Backflush filter assembly

Abstract

A filter assembly (10) includes an inner filter basket (20) including an elongated tubular portion having a first open end and a first closed end. The tubular portion defines a plurality of perforations therethrough. An outer surface of the tubular portion is seamless. An annular first rim (44) extends outwardly from the open end of the tubular portion. The filter assembly (10) further includes an outer filter basket (22) having a second open end, the inner filter basket (20) being housed in the outer filter basket (22). An annular second rim (46) extends outwardly from the second open end of the outer filter basket (22). The first and second rims (44, 46) are configured to retain a fabric filter bag (18) between the inner filter basket (20) and the outer filter basket (22).

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to U.S. non-provisional application No. 17 / 567520, filed January 3, 2022, and U.S. provisional application No. 63 / 142622, filed January 28, 2021, the entire disclosure of each of which is incorporated herein by reference. Technical Field

[0003] The present invention generally relates to a backwash filter assembly configured to remove particulates and other contaminants from a fluid, and particularly to a backwash filter assembly having replaceable bag filter elements. Summary of the Invention

[0004] According to one or more aspects of this disclosure, a filter assembly includes an inner filter basket comprising an elongated tubular portion having a first open end and a first closed end, the tubular portion defining a plurality of perforations therethrough. The outer surface of the tubular portion is seamless. An annular first edge extends outwardly from the open end of the tubular portion. The filter assembly also includes an outer filter basket having a second open end, within which the inner filter basket is received. An annular second edge extends outwardly from the second open end of the outer filter basket. The first and second edges are configured to hold a bag filter between the inner and outer filter baskets.

[0005] In one or more embodiments of the filter assembly according to the preceding paragraph, the tubular portion of the inner filter basket has a non-porous strip extending from the open end to the closed end.

[0006] In one or more embodiments of the filter assembly according to any of the preceding paragraphs, the filter assembly further includes a fabric filter bag and a flange defining an elastic annular ring surrounding an opening in the fabric filter bag.

[0007] In one or more embodiments of the filter assembly according to any of the preceding paragraphs, the flange and the annular ring are integrally formed from the same elastic material.

[0008] In one or more embodiments of the filter assembly according to any of the preceding paragraphs, the flange has a cylindrical portion to which a fabric filter bag is attached.

[0009] In one or more embodiments of the filter assembly according to any of the preceding paragraphs, the flange has a truncated conical cross section between the cylindrical portion and the annular ring.

[0010] In one or more embodiments of the filter assembly according to any of the preceding paragraphs, the outer edge of the flange has a generally circular cross-section, and the diameter of the outer edge is greater than the thickness of the annular ring.

[0011] According to one or more aspects of this disclosure, a filter assembly includes a fabric filter bag and a flange defining an elastomeric annular ring surrounding an opening in the fabric filter bag. The filter assembly may also include any feature of any of the foregoing sections.

[0012] In one or more embodiments of the filter assembly according to the preceding paragraph, the flange and the annular ring are integrally formed from the same elastic material.

[0013] In one or more embodiments of the filter assembly according to any of the preceding paragraphs, the flange has a cylindrical portion to which a fabric filter bag is attached.

[0014] In one or more embodiments of the filter assembly according to any of the preceding paragraphs, the flange has a truncated conical cross section between the cylindrical portion and the annular ring.

[0015] In one or more embodiments of the filter assembly according to any of the preceding paragraphs, the outer edge of the flange has a generally circular cross-section and wherein the diameter of the outer edge is greater than the thickness of the annular ring.

[0016] According to one or more aspects of this disclosure, a filter assembly includes a pressure vessel having a cover movable from a sealed closed position to an open position allowing access to the interior of the pressure vessel, a plurality of filter elements arranged within the pressure vessel, and a pneumatic manifold integrated in the cover and movable with the cover. When the cover is in the closed position, a pneumatic tube of the pneumatic manifold is positioned above the open end of each of the plurality of filter elements. The filter assembly may also include any features of any of the foregoing sections.

[0017] In one or more embodiments of the filter assembly according to the preceding paragraph, the pneumatic manifold is configured to forcibly evacuate fluid from the pressure vessel by delivering compressed gas to each of the plurality of filter elements. Attached Figure Description

[0018] The invention will now be described by way of example with reference to the accompanying drawings, in which:

[0019] Figure 1A and Figure 1B These are top and side views of a filter assembly according to some embodiments;

[0020] Figure 2A and Figure 2B It is according to some embodiments having an alternative opening mechanism Figure 1A and Figure 1B Top and side views of the filter component;

[0021] Figure 3A and Figure 3B These are top and side views of another filter component according to some embodiments;

[0022] Figure 4 This is a perspective view of a filter element according to some embodiments;

[0023] Figures 5A-5C According to some embodiments Figure 4 Side view, end view and perspective view of the inner filter basket of the filter element;

[0024] Figure 6 According to some embodiments Figure 4 A close-up view of the inner filter basket;

[0025] Figure 7 According to some embodiments Figure 4 A diagram of the outer filter basket of the filter element;

[0026] Figure 8A and Figure 8B According to some embodiments Figure 4 A perspective view of the fabric filter bag containing the filter element;

[0027] Figures 9A-9C According to some embodiments Figure 8A and Figure 8B Front, side and rear views of the filter bag flange of the fabric filter bag;

[0028] Figure 10 According to some embodiments Figures 9A-9C A perspective rear view of the filter bag flange;

[0029] Figure 11 According to some embodiments Figures 9A-9C Front view of the filter bag flange; and

[0030] Figure 12 According to some embodiments Figures 9A-9C Another perspective rear view of the filter bag flange. Detailed Implementation

[0031] This article provides and Figures 1A-3B A backwash filter assembly 10 is shown. The filtration system has a pressure vessel 12 with a cover 14, which is movable to allow access. Figure 4 One or more replaceable filter elements 16 shown have fabric filter bags 18 held within an inner filter basket 20 and an outer filter basket 22. Figure 1A and Figure 1B A filter assembly 10 with a spring-loaded auxiliary cover 14 is shown, while Figure 2A and Figure 2BA filter assembly 10 with a counterweight auxiliary cover is shown. Other embodiments of the filter assembly may have a single filter element, two filter elements, or more than four filter elements. Yet another embodiment of the filter assembly may also have multiple pressure vessels, each pressure vessel having one or more filter elements.

[0032] These filter elements 16 are configured to remove particles or other contaminants from pressurized fluid supplied to the filter assembly via fluid inlet 24 and discharged from the filter assembly via fluid outlet. The filter assembly also includes a pneumatic inlet 28 and a discharge outlet 30. The pneumatic inlet 28 and discharge outlet 30 are arranged opposite to the fluid inlet 24 and fluid outlet 26. To backwash the filter assembly, valves (not shown) controlling fluid inlet 24 and fluid outlet 26 are closed, and valves controlling pneumatic inlet 28 and discharge outlet 30 are opened. Pneumatic inlet 28 provides a flow of compressed gas, such as compressed air, flowing in the opposite direction to the normal fluid flow through the filter element 16. This compressed air flow removes particles from the surface of the filter element 16 and forces the particles, along with any remaining fluid in the filter assembly 10, through discharge outlet 30. The pneumatic inlet 28 and discharge outlet 30 valves are then closed, and the fluid inlet 24 and fluid outlet 26 valves are opened to restore normal filtration operation.

[0033] like Figure 1A and Figure 1B As best shown, the movable cover 14 of the filter assembly 10 includes a pneumatic manifold 32 that, when the cover 14 is closed, is positioned above or within the open end of each filter element 16. These pneumatic manifolds are configured to deliver an airflow of compressed air to each filter element 16 to backwash the fabric filter bag 18. The integration of the manifold 32 into the movable cover 14 significantly simplifies the procedure for maintaining and replacing the fabric filter bags 18 in the filter elements 16, because the pneumatic manifold swings away from the filter element when the cover is open, and access to the fabric filter bag is possible without disassembling the pneumatic manifold.

[0034] In an alternative embodiment, the filter assembly may be configured for fluid backwashing of the filter element instead of the pneumatic backwashing described above.

[0035] Figure 5 and Figure 6The inner filter basket 20 shown is made of a perforated sheet of metal (e.g., stainless steel). The sheet is rolled into a tube and the edges 36 are welded together, and then the weld is machined to remove any raised seams on the outer surface of the inner basket. This provides an easier placement of the inner filter basket 20 into the fabric filter bag 18 because it eliminates potential sources of obstruction formed by raised welds, curls, or overlapping seams, which make it more difficult to insert the inner filter basket 20 into the fabric filter bag 18 and could potentially damage the fabric filter bag 18. The sidewalls 34 of the inner filter basket are at least 3 mm (0.125 inches) thick and do not require an inner reinforcing ring as in previous inner filter basket designs. The shape of the inner filter basket 20 is preferably typically cylindrical, but alternatively it can have a truncated conical shape.

[0036] Figure 7 The outer filter basket 22 shown has a wire loop 40, which is held by a flat metal strip 42 on the outside of the wire loop instead of a circular metal ring.

[0037] Figure 8A and Figure 8B The fabric filter bag 18 shown has Figures 9A-12 The collar or flange 38 shown is located at the open end of the fabric filter bag 18 and is made of elastic rubber (e.g., EPDM or FKM material). Other elastomers or polymeric materials may also be used, depending primarily on the material requirements of the fluid being filtered. Figure 3A and Figure 3B As shown, flange 38 is sandwiched between the metal top edges 44 and 46 of the inner and outer filter baskets. Flange 38 has an O-ring 48 integrally formed on its outer edge, configured to seal the metal top edge 44 of the inner filter basket 20 to the metal top edge 46 of the outer filter basket 22. O-ring 48 at least partially seals flange 38 to both the inner basket edge 44 and the outer basket edge 46 to help reduce fluid bypassing the filter element 16 during filter operation. O-ring 48 may be integrally formed with flange 38 and made of the same elastic material. Alternatively, O-ring 48 may be formed of a different elastic material than flange 38, having a different hardness value than the flange material using a secondary molding process. The open end of fabric filter bag 18 is attached, for example, by sewing to the neck of flange 38 to a cylindrical neck 50 extending from flange 38.

[0038] The cover 14 may also include a plurality of clamping features 52 integrated with and extending therefrom the inner surface of the cover 14, which contact the metal top edge 44 of the inner filter basket 20 when the cover 14 is closed. These clamping features 52 hold the filter elements 16 in place during operation of the filter assembly 10. Each clamping feature 52 includes a rod 54 having a fixed end attached to the cover 14 and a free end defining a foot 56 that contacts the metal top edge 44 of the inner filter basket 20. The rod 54 may have a cylindrical shape, while the foot 56 may have a disc shape with a diameter greater than that of the rod 54. Each filter assembly 10 may be held in place by two or more clamping features 52. The clamping features 52 may be arranged such that one clamping feature 52 can contact the metal top edge 44 of more than one filter assembly 10. These clamping features 52 provide the advantage that it eliminates the need to loosen and / or remove threaded fasteners that can be used to individually secure the filter assembly, as implemented in existing filter designs for removing or replacing the filter assembly.

[0039] While the invention has been described according to its preferred embodiments, it is not intended to be so limited, but rather to be limited only to the scope set forth in the appended claims. For example, the above embodiments (and / or aspects thereof) can be used in combination with each other. Furthermore, many modifications can be made to configure specific situations or materials according to the teachings of the invention without departing from the scope of the invention. The dimensions, material types, orientations, and quantities and positions of the various components described herein are intended to define parameters of certain embodiments and are by no means limiting and are merely prototypical embodiments.

[0040] After reading the above description, many other embodiments and modifications within the spirit and scope of the claims will be apparent to those skilled in the art. Therefore, the scope of the invention should be determined by referring to the following claims and the full scope of their equivalents.

[0041] As used herein, “one or more” includes functions performed by one element, functions performed by more than one element, such as in a distributed manner, multiple functions performed by one element, multiple functions performed by several elements, or any combination of the above.

[0042] It will also be understood that although the terms first, second, etc., are used in certain circumstances herein to describe various elements, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, without departing from the scope of the various embodiments described, a first contact may be referred to as a second contact, and similarly, a second contact may be referred to as a first contact. Both first and second contacts are contacts, but not the same contact.

[0043] The terminology used in the description of the various embodiments described herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description of the various described embodiments and the appended claims, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and covers all possible combinations of one or more of the associated listed items. It will be further understood that, when used in this specification, the terms “comprising,” “including,” “containing,” and / or “comprising” designate the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0044] As used herein, depending on the context, the term "if" may optionally be interpreted as meaning "when" or "based on" or "in response to determination" or "in response to detection." Similarly, the phrase "if determination" or "if [the condition or event] is detected" may optionally be interpreted as "when determination" or "in response to determination" or "when [the condition or event] is detected" or "in response to detection of [the condition or event]," depending on the context.

[0045] Furthermore, while terms of sequence or orientation may be used, the elements therein should not be limited by these terms. Unless otherwise stated, all terms of sequence or orientation are used to distinguish one element from another and do not indicate any particular order, sequence of operations, direction, or orientation, unless otherwise stated.

Claims

1. A filter assembly (10), comprising: The pressure vessel (12) has a cover (14) that can be moved from a closed position where the pressure vessel (12) is sealed to an open position that allows access to the interior of the pressure vessel (12). Multiple filter elements (16) are arranged within the pressure vessel (12); and A pneumatic manifold (32), integrated into the cover (14) and movable with the cover (14), wherein when the cover (14) is in the closed position, one of the pneumatic tubes in the pneumatic manifold (32) is positioned above the open end of each of the plurality of filter elements (16), wherein each filter element includes: An inner filter basket (20) includes an elongated tubular portion having a first open end and a first closed end, the tubular portion defining a plurality of through-holes therethrough, wherein the outer surface of the tubular portion is seamless, and wherein an annular first edge (44) extends outwardly from the first open end of the tubular portion; and An outer filter basket (22) having a second open end, the inner filter basket (20) being housed within the outer filter basket, wherein an annular second edge (46) extends outwardly from the second open end of the outer filter basket (22); and Fabric filter bag (18) is arranged between the inner filter basket (20) and the outer filter basket (22).

2. The filter assembly (10) according to claim 1, wherein the pneumatic manifold (32) is configured to forcibly evacuate fluid from the pressure vessel by delivering compressed gas to each of the plurality of filter elements (16).

3. The filter assembly (10) of claim 1, wherein the filter assembly (10) includes a spring attached to the pressure vessel (12) and the cap (14) and configured to reduce the force required to lift the cap (14) from the closed position.

4. The filter assembly (10) according to claim 3, wherein the spring is a tension spring.

5. The filter assembly (10) of claim 1, wherein the cover (14) further comprises a counterweight configured to reduce the force required to lift the cover (14) from the closed position.

6. The filter assembly (10) according to claim 5, wherein the counterweight extends cantilevered from the cover (14).

7. The filter assembly (10) according to claim 1 further includes a plurality of clamping features (52) extending from the cover (14), the clamping features being configured to secure the plurality of filter elements (16) within the pressure vessel (12).

8. The filter assembly (10) according to claim 7, wherein each of the plurality of clamping features (52) contacts at least two of the plurality of filter elements (16).

9. The filter assembly (10) of claim 1, wherein the fabric filter bag (18) has an open end and a closed end; and wherein a flange (38) defines an elastic annular ring (48) attached to the open end of the fabric filter bag (18).

10. The filter assembly (10) of claim 9, wherein the flange (38) is disposed between the first edge (44) and the second edge (46).

11. The filter assembly (10) according to claim 9, wherein the flange (38) and the resilient annular ring (48) are integrally formed of the same resilient material.

12. The filter assembly (10) of claim 9, wherein the flange (38) has a cylindrical portion (50) to which the fabric filter bag (18) is attached.

13. The filter assembly (10) according to claim 12, wherein the flange (38) has a truncated conical cross section between the cylindrical portion (50) and the resilient annular ring (48).

14. The filter assembly (10) of claim 9, wherein the outer edge of the flange (38) has a generally circular cross-section, and wherein the diameter of the outer edge is greater than the thickness of the resilient annular ring (48).

Images