Patent Description:
Pulse cleaning of air filter systems may be used to improve filtering capacity and filter media life. Typically, air filter systems must be designed and built to include the components needed to provide pulse cleaning. <CIT> shows a filtration assembly including a housing with a filter unit between a raw fluid inlet port and a filtered fluid outlet port and a pulse jet device for directing a pulse of compressed gas into the interior of the filter unit. A further filtration assembly is disclosed in <CIT>, which includes a housing with filter units between a raw fluid inlet port and a filtered fluid outlet port. A filter rinsing assembly is in communication with a rinsing fluid inlet port, and a propulsion fluid inlet port is in communication with a propulsion mechanism.

A method for retrofitting a pulse ring assembly is disclosed in claims <NUM>-<NUM>, while a pulse ring retrofit apparatus is disclosed in claims <NUM>-<NUM>.

Pulse ring assemblies for air cleaner systems used in vehicles and related methods are described herein. In one or more embodiments, the pulse ring assembly may be configured to be positioned or retrofitted between an air filter outlet and an engine intake. In other embodiments, the pulse ring assembly may be incorporated into an air cleaner body. The pulse ring assembly may include a pulse jet apparatus that is configured to direct gas or fluid towards the air filter outlet (e.g., an outlet through which filtered air passes towards the engine intake) to force dust and debris off of filter media (e.g., positioned proximate the air filter outlet). The pulse ring assembly may be described as a self-contained unit that may be attached or retrofit to the air filter outlet on one end and may be attached or retrofit to the engine intake on the other end. In other words, the air filter outlet or engine intake may not need to be modified (e.g., by creating openings or inserting components through a sidewall thereof) to include the pulse jet apparatus. As such, for example, the pulse ring assembly may be retrofit onto an existing air filter system passageway to convert the passageway into a self-cleaning passageway (e.g., because the pulse ring assembly includes components to clean the filter media). Also, for example, the pulse ring assembly may be incorporated into an air cleaner body (e.g., at the end of the air cleaner) and may be positioned to generate pulses that force air through a safety filter element and/or between the safety filter element and a primary filter element.

An exemplary air cleaner system may include an outer tube, an inner tube, and a pulse jet apparatus. The outer tube may extend between an outer filter outlet end and an outer engine intake end. The outer tube may include an interior surface and an exterior surface. The interior surface of the outer tube may define an outer tube passageway through the outer tube between the outer filter outlet end and the outer engine intake end. The outer tube may include a pulse port extending between the interior and exterior surfaces into the outer tube passageway. The inner tube may extend along a longitudinal axis between an inner filter outlet end and an inner engine intake end. The inner tube may include an interior surface and an exterior surface. The interior surface of the inner tube may define an inner tube passageway through the inner tube between the inner filter outlet end and the inner engine intake end. The outer tube may be configured to receive the inner filter outlet end within the outer tube passageway such that at least a portion of the interior surface of the outer tube faces at least a portion of the exterior surface of the inner tube proximate the inner filter outlet end. Filtered air may be configured to flow from a first filter cartridge proximate the outer filter outlet end to an engine proximate the inner engine intake end. The pulse jet apparatus may be in fluid communication with the pulse port of the outer tube. The pulse jet apparatus may be configured to direct gas through the pulse port towards the first filter cartridge (e.g., towards the outer filter outlet end).

In one or more embodiments of the air cleaner system as described herein, the air cleaner system further comprises a housing extending around the exterior surface of the outer tube, wherein the housing comprises a first filter cartridge in fluid communication with the inner tube passageway and a second filter cartridge surrounding the first filter cartridge, wherein the housing defines an additional pulse port positioned between the first and second filter cartridges and an inlet such that the first and second filter cartridges are positioned between the inlet and the inner tube passageway, wherein filtered air is configured to flow from the inlet to the engine proximate the inner engine intake end, wherein the pulse jet apparatus is in fluid communication with the additional pulse port, wherein the pulse jet apparatus is configured to direct gas through the additional pulse port.

In one or more embodiments of the air cleaner system as described herein, the additional pulse port defines an annular shape between the first and second filter cartridges.

In one or more embodiments of the air cleaner system as described herein, the pulse jet apparatus is configured to be selectively activated such that the gas is directed in discrete pulses through the additional pulse port.

In one or more embodiments of the air cleaner system as described herein, the pulse jet apparatus is configured to be selectively activated such that such that the gas is directed in discrete pulses from the pulse port of the outer tube towards the outer filter outlet end.

In one or more embodiments of the air cleaner system as described herein, the pulse port is positioned along the outer tube at a location between the inner filter outlet end and the outer engine intake end.

In one or more embodiments of the air cleaner system as described herein, the pulse port is positioned closer to the outer engine intake end than the inner filter outlet end.

In one or more embodiments of the air cleaner system as described herein, the pulse port is spaced a distance from the inner filter outlet end of about <NUM> or less measured along the longitudinal axis.

In one or more embodiments of the air cleaner system as described herein, the air cleaner system further comprises a seal between the interior surface of the outer tube and the exterior surface of the inner tube.

In one or more embodiments of the air cleaner system as described herein, the interior surface of the outer tube is concentric with and spaced a selected gap distance from the exterior surface of the inner tube.

In one or more embodiments of the air cleaner system as described herein, the gap distance is about <NUM> or more and/or <NUM> or less.

In one or more embodiments of the air cleaner system as described herein, the interior surface of the outer tube defines a first diameter proximate the outer filter outlet end and a second diameter proximate the outer engine intake end, wherein the first and second diameters are different.

In one or more embodiments of the air cleaner system as described herein, the first diameter proximate the outer filter outlet end is less than or equal to the second diameter proximate the outer engine intake end.

In one or more embodiments of the air cleaner system as described herein, the first diameter of the interior surface of the outer tube is equal to or less than a diameter of the exterior surface of the inner tube.

In one or more embodiments of the air cleaner system as described herein, the air cleaner system further comprises a controller operably connected to the pulse jet apparatus, wherein the controller is configured to selectively activate the pulse jet apparatus.

In one or more embodiments of the air cleaner system as described herein, the controller is configured to automatically activate the pulse jet apparatus in response to a predetermined pressure differential across the first filter cartridge.

An exemplary method of retrofitting a pulse ring assembly between an air filter outlet of an air cleaner system and an engine intake. The method may include connecting an outer tube to the air filter outlet. The outer tube may extend between an outer filter outlet end connected to the air filter outlet and an outer engine intake end. The outer tube may include an interior surface and an exterior surface. The interior surface of the outer tube may define an outer tube passageway through the outer tube between the outer filter outlet end and the outer engine intake end. The outer tube may include a pulse port extending between the interior and exterior surfaces into the outer tube passageway.

The method may also include positioning an inner tube within the outer tube passageway. The inner tube may extend along a longitudinal axis between an inner filter outlet end and an inner engine intake end. The inner tube may include an interior surface and an exterior surface. The interior surface of the inner tube may define an inner tube passageway through the inner tube between the inner filter outlet end and the inner engine intake end. The inner filter outlet end may be positioned within the outer tube passageway such that an outer pulse portion of the interior surface of the outer tube faces the exterior surface of the inner tube. Filtered air may be configured to flow from the air filter outlet to the engine intake. The method may further include connecting the inner engine intake end to the engine intake and connecting a pulse jet apparatus in fluid communication with the pulse port of the outer tube. The pulse jet apparatus may be configured to direct gas from the pulse port of the outer tube towards the outer filter outlet end.

In one or more embodiments of the method as described herein, the method further comprises selectively activating the pulse jet apparatus.

In one or more embodiments of the method as described herein, selectively activating the pulse jet apparatus comprises directing gas in spaced-apart pulses from the pulse port of the outer tube towards the outer filter outlet end.

In one or more embodiments of the method as described herein, the method further comprises manually operating the pulse jet apparatus to direct gas from the pulse port of the outer tube towards the outer filter outlet end.

In one or more embodiments of the method as described herein, the method further comprises operating the pulse jet apparatus to direct gas from the pulse port of the outer tube towards the outer filter outlet end when a predetermined pressure differential across a filter cartridge proximate the air filter outlet is reached.

In one or more embodiments of the method as described herein, the pulse port is positioned closer to the outer engine intake end than the inner filter outlet end.

In one or more embodiments of the method as described herein, the method further comprises providing a seal between the interior surface of the outer tube and the exterior surface of the inner tube.

In one or more embodiments of the method as described herein, the pulse port is positioned closer to the seal than the inner filter outlet end.

In one or more embodiments of the method as described herein, the interior surface of the outer tube is concentric with and spaced a selected gap distance from the exterior surface of the inner tube.

In one or more embodiments of the method as described herein, the gap distance is about <NUM> or more and/or <NUM> or less.

In one or more embodiments of the method as described herein, the pulse port is spaced a distance from the inner filter outlet end of about <NUM> or less measured along the longitudinal axis.

In one or more embodiments of the method as described herein, the interior surface of the outer tube defines a first diameter proximate the outer filter outlet end and a second diameter proximate the outer engine intake end, wherein the first and second diameters are different.

In one or more embodiments of the method as described herein, the first diameter proximate the outer filter outlet end is less than or equal to the second diameter proximate the outer engine intake end.

In one or more embodiments of the method as described herein, the first diameter of the interior surface of the outer tube is equal to or less than a diameter of the interior surface of the inner tube.

An exemplary pulse ring retrofit apparatus for an air cleaner system connected between an air filter outlet and an engine intake, the retrofit apparatus may include an outer tube, an inner tube, and a pulse jet apparatus. The outer tube may extend between an outer filter outlet end and an outer engine intake end. The outer filter outlet end may be connected to the air filter outlet. The outer tube may include an interior surface and an exterior surface. The interior surface of the outer tube may define an outer tube passageway through the outer tube between the outer filter outlet end and the outer engine intake end. The outer tube may include a pulse port extending between the interior and exterior surfaces into the outer tube passageway. The inner tube may extend along a longitudinal axis between an inner filter outlet end and an inner engine intake end. The inner engine intake end may be connected to the engine intake. The inner tube may include an interior surface and an exterior surface. The interior surface of the inner tube may define an inner tube passageway through the inner tube between the inner filter outlet end and the inner engine intake end. The outer engine intake end may be configured to receive the inner filter outlet end within the outer tube passageway such that an outer pulse portion of the interior surface of the outer tube faces the exterior surface of the inner tube. Filtered air may be configured to flow from a filter cartridge proximate the air filter outlet to an engine proximate the engine intake. The pulse jet apparatus may be in fluid communication with the pulse port of the outer tube. The pulse jet apparatus may be configured to direct gas from the pulse port of the outer tube towards the outer filter outlet end.

In one or more embodiments of the pulse ring retrofit apparatus as described herein, the pulse jet apparatus is configured to be selectively activated such that the gas is directed in spaced-apart pulses from the pulse port of the outer tube towards the outer filter outlet end.

In one or more embodiments of the pulse ring retrofit apparatus as described herein, the pulse port is positioned in the outer tube at a location between the inner filter outlet end and the outer engine intake end.

In one or more embodiments of the pulse ring retrofit apparatus as described herein, the pulse port is positioned closer to the outer engine intake end than the inner filter outlet end.

In one or more embodiments of the pulse ring retrofit apparatus as described herein, the pulse port is spaced a distance from the inner filter outlet end by about <NUM> or less measured along the longitudinal axis.

In one or more embodiments of the pulse ring retrofit apparatus as described herein, the pulse ring retrofit apparatus further comprises a seal between the interior surface of the outer tube and the exterior surface of the inner tube.

The disclosure may be more completely understood in consideration of the following detailed description of various embodiments of the disclosure in connection with the accompanying drawings.

In the following description of illustrative embodiments, reference is made to the accompanying figures of the drawing, which form a part hereof, and in which are shown, by way of illustration, specific embodiments. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention.

The disclosure herein includes illustrative embodiments of systems, apparatus, structures, and methods for a pulse ring assembly that may be positioned or retrofit between an air filter outlet and an engine intake of a vehicle (e.g., a tank, an armored truck, etc.). The pulse ring assembly may be configured (e.g., using a pulse jet apparatus) to force pulses of gas or fluid towards the air filter outlet of an air cleaner system to move debris and sediment out of an air cleaner housing of the vehicle. The pulse ring assembly may be retrofit into the filtering system such that a section of the filtering system may be removed between the air filter outlet (e.g., downstream of air filter media/cartridge) and the engine intake so that the pulse ring assembly may be positioned therebetween. As such, the filtering system may be converted from a standard filtering system into one that includes a self-cleaning apparatus (e.g., the pulse ring assembly described herein) that may clean the air filter media using one or more pulses of gas or fluid. In other embodiments, the pulse ring assembly may be incorporated into an air cleaner housing.

The pulse ring assembly may take any suitable form extending between the air filter outlet and the engine intake. For example, the pulse ring assembly may include an outer tube and an inner tube that overlap (e.g., one extends within the other), with the ends of the outer and inner tubes that are not overlapping configured to be connected to either the air filter outlet or the engine intake. The overlapping portions may form a concentric or annular chamber (e.g., between an inner surface of the outer tube and an outer surface of the inner tube) that may be in fluid communication with the pulse jet apparatus. The pulse jet apparatus may generate a pulse of gas or fluid (e.g., to clean the air filter media) that fills the concentric or annular chamber and may be forced towards the air filter outlet (e.g., due to the structure of the pulse ring assembly, due to the pressure differential, etc.). This pulse of gas may be described as a pulse ring due to the shape created by the configuration of the inner and outer tubes (e.g., defining concentric or annular opening/chamber).

One illustrative embodiment of an air cleaner system within a vehicle <NUM> is depicted in <FIG>. Specifically, <FIG> illustrates an M1 tank, however, the air cleaner system described herein may be applied to air filter systems of a variety of vehicles and/or equipment. For example, the air cleaner system may be implemented within tracked personnel carriers, wheeled vehicles, mobile generators, stationary generators, etc..

The vehicle <NUM> may include an inlet <NUM> configured to allow the flow of air from the exterior environment, through filter media, and towards the engine intake. The inlet <NUM> may be located at any suitable location on the vehicle <NUM>. In some embodiments, the vehicle <NUM> may include a pulse ring assembly <NUM> (not shown in <FIG>), as described herein, between the inlet <NUM> and the engine intake such that the air cleaner system (e.g., air filtering system) may be configured to clean itself from debris or sediment on the exterior of the filter media. In other embodiments, the vehicle may be modified such that a pulse ring assembly <NUM> may be retrofitted into the air cleaner system between the inlet <NUM> and the engine intake.

The pulse ring assembly <NUM>, as described herein, may simplify the process of converting an air filter system present in a vehicle to include a self-cleaning apparatus. For example, the pulse ring assembly <NUM> may be connected to the air filter system of the vehicle <NUM> in-line with the air filter system and only connected at two locations along the air filter system. For example, a section of the air filter system (e.g., a section of tubing) may be removed and replaced with the pulse ring assembly <NUM> described herein. Removing a section of the air filter system and replacing it with a pulse ring assembly <NUM> may allow for more robust and solid connections between the pulse ring assembly <NUM> and the existing portions of the air filter system. For example, connecting the pulse ring assembly <NUM> into the air filter system may only include connecting the ends of two pipes or tubes (e.g., an end of the pulse ring assembly <NUM> with an end of the air filter system).

Further, self-cleaning apparatus typically extend into the flow path of the air filter system and generate a pulse of gas from an end of the self-cleaning apparatus that is centered in the air filter system passageway. As a result, air flow from the air filter outlet to the engine intake may pass directly into the end of the self-cleaning apparatus. Providing a pulse ring assembly <NUM> that produces a pulse ring that is generated along the interior surface of the air filter system passageway (e.g., as described herein) may alleviate this issue. For example, the geometry and configuration of the pulse ring assembly <NUM> may reduce the likelihood of air flow from the air filter outlet to the engine intake passing directly into the end of the self-cleaning apparatus.

The pulse ring assembly <NUM> may be actuated manually or automatically. Further, the pulse ring assembly <NUM> may provide for hands-off solutions to maintaining a clean filter system. For example, the pulse cleaner apparatus may help to further automate the cleaning process to ensure an efficient and effective way to maintain clean filter media.

<FIG> illustrates a schematic representation of a pulse ring assembly <NUM> positioned between an air filter outlet <NUM> and an engine intake <NUM>. The air filter outlet <NUM> may be an extension from the inlet <NUM> of the vehicle <NUM> (e.g., as shown in <FIG>). In other words, air from the external environment may pass from the inlet <NUM> of the vehicle <NUM>, through a filter cartridge or filter media (e.g., to filter the external air before it enters the engine intake <NUM>) towards the air filter outlet <NUM>. The filtered air may then pass through the pulse ring assembly <NUM> and towards the engine intake <NUM>. The engine intake <NUM> may be any suitable path or structure to deliver filtered air to the engine.

The pulse ring assembly <NUM> may be positioned between the air filter outlet <NUM> and the engine intake <NUM> to, e.g., form a passageway between the air filter outlet <NUM> and the engine intake <NUM>. Further, the pulse ring assembly <NUM> may be positioned downstream of the air filter outlet <NUM> (e.g., between the filter cartridge and the engine intake <NUM>, and within a clean air space) such that the pulse ring assembly <NUM> may direct a pulse of gas back towards the air filter outlet <NUM> (e.g., to clean the filter cartridge/media). The pulse ring assembly <NUM> may be initially positioned between the air filter outlet <NUM> and the engine intake <NUM> (e.g., during construction of the air filter system) or may be retrofit (e.g., attached after construction of the air filter system) between the air filter outlet <NUM> and the engine intake <NUM>. The pulse ring assembly <NUM> may be coupled or attached to each of the air filter outlet <NUM> and the engine intake <NUM> in any suitable way, e.g., by welding, mechanical fasteners, clamps, fittings, etc. Further, the interface between the pulse ring assembly <NUM> and each of the air filter outlet <NUM> and the engine intake <NUM> may be sealed to, e.g. prevent undesired elements from entering and potentially contaminating the clean air space.

In such embodiments in which the pulse ring assembly <NUM> may be retrofit between the air filter outlet <NUM> and the engine intake <NUM>, a section of the air filter system may be removed between the air filter outlet <NUM> and the engine intake <NUM> and replaced with the pulse ring assembly <NUM>. As such, instead of attempting to modify the existing air filter system to include components to assist in pulse cleaning the filter cartridge/media (e.g., by producing selective openings to add components or tubes for a pulse jet apparatus), an entire section of the air filter system may be replaced with the pulse ring assembly <NUM> (e.g., which includes the components necessary to provide pulse cleaning). Replacing a section of the air filter system with the pulse ring assembly <NUM> may provide a more efficient and effective modification than creating selective openings at various points along the air filter system. For example, the pulse ring assembly <NUM> may be only attached within the air filter system at the air filter outlet <NUM> and the engine intake <NUM>-not at various locations along the air filter system.

A cross-sectional schematic view of one illustrative embodiment of a pulse ring assembly <NUM> connected between an air filter outlet <NUM> and an engine intake <NUM> is shown in <FIG>. For example, the pulse ring assembly <NUM> may be arranged or oriented such that filtered air may flow from a filter cartridge proximate the air filter outlet <NUM>, through the pulse ring assembly <NUM>, and towards an engine proximate the engine intake <NUM>. Furthermore, the pulse ring assembly <NUM> may be arranged or oriented to extend along a longitudinal axis <NUM>. In some embodiments, the longitudinal axis <NUM> may define a straight axis such that the pulse ring assembly <NUM> extends along a straight line. In other embodiments, the longitudinal axis <NUM> may extend along a path that is not straight (e.g., a curved path).

The pulse ring assembly <NUM> may include an outer tube <NUM> extending between an outer filter outlet end <NUM> and an outer engine intake end <NUM> (e.g., along the longitudinal axis <NUM>). The outer filter outlet end <NUM> may be positioned closer to the air filter outlet <NUM> than the engine intake <NUM> and the outer engine intake end <NUM> may be positioned closer to the engine intake <NUM> than the air filter outlet <NUM>. Further, in one or more embodiments, the outer filter outlet end <NUM> (e.g., the filter outlet end of the outer tube <NUM>) may be coupled or attached to the air filter outlet <NUM> (e.g., as described with reference to <FIG>).

Furthermore, the outer tube <NUM> may include an interior surface <NUM> and an exterior surface <NUM>. The interior surface <NUM> of the outer tube <NUM> may define an outer tube passageway <NUM> through the outer tube <NUM> between the outer filter outlet end <NUM> and the outer engine intake end <NUM>. In other words, gas or fluid may flow through the outer tube <NUM> (e.g., within the outer tube passageway <NUM>) between the outer filter outlet end <NUM> and the outer engine intake end <NUM>. Additionally, in one or more embodiments, the outer tube <NUM> may include a pulse port <NUM> extending between the interior surface <NUM> and the exterior surface <NUM> into the outer tube passageway <NUM> (e.g., defining an opening through the outer tube <NUM>). In other words, the pulse port <NUM> may provide a path of fluid communication between something positioned outside of the exterior surface <NUM> and the outer tube passageway <NUM>.

The pulse ring assembly <NUM> may also include an inner tube <NUM> extending between an inner filter outlet end <NUM> and an inner engine intake end <NUM> (e.g., along the longitudinal axis <NUM>). The inner filter outlet end <NUM> may be positioned closer to the air filter outlet <NUM> than the engine intake <NUM> and the inner engine intake end <NUM> may be positioned closer to the engine intake <NUM> than the air filter outlet <NUM>. Further, in one or more embodiments, the inner engine intake end <NUM> may be coupled or attached to the engine intake <NUM> (e.g., as described with reference to <FIG>).

Furthermore, the inner tube <NUM> may include an interior surface <NUM> and an exterior surface <NUM>. The interior surface <NUM> of the inner tube <NUM> may define an inner tube passageway <NUM> through the inner tube <NUM> between the inner filter outlet end <NUM> and the inner engine intake end <NUM>. In other words, gas or fluid may flow through the inner tube <NUM> (e.g., within the inner tube passageway <NUM>) between the inner filter outlet end <NUM> and the inner engine intake end <NUM>.

The outer tube <NUM> may be configured to receive the inner tube <NUM> within the outer tube passageway <NUM>. For example, the outer engine intake end <NUM> (e.g., the engine intake end of the outer tube <NUM>) may be configured to receive the inner filter outlet end <NUM> (e.g., the filter outlet end of the inner tube <NUM>). Therefore, filtered air from the air filter outlet <NUM> may pass from the outer tube <NUM> to the inner tube <NUM> and onto the engine intake <NUM>. As such, the outer tube <NUM> and the inner tube <NUM> may overlap such that at least a portion of the interior surface <NUM> of the outer tube <NUM> may face at least a portion of the exterior surface <NUM> of the inner tube <NUM>. The portion of the interior surface <NUM> of the outer tube <NUM> that faces the inner tube <NUM> may be described as an outer pulse portion <NUM> of the interior surface <NUM> of the outer tube <NUM> and the portion of the exterior surface <NUM> of the inner tube <NUM> that faces the outer tube <NUM> may be described as an inner pulse portion <NUM> of the exterior surface <NUM> of the inner tube <NUM>. Therefore, the outer pulse portion <NUM> of the interior surface <NUM> of the outer tube <NUM> may face the inner pulse portion <NUM> of the exterior surface <NUM> of the inner tube <NUM>. The outer and inner pulse portions <NUM>, <NUM> may be the region for which a ring of gas may be formed (e.g., due to a pulse jet apparatus) to clean the filter cartridge/media, as described further herein.

The pulse ring assembly <NUM> may also include a seal <NUM> between the interior surface <NUM> of the outer tube <NUM> and the exterior surface <NUM> of the inner tube <NUM>. For example, the seal <NUM> may be positioned proximate the outer engine intake end <NUM>. The seal <NUM> may be configured to prevent undesired elements from entering the space between the inner tube <NUM> and the outer tube <NUM> (and, e.g., within the clean air space). The seal <NUM> may be any suitable component that may seal the space between the outer tube <NUM> and the inner tube <NUM>.

The pulse ring assembly <NUM> may further include a pulse jet apparatus <NUM> in fluid communication with the pulse port <NUM> of the outer tube <NUM>. The pulse jet apparatus <NUM> may be configured to direct gas or fluid from the pulse port <NUM> of the outer tube <NUM> towards the outer filter outlet end <NUM>. For example, the pulse jet apparatus <NUM> may be configured to direct gas through the pulse port <NUM> and into the outer and inner pulse portions <NUM>, <NUM> of the outer and inner tubes <NUM>, <NUM>. The gas from the pulse jet apparatus <NUM> may then be forced towards the air filter outlet <NUM> (e.g., due to the positioning and configuration of the outer and inner pulse portions <NUM>, <NUM>) to, e.g., clean debris from the outside of the filter cartridge/media (e.g., by pulsing gas from the pulse jet apparatus <NUM> at the inside of the filter cartridge/media).

The pulse jet apparatus may operate in a similar way as described in, e.g., <CIT> entitled "Air Cleaner Having Scavenger Arrangement," <CIT> entitled "Pulse Jet Air Cleaner System; Components; and, Methods," <CIT> entitled "Evacuation Value Arrangements; Pulse Jet Air Cleaner Systems Using Same; and, Method," and <CIT> entitled "Pulse Jet Air Cleaner Systems; Evacuation Valve Arrangements; Air Cleaner Components; and Methods.

The pulse port <NUM> (through which the pulse jet apparatus <NUM> directs gas back towards the air filter outlet <NUM> to clean the filter cartridge) may be positioned along the outer tube <NUM> at a location between the inner filter outlet end <NUM> and the outer engine intake end <NUM>. In other words, the pulse port <NUM> may be positioned anywhere along the length where the outer tube <NUM> and the inner tube <NUM> overlap (e.g., within the outer and inner pulse portions <NUM>, <NUM>). For example, the pulse port <NUM> may be positioned closer to the outer engine intake end <NUM> than the inner filter outlet end <NUM>. In other words, the pulse port <NUM> may be positioned as close to the seal <NUM> as possible to, e.g., prevent extra "dead" space through which gas from the pulse jet apparatus <NUM> may not flow (e.g., because the seal <NUM> may allow flow in only one direction away from the seal). In other embodiments, the pulse port <NUM> may be positioned closer to the inner filter outlet end <NUM> than the outer engine intake end <NUM> or halfway between the inner filter outlet end <NUM> and the outer engine intake end <NUM>.

Furthermore, the pulse port <NUM> may be spaced a distance <NUM> from the inner filter outlet end <NUM> of about <NUM> (e.g., about <NUM> inches) or less measured along the longitudinal axis <NUM>. The distance <NUM> may provide for the gas from the pulse jet apparatus <NUM> to travel through the outer and inner pulse portions <NUM>, <NUM> for the distance <NUM> to direct (e.g., along the longitudinal axis <NUM>) and smooth the flow before it passes towards the air filter outlet <NUM>. In other words, the distance <NUM> may prevent the gas from the pulse jet apparatus <NUM> from immediately passing into the outer tube passageway <NUM> in an undesired direction.

The inner tube and the outer tube of a pulse ring assembly as described herein may define any cross-sectional shape or shapes such that the inner tube may be received by the outer tube. For example, the inner and outer tubes may define a cross-sectional shape that is, e.g., circular, oval, hexagonal, etc. and, further, the inner and outer tubes may have the same or different shapes.

The inner tube <NUM> and the outer tube <NUM> may have diameters in the region in which they overlap such that the inner tube <NUM> may be received by the outer tube <NUM>. The term "diameter" as used herein includes, for non-circular tubes, an effective diameter of the non-circular opening which is the diameter of a circle having the same area as the non-circular opening.

The inner tube <NUM> of one or more embodiments of a pulse ring assembly <NUM> as described herein may define a diameter <NUM> that may be any suitable length. Specifically, the diameter <NUM> of the inner tube <NUM> may be about <NUM> (e.g., about <NUM> inch) or more and/or about <NUM> (e.g., about <NUM> inches) or less. More specifically, the diameter <NUM> of the inner tube <NUM> may be about <NUM> (e.g., about <NUM> inches). Also, for example, the outer tube <NUM> may define a diameter (e.g., a second diameter <NUM>) that may be any suitable distance that may be greater than the diameter <NUM> of the inner tube <NUM>. Specifically, the diameter <NUM> of the outer tube <NUM> may be about <NUM> (e.g., about <NUM> inch) or more and/or about <NUM> (e.g., about <NUM> inches) or less. For example, <FIG> illustrates the diameters <NUM>, <NUM> of the outer and inner tubes <NUM>, <NUM>, respectively. Further, each of the outer and inner tubes <NUM>, <NUM> may define any suitable thickness.

Additionally, the outer tube <NUM> may define multiple diameters along the length of the outer tube <NUM> (e.g., along the longitudinal axis <NUM>). For example, as shown in <FIG>, the outer tube <NUM> may define a first diameter <NUM> (e.g., measured from the interior surface <NUM> of the outer tube <NUM>) proximate the outer filter outlet end <NUM> and the second diameter <NUM> (e.g., as described herein) proximate the outer engine intake end <NUM>. In one or more embodiments, the first and second diameters <NUM>, <NUM> may be different (e.g., such that outer tube <NUM> tapers at a portion between the outer filter outlet end <NUM> and the outer engine intake end <NUM>). For example, the first diameter <NUM> may be less than or equal to the second diameter <NUM>. In other embodiments, the outer tube <NUM> may define a single diameter along the length of the outer tube <NUM> between the outer filter outlet end <NUM> and the outer engine intake end <NUM> (e.g., as shown in <FIG>). Specifically, the first diameter <NUM> of the outer tube <NUM> may be about <NUM> (e.g., about <NUM> inch) or more and/or about <NUM> (e.g., about <NUM> inches) or less.

As described herein, the filtered air (e.g., from the air filter outlet <NUM>) may travel from the outer tube <NUM> to the inner tube <NUM> and then on to the engine intake <NUM>. Therefore, the cross-sectional area of each of the outer tube <NUM> and the inner tube <NUM> may be similar to maintain a consistent flow of air (e.g., pressure or velocity) therebetween. As a result, the first diameter <NUM> of the outer tube <NUM> may be equal to or less than the diameter <NUM> of the inner tube <NUM> to maintain a consistent cross-sectional area. Further, a similar diameter (e.g., the first diameter <NUM> of the outer tube <NUM> and the diameter <NUM> of the inner tube <NUM>) may prevent filtered air from directly going into the space between the outer tube <NUM> and the inner tube <NUM> overlap. In some embodiments, the first diameter <NUM> of the outer tube <NUM> may be greater than the diameter <NUM> of the inner tube <NUM>.

In one or more embodiments of the pulse ring assemblies described herein, the interior surface <NUM> of the outer tube <NUM> and the exterior surface <NUM> of the inner tube <NUM> may be spaced a selected gap distance from one another (e.g., gap distance <NUM> in the depicted embodiments). The gap distance may, in one or more embodiments, be uniform about the perimeter of the inner tube and/or along the length of the region in which the inner tube is positioned within the outer tube. In one or more altemative embodiments, the gap distance may be non-uniform when moving about the perimeter of the inner tube and/or along the length of the region in which the inner tube is positioned within the outer tube.

In one or more embodiments, the gap distance <NUM> between the inner tube <NUM> and the outer tube <NUM> may be about <NUM> (e.g., about <NUM> inches) or more and/or about <NUM> (e.g., about <NUM> inches) or less. In some embodiments, the inner tube <NUM> and the outer tube <NUM> may define concentric cross-sectional shapes (e.g., circular shapes) such that, e.g., the interior surface <NUM> of the outer tube <NUM> and the exterior surface <NUM> of the inner tube <NUM> are the same distance apart for the entirety of the overlapped portion. The gap distance <NUM> may be sealed by the seal <NUM> proximate the outer engine intake end <NUM>, as described herein. Further, a longitudinal gap <NUM> between the inner filter outlet end <NUM> and the outer tube <NUM> extending along the longitudinal axis <NUM> may also assist in controlling the gas flow from the pulse jet apparatus <NUM>. Specifically, the longitudinal gap <NUM> may be about <NUM> (e.g., about <NUM> inches) or more and/or <NUM> (e.g., about <NUM> inches) or less. Further yet, the outer tube <NUM> may taper/expand between the outer filter outlet end <NUM> and the outer engine intake end <NUM> at an angle <NUM> of about <NUM> degrees or more and/or <NUM> degrees or less. Specifically, the angle <NUM> may be about <NUM> degrees. For example, selectively choosing the spacing of the gaps and angles between the inner and outer tubes <NUM>, <NUM> (e.g., the gap distance <NUM>, the longitudinal gap <NUM> measured along the longitudinal axis <NUM>, and the taper of the outer tube <NUM>) may control volume and trajectory of gas delivered by the pulse jet apparatus <NUM> to clean the filter cartridge/media proximate the air filter outlet <NUM>.

It is noted that <FIG> illustrates a cross-sectional schematic and, therefore, gas flowing from the pulse jet apparatus <NUM> would fill the entire annular space between the inner tube <NUM> and the outer tube <NUM> (e.g., the overlap section), and flow towards the air filter outlet <NUM> in a, e.g., ring shape. In other words, gas from the pulse jet apparatus <NUM> would be present between the inner tube <NUM> and the outer tube <NUM> at both of the top and bottom portions of overlap (of the inner and outer tubes <NUM>, <NUM>) as illustrated in <FIG>. For example, as shown in <FIG>, the entire gap distance <NUM> between the inner tube <NUM> and the outer tube <NUM> is in fluid communication with the pulse port <NUM>.

The inner and outer tubes <NUM>, <NUM> of the pulse ring assembly <NUM> may also be arranged as shown in <FIG>. For example, the outer tube <NUM> may define a single diameter along the longitudinal axis <NUM> and the inner tube <NUM> may define multiple diameters to be received within the outer tube <NUM>. Specifically, the portion of the inner tube <NUM> received by the outer tube <NUM> defines a smaller diameter and produces a gap distance <NUM> between the inner and outer tubes <NUM>, <NUM>. The illustrative embodiment shown in <FIG> may include similar features as described herein with respect to other illustrative embodiments (e.g., the pulse port <NUM> is defined by the outer tube <NUM>, seal <NUM> between the inner and outer tubes <NUM>, <NUM>, etc.).

As shown in <FIG>, the pulse ring assembly <NUM> may also include a controller <NUM> operably coupled to the pulse jet apparatus <NUM> (or to air supply sources thereof) and may be configured to selectively activate the pulse jet apparatus <NUM>. For example, the controller <NUM> may be configured to selectively activate the pulse jet apparatus <NUM> such that the gas is directed (e.g., in discrete pulses) from the pulse port <NUM> of the outer tube <NUM> towards the outer filter outlet end <NUM>. The activation of the pulse jet apparatus <NUM> may be in response to any possible signal that the filter cartridge needs cleaning provided by, e.g., a pressure sensor, a light sensor, a timer, etc. For example, the controller <NUM> may be configured to automatically activate the pulse jet apparatus <NUM> in response to a predetermined pressure differential across the filter cartridge (e.g., as determined using a pressure sensor). In other embodiments, the controller <NUM> may be configured to continuously activate the pulse jet apparatus <NUM> for a period of time. The controller <NUM> may be configured to allow for manual activation (e.g., a manual override) of the pulse jet apparatus <NUM> or automatically activate the pulse jet apparatus <NUM>. For example, an operator (e.g., a vehicle operator) may actuate or push a button that is operably connected (e.g., wired or wireless) to the pulse jet apparatus <NUM> (or, e.g., a pulse valve) to manually activate the pulse jet apparatus <NUM>, therefore, the operator will be aware of when the cleaning pulse will occur.

The methods and/or logic described in this disclosure, including those attributed to the pulse ring assembly <NUM>, or various constituent components (e.g., the controller <NUM>), may be implemented, at least in part, in hardware, software, firmware, or any combination thereof. For example, various aspects of the techniques may be implemented within one or more processors, including one or more microprocessors, microcontrollers, DSPs, ASICs, FPGAs, or any other equivalent integrated or discrete logic circuitry, as well as any combinations of such components, or other devices. Such hardware, software, and/or firmware may be implemented within the same system or within separate systems to support the various operations and functions described in this disclosure. In addition, any of the described components may be implemented together or separately as discrete but interoperable logic devices.

When implemented in software, the functionality ascribed to the systems, devices and methods described in this disclosure may be embodied as instructions and/or logic on a computer-readable medium such as RAM, ROM, NVRAM, EEPROM, FLASH memory, magnetic data storage media, optical data storage media, or the like. The instructions and/or logic may be executed by one or more processors to support one or more aspects of the functionality described in this disclosure.

<FIG> illustrates a flow chart depicting a method <NUM> of retrofitting a pulse ring assembly (e.g., pulse ring assembly <NUM>) between an air filter outlet (e.g., air filter outlet <NUM>) and an engine intake (e.g., engine intake <NUM>). The method <NUM> may include connecting <NUM> an outer tube (e.g., outer tube <NUM>) to the air filter outlet. The outer tube may be connected to the air filter outlet in any suitable way. The outer tube may extend between an outer filter outlet end connected to the air filter outlet and an outer engine intake end. The outer tube may include an interior surface and an exterior surface. The interior surface of the outer tube may define an outer tube passageway through the outer tube between the outer filter outlet end and the outer engine intake end. The outer tube may include a pulse port extending between the interior and exterior surfaces into the outer tube passageway.

The method <NUM> may also include positioning <NUM> an inner tube (e.g., inner tube <NUM>) within the outer tube passageway. The inner tube may extend along a longitudinal axis between an inner filter outlet end and an inner engine intake end. The inner tube may include an interior surface and an exterior surface. The interior surface of the inner tube may define an inner tube passageway through the inner tube between the inner filter outlet end and the inner engine intake end. The inner filter outlet end may be positioned within the outer tube passageway such that an outer pulse portion of the interior surface of the outer tube faces the exterior surface of the inner tube. Filtered air may be configured to flow from the air filter outlet to the engine intake. The method <NUM> may also include connecting <NUM> the inner engine intake end to the engine intake (e.g., the inner tube may be connected to the engine intake in any suitable way) and connecting <NUM> a pulse jet apparatus (e.g., pulse jet apparatus <NUM>) in fluid communication with the pulse port of the outer tube. The pulse jet apparatus may be configured to direct gas from the pulse port of the outer tube towards the outer filter outlet end.

In one or more embodiments, the method <NUM> may further include manually operating the pulse jet apparatus to direct gas from the pulse port of the outer tube towards the outer filter outlet end or operating the pulse jet apparatus to direct gas from the pulse port of the outer tube towards the outer filter outlet end, e.g., when (or in response to) a predetermined pressure differential across a filter cartridge proximate the air filter outlet is reached. In one or more embodiments, the method <NUM> may also include selectively activating the pulse jet apparatus. For example, selectively activating the pulse jet apparatus may include directing gas in spaced-apart pulses from the pulse port of the outer tube towards the outer filter outlet end.

Additionally, <FIG> illustrate another embodiment of a pulse ring assembly <NUM> that may be used in one or more embodiment of an air cleaner system as described herein. It is noted that the elements described with respect to <FIG> also apply to the pulse ring assembly <NUM>. As shown in <FIG> and <FIG>, an air cleaner housing <NUM> may include an inlet <NUM> and an outlet tube <NUM>. The outlet tube <NUM> may be operably connected to an engine intake such that the outlet tube <NUM> and the engine intake are in fluid communication. Air external to the air cleaner housing <NUM> may enter the inlet <NUM>, passing through filter elements contained within the air cleaner housing <NUM>, and exiting through the outlet tube <NUM> to the engine intake. Therefore, air entering the inlet <NUM> may be filtered (e.g., through the filter elements) and pass to the engine through the engine intake.

As shown in <FIG>, the outlet tube <NUM> may be described as an inner tube <NUM> (e.g., similar to the inner tube <NUM> of <FIG>) that extends into the air cleaner housing <NUM>. For example, the inner tube <NUM> may extend along a longitudinal axis <NUM> between an inner filter outlet end <NUM> and an inner engine intake end <NUM>. The inner engine intake end <NUM> may be adapted to be operably coupled to an engine intake. The inner tube <NUM> may include an interior surface <NUM> and an exterior surface <NUM>. The interior surface <NUM> of the inner tube <NUM> may define an inner tube passageway <NUM> through the inner tube <NUM> between the inner filter outlet end <NUM> and the inner engine intake end <NUM>.

Further, the pulse ring assembly <NUM> may include an outer tube <NUM> extending between an outer filter outlet end <NUM> and an outer engine intake end <NUM>. The outer tube <NUM> may include an interior surface <NUM> and an exterior surface <NUM>. The interior surface <NUM> of the outer tube <NUM> may define an outer tube passageway <NUM> through the outer tube <NUM> between the outer filter outlet end <NUM> and the outer engine intake end <NUM>. The outer tube passageway <NUM> may receive the inner tube <NUM> (e.g., the inner filter outlet end <NUM>) such that at least a portion of the interior surface <NUM> of the outer tube <NUM> faces at least a portion of the exterior surface <NUM> of the inner tube <NUM>.

The inner tube <NUM> and the outer tube <NUM> may extend into the air cleaner housing <NUM> and may be sealed to the air cleaner housing <NUM> such that air passing through the inner tube passageway <NUM> must first pass through filter elements (e.g., as will be described further herein) located within the air cleaner housing <NUM>. The inner tube <NUM> and the outer tube <NUM> may extend into the housing <NUM> an equal distance (e.g., such that the inner filter outlet end <NUM> and the outer filter outlet end <NUM> are flush or even along the longitudinal axis <NUM>). In other embodiments, the outer filter outlet end <NUM> may extend into the housing <NUM> farther than the inner filter outlet end <NUM> (e.g., as shown in <FIG>) or the inner filter outlet end <NUM> may extend into the housing <NUM> farther than the outer filter outlet end <NUM>.

Further, the outer tube <NUM> may include a pulse port <NUM> extending between the interior and exterior surfaces <NUM>, <NUM> of the outer tube <NUM> (e.g., an opening in the outer tube <NUM>) into the outer tube passageway <NUM>. The pulse port <NUM> may be in fluid communication with a space between the inner and outer tubes <NUM>, <NUM> such that gas directed into the pulse port <NUM> may take the shape of the gap between the inner and outer tubes <NUM>, <NUM>. For example, the area between the inner and outer tubes <NUM>, <NUM> may form a ring (e.g., an annular shape) such that gas directed through the pulse port <NUM> forms a ring-shaped flow of gas towards the filter elements within the housing <NUM>.

The air cleaner housing <NUM> may include a first filter cartridge <NUM> (e.g., a safety filter element) surrounding the inner and outer tubes <NUM>, <NUM>, and a second filter cartridge <NUM> (e.g., a primary filter element) surrounding the first filter cartridge <NUM>. As such, air entering the inlet <NUM> passes through the second filter cartridge <NUM> and then the first filter cartridge <NUM>, before passing through the inner tube <NUM> to the engine intake. In some embodiments, the first filter cartridge <NUM> may include smaller filter media openings than the second filter cartridge <NUM> such that the second filter cartridge <NUM> (e.g., the primary filter element) is designed to capture a large portion of the debris and sediment entering the inlet <NUM> and the first filter cartridge <NUM> (e.g., the safety filter element) is designed to capture other debris and sediment that may have passed through the second filter cartridge <NUM>. Each of the first and second filter cartridges <NUM>, <NUM> may include a first and second cap <NUM>, <NUM>, respectively, to seal the filter cartridges such that air only passes through the filter elements of the first and second filter cartridges <NUM>, <NUM> before entering inner tube <NUM>.

The pulse port <NUM> may be in fluid communication within the first filter cartridge <NUM> such that gas directed through the pulse port <NUM> may apply pressure to an interior surface of the first filter cartridge <NUM> to, e.g., push debris and sediment off the exterior surface of the first filter cartridge <NUM>. Additionally, in one or more embodiments, multiple pulse ports may be incorporated into the pulse ring assembly <NUM> to clean various filter elements located within the air cleaner system <NUM>. For example, as shown in <FIG>, the housing <NUM> may define an additional pulse port <NUM> positioned between the first and second filter cartridges <NUM>, <NUM>. As such, gas directed through the additional pulse port <NUM> may take the shape of the gap between the first and second filter cartridges <NUM>, <NUM>. For example, the area between the first and second filter cartridges <NUM>, <NUM> may form a ring (e.g., an annular shape) such that gas directed through the additional pulse port <NUM> forms a ring-shaped flow between the first and second filter cartridges <NUM>, <NUM>.

The gas directed through the additional pulse port <NUM> may be used to clean debris and sediment from the second filter cartridge <NUM>. For example, the gas directed through the additional pulse port <NUM> may apply a force to an interior surface of the second filter cartridge <NUM> to push sediment and debris off an exterior surface of the second filter cartridge <NUM>. Further, the gas directed through the additional pulse port <NUM> may provide a pressure barrier to improve the cleaning effectiveness of the gas directed through the pulse port <NUM>. For example, gas directed through the additional pulse port <NUM> may create a lower pressure along the exterior surface of the first filter cartridge <NUM> such that gas directed through the pulse port <NUM> may more effectively push debris and sediment from the exterior surface of the first filter cartridge <NUM>. Additionally, the gas directed through each of the pulse port <NUM> and the additional pulse port <NUM> may be controlled individually or together. For example, in one or more embodiments, the pulse ring assembly <NUM> may include a valve (e.g., a diaphragm valve (e.g., with solenoid activation), a poppet valve, etc.) or other flow control elements (e.g., orifices, etc.) to control the velocity, volume, pressure, etc. of the gas directed through each of the pulse port <NUM> and the additional pulse port <NUM>. Also, the gap between the first and second filter cartridges <NUM>, <NUM> and the gap between the inner and outer tubes <NUM>, <NUM> may be sized to precisely control the volumetric flow of gas through each of the additional pulse port <NUM> and the pulse port <NUM>, respectively.

Additionally, the air cleaner system <NUM> may include a pulse jet apparatus <NUM> in fluid communication with the pulse port <NUM> and the additional pulse port <NUM>. The pulse jet apparatus <NUM> may be configured to direct gas through the pulse port <NUM> and/or the additional pulse port <NUM>. For example, as described herein, the pulse jet apparatus <NUM> may direct gas through the pulse port <NUM> and the additional pulse port <NUM> independently or together. Further, the pulse jet apparatus <NUM> may be controlled or operate similar to the pulse jet apparatus <NUM> as described in reference to <FIG>.

In the preceding description, reference is made to the accompanying set of drawings that form a part hereof and in which are shown by way of illustration several specific embodiments. It is to be understood that other embodiments are contemplated and may be made without departing from (e.g., still falling within) the scope of the present disclosure. The preceding detailed description, therefore, is not to be taken in a limiting sense.

Unless otherwise indicated, all numbers expressing feature sizes, amounts, and physical properties used in the specification and claims are to be understood as being modified in all instances by the term "about. " Accordingly, unless indicated to the contrary, the numerical parameters set forth in the foregoing specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by those skilled in the art utilizing the teachings disclosed herein.

As used herein, "have", "having", "include", "including", "comprise", "comprising" or the like are used in their openended sense, and generally mean "including, but not limited to". It will be understood that "consisting essentially of", "consisting of", and the like are subsumed in "comprising," and the like.

It is noted that terms such as "top", "bottom", "above, "below", etc. may be used in this disclosure. These terms should not be construed as limiting the position or orientation of a structure, but should be used as providing spatial relationship between the structures.

Claim 1:
A method of retrofitting a pulse ring assembly between an air filter outlet of an air cleaner system and an engine intake, the method comprising:
connecting an outer tube (<NUM>; <NUM>) to the air filter outlet, wherein the outer tube (<NUM>; <NUM>) extends between an outer filter outlet end (<NUM>; <NUM>) connected to the air filter outlet and an outer engine intake end (<NUM>; <NUM>), wherein the outer tube (<NUM>; <NUM>) comprises an interior surface (<NUM>; <NUM>) and an exterior surface (<NUM>; <NUM>), wherein the interior surface (<NUM>; <NUM>) of the outer tube defines an outer tube passageway (<NUM>; <NUM>) through the outer tube (<NUM>; <NUM>) between the outer filter outlet end (<NUM>; <NUM>) and the outer engine intake end (<NUM>; <NUM>), wherein the outer tube (<NUM>; <NUM>) comprises a pulse port (<NUM>; <NUM>) extending between the interior and exterior surfaces into the outer tube passageway (<NUM>; <NUM>);
positioning an inner tube (<NUM>; <NUM>) within the outer tube passageway (<NUM>; <NUM>), wherein the inner tube (<NUM>; <NUM>) extends along a longitudinal axis between an inner filter outlet end (<NUM>; <NUM>) and an inner engine intake end (<NUM>; <NUM>), wherein the inner tube (<NUM>; <NUM>) comprises an interior surface (<NUM>; <NUM>) and an exterior surface (<NUM>; <NUM>), wherein the interior surface (<NUM>; <NUM>) of the inner tube (<NUM>; <NUM>) defines an inner tube passageway (<NUM>; <NUM>) through the inner tube between the inner filter outlet end (<NUM>; <NUM>) and the inner engine intake end (<NUM>; <NUM>), wherein the inner filter outlet end (<NUM>; <NUM>) is positioned within the outer tube passageway (<NUM>; <NUM>) such that an outer pulse portion of the interior surface (<NUM>; <NUM>) of the outer tube (<NUM>; <NUM>) faces the exterior surface (<NUM>; <NUM>) of the inner tube (<NUM>; <NUM>), wherein filtered air is configured to flow from the air filter outlet to the engine intake;
connecting the inner engine intake end (<NUM>; <NUM>) to the engine intake; and
connecting a pulse jet apparatus (<NUM>; <NUM>) in fluid communication with the pulse port (<NUM>; <NUM>) of the outer tube, wherein the pulse jet apparatus is configured to direct gas from the pulse port of the outer tube towards the outer filter outlet end.