Oil canning of mesh screen for filter

Abstract

A method of reducing if not eliminating the possibility of tearing or ripping of a mesh screen of a filter during the manufacturing process includes the step of intentionally deforming the mesh screen. With this technique, as the plastic material that forms the frame of the filter begins to expand or change shape, as a result of the heating and squeezing steps involved with the molding process, the deformed mesh screen will be able to stretch or expand without the potential of tearing or ripping of the mesh screen. With the invention, numerous shapes and configurations of tools may be used to provide the intentional deformation of the mesh screen during the manufacturing process as well as to provide for control over the amount and degree of mesh screen deformation. Also, the resulting filter will have a mesh screen that has improved retention capabilities which will enhance the performance of the filter.

1 . A filter comprising: 
 a frame defining frame sections; and    a mesh screen molded within the frame sections, the mesh screen defining a non-planar profile to permit expansion of the mesh screen.    
   
   
       2 . The filter of  claim 1  wherein the frame defines a plurality of frame sections with the mesh screen molded with each of the plurality of frame sections.  
   
   
       3 . The filter of  claim 2  wherein the non-planar mesh screen is dome-shaped.  
   
   
       4 . The filter of  claim 1  wherein the non-planar mesh screen includes squeezed portions.  
   
   
       5 . The filter of  claim 1  wherein the frame defines a track formed around the mesh screen.  
   
   
       6 . The filter of  claim 5  wherein the track includes a rubber material configured within the track.  
   
   
       7 . A method of manufacturing a filter comprising the steps of: 
 molding a frame defining at least one frame section;    molding a mesh screen across the at least one frame section; and    deforming the mesh screen;    whereby the deformed mesh screen permits expansion of the mesh screen.    
   
   
       8 . The method of  claim 7  further comprising the step of molding a seal around the at least one frame section.  
   
   
       9 . The method of  claim 7  wherein the at least one frame section is a plurality of frame sections.  
   
   
       10 . The method of  claim 9  further comprising the step of molding the mesh screen across the plurality of frame sections.  
   
   
       11 . The method of  claim 10  further comprising the step of deforming the mesh screen that extends across the plurality of frame sections.  
   
   
       12 . The method of  claim 7  wherein the deformed mesh screen has a non-planar profile.  
   
   
       13 . The method of  claim 12  wherein the non-planar mesh screen is dome-shaped.  
   
   
       14 . The method of  claim 8  wherein the step of molding a seal around the at least one frame section includes the use of a liquid injection molding process.  
   
   
       15 . A method of manufacturing a filter comprising the steps of: 
 molding a frame defining a plurality of frame sections;    molding a mesh screen across at least one of the plurality of frame sections;    molding a seal around at least one of the plurality of frame sections; and    deforming the mesh screen;    whereby the deformed mesh screen permits expansion of the mesh screen.    
   
   
       16 . The method of  claim 15  further comprising the step of molding the mesh screen across the plurality of frame sections.  
   
   
       17 . The method of  claim 16  further comprising the step of deforming the mesh screen that extends across the plurality of frame sections.  
   
   
       18 . The method of  claim 17  wherein the deformed mesh screen has a non-planar profile.  
   
   
       19 . The method of  claim 18  wherein the non-planar mesh screen is dome-shaped.  
   
   
       20 . The method of  claim 18  wherein the non-planar mesh screen defines at least one squeezed portion and a non-squeezed portion.