Abstract: A rotary electrical machine (1) has at least one stator (23). The stator is provided with at least one radial channel (107) for ducting cooling air. The channel (107) extends between a first position (113) at or substantially near the rim (109) of a winding region of the stator (23) and a second position (119) at or substantially near the center (51) of the winding region. The machine (1) has cooling means (91-97) for causing cooling air to enter the radial channel (107) via the second position (119) and exit via the first position (113). The stator may have electrical windings arranged as coil sectors (183-197) disposed substantially equi-angularly in a generally circular pattern. At least some of the coil sectors are wound in a generally spiral fashion when viewed axially. A rotor (13), for the machine may have a plurality of equi-angularly spaced magnets (127), which are generally circular but with a cut-away portion, when viewed axially.

Abstract: To facilitate the fabrication work of a stator column assembly and improve full and wise use of resources, as well as to prevent contact accident between a mold portion of a stator column and a rotor shaft due to the thermal inflation.

Abstract: The PEC is utility device designed to convert intermittent pressure into electrical charges. It may be implemented in a variety of forms. The easiest to describe is the mechanical floor plate. It consists of depress-able track mounted plates with small barrel electrical generators attaches to the bottom and geared to turn downward step pressure into rotational energy for the generators. This implementation is inexpensive to manufacture, as it uses off the shelf components, and would be ideal in third world applications where components are difficult to obtain. It would be useful in animal movement applications, like the herding of livestock for transport or processing. The current generated is stored in a separate battery assembly, and the flooring is designed to lock together on all four sides with the electrical transport channel outlets available on all sides as well.

Abstract: A power apparatus in which a battery is connected to a dynamo to drive it as a motor and deliver energy to a spiral spring to wind-up the spring. When the spring has been wound to a particular degree a sensor disconnects the motor from the spring which now unwinds and delivers output power. A further sensor detects low charge state of the battery and during unwinding of the spring, some spring energy is delivered to the dynamo, now acting as an alternator, to charge the battery.

Abstract: A motor housing assembly includes a motor housing mounted to a gear housing and a brush holder assembly where the brush holder assembly is fixed in position by the junction between the motor housing and the gearbox. In one embodiment, a gasket is mechanically attached to the brush holder assembly via detents, and is compressed between the motor housing and gearbox when the two are assembled together.

Abstract: A magnetic device having a stator assembly having a magnetic flux return path comprising at least a pair of pole plates located a fixed distance apart from each other and at least one flux return strip pressed between each pair of spaced apart pole plates, and a rotor assembly having permanent magnetic material and being disposed for rotation relative to the stator assembly. Use of the flux return strip eliminates the need for a housing of ferrous material to complete the flux return path and facilitates flexible design of light-weight non-metallic housings and mounting systems or integral mounting to mating components.

Abstract: A motor/generator is provided with a stator (14) and rotors (2, 3). The stator (14) comprises a plurality of cores (11, 12) arranged on a circle. Each core (11, 12) has a base (11A, 12A) of a trapezoidal cross-section which increases a width in a direction away from the center of the stator (14). Deformation of the cores (11, 12) towards the center of the stator (14) is limited by retaining plates (18) each of which is engaged with the bases (11A, 12A) of adjacent cores (11, 12). The retaining plates (18) are formed to have a trapezoidal cross-section which increases a width in a direction towards the center of the stator (14). Rings (21, 22) are press fitted to an inner side of the both ends of the retaining plates (18). Preferably a reinforcing ring (25) is provided to support the inner periphery of the retaining plates (18).

Abstract: A small footprint vertical lift and rotary positioning stage comprises a bottom wedge and a top wedge, a linear bearing between the bottom wedge and the top wedge, cam grooves and cam surfaces for constraining the motion of the top wedge in a vertical direction, a brushless linear motor for moving the bottom wedge back and forth along a horizontal path raising and lowering the top wedge, a circular table rotatably mounted on the top wedge and having a first cylindrical flange extending downward from a segment of the circumference of the circular table, a bracket mounted on the side of the top wedge, the bracket supporting an upwardly extending second cylindrical flange coaxial with the circular table and the first cylindrical flange, and a brushless curvilinear motor between the first and second cylindrical flanges.

Abstract: A drive system having an electric machine, by which a drive shaft of a drive assembly is capable of being driven in rotation and/or electric energy is capable of being recovered during the rotation of the drive shaft. The electric machine has a stator arrangement and a rotor arrangement connected or connectable to the drive shaft for joint rotation about an axis of rotation. A positive guidance arrangement is provided via which the rotor arrangement and the stator arrangement are guided relative to one another when a relative axial movement is carried out for assembling or dismantling the electric machine.

Abstract: A transverse flux drive includes a first component and a second component which is rotatable with respect to the first component. A pair of transverse flux motor units are coupled between the first and second components. Each motor unit includes a plurality of U-shaped armature elements which are coupled to the first component and which enclose an circumferentially extending exciter winding. Each motor unit also includes a plurality of permanent magnet pole elements coupled to the second component. The pole elements of one motor are axially movable to attenuate the magnetic flux coupling between the elements of the motor.

Abstract: A rotary electromechanical device of the invention comprises a motor (A3) including a stator (3b) and a rotor (6a), a motor (B4) including a stator (4b) and a rotor (6b), and variable power supplies (2a, 2b) for driving the respective motors (A3, B4) independently of each other, wherein the motors (A3, B4) are arranged in series along the axial direction of a rotary shaft (5). Magnetic poles of the same polarity of the rotors (6a, 6b) are located at the same angular positions around the rotary shaft (5) while magnetic poles (+U1) of the stator (3b) of the motor (A3) and magnetic poles (+U1) of the stator (4b) of the motor (B4) are displaced from each other in the circumferential direction of the rotary shaft (5).

Abstract: A magnetic induction device having at least one secondary induction assembly including a secondary winding is mounted on a rotary element. A magnetic flux is induced the secondary induction assembly, causing an induced secondary alternating current in the secondary winding of the secondary induction assembly. The secondary alternating current is converting to direct current and is stored in an electrical storage device.

Abstract: A first motor/generator unit (10A comprises a first rotor (42) and a first stator (40) with a plurality of coils. A second motor/generator unit (10B) comprises a second rotor (43) and a second stator (41) with a plurality of coils. By properly determining the number of coils S1, S2 in the stators (40, 41), the number of pairs of magnetic poles P1, P2 in the magnet of the rotors (42, 43), and the number of phases M1, M2 in alternating currents driving the rotors (42, 43), and connecting a coil with a coil number j in a group number i of the first stator (40) with a coil with a coil number i in a group number j of the second stator (41), it is possible to suppress an ineffectual current generated when two motor/generator units (10A, 10B) are independently driven by the same inverter (32).

Abstract: An electric motor having a stationary annular stator with wound stator poles and a rotatably mounted rotor having annularly distributed permanent magnets or electromagnets of alternate polarity, wherein the stator is composed of a plurality of separate stator segments with their own, preferably three-phase current connections, wherein each stator segment is fed by way of the respective current connections from its own frequency converter.

Abstract: Rotary synchronous machine includes a stator and a rotor. The stator includes a magnetic field core and an armature core magnetically separated from each other. The rotor includes a plurality of magnetic substance segments which are magnetically separated from each other in a direction of rotation but are magnetically coupled with both of the magnetic field core and armature core. The rotor and magnetic field core are arranged to cause an axial thrust to the rotor depending on the intensity of electric currents passed through filed windings. Namely, the rotor and magnetic field core are arranged in such a manner that magnetic attraction (magnetic coupling) occurs between the rotor and the magnetic field core in a same direction as a rotational axis or at a predetermined non-normal angle relative to the rotational axis.

Abstract: In a starter-generator for a motor vehicle, having an electrical machine that can be coupled selectively to an internal combustion engine and/or a transmission of the motor vehicle, the electrical machine (9, 12) is accommodated in a shallow cylindrical housing (5), which on axial opposed face ends is provided with means (28) for securing it to the engine or to a housing of the transmission. This makes it possible to combine the engine, the starter-generator, and the transmission into a compact, linear group.

Abstract: An electric motor is fastened to a machine, such as a piston pump. For fastening the electric motor to a positioning device, the invention proposes embodying a motor housing with T-shaped fastening elements, whose crossheads are bent into a circle and which engage blind bores in the positioning device and are retained in the blind bores by a calk.

Abstract: Gas turbomachinery electricity generation apparatus includes a gas turbomachinery arrangement having an associated rotary drive take-off, an electricity generating arrangement which includes a first generator stage including a first generator rotor and generator stator arrangement; a second generator stage including a second generator rotor and generator stator arrangement, at least one of the first and second generator stage rotors is driven by the rotary drive take-off.

Abstract: A modular electric motor for use in a wellbore. The modular motor includes a plurality of modular motor sections. The modular motor sections being mechanically and electrically coupleable. At least one modular motor section having a rotor. The rotor of one modular motor section having a rotor being drivingly coupleable to the rotor of a second modular motor section having a rotor. Thus, a given motor may be assembled to a variety of desired lengths by connecting the appropriate number of modular motor sections.

Abstract: A control device for an object includes a first wheel and a second wheel that rotate in opposite directions on a shaft affixed to a frame. The first and second wheels have openings to accept magnets that are free to slide up and down in the openings. As the wheels rotate, the magnets are urged outwards due to centrifugal force. The wheels have titanium sleeves fitted around the outer surfaces of the wheels, which have openings smaller in size than the openings of the wheels, so as to maintain the magnets within the openings even as the wheels rotate. Solenoid stations are provided around the wheels, and as a result of magnetic pulses provided from at least one of the solenoid stations, in synchronism with rotation of the wheels, a magnet is urged inwards to a center of the wheel in which it is disposed, to thereby result in a force vector that causes movement of the frame to thereby control the object.

Abstract: A compound motor comprising a plurality of motors, each motor comprising a rotating member that is rotatably supported and a stator winding, wherein all rotating members share the same axis of rotation and the stator winding of each motor has a different number of poles.

Abstract: A rotational power converter is composed of a stator fixed to a cylindrical housing and a first rotor and a second rotor rotatably supported in the housing. The first rotor is driven by an internal combustion engine, and electric power is supplied to the stator from a battery, forming a rotating magnetic field in the stator. Rotational power is electromagnetically transferred from the first rotor to the second rotor that is connected to driving wheels of a vehicle. The amount of the rotational power of the second rotor is adjusted by controlling electric current supplied to the stator. The battery either supplies power or receives power according to the amount of the rotational power of the second rotor. Since the electric current is supplied only to the stator fixed in the housing, no electric feeder having slip-rings and brushes is necessary. Accordingly, the rotational power converter is made small in size and its reliability is improved.

Abstract: In a plant comprising one or more electric machines constructed with insulated conductors and connected for heavy current via insulated conductors, the magnetic circuit in at least one of these electric machines is connected directly to a high supply voltage of 20-800 kV, preferably higher than 36 kV. The insulation of the electric machine is built up of a cable (6) placed in its winding and comprising one or more current-carrying conductors (31) with a number of strands (36) surrounded by outer and inner semiconducting layers (34, 32) and intermediate insulating layers (33). The conductors (31) may be group-wise connected in parallel and semiconducting layers are therefore not required around every conductor in the group.

Abstract: The invention comprises a motor driven machine, the machine such as a lathe, drill, router, saw, or shaping tool includes a machine spindle and a switch reluctance motor having a motor spindle. The construction is such that the longitudinal axis of the motor spindle and the longitudinal axis of the machine spindle lie on substantially the same axis. In one form of the invention the machine spindle and motor spindle can be unitary.

Abstract: The invention discloses a motor device comprising a pair of motor units and a driven member meshed with rotary gears of the pair of motor units to drive the driven member, the motor units each comprising a rotary magnet that is cylindrical and magnetized so as to have different magnetic poles in turn along the circumferential direction, a rotary gear having a plurality of teeth, the rotary gear rotating about the rotation axis of the rotary magnet together with the rotary magnet, and a stator member having a plurality of outer magnetic poles that are arranged on the outer periphery of the rotary magnet and a plurality of inner magnetic poles that are arranged on the inner periphery of the rotary magnet and are opposed to the outer magnetic poles, the plural outer magnetic poles and the plural inner magnetic poles being excited by a coil.

Abstract: The present invention relates to em electric motor assembly (1) comprising a main electric motor (2) and a coupled electric starter motor (3). The electric starter motor (3) may, for instance, be coupled to the rotation axle (4) of the main electric motor (2). In this way, the electric starter motor (3) will be actuated to accelerate the main motor (2) up to a nominal rotation, after which the main motor (2) will be ready to be actuated, and, since it will already be in motion, the current required for accelerating it up to its nominal power will lie within the ranges permitted by the electricity supply companies In this way, it is possible to actuate a motor having a power rating of, for example, 50 HP, with low current peaks.

Abstract: An electric machine or assembly 10 including a generally cylindrical ferromagnetic housing 12, two substantially identical and opposed stator assemblies 14, 16 which are fixedly mounted within housing 12, a generally disc-shaped rotor 18 which is disposed between stator members 14 and 16 and which is coupled to a rotatable shaft 20, and a generally circular and stationary field coil 22, which is fixedly mounted within housing 12 and is controllably and selectively engergizable to vary the output voltage, power, or torque provided by assembly 10.

Abstract: A conveying device in which a conveying arm assembly can be quickly set in a conveying position and can be rapidly stabilized in the conveying position is disclosed. The conveying device comprises a conveying arm assembly, a fixed shaft, at least one set of hollow operating shafts which are necessary for controlling an operation of the conveying arm assembly, and a motor provided between the fixed shaft and each of the operating shafts. The one set of operating shafts are attached to the fixed shaft such that they can be rotated coaxially with respect to the fixed shaft outside fixed shaft and are arranged in an axial direction of the fixed shaft. The motor comprises a stator provided on the fixed shaft and a rotor provided on each of the operating shafts such that it is opposed to the stator on an outer peripheral side of the stator.

Abstract: The electric machine, particularly a three-phase generator, has an exciter machine (26) in the form of a claw pole machine which supplies the exciter current necessary for the generator. The exciter machine is located to the side of the generator and has substantially smaller dimensions than the latter. At claws (28, 29) of the stator (25) which face the armature (32) of the exciter machine, permanent magnets (39) are located in the leakage flux area between the claws. Unwanted leakage fields are contained in this way.

Abstract: The invention reduces ripples of a rectified output caused by setting a neutral-point diode and improves a generated output by preventing excessive heat generation. First and second stator windings are configured by Y-connecting a pair of three windings on a common stator core so as to have a phase difference of 30° from each other. A rectifier device includes a first and a second rectifier for rectifying and outputting a phase current derived from an end of each of the windings and a neutral-point current derived from a neutral point of each of the windings. Outputs of each of the rectifiers are synthesized to generate a synthesized output at an output terminal. The first and second rectifiers have rectifying diodes and neutral-point diodes disposed on a common heat sink.

Abstract: A twin-shaft concentric motor includes first and second stators arranged concentrically to each other; and first and second rotors formed between the first and second stators, the rotors being rotatable independently of each other. The twin-shaft concentric motor may also include first and second stator partition walls and first and second rotor partition walls for maintaining a vacuum side and an atmospheric side separated, respectively, so that the stators are located under atmospheric pressure while the rotors are located under vacuum pressure.

Abstract: An electric compressor includes a compression mechanism and an electric motor. The compression mechanism compresses gas. The electric motor has a rotary shaft that is coupled to the compression mechanism. The compression mechanism and the electric motor are integrally assembled. The electric motor is a ring coil type motor in which a coil is wounded in the circumferential direction of the rotary shaft.

Abstract: A structure for an a.c. electrical machine and method of transducing power between two different systems. The machine comprises two electrically balanced transformers which are generally, but not exclusively, three phase. Initially the transformers are in balance and no currents flow in the secondary windings of the transformers. An electrical or mechanical imbalance is introduced between the transformers causing current to circulate in the secondary windings. The secondary windings in one embodiment are provided on a rotor in which case the currents induced in the secondary windings cause a torque to be exerted on the rotor. It is also possible to arrange the machine as a transformer or alternator.

Abstract: A stepping motor 10 having a configuration which includes: a rotor 14 constituted by a rotor magnet 14b magnetized circumferentially; a stator 13 constituted by a plurality of phases of stator yokes 16a to 16h arranged side by side in an axial direction of the stepping motor so as to surround the rotor, and coils 17a to 17d wound in coil winding portions defined by the stator yokes; an armor member 11, 12 for holding the stator yokes with respect to the axial direction of the stepping motor; and each phase of the stator yokes being constituted by a pair of stator yokes on which magnetic pole teeth of plural phases arranged annularly are combined alternately; wherein the stator yokes are arranged so that every two phases of the stator yokes are paired to form an even number of sets of stator yokes; wherein two phases a and b and c and d in each set of the stator yokes are reverse to each other; and wherein coils 17a and 17b and 17c and 17d provided on the two phases of stator yokes in each set are connected to

Abstract: A bracket assembly and method for coupling a motor to a hoist machine comprising an adapter plate for coupling to a motor face and sized to cover the face of the motor and accommodate an existing motor register on the hoist machine, a drum flange member coupled to the hoist machine to reduce vibrations, the drum flange member having a central cavity for receiving the motor shaft, a second flange member having a bushing sized to the motor shaft, and a coupling plate positioned between the first and second flange members, the coupling plate made of a resilient material such as a plastic. Each of the first and second flange members and coupling plates have hole portions radially positioned and in alignment with one another, the drum flange having holes formed therein for accommodating a connecting rod such as a bolt to securely fasten the drum flange to the drum brake of the hoist machine.

Abstract: A motor comprising two or more rotors (20, 30) rotated by means of a common power supply (6), each rotor (20, 30) having a plurality of poles (22, 32) and being associated with a stator (16, 26) having a plurality of poles (18, 28), wherein the arrangement of rotor poles (22, 32) and stator poles (18, 28) is different for each rotor 920, 30) so that the rotors (20, 30) rotate at different speeds when the common power supply (6) is applied.

Abstract: An uncluttered secondary induction machine (100) includes an uncluttered rotating transformer (66) which is mounted on the same shaft as the rotor (73) of the induction machine. Current in the rotor (73) is electrically connected to current in the rotor winding (67) of the transformer, which is not electrically connected to, but is magnetically coupled to, a stator secondary winding (40). The stator secondary winding (40) is alternately connected to an effective resistance (41), an AC source inverter (42) or a magnetic switch (43) to provide a cost effective slip-energy-controlled, adjustable speed, induction motor that operates over a wide speed range from below synchronous speed to above synchronous speed based on the AC line frequency fed to the stator.

Abstract: A combined power driven device is made up of three layers, each of the three layers forming an electromechanical structure such as a stator or an armature. One of the three layers serves as a common magnetic structure for interaction with the electromechanical structures formed by the other two layers and the three layers may be mechanically coupled with each other, a load, and/or an active power source to provide either generator or motor functions, or a combination of generator and motor functions.

Abstract: A first motor/generator unit (10A, 11) comprises a first rotor (42, 42B, 42C) and a first stator (40, 40A, 40B, 40C) provided with a plurality of coils. A second motor/generator unit (10B, 11) comprises a second rotor (43, 43B, 43C) and a second stator (41, 41A, 41B, 41C) provided with a plurality of coils. Providing that the number of coils in the first stator (40, 40A, 40B, 40C) is S1, the number of pairs of magnetic poles in the magnet of the first rotor (42, 42B, 42C) is P1, and the number of phases in a first alternating current which drives the first rotor (42, 42B, 42C) through the coils of the first stator (40, 40A, 40B, 40C) is M1, the coils of the first stator (40, 40A, 40B, 40C) are divided into K1 groups satisfying the equation K1=S1/M. The coils in each group are mutually connected by either a Y connection or a delta connection.

Abstract: In a state that a wafer stage is not positioned in the center of the Y-direction traveling range, thrusts Fa, Fb supplied from a pair of linear motors to a Y-direction stage are made different and the Y-direction stage is moved in the X direction so that moments Ma, Mb about the centroid of the Y-direction stage by the thrusts Fa, Fb cancel each other. Since the moments Ma, Mb about the centroid generated by the thrusts cancel each other and the thrusts do not act as forces for rotating the Y-direction stage, the Y-direction stage is not deflected in a yawing direction. Such a stage device as constructed above can prevent deflection in a yawing direction due to displacement of the centroid position of an object to be positioned or a stage and precisely move the object to be positioned to a target position.

Abstract: In a motor having a motor body and a speed reduction devise composed of gear housing, a worm wheel, worm shaft with a worm, and first and second bearings rotatably supporting the worm shaft on opposite sides of the worm, the first bearing on a side of the motor body inclines a given angle to a bending side of the worm shaft, when the worm shaft is bent by an overload transmitted thereto via the worm wheel.

Abstract: The method and apparatus for supplying power to a rotary element by magnetic induction. A magnetic induction device having at least one secondary induction assembly including a secondary winding is mounted on the rotary element. A magnetic flux is induced the secondary induction assembly, causing an induced alternating current in the secondary winding of the secondary induction assembly. The secondary alternating current is converting to direct current and is stored in an electrical storage device. A rotary cathode plater is disclosed as a particular application of the apparatus by which power is transferred to a storage battery or high capacity capacitor, without the use of wires.

Abstract: A starter generator for an internal combustion engine serving as a starter motor when the internal combustion engine should start and as a generator after the internal combustion engine starts and comprising a magnet rotor and a stator having a plural of coils, a plural of switch circuits to switch a current flowing through the coils and a switch controller to control switch elements of the switch circuits whereby the current flows through all the coils by controlling the switch circuits in accordance with a position of the rotor when the engine should start to thereby produce a large torque and the current flows through one or some of the coils via a rectifying circuit of rectifying diodes provided in some switch circuits after the engine starts to thereby charge the battery.

Abstract: A revolving magnetic field type motor has a rotor and a stator. The rotor has a plurality of permanent magnets. The permanent magnets defines a plurality of rotor magnetic poles. The number of the rotor magnetic poles is “P”. The rotor has a plurality of blocks aligned in the rotor's axial direction. The number of the blocks is “m”. Each block has a set of the rotor permanent magnets. One set of the permanent magnets is offset relative to an adjacent set of the permanent magnets by a predetermined offset angle in the rotor's rotational direction. The stator has a plurality of coils, the coils defining a plurality of stator magnetic poles around the axis of the stator, the number of the stator magnetic poles being “T”. The predetermined offset angle is selected from within a range from about zero degrees/((m−1)×n) to about 22.5 degrees/((m−1)×n).

Abstract: This invention relates to an electrical rotating actuator for forming the shed in a weaving loom, particularly for controlling the harness cords of a weaving system of the Jacquard type or the frames of a dobby, comprising a rotor and at least one stator whose armature is formed by a stack of metal plates, characterized in that the stator is formed by at least two stator elements disposed side by side along the axis of rotation of the rotor, each stator element comprising two zones for reception of a winding of electrically conductive wire, the metal plates of each zone disposed opposite one another being mated.

Abstract: Apparatus for generating rotating motion includes one or more electrical motors or generators arranged in a circle about a central shaft. The motors or generators are attached to a rotatable plate, which in turn is attached to the central shaft. The shafts of the motors or generators are belt connected to a fixed core. Operation of the motors results in rotation of the plate and the central shaft, which further results in the motors or generators orbiting around the central shaft.

Abstract: An electrical generator has at least one rotating ring of field magnets which produce a circular array of magnetic fields, and a ring of generator output coils which are in the magnetic fields. The field magnets are permanent magnets or electromagnets. The generator output coils are movable in a displacement path toward and away from a null position at which they are exposed to zero net flux from the magnetic fields. Movement of the coils by an actuator varies the amplitude of the voltage induced in these coils by the rotating field magnets. The actuator is energized by an alternating current to create a mechanical oscillation of the generator output coils in their displacement path. The coils provide a raw amplitude-modulated signal that has a carrier frequency which is a function of the rotational velocity of the field magnets and a modulation frequency that is proportional to the mechanical oscillation of the generator output coils.

Abstract: A DC motor has a housing having an air gap and a stator coil is positioned in the air gap. First and second permanent magnet rotors are coaxially arranged to one another in the housing on opposite sides of the air gap. The first and second permanent magnet rotors are mounted in the housing without being mechanically connected to one another. In another embodiment, a flat stator coil is provided. At least one permanent magnet rotor has an axially magnetized annular rotor magnet, a plastic part as a support for the rotor magnet, a shaft mounted in the plastic part, and a soft magnetic ground element snapped into the plastic part. The rotor magnet is fastened to the soft magnetic ground element. In another embodiment, a housing having first and second cup-shaped housing parts is provided. The first housing part has a first bottom and the second housing part has a second bottom. The first and second bottoms form an air gap therebetween. A flat stator coil is positioned in the air gap.

Abstract: A long electrical motor mainly for submersible use having a high efficiency, being mechanically stable, capable of being assembled under low time consumption at low costs, and which is easy to maintain and repair. The long motor has a rotor divided into sections with at least one low friction bearing arranged between the sections and in each end of the long motor. A stator is stacked continuously past internal bearings using thin sheets of metal discs between the bearings. Each disc in the bearing pedestal is significantly thicker than the common stator discs and is made of paramagnetic metal with good heat transfer properties. The inner diameter of each disc in the bearing pedestal is smaller than the inner diameter of the common stator discs so that a bearing inserted into the bearing pedestal is held by a tight fit. The inner diameter of the bearing fits tightly to the axis of the rotor and slots for the stator windings in all metal discs are radially open towards the rotor.

Abstract: In a preferred embodiment, an actuator, including: a shaft (34); a solenoid (24), having a coil (40) and a core (42), disposed at a first selected position on the shaft, with the core being fixedly attached to the shaft such that energization of the coil will cause the shaft to move axially; and a rotary motor (22), having a stator (30) and a rotor (32), disposed at a selected second position on the shaft, with the shaft passing through the rotor, an external surface of the shaft and an internal surface of the rotor having complementary engaging surfaces such that rotation of the rotor will cause rotation of the shaft and axial motion of the shaft will be isolated from the rotor.