Fluid filter assembly with concave surface in the closed end of the housing

Abstract

A filter assembly includes a house open at one end and closed at the other end. An end plate is secured to the housing and closes the open end. An annular filter media/core assembly is disposed in the housing. The end plate has inlet openings and an outlet opening therein. A combination valve disposed between the end plate and the annular filter media/core assembly controls fluid flow through the inlet openings and the outlet opening. The closed end has a concave portion which is disposed in the opening in the annular filter media/core assembly. The concave portion in the housing helps reduce the overall height of the filter assembly, thus reducing the interior void volume of the filter assembly, which reduces the quantity of oil necessary to fill the system. The provision of a concave portion in the closed end of the housing helps to center the annular filter media/core assembly in the housing and improves the manufacturing and assembly processes.

1 . A filter assembly having a housing open at one end and closed at the other end, a concave portion being formed in the closed end of the housing, an annular filter media/core assembly disposed in said housing, with the concave portion being disposed in the opening in the annular filter media/core assembly, an end plate secured to the housing and closing the open end thereof, the end plate having first inlet opening means, second inlet opening means and outlet opening means, a combination valve disposed between the annular filter media/core assembly and the end plate for controlling fluid flow through the first inlet opening means and the second inlet opening means, the combination valve including a first portion cooperating with the first inlet opening means and a second portion cooperating with the second inlet opening means, the second portion having more resistance to fluid flow than the first portion, whereby, in normal operation, the first portion will yield prior to the second portion and fluid flow will pass through the first inlet opening means, the annular filter media/core assembly and then be discharged through said outlet opening means and when the annular filter media/core assembly begins to clog, pressure upstream of the first portion will build and upon attainment of a predetermined pressure, the second portion will open the second inlet opening means and fluid flow can pass through the second inlet opening means and out the outlet opening means bypassing the annular filter media/core assembly.  
   
   
       2 . A filter assembly as in  claim 1  including resilient means disposed between the top of the annular filter media/core assembly and the concave surface of the housing for sealing fluid flow between the top of the annular filter media/core assembly and the concave portion of the housing and for biasing the annular filter media/core assembly toward the end plate.  
   
   
       3 . A filter assembly as in  claim 1  wherein the combination valve comprises an annular member, with the first portion extending outwardly from a central portion and the second portion extending inwardly from the central portion, the second portion being stiffer than the first portion; the annular filter media/core assembly engaging the central portion of the combination valve between the first portion and the second portion to retain the combination valve in place.  
   
   
       4 . A filter assembly as in  claim 3  wherein the annular filter media/core assembly includes a central core surrounded by filter media, and a resilient seal on the lower end of the central core engages the central portion of the combination valve for sealing between the lower end of the central core and the combination valve.  
   
   
       5 . A filter assembly as in  claim 1  wherein the end plate has an inclined surface inclined with respect to the longitudinal axis of the housing and a transverse surface transverse to the longitudinal axis of the housing, the first inlet opening means being disposed in the inclined surface and the second inlet opening means being disposed in the transverse surface.  
   
   
       6 . A filter assembly as in  claim 1  wherein the first inlet opening means comprises a plurality of openings.  
   
   
       7 . A filter assembly as in  claim 1  wherein the second inlet opening means comprises a plurality of openings.  
   
   
       8 . A filter assembly as in  claim 1 , wherein the annular filter media/core assembly comprises a core, a filter media surrounding the core and end caps at the ends of the filter media, the filter media and end caps being fabricated from materials that can be bonded to fuse the components to one another and preclude any significant fluid flow there between.  
   
   
       9 . A filter assembly as in  claim 8 , wherein the filter media and the end caps are ultrasonically welded to one another.  
   
   
       10 . A filter assembly as in  claim 5  wherein the second portion has a surface engaging the end plate and a surface engaging the central core.  
   
   
       11 . A filter assembly having a housing opening at one end and closed at the other end, said closed end having a concave portion formed therein, an annular filter media/core assembly disposed in said housing and having a central opening in the upper end thereof, the concave portion of the housing being disposed in the central opening to help center the annular fitter media/core assembly in the housing, an end plate secured to the housing and closing the end plate having first inlet openings, second inlet openings and an outlet opening the open end thereof, and a combination valve disposed between the annular filter media/core assembly and the end plate for controlling fluid flow through the first and second inlet openings, the combination valve including a first portion cooperating with the first inlet openings and a second portion cooperating with the second inlet openings, the second portion having more resistance to fluid flow than the first portion, whereby in operation, the first portion will yield in response to minimum pressure and fluid flow will pass through the first inlet openings, the annular filter media/core assembly and then be discharged through the outlet opening and when the annular filter media/core assembly begins to clog, pressure will begin to build and upon attainment of a higher predetermined pressure, the second portion will open the second inlet openings and fluid flow can pass through the second inlet openings and out the outlet opening, bypassing the annular filter media/core assembly.  
   
   
       12 . A filter assembly as in  claim 11  wherein the combination valve comprises an annular member, with the first portion extending outwardly from a central portion and the second portion extending inwardly from the central portion, the second portion being stiffer than the first portion; the annular filter element engaging the central portion of the combination valve between the first portion and the second portion to retain the combination valve in place.  
   
   
       13 . A filter assembly as in  claim 12  including resilient seal means disposed between the top of the annular filter media/core assembly and the inside surface of the concave portion of the housing for sealing between the annular filter media/core assembly and the inside surface of the concave portion of the housing and for biasing the annular filter media/core assembly toward the end plate to help retain the combination valve in place.  
   
   
       14 . A filter assembly as in  claim 13  including resilient seal means disposed between the bottom of the annular filter media/core assembly and the combination valve for sealing between the bottom of the annular filter media/core assembly and for helping to retain the combination valve in place.  
   
   
       15 . A filter assembly as in  claim 11 , wherein the closed end of the housing lies in a plane, with the concave portion extending inwardly from said plane.  
   
   
       16 . A filter assembly having a housing open at one end and closed at the other end, said other end having a concave portion formed therein, an annular filter media/core assembly disposed in said housing and having a central opening in the upper end thereof, the concave portion of the housing being disposed in the central opening to help center the annular fitter media/core assembly in the housing, an end plate secured to the housing and closing the open end, and a combination valve for controlling fluid flow through the filter assembly.  
   
   
       17 . A filter assembly as in  claim 16 , including resilient seal means disposed between the top of the annular filter media/core assembly and the inside surface of the concave portion of the housing for sealing between the annular filter media/core assembly and the inside surface of the concave portion of the housing and for biasing the annular filter media/core assembly toward the end plate to help retain the combination valve in place.  
   
   
       18 . A filter assembly as in  claim 16 , wherein the closed end of the housing lies in a plane, with the concave portion extending inwardly from said plane.