Oval filter with exterior elliptical radial seal and internal support structure

Various embodiments relate to a filter element. The filter element includes a first endplate that defines a first endplate opening and a second endplate. Filter media is positioned between and extending axially between the first endplate and the second endplate. The filter media defines a central opening extending axially therein. A support structure is disposed within the central opening of the filter media and is attached to the first endplate and the second endplate. The support structure includes an axial lobed extension that extends from a first end of the support structure to a second end of the support structure. The support structure is configured to resist collapse of the filter element.

TECHNICAL FIELD

The present application relates to filtration systems. More particularly, the present application relates to fluid filtration systems having a replaceable filter element.

BACKGROUND

Internal combustion engines generally combust a mixture of fuel (e.g., gasoline, diesel, natural gas, etc.) and air. Lubrication oil is also supplied to the engine to lubricate the various moving components of the engine. Either prior to entering the engine or during engine operation, the intake air, fuel, lubrication oil, and other fluids are typically passed through filtration systems to remove contaminants (e.g., dust, water, oil, etc.) from the fluids. The filtration systems include filter elements having filter media. As the fluid passes through the filter media, the filter media removes at least a portion of the contaminants in the fluid.

The filter elements (e.g., filter cartridges) often include a seal member that is compressed against a component of the filtration system housing or another portion of the filtration system. Proper sealing in such systems is important to maintain system efficiency in order to meet emission regulations and provide suitable protection to an engine. That is, proper sealing is needed to maintain separation between “dirty” and “clean” sides of a filter used in such systems. The filter element and sealing element may include shapes that, when the axial length of the filter element increases, cause the filter element to collapse under certain filtration conditions.

SUMMARY

Various embodiments relate to a filter element. The filter element includes a first endplate that defines a first endplate opening and a second endplate. Filter media is positioned between and extending axially between the first endplate and the second endplate. The filter media defines a central opening extending axially therein. A support structure is disposed within the central opening of the filter media and is attached to the first endplate and the second endplate. The support structure includes an axial lobed extension that extends from a first end of the support structure to a second end of the support structure. The support structure is configured to resist collapse of the filter element.

Another example embodiment relates to a filtration system. The filtration system includes a housing and a filter element positioned within the housing. The filter element includes a first endplate that defines a first endplate opening and a second endplate. Filter media is positioned between and extending axially between the first endplate and the second endplate. The filter media defines a central opening extending axially therein. A support structure is disposed within the central opening of the filter media and is attached to the first endplate and the second endplate. The support structure includes an axial lobed extension that extends from a first end of the support structure to a second end of the support structure. The support structure is configured to resist collapse of the filter element.

DETAILED DESCRIPTION

Referring to the figures generally, various embodiments disclosed herein relate to a filtration system with a filter element that includes a unique sealing configuration between a filter element and a housing and an internal support structure within the filter element that inhibits collapse of the filter element during operation. The seal interface is provided between one end of a filter element and one end of a mating head or component of a housing. The filter element has an elliptical shaped extension with a gasket around its outer perimeter. For the mating component, a housing has a portion with an elliptical shaped portion to seal against the elliptical shaped extension of the filter element. The seal interface described herein can provide a keying feature which can be helpful to ensure that the correct filter element is being installed and can help make installation easier. Accordingly, the filter element with the elliptical sealing configuration allows for a wide variety of filter element designs that includes different shapes and sizes and, due to the elimination of flat section in the seal zone, provides improved sealing between the housing and filter element. An internal support structure within the filter element provides resistance to the filter element collapse, thereby allowing for larger aspect ratios of the filter element (e.g., longer and narrower). As will be appreciated, as the aspect ratio of the filter element increases, the stress on the filter media and filter element increases, as does the risk of filter element collapse. Beneficially, the internal support structure includes axial lobed support members and cross members that provide support against filter element collapse during operation.

As used herein, the term “elliptical” refers to a shape that is a mathematically true ellipse: a closed plane curve generated by a point moving in such a way that the sums of its distances from two fixed points is a constant. As will be appreciated, features described as elliptical, for example the elliptical protruding member, may have different circular shapes in alternative embodiments. The term “oval” refers to a shape that has a rounded and slightly elongated outline or shape, for example the shape similar to an egg. Additionally, “oval” refers to a “racetrack” shape that is two hemispherical portions that are mirrored and two substantially parallel straight surfaces that connect the hemispherical portions.

Referring toFIGS. 1A and 1B, an exploded and perspective view of a filter element100that includes an elliptical protruding member110and an internal support structure108is shown, according to an example embodiment. The filter element100includes a first endplate102that includes the elliptical protruding member110, a second endplate106, filter media104, and the internal support structure108disposed between the first endplate102and the second endplate106and disposed within the filter media104. The filter element100may be a cylindrical filter element with similarly shaped components. As will be appreciated, the filter element100may be installed in an interior compartment of a housing that has a similar elliptical shape or another shape that can receive the shape and size of the filter element100and/or attached to a filter head. In some arrangements, the filter element100is connected to a filter mounting head, and a housing is also attached to the filter mounting head (e.g., via a threaded connection in arrangements where the housing is a spin-on housing).

The filter media104is positioned between and extending axially between the first endplate102and the second endplate106. The filter media defines a central opening105that extends axially therein. As shown inFIGS. 1A-1C, the filter media104is racetrack shaped, however a wide variety of shapes, including non-round configurations or differing aspect ratios may be implemented. In some embodiments, the filter media104has a non-round configuration with an aspect ratio between 0.20 and 0.30 (e.g., min/max). The filter media104includes an inner clean (e.g., filtered fuel) side and an outer dirty (e.g. unfiltered fuel) side. Accordingly, the filter element100is an outside-in flow filter element. In an alternative arrangement, the filter element100is an inside-out flow filter element having an inner dirty side and an outer clean side. Fluid to be filtered passes from the dirty side of the filter media104to the clean side of the filter media104. The filter media104may include any of paper-based filter media, fiber-based filter media, foam-based filter media, pleated filter media, or the like. Pleated filter media refers to filter media that is folded along a plurality of bend lines extending axially along an axial direction between an upstream inlet and a downstream outlet. In some embodiments, a flat sheet of filter media is alternately folded along a plurality of pleat fold lines, thereby defining a pleat block. The pleated filter media may include a plurality of wall segments extend in serpentine manner between the bend lines and define axial flow channels therebetween.

The first endplate102may include a plurality of retention tabs to secure the filter element100to a filter mounting head of a filtration system when the filter element100is installed in the filtration system. As shown inFIG. 1A, the first endplate102is coupled to a first, top end of the filter media104and is an open endplate including an opening116. The first endplate102includes a first end surface114and a second end surface115spaced axially from the first end surface114. The first end surface114includes the elliptical protruding member110extending axially from the first end surface114in a direction away from the filter media104. The elliptical protruding member110substantially surrounds the opening116. Generally, the elliptical protruding member110is disposed on the first endplate102and is configured to engage a housing or a filter mounting head (not shown). In particular embodiments, the elliptical protruding member110may have an aspect ratio of 0.35 and 0.40 (e.g., min/max). The ellipse shape of the elliptical protruding member110eliminates flat sections in the urethane seal zone, which can be difficult to create a seal with. When the filter element100is installed within a housing, the elliptical protruding member110forms an elliptical radial seal between the housing and the filter element100, thereby preventing fluid from bypassing the filter element100. As will be appreciated, the shape of the first endplate102may be a different shape from the elliptical protruding member110. For example, and as shown in the top view of the first endplate102ofFIG. 2, the elliptical protruding member110is an elliptical shape and the first endplate102is a racetrack shape.

An elliptical seal member118is disposed about an outer surface of the elliptical protruding member110. The elliptical seal member118is configured to provide a seal interface between the filter element100and the mating head (e.g. housing). One function of the elliptical seal member118is to provide sealing between the “dirty” and “clean” sides of the filter element. As shown, the elliptical protruding member110protrudes from the first endplate102such that the elliptical seal member118is positioned along an “insertion axis” to ensure sealing capability between the two components. The insertion axis refers to the sealing location when the elliptical protruding member110is inserted into a similar shaped elliptical portion in the mating head.

In some embodiments, an elliptical gasket is partially disposed in the elliptical seal member118of the elliptical protruding member110. In one embodiment, the elliptical gasket is overmolded onto the elliptical protruding member110. In other embodiments, the elliptical seal member118is a slip-on gasket that may be attached to the elliptical protruding member110through an interference fit between the elliptical seal member118and elliptical protruding member110. The elliptical gasket further provides a low insertion force while maintaining a robust joint and sealing surface between the filter element100and a housing. In some embodiments, the ellipticaal seal member118is configured to provide an easy insertion gasket shape since the portion of gasket engagement against insertion depth would be a continuous and smoothly varying function. In other words, the continuous and smoothly varying shape of the elliptical seal member118can help make installment and servicing of the filter element100easier.

In some embodiments, the elliptical seal member118may include at least one peak and/or oscillating configuration. The peak is a raised portion that extends axially away from the first end surface114of the first endplate102and toward the end of the elliptical protruding member110. The peak structure can allow for an even lower insertion force during the initial engagement between the filter element100and a receptive housing. In some embodiments, the peak structure is configured and arranged with projecting tangent arcs in a wave pattern around the surface of the elliptical protruding member110. Such a shape of the elliptical seal member118can create a continuous curvature. For example, a first peak and a second peak are oppositely disposed on sides of the elliptical seal member118in an outline of a hyperbolic paraboloid or outline of a “saddle” surface. The hyperbolic paraboloid may be employed to provide a gradual increase in insertion force as opposed to an abrupt increase caused by flat sections.

The filter element100further includes a second endplate106coupled to a second, bottom end of the filter media104. As shown inFIG. 1A, the second endplate106is a closed endplate. In some embodiments, the second endplate106is an open endplate that includes a central opening sized and shaped to receive a component of a filtration system (e.g., a standpipe) when the filter element100is installed in an operating position within the filtration system.

Turning toFIG. 1C, a cross-sectional view of the filter element100is shown. The cross-sectional view shows portions of the plurality of axial lobed extensions120and a plurality of cross-ribs122of the internal support structure108. As shown inFIG. 1C, the plurality of axial lobed extensions120include a first axial lobed extension134and a second axial lobed extension136. Each axial lobed extension extends from a first end of the internal support structure126to a second end of the internal support structure128. The first axial lobed extension134is axially spaced away from the second axial lobed extension136. Each cross-rib in the plurality of cross-ribs122extends radially around a perimeter of the internal support structure108and each cross rib axially displaced from an adjacent cross rib. As shown inFIG. 1C, the first end of the internal support structure126is configured to position adjacent to and/or with the first endplate102. Additionally, the second end of the internal support structure128is configured to position adjacent to and/or with the second endplate106. The internal support structure108is expanded in greater detail below in relation toFIGS. 3A and 3B. In some embodiments, the plurality of axial lobed extensions120may comprise an axial extending portion with non-lobed (e.g., substantially straight) portions that extend axially between at least one lobed portion and an end of the internal support structure108. In other embodiments, the axial lobed extensions may extend in substantially the same direction with respect to the central axis of the filter element100. The lobed extensions may comprise flared or substantially straight protrusions that extends away from a central axis of the axial lobed extension.

Referring toFIG. 3A, a perspective view of the internal support structure108of the filter element100ofFIG. 1A. Additionally,FIG. 3Bshows a perspective view of a first axial lobed extension134of the internal support structure108ofFIG. 3A. The internal support structure108includes the first end of the internal support structure126, the second end of the internal support structure128, a first axial support130, and a second axial support132. In some embodiments, the internal support structure108is a plastic interbody that is molded to form the various elements of the internal support structure108(e.g., it is a single, integral unit). In other embodiments, the interbody of the internal support structure108is made of a metal alloy (e.g., steel). As will be appreciated, the plastic interbody provides a variety of advantages over a metal alloy interbody including ease of molding, lower cost, wider variety of seal areas, and greater design efficiency.

As shown best inFIGS. 1B and 3A, the first axial lobed extension134and the second axial lobed extension136define three “sections” of the filter element100. The first section is defined by the first axial support130and the first axial lobed extension134, the second section is defined by the first axial lobed extension134and the second axial lobed extension136, and the third section is defined by the second axial lobed extension136and the second axial support132. The first axial lobed extension134and the second axial lobed extension136are configured to encourage cross flow between the various sections (defined by the first axial lobed extension134and the second axial lobed extension136) of the filter element100.

As shown inFIG. 3A, the first end of the internal support structure126includes an elliptical extension143configured to engage the elliptical protruding member110of the first endplate102. In some embodiments, the elliptical protruding member110is molded onto the first end of the internal support structure126as one integral unit. The first axial support130and the second axial support132each extend from the inner diameter (e.g., around the opening116of the first endplate102) of the first end of the internal support structure126towards the second end of the internal support structure128at a respective pole of the hemispherical portions. As will be appreciated, the first end of the internal support structure126, the second end of the internal support structure128, the first axial support130, and the second axial support132form the skeleton of the internal support structure108. Around the perimeter of the internal support structure108(e.g., lining up with the perimeter of the second end of the internal support structure128and the first axial support130and the second axial support132) the plurality of cross-ribs122provide radial support and structure to the filter element100by way of the internal support structure108. As shown inFIG. 3A, each set of cross-ribs in the plurality of cross ribs includes two concentric, cross-rib bands148connected by a plurality of axial connecting ribs150. In some embodiments, each cross-rib band148is connected to a lobe of the axial lobed extensions120.

The first axial lobed extension134includes a first set of laterally extending lobes138and a second set of laterally extending lobes140. As shown inFIG. 3B, each lobe in the first set of laterally extending lobes138extends in a lateral direction (e.g., x-axis) relative to the axial direction (e.g., y-axis). Each lobe in the first set of laterally extending lobes138is axially spaced from another lobe in the first set of laterally extending lobes138, such that a lobe in the second set of laterally extending lobes140is disposed between each lobe in the first set of laterally extending lobes138. Each lobe in the second set of laterally extending lobes140extends in the lateral direction in a direction relative to the axial direction that is opposite from the first set of laterally extending lobes138. In other words, the first set of laterally extending lobes138and the second set of laterally extending lobes140are substantially mirrored about the central axis160(e.g., y-axis) of the first axial lobed extension134. The connection of the first set of laterally extending lobes138and the second set of laterally extending lobes140(which is mirrored about the central axis160) defines an undulating pattern along both sides of the first axial lobed extension134. In some embodiments, the first set of laterally extending lobes138and/or the second set of laterally extending lobes140may be mirrored about the central axis160at different locations and/or angles to facilitate cross flow between different sections of the filter element100. For example, a lobe in the first set of laterally extending lobes138is angled at a substantially 45-degree angle toward the center of the internal support structure108such that a substantially 90-degree angle is formed along first axial lobed extension134. In other embodiments, each lobe in the first set of laterally extending lobes138includes a first angled portion302, a second angled portion304, and a flat portion306disposed between the first angled portion302and the second angled portion304. The first angled portion302and the second angled portion304are angled at a substantially 45-degree angle toward the center of the support structure108in opposite directions (although the precise angle may vary). The flat portion306is substantially parallel to the center of the support structure108. Each lobe in the second set of laterally extending lobes140may include a mirrored version (about the central axis160) of the first angled portion302, second angled portion304, and flat portion306.

The first set of laterally extending lobes138and the second set of laterally extending lobes140are joined at a connection plane158along a lateral axis (e.g., substantially parallel to the x-axis). The connection plane158is the transition from the first set of laterally extending lobes138to the second set of laterally extending lobes140. In some embodiments, the connection plane158may be diagonally orientated (e.g., angled between the x-axis and/or y-axis) depending on the orientation of each lobe. The connection plane158of the first axial lobed extension134with the first end of the internal support structure126and the second end of the internal support structure128is substantially parallel to the x-axis. As will be appreciated, one or both ends of the first axial lobed extension134may be a partially formed first set of laterally extending lobes138or a partially formed second set of laterally extending lobes140.

Each lobe in the first set of laterally extending lobes138has a first flared portion142that extends in the z-axis with respect to the y-axis. In some embodiments, the first flared portion142is angled away from (e.g., perpendicular to) the central axis160from one connection plane158to another connection plane158on the same lobe. Similarly, each lobe in the second set of laterally extending lobes140has a second flared portion144that extends in the z-axis with respect to the y-axis in a direction that is opposite to the first flared portion142. In some embodiments, the second flared portion144is angled away from (e.g., perpendicular to) the central axis160from one connection plane158to another connection plane158on the same lobe. In other embodiments, the first flared portion142and the second flared portion144extend in the same direction in the z-axis with respect to the y-axis. The first flared portion142and the second flared portion144may include a wide variety of orientations, sizes, and configuration to promote cross flow between the sections defined in the filter element100.

Referring toFIGS. 4A and 4B, a perspective and cross-sectional view of a filtration system400a filter element402with an elliptical protruding member110and an internal support structure108is shown, according to an example embodiment. The filter element402is similar to the filter element100described inFIGS. 1A-1C. A difference between the filter element402and the filter element100, is the filter element402has the width and length to fit into the housing404of the filtration system400. Accordingly, similar elements between the filter element402and filter element100will have similar numbering.

The housing404has a first housing end410having a housing opening414, a second housing end412, and an outlet416. The housing404is releasably connected to the filter element402. As one example, the filter element402is inserted in an axial direction to mount onto the housing404. The housing404has a mounting component that includes an elliptical boss408that surrounds the first housing end410. When the filter element402is connected to the housing404, the housing opening414is in fluid communication with the opening116of the first endplate102of the filter element100. The elliptical boss408mates with the elliptical protruding member110and forms a seal with the elliptical seal member118. In use, for example, the filter element100is connected to the housing404when the elliptical protruding member110is inserted into the elliptical boss408, such that the elliptical boss408surrounds the elliptical protruding member110and elliptical seal member118, and a radially directed seal is formed. As described above, the elliptical seal member118may include an elliptical gasket that provides improved sealing between the filter element402and the housing404. In some embodiments, the elliptical boss408of the housing404can have a shoulder that abuts the first end surface114of the first endplate102.

In some embodiments, the elliptical boss408and the elliptical protruding member110can provide a keying feature to ensure that the correct filter element402is being installed into the housing404. For example, a plurality of tabs around the elliptical protruding member110(or in some cases on the first end surface114) of the first endplate102engage with a complementary plurality of slots in the elliptical boss408(or in some cases on the first housing end410) of the housing404. This tab and slot configuration can help orient and “key” the filter element402within the housing404to further help insure that the correct filter element is being installed into the filtration system400. In other embodiments, the elliptical boss408includes a side opening formed in a wall of the elliptical boss408and the elliptical protruding member110includes an anchor portion that is configured to engage an inner diameter of the elliptical boss408. The anchor point provides a keying feature and an additional locking feature when the anchor portion is retained in the elliptical boss408.

It should be noted that any use of the term “exemplary” herein to describe various embodiments is intended to indicate that such embodiments are possible examples, representations, and/or illustrations of possible embodiments (and such term is not intended to connote that such embodiments are necessarily extraordinary or superlative examples).

It is important to note that the construction and arrangement of the various exemplary 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, values of 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. Additionally, features from particular embodiments may be combined with features from other embodiments as would be understood by one of ordinary skill in the art. Other substitutions, modifications, changes and omissions may also be made in the design, operating conditions and arrangement of the various exemplary embodiments without departing from the scope of the present invention.