filter assembly of  claim 8 , wherein said magnet is attached via a method selected from the group consisting of: adhering, sewing, clipping, and combinations thereof. 
     
     
         10 . An internal filter assembly for use in a power steering pump reservoir comprising:
 filter means;   a button cap having a cylindrical base including:
 one or more bypass holes; and 
 means for connecting said button cap to an intake to a return port of a reservoir of a power steering fluid system with sufficient force not to be dislodged by pressure within said power steering fluid system; and 
   a magnet located within and attached to said filter means.