Abstract:
A filter element for a paint sprayer having a feed line includes a core defining a first end, a second end, and a central portion extending along an axis between the first end and the second end. The central portion includes a central aperture closed at the first end and open at the second end and a plurality of openings that extend through the core to the central aperture. A mesh member surrounds the central portion and an adapter is coupled to the second end. The adapter includes a flowpath therethrough, an outer cylindrical surface, and an annular surface. The annular surface is operable to engage an end of the feed line such that the adapter is operable to form an axial seal between the adapter and the feed line.

Description:
RELATED APPLICATION DATA 
       [0001]    This application claims priority to U.S. Provisional Application No. 61/611,761 filed Mar. 16, 2012, the entire contents of which are incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    Embodiments of the invention relate to filters for use with paint sprayers. More particularly, the invention relates to a universal filter for use with multiple paint sprayers. 
         [0003]    Tools such as paint sprayers utilize spray guns to evenly apply paint to a surface. Paint sprayers utilize paint filters to ensure that debris or foreign objects are not sprayed or pulled into the paint sprayer. The filters prevent obstructions from clogging an outlet of the spray gun that could result in unevenness of the application. 
       SUMMARY 
       [0004]    Spray guns used in conjunction with paint sprayers have variable sized conduits that receive the paint filters. Accordingly, embodiments of the present invention provide a filter assembly. The filter assembly includes a filter having a threaded core encased in a mesh overlay. The core includes a main channel or aperture that receives paint through auxiliary openings or apertures. The filter has a first end that is closed and a second end that is open. The first end of the filter is coupled to a cap, while the second end of the filter is coupled to an adaptor. The adaptor maintains the opening in the main channel of the filter. The adaptor further includes a resilient flange that generates a fluidic seal with different sized conduits thereby allowing the filter assembly to be used with different types of paint sprayers. 
         [0005]    In one construction, the invention provides a filter element for a paint sprayer having a feed line. The filter element includes a core defining a first end, a second end, and a central portion extending along an axis between the first end and the second end. The central portion includes a central aperture closed at the first end and open at the second end and a plurality of openings that extend through the core to the central aperture. A mesh member surrounds the central portion and an adapter is coupled to the second end. The adapter includes a flowpath therethrough, an outer cylindrical surface, and an annular surface. The annular surface is operable to engage an end of the feed line such that the adapter is operable to form an axial seal between the adapter and the feed line. 
         [0006]    In another construction, the invention provides a filter element for use with a plurality of different-sized feed lines. The filter element includes a cylindrical filter including a closed end, an open end, and a central portion between the closed end and the opened end. An adapter is coupled to the second end. The adapter includes an outer cylindrical surface having an outside diameter and an annular surface that extends from the outside diameter to an outside flange diameter. The outer cylindrical surface and the feed line cooperate to form a radial seal when the feed line has an inside diameter that is substantially the same as the outside diameter. The annular surface and the feed line cooperate to form an axial seal when the inside diameter is larger than an inside diameter that is capable of forming a seal with the cylindrical surface. 
         [0007]    In still another construction, the invention provides a filter element for use with a first paint sprayer having a first feed line and a second paint sprayer having a second feed line, the first feed line having a first inside diameter that is different than a second inside diameter of the second feed line. The filter element includes a core defining a first end, a second end, and a central portion extending along an axis between the first end and the second end. The central portion includes a central aperture closed at the first end and open at the second end and a plurality of openings that extend through the core to the central aperture. An adapter is coupled to the second end and includes a flowpath therethrough. The adapter includes an outer cylindrical surface having an outside diameter and an annular surface that extends from the outside diameter to an outside flange diameter. The first inside diameter is such that the first feed line and the outer cylindrical surface cooperate to define a radial seal, the second inside diameter being larger than the first inside diameter and not sealingly engageable with the outer cylindrical surface. An end of the second feed line sealingly engages the annular surface to form an axial seal between the second feed line and the adapter. 
         [0008]    Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a perspective view of a filter assembly embodying the invention. 
           [0010]      FIG. 2  is an exploded view of the filter assembly in  FIG. 1 . 
           [0011]      FIG. 3  is a side view of a core included in the filter assembly in  FIG. 1 . 
           [0012]      FIG. 4  is a cross-sectional view of the core of the filter assembly in  FIG. 3  along  4 - 4 . 
           [0013]      FIG. 5  is a side view of an overlay included in the filter assembly in  FIG. 1 . 
           [0014]      FIG. 6  is a cross-sectional view of a cap included in the filter assembly in  FIG. 1 . 
           [0015]      FIG. 7  is a cross-sectional view of an adaptor included in the filter assembly in  FIG. 1  with a first feed line attached. 
           [0016]      FIG. 8  is a cross-sectional view of an adaptor included in the filter assembly in  FIG. 1  with a second feed line attached. 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. 
         [0018]      FIGS. 1 and 2  illustrate a filter assembly  10  that includes a cap  12 , an adaptor  14 , and a filter  16 , therebetween. The filter assembly  10  is generally cylindrically shaped and includes a first end  18  and a second end  20 . The filter assembly  10  includes a core  22  encased or contained within a mesh cover or overlay  24 . The overlay  24  closely surrounds the core  22  from the first end  18  of the filter  16  to the second end  20  of the filter  16 . The core  22  and overlay  24  are coupled to the cap  12  at the first end  18  of the filter assembly  10  and attached to the adaptor  14  at the second end  20  of the filter assembly  10 . 
         [0019]    Referring to  FIGS. 3 and 4 , the core  22  includes a housing  26  that is preferably formed of a plastic material, and extends substantially from the first end  18  of the filter assembly  10  to the second end  20  of the filter assembly  10 . The core  22  also includes a first side  28  and a second side  30 . The core  22  defines a main aperture or channel  32 . The channel  32  extends from the first end  18  of the filter assembly  10  to the second end  20  of the filter assembly  10  along axis A. The channel  32  includes a closed end or portion  34  at the first end  18  of the filter assembly  10  and an opening  36  at the second end  20  of the filter assembly  10 . The core  22  includes a plurality of auxiliary apertures or openings  38  that access the main channel  36 . The apertures  38  are oriented substantially perpendicular to the main channel  36 . In the illustrated embodiment, the apertures  38  are staggered between the first and second sides  28 ,  30  of the core  22 . In other embodiments, the apertures could be directly across from one another. Additionally, other embodiments could include more or less auxiliary apertures or apertures of different shapes, sizes, or orientations so long as the apertures are able to direct fluid to the channel  32 . 
         [0020]    Further with respect to  FIGS. 3 and 4 , the core  22  includes a threaded portion  40 , a first unthreaded portion  42  at the first end  18 , and a second unthreaded portion  44  at the second end  20 . In the illustrated embodiment, the first unthreaded portion  42  makes up a larger portion of the housing  26  than the second unthreaded portion  44 . It is contemplated that in future embodiments, the unthreaded portions relative to each other and relative to the threaded portion could be different or could have different dimensions and orientations. The closed end  34  of the channel  32  is within the first unthreaded portion  42 , while the second unthreaded portion  44  surrounds the opening  36  in the main channel  32 . 
         [0021]    Referring to  FIG. 5 , the mesh overlay  24  (which encases the core  22 ) extends substantially the length of the core  22  along axis A. The mesh overlay  24  is preferably formed from plastic with metals or other materials also being suitable. The mesh overlay  24  wraps around the housing  26  so that a portion  46  of the overlay overlaps itself. The lattice of the mesh overlay  24  includes a portion  48  having large openings and portions  50 ,  52  having small openings. The large opening portion  48  is disposed between the first end  18  and the second end  20 . As such, the large opening portion  48  substantially covers the threaded portion  40  of the core  22 . A first small opening portion  50  covers the first end  18  of the core  22  and a second small opening portion  52  covers the second end  20  of the core  22 . The portion  46  of the mesh overlay  24  includes small openings that are the result of the overlapping layers of the mesh material. The portion  46  having small openings, extends between the first and second ends  18 ,  20  of the filter assembly  10  along axis A. The dimensions, shapes and orientation of openings in the mesh overlay demonstrated in  FIG. 5  are one possible embodiment of the lattice of the overlay, and in other embodiments, the openings may have any suitable dimensions, shapes and orientation. 
         [0022]    With respect to  FIG. 6 , the cap  12  includes a housing  54  formed from a plastic material, or other suitable material, and having a first portion  56  and a second portion  58 . The cap  12  is substantially cylindrical. The first portion  56  of the cap  12  includes a first diameter  60  and a second diameter  62  having a step  64  therebetween. A substantially circular opening  66  having a uniform diameter  68  is included in the first portion  56  of the cap  12 . The second portion  58  of the cap  12  includes a diameter  70  that is larger than both first and second diameters  60 ,  62  of the first portion  56  of the cap  12 . The second portion  58  of the cap  12  includes a substantially circular opening  72  having a uniform diameter  74 . The opening  72  is sized to couple to the first end  18  of the filter assembly  10 . Therefore, the opening  72  in the second portion  58  of the cap  12  receives the first unthreaded portion  42  of the core  22  which is surrounded by the mesh overlay  24 , described above. The cap  12  also includes a wall or partition  76  that separates the first portion  56  of the cap  12  from the second portion  58  of the cap  12 . The core  22  and mesh overlay  24  can be press fit into the cap  12  or the cap can be bonded or otherwise attached. In still other constitutions, the cap  12  is molded into position. 
         [0023]    With reference to  FIG. 7 , the adaptor  14  includes a housing  78  formed from a plastic material, or other suitable material, and includes a first portion  80  and a second portion  82 . The adaptor  14  is substantially cylindrical. The first portion  80  has a diameter  84  and defines a first opening  86 . The first opening  86  is substantially cylindrical with a uniform diameter  88 , and is sized to receive the second end  20  of the filter assembly  10  thereby surrounding the second unthreaded portion  44  of the core  22  enclosed within the mesh overlay  24 . The second portion  82  of the adaptor  14  has a second or outside diameter  90 , which may be smaller than the first diameter  88 , and defines a second opening  92 . The second opening  92  is substantially cylindrical with a uniform diameter  94  that is smaller than the diameter  88  of the first opening  86 . The core  22  and mesh overlay  24  can be press fit into the adaptor  14  or the adaptor can be bonded or otherwise attached. In still other constructions, the adaptor  14  is molded into position. 
         [0024]    Further with respect to  FIG. 7 , the adaptor  14  includes a recess  96  and a resilient flange  98  between the first and second portions  80 ,  82  of the housing  78 . The recess  96  is between the first portion  80  of the housing  78  and the flange  98 . The recess  96  includes a diameter  100  smaller than the diameter  84  of the first portion  80  and larger than the outside diameter  90  of the second portion  82  of the adaptor  14 . The flange  98  is positioned between the recess  96  and the second portion  82 . An outside flange diameter  102  of the flange  98  defines the largest diameter of the filter assembly  10 . The flange  98  defines an annular planar surface  103  that is oriented substantially normal to the axis A when the adaptor  14  is attached to the remainder of the filter assembly  10 . 
         [0025]    In operation, the filter assembly  10  is installed into a tool having a conduit (not shown) that houses the filter assembly  10 . Because tool conduits have a variety of sizes, the resilient flange  98  enables the filter assembly  10  to be compatible with a plurality of tools. The flange  98  allows the adaptor  14  to generate a fluidic seal with conduits of different sizes. 
         [0026]      FIG. 7  also demonstrates that the openings  86 ,  92  extend through the adaptor  14  and extend the main channel  32 . The first and second openings  86 ,  92  are in fluid communication with the main channel  32  of the core  22  thereby preserving the channel  32 . When assembled, the second end  20  of the core abuts an internal step  104  such that the outlet of the channel  32  is positioned adjacent one end of the second opening  92 . In the preferred constructions, the diameter  92  is similar to the diameter of the channel  32 . 
         [0027]    To assemble the filter assembly, the core is first formed using any suitable process or processes. The mesh overlay is then positioned around the core. In one construction, the cap and the adaptor are then molded onto the core and mesh overlay to complete the assembly. In other constructions, the mesh overlay is first connected to itself to form a tube having the core disposed therein. The cap and the adapter are then attached to the mesh overlay and the core using a suitable attachment method (e.g., thermal bonding, adhesives, welding, brazing, etc.) to complete the assembly. 
         [0028]    In operation, the filter assembly is disposed within a paint supply such that paint surrounds the exterior of the assembly. The adaptor is coupled to a feed line  105  that extends to a paint gun, a pump, a sprayer or another device. The suction side of the pump is in fluid communication with the filter assembly, via the feed line such that during pump operation, a vacuum or low pressure region is produced within the channel  32 . The low pressure draws paint through the apertures in the mesh overlay and through the openings  38  in the core. As the paint passes through the mesh overlay, particles larger than the mesh opening are blocked from entry. 
         [0029]    In preferred constructions, the diameter  90  is sized to fit closely within the feed line  105 , or component on the end of the feed line  105 , to form a seal. Thus, in arrangements in which an inside diameter  120  of the feed line is about the same diameter as the outside diameter  90 , the feed line  105  and the adapter cooperate to form a radial seal therebetween. The size difference between the adapter and the feed line can vary depending on many factors including suction pressure and the resilience of the various components. However, in most applications, the inside diameter should be no more than twenty percent smaller than the outer diameter  90  in which case the feed line  105  will expand to receive the adapter and no more than twenty percent larger than the outside diameter. Sizes within this range can be considered about the same for purposes of forming a radial seal. 
         [0030]    In arrangements in which the feed line  105  is too large to form a seal (e.g., about 20 percent larger than the outside diameter  90 ). The adapter is still capable of forming a seal. As illustrated in  FIG. 8 , the feed line  105  includes a substantially annular end  125  that contacts the annular surface  103  to form an axial seal therebetween. As suction is applied, the adapter is pulled into further engagement with the end  125  of the feed line to improve the seal. 
         [0031]    In some constructions, the outside diameter  90  and the inside diameter  120  of the feed line  105  are such that both a radial seal and an axial seal can be formed further enhancing the operation of the filter assembly  10 . 
         [0032]    It should be noted that while the filter assembly  10  has been described as being used with a paint gun or to filter paint, the filter assembly  10  could be used with other components and could filter other fluids such as stain, sealers, and the like.