Abstract: A filter for filtering a fluid has a filter housing and a filter element arranged in the filter housing. A cyclone preseparator is arranged upstream of the filter element, wherein a fluid to be cleaned is guided through the preseparator to the filter element. The cyclone preseparator has at least two cyclone cells that have a different diameter, respectively.

Abstract: Cyclonic separating apparatus for a cleaning appliance such as a vacuum cleaner has a longitudinal axis, an upstream cyclonic separator and a downstream cyclone assembly. The downstream cyclone assembly comprises a plurality of cyclones arranged in parallel with one another. The downstream cyclones are arranged in a first set in which each cyclone has a longitudinal axis inclined at a first angle (?) to the longitudinal axis of the cyclonic separating apparatus and a second set, in which each cyclone has a longitudinal axis inclined at a second angle (?) to the longitudinal axis of the cyclonic separating apparatus. The second angle (?) is greater than the first angle (?). The invention allows the downstream cyclone assembly to be compactly packaged.

Abstract: Embodiments of the invention include a dust extraction system including an array of two or more centrifugal dust removal devices, e.g., axial cyclones. The array of axial cyclones is configured to operate in parallel. The array of axial cyclones includes one or more sensor and a controller in communication with the sensor and adapted to receive air flow information from the one or more sensor. Inflow valves are operatively connected to the controller such that air flow through the array of axial cyclones is monitored and maintained at an optimum operating condition for each of the individual cyclones in the array. This is done, in general, by opening inflow valves as the air flow increases above a predetermined air flow value and shutting inflow valves as air flow decreases below the predetermined air flow value threshold.

Abstract: A cyclone separating device of a cleaner includes an upstream cyclone separating device and a downstream cyclone separating device. The upstream separating device communicates with the downstream cyclone separating device through a gas passage. The upstream cyclone separating device has a first cyclone barrel, while the downstream cyclone separating device has at least one second cyclone barrel. The downstream cyclone separating device is lying and set above the upstream separating device. The size of the cyclone separating device of the present invention is small in radial direction. The height of the cyclone separating device which is the sum of the height of the upstream cyclone separating device plus the height of the lying downstream cyclone separating device lying down is low.

Abstract: Apparatus for separation of particles from a fluid stream entraining said particles comprises an inlet zone, a centrifugal separation zone, particles collection means and exhaust means, in which the inlet and separation zones are in communication via a transition zone for inducing vortical flow in the fluid stream, the transition zone having a diameter greater than the diameter of the inlet zone and comprising means defining an outlet port to the separation zone, an entry port being formed in the transition zone upstream of the baffle means, the entry and outlet ports being mutually arranged to minimise fluid perturbation in the fluid stream in use.

Abstract: In order to provide an intake system for sucking in combustion air of an internal combustion engine of a piece of equipment, in particular a portable, manually guided piece of equipment, having more than one centrifugal separator comprising a centrifugal separator housing, and having an air filter device comprising an air filter housing, which bounds an air filter receiving space for an air filter, in which the combustion air can be separated by means of the centrifugal separator into a core volume stream and an outer volume stream, wherein the core volume stream is fed to the internal combustion engine through the air filter receiving space, which intake system is as compact as possible and correspondingly designed to be not very component-intensive, it is proposed for the centrifugal separator housing to be arranged on the air filter housing such that it ends directly at the air filter receiving space or projects directly into the air filter receiving space.

Abstract: A dual cyclone dust-collecting apparatus of a vacuum cleaner is disclosed. The dust-collecting apparatus includes an air inlet through which an external air is drawn in, two cyclone chambers into which the external air drawn in through the air inlet air is drawn in, the two cyclone chamber being disposed in parallel, at least one dust-collecting chamber divided in parallel with respect to the two cyclone chambers, and two air outlets through which the external air from the two cyclone chambers is discharged. The air inlet is formed between the two cyclone chambers at a lower part of a cyclone body and the two air outlets are formed in bottom surfaces of the two cyclone chambers, respectively, so that the external air is drawn in through lower parts of one sides of the two cyclone chambers and then discharged through the bottom surfaces of the two cyclone chambers.

Abstract: An indoor vacuum cleaner comprises a dirty air inlet, a handle, a cyclone separator having an outer wall, a fluid inlet downstream from the dirty air inlet and a fluid outlet, a plate having a cyclone chamber surface and positioned to substantially divide the cyclone separator into a cyclone chamber and a dirt collection chamber, each of the cyclone chamber and the dirt collection chamber having an outer wall, the outer wall of each of the cyclone chamber and the dirt collection chamber having an outer perimeter, the dirt collection chamber having a cyclone chamber end spaced from a dirt collection floor, a passage extending between the cyclone chamber and the dirt collection chamber, the passage configured such that separated dirt travels at least outwardly as the dirt travels through the passage and, an air flow motor.

Abstract: A fluid separating vessel (1) comprises: a liquid outlet (3) near the bottom of the vessel; a gaseous fluid outlet (4) near the top of the vessel; a plurality of cyclones (5) arranged in an upper region of the vessel in which at least some liquid droplets that may be entrained in the substantially gaseous fluid stream flowing in upward direction from a fluid inlet (2) towards the gaseous fluid outlet (4) are coalesced, separated from the gaseous carrier fluid and induced to drip down towards the liquid outlet (3) via a liquid return conduit (7); and a plurality of rotating liquid coalescing centrifuges (8) that are arranged below the cyclones (5), in which liquid coalescing centrifuges (8) fluid fed to the cyclones (5) is pre-treated such that at least some liquid droplets that may be entrained in the substantially gaseous fluid stream flowing in upward direction from the fluid inlet towards the cyclones are coalesced.

Abstract: Process to separate particles from a particles-containing gas stream, by subjecting the particles-containing gas stream to a centrifugal separation step, wherein the particles-containing gas stream is separated in a gas rich flow and a particles-rich flow and wherein the particles-rich flow is cooled from a temperature in the range from 600 to 800° C. to a temperature in the range from 200 to 450° C. before it is subjected to a second separation step, wherein particles are separated from the particles-rich flow.

Abstract: A vacuum cleaner including multiple cleaning stages comprises a first cyclonic stage and a second cyclonic stage, which is spaced from the first cyclonic stage. A housing defines a first particle collector that communicates with the first cyclonic stage. The first particle collector includes an opening. A removable lid covers the first particle collector opening. A second particle collector in communication with the second cyclonic stage is removable with the lid. A suction motor is supported by the vacuum cleaner. The suction motor establishes and maintains a flow of air through the vacuum cleaner.

Abstract: A filter for filtering a fluid has a filter housing and a filter element arranged in the filter housing. A cyclone preseparator is arranged upstream of the filter element, wherein a fluid to be cleaned is guided through the preseparator to the filter element. The cyclone preseparator has at least two cyclone cells that have a different diameter, respectively.

Abstract: A cyclone silencer of cleaner includes an outlet pipe(2) partially inserted into a cyclone cylinder (1). Ribs (3) are arranged on the lower edge of said outlet pipe (2) and extend downwardly to reduce noise.

Abstract: A grease filter has a filtering portion configured such that fumes enter a major face thereof and flow through a grease extraction filter therewithin in a direction parallel to the major face. A frame that fits into an opening of a hood defines a box structure that is configured to allow flow from the end (or ends) of the filtering portion where flow exits. The frame permits the flow to exit to a side opposite the face even when the frame is surrounded, edgewise, by a solid structure of the hood opening.

Abstract: A labyrinth box can include a housing that has an open end, a closed end, and defines two cavities. A cover is configured to cover the opening and can include a divider that extends into one of the two cavities of the housing to define first and second chamber passageways in that cavity. An inlet port is located in the bottom closed end of one of the cavities and an outlet port is located in the other of the cavities. The surfaces that define the chambers can be configured such that the box can be oriented in different positions and still work, namely, in horizontal and vertical positions. When in the vertical position, the divider can include surfaces that are angled off of the horizontal plane and towards the inlet port such that water and debris will return to the inlet port via gravity.

Abstract: A cyclonic separation apparatus comprises a plurality of series-connected separation stages 50,51, each comprising a plurality of cyclone separators 16/23 connected in parallel and disposed in a generally annular arrangement about a main vertical axis of the apparatus, with their respective longitudinal cyclone axes extending parallel to the main axis. The successive separation stages 50,51 in the direction of fluid flow are disposed radially inwardly of each other with respect to the main axis of the apparatus and are also vertically staggered upwardly, so that the outlet 20 of one separation stage 50 leads directly into the inlet 22 of the next downstream stage 51. The multi-stage, series connected cyclone separators of the apparatus provide a high separation efficiency, yet the annular arrangement of the stages 50,51 makes the apparatus compact and enables the apparatus to be utilized in a vacuum cleaner.

Abstract: A cyclonic separation apparatus comprising at least two series connected separation stages and a receptacle for collecting material separated by the separation stages is described. The first stage comprises a first cyclone separator, and the second stage comprises a plurality of parallel connected second cyclone separators. The first and second separation stages are connected by at least one transfer duct which extends through the receptacle and transfers fluid that has been partly cleaned by the first separation stage to the second separation stage.

Abstract: A cyclonic vacuum cleaner comprises a first stage 10 comprising a single cyclone separator for separating heavier dirt and dust particles and a second stage 11 comprising a plurality of cyclone separators 25 arranged in parallel in a plurality of groups, each group of cyclone separators 25 comprising a respective inlet duct 24, each inlet duct 24 being connected at its upstream end to the first stage 10 and at its downstream end to the cyclone separators 25 of its respective group.

Abstract: The invention concerns a separating device for separating particles (4) from a gas stream (2) in which the gas stream (2) by means of a guiding device is caused to rotate and the liquid or solid particles (4) to be separated are removable by a particle outlet. The separating device (1) is comprised of a cylindrical housing pipe (5) with a guiding device (3) and an immersion pipe (6) arranged in alignment with the flow direction of the gas stream (2) in the housing pipe (5) which immersion pipe is provided on the exterior with a spiral (7) for a directed removal of the particles (4) separated by rotation to a housing opening (8) and with a central outlet (9) for the purified gas stream (2).

Abstract: A surface cleaning apparatus comprising a dirt inlet, a handle, a first cyclonic cleaning stage, a second cyclonic cleaning stage comprising a plurality of cyclones in parallel and a plurality of dirt collection chambers that are emptied concurrently, and the first cleaning stage is removed from the second cleaning stage prior to emptying the plurality of dirt collection chambers and, an air flow motor.

Abstract: A cleaning appliance includes a main body, a filter and an interlock. The main body includes an airflow generator, a separating apparatus separating dirt and dust from an airflow, and a flowpath between the separating apparatus and the airflow generator delimited by a wall. The interlock has a first part located on the filter and a second part located on the main body outside the flowpath, arranged to communicate remotely when the filter is correctly located in the pre-determined position. The interlock is arranged selectively to allow or prevent operation of the airflow generator depending upon the relative separation between the first and second parts. By providing an interlock which has first and second parts which communicate remotely, the second part located on the main body can be isolated from the airflow path so that the second part is not subject to dirt and dust carried by the airflow.

Abstract: An oil mist separator includes a body inside which a filtering chamber is formed for a filtering unit made up with several centrifugal dust collectors. With an air intake unit, the outside oil mist is sent into the filtering chamber. Then, the centrifugal dust collectors are used to cause a spiral airstream. With a centrifugal force caused by the spiral airstream, the oil mist is made to separate from the air. Next, the filtered air of zero pollution is vented to the atmosphere, and the separated oil mist is collected and recycled. Thus, the oil mist may be separated and the recycled oil mist may be made into a low-level oil product or a release agent used in the building industry for achievement of the effect of environmental protection.

Abstract: Object of the present invention is to provide a dust collecting device (100) for a vacuum cleaner of which dust collecting performance is improved. For this, the dust collecting device (100) includes a primary cyclone unit (110) having two parallel primary cyclones (111,112) for separating dust form air introduced therein by a cyclone principle, and a secondary cyclone (120) unit at a downstream of the primary cyclones (111,112) for cleaning the air again by the cyclone principle.

Abstract: A portable appliance comprises a dirt inlet, first and second cyclonic stages wherein each cyclonic stage comprises a plurality of cyclones in parallel and the second cyclonic stage is downstream from the first cyclonic stage and a fluid flow motor.

Abstract: A dust separating apparatus of a vacuum cleaner, includes a housing, a first cyclone separator integrated within the housing, and second cyclone separators arranged around the first cyclone separator, wherein the second cyclone separators are removably mounted into the housing. The first and second cyclone separators respectively have a separate dust receiving cavity and separate dust collecting chambers.

Abstract: A multi-cyclone dust-collecting apparatus for a vacuum cleaner mounted in a main cleaner body to separate dust from air flowing from a suction port body and collect the dust separated from the air, the apparatus including a dust-separating unit including a primary cyclone unit to separate large dust particles contained in the air flowing from the suction port body, and a secondary cyclone unit that is disposed inside the primary cyclone unit and that tapers downwards; and a dust-collecting unit detachably mounted in a lower portion of the dust-separating unit, the dust-collecting unit including a first dust-collecting chamber to collect the large dust particles discharged from the primary cyclone unit, and a second dust-collecting chamber disposed inside the first dust-collecting chamber to collect fine dust particles discharged from the secondary cyclone unit. The first dust-collecting chamber may be greater in volume than the second dust-collecting chamber.

Abstract: A cyclone dust-collecting apparatus is provided. The dust-collecting apparatus is detachably mounted in a main cleaner body of a vacuum cleaner and disposed on a suction flow path extending from a suction port body to a suction source. The dust-collecting apparatus includes a body having an opened lower portion; at least one cyclone unit disposed to one side in the body to separate dust from air flowing into the body and discharge air from which the dust has been separated; and a bottom cover to open or close the lower portion of the body. The body has an inflow pipe penetrating the body from a rear portion of the body and connected to the cyclone unit and the inflow pipe has an inclined top surface.

Abstract: A cyclone dust collector includes a cyclone body including a first cyclone chamber to centrifugally separate dust from drawn-in air for a first time, a plurality of second cyclone chambers to centrifugally separate dust from the drawn-in air for a second time, and a plurality of discharge ports to cause the drawn-in air to be discharged from the plurality of second cyclone chambers; an upper cover to cover an upper portion of the cyclone body, the upper cover having an inner wall facing the plurality of discharge ports; and a noise reduction part disposed between the plurality of discharge ports and the inner wall of the upper cover, to reduce noise generated inside the upper cover by the air discharged through the plurality of discharge ports. Therefore, it is possible to reduce noise generated inside the upper cover of the cyclone dust collector.

Abstract: An inertial separator comprising a tubular body, the tubular body comprises a composition comprising a polymer selected from the group consisting of a cyclic olefin polymer and a cyclic olefin copolymer, and, a polyhedral oligomeric silsesquioxane and/or a flame retardant and/or an anti-static additive, is disclosed.

Abstract: A cyclonic cleaning stage for a, e.g., surface cleaning apparatus is provided. The cyclonic cleaning stage comprises a plurality of cyclones, which are integrally molded as a single body. Each cyclone has a cyclone body having an upper end, a lower end, a cyclone inlet, and a cyclone outlet. Each cyclone inlet has a top. A separately molded upper cover is mounted to the top of the single body at the upper ends. A separately molded lower cover is mounted on the single body at the lower ends of the cyclones.

Abstract: A multi-cyclone dust separator is provided, including a first cyclone unit that centrifugally separates dust from dust-laden air drawn into the first cyclone unit through a first air inlet, and a second cyclone unit that is formed inside the first cyclone unit, wherein the second cyclone unit includes a second cyclone body that has a second air inlet through which the air, from which the dust is separated by the first cyclone unit, enters the second cyclone body, and a guide unit that enables the air entering the second cyclone unit to be rotated.

Abstract: A dust collection unit for a vacuum cleaner includes a first dust collection part for filtering foreign objects in air, a second dust collection part for filtering foreign objects in the air that has passed through the first dust collection part, and a dust collection container having first and second dust collection chambers that correspond to the first and second dust collection parts, respectively. The first and second dust collection chambers store the foreign objects filtered by the respectively first and second dust collection parts in a state where parts of the respective first and second dust collection parts are received in the respective first and second dust collection chambers and the first and second dust collection chambers are provided in a line.

Abstract: There is provided a modularized hybrid dust collector for treating dust generated in various industrial processes. The box-shaped hybrid dust collector includes a first box-shaped dust collecting unit or a first cylindrical dust collecting unit, to which the inertial impaction and the principle of collecting dust using the centrifugal force are applied, and a second box-shaped dust collecting unit implemented by a dust collecting filter such that a problem of employing a cleaner and a limit of capacity, of a conventional cylindrical dust collector, can be overcome, and a high capacity modularized hybrid dust collector in which the box-shaped hybrid dust collector as a basic module and a plurality of dust collector modules are combined.

Abstract: Cyclone collector including a primary cyclone (1) having a first inlet (14) for drawing external air, and a first outlet (14) for discharging air, a secondary cyclone (3) connected to the primary cyclone (1), and flow guide means (200) over the first outlet for preventing a flow direction of the air discharged from the first outlet (14) from turning sharply.

Abstract: The invention relates to a system for separating a mixture of gas and liquid into a heavy fraction and a light fraction, the system comprising:—a separation vessel having a vessel inlet for the supply of the mixture to be separated, an upper vessel outlet for the discharge of the light fraction and a lower vessel outlet for the discharge of the heavy fraction;—at least one inlet device for pretreatment of the incoming mixture, the inlet device, comprising a casing having a liquid outlet for the discharge of a first mixture part mainly containing liquid to a lower compartment of the separation vessel; and at least one demister element arranged at a position below the liquid outlet for separating liquid from the gas in the first mixture part flowing from the liquid output.

Abstract: A cyclone dust collector is provided, including a cyclone unit that includes a first cyclone unit including a cyclone chamber to separate dust from dust-laden air, and a second cyclone unit, which is mounted in the first cyclone unit, including a plurality of cones to separate fine dust, and a cover unit that is formed on the cyclone unit to gather air discharged from the second cyclone unit and guide the air outside the cyclone dust collector, wherein the first cyclone unit includes a blocking plate at a lower part of the first cyclone unit, the blocking plate including a plurality of holes that are in fluid communication with the plurality of cones.

Abstract: A multi cyclone collector with an improved structure is disclosed for providing the highest number of second cyclone collector (300) by disposing a plurality of second cyclone collector (300) in a non circular shape (400) arrangement along a first cyclone collector, thereby increasing collecting efficiency.

Abstract: A fluid separator includes a side-by-side double-vortex fluid generator installed within a pressure vessel. The vortex generator separates the liquid and gas components of the incoming fluid mixture, and the vessel itself helps further separate the liquid into water and oil components, which makes the fluid separator particularly suited for processing fluids extracted from an oil well. The generator includes two diverging vortex tubes each having a polygonal cross-section. Such a cross-section allows the tubes to be formed using a conventional press brake. The vortex tubes also have diverging longitudinal centerlines to help spread the liquid flow pattern discharging into the vessel.

Abstract: An indoor vacuum cleaner comprises a dirty air inlet, a handle, a cyclone separator having an outer wall, a fluid inlet downstream from the dirty air inlet and a fluid outlet, a plate having a cyclone chamber surface and positioned to substantially divide the cyclone separator into a cyclone chamber and a dirt collection chamber, each of the cyclone chamber and the dirt collection chamber having an outer wall, the outer wall of each of the cyclone chamber and the dirt collection chamber having an outer perimeter, the dirt collection chamber having a cyclone chamber end spaced from a dirt collection floor, a passage extending between the cyclone chamber and the dirt collection chamber, the passage configured such that separated dirt travels at least outwardly as the dirt travels through the passage and, an air flow motor.

Abstract: A dual cyclone dust-collecting apparatus of a vacuum cleaner is disclosed. The dust-collecting apparatus includes an air inlet through which an external air is drawn in, two cyclone chambers into which the external air drawn in through the air inlet air is drawn in, the two cyclone chamber being disposed in parallel, at least one dust-collecting chamber divided in parallel with respect to the two cyclone chambers, and two air outlets through which the external air from the two cyclone chambers is discharged. The air inlet is formed between the two cyclone chambers at a lower part of a cyclone body and the two air outlets are formed in bottom surfaces of the two cyclone chambers, respectively, so that the external air is drawn in through lower parts of one sides of the two cyclone chambers and then discharged through the bottom surfaces of the two cyclone chambers.

Abstract: Cyclonic separating apparatus for a cleaning appliance such as a vacuum cleaner has a longitudinal axis, an upstream cyclonic separator and a downstream cyclone assembly. The downstream cyclone assembly comprises a plurality of cyclones arranged in parallel with one another. The downstream cyclones are arranged in a first set in which each cyclone has a longitudinal axis inclined at a first angle (?) to the longitudinal axis of the cyclonic separating apparatus and a second set, in which each cyclone has a longitudinal axis inclined at a second angle (?) to the longitudinal axis of the cyclonic separating apparatus. The second angle (?) is greater than the first angle (?). The invention allows the downstream cyclone assembly to be compactly packaged.

Abstract: A compact multi-cyclone dust separating is disclosed. The multi-cyclone dust separating apparatus includes a first cyclone chamber that separates dust-laden air drawn from outside, a second cyclone chamber that is disposed in the first cyclone chamber, and that separates dust-laden air drawn from the first cyclone chamber, and a third cyclone chamber that is disposed around a periphery of the first cyclone chamber, and that separates dust-laden air drawn from the second cyclone chamber.

Abstract: A dust collector cup working in the principle of fall centrifugal separation, consists of cup body (13), outlet (3) on the cup body (13), inlet (1) tangential to the circumferential wall of the cup body (13), and a separator settled in the cup body (13). The separator is composed of outlet tube (9), inlet (6) on the wall of the outlet tube (9), and the isolating shield (7) under the inlet (6) of the outlet tube (9), with the outlet tube (9) linked to the outlet (3) of the cup body (13). The fall between the horizontal positions of the lower end of inlet of the cup body (13) and the upper end of the inlet (6) of the outlet tube (9) is 0-140 mm.

Abstract: A surface cleaning apparatus comprises a dirt inlet, a handle, a cyclone separator having an outer wall, a fluid inlet downstream from the dirt air inlet and a fluid outlet, a plate having a cyclone chamber surface and positioned to substantially divide the cyclone separator into a cyclone chamber and a dirt collection chamber, the plate being removably mounted in the cyclone separator, a passage extending between the cyclone chamber and the dirt collection chamber and a fluid flow motor.

Abstract: Object of the present invention is to provide a dust collecting device (10) for a vacuum cleaner of which dust collecting performance is improved. The dust collecting device (100) of the present invention includes a primary cyclone unit (200) having two primary cyclones (210, 220), arranged in parallel, for separating dust by a cyclone principle, a secondary cyclone unit (300) having at least two secondary cyclones (310, 320), which receives air from the primary cyclones (210, 220) on an outer side of the primary cyclones (210, 220) for separating dust by the cyclone principle, and a dust container (110) having the primary cyclone unit (200) and the secondary cyclone unit (300) mounted thereto, and a primary dust collecting space for storing the dust separated at the primary cyclone unit (200), and at least one secondary dust collecting space for storing the dust separated at the secondary cyclone unit (300) formed therein.

Abstract: A surface cleaning apparatus comprises a dirt inlet, a handle, at least a first cleaning stage comprising a plurality of cyclones in parallel and a plurality of dirt collection chambers that are emptied concurrently wherein the plurality of cyclones and the plurality of dirt collection chambers are removable as a unit from the surface cleaning apparatus, and an air flow motor.

Abstract: A dust collecting apparatus for separating particles from an airflow comprises at least a first cyclonic separator for removing larger particles from the airflow and a plurality of second cyclonic separators, arranged in parallel and in tandem with one another, for removing smaller particles.

Abstract: The multi-cyclone dust separating apparatus includes a first cyclone unit including a first outer tub with a first air inlet and a cylindrical element with a first air outlet, and whirling air from the first air inlet to separate dust therefrom, the cylindrical element being disposed in the first outer tub to form a first cyclone chamber, along with the first outer tub; a second cyclone unit including a plurality of cyclones, each having a second air inlet for drawing in dust-laden air from the first cyclone chamber, to provide a second dust separation; and a dust bin including a first dust collecting chamber for collecting the dust separated by the first cyclone unit and a plurality of second dust collecting chambers for collecting the dust separated by the second cyclone unit.

Abstract: In order to provide an oil separator for separating oil from a blowby gas of a cylinder head of an internal combustion engine, which oil separator is manufactured separately from a basic body of a cylinder head cover but may nevertheless be easily integrated into the cylinder head cover, it is proposed that the oil separator comprises an oil separator module, which is manufactured separately from a basic body of a cylinder head cover and comprises a cyclone plate having at least one cyclone as well as a base plate, wherein the cyclone plate is fastened to the base plate and the oil separator module is fastenable to the basic body of the cylinder head cover.

Abstract: A surface cleaning apparatus comprises a dirt inlet, a handle, a cyclonic cleaning unit comprising a plurality of cyclones and at least one dirt collection chamber, each of the plurality of cyclones having an outer wall, an interior, a fluid inlet downstream from the dirt inlet and a fluid outlet, the at least one dirt collection chamber having an outer wall and an interior, wherein the surface cleaning apparatus is constructed such that the interior of the at least one dirt collection chamber is visible from a position exterior to the surface cleaning apparatus and a fluid flow motor. The surface cleaning apparatus may have a filter with a housing that is at least partially transparent.