DESC:1
FILTER ELEMENT
FIELD OF THE INVENTION
[0001] The present invention relates generally to a filter element. More particularly, the present invention relates to a filter element having a central support tube.
DESCRIPTION OF THE RELATED ART
[0002] A filter element of tubular type that is disposable after a selected period of use is well known in the art. The filter element usually comprises a cylindrical shaped filter media through which fluid enters radially from outside inward, and cleaned fluid is then discharged axially.
The filter media is arranged between two endcaps. In the filter element, a centre tube is integrated as a supporting body that forms a wall of an axial inner space through which the cleaned fluid is derived. The end caps which are preformed from plastic material and attached by a variety of means to the ends of the filter element. The end caps embrace the ends of the filter element and at least one of the endcaps is provided with a suitable opening for permitting the discharge of cleaned fluid from the centre tube.
[0003] In existing filter elements, both ends of the tubular frame are embedded in the endcaps. The endcaps have to made of thick size in order to embed the ends of the tubular frame, thereby
increasing manufacturing and material costs for preparation of the endcaps. If one end of the tubular frame is not embedded in the endcaps to reduce thickness of an endcap, the tubular frame cannot withstand axial and radial pressures on the filter element. [0004] In light of the foregoing, there exists a need for a filter element with end caps of less thickness. Moreover, there exists a need for a filter element that can withstand radial and axial pressures with thin endcaps.
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OBJECTS OF THE INVENTION
[0005] An object of the present invention is to provide a thin endcap of a filter element without any effect on stability and strength of filter element.
[0006] Another object of the present invention is to provide radial stability to a tubular frame of the filter element. [0007] Yet another object of the present invention is to provide a reinforcing member to prevent collapse of a filter media of the filter element under excessive pressure.
SUMMARY OF THE INVENTION
[0008] The present invention provides a design of a filter element. The filter comprises a filter media with a hollow inner surface. The filter has a first end cap secured to a top end and a second endcap secured at a bottom end, respectively. The filter further has a tubular frame, having a first end and a second end, disposed in the hollow inner surface of the filter media.
The tubular frame has a perforated outer wall which extends axially along the hollow inner surface of the filter media. The length of the tubular frame is lesser than that of the filter media, thereby forming a gap between the first end of the tubular frame and the top end of the filter media. An annular reinforcing member is disposed in the first endcap and a closure is embedded in the second endcap and attached to the second end of the tubular frame to support the tubular frame.
BRIEF DESCRIPTION OF DRAWINGS
[0009] The features of the present invention, which are believed to be novel, are set forth with
particularity in the appended claims. Embodiments of the present invention will herein after be described in conjunction with the appended drawings provided to illustrate and not to limit the scope of the claims, wherein like designations denote like elements, and in which: [0010] Fig. 1 is a front sectional view of a filter element with a tubular frame, in accordance with an embodiment of the present invention;
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[0011] Fig. 2A is a perspective view of the tubular frame, in accordance with an embodiment of the present invention; [0012] Fig. 2B is a perspective view of the tubular frame snap fitted to a closure, in accordance with an embodiment of the present invention.
[0013] Fig. 3 is a perspective view of a reinforcing member, in accordance with an embodiment of the present invention;
[0014] Fig. 4 is a sectional view of the reinforcing member disposed in the filter element, in
accordance with an embodiment of the present invention.
[0015] Fig. 5 is a sectional view of the closure disposed in the filter element, in accordance with an embodiment of the present invention; and
[0016] Fig. 6 is a perspective view of a mould of the closure and the reinforcing member, in
accordance with an embodiment of the present invention;
DETAILED DESCRIPTION OF EMBODIMENTS
[0017] As used in the specification and claims, the singular forms “a”, “an” and “the” include plural references unless the context clearly dictates otherwise. For example, the term “an
article” may include a plurality of articles unless the context clearly dictates otherwise.
[0018] Those with ordinary skill in the art will appreciate that the elements in the figures are illustrated for simplicity and clarity and are not necessarily drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated, relative to other elements, in order to improve the understanding of the present invention.
[0019] There may be additional components described in the foregoing application that are not depicted on one of the described drawings. In the event such a component is described, but not depicted in a drawing, the absence of such a drawing should not be considered as an omission
of such design from the specification.
[0020] Before describing the present invention in detail, it should be observed that the present invention constitutes a filter element. Accordingly, the components have been represented,
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showing only specific details that are pertinent for an understanding of the present invention so as not to obscure the disclosure with details that will be readily apparent to those with
ordinary skill in the art having the benefit of the description herein.
[0021] As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously
employ the present invention in virtually any appropriately detailed structure. Further, the terms and phrases used herein are not intended to be limiting but rather to provide an
understandable description of the invention.
[0022] Figs. 1-6 illustrate a filter element 100 according to present invention. The filter element 100 may be any of various types of filter elements, including, but not limited to, an air filter, a fuel filter, an oil filter, or a hydraulic filter. As shown in Figs. 1, 2A, 2B, and 3, the filter element 100 includes a filter media 102, a tubular frame 104, a closure 106, a first endcap 108,
a second endcap 110, and a reinforcing member 112. The filter media 102 and the tubular frame 104 may extend along a central axis of the filter element 100. The first endcap 108 and the second endcap 110 may be spaced from one another along the central axis. The filter media
102 is disposed axially between the first and second endcaps 108 and 110. The first endcap 108
is an open endcap with an aperture formed at its center. The second endcap 110 is a closed endcap without any openings.
[0023] The filter media 102 is tubular in shape. The filter media 102 has a hollow inner surface. The filter media 102 is disposed between the first and second endcaps 108 and 110 and extend
around the tubular frame 104. The filter media 102 has a top end 114 and a bottom end 116. In
an embodiment, the filter media 102 may be a pleated filter media 102. The filter media 102
may include cellulose material, spun polyester, or any other material suitable for filtering purposes. [0024] The tubular frame 104 is disposed in the hollow inner surface of the filter media 102.
The filter media 102 is supported radially on inside on the tubular frame 104. The tubular frame 104 includes a wall 118 extending around the central axis and defining an open channel along
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the central axis. As shown in Fig. 2A, the wall 118 of the tubular frame 104 may be of circular cross-section around the central axis. The tubular frame 104 includes openings in wall 118.
The wall 118 with the openings is referred as perforated outer wall. The tubular frame 104
allows fluid to flow radially (relative to central axis) through the wall 118 of the tubular frame
104. The tubular frame 104 has a first end 120 and a second end 122. The first and second ends 120 and 122 include openings that allow fluid to flow along the central axis into or out of the open channel inside the tubular frame 104. The closure 106 is a circular frame that is attached
to the second end 122 of the tubular frame 104. The closure 106 is attached to the tubular frame 104 by snap-on connection as shown in Fig.2B. The closure 106 has supports 124, which are axially protruding, moulded around the circumference. To connect the closure 106 with the tubular frame 104, the closure 106 having the supports 124 is placed on the second end 122 of the tubular frame 104 so it is axially fixed. The second end 122 of the tubular frame 104 is designed to allow the closure 106 to snap-fit on to the tubular frame 104.
[0025] The first end 120 of the tubular frame 104 is in fluid communication with the first endcap 108. This allows fluid to flow between the open channel inside the tubular frame 104
and the aperture in the first endcap 108. The tubular frame 104 may be made of various materials, such as plastic or polymer. The tubular frame 104 with the closure 106 is fixedly
secured to the second endcap 110. The length of the tubular frame 104 is smaller than the length
of the filter media 102, which results in a gap being provided between the first end 120 of the tubular frame 104 and the top end 114 of the filter media 102.
[0026] As shown in Figs. 3 and 4, the reinforcing member 112 is disposed between the top end
114 of the filter media 102 and the first endcap 108. The reinforcing member 112, as shown in Fig. 3, may be of annular shape and provide support to the first endcap 108. The reinforcing member 112 has an opening for fluid to flow through. In an embodiment, the reinforcing member 112 may be glued to the top end 114 of filter media 102 and the first endcap 108.
[0027] The filter media 102 is secured to the first and second endcaps 108 and 110 by
embedding the top and bottom ends 114 and 116 of the filter media 102 in the first and second
endcaps 108 and 110, respectively. The first endcap 108 and the second endcap 110 are made of polyurethane material. The first and second endcaps 108-110 are prepared using a first mould and a second mould, respectively. The first and second moulds with polyurethane material are heated for forming pools of melted polyurethane. Using the first mould, the first
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endcap 108 having less thickness is prepared. For the first endcap 108, the top end 114 of the filter media 102 and the reinforcing member 112 are dipped in molten polyurethane foam of the first mould. The filter media 102 and the reinforcing member 112 are held there until the foam solidifies. This allows the top end 114 of the filter media 102 and the reinforcing member
112 to be embedded in the first endcap 108, as shown in Fig. 4. The reinforcing member 112
allows the first endcap 108 to have less thickness. Although the first endcap 108 is of less thickness, the first endcap 108 can still support the filter media 102 under pressure with the reinforcing member 112. The reinforcing member 112 supports the first endcap 108. For the second endcap 110, the bottom end 116 of the filter media 102 and the closure 106 integrated to the tubular frame 104 are dipped in molten polyurethane foam of the second mould. The filter media 102 and the closure 106 are held there until the foam solidifies. This allows the bottom end 116 of the filter media 102 and the closure 106 to be embedded in the second endcap 110, as shown in Fig. 5. As the closure 106 is embedded in the second endcap 110, it provides axial stability to the tubular frame 104.
[0028] In an embodiment, as shown in Fig 6, the closure 106 and the reinforcing member 112
are formed in a single mould, thereby reducing the required cost of manufacturing. Moreover, as the first end 120 of the tubular frame 104 is not embedded in the first endcap 108, the first endcap 108 that is moulded is of less thickness i.e., thin endcap. This allows the first mould that is used for the preparation of the first endcap 108 to use less amount of polyurethane material, thereby reducing the costs of manufacturing of the first endcap 108. Moreover, the closure 106 provides better radial stability to the tubular frame 104 compared to existing central tube structures of the filter element 100. The reinforcing member 112 prevents the filter media 102 to collapse under pressure due its rigid stability. [0029] The present invention has been described herein with reference to a particular embodiment for a particular application. Although selected embodiments have been illustrated and described in detail, it may be understood that various substitutions and alterations are possible. Those having ordinary skill in the art and access to the present teachings may
recognize additional various substitutions and alterations are also possible without departing from the spirit and scope of the present invention. ,CLAIMS:We Claim:
1. A filter element, comprising:
a tubular filter media having a top end and a bottom end;
a tubular frame, having a perforated outer wall, a first end, and a second end, disposed
in the tubular filter media, wherein the tubular frame adjoining an inner surface of the tubular filter media supports the tubular filter media, and wherein the tubular frame axially extends from the bottom end of the tubular filter media for a distance less than
length of the tube filter media, forming a space between the first end of the tubular frame and the top end of the tubular filter media;
a first endcap and a second end cap secured to the top end and the bottom end of the tubular filter media, respectively;
a closure attached to the second end of the tubular frame, wherein the closure is embedded in the second endcap to support the tubular frame; and
an annular reinforcing member disposed between the top end of the tubular filter media and the first endcap to support the tubular filter media. 2. The filter element of claim 1, wherein the first endcap is an open endcap with an
aperture therethrough and the second endcap is a closed endcap.
3. The filter element of claim 1, wherein the first and second endcaps are formed from polyurethane material.
4. The filter element of claim 1, wherein the top and bottom ends of the tubular filter media are integrally embedded in the first and second endcaps, respectively.
5. The filter element of claim 1, wherein the closure is attached by snap-on connection to
the tubular frame.