Abstract: Ventilation devices, in particular for electric motor drives regularly comprise a fan wheel (1), which is driven by a shaft via an electromagnetic induction coupling. In order to reduce the complexity of manufacture, a stack of magnetic sheets (2) is cast in the aluminum hub of the fan wheel (1). Thus, aluminum also assumes at the same time the function of a damper winding.

Abstract: The invention relates to a cooling fan for use in a motor vehicle. To achieve improved cooling of an electric motor it is proposed that the motor housing enclosing the electric motor be used as a heat sink for emitting waste heat into a cooling air flow. The cooling air flow for cooling the electric motor is routed here through the interior of the motor housing and subsequently along the outside of the motor housing over cooling elements in the areas of the air inlet openings and in the area or an air exit gap between fan wheel hub and front part of the motor housing. The cooling air flow is created in this case by the fan wheel hub of the fan wheel driven by the electric motor.

Abstract: An outer-rotor type brushless fan motor is provided, wherein the outer edge of a stator of the outer-rotor type brushless fan motor is surrounded in the cup-shaped outer periphery of a rotor case of a rotor thereof, and the rotor is rotated with respect to the stator. The outer-rotor type brushless fan motor is characterized in that at least one projection and a corresponding opening thereof are formed on a surface of the rotor case, so that the projection and the corresponding opening thereof are rotated together with the rotation of the rotor, thereby heat generated by the stator is dissipated.

Abstract: In an electric compressor, in which an electric motor and a compressor driven thereby are integrated, in order to prevent a reduction in the durability of the electric motor and the like due to heat conducted from heat radiating bodies such as drive circuits, a fluid, prior to being taken into the compressor portion, is circulated through the electric motor portion as a medium for cooling. In this case, a plurality of cooling medium passages for example are provided parallel to the axis of rotation, and the endothermic capacity of passages formed in the vicinity of heat radiating bodies is made greater than the endothermic capacity of passages formed in other portions.

Abstract: A rotor assembly includes a housing and a hub. The housing has an open end and an opposed closed end, and is formed with a raised portion in the central location of the closed end. The hub is mounted on the closed end of the housing and covers the housing except for the raised portion to construct a thin motor.

Abstract: A fan 30 for mounting at one end of the armature of an electric motor comprises a ring portion 40 of moulded thermoplastic material supporting an annular plate 42 with integrally formed fan blades 46 in axial alignment with exhaust vents formed in the housing of the motor. The fan blades 46 extend radially across a face of the annular plate 42 remote from the ring portion 40 and extend into the annulus of the plate. The blades 46 are grouped and centered on the winding tunnels of the armature with the axially outer edges of the blades of each group joined together by a radial wall 50 within the radial spacing of the annulus of the plate 42 but axially spaced therefrom.

Abstract: An electrical generator (80) utilizes supplemental blowers or fans (140) to move additional cooling fluid through coolant flow paths (116, 124) in the generator, thus reducing the internal temperature of the generator. The supplemental blower comprises a blower (160) for supplementing cooling fluid flow through a discharge coolant flow path (155) and/or a supplemental blower (176, 178) for supplementing cooling fluid flow through an inlet coolant flow path (156). Either supplemental blower has the effect of lowering the peak internal generator temperature (134).

Abstract: An electric motor having a reverse air flow cooling system that eliminates the need to extend lead wires past the fan. The electric motor includes a fan positioned on the lead-end of the motor to move air through a housing of the electric motor in a direction generally defined from the shaft-end of the motor to the lead-end of the motor. Lead wires can extend from the stator windings radially through the housing for connection to an electric start switch. The electric start switch can be positioned in a control box that is coupled to the housing. The electric start switch can be operable to remove an auxiliary circuit from a stator circuit after startup of the electric motor.

Abstract: A sliding means with built-in moving-magnet linear motor is provided, realizing high-speed operation and much response ability of a table to a stationary bed, and also accurate position control of the table to the bed. With the sliding means of this invention, armature windings carry a three-phase current while a driving circuit is transferred to the external driver to make the bed slim in construction. Thus, the sliding means is reduced in overall height. A field magnet of rare earth permanent magnet is effective in raising flux density, thereby providing high propulsion for the table. An encoder to monitor a position of the table is an optical encoder having an optical linear scale, which contributes to improvement in accurate monitoring. The construction in which the armature windings connected to cords, lines, and so on are placed on the stator side has no fear of causing dust and dirt, thus realizing clean environment.

Abstract: A fan for an electrical machine having discrete fan blades mounted for rotation with the machine rotor. Each blade has a unitary mounting plate and is secured to the machine rotor or to a carrier on the rotor shaft. The preferred blade has a concave surface facing axially of the rotor in one direction and a convex surface facing axially of the rotor in the other direction. The concave/convex surfaces are formed by two flat triangular surfaces joined along a common edge. The triangular structure is fatigue resistant, reducing, the likelihood of mechanical failure.

Abstract: A miniature PMDC motor has a wound rotor 15 comprising a rotor core 16 and a commutator 17 mounted on a shaft 14. A cooling fan 20 is directly mounted onto the commutator 17 by use of a mechanical snap-fit type connection. Projections 29 on the commutator mate with recesses in the fan 20 to prevent relative rotational movement and detents including resilient fingers 23 and projection surfaces 34 hold the fan axially.

Abstract: In a vehicle alternator having a stator, a rotor, and frames, a disc group is fixed to an axial end surface of a magnetic pole core of the rotor for creating the flow of cooling air. The disc group includes a plurality of discs layered with gaps between them. The disc group is disposed rotatable with the rotor. When the disc group rotates with the rotor, cooling air flows in a radially outward direction along the disc surfaces.

Abstract: A rotating electric machine comprising at least a fan (43) provided with blades providing between them divergent ventilation channels (48) adapted to generate cooling fluid flow through the machine; the angle of incidence (B) of the blades, at the leading edge ranges between 150 degrees and 175 degrees, while the angle of incidence (A) of the blades at the trailing edge ranges between 90 degrees and 165 degrees relative to the tangent to a circle (C) generated during the rotation of the blades, the ratio between the average pitch of the blades (46) and the average length thereof being less than 0.975. The invention is applicable to fans for a motor vehicle alternator.

Abstract: In the case of an electrical machine, in particular an alternator for a motor vehicle, having a housing (2), a rotor (6) that is supported in the housing (2) in a manner that allows it to rotate around an axis of rotation (5) and that has at least one rotor winding (14) and at least one fan wheel (21) mounted on the rotor (6) for generating convection in the housing (2) and for dissipating heat from the at least one rotor winding (14), the at least one fan wheel (21) is joined with the rotor (6) at least in a linear manner in order to better cool the rotor (6).

Abstract: An electric hand tool is described that includes a machine housing (1) with an electric motor (12) accommodated in the machine housing (11) for driving a tool (13), and a fan wheel (21) accommodated in the machine housing (11) for generating a cooling air current that flows through the machine housing (11), which said fan wheel creates a suction space (22) and a pressure space (23) on opposite sides when it rotates. To increase the performance of the electric hand tool with longer idle periods for the machine components, purposeful cooling is carried out by providing means for generating an additional air current, which said means are configured such that the additional air current flows to machine components that are located outside of or in a low-flow region of the cooling air current.

Abstract: It is an object of the present teachings to provide a technique that rationalizes the structure of the brushless motor so as to save space in the power tool. According to the present teachings, a representative brushless motor utilized in a power tool may comprise a stator, a rotor and a cooling fan. The brushless motor is disposed within the power tool. The brushless motor is adapted to supply driving current to the stator to drive a tool bit of the power tool by rotating the rotor. The cooling fan is molded of a magnetic or conductive material so that the cooling fan also serves as a rotating position detector that detects the rotating position of the rotor with respect to the stator. Because the cooling fan may also have a function of rotating position detector of the rotor, the inner space of the power tool can be rationalized.

Abstract: An electrical machine has a stator, a rotor, and radially extending coolant passageways provided in a laminated core section of at least the stator. The coolant passageways are defined between axially spaced stacks of laminations in the laminated core section. The radial passageways are connected to coolant supply ducts through a gap between the stator and the rotor. More efficient cooling of the machine is obtained by providing a matrix of coolant duct sections extending circumferentially and axially of the core section. The matrix has first and second radially spaced apart faces respectively in fluid communication with the radially extending coolant passageways in the laminated core section and coolant exhaust ducts.

Abstract: A magneto generator including: a magnet rotor having a cup-shaped rotor yoke formed with a plurality of air vents in a bottom wall and a permanent magnet secured to an inner periphery of a peripheral wall of the rotor yoke; and an armature having an armature coil, wherein a cooling air introducing portion is provided for each of the plurality of air vents, a cooling air introducing passage for introducing cooling air into a corresponding air vent is formed inside the cooling air introducing portion, the cooling air introducing passage has a rectangular section, and opens in a sloping direction with respect to the direction orthogonal to a plane including both a straight line between the center of the bottom wall and the center of the air vent, and a central axis of the magnet rotor.

Abstract: A method is performed for attaching a fan to a rotor assembly for a dynamounted electric machine. A shaft is mounted within a housing of the dynamo-electric machine. The shaft includes an integral shoulder portion for creating an abutment surface. A fan which includes a fan base and a plurality of fan blades protruding from the fan base is mounted on the shaft. The fan base has a central bore wherein an inner circumference of the fan base along the central bore is juxtaposed to the abutment surface. A pair of pole cores is mounted axially along the shaft toward the shoulder portion so as to clamp the fan between a respective end of the pole cores and the abutment surface.

Abstract: A ring-like rib 19 is erected on an inner circumferential edge of an insertion hole 11, which is opened in the scroll casing 1 so that the fan f is inserted therethrough, while a side wall 18 facing the ring-like rib 19 is provided in the bracket 15 blocking the insertion hole 11. A helical groove portion 20 and a protruding portion 21 are formed in one of an outer surface of the side wall 18 and an inner surface of the ring-like rib 19 and in the other thereof, respectively. The bracket 15 is caught in the scroll casing 1 by turning the bracket 15 in a direction opposite to a direction of rotation of said fan f. Further, during the engagement therebetween, a cooling duct 4 is formed.

Abstract: An improved generator fan serves to draw air into the generator through an inlet in the generator housing, pass the air through the rotor and stator, and direct the air out openings in the generator housing. The fan of the present invention includes a disc and at least one multi-directional blade extending from the disc. The multi-direction blade includes a leading segment extending from the disc between a first radius measured from the axis of rotation and a second radius, the leading segment including a leading edge extending from the disc at an angle of about ninety degrees from the disc, the leading segment extending from the disc with an increasing angle along the length of the leading segment; and a trailing segment extending from the disc between the second radius and a third radius measured from the axis of rotation, the third radius being greater than the second radius and the trailing segment extending from the disc with an angle having a rate of change different than the leading segment.

Abstract: A heat-radiating structure for ceiling fan's motor housing, on the upper and the lower surfaces of a motor housing is provided with arched ears, each ear is provided with a ventilation orifice for sucking outside in and blowing it out; on the periphery of the motor housing is defined with inclined flow deflectors for introducing outside air in and expelling it out, with these structures, the motor housing itself is possess with an ability of heat-radiating.

Abstract: A method is performed for attaching a fan to a rotor assembly for a dynamo-electric machine. A shaft is mounted within a housing of the dynamo-electric machine. The shaft includes an integral shoulder portion for creating an abutment surface. A fan which includes a fan base and a plurality of fan blades protruding from the fan base is mounted on the shaft. The fan base has a central bore wherein an inner circumference of the fan base along the central bore is juxtaposed to the abutment surface. A pair of pole cores is mounted axially along the shaft toward the shoulder portion so as to clamp the fan between a respective end of the pole cores and the abutment surface.

Abstract: A rotating machine which includes a stator having a number of field winding slots, a number of field windings disposed in each of the field winding slots, at least two of the field windings have an outer jacket; and a number of conductive wires disposed within and enclosed by the outer jacket such that longitudinal passages are defined between the conductive wires. A pump circulates a coolant into and from the rotating machine through the longitudinal passages. Preferably, the rotating machine includes a housing that has a cavity for acceptance of the stator therein. The housing and stator define and second plenums at first and second ends of the stator. The coolant enters the rotating machine into the first plenum and exits the rotating machine from the second plenum.

Abstract: The invention relates to a rotating electric machine, especially an alternator or alternator/starter for motor vehicles, including a stator surrounding a rotor (10) equipped with a pack of metal plates, a gap between the stator and the rotor, permanent magnets integrated into the rotor and excitation coils (14) integrated into the rotor, in which the excitation coils are wound around salient poles (1310) cut out in the pack of metal plates of the rotor, and the permanent magnets are accommodated in housings (13110) formed in the pack of plates of the rotor and open towards the periphery of the rotor, characterized in that the housings (13110) are closed axially at each of their ends by a non-magnetic retaining piece (13) equipped with a part intended to come into abutment with the magnets, and in that the retaining piece features recesses for accommodations [sic] of the buns of the excitation coils (14).

Abstract: A fan with improved self-cooling capability having a frame, a stator, a magnetic ring, an iron case, and a rotor blade impeller. The frame has a base for containing the stator, and the stator is provided with at least a coil. The magnetic ring is magnetically coupled to the stator, and the iron case is coupled to the magnetic ring while being provided with at least a first heat dissipation hole. The rotor blade impeller is formed on the iron case, in which at least a second heat dissipation hole aligned to the first heat dissipation hole is formed on a hub of the rotor blade impeller, and the first heat dissipation hole and the second heat dissipation hole are not formed to directly align to a position of the coil.

Abstract: An improved generator fan serves to draw air into the generator through an inlet in the generator housing, pass the air through the rotor and stator, and direct the air out openings in the generator housing. The fan of the present invention includes a disc and at least one multi-directional blade extending from the disc. The multi-direction blade includes a leading segment extending from the disc between a first radius measured from the axis of rotation and a second radius, the leading segment including a leading edge extending from the disc at an angle of about ninety degrees from the disc, the leading segment extending from the disc with an increasing angle along the length of the leading segment; and a trailing segment extending from the disc between the second radius and a third radius measured from the axis of rotation, the third radius being greater than the second radius and the trailing segment extending from the disc with an angle having a rate of change different than the leading segment.

Abstract: A cooling fan structure comprises a base in which a ring stator is mounted. The ring stator is provided with polar claws which are bent to form in the inner side of the ring stator. A plurality of blades are pivotally mounted in a receiving space of the ring stator such that the blades are circumvented by a connection ring. A magnetic ring rotor is fastened with the connection ring and is induced by a coil of the ring stator to drive the blades, thereby improving the driving torque, the ventilation area, and the winding.

Abstract: In a vehicle alternator having a stator, a rotor, and frames, a disc group is fixed to an axial end surface of a magnetic pole core of the rotor for creating the flow of cooling air. The disc group includes a plurality of discs layered with gaps between them. The disc group is disposed rotatable with the rotor. When the disc group rotates with the rotor, cooling air flows in a radially outward direction along the disc surfaces.

Abstract: In the case of an electrical machine, in particular an alternator for a motor vehicle, having a housing (2), a rotor (6) that is supported in the housing (2) in a manner that allows it to rotate around an axis of rotation (5) and that has at least one rotor winding (14) and at least one fan wheel (21) mounted on the rotor (6) for generating convection in the housing (2) and for dissipating heat from the at least one rotor winding (14), the at least one fan wheel (21) is joined with the rotor (6) at least in a linear manner in order to better cool the rotor (6).

Abstract: Disclosed is an outer rotor type induction motor. The present invention includes a driving shaft, a stator core fixed to a frame and having a plurality of stator slots so that the driving shaft penetrates a center of the stator core, a coil wound on the stator slots so as to form a rotatory magnetic field, a rotor housing installed outside the stator core so as to maintain a predetermined slit with the stator core wherein the driving shaft is coupled through a bottom center of the rotor housing, a rotor conductor coupled with an inner circumference face of the rotor housing so as to generate a torque by the rotatory magnetic field of the coil, and a plurality of upper blades installed at an upper end of the rotor housing so as to leave a predetermined interval therebetween wherein an external air is forcibly sucked in to cool the coil when the rotor housing revolves.

Abstract: A method for forming an electric motor includes providing a stator and an armature having a lamination stack with slots therein in which magnet wires are wound. Thermally conductive plastic is molded over at least a portion of the armature to at least partially encase the magnet wires and to mold a fan. The fan is molded without any portion of the fan extending into the slots in the lamination stack of the armature to increase the volume in the slots in which the magnet wires can be wound and the magnet wires are wound in this increased volume when they are wound in the slots in the lamination stack to increase a power rating of the electric motor beyond what is normally attainable with a fan component having portions extending into the slots in the lamination stack.

Abstract: In an alternator having a vacuum pump capable of improving a cooling characteristic, and having a rotary shaft supported by bearings installed in a rear bracket of the alternator, a housing of the vacuum pump has vanes and a rotation rotor is installed on the rotary shaft. A pump bracket is assembled to a lower portion of the housing and includes a packing inserted in an outer circumferential portion of a center shaft hole of the pump bracket for implementing a sealing operation in surface-contact with the rear bracket. A certain space is formed between the packing and the shaft hole for preventing a heat transfer, and a heat radiating unit is installed in a lower surface of the pump bracket.

Abstract: An improved vacuum motor air intake for use on vacuum motor device with a funnel shaped shroud enclosing a portion of the vacuum motor housing adjacent a fan assembly. Combined with the funnel shaped shroud, a conical air deflection body directs air entering the motor in a laminar flow pattern.

Abstract: Ventilation system for household appliances, in particular for washing machines, comprising a device (1) having at least

Abstract: An electric motor having an armature which includes a coating of thermally conductive plastic applied in a conventional injection molding process. The armature also includes a fan which is integrally formed from the thermally conductive plastic applied to the armature. This completely eliminates the need to apply one or more coatings of a trickle resin to the armature. It also eliminates the need to separately form and secure a fan by a suitable adhesive to the armature, which together significantly simplifies the manufacturing and cost of the armature. The plastic coating also better fills the spaces between the magnet wires, thus promoting even more efficient cooling and better holding of the magnet wires stationary relative to one another. The thermally conductive plastic coating may be mixed with other suitable materials to provide a density approximately equal to the magnet wires. This eliminates the need to balance the armature after the injection molding step.

Abstract: A superconducting machine includes a superconductive device and a vacuum enclosure containing and thermally insulating the superconductive device. A cold-trap is configured to condense gases generated within the vacuum enclosure, and a coolant circulation system is adapted to force flow of a cryogen to and from the superconductive device and the cold-trap. A cryogenic cooling system is configured to cool the cryogen in the coolant circulation system upstream of the superconductive device. A vacuum retention method, for a high-temperature superconductive HTS device, includes applying vacuum to the HTS device to thermally insulate the HTS device, condensing gases generated around the HTS device using a cold-trap, flowing a cryogen to and from the HTS device, and flowing the cryogen to and from the cold-trap.

Abstract: An alternator fan having a generally disc-shaped body with opposed first and second faces. The body includes a plurality of ribs that define raised peaks on the first face and recessed valleys on the second face.

Abstract: A yoke receives an armature and a cooling fan and has air inlet and outlet openings. A water blocking cover substantially covers the inlet and outlet openings of the yoke. The cover includes an intake duct, an exhaust duct and a partitioning member. The air is drawn from outside of the cover into the air inlet openings through the intake duct upon rotation of the fan. The air is discharged from the air outlet openings to the outside of the water blocking cover through the exhaust duct upon the rotation of the fan. The partitioning member is located in a space between the water blocking cover and the yoke and restrains free communication of the air between the intake duct and the exhaust duct through the space between the water blocking cover and the yoke.

Abstract: An air cooler device for an enclosed rotational electrical machine includes an air inlet and an air outlet provided in the casing of the electrical machine, and a fan simultaneously driven by the machine's power output shaft, an independently installed fan device, or both a simultaneously driven and an independently installed fan device. The fan or fans pump air or other selected gases inside the rotational electrical machine to allow a cooling air stream to flow through the outlet to an air cooler for indirect heat dissipation, and then back to the rotational electrical machine through the inlet.

Abstract: A rotating machine has a case with an exterior surface, a pulley end, an opposite end, and an interior working chamber. A rotary shaft is mounted for rotation within the interior working chamber between the pulley end and the opposite end. At least one machine component is supported for rotation on the rotary shaft. At least one air inlet and at least one air outlet are formed through the case. A first fan is supported for rotation on the rotary shaft within the interior of the case and is arranged for pulling air through the air inlet into the interior working chamber of the case and for pushing air out the air outlet from the interior working chamber of the case. A cowl is received over the opposite end of the case. The cowl defines a plenum between an interior surface of the cowl and the case and also defines an annular air opening around a perimeter of the cowl and the case.

Abstract: A fan-flywheel-pulley assembly for use in conjunction with an electric motor. The assembly may include a pulley positioned about a central axis. The assembly may also include a flywheel coupled to the pulley and positioned about the central axis, the flywheel including an outer circumferential flywheel surface partially forming a plurality of circumferentially spaced openings. The flywheel may also include a baffle that extends circumferentially in close proximity to a cylindrical wall unit of the motor from an inner diameter to an outer diameter to limit a gap between the baffle and the cylindrical wall unit. Further, the assembly may also include a radial fan disposed within the flywheel including a plurality of blades extending at least from the flywheel inner diameter to the outer diameter each opening is positioned between each adjacent fan blade. The pulley, the flywheel, and the radial fan may be integrally formed.

Abstract: A pump housing (14, 16) has a fan guard (40) secured to the end of the housing by four crescent-shaped tabs (60) fitting into four crescent-shaped cast-in recesses (66) of the housing (14, 16) and ears (68) of the tabs (60) fitting into cast-in holes (70) in the housing (14, 16). The ears (68) and boles (70) on opposite sides of the housing (14, 16) are aligned along a common axis (80, 82). The ears (68) are tapered at their leading ends (90) and squared off at their trailing ends (92), and the guard (40) has a radial projection (56) that fits into an opening in the housing (14, 16).

Abstract: A monodirectional impeller for centrifugal electric pumps having a permanent-magnet synchronous motor, having vanes which are deformable at least along part of their extension so as to change their curvature, when loaded, in one direction of rotation, so that the power required for rotation in that direction is greater than the maximum power that can be delivered by the motor.

Abstract: It is an object of the present teachings to provide a technique that rationalizes the structure of the brushless motor so as to save space in the power tool. According to the present teachings, a representative brushless motor utilized in a power tool may comprise a stator, a rotor and a cooling fan. The brushless motor is disposed within the power tool. The brushless motor is adapted to supply driving current to the stator to drive a tool bit of the power tool by rotating the rotor. The cooling fan is molded of a magnetic or conductive material so that the cooling fan also serves as a rotating position detector that detects the rotating position of the rotor with respect to the stator. Because the cooling fan may also have a function of rotating position detector of the rotor, the inner space of the power tool can be rationalized.

Abstract: The invention relates to an electric fan, in particular, for motor vehicles, comprising an electric drive motor, a fan wheel coupled with the drive motor, and an electronic control unit for controlling the motor. In order to make the electric fan structurally more simple and more cost-effective to assemble, it is proposed that the drive motor and the control unit be arranged in a common housing, and that the housing have air vents for passage of a flow of cooling air generatable by the fan wheel, and a heat sink of the control unit be arranged at at least one air vent.

Abstract: An alternator includes an inner housing and an outer housing. A pair of o-rings positioned therebetween create a sealed flow chamber having a first flow channel, a second flow channel and an axial passageway. The first flow channel is a disk shaped cavity extending diametrically across the alternator. The second flow channel forms an annular jacket extending entirely around the alternator. The axial passageway directs coolant axially from the first flow channel into the second flow channel. An inlet positioned diametrically across from the axial passageway allows coolant to enter the first flow channel, such that coolant entering the inlet must flow diametrically across the alternator to reach the axial passageway. An outlet positioned diametrically across from the axial passageway allows coolant to exit the flow chamber, such that coolant entering the second flow channel must travel annularly around the alternator to reach the outlet.

Abstract: A muffler is incorporated into an electric motor housing to increase air flow across the motor and to reduce noise escaping from the housing. The muffler includes a cone adapted to be mounted adjacent the exhaust side of the motor fan. The muffler further includes an exhaust passageway comprising at least 270° in turns before final exhaustion.

Abstract: The aim is to improve the cooling of a self-ventilated electric motor (1). To this end, an electromagnetic speed limiting and governing device is provided between the motor shaft (3) and the fan wheel (2), the fan wheel, which is driven via an electromagnetic slip coupling (6, 10) in accordance with the motor speed, being mounted freely rotatably on the motor casing or on the motor bearing plate (5).

Abstract: A turbogenerator cooling system is disclosed that has a cylindrical heat sink with generally axially extending fins on both the outside and inside of a hoop section. The hoop section is solid except for holes adjacent to the rear end thereof. The generator stator is press-fitted into the heat sink in contact with the internal fins. The generator rotor is fitted with a small fan for directing heated air away from the inlet of the engine. Cooling air passes along the external fins to the rear of the generator, flows through the holes in the hoop section passes forward between the inside of the hoop section and the external surface of the stator to cool the stator and along an alternate path to cool the rotor hollow sleeve and permanent magnetic shafts as well as the stator.