Active precleaner system and method of use

Abstract

An air cleaner assembly for filtering the intake air of a power plant includes a filter cartridge disposed within a housing of the air cleaner assembly, a precleaner assembly including at least one particulate separator for separating particulate matter from an air flow stream and a collection port for discharging the separated particulate matter, the precleaner assembly being disposed upstream of the filter cartridge, a collection system for discharging the separated particulate matter from the collection port, the collection system including an electric motor coupled to a fan, an input sensor that generates an input signal related to a parameter related to one or more of the precleaner assembly, the air cleaner assembly, the power plant that receives air from the air cleaner assembly, and the vehicle associated with the power plant, and a controller that operates the speed of the collection system based on the input signal from the input sensor.

Description

[Technical Field]

[0001] This application was filed as a PCT international application on March 19, 2021, and claims the benefit of priority granted to U.S. Provisional Patent Application No. 62 / 992,834, filed on March 20, 2020, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to a filter device for use in filtering air, typically the intake air of an internal combustion engine, and more particularly to a filter assembly including multiple components arranged within a housing to provide a desired filtering capacity. [Background technology]

[0003] Filtration of air or other gases is desirable in many systems. A typical application is the filtration of intake air to an internal combustion engine. Another application is the filtration of crankcase ventilation filter assemblies. Typically, such systems include a filter assembly having a serviceable filter cartridge therein. After a period of use, the filter media within the filter housing requires service, either by cleaning or complete replacement. Typically, in air cleaners or crankcase ventilation filter assemblies used with, for example, a vehicle's internal combustion engine, the filter media is housed in a removable, replaceable, or serviceable, component commonly referred to as a filter element or cartridge. In some applications, particularly those in which the machine operates in a harsh environment, a precleaner assembly may be utilized to remove larger contaminants from the airflow stream to extend the life of the filter media. Summary of the Invention [Means for solving the problem]

[0004] An air cleaner assembly for filtering the intake air of a power plant includes a filter cartridge disposed within a housing of the air cleaner assembly, a precleaner assembly including at least one particulate separator for separating particulate matter from an air flow stream and a collection port for discharging the separated particulate matter, the precleaner assembly being disposed upstream of the filter cartridge, a collection system for discharging the separated particulate matter from the collection port, the collection system including an electric motor coupled to a fan, an input sensor that generates an input signal related to a parameter related to one or more of the precleaner assembly, the air cleaner assembly, the power plant that receives air from the air cleaner assembly, and the vehicle associated with the power plant, and a controller that operates the speed of the collection system based on the input signal from the input sensor.

[0005] In some examples, the operating parameter is one or more of a sensed dust condition in the air flow stream, a GPS location of the vehicle, a sensed pressure drop in the air flow stream across the precleaner assembly, a dust removal efficiency of the precleaner assembly, and an air flow rate of the air flow stream passing through the precleaner assembly.

[0006] In some instances, the controller commands the collection system to shut down when a threshold value for an operating parameter is exceeded.

[0007] In some examples, the controller receives at least one input for controlling the speed of the collection system, the at least one input signal corresponding to one or more of vehicle speed, engine speed, engine load, operator input, vehicle position, pressure drop across the filter element, mass air flow through the precleaner assembly, presence of moisture or water, vehicle or engine vibration, filter change frequency or number of filter changes, filter identification information, and engine or vehicle identification information.

[0008] A method of operating a collection system for an air cleaner assembly may include providing a filter cartridge within a housing of the air cleaner assembly, providing a precleaner assembly including at least one particulate separator for separating particulate matter from an air flow stream and a collection port for discharging the separated particulate matter, the precleaner assembly being disposed upstream of the filter cartridge, providing a collection system for discharging the separated particulate matter from the collection port, receiving at least one input signal with a controller related to a parameter associated with one or more of the precleaner assembly, the air cleaner assembly, a power plant receiving air from the air cleaner assembly, and a vehicle associated with the power plant, and manipulating a speed of the collection system with the controller based on the at least one input. The method may further include manipulating the speed of the collection system to ensure that pressure across the collection system is at least equal to the pressure in the precleaner.

[0009] In some examples, the input signal parameters are one or more of a sensed dust condition in the air flow stream, a GPS location of the vehicle, a sensed pressure drop in the air flow stream across the precleaner assembly, a dust removal efficiency of the precleaner assembly, and an air flow rate of the air flow stream passing through the precleaner assembly.

[0010] In some examples, the input signal parameters include a vehicle location input, and the controller activates the collection system if the vehicle location input corresponds to a location inside or outside a predetermined geographic region.

[0011] In some examples, the inputs include one or more of a vehicle speed, a vehicle engine speed, and a vehicle engine load input, and the controller activates the collection system when one or more of the vehicle speed, the vehicle engine speed, and the vehicle engine load exceed or fall below a predetermined threshold.

[0012] In some examples, the inputs include inputs corresponding to one or both of the air pressure drop across the precleaner assembly and the filter element, and the controller activates the collection system when the air pressure drop exceeds or falls below a predetermined threshold.

[0013] In some examples, the input includes an input corresponding to one or both of an acoustic input and a vibration input, and the controller activates the collection system when the acoustic input or the vibration input exceeds or falls below a predetermined threshold.

[0014] In some examples, the inputs include inputs corresponding to one or both of a filter element replacement or cleaning frequency and a total number of filter element replacements, and the controller activates the collection system when the replacement or cleaning frequency input or the total number of filter element replacements input exceeds or falls below a predetermined threshold.

[0015] In some examples, the input includes input corresponding to one or more of a filter element identification, an engine identification, and a vehicle identification, and the controller activates the collection system based on the identification of the one or more of the filter element, the engine, and the vehicle.

[0016] In some examples, the inputs include inputs corresponding to one or both of an air flow rate through the precleaner assembly and an air flow rate through the filter element, and the controller activates the collection system when the air flow rate exceeds or falls below a predetermined threshold.

[0017] In some examples, the input includes weather condition parameters identified via data received from a weather forecasting agency, and the controller activates the collection system when the weather condition parameters exceed or fall below a predetermined threshold.

[0018] In some examples, the method further includes sending a speed signal output to the collection system motor, receiving a speed signal input from the collection system motor, and generating an output maintenance signal if a difference between the speed signal input and the speed signal output exceeds a threshold value.

[0019] In some examples, the method further includes operating the collection system at one or both of a minimum operating condition and a high operating condition, and when parameters associated with either the minimum operating condition or the high operating condition are met, the controller overrides the output to the collection fan motor to a different speed.

[0020] An air cleaner assembly for filtering the intake air of a power plant may include: a filter cartridge disposed within a housing of the air cleaner assembly; a precleaner assembly including at least one particulate separator for separating particulate matter from an air flow stream and a collection port for discharging the separated particulate matter, the precleaner assembly being located upstream of the filter cartridge; a collection system for discharging the separated particulate matter from the collection port, the collection system including an electric motor coupled to a fan; and a control system for operating the speed of the electric motor so that a differential pressure across the collection system is at least equal to or exceeds the pressure within the precleaner.

[0021] In some examples, the air cleaner can include a first pressure sensor positioned to sense pressure between the precleaner and the filter cartridge, and the controller receives an input from the first pressure sensor and sends an output signal to the collection system motor based on the input.

[0022] In some examples, the controller determines the pressure in the precleaner based on the sensed pressure at the first pressure sensor.

[0023] In some examples, the controller includes a transfer function for determining the pressure in the precleaner based on the sensed pressure at the first pressure sensor.

[0024] In some examples, the transfer function includes a first correlation between the air mass flow rate through the precleaner and the pressure in the precleaner, and a second correlation between the air mass flow rate through the precleaner and the pressure between the precleaner and the filter cartridge.

[0025] In some examples, the air cleaner further includes a second pressure sensor positioned to sense pressure within the precleaner and provide an input to the controller.

[0026] In some examples, the controller operates the collection system motor at a maximum operating speed when the pressure sensed by the first pressure sensor exceeds a threshold value.

[0027] In some examples, when the pressure sensed by the first pressure sensor exceeds a threshold value, the controller sends an output service signal associated with the precleaner assembly.

[0028] In some examples, the output signal to the collection system motor is a rotational speed control signal.

[0029] In some examples, the rotational speed control signal is a pulse width modulated (PWM) signal.

[0030] In some examples, the control system includes a first map that correlates the PWM signal to the pressure drop across the collection system.

[0031] In some examples, the control system includes one or more pressure mapping curves correlating the collection fan PWM signal, the flow rate through the collection system, and the pressure signal at the first pressure sensor.

[0032] In some examples, the control system includes a transfer function that generates a collection system motor speed output PWM signal from the first pressure sensor input, the transfer function being derived from the first map and one or more pressure mapping curves.

[0033] In some examples, the control system includes a minimum rotational speed setpoint below which the collection system motor will not be operated.

[0034] An air cleaner assembly for filtering the intake air of a power plant includes: a filter cartridge disposed within a housing of the air cleaner assembly; a precleaner assembly including at least one particulate separator for separating particulate matter from an air flow stream and a collection port for discharging the separated particulate matter, the precleaner assembly being located upstream of the filter cartridge; a collection system for discharging the separated particulate matter from the collection port, the collection system including a motor coupled to a fan; and a control system including a controller that sends a speed signal output to the collection system motor and receives a speed signal input from the collection system motor, the controller generating an output maintenance signal when a difference between the speed signal input and the speed signal output exceeds a threshold value.

[0035] In some examples, the controller operates the collection system motor speed as a function of input signals related to one or more operating parameters associated with the precleaner assembly, the air cleaner assembly, the power plant receiving air from the air cleaner assembly, and / or the vehicle associated with the power plant.

[0036] The air cleaner may include: a filter cartridge disposed within the housing of the air cleaner assembly; a precleaner assembly including at least one particulate separator for separating particulate matter from the air flow stream and a collection port for discharging the separated particulate matter, the precleaner assembly disposed upstream of the filter cartridge; a collection system for discharging the separated particulate matter from the collection port, the collection system including a motor coupled to a fan; and a controller that varies the speed of the collection system motor in a normal operating mode, the speed being a function of input signals related to one or more operating parameters related to the precleaner assembly, the air cleaner assembly, a power plant receiving air from the air cleaner assembly, and / or a vehicle associated with the power plant, the controller including one or both of a minimum operating state and a high operating state, and the controller overrides the output to the collection fan motor to a different speed when parameters related to either the minimum and high operating states are met.

[0037] In some examples, the minimum operating condition includes a parameter related to a minimum pressure in the precleaner.

[0038] In some examples, the minimum operating condition includes a parameter related to a minimum rotational speed setting for the collection fan motor.

[0039] In some examples, the high operating condition includes a parameter related to the maximum pressure in the precleaner.

[0040] The present invention will be further described with reference to the accompanying drawings, in which like structure is referenced by like numerals throughout the several views. [Brief explanation of the drawings]

[0041] [Figure 1] 1 is a schematic diagram of a system including an air cleaner assembly, a collection system, and a control system having features according to the present disclosure. [Figure 2]2 is a schematic perspective view of an exemplary air cleaner assembly that can be used in the system shown in FIG. 1. [Figure 3] FIG. 3 is a schematic cross-sectional view of the air cleaner assembly shown in FIG. 2. [Figure 4] FIG. 2 is a diagram illustrating a control process of the control system shown in FIG. [Figure 5] FIG. 5 is a diagram illustrating a normal operating state of the control process shown in FIG. 4. [Figure 6] FIG. 6 is a diagram illustrating an example of a normal operating state illustrated in FIG. 5. [Figure 7] FIG. 6 is a diagram illustrating an example of a normal operating state illustrated in FIG. 5. [Figure 8] FIG. 5 illustrates an exemplary minimum operating state of the control process shown in FIG. 4. [Figure 9] FIG. 5 illustrates an exemplary minimum operating state of the control process shown in FIG. 4. [Figure 10] FIG. 5 illustrates an exemplary high operating state of the control process shown in FIG. 4. [Figure 11] 5 illustrates an exemplary monitoring process that can be used in the control process shown in FIG. 4 and the control system shown in FIG. 1. [Figure 12] 5 illustrates an exemplary monitoring process that can be used in the control process shown in FIG. 4 and the control system shown in FIG. 1. [Figure 13] 4 is a schematic graphical representation of separator efficiency versus engine flow rate for the air cleaner assembly shown in FIGS. 1-3 compared to a prior art system. [Figure 14] FIG. 14 is a graph illustrating performance testing of the air cleaner assembly and collection system shown in FIG. 13. [Figure 15] FIG. 4 is a graph illustrating an exemplary relationship between operating time and engine volumetric flow rate. [Figure 16] 16 is a graphical representation illustrating an example relationship between filter mass gain and engine volumetric flow rate based on the operating conditions depicted in FIG. 15. DETAILED DESCRIPTION OF THE INVENTION

[0042] Exemplary filter assemblies, filter cartridges, and their features and components are described and illustrated herein. Various specific features and components are characterized in detail. Many may be applied to provide advantages. However, there is no specific requirement that the various individual features and components be applied to an overall assembly having all of the described features and characteristics in order to provide some advantage consistent with this disclosure.

[0043] 1, a system including an air cleaner assembly 100, a collection system 450, and a control system 500 is generally presented. As depicted, the air cleaner assembly 100 includes a precleaner 400 and filter cartridges 200, 300, which in turn remove particulate matter from an air stream 14 so that clean air can be delivered to an air consuming device 12, such as an internal combustion engine or compressor. The collection system 450 operates to remove the separated particulate matter from the air cleaner assembly 100. The air cleaner assembly 100, the collection system 450, and the control system 500 are described in further detail in the following paragraphs.

[0044] 2 and 3, an air cleaner assembly 100 is presented. In one aspect, the air cleaner assembly 100 includes a housing 102 defining an interior cavity 104. The housing 102 may be configured as a main housing 106 and a cover 108 that allows access to the interior cavity 104 when the cover 108 is removed from the housing 106. The cover 108 may be secured to the housing 108 using any number of methods or approaches known in the art, such as by over-center latches, interacting lugs, etc. In one aspect, the housing 102 includes an inlet 110 for receiving raw, untreated air and an outlet 112 for discharging clean, filtered air.

[0045] 3, first filter cartridge 200, second filter cartridge 300, and precleaner assembly 400 are shown within interior cavity 104 of housing 102. Collectively, these components convert unfiltered air received at inlet 110 into clean, filtered air that is delivered to outlet 112.

[0046] In one aspect, the first filter cartridge 200 is generally positionable between the precleaner assembly 400 and the second filter cartridge 300. In a typical arrangement, the first filter cartridge 200 is removably positioned within the air cleaner assembly internal cavity 104 and would typically be considered a removable and replaceable service part as desired and / or needed. In one aspect, the first filter cartridge 200 includes a media pack 202 having an inlet flow face 204 for receiving pre-cleaned air from the precleaner assembly 400 and an outlet flow face 206 for delivering filtered air. In the example shown, the media pack 202 has an obround or racetrack cross-sectional shape. However, other shapes are possible, such as circular, oval, and rectangular cross-sectional shapes. In one aspect, the media pack 202 defines a periphery 208 extending between the inlet and outlet flow faces 204, 206. In the illustrated example, the media pack 202 is formed from a coiled media structure, e.g., a media structure having a fluted (typically corrugated) media sheet and a facing media sheet that together define parallel grooves to form a fluted or Z-filter media structure. Suitable media structures for the media pack 202 are discussed in more detail in the "Media Types and Configurations" section. In one aspect, the filter cartridge 200 includes a seal member 210 that forms a seal against the interior surface of the housing 102 so that all air passing through the interior cavity must pass through the media pack 202.

[0047] In one embodiment, the second filter cartridge 300 is generally positionable between the outlet 112 and the first filter cartridge 200. In a typical arrangement, the second filter cartridge 300 is removably positioned within the internal cavity 104 of the air cleaner assembly and would typically be considered a removable and replaceable service part as desired and / or needed. In one embodiment, the second filter cartridge 300 includes a media pack 302 having an inlet flow face 304 for receiving air from the first filter cartridge 200 and an outlet flow face 306 for delivering filtered air to the outlet 112. In the example shown, the media pack 302 has an obround or racetrack cross-sectional shape. However, other shapes are possible, such as circular, oval, and rectangular cross-sectional shapes. In one embodiment, the media pack 302 defines a periphery 308 extending between the inlet and outlet flow faces 304, 306. In the example shown, the media pack 302 is formed from pleated media. Suitable media configurations for the media pack 302 are discussed in more detail in the "Media Types and Configurations" section. In one embodiment, the filter cartridge 300 includes a seal member 310 that forms a seal against the interior surface of the housing 302 so that all air passing through the interior cavity must pass through the media pack 302.

[0048] 2 and 3, precleaner assembly 400 is shown as being a two-stage air cleaner assembly and includes a plurality of separator tube arrangements 402. Precleaner assembly 400 can be used to pre-clean selected materials (contaminants) carried by the air stream to air cleaner assembly 100 before the air reaches first filter cartridge 200 positioned therein. Such pre-cleaning generally results in substantial removal of liquid particulates, such as rainwater or splash water, and / or various (particularly large) dust or other particles. In the illustrated example, contaminants removed by precleaner assembly 400 can be discharged from internal cavity 104 via exhaust port 114 extending through housing 102. In some embodiments, precleaner assembly 400 forms part of access cover 108.

[0049] In the example shown, the precleaner assembly 400 includes two shell or cover components secured together: an outer (inlet) cover portion 404 and an inner (outlet tube) cover portion 406. In some applications featured herein, the components 404, 406 are snap-fit ​​or otherwise secured together but are configured to be separable for ease of cleaning. However, in some applications of the technology featured herein, the two cover or shell components 404, 406 may be secured together during assembly and not reseparable.

[0050] As previously mentioned, the precleaner assembly 400 may include multiple separator tube arrangements 402. As most readily seen in FIG. 3 , each of the separator tube arrangements 402 may include an inlet end 402a and an outlet end 402b. Proximate the inlet end 402a, each of the separator tube arrangements 402 includes a vane arrangement 402c disposed within an inlet flow tube 402d extending in a direction toward the outlet end 402b. As shown, the vane arrangement 402c and the inlet flow tube 402d are integrally formed within the outer cover 404. However, these components may alternatively be provided separately and later attached to the outer cover 404, for example, by a press fit. In the example shown, the inlet inner cover 406 includes multiple outlet flow tubes 402e protruding from a tube sheet 402f. Each of the outlet flow tubes 402e projects toward the inlet end 402a and partially receives the inlet flow tube 402d, with an annulus or gap 402g existing between the inlet and outlet flow tubes 402d.

[0051] The general operation of the precleaner assembly 400 is to separate material (contaminants) as it enters the air cleaner assembly 100, allowing it to exit through the outlet port 114 of the housing 102. This prevents certain materials from ever reaching the filter cartridge component (e.g., filter cartridges 100, 200) housed therein. Generally, each tube 402 operates with an internally implemented centrifugal separation of contaminants. To accomplish this, air entering the inlet end 402a is generally directed into a cyclone pattern by the vanes of the vane arrangement 402c. This action forces contaminants against the inlet flow tube 402d, forcing them into the larger interior volume 412 of the precleaner 400 before ultimately exiting through the port 114. Because the inlet end of the outlet flow tube 402e is located within the outlet end of the inlet flow tube 402c, contaminants that can be separated and forced against the interior wall of the inlet flow tube 402c cannot enter the outlet flow tube 402e. Tube sheet 402f blocks air flow between inner cover 406 and the downstream portion of air cleaner assembly 100, so that all air separated by air separator tube 402 must be directed through outlet flow tube 402e. An exemplary separator tube arrangement usable in the systems disclosed herein is shown and described in PCT International Patent Application Publication No. WO 2016 / 105560, filed December 23, 2015, and incorporated herein by reference in its entirety. Alternative arrangements exist. Other types of precleaners can be used without departing from the concepts herein. For example, a single-vane precleaner of the type disclosed in U.S. Patent Application Serial No. 62 / 673,583, filed May 18, 2018, and entitled "PRECLEANER ARRANGEMENT FOR USE IN AIR FILTRATION METHODS," may be used.

[0052] 1 , a collection system 450 may be provided that is connected directly or indirectly, such as via a duct or adapter, to collection port 114. Some operating environments trap low-density particulate matter within precleaner interior volume 412 that cannot be easily removed through exhaust port 114 by gravity alone. In the example shown, collection system 450 is configured as a collection pump 450 and includes a fan or fans 452 driven by a motor 454, e.g., an electric motor 454. Thus, when it is desired to evacuate interior volume 412, or at least ensure that interior volume 412 is evacuated, control system 500, described below, can operate motor 454 to create a vacuum to draw and discharge particulate matter from interior volume 412. Because collection system 450 includes an independent motor 454, collection system 450 may be operated independently of the operation of power plant 12 and the vehicle 10 on which power plant 12 may be mounted. Thus, the activation and rate control collection system 450 can be controlled to meet a variety of parameters that are not possible using typical collection systems.

[0053] Referring to FIG. 13 , a graphical representation 900 is provided comparing an air cleaner 100 with a prior art trap system (line 902) and an air cleaner 100 with a trap system 450 of the present disclosure (line 904), where separator efficiency, expressed as a percentage, is plotted against volumetric engine flow, expressed in unitless, scaled form. In general, trap systems are typically designed so that the trapped flow is equal to a fixed percentage of the engine flow. Such a configuration can be referred to as a combined system because there is a fixed relationship between engine flow and trapped flow. Line 902 represents a combined system with a trapped flow equal to 10% of the engine flow, and it can be seen that the separator efficiency is less than 86% at relatively low engine flow rates and peaks at approximately 93% at maximum engine flow rates, resulting in a time-averaged separator efficiency of approximately 88.3%.

[0054] In contrast to a combined system, the flow rate of the collection system 450 can be controlled independently of the engine flow rate. For example, the collection system 450 can be controlled to have a relatively high flow rate at low and intermediate engine flow rates compared to a combined system to increase separator efficiency. Such a configuration is sometimes referred to as a non-coupled system. Line 904 represents a non-coupled system in which the flow rate of the collection system 450 is calculated as a non-fixed function of engine flow rate. With such an approach, as shown in FIG. 13 as line 904, it can be seen that the separator efficiency increases to approximately 89% at relatively low engine flow rates and peaks at over 94% at maximum engine flow rates, with a time-averaged separator efficiency of approximately 91.4%, representing a 3.1% increase in the time-averaged separator efficiency of the disclosed non-coupled system. Therefore, the advantages of a non-coupled system over a typical combined system can be expressed as an increase in minimum separator efficiency, an increase in maximum separator efficiency, and an increase in time-averaged separator efficiency.

[0055] Referring to FIG. 14 , a graphical representation is provided illustrating actual test results for air cleaner 100 in various configurations with and without trapping system 450. This graphical representation shows a comparison of trapping pressure (Y-axis) compared to flow rate through air cleaner 100. Generally, higher trapping pressure is beneficial for more effectively removing separated particulate matter from the precleaner. As shown, lines 912-918 represent test results for air cleaner 100 that does not use trapping system 450 and instead relies on a prior art trapping suction pressure that increases at a constant rate relative to airflow through air cleaner 100. Tests 912-918 were conducted at a bound or fixed percent trapping, with the trapping level increasing progressively through tests 912-914. For each of these tests, the trapping pressure was observed to be near zero at low flow rates, thereby indicating little or no effective trapping at these flow rates. Referring to lines 920-924, the scavenging system 450 is connected to the air cleaner 100 and operated at a first speed (920), a second speed (922) higher than the first speed, and a third speed (924) higher than the second speed. As can be readily seen in FIG. 14 , the scavenging pressures at each of the test speeds with the scavenging pump 450 result in significantly higher scavenging pressures at lower system flow rates compared to tests without the scavenging pump 450. These scavenging pressure benefits are realized throughout the entire operating system flow rate. As previously mentioned, the scavenging pump 450 is controllable independently of the primary air flow through the air cleaner 100 caused by the power plant 12, and is therefore capable of providing higher levels of scavenging flow at lower air cleaner flow rates than is possible with prior art systems.

[0056] Because increased separator efficiency translates into reduced filter loading, a further benefit of a non-coupled system over a combined system can also be expressed as increased filter life. This benefit is illustrated in graph 940 shown in FIG. 16, which illustrates actual test results for combined system 942 and non-coupled system 944 under the operating conditions shown in FIG. 15. Graph 940 shows that the filter mass gain for non-coupled system 944 is less than the filter mass gain for combined system 922 at all engine volumetric flow rates, with the greatest improvement occurring at intermediate operating flow conditions. As a result, the test depicted in FIG. 16 shows a 26.3% reduction in filter loading for non-coupled system 944 using collection system 450 compared to a standard combined system with collection flow set at 10% of engine flow.

[0057] Typically, coupled trap systems are driven by the exhaust flow, and therefore have a maximum trap flow rate for a given engine condition. In contrast, uncoupled trap systems are free to operate at any condition based on inputs provided, providing flexibility to provide optimized system performance, such as filter life, pressure drop, energy consumption, etc. These inputs range from GPS location information to various weather-related sensors to determine optimal performance for uncoupled trap systems, and are described in more detail in later sections.

[0058] Controller 500 and Operation Modes Continuing with reference to FIG. 1 , electronic controller 500 is shown generally as including a processor 500A and a non-transitory storage medium or memory 500B, such as RAM, a flash drive, or a hard drive. Memory 500B is for storing executable code, operating parameters, and inputs from an operator user interface 502 while processor 500A executes the code. Memory 500B may also be for storing reference information 500D, such as maps and / or look-up tables. Electronic controller is also shown as including a transmit / receive port 500C, such as an Ethernet port, for bidirectional communication with a WAN / LAN associated with the automation system. User interface 502 may be provided for starting and stopping the system, allowing a user to manipulate certain settings or inputs to controller 500, and view information regarding system operation.

[0059] The electronic controller 500 typically includes at least some form of memory 500B. Examples of memory 500B include computer-readable media. Computer-readable media include any available media that can be accessed by the processor 500A. By way of example, computer-readable media include computer-readable storage media and computer-readable communication media.

[0060] Computer-readable storage media include volatile and nonvolatile, removable and non-removable media embodied in any device configured to store information such as computer-readable instructions, data structures, program modules, or other data, including, but not limited to, random access memory, read-only memory, electrically erasable programmable read-only memory, flash memory or other memory technology, compact disk read-only memory, digital versatile disk or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and that can be accessed by processor 500A.

[0061] Computer-readable communication media typically embodied computer-readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and include any information delivery media. The term "modulated data signal" means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. By way of example, computer-readable communication media includes wired media such as a wired network or direct-wired connection, and wireless media such as acoustic, radio frequency, infrared and other wireless media. Combinations of any of the above are also included within the scope of computer-readable media.

[0062] The electronic controller 500 is also shown as having a number of inputs / outputs that may be used to operate the collection system 450. For example, as previously described, the motor 454 may receive an output 504 from the controller 500. An example of an input 506 that may be received by the controller 500 is a parameter 506a. The parameter 506a may relate to the vehicle 10, the power plant 12, the air cleaner 100, the precleaner 400, or something else. Examples of parameters 506a are vehicle speed, engine speed, engine or vehicle operating hours, engine mass flow rate, operator interface signals, vehicle position (e.g., GPS position input via an integrated GPS unit or via a vehicle GPS unit), differential pressure signal (e.g., across the filter cartridge 100), water presence signal, vehicle, engine, or air cleaner assembly vibration signal 506 (e.g., accelerometer input), filter cartridge change or cleaning frequency, filter cartridge identification information, engine identification information, air flow rate, sound level via an acoustic sensor (used as a proxy for vibration), and / or air quality input via a particulate matter sensor (e.g., a laser real-time optical particle counter). The controller 500 may also include additional inputs and outputs for the desired operation of the collection system and associated systems. 1 and 3, the controller 500 may include a first pressure sensor P1 related to the pressure in the precleaner, a second pressure sensor P2 located between the precleaner and the main filter element 200, a third pressure sensor P3 located between the main filter element 200 and the safety filter element 300, and a fourth pressure sensor P4 located downstream of the safety filter element 300. The controller 500 may also include an input signal from the collection fan motor 454, e.g., a speed input signal indicative of the actual rotational speed of the motor 454 and the fan 452. Additional input sensors related to weather data may also be included, e.g., a temperature sensor, a humidity sensor, a barometric pressure sensor, a moisture or rain sensor, a wind direction and speed sensor, a cloud sensor, and / or a solar radiation sensor, in communication with the controller 500.In some examples, electronic controller 500 is a separate controller that receives power from power source 20 and communicates with vehicle controller 22, for example, via the vehicle or CANBUS network. In such cases, additional vehicle information beyond that already discussed may be utilized by the controller, for example, vehicle fuel economy may be used as an input to the controller. In some examples, a vehicle control system functions as electronic controller 500.

[0063] Referring to FIG. 4 , an exemplary operating configuration 1000 is shown in which the collection fan motor 454 is controlled in a normal operating state, and the speed of the collection fan motor 454 is changed or overridden for conditions associated with minimum operating state control or conditions associated with high operating state control. Thus, and in generalized terms, the collection system can be activated in step 1002, and the collection fan motor can be operated in a normal operating mode in 1004. As described further below, the normal operating mode can be any control approach based on one or more selected parameters. In steps 1006 and 1006, the system monitors for minimum and high operating conditions, respectively. In step 1010, when conditions associated with a minimum operating state are met, the collection motor speed is controlled to the higher of those associated with the minimum and normal operating modes. Similarly, in step 1012, when conditions associated with a high operating state are met, the collection motor speed is controlled to the higher of those associated with the high and normal operating modes. Such an approach provides enhanced control of the collection system 450 by providing minimum and high boundaries for normal operating conditions that can be applied when certain conditions apply.

[0064] Referring to FIG. 5, a generalized process 1100 is shown in which a normal operating mode includes monitoring system parameters at 1102, determining setpoints associated with the parameters at 1104, and sending control signals to the trap fan motor 454 to meet the setpoints. In one example of a normal operating mode, the speed of the motor 454 is controlled to achieve a trapped airflow rate that is a function of engine flow rate, as generally shown in FIG. 6 along with process 1200. In a normal operating state 1300, the engine airflow rate is determined at 1202, the fan speed required to achieve a target trapped airflow rate is calculated at 1204, and a control signal to the trap fan motor is sent at 1206. The performance enhancements of the non-coupled system 450 shown in FIGS. 13 and 16 are based on this approach. In one example, the trapped airflow rate can be calculated as the engine flow rate multiplied by a first constant coefficient a and added by a second coefficient b, and can be expressed as: trapped airflow rate = a × (engine flow rate) + b. In one aspect, the first and second constant coefficients a, b may be derived from operational data and / or characteristics associated with the engine 12 and / or the operating environment. Other algorithmic approaches are possible without departing from the concepts presented herein. In one example, the operational data includes data relating engine volumetric flow to engine operating time, as shown in graph 1100 in FIG. 8. In some examples, the operating parameters of the engine 12 may be derived from an established map or lookup table 500D or from real-time operating data.

[0065] In one example of a normal operating configuration, motor 454 is controlled via an input (e.g., input 506d) related to the location of the vehicle or machine. The location input can provide an indication as to the environment in which the vehicle or machine may be located. For example, a location input corresponding to an on-road (e.g., highway) location would provide an indication that the intake air is relatively clean, while a location input corresponding to an off-road location would provide an indication that the intake air is relatively full of pollutants. Similarly, some geographic regions or areas may be associated with air that is relatively high in pollutants compared to other geographic regions or areas. Thus, if a location input indicating a relatively clean environment is provided, the control system may deactivate collection system 454 or operate collection system 454 at a relatively slower speed. Similarly, if a location input indicating a relatively dirty environment is provided, the control system may activate collection system 454 and / or operate collection system 454 at a relatively higher speed. In one example, the location input can be used in combination with the date input to identify times when the climate in a particular region may be associated with higher pollutant levels (e.g., potentially high pollutant conditions can be identified by correlating a particular geographic region to a particular day or month of the year (e.g., to identify high pollen conditions)).

[0066] Many other implementations and general operating control configurations are possible. For example, a vehicle speed (e.g., mph via GPS) input, or an engine speed or load input, can be used to infer whether pollutant conditions are relatively high or low. For example, the capture system 450 may operate at a higher speed as the vehicle speed increases. In one example, the engine speed or load input is used to command the motor 454 to stop or slow down to reduce parasitic losses when the engine is at a high load and / or high speed. In one example, a differential pressure input can infer the current operating state of the precleaner, filter cartridge 100, and / or filter cartridge 200, whereby the motor 454 can be commanded to start and / or speed up to sweep the precleaner. Additionally, the system can monitor the rate of change of pressure drop across the filter to identify conditions for similarly modifying capture system operation. In one example, if the precleaner functions as a water separator, a moisture or water presence sensor input can be used. In such cases, moisture sensor inputs can be used to set the trap flow such that the flow through the separator is optimized for moisture removal. In one example, air mass flow inputs can be used to modify the trap flow when air flow rates are high and to extend the operating window by reducing the precleaner's restriction contribution toward end-of-life. In one example, air flow can be correlated to the pressure drop or restriction through the air cleaner, so that the restriction can be normalized with respect to flow to determine a system loss coefficient, which can then be monitored with respect to the rate of change to infer the pollutant load entering the filter and used to adjust the precleaner bypass flow amount (e.g., a lower rate of change equates to allowing more bypass). In one example, vibration or accelerometer inputs can be used to infer the operating state of the machine or vehicle (e.g., high vibration correlates to off-road use and environment, while low vibration correlates to on-road use and environment, and the operation of the trap system 450 can be controlled accordingly). Similarly, acoustic sensor inputs can be used to estimate vibration for the same purpose.The controller 500 can also monitor the number of filter cartridge 100 installation and removal cycles via an input sensor and modify the operation of the collection system 450 accordingly. The identification of the filter cartridge 100 via the input can also be used to determine the type of filter cartridge installed and, therefore, modify the operation of the collection system 450 accordingly. In one example, the input can be an RFID tag on the filter element that is read by the controller 500. The system can also have an input for an air quality sensor that measures airborne particulate matter levels so that pre-purification can be initiated when high levels of particulate matter are measured and bypass operation can be initiated when airborne particulate matter levels are low. The air quality sensor can be used, for example, to determine when the combine is operating during harvesting or non-harvesting operations and, accordingly, to activate and operate the collection system 450 only when harvesting operations are occurring. During non-harvesting operations, the collection system 450 can be operated at a slower speed or shut off. An operator input to the system 500 or an input from the harvester itself indicating harvesting operations can also provide an indication that the combine is harvesting.

[0067] In some operating configurations, the speed of the collection system 450 can be controlled in an incremental or stepwise manner. In one example, the motor 454 can have multiple discrete settings (e.g., "dirty," "mix," and "clean" settings) that are set directly by the operator. The above inputs can also be compared to predetermined thresholds set within the controller 500 to select between a number of levels (e.g., "dirty," "mix," and "clean" settings) to set the speed and activation of the collection system 450. In one example, and using an approach similar to Equation 1, the speed of the motor 454 can be calculated based on a formula using the above inputs (e.g., motor speed % = a * vehicle speed - b). Air cleaner usage characteristics can also be used to determine the motor speed and trigger level. For example, precleaner efficiency can be plotted against motor speed or other parameters. Incremental speed control can also be used to "tune" the entire system. For example, a given on-road truck model may have four different engine options and may be considered a light-duty truck or a heavy-duty (vocational) truck. While these trucks may all use the same air cleaner, it is expected that performance will be lower in more severe applications than under lighter loads or in less severe environments. An adjustable collection system can smooth out performance differences and influence the air cleaner design from the start. In such cases, engine identification input can be used to determine this. In some examples, the speed of the motor 454 is fully controllable, such that any motor speed between zero and maximum speed can be set by the controller 500.

[0068] Referring to FIG. 7 , an exemplary normal operating state 1300 is presented in which the pressure in the precleaner is used as a reference for the collection fan speed. In the normal operating state 1300, the pressure in the precleaner is determined at 1302, a fan speed setpoint is calculated at 1304, and an output control signal is sent to the collection fan motor at 1306 to meet the fan speed setpoint. In some examples, the fan speed setpoint is calculated based on ensuring that the collection fan generates a differential pressure across the fan that equals or exceeds the pressure in the precleaner. With such an approach, the collection fan ensures that air cannot undesirably flow backward through the collection port. In some examples, the commanded fan speed includes an additional margin or increment beyond the calculated speed required to generate a pressure differential equal to the pressure in the precleaner. For example, the fan speed setpoint may be set to always be 20% higher than the calculated fan speed. In some examples, the pressure in the precleaner is measured directly, such as directly from sensor P1. The pressure within the precleaner can also be calculated from a sensor P2 located between the precleaner and the main filter element 202. The location of pressure sensor P2 has been found to be advantageous in that the pressure at this location is relatively unaffected by the operation of the scavenging fan, whereas the pressure within precleaner P1 is necessarily affected by the scavenging fan.

[0069] In one example, the pressure in the precleaner is calculated from the pressure at P2 by creating an air cleaner-specific topographical map or maps (i.e., a Qmain-P1 map and a Qmain-P2 map) that correlate airflow rates through the air cleaner Qmain to the corresponding pressures at P1 and P2. In one particular example, such maps can be created by testing the air cleaner with a closed collection tube to determine P1 and P2 and various airflow rates, thereby creating a map from which P1 can be determined from readings at P2. Additional maps can also be empirically derived that establish the pressure at P1 and / or P2 at various different flow rates through the air cleaner (Qmain) and collection port (Qcollection). In some examples, a map or lookup table can be created that correlates P1 and P2 based on the determined correlation. In some examples, additional maps and / or calculations can be used to correlate the pressure drop (dP) and / or flow (Qcollection) across the collection fan with the output signal to the fan motor, such as a pulse-width modulated (PWM) signal to the motor. In such cases, a PWM-dP map or lookup table can be created. Other implementations are possible where the output signal is not a PWM signal. For example, the output signal could be a voltage output, a current loop output, a frequency output, a digital output, among others. In such cases, a map or lookup table can be created that associates dP with the particular output signal used. In some examples, the above map or a similar map can be used to derive a transfer function such that the output signal to the collection motor can be calculated directly from the P2 input signal. In one example, a transfer function using a PWM output signal for fan speed can be defined as follows: F speed=f(P2), in the formula, F-Speed: Desired fan speed (RPM) P2: Pressure after the precleaner and before the main element (Pa)

[0070] If the transfer function is provided as a simple linear function, the F speed can be calculated as follows: F speed=10×P2×5000

[0071] In other implementations, a lookup table can be used to determine the speed of the PWM output signal based on P2. In either approach, the relationship between PWM and RPM is fan dependent, so using the RPM setting can be advantageous in some embodiments.

[0072] With reference to Figures 8 and 9, minimum operating conditions are presented that may be used to override the calculated or determined capture fan speed under normal operating mode. Figure 8 shows state 1400, where a minimum capture fan speed limit, such as a minimum RPM, is established at 1402, and the fan speed is controlled to the minimum RPM at 1404 if the normal operating mode capture flow is below the minimum RPM. Such an example may occur when a signal from a sensor (e.g., P2) used to calculate the normal operating mode capture fan speed is interrupted or otherwise unavailable. Figure 9 shows state 1500 in which the capture fan minimum speed is determined as a function of maintaining a differential pressure across the fan above the precleaner pressure, with steps 1502-1508 generally similar to those described with reference to Figure 7. The approach of Figure 9 may be used when the capture fan speed under normal operating conditions is based on another parameter, such as a calculated percentage of engine flow.

[0073] 10 illustrates a high operating condition 1600 in which an input from a first pressure sensor, such as P2, is monitored at 1602, the input is compared to a threshold, such as a normal maximum pressure value, at 1604, and if the pressure exceeds the threshold an override output is sent to the collection fan motor at 1606. Examples of such conditions may occur if the precleaner is clogged or the air flow through the air cleaner is too high. A collection fan service signal may be generated at 1608 under such circumstances.

[0074] 11 and 12 illustrate monitoring processes 1700, 1800 that can generate an additional service signal if a potential fault is detected. In process 1700, a signal indicating the actual fan speed is received from the collection fan motor at 1702 by the controller. At 1704, the speed signal is compared to the motor's commanded speed. If the actual fan speed is within a specified range (e.g., ±10%) of the commanded speed, the collection fan can be evaluated as operating satisfactorily. In such a case, a signal that the fan is operating properly can be generated at 1706. If the collection fan's actual speed falls outside the range, a service signal can be generated at 1706. In an alternative approach, for example, if the output to the collection fan is not a speed command signal, the controller can use the command signal to calculate a fan speed to compare with the actual fan speed signal. The system can also be configured to determine the fan motor's power consumption required to reach a particular speed and compare it to corresponding values ​​for healthy, new, and / or unworn fan conditions. If the power consumption for a given speed is outside of an acceptable range (i.e., a particular threshold and / or range), a service signal can be generated. Typically, the collection fan speed increases over time to maintain the same airflow or pressure drop as debris exhausted by the collection fan erodes the fan blades over time. These approaches therefore provide a valuable diagnostic tool for identifying when a collection fan may be nearing the end of its useful life before it fails, so that maintenance can be performed in a timely manner without excessive downtime. In some examples, the collection fan is configured to be a relatively inexpensive service part that can be easily removed and replaced as desired and / or needed. In some examples, the collection fan is configured as a more integral part of the air cleaner and is configured in a more robust manner, with the intention that the fan will have a longer useful life that can be maintained through maintenance efforts.

[0075] 12 shows steps 1802-1806 whereby the pressure in the precleaner is compared to a threshold value, for example, a threshold value corresponding to the maximum expected pressure in the precleaner under normal operating conditions. If the pressure in the precleaner is below the threshold value, a signal can be generated that operation of the precleaner is acceptable. If the pressure in the precleaner is above the threshold value, a signal can be generated that the precleaner needs to be serviced.

[0076] In some examples, the controller 500 and / or vehicle control systems communicating with the controller 500 may be configured with a wireless receiver / transmitter 500C to enable remote communication between the controller 500 and other systems. Such a configuration may allow the controller 500 to be adapted to receive additional information or data for controlling the collection system 450. In one example, the controller 500 may receive real-time and forecasted weather data APIs via the cloud 600 and then be configured to operate the collection system 450 during weather and atmospheric conditions corresponding to high particulate matter or low air quality conditions (e.g., low pollen, dust, etc.). However, as previously related, atmospheric or weather conditions may also be assessed from local sensors mounted on the vehicle. For example, atmospheric or weather conditions may be determined via inputs from temperature sensors, humidity sensors, barometric pressure sensors, moisture or rain sensors, wind direction and speed sensors, cloud sensors, and / or solar radiation sensors in communication with the controller 500. In some examples, locally received atmospheric and weather data (via sensors) and remotely received atmospheric and weather data can be used by controller 500 to control collection system 450.

[0077] In one aspect, the wireless receiver / transmitter 500C may also be in communication with a remote system 700 (e.g., a server 700A and a database 700B), which may be configured to perform some or all of the aforementioned logical functions previously attributed to the controller 500. The controller 500 may also transmit current or recorded operational data to the remote system 700 for archiving. The controller 500 and remote system 700 may also be configured to enable control algorithms stored in the controller 500 to be implemented and / or updated via the remote server 700. In one example, the remote system 700 may be arranged to communicate with multiple controllers 500 so that the performance of multiple systems can be monitored and evaluated simultaneously. The remote system 700 may use individual or aggregated controller data to optimize the control algorithms and / or operational setpoints used by the controllers 500. In one exemplary implementation, a fleet operator may develop operational strategies that are pushed out to the controllers 500 of all vehicles in the fleet via the remote system 700. One exemplary policy is to set collection system 450 to a default mode or setting for all vehicles until the bypass mode is overridden. The policy can include instructions for the controller to override the default mode under certain conditions (e.g., as described above) and / or can include remote overrides that allow the fleet operator to selectively place collection systems in different modes based on identification of certain conditions (e.g., a predicted dust storm, a change to a dustier environment in which the fleet's vehicles are used, etc.). Remote system 700 can also be configured to provide the fleet owner with the current operating status of each collection system associated with a vehicle and to provide the fleet owner with the ability to directly override the commanded position of collection system 450 by controller 500.

[0078] Media type and composition Any type of filter media can be used as the media pack of the filter cartridges 100, 200 according to embodiments of the present invention. For example, woven and nonwoven materials using natural and / or synthetic fibers can be used to form fluted, pleated, and depth media. Exemplary configurations include fluted filter media, such as z-filter structures. As used herein, the term "z-filter structure" refers to a type of filter structure in which individual corrugated, folded, or otherwise formed filter grooves are used to define sets of longitudinal, typically parallel, inlet and outlet filter grooves for fluid flow through the media, with fluid flowing along the length of the grooves between opposite inlet and outlet flow ends (or flow faces) of the media. Some examples of filter media are described in U.S. Patent Nos. 5,820,646; 5,772,883; 5,902,364; 5,792,247; 5,895,574; 6,210,469; 6,190,432; 6,350,296; 6,179,890; 6,235,195; D399,944; D428,128; D396,098; D398,046; and D437,401, each of which is incorporated herein by reference.

[0079] One type of z-filter media utilizes two specific media components bonded together to form the media structure. The two components include a fluted (typically corrugated) media sheet and a facing media sheet. The facing media sheet is typically non-corrugated, but can also be corrugated (e.g., perpendicular to the groove direction), as described in U.S. Provisional Patent Application No. 60 / 543,804, filed February 11, 2004, and published August 25, 2005, as WO 05 / 077487, which is incorporated herein by reference.

[0080] The fluted media sheet and the facing media sheet are used together to define a media having parallel inlet and outlet grooves. In some examples, the fluted sheet and the facing sheet are secured together and then rolled into a media strip to form a z-filter media structure. Such an arrangement is described, for example, in U.S. Patent Nos. 6,235,195 and 6,179,890, each of which is incorporated herein by reference.

[0081] In certain other arrangements, several non-coiled sections or strips of fluted (typically corrugated) media secured to opposing media are stacked together to form the filter structure.

[0082] Corrugated media is a specific form of grooved media, which has individual grooves or ridges (e.g., formed by corrugating or folding) extending therethrough. The term "corrugation" is used herein to refer to a structure in a media, such as media having a groove structure obtained by passing the media between two corrugating rollers (e.g., through a nip or bite between two rollers, each of which has surface features suitable for causing corrugations in the resulting media).

[0083] A serviceable filter element or cartridge configuration utilizing z-filter media is sometimes referred to as a "straight-through flow configuration" or variations thereof. Generally, a serviceable filter element or cartridge has an inlet flow end (or face) and an opposite outlet flow end (or face), with flow entering and exiting the filter cartridge generally in the same straight-through direction. The term "serviceable" in this context is meant to refer to a media-containing filter cartridge that is periodically removed and replaced from a corresponding fluid (e.g., air) cleaner.

[0084] It should be noted that multiple embodiments are depicted and described. These embodiments are not intended to be exclusive with respect to the depicted features. That is, selected features of one embodiment can be advantageously applied to one or more of the other embodiments, if desired. In many examples, the depicted filter assembly is an air cleaner assembly used, for example, to filter the intake air of an internal combustion engine. Additional applications are possible, such as applications in which the filter assembly is a crankcase ventilation filter assembly, in which the filter cartridge is used to filter crankcase blow-by gases, which typically contain both particulate and liquid contaminants therein. Both types of filter assemblies are generally referred to as "gas filter assemblies" because the carrier stage being filtered is a gas (air or crankcase ventilation gas). While the technology described herein is typically used in gas filtration applications, it can also be used to filter other materials, such as liquids, if desired.

[0085] The present invention has been described with reference to several embodiments thereof. The entire disclosure of any patent or patent application identified herein is incorporated herein by reference. The foregoing detailed description and examples have been given for clarity of understanding only. No unnecessary limitations should be understood therefrom. It will be apparent to those skilled in the art that many modifications can be made to the described embodiments without departing from the scope of the invention. Therefore, the scope of the present invention should not be limited to the structures described herein, but only by the structures described by the language of the claims and the equivalents of those structures.

Claims

1. 1. An air cleaner assembly for filtering intake air of a power plant, comprising: a) a filter cartridge disposed within a housing of the air cleaner assembly; b) a precleaner assembly including at least one particulate separator for separating particulate matter from the airflow stream and a collection port for discharging the separated particulate matter, the precleaner assembly being positioned upstream of the filter cartridge; c) a collection system for discharging the separated particulate matter from the collection port, the collection system including an electric motor coupled to a fan; d) a control system that manipulates the speed of the electric motor, at least in a normal operating mode, so that the collection system creates a vacuum that draws and expels the separated particulate matter from the precleaner assembly and the collection port, the control system including one or both of a minimum operating state and a high operating state, and when the control system determines that a threshold parameter associated with either the minimum operating state or the high operating state is met, the control system automatically overrides the power output to the electric motor to a different speed; and e) a first pressure sensor positioned to sense pressure between the precleaner assembly and the filter cartridge, wherein the control system transmits an output service signal associated with the precleaner assembly when the pressure sensed by the first pressure sensor exceeds the threshold; and An air cleaner assembly comprising:

2. An air cleaner assembly as described in claim 1, wherein the control system receives an input from the first pressure sensor and sends an output signal to the motor of the collection system based on the input, and the control system determines the pressure within the precleaner assembly based on the sensed pressure at the first pressure sensor.

3. 3. The air cleaner assembly of claim 2, wherein the control system includes a transfer function for determining a pressure within the precleaner assembly based on the sensed pressure at the first pressure sensor, the transfer function including a first correlation between an air mass flow rate through the precleaner assembly and a pressure within the precleaner assembly, and a second correlation between the air mass flow rate through the precleaner assembly and a pressure between the precleaner assembly and the filter cartridge.

4. 3. The air cleaner assembly of claim 2, further comprising a second pressure sensor positioned to sense pressure within said precleaner assembly and providing an input to said control system.

5. 3. The air cleaner assembly of claim 2, wherein the control system operates the collection system motor at a maximum operating speed when the pressure sensed by the first pressure sensor exceeds a threshold value, and / or includes a minimum rotational speed setpoint at which the collection system motor is not operated.

6. 3. The air cleaner assembly of claim 2, wherein said output signal to said scavenge system motor is a rotational speed control signal.

7. 7. The air cleaner assembly of claim 6, wherein said rotational speed control signal is a pulse width modulated (PWM) signal.

8. 8. The air cleaner assembly of claim 7, wherein said control system includes a first map correlating said PWM signal to a pressure drop across said collection system.

9. 9. The air cleaner assembly of claim 8, wherein the control system includes one or more pressure mapping curves correlating a collection fan PWM signal, a flow rate through the collection system, and a pressure signal at the first pressure sensor, and the control system includes a transfer function that generates a collection system motor speed output PWM signal from an input of the first pressure sensor, the transfer function being derived from the first map and the one or more pressure mapping curves.

Images