Liquid Filtering Device

Abstract

A filter arrangement for liquids has a filter housing and a functional carrier arranged inside the filter housing. A cylindrical filter element is inserted axially into the filter housing and defines an unfiltered side and a filtered side inside the filter housing. A non-return diaphragm is secured within the filter housing, wherein the non-return diaphragm is arranged on the functional carrier so as to effect an axial and/or radial sealing action of the unfiltered side relative to the filtered side of the filter arrangement.

1 .- 11 . (canceled) 
     
     
         12 . A filter arrangement for liquids, the filter arrangement comprising:
 a filter housing;   a functional carrier arranged inside the filter housing;   a cylindrical filter element inserted axially into the filter housing and defining an unfiltered side and a filtered side inside the filter housing;   a non-return diaphragm secured within the filter housing, wherein the non-return diaphragm is arranged on the functional carrier so as to effect an axial and/or radial sealing action of the unfiltered side relative to the filtered side of the filter arrangement.   
     
     
         13 . The filter arrangement according to  claim 12 , wherein the non-return diaphragm is comprised of an elastomer and is attached to an axial projection of the functional carrier in such a way that the non-return diaphragm has a contact on sealing surfaces of the filter housing which contact is flexible within predetermined limits in an axial direction of the filter arrangement. 
     
     
         14 . The filter arrangement according to  claim 13 , wherein the axial projection of the functional carrier is sized such that the axial projection, upon contacting a step of the filter housing, provides a stop so that a length of the axial projection defines a predetermined pretension of the non-return diaphragm when resting against the sealing surfaces. 
     
     
         15 . The filter arrangement according to  claim 12 , wherein the functional carrier is a central tube that is metal-free and fixedly connected to the filter element, wherein the non-return diaphragm is fixedly attached to the central tube. 
     
     
         16 . The filter arrangement according to  claim 12 , wherein the functional carrier is a metal-free central tube that is fixedly mounted on the filter housing, wherein the non-return diaphragm is fixedly mounted on the central tube. 
     
     
         17 . The filter arrangement according to  claim 12 , wherein the functional carrier is an end plate connected fixedly to the filter element, wherein the non-return diaphragm is attached to the end plate. 
     
     
         18 . The filter arrangement according to  claim 12 , wherein the functional carrier is an end plate fixedly connected to the filter element, wherein the non-return diaphragm is attached to the end plate, wherein the end plate has radial noses that laterally engage matching recesses of the filter housing, wherein the recesses are sized such that, when the recesses are contacted by the radial noses, a stop is formed that defines a remaining space, wherein the remaining space provides a predetermined pretension when the non-return diaphragm contacts the sealing surface of the filter housing. 
     
     
         19 . The filter arrangement according to  claim 12 , wherein the functional carrier is an end plate connected with a snap-on connection to the filter element, wherein the non-return diaphragm is attached to the end plate, wherein radial snap-on noses of the end plate engage laterally intermediate spaces of folded filter webs of the filter element above an axial glued connection of the filter webs and, when doing so, extensions of the non-return diaphragm are radially and/or axially clamped between the functional carrier and the filter element for sealing purposes. 
     
     
         20 . The filter arrangement according to  claim 12 , wherein the non-return diaphragm is fixedly connected to the functional carrier by gluing, welding, or by a two-component method. 
     
     
         21 . The filter arrangement according to  claim 12 , wherein the non-return diaphragm is detachably connected to the functional carrier by coupling. 
     
     
         22 . The filter arrangement according to  claim 12 , wherein a liquid to be filtered is fuel or a lubricant for an internal combustion engine of a motor vehicle.