System and method for aspirating a pre-cleaner of a work vehicle using a double-walled flow pipe

A system for aspirating a pre-cleaner of a work vehicle may include a fluid conduit in flow communication with an outlet port of the pre-cleaner for receiving an aspirated airflow from the pre-cleaner. The system may also include a double-walled flow pipe having an inner tube that receives a primary fluid flow of the work vehicle. The double-walled flow pipe may also include an outer tube surrounding the inner tube such that an annular passage is defined between the inner and outer tubes. The annular passage may be in flow communication with the fluid conduit. When a vacuum is applied to the annular passage, the aspirated airflow may be drawn through the fluid conduit from the pre-cleaner and directed to the annular passage. The aspirated airflow flows through the annular passage as the primary fluid flow is being directed through the inner tube.

FIELD OF THE INVENTION

The present subject matter relates generally to work vehicles and, more particularly, to a system and method for aspirating a pre-cleaner of a work vehicle using a dual-function, double-walled flow pipe for transporting an aspirated airflow from the pre-cleaner.

BACKGROUND OF THE INVENTION

Work vehicles typically include internal combustion engines that require clean air for use within the combustion process. Since many work vehicles, such as tractors and other agricultural vehicles, operate in fields and other harvesting environments in which the ambient air contains large amounts of dust, plant material and other particulates, an air intake system having an effective filter assembly is required. For example, conventional filter assemblies for work vehicles typically include a vortex or cyclone pre-cleaner configured to separate large particulates from the intake air and a porous air filter downstream of the pre-cleaner to provide the final stage of filtering prior to delivering the air into the engine.

To prevent the air filter from clogging, the large particulates separated from the intake air by the pre-cleaner must be removed from the filter assembly. Typically, such particulates are removed from the filter assembly via an outlet duct using a vacuum generated by the exhaust flow from the engine. However, to couple the outlet duct to the exhaust flow, one or more separate tubes and/or hoses must be provided between the filter assembly and the exhaust pipe through which the exhaust flow is being directed. Such tube(s)/hose(s) are often of considerable length and take up valuable packaging space within the interior of the work vehicle.

Accordingly, an improved system and method for aspirating a pre-cleaner of a work vehicle that allows for the number and/or length of the separate tube(s)/hose(s) coupled between the pre-cleaner and a vacuum source to be reduced would be welcomed in the technology.

BRIEF DESCRIPTION OF THE INVENTION

In one aspect, the present subject matter is directed to a system for aspirating a pre-cleaner of a work vehicle. The system may generally include a fluid conduit configured to be in flow communication with an outlet port of the pre-cleaner for receiving an aspirated airflow from the pre-cleaner. The system may also include a double-walled flow pipe having an inner tube configured to receive a primary fluid flow of the work vehicle, wherein the primary fluid flow differs from the aspirated airflow. The double-walled flow pipe may also include an outer tube surrounding the inner tube such that an annular passage is defined between the inner and outer tubes. The annular passage may be in flow communication with the fluid conduit. When a vacuum is applied to the annular passage, the aspirated airflow may be drawn through the fluid conduit from the pre-cleaner and directed to the annular passage. The aspirated airflow flows through the annular passage as the primary fluid flow is being directed through the inner tube.

In another aspect, the present subject matter is directed to a system for aspirating a pre-cleaner of a work vehicle. The system may include a fluid conduit configured to be in flow communication with an outlet port of the pre-cleaner for receiving an aspirated airflow from the pre-cleaner. The system may also include a double-walled flow pipe having an inner tube configured to receive an exhaust flow of the work vehicle and an outer tube surrounding the inner tube such that an annular passage is defined between the inner and outer tubes. The inner tube may include a venturi section and the annular passage may be in flow communication with the fluid conduit. The double-walled flow pipe may also include a vacuum tube providing a flow path between the annular passage and the venturi section of the inner tube. When the exhaust flow is directed through the venturi section, a vacuum may be generated within the vacuum tube that draws the aspirated airflow through the fluid conduit to the annular passage. Thereafter, the aspirated airflow flows through the annular passage to the vacuum tube and may be expelled therefrom into the exhaust flow through the inner tube.

In a further aspect, the present subject matter is directed to a method for aspirating a pre-cleaner of a work vehicle. The method may include applying a vacuum to an annular passage of a double-walled flow pipe that is in fluid communication with an outlet of the pre-cleaner. The double-walled flow pipe may include an inner tube and an outer tube surrounding the inner tube such that the annular passage is defined between the inner and outer tubes. The inner tube may be configured to receive a primary fluid flow of the work vehicle. The method may also include generating an aspirated airflow via the vacuum that is directed from the outlet of the pre-cleaner to the annular passage and flows through the annular passage as the primary fluid flow is flowing through the inner tube.

DETAILED DESCRIPTION OF THE INVENTION

In general, the present subject matter is directed to a system and method for aspirating a pre-cleaner of a work vehicle. Specifically, in several embodiments, the system may include a double-walled flow pipe including concentric tubes (e.g., an inner tube and an outer tube) such that an inner flow path is defined by the inner tube and an outer flow path is formed within the annular passage defined between the inner and outer tubes. In such embodiments, a primary fluid flow of the work vehicle may be directed along the inner flow path (e.g., an exhaust gas flow or a liquid coolant flow) while an aspirated airflow from the pre-cleaner may be directed through the outer flow path. For instance, the annular passage defined between the inner and outer tubes may be provided in flow communication with an outlet port of the pre-cleaner via a fluid coupling. As such, by applying a vacuum to the annular passage and the fluid coupling, the particulates separated within the pre-cleaner may be expelled therefrom as an aspirated airflow and may flow through the fluid coupling and along the annular passage as the primary fluid flow is being directed through the inner flow path.

By providing the dual-function, double-walled flow pipe, the number and/or length of the hose(s)/tube(s) typically required in a conventional aspiration system may be reduced. For instance, by directing the aspirated airflow through the annular passage of the double-walled flow pipe a given lengthwise distance, a length(s) of any associated separate hose(s)/tube(s) of the system may be reduced a corresponding amount. As a result, the costs associated with the hose(s)/tube(s) may be reduced. In addition, the amount of packaging space occupied by such hose(s)/tube(s) within the work vehicle may be similarly reduced.

Referring now to the drawings,FIG. 1illustrates a side view of one embodiment of a work vehicle10. As shown, the work vehicle10is configured as an agricultural tractor. However, in other embodiments, the work vehicle10may be configured as any other suitable work vehicle known in the art, such as various other agricultural vehicles, earth-moving vehicles, road vehicles, loaders and/or the like.

As shown inFIG. 1, the work vehicle10includes a pair of front wheels12, a pair or rear wheels14and a chassis16coupled to and supported by the wheels12,14. An operator's cab18may be supported by a portion of the chassis16and may house various control devices20(e.g., levers, pedals, control panels and/or the like) for permitting an operator to control the operation of the work vehicle10. Additionally, the work vehicle10may include an engine22and a transmission24mounted on the chassis16. The transmission24may be operably coupled to the engine22and may provide variably adjusted gear ratios for transferring engine power to the wheels14via a differential26. The engine22, transmission24, and differential26may collectively define a drivetrain of the work vehicle10.

Moreover, the work vehicle10may also include an exhaust treatment system28for reducing the amount emissions contained within the engine exhaust. For instance, engine exhaust expelled from the engine22may be directed through a first exhaust pipe30to the exhaust treatment system28to allow the levels of nitrous oxide (NOx) emissions contained within the exhaust to be reduced significantly. The cleaned exhaust gases may then be expelled from the exhaust treatment system28into the surrounding environment via a second exhaust pipe32of the work vehicle10.

It should be appreciated that the configuration of the work vehicle10described above and shown inFIG. 1is provided only to place the present subject matter in an exemplary field of use. Thus, it should be appreciated that the present subject matter may be readily adaptable to any manner of work vehicle configuration10. For example, in an alternative embodiment, a separate frame or chassis may be provided to which the engine22, transmission24, and differential26are coupled, a configuration common in smaller tractors. Still other configurations may use an articulated chassis to steer the work vehicle10, or rely on tracks in lieu of the wheels12,14. Additionally, although not shown, the work vehicle10may also be configured to be operably coupled to any suitable type of work implement, such as a trailer, spray boom, manure tank, feed grinder, plow and/or the like.

Referring now toFIG. 2, a schematic view of one embodiment of a system100for aspirating a pre-cleaner of a work vehicle10is illustrated in accordance with aspects of the present subject matter. In general, the system100will be described herein with reference to the work vehicle10shown inFIG. 1. However, it should be appreciated that the disclosed system100may generally be utilized with any suitable work vehicle having any suitable vehicle configuration.

As shown inFIG. 2, the system100may include or be associated with various components of an air intake system of the work vehicle10. For example, the system100may include a filter assembly102configured to receive dirty air from an intake duct104and clean/filter such air for subsequent delivery to the engine22. In general, the filter assembly102may include a pre-cleaner106and an air filter108disposed downstream of the pre-cleaner106. In addition, the filter assembly102may include a pre-cleaner housing110configured to encase the pre-cleaner106and a filter housing112configured to encase the air filter108. It should be appreciated that the pre-cleaner housing110and the filter housing112may be formed integrally with one another (e.g., by forming both housings110,112as a single continuous housing) or the pre-cleaner housing110and the filter housing112may comprise separate components configured to be separately coupled to one another.

As is generally understood, the pre-cleaner106may be configured to remove portions of the dust, dirt, debris, plant matter and other particulates contained within the air flowing into the filter assembly102via the intake duct104. Specifically, in several embodiments, the pre-cleaner106may include a plurality of tubes (e.g., turbo tubes), dirt separators, and/or any other suitable pre-cleaner elements114configured to separate particulates from the air via centripetal force. For example, the pre-cleaner elements114may be configured to impart a vortex or spinning motion to the flow of air entering the filter assembly102. As a result, large particulates contained within the air may be forced radially outwardly along the inner wall of the pre-cleaner housing110by the centripetal force of the vortex/spinning motion. These large particulates may then be expelled from the filter assembly102via an outlet port116defined in the pre-cleaner housing110.

Additionally, the air filter108may generally be configured to receive the cleaned air flowing from the pre-cleaner106and filter such air to provide a final stage of filtering prior to delivery of the air to the engine22. Thus, as shown inFIG. 2, the air filter108may generally include one or more filter elements118configured to catch or trap the remaining particulates contained within the cleaned air. For instance, in several embodiments, the filter element(s)118may be made from a fibrous, porous or mesh material that allows air to pass therethrough while catching/trapping any particulates. The cleaned/filtered air may then be directed through a suitable conduit120to the engine22, where the air may be mixed with fuel and combusted.

Referring still toFIG. 2, the system100may also include a fluid conduit140in flow communication between the pre-cleaner106and a double-walled flow pipe142to provide a flow path for directing an aspirated airflow (indicated by the labeled, solid arrows144inFIG. 2) from the pre-cleaner106to the double-walled flow pipe142. Specifically, as shown inFIG. 2, the fluid conduit140may include a first end146in flow communication with the outlet port116of the pre-cleaner106and a second end148in flow communication with an aspiration port150defined in the double-walled flow pipe142. As such, the aspirated airflow144expelled from the outlet port116of the pre-cleaner106(including the particulates expelled therefrom) may be directed through fluid conduit140to the double-walled flow pipe142.

It should be appreciated that, as described herein, the fluid conduit140may be formed from a single flow conduit defining a flow path between the pre-cleaner106and the double-walled flow pipe142or the fluid conduit140may be formed from two or more flow conduits coupled together to define a flow path between the pre-cleaner106and the double-walled flow pipe142.

As shown inFIG. 2, the double-walled flow pipe142may generally include an inner tube152and an outer tube154surrounding the inner tube152such that an annular passage156is defined between the inner and outer tubes152,154. The inner tube152may generally be configured to receive a primary fluid flow of the work vehicle10(indicated by dashed arrows158), including any suitable gas flow associated with the work vehicle10and/or any suitable liquid flow associated with the work vehicle10. Specifically, in one embodiment, the primary fluid flow158may correspond to an engine exhaust flow of the work vehicle10. In such an embodiment, the inner tube152may, for example, correspond to all or a portion of one of the exhaust pipes of the work vehicle10(e.g., exhaust pipes30,32shown inFIG. 1) or the inner tube152may be provided in flow communication with such engine exhaust pipes. In another embodiment, the primary fluid flow158may correspond to a compressed airflow of the work vehicle10, such as a compressed charge airflow of the work vehicle10. Alternatively, the primary fluid flow158may correspond to a liquid coolant flow of the work vehicle10. For instance, the primary fluid flow158may include water, oil, refrigerant, or any other suitable liquid coolant utilized within the work vehicle10.

Additionally, the annular passage156defined between the inner and outer tubes152,154may generally be configured to receive the aspirated airflow144from the pre-cleaner106. Specifically, in several embodiments, the aspiration port150may be defined through the outer tube154of the double-walled flow pipe142, thereby providing a flow path between the fluid conduit140and the annular passage156. The aspirated airflow144directed through the fluid conduit140may then enter the double-walled flow pipe142and flow in a flow direction (indicated by arrow160) through the annular passage156as the primary fluid flow158is flowing through the inner tube152.

As will be described below, the annular passage156may provide a flow path for coupling the fluid conduit140(and, thus, the pre-cleaner106) to a downstream vacuum source that is configured to apply a vacuum within the flow path that generates the aspirated airflow144by sucking the particulates flowing along the inner wall of the pre-cleaner housing110out the outlet port116and through the fluid conduit140. For instance, in one embodiment, the vacuum source may be incorporated within the double-walled flow pipe142, such as by including a venturi section within the inner tube152. Alternatively, the vacuum source may be located separate or spaced apart from the lengthwise portion of the double-walled flow pipe142along which the aspirated airflow144is being directed. For instance, as will be described below with reference toFIG. 4, in one embodiment, the double-walled flow pipe144may include a vacuum port288downstream of the aspiration port150through which the aspirated airflow144is expelled from the double-walled flow pipe142as it is being directed towards the vacuum source.

Given this configuration, the double-walled flow pipe142may serve a dual-function. Specifically, the inner tube152of the double-walled flow pipe142may provide a flow path for the primary fluid flow158of the work vehicle10. Additionally, the annular passage156defined between the inner and outer tubes152,154may serve as a flow path for the aspirated airflow144directed between the pre-cleaner106and the vacuum source being applied through the flow path. As a result, the number and/or length of the fluid hoses and/or other couplings typically used to fluidly couple the pre-cleaner106to the vacuum source may be reduced, which may reduce the overall cost of the aspiration system and/or provide additional packaging space within the work vehicle10.

Referring now toFIG. 3, a cross-sectional view of one embodiment of a suitable configuration of a portion of the double-walled flow pipe142described above with reference toFIG. 2is illustrated in accordance with aspects of the present subject matter. In this regard, the same reference characters used inFIG. 2will be used to identify the same or similar components ofFIG. 3. As described above, the double-walled flow pipe142may include an inner tube152and an outer tube154surrounding the inner tube152such that an annular passage156is defined between the inner and outer tubes152,154. Additionally, the double-walled flow pipe142may include an aspiration port150defined through the outer tube154for receiving an aspirated airflow (indicated solid arrows144) directed through a fluid conduit140from the pre-cleaner106(FIG. 2).

In several embodiments, a vacuum source may be incorporated into the double-walled flow pipe142for generating a vacuum to be applied to the annular passage156and the fluid conduit140for sucking particulates out of the pre-cleaner106. As shown inFIG. 3, in one embodiment, the vacuum source may correspond to a venturi section170included within the inner tube152. The venturi section170may generally be formed by a converging section172along which the cross-sectional flow area of the inner tube152is reduced from its upstream flow area and a diverging section174downstream of the converging section172along which the cross-sectional flow area of the inner tube152is increased (e.g., back to the original upstream flow area). Such narrowing of the cross-sectional flow area of the inner tube152results in the flow velocity of the primary fluid flow (indicated by dashed arrows158) increasing through the venturi section170, thereby creating an area of low pressure within the venturi section170that may be used to generate a vacuum.

It should be appreciated that the venturi section170may be formed from any suitable structure and/or component. For example, in the illustrated embodiment, the venturi section170is formed integrally with the inner tube152. In another embodiment, the venturi section170may correspond to a separate component(s) coupled to the inner tube152to form the desired venturi.

As shown inFIG. 3, the double-walled flow pipe152may also include a vacuum tube176to provide a fluid coupling between the annular passage156and the venturi section170, thereby allowing the low pressure area formed within the venturi section170to be applied as a vacuum through the annular passage156. Specifically, the vacuum tube176may extend between an inlet178defined through the inner tube152and an outlet180positioned within the venturi section170. For example, the outlet180may be configured to be generally aligned with the narrowed section of the flow path defined between the converging and diverging sections172,174of the venturi section170. As such, the low pressure area with the venturi section170may apply a vacuum at the outlet180of the vacuum tube176, which may, in turn, be applied to the flow path defined by the annular passage156and the fluid conduit140coupled thereto. Accordingly, the vacuum may serve to generate the aspirated airflow144at the outlet port116of the pre-cleaner106(FIG. 2). The aspirated airflow144(including the expelled particulates) may then be directed through the fluid conduit140and into the annular passage156via the aspirator port150. The aspirated airflow144flowing through the annular passage156may then flow along a lengthwise distance182defined between the aspirator port150and the downstream inlet178of the vacuum tube176prior to entering the vacuum tube176. Thereafter, the aspirated airflow144may be expelled from the outlet180of the vacuum tube176into the primary fluid flow158flowing through the inner tube152.

It should be appreciated that, in the illustrated embodiment, it may be desirable for the primary fluid flow158to correspond to a fluid flow that is being expelled from the work vehicle10. For instance, in several embodiments, the primary fluid flow158may correspond to the exhaust gas flow from the engine22(FIG. 2). In such an embodiment, the aspirated airflow144(including the particulates) may be expelled from the vacuum tube176and mixed with the engine exhaust flow. The mixture of the aspirated airflow144and the engine exhaust flow may then be expelled from the work vehicle10(e.g., via the exhaust pipe32shown inFIG. 1).

It should also be appreciated that the double-walled flow pipe may also be configured to include suitable sealing mechanisms184provided between the inner and outer tubes152,154to minimize losses of the vacuum within the annular passage156and to ensure that the aspirated airflow144is directed from the fluid conduit140to the vacuum tube176. In one embodiment, the sealing mechanisms184may be configured to form a slip joint so as to provide the desired sealing while also allowing relative motion between the inner and outer tubes152,154.

Referring now toFIG. 4, a cross-sectional view of another embodiment of a suitable configuration of a portion of the double-walled flow pipe142described above with reference toFIG. 2is illustrated in accordance with aspects of the present subject matter. In this regard, the same reference characters used inFIG. 2will be used to identify the same or similar components ofFIG. 4. As described above, the double-walled flow pipe142may include an inner tube152and an outer tube154surrounding the inner tube152such that an annular passage156is defined between the inner and outer tubes152,154. Additionally, the double-walled flow pipe142may include an aspiration port150defined through the outer tube154for receiving an aspirated airflow (indicated solid arrows144) directed through a fluid conduit140from the pre-cleaner106(FIG. 2).

As shown inFIG. 4, unlike the embodiment described above with reference toFIG. 3, the double-walled flow pipe142is configured to serve primarily as a flow path for the aspirated airflow144between the fluid conduit140and a downstream vacuum source286. Specifically, in several embodiments, the double-walled flow pipe142may include a vacuum port288located downstream of the aspirator port150. As shown inFIG. 4, the vacuum port288may be defined through the outer tube154and may be in flow communication with a vacuum tube290providing a flow path between the vacuum port288and the vacuum source286. Thus, the aspirated airflow144flowing through the fluid conduit140from the pre-cleaner106may be directed into the annular passage156via the aspirator port150. The aspirated airflow144flowing through the annular passage156may then flow along a lengthwise distance292defined between the aspirator port150and the downstream vacuum port288as the primary fluid flow (indicated by dashed arrows158) is flowing through the inner tube152. Thereafter, the aspirated airflow144may be expelled from the double-walled flow tube142via the vacuum port288and flow through vacuum tube290towards the downstream vacuum source286.

It should be appreciated that, in the embodiment shown inFIG. 3, the vacuum source286may correspond to any suitable vacuum source to which the vacuum tube290may be fluidly coupled. For instance, in one embodiment, the vacuum source286may correspond to a venturi section formed in a separate pipe or tube of the work vehicle10. Alternatively, the vacuum source286may correspond to a venturi section formed in a downstream portion of the double-walled flow pipe142. For example, the portion of the double walled flow pipe142shown inFIG. 3may correspond to a downstream portion of the double-walled flow pipe142shown inFIG. 4. In such an embodiment, the vacuum tube290shown inFIG. 4may provide a flow path between the vacuum port288and the aspirator port150shown inFIG. 3.

In another embodiment, the vacuum source286may correspond to any other suitable vacuum source. For instance, the vacuum source286may correspond to a specific aspirator device, such as a blower, fan module, or vacuum pump, that is configured to be fluidly coupled to the double-walled flow pipe142via the vacuum tube290. Alternatively, the vacuum source286may correspond to another component of the work vehicle10. For instance, the vacuum source286may correspond to a cooling fan of the work vehicle10, such as the fan positioned adjacent to the heat exchangers of the work vehicle10. In such an embodiment, the vacuum tube290may be fluidly coupled between the double-walled flow pipe142and the fan (e.g., by placing the vacuum tube290in flow communication with a port or opening defined in a fan shroud surrounding the fan) to allow the vacuum generated by the fan to be used to aspirate the pre-cleaner106.

Similar to the embodiment described above with reference toFIG. 3, it should be appreciated that the double-walled flow pipe142may be configured to include suitable sealing mechanisms184between the inner and outer tubes152,154to minimize loss of the vacuum within the annular passage156and to ensure that the aspirated airflow144is directed from the fluid conduit140to the vacuum tube290. As indicated above, in one embodiment, the sealing mechanisms184may be configured to form a slip joint so as to provide the desired sealing while also allowing relative motion between the inner and outer tubes152,154.

As indicated above, it should be appreciated that the present subject matter is also directed to a method for aspirating a pre-cleaner106of a work vehicle10. In several embodiments, the method may include applying a vacuum to an annular passage156of a double-walled flow pipe142that is in fluid communication with an outlet116of the pre-cleaner106. In addition, the method may include generating an aspirated airflow144via the vacuum that is directed from the outlet116of the pre-cleaner106to the annular passage156and flows through the annular passage156as a primary fluid flow158is flowing through an inner tube152of the double-walled flow pipe142. Moreover, in one embodiment, the method may include directing the aspirated airflow144into the inner tube152such that the aspirated airflow144is mixed with the primary fluid flow158flowing through the inner tube152. Similarly, in one embodiment, the method may include expelling the aspirated airflow144from the double-walled flow pipe142via a vacuum port288defined through an outer tube154of the double-walled flow pipe142.