Low-resistance air filter

Abstract

The invention relates to a low resistance air filter. An air cleaner system includes a housing having a first housing end, a second housing end, and an inlet proximate the second housing end, the first housing end having an opening. The air cleaner system also includes a filter element removably mounted within the housing through the opening, the filter element includes a filter media, a first end plate coupled to the filter media at a first filter end, an open second end plate coupled to the filter media at a second filter end, and an annular protrusion extending axially from the open second end plate, the annular projection seals against the housing and creates an axial gap between the filter element and the housing.

Description

[0001] This application is a divisional application of an application filed on November 10, 2020, with application number 202080075668.6, and invention name “Low-resistance air filter”.

[0002] Cross-references to related patent applications

[0003] This application claims the benefit of and priority to U.S. Provisional Application Serial No. 62 / 936,774, filed on November 18, 2019, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0004] The present invention generally relates to filter assemblies for filtering fluids in internal combustion engine systems. background

[0006] Air filters are commonly used to filter air in the intake system of a device such as an internal combustion engine. The air filter includes a housing extending along an axis and having at least one sidewall extending between a first axial end and a second axial end, wherein the sidewall includes an air inlet for receiving dirty incoming air. One axial end of the housing includes an outlet for discharging clean filtered air. The air filter element can typically be axially inserted into the housing through the open axial end. Pressure loss across the air filter is an important performance characteristic, and the lower the pressure loss, the better because the amount of wasted energy is reduced.

[0007] Overview

[0008] According to one embodiment, an air filter system is provided. The air filter system includes a housing having a first housing end, a second housing end, and an inlet proximate the second housing end, the first housing end having an opening. The air filter system also includes a filter element that is removably mounted in the housing through the opening, the filter element including: a filter medium; a first end plate coupled to the filter medium at a first filter end; an open second end plate coupled to the filter medium at a second filter end; and an annular protrusion extending axially from the open second end plate. The annular protrusion seals against the housing and creates an axial gap between the filter element and the housing. Fluid that enters the housing through the inlet flows into the axial gap.

[0009] According to another embodiment, there is provided an air filter system comprising:

[0010] a housing including a first housing end, a second housing end, and an inlet proximate to the second housing end, the first housing end having an opening; and

[0011] a filter element removably mounted in the housing through the opening, the filter element comprising:

[0012] Filter media,

[0013] a first end plate coupled to the filter media at a first filter end;

[0014] an open second end plate coupled to the filter media at a second filter end; and

[0015] an annular projection extending axially from the open second end plate in a direction away from the first end plate, the annular projection sealing against the housing and forming an axial gap between a radially outermost portion of the filter element and the housing proximate the inlet;

[0016] The fluid entering the housing through the inlet flows into the axial gap.

[0017] In some embodiments, the inlet is tangential to the radially outermost portion of the filter element.

[0018] In some embodiments, the first end plate includes a handle assembly including a handle member and a latch that engages an aperture formed in the housing to retain the filter element within the housing.

[0019] In some embodiments, the annular protrusion comprises an annular protrusion outer diameter and the filter medium comprises a filter medium outer diameter, the annular protrusion outer diameter being less than 90% of the filter medium outer diameter.

[0020] In some embodiments, the annular protrusion comprises an annular protrusion length of at least 10 mm.

[0021] In some embodiments, the first end plate extends out of the opening of the first housing end.

[0022] In some embodiments, the housing further comprises a cover removably coupled to the housing proximate the first housing end, the cover defining the opening configured to receive the filter element, the filter element extending through the cover when the cover is coupled to the first housing end and the filter element is positioned within the housing.

[0023] In some embodiments, the first end plate includes a handle assembly, the handle assembly including a handle member, a latch, and a tab extending away from the latch; and the cover includes a cover flange, the cover flange extending axially away from the cover in a direction away from the second shell end, the cover flange including a hole, the hole being configured to receive the tab to retain the filter element within the shell.

[0024] In some embodiments, the filter element is engageable with the cover to form a substantially fluid-tight sealing engagement.

[0025] According to another embodiment, an axially loaded filter element is provided. The axially loaded filter element includes: a filter medium; a closed first end plate coupled to the filter medium at a first filter end and having a handle assembly; an open second end plate coupled to the filter medium at a second filter end; and an annular protrusion extending axially from the open second end plate. The annular protrusion has an annular protrusion diameter that is less than 90% of the outer diameter of the filter medium.

[0026] In some embodiments, the handle assembly includes a handle member and a latch that engages an aperture formed in a housing to retain the axially loaded filter element within the housing.

[0027] In some embodiments, the annular protrusion comprises an annular protrusion length of at least 10 mm.

[0028] In some embodiments, the axially loaded filter element further includes a sealing member positioned around the filter media proximate the closed first end plate, the sealing member configured to engage a cover of the housing to form a substantially fluid-tight seal.

[0029] In some embodiments, the axially loaded filter element further comprises a permeable barrier wrapped around the filter media, the permeable barrier having an average pore size between 20 microns and 200 microns, inclusive.

[0030] According to another embodiment, an air filter system is provided. The air filter system includes a housing and a filter element removably mounted in the housing. The housing includes a first housing end, a second housing end, an inlet and a cover, the inlet being close to the second housing end. The cover is removably connected to the main body of the housing near the first housing end. The cover includes an outer cover surface and an inner cover surface radially separated by the thickness of the cover. The inner cover surface defines a cover opening. The filter element is inserted into the housing via the cover opening. The filter element includes a filter medium, a first end plate connected to the filter medium at a first filter end, and an open second end plate connected to the filter medium at a second filter end. An annular protrusion extends axially from the open second end plate in a direction away from the first end plate. The annular protrusion can be formed of a compliant material, and the compliant material is configured to form a substantially liquid-tight seal with the housing near the second housing end.

[0031] According to another embodiment, there is provided an air filter system comprising:

[0032] a housing including a first housing end, a second housing end, an inlet proximate the second housing end, and a cover proximate a body of the housing to which the first housing end is removably coupled, the cover including an outer cover surface and an inner cover surface radially separated by a cover thickness, the inner cover surface defining a cover opening; and

[0033] a filter element removably mounted in the housing through the cover opening, the filter element comprising:

[0034] Filter media,

[0035] a first end plate coupled to the filter media at a first filter end;

[0036] an open second end plate coupled to the filter media at a second filter end; and

[0037] An annular protrusion extends axially from the open second end plate in a direction away from the first end plate.

[0038] In some embodiments, the first end plate includes a handle assembly removably coupled to the cover.

[0039] In some embodiments, the handle assembly includes a handle member and a latch, the latch including a protrusion; and the cover includes a cover flange, the cover flange extending axially away from the cover in a direction away from the second shell end, the cover flange including a hole, the hole being configured to receive the protrusion and removably connect the filter element within the shell.

[0040] In some embodiments, the shell further includes a shell protrusion extending axially away from the second shell end in a direction toward the first shell end, the shell protrusion facilitating separation between the open second end plate and the second inner end surface of the shell to form an axial gap having a gap width, wherein fluid entering the shell through the inlet flows into the axial gap.

[0041] In some embodiments, the housing further comprises an outlet, the outlet cooperating with the housing protrusion to form a housing cavity for receiving the annular protrusion, the annular protrusion cooperating with the housing cavity to form a substantially fluid-tight seal.

[0042] In some embodiments, the filter element further includes a sealing member positioned around the filter media proximate the first end plate, the sealing member being configured to engage the cover to form a substantially fluid-tight seal.

[0043] These and other features, as well as their organization and manner of operation, will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, in which like elements have like numerals throughout the several figures described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 A front perspective view of an air filter system is shown according to an exemplary embodiment.

[0046] Figure 2 Shows Figure 1 Rear perspective view of the air filter system.

[0047] Figure 3 Shows Figure 1 Top view of the air filter system.

[0048] Figure 4 Shows Figure 1 Front view of the air filter system.

[0049] Figure 5 Shows Figure 1 Side cutaway view of the air filter system.

[0050] Figure 6 According to an exemplary embodiment, Figure 1 A front perspective view of a filter element used with an air cleaner system.

[0051] Figure 7 Shows Figure 6 Rear perspective view of the filter element.

[0052] Figure 8 Shows Figure 6 Side view of a filter element.

[0053] Fig. 9 Shows Figure 6 Front view of the filter element.

[0054] Fig.10 Shows Figure 6 Side cross-sectional view of a filter element.

[0055] Fig.11 A dimensionless pressure loss graph plotted against gap width versus inlet diameter is shown. Detailed Description

[0057] An air filter system is generally described with reference to the accompanying drawings. The air filter system includes a cylindrical air filter element for use in a tangential inlet air filter housing. The air filter housing includes a first axial end and a second axial end, wherein the first axial end includes an opening for receiving the filter element. The filter element can be positioned within the air filter housing and can be accessed through the open first axial end of the air filter system. An end plate of the filter element includes a handle and a latch, which are configured to engage the air filter housing when the filter element is in an installed position. By grasping the handle, a user can release the latch from the air filter housing using a single hand and easily remove the filter element in an axial direction, such as for maintenance or replacement purposes. The filter element is cylindrical, and the air filter housing includes a tangential inlet. The filter element includes an open end cap and a closed end cap. A portion of the open end cap side of the filter element is offset from the second axial end of the air filter housing. The offset creates an axial gap between the air filter housing and the filter element, thereby providing additional flow area, resulting in a lower pressure drop than a conventional filter.

[0058] refer to Figure 1-Figure 5, an air filter system 100 according to an exemplary embodiment is shown. The air filter system 100 includes a housing 102 extending axially along a longitudinal axis 115 and having an annular sidewall 105 extending between a first end 101 and a second end 103. The annular sidewall 105 includes an air inlet 106 configured to guide air into the housing 102 substantially along an inlet direction 112 and an air outlet 108 configured to discharge clean filtered air from the housing 102 substantially along an outlet direction 114. The inlet direction 112 is substantially tangential to an outer surface of a filter element 110 located within the housing 102. Both the air inlet 106 and the air outlet 108 are located near the second end 103 of the housing 102. The housing 102 includes a cover 104 coupled to the first end 101. In some embodiments, the cover 104 is removably coupled to the remainder of the housing 102. For example, the cover 104 can be coupled to the rest of the housing 102 with a latch, fastener, thread, adhesive, bayonet latch, clip or similar coupling. The cover 104 is open at the first end 101 to enable replacement and repair of the filter element 110 without removing the cover 104 from the rest of the housing 102. In other embodiments, the cover 104 is a closed cover so that the cover 104 must be removed to enable replacement and repair of the filter element 110. In some embodiments, the cover 104 is permanently coupled to the rest of the housing 102 so that the cover 104 cannot be removed from the rest of the housing 102 without damaging at least one of the cover 104 and / or another part of the housing 102. In some embodiments, the cover 104 is integrally formed with the body of the housing 102 so that the cover 104 and the body of the housing 102 are formed as a single unit together. In some embodiments, the cover 104 and the body of the housing 102 are formed of different materials. For example, the body of the housing 102 can be formed of metal, and the cover 104 can be formed of plastic.

[0059] The cover 104 defines a substantially annular body having a donut-shaped cross-sectional shape when cut perpendicular to the longitudinal axis 115. When the cover 104 is coupled to the remainder of the housing 102, the cover 104 is centered about the longitudinal axis 115. In some embodiments, when the cover 104 is coupled to the remainder of the housing 102, the cover 104 is concentric with the longitudinal axis 115. The cover 104 defines a substantially annular outer cover surface 120 and a substantially annular inner cover surface 121 ( Figure 5). The outer cover surface 120 and the inner cover surface 121 can be separated by a radial distance, shown as the cover thickness 119. The cover thickness 119 facilitates the positioning of the filter element 110 away from the housing inner surface 129. Positioning the filter element 110 away from the housing inner surface 129 allows fluid to flow between the housing 102 and the filter element 110. In some embodiments, the radial distance between the filter element 110 and the housing 102 (e.g., between the outer surface 127 of the filter element 110 and the housing inner surface 129) is greater than the cover thickness 119.

[0060] The inner cover surface 121 defines a cover opening 141 configured to receive the filter element 110. In some embodiments, the inner cover surface 121 interfaces with the filter element 110. In some embodiments, the inner cover surface 121 is positioned away from the filter element 110 so that a fluid (e.g., air) can flow between the filter element 110 and the inner cover surface 121. Extending in a radial direction from the inner cover surface 121 to the outer cover surface 120 may be a cover flange 142 ( Figure 5 ). The cover flange 142 interfaces with a portion of the filter element 110 to facilitate positioning the filter element 110 within the housing 102. In some embodiments, the filter element 110 cooperates with the cover flange 142 to form a sealing engagement so that fluid cannot flow out of the cover opening 141. In some embodiments, the filter element 110 cooperates with the inner cover surface 121 to form a sealing engagement to prevent fluid from flowing out of the cover opening 141.

[0061] Extending radially away from the outer cover surface 120 may be a cover protrusion 143 configured to be received within a latch member 145 that extends axially away from the body of the housing 102 in a direction away from the air outlet 108. The latch member 145 includes a latch opening 147 that extends through the latch member 145 and is configured to receive the cover protrusion 143. The cover protrusion 143 cooperates with the latch member 145 to removably couple the cover 104 to the remainder of the housing 102.

[0062] The housing 102 also includes a dust extractor port 140. In some embodiments, the dust extractor port 140 extends away from the cover 104. The dust extractor port 140 is in fluid communication with a fluid passage between the outer cover surface 120 and the inner cover surface 121. In some embodiments, the dust extractor port 140 includes a valve. In some embodiments, the dust extractor port 140 is fluidly coupled to a suction conduit that facilitates removal of debris (e.g., dirt, dust, etc.) from within the housing 102.

[0063] Reference Figure 5-Figure 10, the air filter system 100 includes a filter element 110. The filter element 110 is disposed in the housing 102 and extends axially between a first element axial end 111 adjacent to the first end 101 of the housing 102 and a second element axial end 113 adjacent to the second end 103 of the housing 102. In some embodiments, a portion of the first end plate 122 engages with the cover 104 to form a sealing engagement. The first end plate 122 is closed and the second end plate 124 is open. The filter element 110 includes a filter medium 125 arranged in a cylindrical manner, whose inner surface 138 defines a clean air outlet passage 148. The filter medium 125 extends between the first end plate 122 and the second end plate 124. An annular dirty air inlet passage 131 is defined between an outer surface 127 of the filter medium 125 and an inner surface 129 of the housing. The dirty air inlet passage 131 extends into the cover 104 (eg, between the outer cover surface 120 and the inner cover surface 121 ), and the dirty air inlet passage 131 is in fluid communication with the dust extractor port 140 .

[0064] In operation, dirty air enters the air filter system 100 through the air inlet 106 in the inlet direction 112, enters the annular dirty air inlet passage 131, and passes through the filter media 125 in the outside-to-inside direction into the air filter system 100. Clean air flows from the clean air outlet passage 148 and flows through the air outlet 108 in the outlet direction 114.

[0065] Reference Figure 6-Figure 8 , the first end plate 122 includes a handle assembly 130, which is configured to be able to insert and remove the filter element 110 into and out of the housing 102 through the cover opening 141. The filter element 110 can be axially inserted into the housing 102 through the first end 101 (e.g., in an opening formed in the cover 104, in the cover opening 141). A user can access and service the filter element 110 through the cover opening 141. The handle assembly 130 is formed as a single piece with the first end plate 122. The handle assembly 130 includes a handle member 118 and a latch member 116. The latch member 116 includes a tab 126 that interacts with a hole 128 of the housing 102 to lock the filter element 110 in place within the housing 102. The tab 126 extends away from the latch member 116 in a direction away from the longitudinal axis 115. The hole 128 extends through the second cover flange 150, which extends axially away from the housing 102. In some embodiments, the second cover flange 150 extends away from the cover 104 in a direction away from the first end 101 of the housing 102. The second cover flange 150 engages with the latch member 116 to retain the filter element 110 within the housing 102.

[0066] Latch member 116 also includes grip member 136. Latch member 116 is flexible in nature so that a user can press grip member 136 downward to release tab 126 from aperture 128 and use handle member 118 to pull filter element 110 out of housing 102 in an axial direction (e.g., along longitudinal axis 115).

[0067] Reference Figure 3 and Figure 5 , the filter element 110 includes a circular annular annular protrusion 132 extending axially (e.g., along the longitudinal axis 115) from the second end plate end face 123 of the second end plate 124 at the second element axial end 113 of the filter element 110. The annular protrusion 132 extends from the second end plate end face 123 and terminates at the annular protrusion end face 133. The annular protrusion 132 includes a radial outer surface 135 and a radial inner surface 137, both of which extend between the second end plate end face 123 to the annular protrusion end face 133. The annular protrusion 132 is located proximate to the second end 103 of the housing 102, such that the annular protrusion 132 is also located proximate to the air inlet 106 and the air outlet 108 of the housing 102. When the filter element 110 is in the installed position in the housing 102, the annular protrusion 132 is located radially outside the air outlet 108 of the housing 102 (e.g., relative to the longitudinal axis 115 of the housing 102). The annular protrusion 132 is also located radially inside the air inlet 106 of the housing 102. The annular protrusion 132 is centered about the longitudinal axis 115 and is located between the second end plate 124 and the housing inner surface 129. When the filter element 110 is in the installed position in the housing 102, the annular protrusion 132 seals against the housing inner surface 129 at the second end 103 of the housing 102. The annular protrusion end face 133 abuts against the housing inner surface 129 of the housing 102 and seals against the housing inner surface 129 of the housing 102. The radially outer surface 135 of the annular protrusion 132 abuts against the housing inner surface 129 and seals against the housing inner surface 129.

[0068] Reference Figure 7 and Fig. 9, the annular protrusion 132 includes chords 134 inscribed in the annular protrusion 132 (e.g., on the inner radial sealing surface of the filter element 110). In some embodiments, the diameter of the annular protrusion 132 is about 90% of the diameter of the second end plate 124 (e.g., about 90% of the outer diameter of the filter medium / about 90% of the diameter of the outer surface 127 of the filter medium 125). In some embodiments, the diameter of the annular protrusion 132 is 90% or less of the diameter of the second end plate 124 (e.g., 90% or less of the outer diameter of the filter medium / 90% or less of the diameter of the outer surface 127 of the filter medium 125). In some embodiments, the annular protrusion 132 has a length (e.g., axial length) of at least 10 mm. In some embodiments, the length (e.g., axial length) of the annular protrusion 132 is at least 25 mm or about 5% of the total length of the filter element 110.

[0069] The annular housing protrusion 154 extends away from the second end 103 of the housing 102 in a direction toward the first end 101. The housing protrusion 154 extends away from the second inner end surface 156 of the housing 102. The housing protrusion 154 is positioned about the longitudinal axis 115 and defines a diameter that is greater than the diameter of the annular protrusion 132. The housing protrusion 154 and the air outlet 108 cooperate to define an annular housing cavity 158 that is configured to receive the annular protrusion 132. The housing protrusion 154 can be interfaced with the second end plate 124 to position the second end plate 124 away from the housing inner surface 129 (more specifically, away from the second inner end surface 156).

[0070] The annular protrusion 132 forms an axial gap 146 between the radially outermost portion of the filter element 110 and the housing 102. The axial gap 146 is formed between the second end plate 124 and the second inner end surface 156. The gap width 159 is defined as the distance between the second end plate 124 and the second inner end surface 156. The axial gap 146 is located in the incoming airflow (shown by the inlet direction 112) near the air inlet 106 of the housing 102. Therefore, the incoming airflow entering the housing 102 through the air inlet 106 enters the axial gap 146 between the second end of the filter element 110 (e.g., the second end plate 124) and the housing inner surface 129 (e.g., the second inner end surface 156) of the housing 102. The axial gap 146 creates additional flow area for the incoming airflow. By creating additional flow area, the pressure drop is reduced.

[0071] One or more sealing members are used to seal the filter element 110 against the housing 102 (e.g., in the air outlet 108) (e.g., radial seal, axial seal). In various embodiments, different types of seals can be formed in the air filter system 100 described herein. Various types of seals can include axial, radial, elliptical, etc. In some embodiments, the annular protrusion 132 includes a sealing member. In some embodiments, the annular protrusion 132 is formed by a compliant material, which is configured to be compressed in the housing cavity 158 and form a sealing engagement with at least one of the housing protrusion 154 and the air outlet 108. The air filter system 100 may include an auxiliary filter element 160. The auxiliary filter element 160 may include a sealing member 152, which is configured to form an axial seal with the air outlet 108. In some embodiments, the filter element 110 includes a permeable baffle 144 (e.g., a mesh covering) positioned on the outer surface 127 of the filter medium 125. A permeable barrier 144 surrounds the filter media 125 near the air inlet 106 of the air filter system 100. In some embodiments, the average pore size of the permeable barrier 144 is between about 20 microns and 200 microns. In some embodiments, the filter element 110 includes an integrated center tube, and in some embodiments, the first end plate 122 is separate from the center tube.

[0072] Reference Fig.11 , shows a graph 200 of the dimensionless pressure loss 202 plotted against the gap width 159 of the inlet diameter 204. As illustrated by the plotted line 206, as the gap width 159 increases relative to the inlet diameter 204, the dimensionless pressure loss 202 decreases. Thus, by creating the axial gap 146 as described herein, the pressure loss of the air filter system 100 has been reduced. For example, Figure 3 As shown, the gap width 159 is approximately 33% of the diameter of the inlet 106. Referring to graph 200, the dimensionless pressure loss would be approximately 0.65.

[0073] References herein to element positions (e.g., "top," "bottom," "above," "below," etc.) are intended only to describe the orientation of the various elements in the figures. It should be noted that the orientation of the various elements may be different according to other example embodiments, and such variations are intended to be covered by the present disclosure. In addition, the channels formed by one or more surfaces may include a variety of channel cross-sectional shapes, for example, channels having circular, rectangular, elliptical, etc. cross-sectional shapes.

[0074] As used herein, the term "substantially" and similar terms are intended to have a broad meaning that is consistent with the common and accepted usage by those of ordinary skill in the art to which the subject matter of the present disclosure relates. It should be understood by those skilled in the art reviewing the present disclosure that these terms are intended to allow for the description of certain features described and claimed without limiting the scope of such features to the precise numerical ranges provided. Accordingly, these terms should be interpreted as indicating that insubstantial or inconsequential modifications or alterations of the subject matter described and claimed (e.g., within plus or minus 5% of a given angle or other value) are considered to be within the scope of the invention as described in the appended claims. The term "approximately," when applied to values, means plus or minus five percent of the associated value.

[0075] As used herein, the term "coupled" and the like refers to the connection of two components directly or indirectly to one another. Such connection may be fixed (e.g., permanent) or movable (e.g., removable or releasable). Such connection may be achieved by the two components or the two components and any additional intermediate components being integrally formed as a single unitary body with one another, or by the two components or the two components and any additional intermediate components being attached to one another.

[0076] It is important to note that the structure and arrangement of various exemplary embodiments are merely illustrative. Although only a few embodiments are described in detail in the present disclosure, it will be readily appreciated by those skilled in the art who review the present disclosure that many modifications to the flow structure (e.g., changes in the size, dimensions, structure, shape and proportion of various elements, the value of parameters, the installation arrangement, the use of materials, colors, orientations, etc.) are possible without substantially departing from the novel teachings and advantages of the subject matter described herein. For example, an element shown as being integrally formed may be composed of a plurality of parts or elements, the position of the element may be reversed or otherwise changed, and the nature or quantity of the discrete element or position may be modified or changed. According to an optional embodiment, the order or sequence of any process or method steps may be changed or reordered. In addition, as will be appreciated by those of ordinary skill in the art, features from a particular embodiment may be combined with features from other embodiments. Other substitutions, modifications, changes and omissions may also be made in the design, operating conditions and arrangement of various exemplary embodiments without departing from the scope of the present invention.

Claims

1. An axially loaded filter element, comprising: Filter media, a closed first end plate coupled to the filter media at a first filter end and including a handle assembly; an open second end plate coupled to the filter media at a second filter end; and An annular protrusion extends axially from the open second end plate, the annular protrusion having an annular protrusion diameter that is less than 90% of the outer diameter of the filter media.

2. The axially loaded filter element of claim 1, wherein: The handle assembly includes a handle member and a latch that engages an aperture formed in a housing to retain the axially loaded filter element within the housing.

3. The axially loaded filter element of claim 1 , wherein: The annular protrusion comprises an annular protrusion length of at least 10 mm.

4. The axially loaded filter element of claim 1, further comprising a sealing member positioned about the filter media proximate the closed first end plate, the sealing member being configured to engage a cover of a housing to form a substantially fluid-tight seal.

5. The axially loaded filter element of claim 1 further comprising a permeable barrier wrapped around the filter media, the permeable barrier having an average pore size between 20 microns and 200 microns, inclusive.

6. An axially loaded filter element according to any one of claims 1-3 and 4-5, the handle assembly comprising a latch, the latch comprising a tab, the tab being configured to interact with a hole in a cover flange of a cover of a housing to retain the axially loaded filter element within the housing. 7 . The axially loaded filter element of claim 6 , wherein the tab extends away from the latch in a direction away from a longitudinal axis of the axially loaded filter element.

8. The axially loaded filter element of claim 6, wherein the axially loaded filter element is engageable with the cover to form a substantially fluid-tight sealing engagement.

9. The axially loaded filter element of claim 6, wherein the latch includes a gripping member, and wherein the latch is flexible such that actuation of the gripping member releases the tab from the aperture.

10. An axially loaded filter element according to any one of claims 1-5 and 7-9, wherein the annular protrusion has an axial length of at least 25 millimeters.

11. An axially loaded filter element according to any one of claims 1-5 and 7-9, wherein the annular protrusion has an axial length of about 5% of the total axial length of the axially loaded filter element.

12. An axially loaded filter element comprising: Filter media, a closed first end plate coupled to the filter media at a first filter end and including a handle assembly including a latch including a tab configured to interact with an aperture of a cover flange of a cover of a housing to retain the axially loaded filter element within the housing; an open second end plate coupled to the filter media at a second filter end; and An annular protrusion extends axially from the open second end plate.

13. The axially loaded filter element of claim 12, wherein the tab extends away from the latch in a direction away from a longitudinal axis of the axially loaded filter element.

14. The axially loaded filter element of claim 12, wherein the axially loaded filter element is engageable with the cover to form a substantially fluid-tight sealing engagement.

15. The axially loaded filter element of claim 12, wherein the latch includes a gripping member, and wherein the latch is flexible such that actuation of the gripping member releases the tab from the aperture.

16. The axially loaded filter element of claim 12, wherein the annular protrusion has an axial length of at least 25 millimeters.

17. The axially loaded filter element of claim 12, wherein the annular protrusion has an axial length of approximately 5% of the total axial length of the axially loaded filter element.

18. An axially loaded filter element according to any one of claims 12-17, further comprising a sealing member positioned around the filter media proximate the closed first end plate, the sealing member being configured to engage the cover of the housing to form a substantially fluid-tight seal.

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