Abstract: A versatile compact air precleaner, air cleaning method and disposable air filter cartridge for air precleaner for separating heavier-than-air particulate debris from debris laden air to provide a clean airflow, wherein a flow path for air passing through a separator chamber of the air precleaner is retroflexed en route to the outlet. A plurality of independently rotatably adjustable housing sections of a housing provide utility with multiple clean air outlet configurations, freedom of direction of ejection of particulate debris from the ejector ports, different inlet configurations, mounting of the precleaner from different sides, accommodation of different sizes of filters, and different clean airflow rate capabilities. A separator chamber end section including the ejector ports is connected to the filter as a removable, disposable air filter cartridge to obviate ejector port clogging with change of filters.

Abstract: A method and system for expanding, separating, and compressing a multi-phase fluid. An expander receives and expands the multi-phase fluid to generate a lower-pressure fluid which can more efficiently be separated in a separator. Expanding the fluid also drives a main shaft adapted to drive at least the separator and a compressor coupled thereto. The separator receives the lower-pressure fluid, separates any higher-density components from the lower-density components disposed therein, and provides a substantially dry gas to the compressor to be re-compressed and discharged from the system.

Abstract: High molecular weight (HMW) gases are separated from an exhaust gas of a combustion source using a blower and an interior vent within the exhaust stack. The interior vent includes a vent wall having a top portion attached to the interior surface of the exhaust stack along the entire inner perimeter of the exhaust stack and a lower portion that extends downward into the exhaust stack to form an annular space or gap between the vent wall and the interior surface of the exhaust stack, and at least one opening in the interior surface of the exhaust stack between the top and bottom portions of the vent wall. The blower creates a tangential flow of the exhaust gas with sufficient centrifugal force to concentrate substantially all of the HMW gases along the inner surface of the exhaust stack. A transfer pipe removes the HMW gases from the interior vent.

Abstract: The present invention relates to a separator and more specifically, but not exclusively, to a centrifugal separator for the cleaning of a gaseous fluid. A centrifugal separator is provided as comprising a housing defining an inner space, and a rotor assembly for imparting a rotary motion onto a mixture of substances to be separated. The rotor assembly is located in said inner space and is rotatable about an axis relative to the housing. The rotor assembly comprises an inlet for receiving said mixture of substances, an outlet from which said substances are ejected from the rotor assembly during use, and a flow path for providing fluid communication between the inlet and outlet, wherein the outlet is positioned more radially outward from said axis than the inlet.

Abstract: High molecular weight (HMW) gases are separated from an exhaust gas of a combustion source using a blower and an interior vent within the exhaust stack. The interior vent includes a vent wall having a top portion attached to the interior surface of the exhaust stack along the entire inner perimeter of the exhaust stack and a lower portion that extends downward into the exhaust stack to form an annular space or gap between the vent wall and the interior surface of the exhaust stack, and at least one opening in the interior surface of the exhaust stack between the top and bottom portions of the vent wall. The blower creates a tangential flow of the exhaust gas with sufficient centrifugal force to concentrate substantially all of the HMW gases along the inner surface of the exhaust stack. A transfer pipe removes the HMW gases from the interior vent.

Abstract: A dust collection device includes a machine body that forms an air chamber and a chassis arranged below the machine body. The chassis receives therein a dust collection tank. A mechanics case that contains a motor and blower assembly is arranged at one side of the machine body. The mechanics case includes a partition board to divide the mechanics case into an inlet flow channel communicating the air chamber and an outlet flow channel for discharging air. The partition board forms an air vent hole in communication with the outlet flow channel. A block unit is provided on the partition board and includes a block plate that selectively blocks the air vent hole. When a fire occurs inside the air chamber, the partition board prevents the fire flame from being drawn into the mechanics case, and the block plate timely blocks the air vent hole to improve operation safety.

Abstract: An air intake system (20) for a utility vehicle engine (16) is provided. The system comprises an air filter module (21) having a pre-filter (22) upstream of a main filter (24) wherein the pre-filter serves to extract dust from the air stream. The system further comprises a fan module (32) which is dedicated to deliver a scavenging vacuum which sucks said dust through a scavenger vent (28) in the pre-filter. The fan module (34) is secured to the air filter module (21). By providing a dedicated fan for extracting the dust from the system the reliance on the engine exhaust to provide the vacuum is removed. Furthermore, the securing of the fan module to the air filter module reduces the number of components on the vehicle assembly line.

Abstract: A method of reducing silicosis caused by inhalation of silica-containing proppant, such as silica sand and resin-coated silica sand, and apparatus therefor. The abstract of the disclosure is submitted herewith as required by 37 C.F.R. §1.72(b). As stated in 37 C.F.R. §1.72(b): A brief abstract of the technical disclosure in the specification must commence on a separate sheet, preferably following the claims, under the heading “Abstract of the Disclosure.” The purpose of the abstract is to enable the Patent and Trademark Office and the public generally to determine quickly from a cursory inspection the nature and gist of the technical disclosure. The abstract shall not be used for interpreting the scope of the claims. Therefore, any statements made relating to the abstract are not intended to limit the claims in any manner and should not be interpreted as limiting the claims in any manner.

Abstract: Segmented stackable filter assembly for filtering a gas and method of manufacturing same. An exemplary embodiment of the segmented stackable filter assembly comprises a plurality of filter segments stackable end-to-end for varying filtration capacity of the stackable filter assembly. Each filter segment includes an annular outer wire mesh and an annular inner wire mesh spaced apart from the outer wire mesh to define a gap therebetween containing filter media. The inner wire mesh defines a central air flow passage axially through the filter assembly. A lower end plate has an opening for receiving a neck portion upwardly projecting from an adjacent upper end plate, so that both filter segments are prevented from laterally moving relative to each other. A fan assembly is supported by the neck portion for suctioning the gas through the plurality of filter segments.

Abstract: Embodiments of recirculating filtration and exhaust systems for material processing systems are disclosed herein. A material processing system configured in accordance with one embodiment includes an enclosure for processing a workpiece, the enclosure having an enclosure inlet and an enclosure outlet. The system also includes a first flow path fluidly coupled to the enclosure inlet and the enclosure outlet, and a first filtration assembly in the first flow path. The first filtration assembly draws airflow from the enclosure and returns the airflow to the enclosure. The system further includes a second flow path in fluid communication with the first flow path upstream from the enclosure inlet, and a second filtration assembly in the second flow path. The second filtration assembly draws airflow from the first flow path and returns airflow to the first flow path.

Abstract: A biofilter (1) having filter media (7) in a stowage space (5) having sidewalls and a bottom, inlet opening (15) for the unpurified gases/air and the stowage space (5) is made of flexible gas-tight material filled at least partly with the filter media (7). A biofilter system having two or more biofilters (1) is also described.

Abstract: Disclosed are various embodiments of a filtration lighting system. In one embodiment, the filtration lighting system includes at least one light source, a circulation fan, at least one air filter, and a housing. The housing includes at least one air inlet and is configured to house the light source, the circulation fan, and the at least one air filter.

Abstract: An agricultural work vehicle includes an enclosed engine compartment within the vehicle body, with the engine compartment having a top cover that extends generally between opposite sides of the vehicle body. A vertically oriented air inlet is defined in the vehicle body for intake of air into the engine compartment. An intake housing is configured over the air inlet and includes an inlet opening and an outlet opening in communication with the engine compartment air inlet. The inlet opening extends above the top cover and is oriented relative to a vertical plane such that an angled air flow path is defined between the inlet opening and the outlet opening wherein air is drawn from an area above the top cover of the engine compartment and is directed into the air inlet.

Abstract: A filter support casing and filter provides powder into a Bernoulli flow system. The system has an upper end and a lower end, the upper end having an opening therein. The filter support casing extends downward from the upper end. There is a filter supported within the casing. The filter support casing and the filter define an internal volume within both the filter support casing and the filter. The volume is exposed to the opening in the upper end and as later explained is flow connected into a gas stream that will carry particles and spray particles. The casing has at least two concentric elements, a first inner elements and a second outer element, that rotate with respect to each other and which slide with respect to each other. The two elements rotate about their concentric positions and slide along their lengths. The first inner element is contiguous (adjacent and/or touch and adjacent) with the filter. The first inner element encloses the filter with arms (fingers, extensions, posts, etc.

Abstract: Z-filters capable of cleaning particulate matter from airflow streams in dust collectors, including reverse flow, reverse air, and reverse pulse systems.

Abstract: A method of reducing silicosis caused by inhalation of silica-containing proppant, such as silica sand and resin-coated silica sand, and apparatus therefor. The abstract of the disclosure is submitted herewith as required by 37 C.F.R. §1.72(b). As stated in 37 C.F.R. §1.72(b): A brief abstract of the technical disclosure in the specification must commence on a separate sheet, preferably following the claims, under the heading “Abstract of the Disclosure.” The purpose of the abstract is to enable the Patent and Trademark Office and the public generally to determine quickly from a cursory inspection the nature and gist of the technical disclosure. The abstract shall not be used for interpreting the scope of the claims. Therefore, any statements made relating to the abstract are not intended to limit the claims in any manner and should not be interpreted as limiting the claims in any manner.

Abstract: A filter box for a surface maintenance machine incorporating aspects of a fan housing. In one example, a filter box for a sweeping machine is provided with an impeller fan housing beneath a cylindrical filter. Operation of the impeller fan draws air from a debris hopper, through the cylindrical filter, and through an expansion chamber defined by a scroll conduit prior to outlet to atmosphere.

Abstract: The present invention provides a dust collector structure, especially a low-cost and simplified dust collector structure, which includes a leg frame set, an air-guiding box and a driving unit. The leg frame set includes two inverted U-shaped frame rods which are integrally formed and correspond to each other. The air-guiding box is arranged across top ends of the two frame rods, and is made by correspondingly closing an upper cover and a lower cover which are formed through integral draw molding. A driving unit for driving a blowing fan is arranged at an end of the air-guiding box. An air-filtering bag and a dust-collecting bag corresponding to each other are arranged at an end opposite to the driving unit on the upper and lower covers of the air-guiding box. Thus, structural components can be greatly simplified.

Abstract: A surface cleaning apparatus comprises an air flow path extending from a dirty air inlet to a clean air outlet, an air treatment member and a suction motor. The surface cleaning apparatus comprises a main body comprising a front end and a rear end, first and second opposed sidewalls and a suction motor housing. At least one of the first and second opposed sidewalls may have a suction motor access opening.

Abstract: A portable air filter having a cylindrical, perforated shell with an end wall at one end closing the shell and an end wall at the other end having an opening. A hepa filter is removably mounted within the shell adjacent the perforations. The air filter has a blower unit with a through duct and a fan and a motor in the duct. The blower unit is detachably mountable on the shell adjacent the end wall at the other end with one open end of the duct extending through the opening in the end wall. Air is drawn through the perforated shell and hepa filter into the duct and out of the duct through its other open end away from the air filter.

Abstract: An image forming apparatus includes a duct, a fan, a guide duct, and a filter. Air flows through the duct from an intake port in a front face of an apparatus body toward a first exhaust port in a rear face. The fan is provided in the duct and takes in the air via the intake port and exhausts the air via the first exhaust port. The guide duct is provided at the rear face, covers the first exhaust port and a second exhaust port via which exhaust air containing an odorous component produced inside the apparatus body is exhausted from the rear face, and guides the exhaust air from the first and second exhaust ports upward in a vertical direction. The filter is provided in the guide duct downstream from the first and second exhaust ports in the vertical direction and removes the odorous component from the exhaust air.

Abstract: A dust collection system has a cyclone separator in which dust is separated from an air stream and the air stream is passed from a separator and flows through a final filter back into the ambient air. A flame arrester is positioned downstream of the separator, either in advance of or after the final filter. The flame arrester defines a multiplicity of narrow channels to permit exhaust air flow but block any flame front. In a preferred embodiment the flame arrester is in the form of a sheath of a porous metal material surrounding the final filter. The sheath may comprise a metal wire mesh screen, with a guard cage surrounding the screen.

Abstract: A dust collector arrangement has a dust separator supported on a frame, with a lid for the dust collection barrel is mounted onto the frame below it. The lid is supported at a fixed elevation above the surface of the shop floor to create a space or clearance between the rim of the dust collection barrel and the lid. The barrel is supported on casters, and can be rolled into place under the rim, and can be rolled out for emptying. Over-center latches positioned at intervals around the upper part of the barrel side wall, engage corresponding structure on the lid. These pull the barrel upwards against the lid and with the barrel casters lifted off the floor surface. The latch members release to lower the barrel for emptying.

Abstract: A dust collection arrangement employs a variable frequency drive to supply AC to its fan motor. A current sensor measures the current drawn by the motor, and this is compared with a preset value. The variable frequency drive adjusts the frequency of the AC applied to the motor to maintain the motor current at the preset level. This keeps the flow of air in the system optimal as dust producing tools are added or taken off.

Abstract: Improvements in a filter where the filter self-expands based upon increased pressure or vacuum in the filtering stream. The expandable filter is adaptable to filtering a wide variety of media including air used in HVAC units, gases that are used to filter impurities out of gases and for industrial applications. The expandable filter to maintain a constant pressure or vacuum in the plenum or filter. The filter self-expands as the pressure or vacuum increases and pushes, pulls or draws the filter into an elongated or heightened configuration. As the filter expands new filter material is exposed that was not previously exposed for filtering. Expansion doubles, triples, or further increases the filter collection surface area. The filter does not rely upon gravity and expands based upon the increase of pressure or vacuum in the plenum the filter can be arranged in a vertical or horizontal orientation.

Abstract: This patent pertains to self-cleaning fan assemblies. One implementation includes electronic components positioned in an enclosure. This implementation also includes a fan assembly that is configured to impart rotational force on air to move the air from outside the enclosure to inside the enclosure and around the electronic components. The fan assembly is further configured to separate contaminants from the air based upon differences in density between the contaminants and the air.

Abstract: A system for separating contaminants from an airstream, including a centrifugal fan and housing; a contaminant containment vessel mounted to an outer surface of the housing; and a diverter in the airstream downstream of the fan and within the housing, the diverter being configured to separate a portion of the airstream from a remainder of the airstream, accelerate the portion of the airstream towards the containment vessel, and thereafter guide the portion of the airstream towards the remainder of the airstream. The diverter preferably does not negatively impact the rated performance of the fan, such that a performance of the system is not measurably different than the rated performance of the fan and housing combination. The diverter may accelerate contaminants entrained in the airstream toward the containment vessel, thereby separating the contaminants from the airstream.

Abstract: A portable handheld canister vacuum including an upper, central, and lower housing is disclosed. First and second grills can separate the housing sections. An air intake opening can direct air and dirt in a first axial direction to a dirt capturing device in the lower housing. An air propulsion device directs air in a second axial direction opposite to the first axial direction into the central housing and from there into the upper housing. An exhaust opening disposed through the upper housing and leading to the interior region of the upper housing allows air to exit the interior region of the upper housing. The exhaust can exit the upper housing in a direction substantially perpendicular to the first and second axial directions.

Abstract: A chimney filter system featuring two or more filter housings mounted atop an industrial chimney stack and a reservoir fluidly connected to the lower filter housing via a first drain pipe that allows water to flow from the lower filter housing to the reservoir. The reservoir allows contaminants in the water to collect on the bottom surface of the reservoir. A second drain pipe is fluidly connected to the reservoir via a pump. The pump and second drain pipe deliver water from the reservoir to the upper filter housing.

Abstract: A mobile laminar flow hood specifically devised for use in podiatry and a podiatric apparatus to which such hood is associated are described. The hood is adapted to generate a laminar flow of sterile air. In particular, an apparatus comprises a system for the generation and treatment of a laminar air flow in an intervention zone is described, together with means to support the system for the generation and treatment of a laminar air flow. The system has a blowing hood adapted to generate a laminar flow of sterile air towards the intervention zone, and a suction hood adapted to suck the laminar flow of sterile air from the intervention zone.

Abstract: A method for operating a ducted fumehood with increased energy efficiency, wherein the method includes passing exhaust air from the ducted fumehood through a heat exchanger, and passing other air through the heat exchanger, so as transfer heat content from the exhaust air to the other air, or to transfer heat content from the other air to the exhaust air, so as to temperature-condition the other air.

Abstract: A particle separating structure for use with a turbine engine. The particle separating structure includes a main housing, first swirling structure, and second swirling structure. The first swirling structure is provided for swirling cooling fluid passing through a first cooling fluid flowpath defined in the main housing. The second swirling structure is provided for swirling cooling fluid passing through a second cooling fluid flowpath defined in the main housing. The first swirling structure is positionable in at least two positions, a first position allowing cooling fluid to pass through the first cooling fluid flowpath and a second position allowing cooling fluid to pass through the first and second cooling fluid flowpaths. The swirling of the cooling fluid causes particles in the cooling fluid to pass to a particle discharge zone while the cooling fluid passes out of the main housing through a cooling fluid outlet.

Abstract: An air cleaner that filters air supplied into an engine may include a lower case that has an intake port through which external air flows inside, a filter that may be disposed in the lower case and filters and allows the air flowing inside through the intake port, and an upper case that may be coupled to an upper portion of the lower case and has an exhaust pipe to discharge the air filtered by the filter to the engine, wherein an inlet of the exhaust pipe may be formed inside the upper case and an outlet may be formed to be connected to the outside of the upper case, the inlet of the exhaust pipe may be divided into a first inlet and a second inlet, and a fan that controls the exhaust amount of air to the outlet of the exhaust pipe may be disposed in the second inlet.

Abstract: A portable dust collection air cleaner assembly is provided. A access hatch is hinged to a dust collection bin to provide ready access to the filter element. The filter element may include an outer annular flange carrying a gasket that rests upon, engagement and seals against a top panel of the dust collection bin.

Abstract: The invention refers to a plant and a method for separating oil in form of particles and/or mist from a fossil gas mixture for obtaining a separated gas. The plant comprises a centrifugal separator with a stationary casing defining a separation space. The casing permits a pressure of at least 10 bars in the separation space. The centrifugal separator comprises an inlet for the gas mixture, a gas outlet for the separated gas and an oil outlet for discharging separated oil. A separating member for separating the gas mixture comprises a plurality of separating discs and is provided in the separation space. A drive motor is connected to the separating member via a spindle and rotate the separating member about an axis (x) of rotation.

Abstract: The present invention provides an air filter including a main body, a pressure fan, a filter mode and a fixing assembly. The main body has a containing room, an entrance hole and an exit hole. The pressure fan is disposed in the containing room. The filter mode includes a first filter layer, a second filter layer and a frame body. The first filter layer is disposed in the entrance hole, and the second filter layer is disposed in the frame body. As such, users can select to use only the first filter layer or both filter layers at one time. Moreover, users only need to let the frame body pivot to a position away from the entrance hole so that users can change the filter layers faster and easier.

Abstract: An air filtration system includes a housing that is interchangeably positioned within a plenum that is in fluid communication between the housing and a room. A fan is positioned within the housing and configured to draw contaminated air from the plenum. At least one filter member is positioned within the housing and configured to filter the contaminated air. A flexible duct is configured to channel filtered air from the housing to the room. The flexible duct is configured to enable the interchangeability of the housing.

Abstract: Devices, methods and systems for creating a zone of filtered air proximate a head of a user including an air filtration device including a blower being configured to be disposed within, below, or affixed to a bedding structure, an air plenum in flow communication with the blower and in support of the head of the user and having an air delivery surface configured to distribute the air flow to the zone of filtered air, and a filter disposed within the device for filtering the air flow before it is distributed to the zone of filtered air.

Abstract: A dust-sucking and air-cleaning composite structure is provided with a dust-sucking body and an air-cleaning body. The top surface of the air-cleaning body is provided with a vertically opening cavity. The cavity is recessed downward toward the interior of the air-cleaning body and has an opening facing upwardly. The inner profile of the cavity corresponds to the outer profile of the dust-sucking body, thereby allowing the dust-sucking body to be movably inserted into the cavity to be electrically coupled to the air-cleaning body.

Abstract: A system and method for the treatment of a fluid comprising at least two of the fractions solid particles, liquid and/or gas is described having at least one inlet portion and two or more outlet portions, and being arranged to separate solid particles over a predetermined size from the liquid by at least one screening apparatus and then carrying the fractions out of the system. The system (1) being substantially fluid-tight between the at least one inlet and outlet inlet portions and being provided with at least one underpressure-generating device arranged to provide an underpressure in the system.

Abstract: A filtration system has a blowdown conduit and a filter unit. The blowdown conduit is adapted to be operably connected with a gas compressor station. The filter unit includes a filter housing, an inlet port, a pollution filter positioned within the filter housing to remove the pollutants from the vented gasses entering through the inlet port, and an exit port enabling the vented gasses to exit the filter housing once the pollutants have been removed by the pollution filter.

Abstract: A modular apparatus for processing air for classified environments and processes for preparing foods in general is constituted by a recovery air and outside air suction section with an optional free cooling fan; an air mixing section; a filtering section; a cold and hot battery section; a spacing section between the batteries of the cold and hot battery section; an air delivery ventilating section; an optional absolute filtering section; and an air delivery section.

Abstract: The system for decontaminating industrial output gases may process both particulate and gaseous emissions from industrial facilities. The system may be located with or adjacent to an industrial facility or at some distance from the facility. In one embodiment the system includes a subsystem of alternating active and inactive filters, and a wash subsystem cleaning the inactive filters during the cycle. The wash water is captured in a basin for further processing of the chemical particulates therein. Fans located downstream of the filters draw the gaseous industrial output through the filters. Remaining vapor passes to a classification plant where the gases are separated into their constituent elements or compounds. Gases that to are allowed to escape may be burned, and the resulting gases recirculated through the system. Another embodiment is adapted for processing steam, and cools the steam for use as liquid water, rather than allowing it to escape as vapor.

Abstract: A cyclonic dust collector arrangement employs a cyclone that has a conic body formed of a conic wall. An upper divider plate closes off the upper end of the conic body, with a vortex tube descending from a central passage in the divider plate. The conic body has a narrow nose at a lower end so that the upper divider plate and the lower nose define a cyclonic chamber within the conic body. The inlet conduit penetrates the conic wall below the divider plate. The fan chamber of the separator is mounted above the divider plate, and serves to induce air flow from the inlet conduit into the cyclonic chamber, and through said vortex tube into the fan chamber. The air is discharged through a final filter. This construction has reduced manufacture costs and improved dust separation.

Abstract: Apparatus and methods for reducing or eliminating undesirable air-borne substances, such as odors, bacteria, viruses, fungi, and toxins, are provided. A filter containing nanocrystalline metal oxide or metal hydroxide particles may be installed within an air handling apparatus such as an existing HVAC unit located within a building, and particularly within a home, or a portable air processor or purifier. The air handling apparatus comprises a blower which pulls air containing various undesirable substances from within the enclosed environment and directs it through a filtering device containing the nanocrystalline particles. The undesirable substances are sorbed by the nanocrystalline particles thereby creating a deodorized stream of air that may then be directed back into various portions of the enclosed environment or vented to the atmosphere.

Abstract: In various embodiments, a support system includes a multi-layer cover sheet with a number of layers. In certain embodiments, a source to move air inside and outside the multi-layer cover sheet can be provided. The source can include a source of positive pressure or negative pressure.

Abstract: A method for separating mixed granular material based upon dissimilar specific gravities, (such as in firearm range cleaning) thereby separating lead from backstop material. Lead falling from an airstream is airwashed by an upwardly directed second airstream. The preferred method is performed under negative pressure to control lead dust. Application to pick up and clean or recover fouled ballast rock (such as used in the rail industry). Processes and apparatus are disclosed that pick up and clean or enrich precious metal bearing ore.

Abstract: The present invention relates to a system and method for the separation of gaseous components from gaseous mixtures in order to control emissions and treatment of the gaseous components. In one embodiment, the system makes use of a fan or gas moving device to first impose centrifugal forces on gas streams as the gas moves from the center of the fan toward the periphery of the fan housing. Heavier gases are forced to the outer regions of the fan housing while lighter gases remain closer to the fan axis. The heavier gases and lighter gases exiting the fan housing flow into a duct at different flow rates, and the heavier gases are diverted from the larger volume gas streams and then processed.

Abstract: This invention relates to hovering vacuum cleaners and components therefor. Specifically improvements to the filtering system and air handling capabilities of the vacuum cleaner are disclosed.

Abstract: The present invention is a device that rapidly and effectively separates and collects debris from airflow between a debris source and a vacuum source. The device comprises a first chamber situated above and adjoining a second chamber. The first chamber functions to separate and remove the debris and the second chamber functions to collect the debris. The first chamber is circular in cross-section and comprises an upper portion and a downward and outward sloping sidewall. The upper portion has an output port connected by a first conduit to the vacuum source and the sidewall has an input port connected by a second conduit to the debris source. Air and debris are drawn into the first chamber through the input port by suction created at the output port. The debris is centrifugally forced to the sidewall whereby it is then centripetally forced downward into the second chamber through a peripheral opening between the sidewall and a barrier, while cleaned air is evacuated through the output port.