Patent Publication Number: US-11660561-B2

Title: Filter element with endcap having rigid reinforcing member

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application a continuation of U.S. patent application Ser. No. 16/062,482, filed Jun. 14, 2018, which is a U.S. National Stage Application of International Application No. PCT/US2016/066583, filed on Dec. 14, 2016, which claims priority to U.S. Provisional Patent Application No. 62/267,389, filed Dec. 15, 2015. The contents of these applications are incorporated herein by reference in their entirety. 
    
    
     TECHNICAL FIELD 
     The present application relates generally to fluid filtration systems. More particularly, the present application relates to filter elements for filtration systems. 
     BACKGROUND 
     Various types of fluid filtration systems incorporate environmentally friendly filters, commonly known as “green” filters. Generally, these filters include filter elements that can be removed from the filter body for replacement of the filter element, thus eliminating the need to replace the entire filter. In addition, these filter elements are generally made of materials that are incinerable, allowing for easy and safe disposal of the filter cartridge after use. 
     A filter element generally comprises a filter media having one or more endcaps coupled to ends of the filter media. The endcaps are configured so as to hold the filter media and form a seal between the filter element and a permanent standpipe inserted in a central annulus of the filter media such that a clean side and a dirty side of the filter media are separately maintained. In such “green” filters, the endcaps may be formed from a flexible, incinerable material, such as polyurethane. The flexibility of the material allows the endcap to provide a radial compression force on the filter media in order to ensure the seal between the filter element and the standpipe. 
     Due to, for example, exposure to various fluids and high heat environments, the inner diameter of the endcap that forms the seal between the standpipe and the filter element may increase over time, resulting in a decline in the radial compression force on the filter media and a loss of the seal between the filter element and the standpipe. For example, an endcap formed of polyurethane alone may result in a gap of about 1-2 mm between the inner diameter of the endcap and the standpipe after only 72 hours in a high temperature, fluid-soaked environment, whereas a minimum of 250 hours is expected for the working life of typical filter elements. 
     SUMMARY 
     Various embodiments provide for a filter element comprising a filter media having a first end and a first endcap coupled to the first end of the filter media. The first endcap includes a flexible first endcap body having a first endcap rigid reinforcing member internally embedded therein. The first endcap rigid reinforcing member may comprise a wire mesh screen and the filter media may comprise a pleated filter media. The filter element may further comprise a second endcap coupled to a second end of the filter media. The second endcap may include a flexible second endcap body having a second endcap rigid reinforcing member internally embedded therein. 
     Additional embodiments provide for a method of forming a filter element, comprising placing a first endcap rigid reinforcing member in a first endcap mold; adding a liquid polymer to the first endcap mold such that the liquid polymer completely covers the first endcap rigid reinforcing member when the first endcap rigid reinforcing member is placed in the first endcap mold; placing a first end of a filter media into the first endcap mold; and allowing the liquid polymer to harden, thereby coupling a first endcap formed by the liquid polymer and the first endcap rigid reinforcing member to the filter media. 
     Another embodiment relates to a filter housing. The filter housing includes a first section formed of plastic and having a first sealing surface. The plastic forming the first scaling surface is reinforced with a first embedded reinforcement member. The filter housing further includes a second section removably coupled to the first section. The first section and the second section form an internal compartment configured to house a filter component. The second section is formed of plastic and has a second scaling surface. The plastic forming the second scaling surface is reinforced with a second embedded reinforcement member. The filter housing further includes a seal member positioned between the first scaling surface and the second sealing surface. 
     These and other features, together with the organization and manner of operation thereof, will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, wherein like elements have like numerals throughout the several drawings described below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a side view of a filter element, according to an example embodiment. 
         FIG.  2 A  is a top view of an endcap for the filter element of  FIG.  1   . 
         FIG.  2 B  is a top, perspective view of the endcap for the filter element of  FIG.  1   . 
         FIG.  3    is a top, perspective view of an inner portion of the endcap for the filter element of  FIG.  1   . 
         FIG.  4    is a front view of a rigid reinforcing member for the endcap of the filter element of  FIG.  1   , according to an example embodiment. 
         FIGS.  5 A- 5 E  are perspective views showing a process for forming an endcap for a filter element, according to an example embodiment. 
         FIG.  6    is a graph showing an installation force for the filter element having the endcap according to the example embodiment after being subjected to an aging test. 
         FIG.  7    is a graph showing a removal force for the filter element having the endcap according to the example embodiment after being subjected to an aging test. 
         FIG.  8 A  is a perspective view of a filtration system housing according to another example embodiment. 
         FIG.  8 B  is a cross-sectional view of a top of the filtration system housing of  FIG.  8 A . 
     
    
    
     DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS 
     Various example embodiments provide for a filter element that is configured to better maintain a sufficient seal on a permanent standpipe over time. In particular embodiments, an endcap is provided for green filters that includes the flexibility necessary to impart a radial compression force sufficient for sealing, but maintains a rigidity to prevent deformation and ensure that the seal between the filter element and the standpipe is maintained during an expected working life of the filter element. In further arrangements, a filtration system housing includes an embedded component that provides higher rigidity at a sealing surface of the housing. In such arrangements, the embedded component helps to reduce warping that can occur during use at elevated temperatures, which increases reliability of the seal formed against the sealing surface. 
       FIG.  1    shows a filter element  100  according to an example embodiment. The filter element  100  includes a filter media  110 , a first endcap  130 , and a second endcap  150 . The filter media  110  depicted in  FIG.  1    is substantially cylindrically-shaped and includes an inner annulus  115  that extends along a longitudinal axis of the filter element  100 . The inner annulus  115  defines an opening  113  for the passage of a working fluid through the filter media  110 . As shown in  FIG.  1   , the filter media  110  may be a pleated filter media, which includes a plurality of pleats  111  extending along the longitudinal axis of the filter media  110 . However, the filter media  110  is not limited to a pleated configuration and may, alternatively, comprise other types of filter media, such as a filter media with tetrahedron channels formed therein. Such an arrangement is described, for example, in U.S. Pat. No. 8,397,920, the contents of which are incorporated herein by reference. The filter element  100  may be configured for use in filtration systems for fuel and/or lube filtration. However, the filter element  100  may alternatively be configured for use in other types of filtration systems, such as for gas or air filtration. 
     As shown in  FIG.  1   , the first endcap  130  is coupled to a first end of the filter media  110 , and the second endcap  150  is coupled to a second end of the filter media  110  substantially opposite to the first end of the filter media  110 . Each of the first endcap  130  and the second endcap  150  are over-molded to the first and second ends of the filter media  110  in a particular embodiment. Moreover, as will be described in more detail below, the second endcap  150  may be configured in the same or substantially the same manner as the first endcap  130  and, in a particular embodiment, is formed of the same material as the first endcap  130 . However, in other embodiments, the filter element  100  may include only one endcap (e.g., first endcap  130 ) that is over-molded to one end of the filter media  110  according to the example embodiments described below, while the other endcap (e.g., second endcap  150 ) is configured in a different manner, such as an embedded endcap, and may be formed of different materials. 
     As shown in  FIGS.  2 A- 2 B , the first endcap  130  comprises a first endcap body  139  that includes an annular portion  131 , which defines a central flow passage  133 . The central flow passage  133  is in fluid communication with the opening  113  of the filter media  110 . The first endcap body  139  further includes an inner sealing portion  135 , which extends along a portion of an inner circumferential surface of the inner annulus  115  in the longitudinal direction of the filter element  100 . The first endcap body  139  also includes an outer sealing portion  137 , which extends along a portion of an outer circumferential surface of the filter media  110 . The inner sealing portion  135  includes an inner diameter that is sized and configured to seal against a standpipe (not shown) by imparting a radial compression force on the standpipe when the filter element  100  is installed. An upper surface of the first endcap body  139  may be substantially flat or may curve downwardly from a center of the first endcap body  139  in the longitudinal direction of the filter media  110 . 
     The first endcap body  139  of the first endcap  130  comprises a flexible, incinerable material. In a particular embodiment, the first endcap body  139  of the first endcap  130  is formed of polyurethane, but the first endcap body  139  may be formed of any other flexible, incinerable material appropriate for disposal purposes. Accordingly, as shown in the figures, the structure and the material of the first endcap body  139  of the first endcap  130  serves to hold and seal the plurality of pleats  111  of the filter media  110 . In addition, due to the flexibility of the first endcap body  139 , the inner sealing portion  135  of the first endcap body  139  is configured to directly seal with the permanent standpipe such that a dirty side of the filter media  110  and a clean side of the filter media  110  are separately maintained. 
       FIG.  3    shows a top, perspective view of an inner portion of the first endcap  130 . As shown in  FIG.  3   , integrally formed and embedded within the annular portion  131  of the first endcap body  139  is a first endcap rigid reinforcing member  140 . The first endcap rigid reinforcing member  140  comprises a disc-like shape that includes outer and inner diameters. As shown in  FIG.  3   , the inner diameter of the first endcap rigid reinforcing member  140  may be larger or smaller than the inner diameter of the inner sealing portion  135 . In some embodiments, the inner diameter of the first endcap rigid reinforcing member  140  may have an interference. The interference may be, for example, about 1 mm, as compared to the inner diameter of the inner scaling portion  135 . In this case, the first endcap rigid reinforcing member  140  may be located and centered by its inner diameter in relation to the inner diameter of the inner scaling portion  135 . Alternatively, however, the inner diameter of the first endcap rigid reinforcing member  140  may be substantially equal to the inner diameter of the inner sealing portion  135 . In addition, the outer diameter of the first endcap rigid reinforcing member  140  may be substantially equal to or smaller than the outer diameter of the annular portion  131 . If the first endcap rigid reinforcing member  140  is located and centered by its outer diameter in relation to the outer diameter of the annular portion  131 , a gap may be present between in inner diameter of the first endcap rigid reinforcing member  140  and the inner diameter of the inner sealing portion  135 . In particular embodiments, in order to provide sufficient reinforcement to the first endcap  130 , the surface area of the first endcap rigid reinforcing member  140  ranges from about IA to substantially the same surface area of the first endcap  130 . 
     The first endcap rigid reinforcing member  140  comprises a rigid, incinerable material such that the first endcap rigid reinforcing member  140  reinforces the flexible first endcap body  130 . In a particular embodiment, the first endcap rigid reinforcing member  140  is formed of polyamide, but may be formed of any other incinerable material having sufficient rigidity for reinforcing the first endcap body  139 , such as, for example, polypropylene, polyethylene, or polybutylene terephthalate. The first endcap rigid reinforcing member  140  allows for the flexibility of the inner sealing portion  135  to be maintained in order to provide a sufficient radial compression force on the standpipe when the filter element  100  is installed, but imparts enough rigidity within the first endcap body  130  such that deformation of the inner diameter of the inner sealing portion  135  is limited and a sufficient radial compression force is maintained during the working life of the filter element  100 . In a particular embodiment, the second endcap  150  is structured the same or substantially the same as the first endcap  130  shown in the figures. For example, a second endcap rigid reinforcing member may comprise a rigid, incinerable material (such as, for example, polypropylene, polyethylene, or polybutylene terephthalate). 
     As shown in  FIG.  4   , the first endcap rigid reinforcing member  140  may be configured as a wire mesh screen having a plurality of long wires  141  and a plurality of cross wires  143 . The plurality of long wires  141  may extend substantially parallel to one another in a long direction. The plurality of cross wires  143  may extend substantially parallel to one another in a cross direction, which extends substantially perpendicular to the long direction. The plurality of long wires  141  and the plurality of cross wires  143  are formed in a woven lattice pattern where each of the plurality of cross wires  143  alternately overlaps or underlays each of the plurality of long wires  141 . Alternatively, in other embodiments, the first endcap rigid reinforcing member  140  may be configured as a non-woven wire mesh (e.g., as an extruded screen). The plurality of long wires  141  and the plurality of cross wires  143  may have substantially equal diameters. The diameters of the wires may range from about 0.35 mm to about 1.5 mm. In a particular embodiment, the diameters of the wires are about 0.7 mm. In addition, the plurality of long wires  141  and the plurality of cross wires  143  may be spaced from an adjacent wire by substantially equal widths  145 . The widths  145  may range from about 0.5 mm to about 4 mm. In a particular embodiment, each of the widths  145  is about 2 mm. A thickness of the first endcap rigid reinforcing member  140  may range from about 0.35 mm to about 3 mm, but may be about 1.35 mm in particular embodiments. In addition, in some embodiments, the second endcap  150  may also include a second endcap rigid reinforcing member configured as a wire mesh screen having the same or substantially the same dimensions as the wire mesh screen provided as the first endcap rigid reinforcing member  140 . 
       FIGS.  5 A- 5 E  illustrate an over-molding process for forming the filter element  100  having a first endcap  130  and a second endcap  150  with first and second endcaps rigid reinforcing members according to an example embodiment. As shown in  FIGS.  5 A- 5 E , a first endcap rigid reinforcing member  140  is placed in an endcap mold  200 . Liquid polyurethane (or another suitable liquid polymer) for forming the first endcap body  139  is added to the endcap mold  200  to over-mold the first endcap rigid reinforcing member  140  in the formed endcap. As shown in  FIG.  5 C , the over-molding process allows the liquid polyurethane to completely cover the first endcap rigid reinforcing member  140  such that the first endcap rigid reinforcing member  140  is internally embedded within the formed endcap. As shown in  FIG.  5 D , one end of the filter media  110  is then placed in the endcap mold  200  and the liquid polyurethane is allowed to harden, thus coupling the endcap to the one end of the filter media  110  to form the first endcap  130 . The process may be repeated on the other end of the filter media  110  to form the second endcap  150  having a second endcap rigid reinforcing member (with the same mold or different molds being used for each end depending upon the configuration of the filter elements and manufacturing specifications). The steps of the process is not limited to the order described and may be performed in various orders. For example, the liquid polyurethane may be added to the endcap mold  200  before the first endcap rigid reinforcing member  140  is placed in the endcap mold  200  or both the first endcap rigid reinforcing member  140  and the one end of the filter media  110  may be placed in the endcap mold  200  before the liquid polyurethane is added to the endcap mold  200 . 
     As described above, the first endcap rigid reinforcing member  140  provides reinforcement to the endcap in order to maintain rigidity and ensure the seal of the inner sealing portion  135  on the standpipe, even in high temperature, fluid-soaked environments.  FIGS.  6  and  7    are graphs representing comparison results of filter elements having endcaps according to the example embodiments described above. Filter elements A-C were new filter elements that were not subjected to aging, while filter elements D-F were used filter elements that were subjected to aging. In aging filter elements D-F, each of the filter elements was soaked in premium oil at 125° C. for a total of 250 hours.  FIG.  6    shows the force required to install the filter elements on a standpipe, while  FIG.  7    shows the force required to remove the filter elements. As shown in  FIG.  6   , while filter elements A-C generally required a higher force for installation than filter elements D-F, the decrease in the force of installation of filter elements D-F was minimal, suggesting that sufficient radial compression force was maintained even after an expected working life of the filter element in a high temperature, fluid-soaked environment. Similarly, as shown in  FIG.  7   , the filter elements A-F exhibited removal forces that were substantially equal, further indicating that the seal between the filter elements D-F and the standpipe was maintained even after aging. 
     Referring to  FIG.  8 A , a perspective view of a housing  800  of a filtration system is shown according to another example embodiment. Generally, the housing  800  includes a first section  802  and a second section  804  (positioned underneath the first section  102  in  FIG.  8 A ). The first section  802  and the second section  804  may be formed, for example, of a plastic through an injection molding process. The first section  802  and the second section  804  are removably coupled to each other and form an internal compartment  806 . The internal compartment  806  is structured to house various separator and/or filter components (e.g., a filter element, a crankcase ventilation coalescer, etc.). In some arrangements, the housing  100  is a housing for a crankcase ventilation system that separates oil and aerosols from crankcase blowby gases of an internal combustion engine. 
     When the first section  802  and the second section  804  are coupled to each other (e.g., as shown in  FIG.  8 A ), a seal member (not shown) may be positioned between sealing surfaces of the first section  802  and the second section  804  to form a seal between the first section  802  and the second section  804 . The seal between the first and second sections  802  and  804  prevents fluid being filtered through the housing  800  from leaking out of the housing  800  and bypassing the housed filter components. As shown in  FIG.  8 B , the first section  802  includes a sealing surface  808 . The sealing surface  808  is generally planar and is structured to form a seal against the seal member. If the sealing surface  808  warps during use (e.g., due to a combination of high pressures within the internal compartment and elevated temperature operating conditions), the seal formed against the seal member may weak or break, thereby reducing the efficiency of the filtration system. For example, if the sealing surface  808  bends or flexes away from the seal member, the seal formed between the seal member and the sealing surface  808  may be broken. 
     Accordingly, the sealing surface  808  may be reinforced such that the sealing surface remains generally planar during operating conditions. To help increase the rigidity of the sealing surface  808 , the first section  802  includes a reinforcement member  810  embedded within the material forming the first section  802  (e.g., embedded within the plastic material). The material forming the first section  802  may be overmolded onto the reinforcement member  810 . In some arrangements, the reinforcement member  810  is a rigid plate (e.g., formed of metal or a rigid plastic, such as nylon) that is molded in with the first section  802  with a thin coating of plastic to form the sealing surface  808 . The reinforcement member  810  is more rigid than the material used to form the first section  802 . Accordingly, the reinforcement member  810  reduces the risk of bowing, flexing, or warping of the sealing surface  808  thereby reducing the risk that the seal formed between the sealing surface  808  and the seal member breaks. The sealing surfaces of the second section  804  can be reinforced with similar reinforcement members in the same manner as described above with respect to the first section  802  (e.g. with a rigid plastic or metal serving as a rigid plate). 
     Although  FIGS.  8 A and  8 B  detail the reinforcement of a sealing surface  808  of a housing  800 , it should be understood that similar concepts may be applied to non-housing structures, such as filter cartridge endcaps. In such instances, the filter cartridge endcap may be formed of a liquid polymer that is less rigid than an injection molded plastic (i.e., less rigid than the material used to form the housing  800 ), and the reinforcement member may be formed of nylon that is potted into the filter cartridge endcap. 
     The term “coupled” and the like as used herein mean the joining of two members directly or indirectly to one another. Such joining may be stationary (e.g., permanent) or moveable (e.g., removable or releasable). Such joining may be achieved with the two members or the two members and any additional intermediate members being integrally formed as a single unitary body with one another or with the two members or the two members and any additional intermediate members being attached to one another. 
     References herein to the positions of elements (e.g., “upper,” “inner,” “outer,” etc.) are merely used to describe the orientation of various elements in the figures. It should be noted that the orientation of various elements may differ according to other exemplary embodiments, and that such variations are intended to be encompassed by the present disclosure. 
     It is important to note that the construction and arrangement of the various example embodiments are illustrative only. Although only a few embodiments have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, various parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter described herein. For example, elements shown as integrally formed may be constructed of multiple parts or elements, the position of elements may be reversed or otherwise varied, and the nature or number of discrete elements or positions may be altered or varied. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. Other substitutions, modifications, changes and omissions may also be made in the design, operating conditions and arrangement of the various example embodiments without departing from the scope of the concepts presented herein.