Abstract: An air-cooled engine (10) is cooled by cooling air (Wi). The air-cooled engine (10) includes a cylinder block (33) and a cylinder head (28). The cylinder block (33) has cylinder cooling through-ducts (101, 102) capable of transmitting cooling air (Wi), on the periphery of a cylinder (26). The cylinder head (28) has a head-cooling through-duct (104) capable of transmitting cooling air (Wi). The cylinder-cooling ducts (101, 102) and the head-cooling duct (104) extend in a direction perpendicular to the axial line (109) of the cylinder (26), and are communicated with each other by means of communication channels (105, 105).

Abstract: A cooling air conduit for motorcycle engine which is particularly suitable for V-twin cylinders is provided which is constructed of a conduit body of elongated, tapered shape formed by a top panel, a bottom panel and two side panels such that a cool air passageway is formed inbetween the panels to direct cool air, away from the first cylinder, and onto the second or rear cylinder for efficient cooling.

Abstract: A full time lean air fuel mixture running spark ignited air cooled aircraft piston engine. In one embodiment, a drop-in substitution is provided for an equivalent make, model, and engine size, wherein the new, rebuilt, or reconfigured engine provides as much or more horsepower when compared to the original engine, but runs at a lean air fuel ratio condition during normal operating modes, including takeoff, climb, and cruise, thus saving significantly on fuel. In yet another embodiment, a drop-in substitution having a somewhat larger cylinder displacement volume may be provided to attain equivalent or enhanced maximum horsepower while operating at lean air fuel ratios. Enhanced engine life may be anticipated, since cylinder head temperatures (CHTs) may be reduced, compared to engines using rich air fuel ratios for climb and cruise conditions. Aircraft using such engines are also disclosed.

Abstract: An air-cooled engine (10) has a fan cover (16) for covering a cooling fan (14). The cover (16) is composed of a fan-cover peripheral wall (44) for covering the outside of the cooling fan (14), and a top board (45) for closing off one end of the fan-cover peripheral wall (44). The fan-cover peripheral wall (44) has an internally disposed guiding duct (47) for guiding cooling air (Wi) from the cooling fan (14) to an engine main body (12). A first fastening member (42) secures a portion of the external part of the fan-cover peripheral wall (44) that is proximal to the guiding duct (47) to a casing (25) of the engine main body (12). A second fastening member (41) extends from the casing (25) and through the fan-cover peripheral wall (44), and secures a top board (45) in a portion that is at a distance from the guiding duct (47).

Abstract: An engine and a generator driven by the engine are resiliently supported on a frame. A duct member is integrally attached to the engine and the generator to define a continuous cooling-air passage between the duct member and outer peripheral surfaces of the engine and the generator. A cooling fan is disposed on an inlet side of the cooling-air passage. A silencing plate is integrally attached to the duct member and faces an inlet of the cooling-air passage with a ventilation gap defined therebetween. The silencing plate has an area opposing the inlet that is larger than an opening area of the inlet.

Abstract: A system for protecting a crank angle sensor is disclosed. The system includes a protective member, a heat insulating member and an airflow deflecting member. The heat insulating member insulates against heat from adjacent heat sources. The airflow deflecting member directs driving wind into an interior portion of the protective member to cool the air adjacent to a portion of the crank angle sensor. The protective member also includes holes to receive the driving wind directed from the airflow deflecting member.

Abstract: In a cylinder head structure for an internal combustion engine that directs air into a covered space above the cylinder head covered by a head cover to ventilate the covered space, a gas flow passage space that extends continuously over an entire length or substantially over the entire length in a longitudinal direction is formed in the covered space. In addition, an air introduction position is provided within the gas flow passage space, and an air discharge position is provided outside the gas flow passage space.

Abstract: A heat exchanger suitable for a vehicle includes a plurality of tubular first members arranged in a row and forming elongate gaps. These members form passageways for flow of a first fluid for heat exchange with cooling air flowing through the gaps. The first members and gaps form a primary heat exchange area. Inlet and outlet manifolds are connected to the first members for directing the first fluid through the first members. An associated cooling device circulates liquid coolant and comprises flat tube-like second members, each extending into a respective gap in a secondary area which is part of the primary area but smaller. The second members each have a thickness at least the width of their respective gaps. At least some of the first members can be formed with cut-outs in opposite flat sides, these cut-outs being sealingly closed by the second members.

Abstract: The invention relates to a cooling system for a motor vehicle comprising a radiator (1) through which a coolant for, in particular, cooling an engine (2) flows, and which is flowed through by a cooling air flow (7) that is influenced by a fan (4) according to the velocity of the motor vehicle. Said fan is situated between the radiator (1) and the engine (2). The projection of the fan surface toward the radiator surface is smaller than the radiator surface by a difference area, whereby this difference area of the cooler surface is covered by a fan cowl (25). In order to create cooling system that is improved with regard to aerodynamics, the fan cowl (25) is provided with at least one opening (27) on at least one side of the difference area.

Abstract: A cooling structure of an internal combustion engine includes a cylinder block having a plurality of cylinder bores; a cylinder head disposed on an upper portion of the cylinder block; two camshafts disposed on the cylinder head so as to be juxtaposed to each other in parallel to a crankshaft; camshaft housing chambers formed on the cylinder head to house the respective camshafts; a recessed portion provided between the camshaft housing chambers; a plug seat formed between the camshafts and in the recessed portion; a cooling air passage formed between the cylinder bores; and cooling air introduction passages communicating from the cooling air passage to the recessed portion of the cylinder head.

Abstract: A blower housing for use with an engine. The blower housing is adapted to receive a stream of intake air, and the engine includes at least one cylinder. The blower housing includes an intake opening, an air filter housed within a filter compartment, and an air flow duct adjacent to the filter compartment. The air flow duct is configured to direct air to the at least one cylinder. The air flow duct includes a first surface and a second surface, the first surface being angled with respect to the second surface to deflect the air passing through the duct away from the first surface toward the second surface. The first surface separates the air into a first portion and a second portion having deflected particulate matter therein. The duct also has an aperture that allows air to flow from the duct to the air filter, and an exhaust window.

Abstract: In an engine-driven power generator, a fan-equipped flywheel and a drive shaft of a power generation section are connected to a crankshaft of an engine, and the power generation section is driven by the drive shaft being driven via the crankshaft. The fan-equipped flywheel is disposed between a crankcase of the engine and the power generation section, and small- and large-diameter cooling fans for cooling the engine and power generation section are provided on the fan-equipped flywheel.

Abstract: Engine-driven power generator includes: a power generation section having a drive shaft connected to a crankshaft; a gas-liquid separation unit provided upstream of the power generation section and having an air inlet port for taking in cooling air, the inlet port being disposed immediately under a fuel tank, the separation unit separating moisture from the taken-in air; and a cooling fan rotatable by the drive shaft to direct the taken-in air into the power generation section.

Abstract: An air cooling system includes an intake line, a heat exchanger, an exhaust line, and an amount of frozen carbon dioxide. The intake line connects the heat exchanger to an air source, and the exhaust line connects the heat exchanger to an air destination. The frozen carbon dioxide is disposed against at least a portion of the heat exchanger to draw heat away from the air. Optionally, a system can include dual heat exchangers connected via a bridge line, with the frozen carbon dioxide being disposed there between.

Abstract: There is provided an air-cooled engine (10) that is cooled by cooling air. The air-cooled engine (10) comprises a cylinder block (33), and a cylinder head (28) that closes off one end of a cylinder (26). The cylinder head (28) includes a base part (81) that is superposed on and secured to the cylinder block (33) by a plurality of bolts (91), and a valve compartment (83) formed integrally on the base part (81). All of the bolts (91) are disposed near the outer periphery of the base part (81) at positions outside of the valve compartment (83).

Abstract: A starting module assembly of a remote control car includes an engine mount and a starter. A seat cover and a fixed base are installed outside the engine mount. A transmission gear cylinder is installed between assembling holes of the seat cover and the fixed base. An actuation gear is engaged between two transmission gear cylinders and sheathed into a spindle bearing of the engine mount for switching the direction of directly installing the engine mount. The starter has a penetrating ventilation hole at the front end of the upper half portion for dissipating heat produced by the electric motor. An external cover for fixing the rechargeable battery is pivotally coupled for preventing the external cover from being separated or fallen off when the cover is lifted. Further, a space is reserved at the front end of the upper half portion for installing an electric motor of different sizes.

Abstract: A drive system for a tool, particularly a chain saw, includes a fresh air inlet and an intake manifold arranged after the fresh air inlet in the flow direction of the fresh air that opens into a carburettor. A combustion engine is provided that is arranged after the carburettor in the flow direction of an air-fuel mixture produced in the carburettor, in which the carburettor is exposed to a lower level of thermal stress. At least one heat conducting cooling vane is connected to the carburettor and protrudes outwards into direct contact with the ambient fresh air.

Abstract: A V-twin engine having a crankcase and a pair of cylinders defining a V-space therebetween, wherein the V-space is substantially enclosed, and a carburetor is positioned within the V-space. An intake air preheating arrangement supplies heated intake air to the carburetor, and a carburetor heating arrangement heats the V-space and the carburetor which is positioned within the V-space. Each of the foregoing arrangements, used separately or in combination within one another, aids in preventing “freeze-up” of the carburetor during running of the engine in a cold environment.

Abstract: An engine with expansion piston located on the end of a motion arm connected to the engine shaft. On the shaft, rotating compression pistons are mounted. The distance between the two piston types allows for the production of great torque. The geometry of expansion chamber and compression chamber is concentric toroidal. A pressure chamber stores the air-fuel mixture coming from the compression chamber to the expansion chamber and is therefore interposed between the two. The timing of the two or more sliding ports attached to the compression chambers determines the compression volume, while the valves control the communication of the pressure chamber with the other chambers.

Abstract: A forced-air-cooled engine has a main blow-out opening provided to a back plate of a cooling fan cover at a position facing a cylinder part for blowing out cooling air for cooling a cylinder part and a secondary blow-out opening provided to the back plate at a position opposite to the main blow-out opening in regard to the crankshaft center for cooling a part of a crankcase part, wherein a cooling air guide cover is equipped which is composed of a cylinder air-guide cover part which guides air blown out from the main blow-out opening to flow to cool the cylinder part and cylinder head, and a top cover part which guides air blown out from the secondary blow-out opening to flow along a side face of the crankcase part to cool there and then flow into midstream of the cooling air flow blown out from the main blow-out opening and cooling the cylinder part and cylinder head.

Abstract: A system for cooling a power source enclosure may include a power source enclosure configured to substantially enclose a power source, and a cooling package, including an airflow provider, located separately from the power source enclosure. The system may further include a conduit configured to provide a fluid connection between a section of the airflow provider and an area inside the power source enclosure, wherein the conduit includes a first end disposed near the section of the airflow provider, such that during operation of the airflow provider a pressure differential exists between the first end and a second end, and wherein the second end is disposed near and in fluid communication with an area within the power source enclosure.

Abstract: A charge air cooler comprises at least one tubular element with an internal flow duct for guiding compressed air, and a tank for receiving the compressed air before it is led through the flow duct. The compressed air is cooled by a first cooling medium of ambient air as it passes through the flow duct. A cooling element at least partly situated inside the tank provides the compressed air in the tank with a first step of cooling before the air is led to the flow duct wherein the air undergoes a second step of cooling.

Abstract: An internal combustion engine includes a cylinder wall through which an exhaust port with an exhaust port inner surface is routed from a combustion chamber to an exhaust port opening in the cylinder wall. A pipe section is arranged in a section of the exhaust port following the exhaust port opening in the direction of the combustion chamber with a pipe section outer surface, which reduces the heat transfer from the exhaust gas from the exhaust port into the cylinder wall. The pipe section outer surface is spaced from the exhaust port inner surface through an air gap by sections along an entire outer circumference of the pipe section.

Abstract: A drive system for a tool, particularly a chain saw, includes a fresh air inlet and an intake manifold arranged after the fresh air inlet in the flow direction of the fresh air that opens into a carburettor. A combustion engine is provided that is arranged after the carburettor in the flow direction of an air-fuel mixture produced in the carburettor, in which the carburettor is exposed to a lower level of thermal stress. At least one heat conducting cooling vane is connected to the carburettor and protrudes outwards into direct contact with the ambient fresh air.

Abstract: An air cleaner for a portable engine, includes an air cleaner case attached to an upper part of an engine body of the engine. Preferably, the air cleaner case is supported on an upper wall of a shroud covering the engine. Preferably, the air cleaner case is formed integrally with the shroud. Preferably, the air cleaner further includes an air intake structure divided into a plurality of intake passages having inlets displaced relative to each other with respect to an air flow direction in which an intake air flows.

Abstract: The present invention provides an intake port design that provides a low thermal inertia characteristic, thereby decoupling the surface temperature of the intake port walls from that of the coolant through use of an air gap formed between the intake port and the cylinder head. At idle and part-throttle, the intake port is at a higher surface temperature yielding better cold-start emissions, better mixture preparation, and less dense intake charge (“thermal throttling”) for better fuel economy. At wide-open-throttle, the intake port is at a lower surface temperature yielding better volumetric efficiency for improved torque and reduction in knocking tendency enabling higher compression ratio for improved fuel economy and performance. The intake port design of the present invention can be manufactured with a hydroform manufacturing process resulting in improved dimensional consistency and smooth surface finish. Additionally, the process eliminates some cylinder head machining processes.

Abstract: A motorcycle can include an air cleaner in communication with intake ports of its engine, and a wind introduction duct for introducing a wind into a primary chamber of the air cleaner. The wind introduction duct can extend from an outside air introduction port located forwardly from the intake port, passing by the front and rear intake ports and extending to the primary chamber of the air cleaner.

Abstract: The invention relates to a circuit arrangement (K) comprising a low-temperature circuit (NK) for cooling charge air (13) that is fed to a motor (8) in a motor vehicle equipped with a turbocharger. According to the invention, the charge air (13) is compressed in two stages in a first low-pressure turbocharger (1) and a second high-pressure turbocharger (2). To cool the charge air (13) a first cooler (3) is provided downstream of the low-pressure turbocharger (1) and upstream of the high-pressure turbocharger (2) and a second cooler (4) is provided downstream of the high-pressure turbocharger (2) and upstream of the motor (8). The invention also relates to a method for operating a circuit arrangement (K) of this type.

Abstract: A V-twin engine having a crankcase and a pair of cylinders defining a V-space therebetween, wherein the V-space is substantially enclosed, and a carburetor is positioned within the V-space. An intake air preheating arrangement supplies heated intake air to the carburetor, and a carburetor heating arrangement heats the V-space and the carburetor which is positioned within the V-space. Each of the foregoing arrangements, used separately or in combination within one another, aids in preventing “freeze-up” of the carburetor during running of the engine in a cold environment.

Abstract: A straddle-type vehicle is provided with an engine unit and an engine air-intake system. The engine unit includes a cylinder head provided with an air-intake port communicating with a combustion chamber, the air-intake port being provided with a valve seat disposed to an opening of the combustion chamber. The engine air-intake system includes a throttle body connected to an upstream side of the air-intake port and an air cleaner connected to an upstream side of the throttle body via an air-intake pipe so as that the air cleaner projects upward over the upper frames, the air cleaner having an inner clean section, and an axis connecting the clean section and the throttle body extends linearly toward the valve seat.

Abstract: The invention relates to a portable handheld work apparatus including a chain saw, a vacuum/blower apparatus or the like. The work apparatus has a handle (2) for carrying and guiding the work apparatus (1). Thumb supports (4, 5) are provided on both sides with respect to the longitudinal axis (3) of the handle (2).

Abstract: An air cleaner device for a vehicle is provided with an air cleaner body containing an air cleaner element and a snorkel connected to the air cleaner body to introduce the outside air into the air cleaner body. The snorkel extends forward of the vehicle past a side of a cylinder portion which projects upward from an engine, and a front end of the snorkel opens between right and left seats of the vehicle. With this configuration, even if the air cleaner body of the air cleaner device should be flooded, it is difficult for water to enter into the interior. Further, it is difficult for the air cleaner body to be influenced by heat, and difficult for dust to get into the air cleaner body.

Abstract: A power supply device for a vehicle, for driving a motor which is mounted on a vehicle and makes the vehicle travel. The power supply device for a vehicle includes: a battery unit having a plurality of secondary batteries; a battery temperature sensor for detecting the temperature of a secondary battery; a heat insulating mechanism for controlling the temperature of the secondary battery; an outside air temperature sensor for detecting the temperature of air outside of the vehicle; an air intake port for taking the outside air to the battery unit in the vehicle; an intake valve for opening/closing the intake port; and a temperature controller for controlling the opening/closing of the intake valve on the basis of the temperature difference between the outside air temperature detected by the outside air temperature sensor and the battery temperature detected by the battery temperature sensor.

Abstract: An engine-driven work machine enables the work machine and its electrical components to be properly cooled. An engine-driven work machine comprises an engine, a work machine driven by an engine, and electrical components belonging to the work machine, and supplies an output for work while being driven by the engine; the engine-driven work machine has an open machine accommodating section, which is provided in a main body of the work machine and accommodates an engine and a work machine driven by the engine, and a control box for accommodating part of the engine, electrical components of the work machine, and a fuel tank; the control box is provided above the machine accommodating section, and has a ventilation path that connects to a fan fitted to the engine, the electrical components and the fuel tank being arranged along the ventilation path.

Abstract: The invention involves a vehicle with a cab. The environment of the cab may be maintained by a heating, ventilation, and air-conditioning (HVAC) system that will provide cool air to the cab in hot weather and warm air to the cab in colder weather. The HVAC system will have its own specific air heating and cooling components. The HVAC has a supply to the cab for providing the cool or warm air depending on the need. A siphon or alternative point of distribution of the HVAC output may be a HVAC diversion line that leads into the inlet of the turbocharger or supercharger of the vehicle engine to mix with ambient air entering the turbocharger. In an alternative embodiment, a compressed air source may be bled into the turbocharger or supercharger inlet.

Abstract: A cooling air path is formed by an air duct provided in front of an engine and below main frames. The air duct has a cooling air port that is almost the same width, in plan view, as the lateral width of the main frames and a discharge port is formed thinner than the cooling air port, further to the rear than the cooling air port and in the vicinity of the engine.

Abstract: A power tool including a main section and a handle section. The main section includes an internal combustion engine and a housing at least partially surrounding the engine. The engine includes a cylinder, a spark plug, and a muffler. The handle shaft extending from the main section. The shaft forms a handle for the power tool and houses a drive shaft from the engine therein. The housing forms a cover section over a transmission assembly between the engine and the drive shaft. The cover section includes a scroll form to channel air flow pushed by the transmission assembly. The housing further comprises a spark plug boot to substantially prevent air from exiting the housing at the spark plug.

Abstract: A construction machine of the present invention is provided, in a compartment formed by a cover, with an engine, a centrifugal fan, and a heat exchanger for exchanging heat between cooling air blown by the centrifugal fan and a specified medium, wherein the centrifugal fan and the heat exchanger are arranged further upstream than the engine with respect to flow of cooling air, so that cooling air sucked in by the centrifugal fan is led to the engine after passing through the heat exchanger.

Abstract: To provide a small-size engine having a forced air cooling system, wherein the amount of protrusion of the air intake system outwardly from the engine body can be minimized and the limitation on the space required for installation of the engine to the various work units can be alleviated, the engine includes a cooling fan (9) mounted on one end of a crankshaft (4) and has a longitudinal axis (S) of a cylinder block (5) inclined relative to a horizontal direction and also to a vertical direction. A fan housing (17) for guiding a cooling air (W) from the cooling fan (9) towards a cylinder block (5) and a cylinder head (6) is formed with a cutout (22) through which a float chamber (23) of a carburetor (15) is positioned inside the fan housing (17).

Abstract: The present invention provides a fan installation for a cooling system of a motor vehicle, comprising at least two fans which respectively have an electric fan motor arranged in a separate housing and a fan wheel which can be driven by the fan motor. The fan installation also comprises a control unit for operating the fan motors. The invention provides for an improved fan installation with a simple and cost-effective design, which is achieved by arranging the control unit in the housing of one of the fans for operating both fan motors.

Abstract: A four-stroke internal combustion engine is provided that is capable of use in many power tools, including those power tools subjected to tippable applications. There is provided within an engine housing an oil reservoir and a valve chamber which independently communicate with a crank chamber. A strategically placed divider and passageway, located within the engine housing, appropriately direct lubricant within the engine housing so that the internal cavity of the engine is lubricated during use in various operating attitudes, and so that the fluid flows to and is held in the proper chambers of the engine housing during storage. There is also provided a breather arrangement for an internal combustion engine which includes a cam shaft having a hollow passageway in communication with the crank chamber and the air intake system of the engine.

Abstract: Engine cooling system and method for making same wherein an engine, engine casing, or component thereof or a component related thereto has at least one cooling fin (18) having at least a portion of an edge surface (32) including an engraved, or intagliated portion (40). Preferably the surface edge includes a plurality of itagliated portions (40) with each portion including at least two elongated concavities being in preselected orientation and relationship to each other to improve the cooling efficiency of the fin and thus allow the engine to operate in wider, more extreme range of temperatures and environments. The present invention is particularly well suited, but not limited to air-cooled engines and related components such as component covers, inspection/access covers, and oil coolers and is therefore readily adaptable to engines used to propel motor vehicles such as, but not limited to, motorcycles.

Abstract: A power tool including a main section and a handle section. The main section includes an internal combustion engine and a housing at least partially surrounding the engine. The engine includes a cylinder, a spark plug, and a muffler. The handle shaft extending from the main section. The shaft forms a handle for the power tool and houses a drive shaft from the engine therein. The housing forms a cover section over a transmission assembly between the engine and the drive shaft. The cover section includes a scroll form to channel air flow pushed by the transmission assembly. The housing further comprises a spark plug boot to substantially prevent air from exiting the housing at the spark plug.

Abstract: An implement is provided having a motor housing in which is disposed an internal combustion engine as a drive for a tool. The implement also includes a carburetor and an air filter. An air filter chamber is provided with a cover element that includes two cover portions, a first cover portion of which extends over the air filter chamber, and a second cover portion of which extends over a ventilated hollow space of the motor housing that is adjacent to the air filter chamber. At least one in-flow passage for the combustion air is provided and in the first cover portion opens into the air filter chamber. At least one further passage is provided for connecting the hollow space with the in-flow passage.

Abstract: A motor vehicle with a forward-mounted engine and a forward-situated air intake has a tubular chassis element running in the longitudinal direction of the vehicle. Between the air intake and the chassis element there is a guide arrangement for leading air into and through the chassis element past at least one major vehicle component, advantageously the vehicle's gearbox, situated inside the chassis element. Downstream from that major vehicle component there is an air outlet.

Abstract: A cooling system for an internal combustion engine with two-stage supercharging includes a charge-air line in which is provided a first compressor of a first turbocharger and a second compressor of a second turbocharger downstream of the former, a first charge-air cooler being provided between first and second compressor, and a second charge-air cooler downstream of the second compressor. At least one of the two charge-air coolers is disposed upstream of the coolant cooler as seen in a flow direction of the cooling air, and the second charge-air cooler is disposed above or beside the first charge-air cooler.

Abstract: To cool a power drive unit for controlling the operation of a motor-generator connected to an engine and function as either a motor or a generator, an electric power drive unit-accommodating chamber is defined outside a side frame disposed on a side of an engine room with the engine accommodated therein in a widthwise direction of a vehicle, and is separated from the engine room. The electric power drive unit is accommodated in the power drive unit-accommodating chamber. A cooling device is integrally provided on the electric power drive unit to use cooling water to perform heat exchange with travel wind, and a heat shield plate is mounted between the engine room and the electric power drive unit-accommodating chamber.

Abstract: A blower housing is coupleable to an engine including a cooling fan that is rotatable about an axis. The blower housing includes a first housing portion that is coupled to the engine and has an intake opening through which air may flow. The blower housing also includes a removable housing portion that is removably coupled to the first housing portion and has first and second sidewalls that direct air toward at least one engine cylinder. In one embodiment, the first and second sidewalls direct air toward different engine cylinders, in another embodiment, the first and second sidewalls direct air toward the same engine cylinder.

Abstract: A portable power working machine (10) is disclosed, which is capable of effectively improving the performance thereof to cool the internal combustion engine (20), and also capable of preventing an air cleaner (30) of the air intake system of the internal combustion engine (20) from being clogged with dust. This portable power working machine is characteristic in that it comprises a guiding wall (28) disposed on one side of a main housing (12) and at a location rear to a cooling fan (25) and projected inward therefrom for guiding cooling air toward the cylinder (21) of the internal combustion engine (20); an intake passageway (50) formed at a location rear to the cooling fan (25) for introducing air into an air-intake system (30, 34, 35) of the internal combustion engine (20); and an air-intake port (55) for the intake passageway (50), the air-intake port (55) being positioned in the vicinity of a root portion (28a) of the rear face of the guiding wall (28).

Abstract: The cleaning arrangement (1) is provided for the combustion air (2) of an internal combustion engine (3) in a portable handheld work apparatus such as a cutoff machine. The cleaning arrangement is formed from a filter housing (4) which contains an air filter (5) in order to ensure a disturbance-free operation especially for a dust-laden ambient air of the work apparatus. The air filter (5) partitions the filter housing (4) into a contaminant space (7) and a clean space (8). The clean space side (8) is connected to a carburetor (9) of the engine (3). To minimize the dust deposit on the contaminant space side of the air filter (5), a centrifugal-force separator (11) is arranged in the filter housing (4) and is charged with combustion air (2) which is supplied under pressure by a cooling air fan (30) via a feed channel (24) to the separator (11).