Patent Description:
Many filter assemblies include a reusable housing holding a filter element or cartridge. Typical filter elements are an elongated cylinder of filter media, often pleated media, with fluid flowing either from the outside through the filter media to a central collection tube, or vice versa. One end is capped with a solid or impermeable end cap and the other end is typically open and attached by O-rings, threads or other such devices to a fluid port of the housing to allow the fluid to either flow to or from the filter element.

In some systems, the closed end cap may have a tapered projection extending away from the rest of the filter element. This tapered projection functions to maintain the alignment of the filter element in the housing during use.

In some systems, the closed end cap may be generally flat. In many systems, there are uses for filter elements with end caps having the tapered projection, as well as uses for filter elements with flat end caps. This means that a user of such a product must order and maintain the correct inventory of filters with the appropriate configuration. <CIT> teaches a detachable alignment fin to be mounted to one end of the cartridge and optionally to use a flat cap attachment. <CIT> suggests an interchangeable mechanism using snap tooth locks for exchanging different types of end caps. <CIT> discloses an end cap coupler system for linking filter cartridges. Linking filter elements are also known from <CIT>, whereby filter elements are threadably mating in metal-to-metal sealing engagement. Similarly, mating filter elements at their fist, respectively second end plate are also disclosed in <CIT>.

These types of filters are often used in the processed food and beverage industry. As such, hygienic factors (clean and sanitary), including the seals and connections used within the filters, are prime considerations.

Improvements in these types of filter assemblies are desirable.

A filter element is provided that improves the prior art.

In general, a filter element is provided comprising: (a) filter media having opposite first and second ends; and (b) an end cap arrangement secured to the first end selectively convertible from a tapered end cap to a flat end cap, and from the flat end cap to the tapered end cap.

The end cap arrangement includes a first end cap secured to the first end; and further including a second end cap secured to the second end.

The end cap arrangement includes the flat end cap secured to the first end cap, and the tapered end cap releasably coupled to the flat end cap.

The filter media includes a cylindrical tube having a central longitudinal axis; and (b) the flat end cap includes a flat, planar surface, perpendicular to the longitudinal axis; and a flat end cap radial wall extending from a perimeter of the planar surface toward the first end cap.

In one or more embodiments, the flat end cap includes an end lip surrounding the flat end cap radial wall such that the flat end cap radial wall extends between the planar surface and the end lip.

In some arrangements, the flat end cap further includes a base plate with an outer periphery; the end lip and flat end cap radial wall projecting away from the base plate; and the base plate is secured to and against the first end cap.

The tapered end cap according to the invention includes a radial wall member surrounding an end piece; the end piece having a tapered projection.

In some examples, the tapered projection is one of a fin, cone, cone-section, or rocket-shape.

One or more embodiments include: (a) the flat end cap radial wall has an exterior surface; (b) the radial wall member of the tapered end cap has an interior surface; and (c) the tapered end cap is releasably coupled to the flat end cap by a coupling arrangement between the exterior surface of the flat end cap radial wall and the interior surface of the tapered end cap.

The coupling arrangement may include a threaded connection.

In some examples, the coupling arrangement includes a lug and a holder engageable upon rotation of the threaded connection.

In one or more embodiments, the lug includes a projection extending from one of the interior surface of the radial wall member and the exterior surface of the flat end cap radial wall; and the holder extends from the other of the interior surface of the radial wall member and the exterior surface of the flat end cap radial wall.

In examples, the lug projects radially inwardly from the interior surface of the radial wall member; and the holder is along the exterior surface of the flat end cap radial wall.

In some embodiments, the lug is projects radially inwardly from adjacent an end rim of the interior surface of the radial wall member; and the holder projects radially outwardly from the end lip and the flat end cap radial wall.

In example arrangements, the lug is an axial projection along the interior surface of the radial wall member; and the holder is along the exterior surface of the flat end cap radial wall.

In one or more embodiments, the threaded connection includes threads along the radial wall member between the lug and an end rim of the interior surface of the radial wall member; and the holder extends from the flat end cap radial wall adjacent to the flat planar surface and includes threads along the flat end cap radial wall between the holder and the base plate.

The holder can include a recess in the flat end cap radial wall, in some embodiments.

In example arrangements, the coupling arrangement includes a plurality of lugs and holders.

In one or more embodiments, the tapered end cap further includes a sealing member at a terminal end of the tapered end cap radial wall member; the sealing member being flexible and positioned to press against the end lip of the flat end cap to form a seal therebetween.

In some embodiments, the tapered end cap further includes a seal tip at a terminal end of the tapered end cap radial wall member; the seal tip being a rubber-like material and positioned to press against the end lip of the flat end cap to form a seal therebetween.

In examples, the tapered end cap includes a tapered projection being one of a fin, cone, cone-section, or rocket-shape.

In some arrangements, the filter media includes a cylindrical tube having a central longitudinal axis; and the flat end cap includes a flat, planar surface, perpendicular to the longitudinal axis; and a flat end cap rim extending from a perimeter of the planar surface away from the first end cap.

In examples, the flat end cap rim includes a plurality of rim segments circumferentially spaced from each other with recesses therebetween.

In some embodiments, the tapered end cap includes a radial wall member surrounding an end piece; the end piece having a tapered projection.

The tapered projection can be one of a fin, cone, cone-section, or rocket-shape.

The tapered end cap may further include a plurality of circumferentially spaced connecting sections extending between the tapered projection and the tapered end cap radial wall member.

The tapered end cap radial wall member can be sized to snap fit over the flat end cap rim.

In some examples, the tapered end cap radial wall member has a radially inward protuberance; and the flat end cap rim has a radially outward projection; wherein the radially inward protuberance snaps over the radially outward projection.

In another aspect, a method of converting an end cap arrangement on a filter element is provided. The method includes (a) providing a filter element having filter media with opposite first and second ends; and an end cap arrangement secured to the first end; and (b)
selectively converting the end cap arrangement from a tapered end cap to a flat end cap, and from the flat end cap to the tapered end cap.

In some examples, the step of selectively converting includes releasably coupling the tapered end cap to the flat end cap.

In some examples, the step of selectively converting includes using a threaded connection between the tapered end cap and flat end cap.

In some examples, the step of selectively converting includes using a lug and a holder engageable upon rotation of the threaded connection.

Some example methods further include forming a seal between the tapered end cap and flat end cap.

In some examples, the step of selectively converting includes using a snap-fit connection between the tapered end cap and flat end cap.

It is noted that not all of the specific features described herein need to be incorporated in an arrangement for the arrangement to have some selected advantage according to the present disclosure.

The reference numeral <NUM>, <FIG>, generally indicates a filter assembly according to the present disclosure. The assembly <NUM> includes a filter base <NUM> to which a filter housing <NUM> is releasably secured. The filter assembly <NUM> is usable to filter fluid, including liquid, air, and steam.

Referring to <FIG> generally the filter base <NUM> includes a fluid flow inlet <NUM> and a fluid flow outlet <NUM>. During operation, fluid to be filtered enters the filter base <NUM> via inlet <NUM>. It is directed into the filter housing <NUM>, for filtering. Filtered fluid is then returned to filter base <NUM> and exits from the filter assembly <NUM> through the fluid outlet <NUM>. Filter assembly <NUM> can be configured for installation and use in a variety of applications including, for example, the processed food and beverage industry. Many applications are possible.

Referring to <FIG>, the filter assembly <NUM> further includes an internally received filter element <NUM>. It is noted that the element is a service part, i.e. it is removable and replaceable within the interior of the housing <NUM>.

The filter element <NUM> includes filter media <NUM>. The filter media <NUM> can be in the form of a cylinder <NUM> with an open interior. The cylinder <NUM> of filter media <NUM> has a central, longitudinal axis <NUM>, extending between a first end <NUM> and second end <NUM>. The filter media <NUM> illustrated is pleated media <NUM>. The pleated media <NUM> can be many different types of media including cellulose, or blends, or polypropylene microfiber media with a graded pore structure, for example.

Surrounding the outer surface of the filter media <NUM> is a rigid support cage <NUM>. The cage <NUM> includes porous openings <NUM>, shown here as diamond shapes or triangulations. The cage <NUM> resists forces that can break or weaken the element <NUM>, and also better withstands pressure differential across the filter during high volumes of fluid processing.

At the first end <NUM> of the filter element <NUM> is an end cap arrangement <NUM> including a first end cap <NUM> secured to the first end <NUM>. The end cap arrangement <NUM> is selectively convertible from a tapered end cap <NUM> to a flat end cap <NUM>, and from the flat end cap <NUM> to the tapered end cap <NUM>. Example end cap arrangements <NUM> are discussed in detail below.

At the second end <NUM> of the filter element <NUM> is a second end cap <NUM> secured to the second end <NUM>. In the example shown, the second end cap <NUM> is an open end cap <NUM>. The second end cap <NUM> typically releasably attaches to the filter base <NUM>, and can include one or more seal members <NUM> to form a seal with the filter base <NUM>.

During operation, fluid to be filtered enters the filter base <NUM> via inlet <NUM>. It is directed into the interior of the cylinder of the filter element <NUM>, passes through the filter media <NUM> where it is filtered. The filtered fluid flows into the space between the cage <NUM> and the filter housing <NUM>, and is then returned to filter base <NUM> and exits from the filter assembly <NUM> through the fluid outlet <NUM>.

In reference now to <FIG>, a first embodiment of end cap arrangement <NUM> is shown. <FIG> shows a perspective view of the end cap arrangement <NUM>, having the tapered end cap <NUM> releasably coupled to the flat end cap <NUM>. <FIG> is a bottom, perspective view of the tapered end cap <NUM>, and <FIG> is an upper, perspective view of the flat end cap <NUM>.

In <FIG>, the flat end cap <NUM> includes a flat, planar surface <NUM>, perpendicular to the longitudinal axis <NUM> of the filter media <NUM>. The planar surface <NUM> is shown to have a round outer perimeter <NUM>. A flat end cap radial wall <NUM> extends from the perimeter <NUM> of the planar surface <NUM> toward the first end cap <NUM> to form an upright surrounding wall <NUM>. The radial wall <NUM> has an exterior surface <NUM>.

In this example, the flat end cap <NUM> includes an end lip <NUM> surrounding the flat end cap radial wall <NUM> such that the flat end cap radial wall <NUM> extends between the planar surface <NUM> and the end lip <NUM>.

The flat end cap <NUM> further includes a base plate <NUM> with and outer periphery <NUM>. The base plate <NUM> can be flat such that the end lip <NUM> and flat end cap radial wall <NUM> project away from the base plate <NUM> and away from the first end cap <NUM>. The base plate <NUM> can be secured to and against the first end cap <NUM>.

<FIG> shows the tapered end cap <NUM>, which includes a radial wall member <NUM> surrounding an end piece <NUM>. The end piece <NUM> has a tapered projection <NUM>. The tapered projection <NUM> can be any one of a fin, cone, cone-section, or rocket-shape member.

In the non-limiting example shown in <FIG>, the tapered projection <NUM> has an upper conical section <NUM>, with a first cylindrical wall <NUM> extending from the conical section <NUM> toward the first end cap <NUM>. A plurality of circumferentially spaced fins <NUM> project radially from the first wall <NUM>. In the example shown, there are <NUM> fins <NUM>. The fins <NUM> can help to orient the tapered end cap <NUM> into the filter housing <NUM>.

Extending from the wall <NUM> toward the first end cap <NUM> is a second cylindrical wall <NUM>. The second wall <NUM> has a larger diameter than the first wall <NUM>.

Circumscribing the second wall <NUM> at a free, terminal end of the second wall <NUM> is a sealing member <NUM>. The sealing member <NUM> is generally a flexible member positioned to press against the flat end cap <NUM> to form a seal therebetween.

Attention is directed to <FIG>. In <FIG>, the sealing member <NUM> has a bendable tip <NUM> for preventing leakage inside of the tapered end cap <NUM>. Along an inside surface of the sealing member <NUM> is an internally projecting inner seal member <NUM>. The inner seal member <NUM> presses against the end lip <NUM> of the flat end cap <NUM> to help prevent leakages inside of the tapered end cap <NUM>.

Also shown in <FIG> is an inwardly projecting surface <NUM>, extending inwardly between the second wall <NUM> and the first wall <NUM> (<FIG>). The surface <NUM> engages against the flat planar surface <NUM> of the flat end cap <NUM>, to help ensure a good match between the flat end cap <NUM> and the tapered end cap <NUM>.

An alternative embodiment is shown in <FIG>. In <FIG>, the releasable seal between the flat end cap <NUM> and the tapered end cap <NUM> is formed with a seal tip <NUM> at the terminal end of the radial wall member <NUM>, in this example, at the end of the second wall <NUM>. The seal tip <NUM> can be bi-injected and be a soft based rubber-like material, such as EPDM, silicone, etc. The seal tip <NUM> is positioned to press against the end lip <NUM> of the flat end cap <NUM> to form a seal therebetween.

In reference now to <FIG>, and <FIG>, the tapered end cap <NUM> and the flat end cap <NUM> are releasably coupled together by a coupling arrangement <NUM>. Many embodiments are possible.

In the example shown, the coupling arrangement <NUM> is between the exterior surface <NUM> of the radial wall <NUM> of the flat end cap <NUM> and an interior surface <NUM> of the radial wall member <NUM> of the tapered end cap <NUM>.

The coupling arrangement <NUM>, in the non-limiting example shown, includes a threaded connection <NUM>. Threads <NUM> are along the exterior surface <NUM> of the radial wall <NUM>, and mating threads <NUM> are along the interior surface <NUM> of the second wall <NUM> to provide a rotational threaded fit between the tapered end cap <NUM> and flat end cap <NUM>.

The coupling arrangement <NUM> can include a projecting lug <NUM> and a holder <NUM> engageable upon rotation of the threaded connection <NUM>. The projecting lug <NUM> includes a radial projection <NUM> extending from one of the interior surface <NUM> of the radial wall member <NUM> and the exterior surface <NUM> of the flat end cap radial wall <NUM>. The holder <NUM> includes an L-shaped radial projection <NUM> extending from the other of the interior surface <NUM> of the radial wall member <NUM> and the exterior surface <NUM> of the flat end cap radial wall <NUM>.

In the example shown in <FIG>, the projecting lug <NUM> projects from the interior surface <NUM> of the second wall <NUM> of the radial wall member <NUM>. For example, the lug <NUM> is shown to be along an end rim <NUM> of the interior surface <NUM> of the radial wall member <NUM>.

The L-shaped projection <NUM> extends from the exterior surface <NUM> of the flat end cap radial wall <NUM>. One end of the L -shaped projection <NUM> extends from the end lip <NUM>, bends at a generally right angle spaced from the end lip <NUM>, and includes a section <NUM> generally parallel to the flat planar surface <NUM>. An end of the section <NUM> includes a projecting hook <NUM> for engaging the lug <NUM>. See <FIG>, in which the hook <NUM> is over the lug <NUM>.

In some examples, the coupling arrangement <NUM> may include a plurality of either or both projecting lugs <NUM> and holders <NUM>.

In reference now to <FIG>, a second embodiment of end cap arrangement <NUM> is shown. <FIG> is a bottom, perspective view of the tapered end cap <NUM>, and <FIG> is an upper, perspective view of the flat end cap <NUM>. <FIG> show enlarged views of coupling arrangement <NUM>. The coupling arrangement <NUM> is similar to the embodiment of <FIG>, with the difference being the location of the projecting lug <NUM> and holder <NUM>, as well as the shape of the lug <NUM> and holder <NUM>. In this embodiment, the lug <NUM> is spaced away from the end rim <NUM>, and the holder <NUM> is spaced away from the end lip <NUM>. That is, the lug <NUM> and holder <NUM> are located toward the upper part of the coupling arrangement <NUM> (as contrasted with <FIG>, where they are toward the bottom or lower part of the coupling arrangement <NUM>), when the end cap arrangement <NUM> is oriented with the tapered end cap <NUM> pointing up. Injection molding can be a more convenient and less expensive process with the lug <NUM> and holder <NUM> located in the upper part rather than the lower part.

The lug <NUM> includes a protrusion <NUM> and a projecting stopper <NUM> circumferentially spaced apart from each other. The holder <NUM> is along the exterior surface <NUM> of the flat end cap radial wall <NUM>. In this example, the holder <NUM> projects radially outwardly from the exterior surface <NUM>. In use, the holder <NUM> slides over the protrusion <NUM> and is stopped from further movement by the stopper <NUM>.

The description of the rest of the second embodiment is as described above and incorporated herein by reference, using the same reference numerals.

<FIG> show a third embodiment of end cap arrangement <NUM>. <FIG> is a bottom, perspective view of the tapered end cap <NUM>, and <FIG> is an upper, perspective view of the flat end cap <NUM>. <FIG> show enlarged views of the coupling arrangement <NUM>. The coupling arrangement <NUM> is located in generally the same position as the embodiment of <FIG> (i.e., in the upper part of the coupling arrangement <NUM>, spaced away from the end rim <NUM> and end lip <NUM>), while the geometry of the lug <NUM> and holder <NUM> are somewhat different. In this embodiment, the holder <NUM> includes a recess <NUM>. The lug <NUM> includes an axial projection/ protrusion <NUM>, and slides over the holder <NUM> and into the recess <NUM>.

The description of the rest of the third embodiment is as described above for <FIG> and incorporated herein by reference, using the same reference numerals.

In the example embodiments of <FIG> and <FIG>, the lug <NUM>, <NUM> is along the interior surface <NUM> of the radial wall member <NUM>, and the holder <NUM>, <NUM> is along the exterior surface <NUM> of the flat end cap radial wall <NUM>. In some cases, the holder <NUM> includes recess <NUM> within the exterior surface <NUM> of the flat end cap radial wall.

Optionally, the threaded connection <NUM> includes threads <NUM> along the interior surface <NUM> of the radial wall member <NUM> between the lug <NUM>, <NUM> and the end rim <NUM> of the interior surface <NUM> of the radial wall member <NUM>. Optionally, the holder <NUM>, <NUM> is along the flat end cap radial wall <NUM> adjacent to the flat planar surface <NUM> and spaced from base plate <NUM>, with threads <NUM> being between the holder <NUM>, <NUM> and the base plate <NUM>.

In reference now to <FIG>, another embodiment of end cap arrangement is illustrated at <NUM>'. <FIG> is a perspective view of end cap arrangement <NUM>' having tapered end cap <NUM>' releasably coupled to the flat end cap <NUM>'. <FIG> is an upper perspective view of the tapered end cap <NUM>', and <FIG> is an upper, perspective view of the flat end cap <NUM>'.

The flat end cap <NUM>' includes flat, planar surface <NUM>', perpendicular to the longitudinal axis <NUM> of the cylinder <NUM> of filter media <NUM>. A flat end cap rim <NUM> extends from perimeter <NUM>' of the planar surface <NUM>' away from the first end cap <NUM>.

The flat end cap rim <NUM> includes a plurality of rim segments <NUM> circumferentially spaced from each other with recesses (gaps) <NUM> therebetween. In the example shown, there are <NUM> rim segments <NUM>, evenly spaced about the perimeter <NUM>', with one recesses <NUM> in between two adjacent segments <NUM>. The rim segments <NUM> circumscribe the planar surface <NUM>' and are angled at a non-zero angle relative to the surface <NUM>', extending away from the first end cap <NUM> on the first end <NUM> of the filter media <NUM>.

The flat, planar surface <NUM>' may include ornamentation and/or branding <NUM> to provide an attractive, eye-catching and distinctive appearance to the flat end cap <NUM>'.

<FIG> shows the tapered end cap <NUM>', which includes radial wall member <NUM>' surrounding end piece <NUM>'. The end piece <NUM>' has tapered projection <NUM>'. The tapered projection <NUM>' can be any one of a fin, cone, cone-section, or rocket-shape member.

In the non-limiting example shown in <FIG>, the tapered projection <NUM>' has a plurality of radially extending fins <NUM> projecting radially from a centerpoint <NUM> of the tapered projection <NUM>'. In the example shown, there are <NUM> fins <NUM>. The fins <NUM> can help to orient the tapered end cap <NUM>' into the filter housing <NUM>. The fins <NUM> are each trapezoid shaped, including a slanting edge <NUM> angled upwardly, as the edge <NUM> extends from adjacent the radial wall member <NUM>' to the centerpoint <NUM>.

The tapered end cap <NUM>' further includes a plurality of circumferentially spaced connecting sections <NUM> extending between the tapered projection <NUM>' and the tapered end cap radial wall member <NUM>'. The connecting sections <NUM> join or connect a base of each of the fins <NUM> to the radial wall member <NUM>'.

Spaced between adjacent connecting sections <NUM> are openings <NUM>. The openings <NUM> allow for drainage of any moisture from the tapered end cap <NUM>' to the flat end cap <NUM>'.

The tapered end cap <NUM>' is constructed and arranged to removably attach to the flat end cap <NUM>'. In examples, the radial wall member <NUM>' of the tapered end cap <NUM>' is sized to rotate or snap fit over the flat end cap rim <NUM>.

Attention is directed to the embodiment of <FIG>, showing a cross-section of the end cap arrangement <NUM>'. In this non-limiting example, the tapered end cap radial wall member <NUM>' has a radially inward protuberance <NUM>. The flat end cap rim <NUM> has a radially outward projection <NUM>. The radially inward protuberance <NUM> of the tapered end cap <NUM>' snaps over the radially outward projection <NUM> of the flat end cap <NUM>'.

The above parts and assemblies can be used in a method of converting an end cap arrangement on a filter element. For example, the method can be used for end cap arrangement <NUM>, <NUM>' on filter element <NUM>.

The method includes providing filter element <NUM> having filter media <NUM> with opposite first <NUM> and second <NUM> ends, in which end cap arrangement <NUM>, <NUM>'secured to the first end <NUM>. The method includes selectively converting the end cap arrangement <NUM>, <NUM>' from tapered end cap <NUM>, <NUM>' to flat end cap <NUM>, <NUM>', and from the flat end cap <NUM>, <NUM>' to the tapered end cap <NUM>, <NUM>'.

The step of selectively converting includes releasably coupling the tapered end cap <NUM>, <NUM>' to the flat end cap <NUM>, <NUM>'.

The step of selectively converting can include using threaded connection <NUM> between the tapered end cap <NUM> and flat end cap <NUM>.

The step of selectively converting can include using lug <NUM> and holder <NUM> engageable upon rotation of the threaded connection <NUM>.

The method can further include forming a seal between the tapered end cap <NUM> and flat end cap <NUM>. This may involve using sealing member <NUM> and/or surface <NUM> on the flat end cap <NUM>; or, using seal tip <NUM> on the flat end cap <NUM>.

Claim 1:
A filter element (<NUM>) comprising:
(a) filter media (<NUM>) having opposite first and second ends (<NUM>, <NUM>); the filter media (<NUM>) including a cylindrical tube (<NUM>) having a central longitudinal axis;
(b) an end cap arrangement (<NUM>, <NUM>') includes a first end cap (<NUM>,<NUM>') secured to the first end (<NUM>); the end cap arrangement selectively convertible from a tapered end cap (<NUM>, <NUM>') to a flat end cap (<NUM>, <NUM>'), and from the flat end cap (<NUM>, <NUM>') to the tapered end cap (<NUM>, <NUM>');
(i) wherein the tapered end cap (<NUM>, <NUM>') includes a radial wall member (<NUM>, <NUM>') surrounding an end piece (<NUM>, <NUM>'); the end piece (<NUM>, <NUM>') having a tapered projection (<NUM>, <NUM>') extending away from the rest of the filter element;
(ii) the flat end cap (<NUM>, <NUM>') includes a flat, planar surface (<NUM>, <NUM>'), perpendicular to the longitudinal axis; and a flat end cap radial wall (<NUM>) extending from a perimeter of the planar surface (<NUM>, <NUM>') toward the first end cap (<NUM>, <NUM>');
(c) a second end cap (<NUM>) secured to the second end (<NUM>); the second end cap being an open end cap; characterized in that:
the end cap arrangement (<NUM>, <NUM>') includes the flat end cap (<NUM>, <NUM>') secured to the first end cap (<NUM>, <NUM>'), and the tapered end cap (<NUM>, <NUM>') releasably coupled to the flat end cap (<NUM>, <NUM>').