Abstract: An apparatus (1) includes a housing (2), an air feed duct (21) a volute (5), an impeller (4), and a motor (3) for driving the rotation of the impeller (4) so as to generate a centrifugal air flow in the volute (5). The housing (2) has a first part (18a) where wall is intended, after assembly, to extend around the motor (3), espousing the shape of this motor (3) in such a way as to lie at a substantially constant distance from this motor (3); and a second part (18b, 19) where wall is intended, after assembly, to extend around the volute (5), espousing the shape of this volute (5) so as to lie at a substantially constant distance from this volute (5). The housing (2) internally forms a salient axial lump (20) which, after assembly, sits close to the hub (10) of the impeller (4).

Abstract: It is an object to provide an inverter-integrated electric compressor capable of enhancing the cooling of high-voltage components, which generate a large amount of heat, among components of an inverter device disposed inside an inverter box integrated with a housing. An inverter-integrated electric compressor (1) for a vehicle air conditioner includes an inverter box (11) that is integrated with the periphery of a housing (2) accommodating an electric motor (9) and a compressing mechanism, an inverter device (20) that converts DC power to three-phase AC power and supplies it to the electric motor (9) being accommodated in the interior thereof, wherein, when the electric compressor is installed in a vehicle (30), among components of the inverter device (20), high-voltage components (21, 22) generate a large amount of heat are disposed inside the inverter box (11) at positions facing forward in a vehicle traveling direction.

Abstract: A thermal conductor for a heat-generating liquid pump system of a pool containing liquid and including a pipe. The conductor is adapted for conducting heat from the pump system to liquid circulated by the pump system. The conductor includes a body in thermal communication with a heat generating portion of the pump system and in thermal communication with only an outside surface of the pipe and not in direct contact with the liquid.

Abstract: In an axial fan including a motor, a substrate that connects the ends of a plurality of coils is disposed at a position axially under the bottom portion of a case with an axial gap therebetween. A spacer is interposed between the substrate and the bottom portion, and the substrate is fixed to the spacer. A plurality of through holes provided in the bottom portion are disposed in axial alignment with a plurality of through holes provided in the spacer. An air flow produced by rotation of an impeller at least partially passes through the interior of the case to be discharged to the outside of the case through the through holes in the bottom portion and in the spacer so that heat generated inside the motor can be efficiently transferred to the outside of the case.

Abstract: A blower providing a blower mode and a vacuum mode. A casing provides a motor housing installing a motor and a fan housing installing a centrifugal fan rotationally driven by the motor. A partition is disposed and having a first surface defining a motor housing and second surface defining a fan housing. The fan includes a generally circular base plate having one surface in direct confrontation with the second surface. A plurality of base plate through-holes arrayed in an imaginary circle whose center is coincident with the rotation axis of the fan are formed in the base plate. The partition is formed with a plurality of partition through-holes arrayed in the imaginary circle and in selective alignment with the base plate through-holes in accordance with the rotation of the centrifugal fan. Each partition through-hole includes a width increasing region where a width of the partition through-hole in the circumferential direction is gradually increased toward the second surface.

Abstract: An electrical motor for an electrical submersible pump wherein the electrical motor has increased heat transfer capabilities. The electrical motor includes a housing and a plurality of stator laminations within the housing. Each stator lamination defines a central orifice and a plurality of lamination slots. A plurality of magnet wires pass through each of the plurality of lamination slots formed by the stacked plurality of stator laminations. Shrink wrap surrounds each of the plurality of magnet wires to secure the magnet wires in bundles. The result is that the wires are effectively bound together in a manner that allows oil to move freely inside the lamination slots surrounding the wire bundles. Since fluid can pass between and around the windings, the overall winding temperature will be normalized, essentially reducing hot spots that occur in prior art designs.

Abstract: A small size gear pump having a disc-shaped case, inside which a flat cylindrical motor rotor chamber, a bearing chamber and a flat cylindrical gear chamber are arranged eccentrically from the bearing chamber and the rotor chamber, which are piled sequentially along an axial direction and are communicating to each other.

Abstract: The invention relates to a device to compress combustion air, in particular a device to compress combustion air for a combustion engine of a motor vehicle, with a housing (12), with at least one compressor impeller (30) arranged in a compression area (28) of a first housing part (14), which is arranged in the flow direction between an air inlet (24) and an air outlet (43) of the housing (12), as well as with an electric motor (18) arranged in a second housing part (16) of the housing (12) to operate the compressor impeller (30). It is proposed in accordance with the invention that a flow channel (42) running in the circumferential direction of the first housing part (12) and connecting the compression space (28) with the air outlet (43) surrounds the electric motor (18) at least partially.

Abstract: A gas compression system that includes an electric motor that drives a compressor, a gas treatment device, and a gas cooling device. The electric motor may be cooled by a circulating flow of gas that is cooled by the gas cooling device and had been treated by the gas treatment device. The gas compression system may further include a gas feed that provides a supply of raw gas and a valve connected to the gas feed that controls a flow of raw gas from the gas feed to the gas treatment device. The valve may control the flow of raw gas from the gas feed to the gas treatment device such that any of the circulating flow of gas that is lost due to leakage is replaced. The gas treatment device may remove corrosive or abrasive impurities from the supply of raw gas.

Abstract: A scroll compressor includes various features that promote a bifurcated flow pattern of gas through a compressor shell to reduce oil entrainment. After entering the shell, some gas travels upward, which reduces the volume of gas traveling downward toward an oil sump. To accomplish this, the compressor's motor can be surrounded by a sleeve having upper and lower apertures for directing the flow to the motor's upper and lower stator end turns. In some embodiments, a suction inlet is strategically positioned relative to two gas passageways that are between the stator and the compressor shell. The inlet's position is such that one passageway receives incoming gas and divides the flow in opposite directions: upward and downward. The other passageway only conveys the gas upward. In addition, a suction baffle, a diffuser, a streamlined counterweight and/or a suction line oil trap can also help promote gas/oil separation or minimize oil entrainment.

Abstract: The production rate, useful life and operating efficiency of electric submergible pumping systems (ESP) is improved by operating the system so that the motor (220, 320) is cooled by two passes of production. Production fluids remove waste heat from the motor (220, 320) by passing the fluid in contact with the exterior of the motor (220, 320). The improved cooling permits the motor to be operated at a lower temperature improving life and efficiency, and/or to be operated at higher power at a similar temperature. Additionally, oversized and excess equipment is not required, further improving performance and economics for the user. In another aspect, the invention is a method of pumping fluids using a motor having vortex generators (366) on its exterior surfaces or on the interior surfaces of a surrounding shroud.

Abstract: A compressor includes a motor having a rotor for driving a shaft, to drive compressor pistons. A lubricant supply system supplies lubrication to the moving elements within the compressor and motor. A suction fluid to be compressed passes over the motor on its way to the compression chambers. The oil is returned from a bearing mounting an end of the shaft intermediate the motor rotor and the compressor pistons. The bearing mount ensures that the lubricant is returned away from the motor rotor, to reduce the amount of oil that is entrained in the fluid to be compressed.

Abstract: An electro-hydraulic power unit is disclosed that includes a housing filled with hydraulic fluid. A hydraulic power unit is disposed within the housing, the power unit having a mechanical power shaft. Additionally, an electric machine is disposed within the housing adjacent to the hydraulic power unit, the electric machine having a rotor secured to the mechanical power shaft of the hydraulic power unit. Hydraulic fluid within the housing passes over the electric machine, thus cooling the electric machine and providing for improved efficiency and performance.

Abstract: An electric compressor has a compressor housing, a compression mechanism, an electric motor, an accommodating portion and a motor drive circuit. The compressor housing has a circumferential wall and a central axis. The compression mechanism is arranged in the compressor housing for compressing fluid. The electric motor is operatively connected to the compression mechanism for driving the compression mechanism. The accommodating portion is provided on an outer surface of the compressor housing and defines an accommodating space. The inner surface of the accommodating space includes a bottom surface and a side surface. The bottom surface is defined as a radially inward surface of the inner surface relative to the central axis. The side surface surrounds a periphery of the bottom surface. The bottom and side surfaces are defined by the compressor housing. The motor drive circuit is arranged in the accommodating space for driving the electric motor.

Abstract: The fuel transfer pump is a combination suction and pressure pump in a manifold above the fuel storage tank. The fuel transfer pump is contained within a manifold. The pump is liquid cooled (more specifically, fuel cooled) and is located in a manifold above the fuel storage tank and not submerged inside the tank. The fuel transfer pump draws (using suction) the fuel up from the bottom of the tank though the pipe column into the manifold and then under pressure pumps it to one or more fueling dispensers.

Abstract: A transcritical vapor compression system includes a compressor assembly that includes an oil separator for separating oil from refrigerant. The oil separator is disposed between a motor and a compression chamber in a sub-critical portion of the vapor compression system. Oil emitted from the drive assembly attached to the motor is substantially removed from the refrigerant before entering the compression chamber of the compressor.

Abstract: A horizontal-type electric motor driven compressor comprises a casing, a suction chamber formed in the casing, an electric motor arranged on a suction chamber side in the casing, a compressor section driven by the motor in the casing about a horizontal axis of rotation extending in a longitudinal direction of the casing, a suction opening provided in the compressor section, and a refrigerant passage having an inlet communicating with the suction opening and communicating the suction chamber to the suction opening. The refrigerant passage is the sole refrigerant passage between the suction chamber and the suction opening. The inlet of the refrigerant passage is provided in a lowermost portion at a bottom of the casing.

Abstract: Suction gas feed assemblies to provide gas to a hermetic compressor are provided. The feed assemblies have capacity for reducing suction noise resulting from suction conduit vibration, valving operation, suction gas pulsing, or the like. The suction gas feed assemblies include a suction plenum in the form of a substantially cylindrical end cap or motor cap having substantially straight side wall, a contoured top wall, and a gas inlet aperture and suction conduit aperture which are configured to provide strong suction and motor cooling, with reduced superheat, suction pulsation, and noise attenuation. The motor cap has excellent structural stiffness and low sound radiation.

Abstract: A hermetic compressor which uses carbon dioxide as the working fluid. The compressor includes a motor and a compression mechanism operatively coupled by a drive shaft supported by a bearing. The drive shaft includes a radially extending bore in fluid communication with an oil supply passageway in the drive shaft and the outer periphery of the drive shaft. An oil accumulating cavity is located beneath the radially extending bore in which oil is stored during compressor shutdown to provide oil to bearing surfaces upon compressor startup. An oil return system includes a chamber located at one end of the drive shaft and an oil return passageway extending from the chamber to an annulus formed between the bearing and the drive shaft. The oil in the annulus lubricates the bearing and drive shaft interface. A discharge tube is provided having means for aspirating oil from an oil containing sump when the oil in the oil sump reaches a particular level.

Abstract: An enclosed-configuration electrically powered compressor has an electric motor with a segment-type stator coil that is directly cooled by a flow of refrigerant from an intake aperture in the casing, directed onto one or both of the coil end portions of the stator coil. Each coil segment is formed of a U-shaped conductor having rectangular cross-section, with each coil end portion having regular spaces formed between the conductors such as to present low resistance to the flow of refrigerant, with the refrigerant also flowing through the rotor/stator air gap of the motor.

Abstract: Lubricating liquid fed from a reservoir to a compression mechanism is collected by a circumferential wall that surrounds the drive shaft of the compression mechanism and rotates synchronously with it immediately after liquid is discharged into the space inside the housing with or without compressed fluid. Liquid is then urged outward under centrifugal force from an outlet formed at a preset axial location of the circumferential wall. Exiting liquid is received by a fixed liquid return cover that surrounds the circumferential wall near its outlet and led back to the reservoir.

Abstract: An improved structure of an air inflation device is disclosed. External air is drawn to the motor and cylinder to provide rapid cooling so that the efficiency of the motor is maintained. In the present invention, a plurality of air filters is used to filter air. Thereby the air inflation device is useful and practical.

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: An electro-hydrostatic actuator having a sealed housing filled with a dielectric fluid. A motor driven pump and electronics for controlling the pump are all immersed in the fluid. The pump is arranged to deliver fluid from the housing to a hydraulic cylinder to control the positioning of the piston rod. A solenoid operated valve is integrated as a bypass or tip valve for quick fail safe position. The actuator is ideally suited to control various types of plunger valves. In one embodiment of the invention, the hydraulic cylinder is located outside of the housing and in another embodiment the cylinder is located inside of the housing.

Abstract: A blower includes a base having a transverse passage for receiving a motor therein and a fan device driven by the motor extends from a hole in an end of the base. A casing including an outlet is connected to the base and mounted to the fan device. An anti-back device is engaged in the outlet and includes a frame to which a plate is pivotably connected. The plate is opened by the air sent via the fan device in one direction and seals the outlet when air goes in opposite direction.

Abstract: A motor-driven compressor for compressing a refrigerant in an air conditioning system includes an electric motor, a swash plate-type compression unit driven by the electric motor, and a cooling channel for returning the refrigerant used by the air conditioning system to a suction chamber of the compression unit. The cooling channel has an upstream section including an armature chamber of the electric motor, and a downstream section extending from the armature chamber to the suction chamber in such a manner that the downstream section is separated from a crank chamber of the compression unit.

Abstract: A scroll compressor includes various features that promote a bifurcated flow pattern of gas through a compressor shell to reduce oil entrainment. After entering the shell, some gas travels upward, which reduces the volume of gas traveling downward toward an oil sump. To accomplish this, the compressor's motor can be surrounded by a sleeve having upper and lower apertures for directing the flow to the motor's upper and lower stator end turns. In some embodiments, a suction inlet is strategically positioned relative to two gas passageways that are between the stator and the compressor shell. The inlet's position is such that one passageway receives incoming gas and divides the flow in opposite directions: upward and downward. The other passageway only conveys the gas upward. In addition, a suction baffle, a diffuser, a streamlined counterweight and/or a suction line oil trap can also help promote gas/oil separation or minimize oil entrainment.

Abstract: Compressor, comprising a sealed outer casing, inside which is arranged a gas compression stage driven by a motor arranged inside the outer casing. The lower part of the inner casing containing the motor is sealingly closed by a bottom, and at least one vertical chimney is arranged in the annular space formed between the outer casing and the lower casing, the chimney being arranged substantially vertically along the motor and the lower casing, and communicating in its upper part with the low-pressure zone of the compressor and, in its lower part, with the inside of the lower casing, one or more openings being made between the chimney and the bottom of the motor.

Abstract: A system for cooling a turbo compressor includes two compressing parts on opposite ends of a rotational shaft driven by a motor. Fluid from a fluid chamber within the casing of the device is supplied to a bearing chamber when the temperature of the bearing chamber increases. A supply passage is formed in a first support where the radial bearing for supporting a load in the axial direction is formed. The open-and-shut valve supplies fluid when the temperature of the bearing chamber increases.

Abstract: An air pump is provided with a motor body having an air slot to allow air to flow from the air slot to air inlets positioned in a front sealing cap of the motor body. The air inlets are aligned with air holes in a closed housing. A shaft of the motor body extends into the closed housing which houses a piston. The shaft of the motor body is connected to gearing mechanisms in the closed housing to provide reciprocating motion of the piston. The piston includes an air inlet and a valve. The reciprocating movement of the piston causes air to travel through the piston into a cylinder above the piston. The design of the pump affords a cooling function to both the motor body and cylinder while reducing the noise of the pump.

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 compressor and an electric motor in which their weights are successfully reduced by employing a light-metal conductor wire for a winding, by reducing constituent components of a stator and a rotor of the electric motor, by providing a notch or a hole, and by eliminating the need for components necessary to mount the stator in a housing or a casing.

Abstract: A turbo compressor includes: a casing having a fluid chamber for receiving a fluid from an external source; a driving unit disposed in the casing and generating a rotational force; a first compressing part installed at one side of a rotational shaft rotated according to the driving of the driving unit and first compressing the fluid; a second compressing part installed at the other side of the rotational shaft and secondly compressing the fluid compressed in the first compressing part; and a bearing cooling unit for supplying a fluid of the fluid chamber to a bearing chamber to perform a cooling operation when a temperature of the bearing chamber where the thrust bearing for supporting a load working in an axial direction of the rotational shaft is mounted is increased, and cutting off the fluid from being introduced into the bearing chamber when the temperature of the bearing chamber is maintained at a proper level.

Abstract: An electric compressor includes a compression mechanism, an electric motor and a housing. The compression mechanism draws, compresses and discharges refrigerant gas. The electric motor drives the compression mechanism. The housing accommodates the compression mechanism and the electric motor. A heat sink extends from the housing. An inverter is located in the housing. The inverter powers the electric motor. A heat sink cools the inverter. The heat sink is cooled by refrigerant gas. The heat generated by the inverter is therefore effectively reduced.

Abstract: In order for a compressor for refrigerant, comprising

Abstract: A motor-driven pump with a plurality of impellers, includes a pump housing provided on an electric motor, and an impeller unit provided in an inner space of the housing, the housing having two fluid inlet port regions on two sides near and away from the motor in a longitudinal direction of an output shaft of the motor, and having one fluid discharge port region between the inlet port regions, and the unit including a pair of impellers having a partition wall fixed to the output shaft, directing to the discharge port region, and partitioning the inner space into two portions near and away from the motor, and a pair of blade groups provided on both sides of the partition wall.

Abstract: A housing for a screw compressor, includes a single-piece casting defining a motor housing section and a rotor housing section and has an inlet for compressor medium, an outlet end and a bridge member disposed between the motor housing section and the rotor housing section and defining an inlet side bearing housing; a discharge housing mounted to the outlet end and defining an outlet and a discharge side bearing housing; and at least one rotor disposed in the rotor housing section and rotatably mounted between the inlet side bearing housing and the discharge side bearing housing.

Abstract: A furnace blower has an inexpensive and compact coaxially arranged simplified construction that includes an electric motor having a shell with radially projecting fins that is press-fit into a cylindrical blower housing and a combustion tube that is also press-fit into the blower housing where the interior of a combustion tube is positioned in close proximity to a fan on the motor shaft. The press-fit assembly of the motor into the blower housing as well as the combustion tube into the blower housing simplifies the construction of the furnace blower and reduces its manufacturing costs. The furnace blower is also smaller than prior art furnace blowers which enables it to be readily retrofit into conventional furnaces in place of prior art furnace blowers.

Abstract: A refrigerant passage within a main shaft includes an axial refrigerant passage extending in parallel with the main shaft from the end surface thereof, and a radial refrigerant passage communicating with the axial refrigerant passage and extending radially outwardly. The radial refrigerant passage is located between the end surface of the main shaft and a motor rotor. Thus, when the main shaft rotates, suctioned refrigerant is uniformly sprayed toward an entire coil. Further, the refrigerant flows toward a compression mechanism through the electric motor, thereby cooling the electric motor effectively.

Abstract: A blower machine having a motor on the internal section of a motor mount that drives rotation blades into rotary motion. There is a turning wheel consisting of two conjoined discs, with the rotation blades centrally anchored between the discs and an air output opening situated in the rotational direction of the rotation blades to provide for gaseous discharge. An air intake opening of the lower blower machine is located at the bottom end of the motor mount. When the rotation blades revolve, an air flow is induced from the exterior through the air intake opening and forms a flow channel of cold air that continuously cools the motor.

Abstract: A pump end cap preferably includes a plastic molding that is shaped to include an external electrical socket and is internally shaped to include electric motor brush placement holders. Electric motor brushes are mounted on the holders. The electric motor portion of the electronic pump assembly is completed when the end cap is mated to an appropriate housing. By integrating a portion of the electric motor into the pump end cap, the need for wires extending from an electric motor terminal to the outside of the pump housing is eliminated. The present invention preferably finds application in fuel pump and filter assemblies used in conjunction with diesel type internal combustion engines.

Abstract: The present invention relates to a drive mechanism for a pump (10) implemented by means of a drive motor (20), the rotational speed and torque of which are influenced by a frequency converter (30). The frequency converter (30) is arranged on a heat dissipator (40) confining a flow of the pressure liquid guided to the pump (10). It is advantageous to also arrange the drive motor (20) inside the said heat dissipator (40), for this makes it possible to perform intense forced air cooling of a pump-drive motor system without the necessity of an additional cooling liquid. The drive motor (20) preferably has a central arrangement inside a tubular heat dissipator and is exposed to the pressure liquid over its entire circumference. Baffles or offset connecting sleeves allow for uniform flow through the entire heat dissipator (40).

Abstract: An air compressor includes a housing having a port formed in a motor casing and another port formed in a fan casing. The fan casing has a mouth for air to flow into the housing. The mouth may be selectively blocked for facilitating the drawing of the air into the housing via the ports. The fan device includes a plate having two sides and having one or more blades extended from each of the sides of the plate for facilitating the air circulating or paddling or drawing effect of the air compressor. The blade is preferably extended radially and laterally relative to the plate.

Abstract: A compressor system includes a housing with a low pressure first chamber and a high pressure second chamber. A motor in the first chamber has a shaft that passes into the second chamber. A compressor in the housing is operably connected to the motor by the shaft. The second chamber contains an oil sump storing lubricating oil for the compressor. A fluid path through the compressor system includes a first orifice in the housing communicating a suction tube with the first chamber, a first fluid passage communicating the first chamber with the compressor suction port, a second fluid passage communicating the compressor discharge port with the second chamber, and a second orifice in the housing communicating the second chamber with a discharge tube. By the action of the compressor, the fluid in the first chamber is maintained at compressor suction pressure and the fluid in the second chamber is maintained at compressor discharge pressure.

Abstract: A scroll compressor has a reduced height by having its suction tube aligned with its motor stator windings. The oil is returned from the scroll compressor to a compressor sump by confining the oil to flow through any of several structures such that it is isolated from refrigerant passing into a suction chamber through the suction tube. In this way, the oil which has been typically returned between the stator and the inner wall of the housing does not communicate with the refrigerant which is entering the housing. While the invention is shown in scroll compressor, it has benefits in other type compressors.

Abstract: A compressor and an electric motor in which their weights are successfully reduced by employing a light-metal conductor wire for a winding, by reducing constituent components of a stator and a rotor of the electric motor, by providing a notch or a hole, and by eliminating the need for components necessary to mount the stator in a housing or a casing.

Abstract: An electric pump for a liquid has a rotor surrounded by a stator which is disposed in the flow path of the liquid, the rotor being disposed in a rotor compartment, which is sealed from the flow path of the liquid and is predominantly filled with a mixture of air and vaporized liquid. The rotor compartment is in communication with the ambient atmosphere through a vent orifice. A vent system in the form of a labyrinth seal and a liquid-tight, gas-permeable membrane is interposed between the vent orifice and the ambient atmosphere. The rotor bearings are lubricated in one embodiment by leakage liquid and its vaporized product within the rotor compartment. In another embodiment the rotor bearings are disposed in the liquid flow path outside seals between the rotor and the rotor compartment.

Abstract: A hermetic rotary compressor comprising a housing, a cylinder block and a bearing assembly in the housing and defining a cylindrical cavity therein. A roller piston, drivingly coupled to a motor, is disposed in the cylindrical cavity. The cylinder block includes a reciprocating vane within a vane slot defined therein. The vane slot extends axially through said cylinder block, radially from an outside perimeter surface of the cylinder block to the cylindrical cavity. At least a portion of the vane slot is defined by a pair of substantially parallel sidewalls with the vane disposed in the vane slot and urged against the roller piston. The vane is guided by the substantially parallel sidewalls and a clearance exists between the vane and the substantially parallel sidewalls.

Abstract: A motor-driven pump with a plurality of impellers, includes a pump housing provided on an electric motor, and an impeller unit provided in an inner space of the housing, the housing having two fluid inlet port regions on two sides near and away from the motor in a longitudinal direction of an output shaft of the motor, and having one fluid discharge port region between the inlet port regions, and the unit including a pair of impellers having a partition wall fixed to the output shaft, directing to the discharge port region, and partitioning the inner space into two portions near and away from the motor, and a pair of blade groups provided on both sides of the partition wall.

Abstract: A refrigerant passage within a main shaft includes an axial refrigerant passage extending in parallel with the main shaft from the end surface thereof, and a radial refrigerant passage communicating with the axial refrigerant passage and extending radially outwardly. The radial refrigerant passage is located between the end surface of the main shaft and a motor rotor. Thus, when the main shaft rotates, suctioned refrigerant is uniformly sprayed toward an entire coil. Further, the refrigerant flows toward a compression mechanism through the electric motor, thereby cooling the electric motor effectively.