Abstract: A method and a controller for controlling a magnetic bearing device, in which a rotor is suspended for rotation around a shaft, are disclosed. Sensor signals are transformed to yield tilt displacement signals (S?x, S?y) which correspond to tilting displacements of the shaft in predetermined directions (x, y). From the tilt displacement signals (S?x, S?y), tilt control signals A?x, A?y) are derived; these are transformed to yield actuator control signals for driving electromagnetic actuators in the magnetic bearing device. According to the invention, tilting displacements for which the tilt vector rotates about the device axis (z) with a first predetermined sense of rotation are controlled separately from tilting displacements for which the tilt direction vector rotates about the device axis (z) with a second sense of rotation opposite to the first predetermined sense of rotation. In this way, control of nutation and precession can be achieved without influence from blade vibrations or shaft bending modes.

Abstract: A two-stage vapor cycle compressor includes a first stage impeller, a second stage impeller situated adjacent to the first stage impeller, an electric motor running on a pair of foil bearings, a thrust disk including two foil bearings and being positioned between the second stage impeller and the electric motor, and a compressor housing enclosing the first and second stage impeller and the electric motor. A refrigerant vapor compressed by the first stage and second stage impeller flows through an internal passageway formed by the compressor housing and cools the foil bearings and the electric motor. The compressor may be a gravity insensitive, small, and lightweight machine that may be easily assembled at low manufacturing costs. The two-stage vapor cycle compressor may be suitable for, but not limited to, applications in vapor compression refrigeration systems, such as air-conditioning systems, for example, in the aircraft and aerospace industries.

Abstract: A cooling fan includes a fan housing (10) having a central tube (11) extending upwardly therefrom, a bearing (20) received in the central tube, a stator (40) mounted around the central tube, a rotor (30) having a shaft (37) extending into the bearing, and a magnetic ring (38) being fixedly mounted to the rotor to rotate with the rotor during operation of the cooling fan. The bearing is made of iron-copper alloy. The magnetic ring is made of hard magnetic material and exerts a magnetic attraction on the bearing, whereby the rotor is pulled downwardly by a magnetic attraction of the bearing on the magnetic ring to lessen the floating problem of the rotor during operation of the cooling fan.

Abstract: A ball bearing (1) has an inner race (2) and an outer race (3). In order to prevent the rotating parts from being damaged when the bearing assembly fails, the bearing has emergency bearing surfaces (14, 15) which are concentric to the rotational axis (6) and of which one is a part of the rotating bearing race and the other is a part of the fixed bearing race. During normal operation, the emergency bearing surfaces (14, 15) are situated opposite one another with a relatively narrow gap (24) therebetween. But, in the event of failure, the surfaces (14, 15) engage and function as emergency bearing surfaces.

Abstract: A cooling fan includes a fan housing (30) having a central tube (34) extending upwardly therefrom; the central tube has a bottom, annular protrusion (31). A bearing (61) is received in the central tube and mounted on the protrusion. A stator (20) is mounted around the central tube. A rotor (10) includes a shaft (18) having a free end (186) extending through the bearing and defining a notch (184) therein. A locking washer (63) engages into the notch of the shaft to limit movement of the shaft along an axial direction thereof. A balance structure (62) is arranged between the locking washer and the bearing. The balance structure is made of magnet and exerts a downwardly pulling force on the shaft to prevent the rotor from moving upwardly when the rotor is rotated.

Abstract: The invention concerns a method for mounting a drive shaft (19) of a compressor, particularly a hermetical refrigerant compressor, which has a motor with a stator (1) and a rotor (23), connected with the drive shaft (19) and located in a rotor opening (4) of the stator (1), a first bearing support (8) and a second bearing support (29) being connected with the stator (1), a first bearing (15) for the drive shaft (19) being mounted in the first bearing support (8) and a second bearing (28) for the drive shaft (19) being mounted in the second bearing support (29). It is endeavoured to provide a method for mounting a drive shaft, in which the use of components with relatively large manufacturing tolerances will still result in a good alignment of the drive shaft in relation to the stator. For this purpose, at least the first bearing support (8) is provided with a positioning stop for the first bearing (15) after mounting the first bearing support (8) on the stator (1).

Abstract: A submersible pump unit having a wet-running electric motor and only a single impeller can be driven by the electric motor with a rotation speed greater than 20,000 rpm. The rotor of the electric motor has a diameter of less than 25 mm.

Abstract: In a magnetically levitated pump, an impeller-side ferromagnetic body (second ferromagnetic body) provided on a circumferential surface of an impeller facing a casing unit on the side of a position sensor and a casing-side ferromagnetic body (third ferromagnetic body) opposite to the impeller-side ferromagnetic body (second ferromagnetic body) to attract the impeller toward the casing unit on the side of the position sensor are adapted to have opposite portions of mutually different shapes, so that the maximum required attractive force of an electro-magnet for magnetic bearing is suppressed and length of the electro-magnet for magnetic bearing is made shorter.

Abstract: A device for axially conveying fluids, wherein the conveyor part thereof is entirely magnetically borne and the radial bearing thereof is provided with sufficient rigidity and efficiently dampened, whereby problems encountered when passing through critical speeds and the disadvantageous effects of hydrodynamic and mechanical imbalance of the rotor are avoided. The magnetic bearing is combined with a hydrodynamic bearing.

Abstract: A blower includes a stationary portion including an inlet and an outlet, a rotating portion provided to the stationary portion, and a motor adapted to drive the rotating portion. The inlet and outlet are co-axially aligned. The stationary portion includes a housing, a stator component provided to the housing, and a tube providing an interior surface. The rotating portion includes one or more bearings that are provided along the interior surface of the tube to support a rotor within the tube. In an embodiment, the blower is structured to supply air at positive pressure.

Abstract: A pump for pumping sensitive fluids, such as blood, having no mechanical contact between the impeller and any other structure. The pump comprises a pump housing, an impeller disposed within the pump housing, a magnetic bearing system for supporting and stabilizing the impeller in five degrees of freedom, and a conformally shaped magnetically linked motor for rotating the impeller. The magnetic bearing system and motor advantageously comprise electromagnets and permanent magnets for stability and control of the impeller, and to reduce size, weight, and pump power consumption. Permanent and electromagnets are disposed on the pump housing and permanent magnets are disposed on the impeller such that by controlling electric current through the electromagnets on the housing, the magnetically suspended impeller functions as the rotor, and the housing as the stator of a D.C. motor.

Abstract: An axial flow pump (10) is presented which includes a housing (1) with an inlet (2) and outlet (3) and a magnetically active rotor (5) in the housing which is provided with a passage (6) in the interior and with at least one spiral-shaped vane (7) in the passage, wherein the pitch of the vane (7) varies in the axial direction. The axial flow pump (10) furthermore includes an electromagnetic drive (4, 8) with a stator (8) which is arranged at the housing and cooperates with a magnetically active rotor.

Abstract: If the ambient temperature of a pressure volute measured by a temperature sensor exceeds 0° C., a compressor is instantly started at normal operation. If the temperature of the pressure volute measured by the temperature sensor is 0° C. or lower, there is a possibility that a rotary vane may be adhered to the pressure volute due to a congelation. Therefore, vibration along the axial direction is given to the rotary shaft by way of an axial magnetic bearing. If the vibration amplitude of the thus given vibration exceeds a predetermined value, the compressor is started at normal operation after idle operation. On the other hand, if the vibration amplitude is lower than a predetermined value, it is determined that the thus given vibration is unable to eliminate the adhesion of the rotary vane due to the congelation, and the heater is actuated to heat the pressure volute only for a predetermined time. Thereafter, the ambient temperature is detected again, and if the ambient temperature exceeds 0° C.

Abstract: A miniature blower fan includes an axial seat and a shaft extending from a central portion of the axial seat. A plurality of vanes and a magnet are mounted to an outer circumferential wall of the axial seat. The vanes extend radially outward from the outer circumferential wall of the axial seat and are spaced at regular intervals. The miniature blower fan further includes a casing having an air inlet. The vanes have a thickness larger than 30% of an overall height of the vanes and the magnet. In another embodiment, a web extends radially outward from the outer circumferential wall of the axial seat, the vanes are mounted to a side of the web, and the magnet is mounted to the other side of the web. The vanes have a thickness larger than 30% of an overall height of the web, the vanes, and the magnet.

Abstract: Rotary hydrodynamic blood pumps have been used to treat over a thousand patients. The Jarvik 2000 has supported a patient for seven years and uses blood immersed bearings washed by high flow to avoid excessive thrombus formation. This permits the pump to be very simple and small. Nonetheless, the present Jarvik 2000 bearings and all other mechanical blood immersed bearings of the prior art have a supporting structure that predisposes to thrombus adjacent to the bearings. The present invention provides a bearing structure that eliminates this predilection site for thrombus formation, and may provide indefinite thrombus free operation. The rotor of the preferred embodiment includes a tapered hub fabricated of wear resistant material supported by three posts at each end of the rotor, upon which the rotor rotates. Blood washes the unobstructed spaces between the posts to prevent the accumulation of a torus of thrombus that could enlarge excessively.

Abstract: A heat dissipation fan includes a fan frame, a stator mounted to the frame, and a rotor rotatably disposed around the stator. The fan frame includes a bracket, a central tube for positioning the stator, and a supporting member. The supporting member is made of a material having a higher bending strength than a plastic material used to form the bracket and the central tube. The supporting member includes a main body connected to the central tube, a plurality of ribs extending radially outwardly from the main body, and a plurality of engaging units formed at free ends of the ribs, respectively. The engaging units are embedded in the bracket for integrally connecting the central tube to the bracket.

Abstract: The present invention provides an improved structure of the magnetic shaft of a cooling fan. A magnetic attraction component is comprised of a magnetic ring, a magnetic inductive bottom board, and a magnetic inductive ring. The magnetic field generated by the magnetic ring is guided from the upper and lower side by the magnetic inductive ring and the magnetic inductive bottom board respectively, so that the range of magnetic field scattered by the magnetic ring is effectively and reliably guided and suppressed. The range of the magnetic field is reduced to the smallest possible, and interference with other components is minimized within the cooling fan, working stability and quality of the cooling fan being enhanced.

Abstract: The flattened brushless motor pump sucks liquid from suction port and discharges liquid from discharge port by rotating rotary shaft of flattened brushless motor flattened brushless motor has a stator unit having cores around which a plurality of armature coils are wound and terminals electrically connected to the armature coils, and being formed by molding the cores and the terminals with resin in a watertight manner a rotor unit having magnets disposed facing the cores via a gap, rotary shaft and a yoke fixed to the rotary shaft and holding the magnets, wherein an in-water bearing for sliding the rotary shaft by a water film.

Abstract: A cooling fan includes a fan housing (10) having a central tube (15) extending upwardly therefrom, a bearing (20) defining a bearing hole (22) therein, a stator (30) mounted on the central tube, and a rotor (40) including a hub (12) having a shaft (18) extending from the hub into the bearing hole of the bearing. The bearing is received and fixedly connected to the central tube during the plastic injection molding of the fan housing; thus the bearing and the central tube are integrally connected together. The bearing can be precisely and firmly secured to the central tube of the fan housing.

Abstract: This invention discloses an enhanced thermal deformation resisting bearing of an electric motor. The bearing includes a frame for containing a stator and a rotor. The stator has an axle sleeve sheathed with a bearing. The bearing has a hole groove for dividing the bearing into inner and outer layers. A connecting portion maintains an appropriate interval between the inner and outer layers. An embedded groove is extended inward and disposed at a free end of the axle sleeve. The rotor has an axle, and the periphery of the axle has a groove. The groove corresponds with the connecting portion of the bearing. The rotor has a protruding latch disposed proximate to the axle and embedded into the embedded groove. If the axle rotates in the bearing, the thinner inner layer will be expanded by high temperature, but the thicker connecting portion still maintains the bearing in its position.

Abstract: The invention relates to a centrifugal pump (10) for liquids, comprising a pump spiral housing (12) and a pump wheel (28), which is driven by an integrated electromotor (14, 20, 34, 36), whereby the rotational axis thereof (29) is arranged in a coaxial in relation to the rotational axis (37) of the pump wheel (28). The pump spiral housing (12) is sealed by a sealing ring (72) and is connected to the motor housing by means of a bayonet catch (74, 78) and covers the front side thereof. According to the invention, the motor housing (14) is pot-shaped and is made of plastic and the base thereof (13) which is oriented towards the pump spiral housing (12) forms a common housing wall in relation to the pump spiral housing (12).

Abstract: This invention discloses an electric motor apparatus including a frame, a stator and a rotor in the frame, an axle sleeve at the center of the stator and having an embedded groove extended inwardly and at a free end apart from the connecting position of the frame, a bearing sheathed into the axle sleeve, an axle at the center of the rotor and sheathed into the bearing, a latch at an internal side of the rotor and protruded outward for securing the stator and the rotor, and a ball embedded in the bearing and apart from the free end. By the embedded groove and latch, the stator and rotor are combined, and the axle is pressed against the ball. When the axle is rotated, the ball is driven to roll to reduce the friction, noises and wearing as well as enhancing the life expectancy and efficiency of the electric motor.

Abstract: A pump for carrying supercritical CO2 fluid or liquid CO2 capable of securing reliability by optimizing a bearing part. An angular ball bearing (8) comprises an inner ring (8a), an outer ring (8b), balls (8c) held therebetween, and a cage (8d) holding the balls (8c). Both the balls and the inner and outer rings are formed of a ceramic to form a totally ceramic bearing. Also, the cage (8d) is guided by the outer ring or the inner ring. Specifically, for example, when the cage is guided by the inner ring, the inner peripheral surface (8db) of the cage (8d) opposed to the outermost peripheral surface (8ab) of the inner ring (8a) is guided by the outermost peripheral surface (8ab) of the inner ring (8a).

Abstract: A motor. The motor includes a stator, a rotor, a top magnetic structure, and a bottom magnetic structure. The stator is disposed in a frame. The rotor is also disposed in the frame, corresponding to the stator. The rotor comprises a shaft, extended axially from the rotor. The shaft does not contact the stator or the frame. The bottom magnetic structure is at the bottom of the frame. The top magnetic structure is on the top of the frame. The top and bottom magnetic structures are opposite to each other in an axial direction. Magnetic attraction generated between the first magnetic structure and the second magnetic structure attracts and positions the shaft therebetween such that the first magnetic structure, the second magnetic structure, and the shaft are coaxially aligned.

Abstract: A pump assembly with an electric drive motor is provided in which the rotor (10) is designed as a permanent magnet rotor. The rotor (10), at least in a part region of its axial extension (X), is formed as shaftless and made completely of a magnetizable material, and the magnet poles of the rotor (10) are formed by magnetization of the magnetizable material.

Abstract: A motor is provided including a housing having single and integral motor and bearing cooling inlets. The motor is arranged within the housing and includes a stator and a rotor assembly supported on air bearings. The cooling inlet is in fluid communication with the motor stator and with the air bearings. The motor cooling inlet provides and the bearing cooling inlet provides a uniform pressure on the rotor assembly. The uniform pressures exerted on the rotor assembly produce bearing loads that generally cancel one another. The source of the cooling flow is uncompressed air at low pressure. This may be achieved by providing a vent in the housing that is common to both the motor cooling inlet and the bearing cooling inlet. As a result, journal bearings and seals of substantially the same size may be used.

Abstract: A rotary structure for radiation fans mainly includes a seat for housing a radiation fan and two brackets coupling with the seat to hold two sleeves. The two sleeves are coupled with two rotary ends of a spindle of the radiation fan to confine the spindle to rotate about a single axis. Thereby the spindle can rotate without skewing while the radiation fan is operating, and impact and noise generation can be prevented.

Abstract: A hydrodynamic pressure bearing type pump includes a main body having a fluid flow inlet formed at one end portion thereof and a fluid flow outlet formed at the other end portion thereof and a rotating portion disposed within a fluid flow passage of the fluid within the main body to generate hydrodynamic pressure to let the fluid flow into the fluid flow inlet and to let the fluid flow from the fluid flow outlet to the outside. The rotating portion includes a shaft, a hydrodynamic pressure bearing for generating hydrodynamic pressure to let the fluid flow into the fluid flow inlet and to let the fluid flow from the fluid flow outlet to the outside when the shaft is rotated and a rotation force generating portion disposed within the main body to generate rotation force for rotating the shaft when it is energized.

Abstract: Small, high-performance centrifugal fan for cooling portable electronic devices. The centrifugal fan motor employs a cantilever-type impeller constituted by an impeller blade unit that includes a lower endwall portion at axial one end, having a wall surface for breaking the flow of air along the rotational axis, and an opening at the other axial end. The impeller is configured so that the radius r to the outer circumference of the impeller blade unit is smaller than the axial height h of the impeller. When an airflow that enters through the impeller opening is forced out towards outer periphery of the impeller blade unit, windage loss at the wall surface of the lower endwall portion of the impeller is reduced, which realizes high-efficiency cooling performance that complements motor performance.

Abstract: A bi-directional reversible submersible motor, which includes a housing having an inside bracket, two water guide plates fastened to the two distal ends of the housing and covered with a respective cap, a locating rod connected between the water guide plates, a sleeve affixed to the bracket and holding a winding, a magnetic shaft and fan blade assembly rotatably supported on the locating rod in the sleeve for rotating two fan blades to pump water when the winding is electrically energized, and a controller for controlling the supply of electric current to the winding to control the direction and time of rotation of the fan blades.

Abstract: A bearing assembly includes a bearing (10) having a bearing surface (16) defining a bearing hole (12) therein and a shaft (20) disposed in the bearing hole of the bearing. The bearing has an open end for the shaft insertion therethrough into the bearing hole along an axial direction of the bearing. The shaft defines a notch (24) in an outer periphery thereof, which is located corresponding to the open end of the bearing. A plurality of spiral grooves (228) are defined in the outer periphery of the shaft above the notch. A rotation direction of the shaft is the same as a spiral direction of the grooves during rotation of the shaft. A cover (50) covers the open end of the bearing and closely surrounds the grooves of the shaft.

Abstract: A motor includes a housing including separate motor and bearing cooling inlets. A motor is arranged within the housing and includes a stator and rotor assembly that is supported on air bearings. The motor cooling inlet is in fluid communication with the stator, and the bearing cooling inlet is in fluid communication with the air bearings. A vent is arranged in the housing and is common to the motor and bearing cooling inlets. The vent is in fluid communication with a low pressure side of a ram air duct. The bearing cooling duct is in fluid communication with a high pressure side of a ram air duct, such as through a reverse J-tube. A differential pressure between the high and low pressure sides moves cooling fluid from the bearing cooling inlet to the vent to cool the bearings.

Abstract: A downhole dynamic compressor comprises an electric motor having a stator 6 with stationary windings and an armature with permanent magnets 7 supported on gas bearings 9, 10 for rotation relative to the stator. The gas bearings 9 and 10 are arranged at the upstream and downstream opposite ends of the motor, respectively. The dynamic compressor has a bladed wheel 12 mounted on an overhanging end of the motor armature 7 that projects beyond the gas bearing 9 at the upstream end of the motor, whereby all the gas bearings of the compressor and the electric motor are arranged on the downstream side of the dynamic compressor.

Abstract: A magnetic floating shaft set is disclosed to include two guides kept apart from each other at a distance in such a manner that one guide is movable relative to the other guide to adjust the distance between the two guides, a shaft set in between the two guides with the two distal ends thereof respectively facing the two guides, a magnetic member mounted on the shaft, and a winding coaxially mounted around the shaft for generating a magnetic field to induce the magnetic member and to further cause floating of the shaft between the two guides and rotation of the magnetic member on the shaft.

Abstract: A blood pump device comprises a housing having a blood inflow port and a blood outflow port, an impeller having a magnetic body or bodies and rotated in a non-contact state in relation to the inside surface of the housing to feed blood, an impeller rotating torque generating section for attracting the impeller from the outside of the housing and rotating the impeller, and a non-contact type bearing mechanism enabling the rotation in the non-contact state of the impeller inside the housing. An impeller fixing member is detachably mounted to the housing and prevents the impeller from moving inside the housing, whereby the impeller can be prevented from moving inside the housing before use, and damage to the impeller or the housing inside surface can be avoided.

Abstract: A cooling device comprises a circulation passage through which a liquid coolant flows, and a pump provided in the circulation passage configured to circulate the liquid coolant along the circulation passage. The pump includes, (1) a pump casing including a pump chamber into which the liquid coolant flows, (2) an impeller mounted in the pump chamber to push out the liquid coolant from the pump chamber to the circulation passage, and (3) an injection portion provided in the pump casing configured to inject the liquid coolant to the pump chamber.

Abstract: Provided is a motor shaft supporting structure for reducing noises when a motor operates in a refrigerator. In the motor shaft supporting structure for a refrigerator, a bearing housing supports a motor shaft in an axial direction of the motor shaft. The motor shaft is coupled to a blower fan. A bearing is inserted in the bearing housing for rotatably supporting the motor shaft. An ethylene propylene diene monomer (EPDM) sheet is disposed on a portion of the bearing housing for supporting the motor shaft in the axial direction of the motor shaft.

Abstract: An electric fan includes a fan base (10), a bearing (40) and a rotor assembly (20). The fan base forms a central tube (11) receiving the bearing therein. The rotor assembly includes a fan hub (22), and a pivot axle (23) joined to the fan hub. The pivot axle pivotably extends into the bearing. A first and second locking rings (50, 70) are received in the central tube. Each of the first and second locking rings defines a central bore (52) therein. The pivot axle is engaged in the central bores of the first and second locking rings. The first locking ring is located at a top of the bearing and the second locking ring is located at a bottom of the bearing to prevent the rotor assembly from escaping from the bearing when the fan is operated.

Abstract: A motor structure resistant to liquid intrusion features two modules, the first having an electronically commutated external-rotor motor (20), which motor comprises an internal stator (22) that is arranged on a bearing tube (30) and is separated by a first air gap (24) from an external rotor (26; 92), which latter comprises a rotor cup (40) that is open at one end and is joined at its other end to a shaft (46) that is journalled in the bearing tube (30), further having a permanent-magnet arrangement (76), arranged at the open end of the rotor cup (40), for magnetic interaction with a second permanent-magnet rotor (92), forming part of the second module. The first module is separated from that second rotor (92) by a second air gap and forms therewith a magnetic coupling (94), so that a rotation of the permanent-magnet arrangement (76) brings about a rotation of that second rotor (92).

Abstract: A ring-shaped member is secured to a shaft of a motor between a portion of the shaft connected to a rotor and a sleeve accommodating the shaft and impregnated with lubricating oil. The ring-shaped member is coated with a repellent agent repelling the lubricating oil. An outer diameter of the ring-shaped member at its sleeve side, i.e., a first outer diameter is larger than that at the opposite side, i.e., a second outer diameter. A shaft-retaining portion is provided between the connected portion of the shaft and the ring-shaped member. A diameter of the hole is larger than the first outer diameter and smaller than the second outer diameter. At least one of the ring-shaped member and the shaft-retaining portion is elastically deformable.

Abstract: An easy-to-assemble electric motor (21) features an internal stator (50), an external rotor (22) having a shaft (34), which external rotor is configured as a rotor cup or bell (24) having an outer side and an inner side (25), a bearing tube (70) for receiving a bearing arrangement (60) journaling the shaft (34), which bearing tube (70) has a first end portion (71) facing toward the inner side (25) of the external rotor (22) and being formed with an inwardly protruding stop (73), the bearing tube having a second end portion (75) facing away from the first end portion (71) and being joined to a plastic part (80) that likewise forms an inwardly protruding stop (77) adjacent a second end portion (75), the bearing arrangement (60) being located in the bearing tube (70) in a chamber defined between said two inwardly protruding stops (73, 77).

Abstract: The compressor apparatus comprises a radial compressor (35) for the compression of a gas and also an electric motor (31) for driving the radial compressor (35), wherein the radial compressor (35) and the electric motor (31) are arranged in a pressure housing (1) which is provided with a gas inlet duct (2) and also a gas outlet duct (3), and also comprises an encapsulated apparatus (4) arranged in the pressure housing (1), the inner space of the encapsulated apparatus being fluid conductingly connected to a pressure reducing apparatus (37).

Abstract: A bearing of a water pump is adapted to be used with a washer and includes an approximately cylindrical body with an axial hole defined in its center. One end surface of the bearing, which faces the washer, has a nick for forming a water membrane so as to reduce friction and adhesion between the bearing and the washer.

Abstract: A method of manufacturing an impeller includes the steps of: (a) forming an impeller having a plastic disc body and magnetisable material distributed and encapsulated within the body; (b) testing the imbalance of the impeller; (c) removing plastic material from the impeller to compensate for the tested imbalance; and (d) magnetising the magnetisable material to have an annular array of alternating poles.

Abstract: A rotor is provided so that a rotor-side end part of a rotation shaft is rotatably supported by a bearing accommodated in a bearing accommodating part provided in a bottom part of a yoke in such a way as to project to a rotor side, and a part of an armature winding wound around a core surrounds the bearing accommodating part through an insulator.

Abstract: A hermetic electric compressor is capable of efficiently pumping up a necessary amount of lubricating oil even at low-speed rotation and has a simple constitution to provide an excellent workablity in assembling. The hermetic electric compressor includes an oil pump. The oil pump includes (i) a slanting channel formed in the lower portion of a main shaft and slanting from the lower portion to the upper portion thereof outwardly, (ii) a throttle formed at the bottom end of the main shaft and having an inlet port of diameter smaller than the section of the slanting channel at the center thereof, and (iii) a lower communicating passage for providing a communication between the bottom end of a spiral groove and the slanting channel. This constitution is capable of effectively lift the head of the lubricating oil.

Abstract: This compressor unit comprises a motor (34) and at least one compressor (44) comprising a driven shaft (54) driven by the rotor of the motor and bladed wheels fitted on the driven shaft (54), the assembly composed of the motor and the compressor being installed in a common casing (55) leak tight to the gas manipulated by the compressor unit. The rotor and the driven shaft are connected through a flexible coupling (72) placed in the casing.

Abstract: A coupling structure for a tandem motor includes two bearing sleeves formed with grooves thereon, a connector and elastic fasteners. The connector has a first end and an opposed second end, and each of the first end and second end is formed with at least one groove. A first elastic fastener is fit into the groove of the connector at the first end and received in the groove formed on one of the two bearing sleeve, and a second elastic fastener is fit into the groove of the connector at the second end and received in the grooves formed on the other bearing sleeve.

Abstract: A magnetic bearing assembly having a magnetic portion for simultaneously generating axially and radially magnetic forces and a bearing portion for supporting a shaft upon its rotation is disclosed. The magnetic bearing assembly according to the present invention can be utilized in a motor of a cooling fan to provide the substantially frictionless rotation and the precise position of the shaft. Thus, it requires no lubrication, results in less abrasion and produces low noise, all of which contribute to extend the operating life of the bearing.

Abstract: A heat-dissipating fan of the invention has an axle, a bearing, a rotor and a stator. The axle and the bearing are made of a ceramic material, and are located at a central location of the rotor and the stator. The bearing is a hollow cylinder integrally formed into a single body, and has a central hole and a recess at its bottom. The axle penetrates through the central hole of the bearing to contact the recess. A magnetic force center of the silicon steel sheet is at a level lower than that of the magnetic bar to generate radial and axial force components, allowing stable rotation of the rotor. The heat-dissipating fan of the invention provides advantages such as low friction, lower noise, low energy consumption, high performance and high stability.