Abstract: A direct current motor having one or more armatures supported between magnetic pole plates having pairs of pole pieces extending, in diametric opposition with respect to the periphery of an armature between the plates adjacent the perimeter of the armature or armatures, and is energized by direct current through one or more iron coil cores interposed between and connected with the magnetic pole plates. Wiring and electrical current controls connect a DC source to the coils and armatures for selectively operating the armatures and providing a selected torque with a minimum of ampere drain from the DC source.

Abstract: In a stator-excited synchronous machine with laminated sector stator elements (SS1 or SS2), which are arranged one behind another at an axial distance and are winding-excited by in each case one excitation winding part (EW1 or EW2) of opposite polarity, the operating efficiency can be increased with low outlay when a permanent magnet arrangement (M) having a magnetization opposing the winding excitation in the sector stator elements is provided in the axial spacing chamber between the sector stator elements (SS1 or SS2); in order to lock the position of the magnet arrangement (M), the facing laminations of the magnet arrangement (M) have bent-away tongues (Z) gripping radially from below.

Abstract: An electromagnetically actuated friction welder produces orbital motion at interfaces between parts (usually of thermoplastic material) to bond the parts by fusion generated by friction. This welder can also be operated alternatively to produce reciprocating vibratory forces thereby providing flexibility as to the selection of an orbital or reciprocating mode, depending upon the joint to be welded. The velocity of motion is controllable preferably around the resonant frequency of the driven structure by adjusting the frequency of the AC power which operates the electromagnetic drive motor of the welder. A plate which carries one of the parts to be welded and which is driven is flexurally mounted for movement in an orbital plane or planes containing the interfaces without substantial tilting by an array of stiff members, such as rods, located around the drive motor, attached to the plate at one end and to a tubular structure at the opposite ends thereof.

Abstract: A rotary transformer having a rotor assembly mounted on a shaft and a plurality of associated cooperative stators rotatably mounted about the rotor assembly. The stators are angularly adjustable, relative to each other, about the axis of the shaft. Electrical power is delivered to one of the stators (the primary stator), which functions as a primary of the transformer. The remaining stators (secondary stators) function as a secondary of the transformer. The relative angular orientation between the secondary stators determines the magnitude of the output voltage from the secondary stators.

Abstract: A permanent magnet type stepping motor comprising first and second stator assemblies arranged coaxially about a longitudinal axis. Each assembly includes first and second ring-shaped stators made of magnetic material. The first ring-shaped stator has a central portion with an opening therein, an annular yoke surrounding the periphery of the central portion and a plurality of pole pieces distributed about the circumference of the opening and extending toward a plane transverse to the axis. The second ring-shaped stator has a central portion with an opening therein, an annular substantially planar yoke surrounding the periphery of the central portion and a plurality of pole pieces distributed about the circumference of the opening and extending away from the transverse plane so as to interleave with the pole pieces of the first stator. The central portion of the second stator protrudes from the plane of the yoke in a direction away from the transverse plane.

Abstract: The invention relates to a drive unit for a double fan consisting of two external rotor motors (1, 2) arranged alongside each other on a common motor shaft (3), wherein the external rotor motors (1, 2) are arranged with respect to each other in such a way that the poles of the stators (12) of the two motors (1, 2) and the poles of the rotors (7) of the two motors lie in mirror image symmetry with respect to each other with reference to a dividing plane X--X running between the two external rotor motors (1, 2) at right angles to the motor shaft (3).

Abstract: A permanent magnet motor having a plurality of armatures supported between magnetic pole pieces energized by one or more permanent magnets interposed between the magnetic pole pieces. Wiring and electrical current controls connect a DC source to the armature commutators for selectively operating the armatures at a predetermined rpm and providing a selected torque with a minimum of ampere drain from the DC source.

Abstract: A robot system with robot specific effects. Reconstructable for other fields of activities with few manipulations by the users themselfs. This objective is achieved in accordance with the present invention by standard robot-block parts of nearly the similar design for the installation of multiblock-robots with self operating walk, drive and manipulation faculties, with horizontally and vertically fitting, rotation flange plug connections, with turntables and driving motors and with current and communication channels which are leading through the center of the rotation plug connections and which provide current and communication supply lines and current and communication control lines. These lines are leaded to inside and outside slip-ring and induction units and to equipment components, composed of accumulators, sensors and electronic boards inside the block chamber.

Abstract: An electrical machine has a surface-cooled stator having two stator plate stacks provided with slots and two stator windings arranged one after the other in an axial direction and inserted in the slots of the stator plate stack, a drive shaft, two pole systems cooperating with the stator windings, a metal housing arranged so that winding ends of the stator windings project outwardly beyond the metal housing and the two plate stacks are enclosed by the metal housing and fitted in the latter so as to conduct heat. The two stator plate stacks are offset relative to one another by half a slot spacing and, together with the winding ends of the stator windings are embedded in heat conducting plastic to form a prefabricated construction unit.

Abstract: In the case of a spinning or twisting machine, it is provided that the spindles are each driven by separate electric motors which, together with their bearings, are arranged in a spindle rail constructed as a longitudinal duct, the stators and the rotors of the electric motors being disposed in the longitudinal duct in an exposed manner.

Abstract: An improved electric propulsion motor for marine vehicles. The motor has an axial gap design with a disk-shaped rotor and two disk-shaped stators. Within the large, open diameter of the motor a sound isolation coupling is disposed between two annular plates that connect the rotor to the propeller shaft. Circumferential thrust bearings counter and distribute electrical and mechanical forces in the motor to maintain the position of the rotor relative to the stators. A journal bearing supports the rotor. Noise reduction is greatly enhanced by the implementation of staggered stators, skewed stator slots, skewed field poles and a current control system that compensates for torque pertubations that are a repeatable function of shaft angle.

Abstract: The present invention is a lateral electric motor which can be driven in a single stage drive mode, a two stage drive mode or any other multiple drive stage mode. The main components of the lateral electric motor include permanent magnet poles mounted within a disk rotor which is positioned axially along a shaft and in between a first stator housing assembly and a second stator housing assembly. The first and second stator housing assemblies include wound armature coils mounted to lamination blocks and positioned to face opposite the permanent magnet poles. Each stator is configured with a first segment comprising a plurality of armature coils connected in series wherein the first segment is connected in parallel to a second segment through a switching device to a power supply. With this type of configuration the first and second stator housing assemblies can be further configured to either individually drive the lateral electric motor or be connected to drive the electric motor simultaneously.

Abstract: A direct current motor having a plurality of armatures supported between magnetic pole pieces energized by direct current through one or more iron core coils interposed between the magnetic pole pieces. Wiring and electrical current controls connect a DC source to the coil or coils and armatures for selectively operating the armatures at a predetermined rpm and providing a selected torque with a minimum of ampere drain from the DC source.

Abstract: An adjustable speed drive system is provided which employs a unique induction machine which includes a rotor assembly mounted on a shaft, and associated cooperative first and second stators. The two stators are angularly adjustable, relative to each other, about the axis of the shaft. The net excitation of the rotor and thus the operating point of the machine on the torque-speed curve of a load on the shaft of the machine is a function of the relative angular displacement of the two stators. A third stator may be employed to enhance the efficiency of the machine by feeding excess rotor power back into the power line.

Abstract: An inductance machine having a rotor assembly electromagnetically coupled to first and second synchronous magnetic fields. The first and second synchronous magnetic fields have a relative angular displacement about the rotor axis which may be adjusted.

Abstract: An air-cooled ac generator arrangement is rearranged to take advantage of otherwise wasted space within the generator. The permanent magnet generator is moved to the drive end of the rotor where it is placed under the drive end side winding of the main armature. The permanent magnet generator field now obstructs the passage of air to the drive end bearing so a comparatively small air impeller is added in the otherwise void space between the permanent magnet generator and the main field. Ports are also added to the permanent magnet generator field hub to provide for the required air flow.

Abstract: The phase difference between the pole teeth of a first stator and the pole teeth of a second stator is set to 30-80 degrees or 100-150 degrees in electrical angle, whereby the magnitude of combined torque of the torque generated by the pole teeth of the first stator and the torque generated by the pole teeth of the second stator becomes larger when the step number is odd and becomes smaller when the step number is even. Accordingly, when the number of steps for one motion is an even number at all times, the starting torque can be increased and the settling torque can be decreased.

Abstract: A plurality of identical modules are serially connected together with each module including a base plate and a top plate interconnected by a universal joint assembly so that the top plate is adapted to pivotally nutate around the base plate to describe a cone in space. An array of twenty-four electromagnets, sequentially energized in sets of three, are arranged in a ring around the periphery of the base plate. Selective energization of the eight sets of electromagnets causes the rim of the top plate to be magnetically attracted to the energized electromagnets. The tilt of the top pivot plate is detected and controlled over a range of 360.degree., thus permitting a series string of modules to assume any desired elongated configuration.

Abstract: A system for supporting a rotor without contact with a stator comprising a magnetic bearing apparatus mounted on the stator and including a controlling magnet means fixed to the stator, a non-controlling magnetic pole fixed to the stator, a biasing magnetic poles sandwiched between the controlling magnet and the non-controlling magnetic pole, and a rotor magnetic pole fixed to the rotor to enable the magnetic path of a biasing flux to run in a plane which includes the longitudinal axis of the stator. The non-controlling and rotor magnetic poles may have teeth facing each other.

Abstract: An auxiliary driving device being attached to a primary driving device of a rolling door and including a gear engaged with a gear wheel of the primary driving device, a motor having an axle, a lower disc with a pinion slidably engaged on the axle, a spring biasing the pinion and the lower disc upward, an upper disc disposed above the lower disc, three balls engaged in the recesses formed in the discs, the pinion moves downward to engage with the gear when the first motor is energized so that the spindle can be driven to rotate by the motor.

Abstract: A stepping motor for a timepiece is constituted by a rotatable rotor magnet on an outer surface of which magnetic poles having different polarities are alternately formed, and two stator assemblies, each including a pair of stators opposing around the rotor magnet to have a gap and having stator magnetic pole portions, and an excitation coil for exciting the pair of stators, for supplying currents to the excitation coils to rotate the rotor magnet. The two stator assemblies are disposed to be separated by a predetermined distance in an axial direction of the rotor magnet, so that stator gap central lines of the two stator assemblies cross each other at an angle of 90.degree. when viewed from the axial direction.

Abstract: A unique steer/drive control system is featured for steering a material handling vehicle by the use of directly coupled traction and steering motors. The steering motor is fabricated as a hollow shaft dc motor, whose inner ring represents the rotor, and whose outer ring represents the stator. The stator is connected to a frame of the vehicle carrying the steering and drive wheel. The rotor is integrally connected to the traction motor that drives the steering and drive wheel. A hand operated steering mechanism rotationally guides the vehicle. A steering angle sensor determines the difference between actual and desired heading of the steering and drive wheel. The steer/drive system utilizes the sensed difference, and generates a signal for controlling the heading of the steering and drive wheel.

Abstract: An electrical machine, according to the transverse flux principle, is constructed such that the magnetic flux flows in paths perpendicular to the direction of rotation of the rotor. The number of stator elements is double the number in the conventional transverse flux machine making this number equal to the number of rotor bars provided with permanent magnets. All the stator elements have the same shape, but are alternately turned 180.degree. with respect to the permanent magnet axis. Further, the permanent magnets of the adjacent rotor bars are of opposite polarity. Such a machine has almost twice the power of the conventional transverse flux machine of the same volume, and also has higher efficiency since the inactive amount of copper has been reduced. This machine can be designed as a generator or a motor, and for multi-phase operation.

Abstract: An ac generator system for a motor vehicle has a first voltage generating device (115-119) for producing a first output voltage and a second voltage generator device (105-109) for producing a second voltage, the second voltage being a higher voltage than the first voltage, the second voltage being electrically floating. In one embodiment the first and second voltage generating devices comprise an armature winding within which is rotatably mounted a respective field winding and a rectifier for producing a dc voltage from at least one of the armature windings. In another embodiment the second voltage device is a transformer and in a third embodiment the second voltage device is formed by a transformer and a pulse width modulator. In a fourth embodiment the second voltage device is formed by an inverter and in a fifth embodiment two armature windings are provided about a common field winding.

Abstract: A brushless electrical power generating system (10) in accordance with the invention includes a main generator (16) having a rotor (30) on which is wound a field winding (32) and a stator (112) on which is wound a winding (36) for producing an alternating current electrical output having at least one phase; an exciter (14) having a rotor (24) mounted coaxial to the rotor of the main generator and a stator (110) on which is wound a stator winding (18) and an electrical field shield (40) disposed between the stators of the exciter and the main generator for shielding the winding of the stator of the main generator from an electric field produced by the winding of the stator of the exciter whereby capacitive coupling of any electrical noise present within the current flowing in the stator winding of the exciter to the alternating current electrical power output is reduced.

Abstract: A combined linear-rotary direct drive step motor, having a rotary section and a linear section in a single housing, comprising a cylindrically shaped variable reluctance linear step motor; a modified hybrid permanent-magnet rotary step motor; and a common shaft shared by said linear step motor and said rotary step motor. The teeth of the rotary motor are circumferentially spaced around the stator pole faces and rotor; while in the linear portion of the motor, the teeth are longitudinally spaced along the face of the stator poles and rotor. Except for the teeth, the shape of the stator poles in the rotary and linear sections are identical. The laminated stators and rotors reduce eddy current losses at high stepping speeds. The stator coils of both motor sections are separate and can be energized independently allowing any combination of rotary or linear motion. According to alternate embodiments of the invention, the rotor is fabricated from stacked laminations, in a waffle board like configuration.

Abstract: An induction motor, including a single rotor formed in one-piece and first and second stators disposed side by side, has a phase changing device for varying the phase difference between the rotational magnetic field generated by the first stator and that generated by the second stator. The phase changing device comprises at least first and second short-circuiting switches for short-circuiting or disconnecting the series-junction nodes of the stator windings. The first switching produces a configuration intermediate to series delta and parallel Y (Wye), and the second completes the transformation from delta to Y. The motor presents three different torque curves suitable for starting operation, intermediate speed operation and normal or steady-state operation by the switching operation of the first- and second-switches.

Abstract: An electric motor suitable for incorporation in pipestacks for drilling and pumping applications has a drive shaft (4) carrying spaced rotor discs (6) driven by annular stator windings (7) carried by the motor housing wall. The windings (7) are organized as linear motors operating on a circular path and provision can be made for energization of the windings so as to cause axial movement of the shaft, for hammering or braking action. The shaft (4) can be tubular to provide a passage for drilling mud, or for a fluid being pumped.

Abstract: A motor-drive industrial robot which can be used as a painting robot is mainly constructed by a direct-drive motor, a fixed portion such as a base, and a movable portion such as a rotary table, an arm etc. The direct-drive motor for driving the movable portion is constructed by a rotor and a stator. Preferably, the stator is attached to the fixed portion, while the rotor is attached to the movable portion. In order to avoid the generation of sparks in the flammable atmosphere, this robot is designed as the explosion-proof construction, so that the protective gas ie enclosed within the direct-drive motor. This protective gas is supplied into an annular space formed between the rotor and stator via a through hole formed through the stator or rotor. In addition, this annular space is sealed such that the protective gas is not leaked from the direct-drive motor.

Abstract: In order to improve a machine tool with a motor spindle, including a main motor integrated into a work spindle coaxially with the spindle axis, the main motor, for its part, comprising a rotor and a stator, and with a cooling device for supplying cooling surfaces of the main motor with a gaseous coolant, so that simple and effective cooling of the main motors of the motor spindles is possible, it is proposed that the stator be comprised of stator plates which, for their part, form cooling surfaces, and that the gaseous coolant be conducted directly along the cooling surfaces of the stator plates.

Abstract: A structureborne vibration-compensated motor arrangement includes a pair of twin AC motors supported by a rotatable shaft structure and a stationary outer housing. Each motor includes an annular stator core structure and an annular rotor field structure. The stator core structure is mounted by an annular stator support member which, in turn, is stationarily supported by the outer housing. The rotor field structure is mounted by an annular rotor support member in spaced relation, either axially or radially, from stator core structure. The rotor support member, in turn, is mounted to the rotatable shaft structure for rotation therewith.

Abstract: An induction motor including a single rotor formed in one-piece and first and second stators disposed side by side has a phase changing device for varying the phase difference between the rotational magnetic field generated by the first stator and that generated by the second stator. The phase changing device comprises a first-connection changing switch for making the interconnection of respective stator windings of the stators the first series delta-connection in which the phase difference is 0.degree. when it is in its closed-state and a second-connection changing switch for making the respective stator windings the second series data-connection in which the phase difference is 120.degree. when it is in its closed-state. When both the first- and second-connection changing switches are closed, the interconnection of the stator windings becomes a parallel Y (or star)-connection in which the phase difference produced is 60.degree..

Abstract: A drive system for a pump/compressor which feeds a pneumatic circuit of a portable waste water sampling device, and comprising individual electric motors (20) each operating at 12 volts and drawing a current no greater the 350 mA at 2.5 w, the motors driving a common pinion (23) with an output shaft (24) for connection to the pump/compressor. The use of a number of low capacity drive motors, which together provide sufficient torque to drive the pump/compressor, avoids the danger of spark generation, particularly in a potentially explosive environment such as may be found below ground. Since the motors are small they may be mounted conveniently within the sampling equipment, taking up no more space than would be occupied by a single motor of larger capacity.

Abstract: A drive mechanism is redundantly equipped with two electric motors so that the second motor can take over the drive function if the first motor should fail, for example for moving equipment in or on a spacecraft. Both electric motors are connected to a common drive shaft. A coupling device makes sure that the defective motor is decoupled from the drive train.

Abstract: Potentially very high power ratings can be achieved from rotary electrical generators in which permanent magnet rotor stages using modern high intensity magnetic materials, for example cobalt samarium or neodymium boron iron. The machine described comprises a plurality of axial field rotor stages each comprising a plurality of magnet segments arranged around a driven hub in a pre-stressed assembly in which encompassing hoop means exerts sufficient compressive stress on the magnets and hub assembly to counter centripetal forces generated by speeds of up to 100,000 rpm. Alternative methods of stressing the hoop means is described.

Abstract: An electric motor drive system having a first electric motor, a first drive shaft to which the first electric motor is coupled, a second electric motor having a higher power rating than the first, a second drive shaft to which the second electric motor is coupled, an epicyclic gear system comprising a sun gear to which the first drive shaft is coupled, a ring gear to which the second drive shaft is coupled, and planetary gears meshing with both the sun gear and the ring gear, an output drive coupled to the planetary gears, and, a one-way rotation restraining means coupled to the second shaft to permit rotation of the second shaft in one direction and to prevent rotation of the second shaft in the other direction for restraining motion of the second shaft during start up of the first motor, and a one-way rotation restraining means coupled to the first drive shaft for restraining rotation of the first shaft during start up of the second motor, and clutch means operable to interconnect said first and second moto

Abstract: An ultra-high speed, axial gap alternator that can provide an output to a plurality of loads, the alternator providing magnetic isolation such that operating conditions in one load will not affect operating conditions of another load. This improved alternator uses a rotor member disposed between a pair of stator members, with magnets disposed in each of the rotor member surfaces facing the stator members. The magnets in one surface of the rotor member, which alternate in polarity, are isolated from the magnets in the other surface of the rotor member by a disk of magnetic material disposed between the two sets of magents. In the preferred embodiment, this disk of magnetic material is laminated between two layers of non-magnetic material that support the magnets, and the magnetic material has a peripheral rim that extends to both surfaces of the rotor member to enhance the structural integrity.

Abstract: An integrated drive generator (40) for generating constant frequency alternating current which is driven by a drive shaft (12) at variable rotational speeds includes a constant speed drive having an input coupled to the drive shaft and at least one output which rotates at a fixed rotational velocity in response to the drive shaft rotating at a variable velocity and which drives a first drive shaft at a fixed rotational velocity and a second drive shaft at a fixed rotational velocity, an alternating current generator (23), having a rotor (37) mounted on a first shaft (42), with an outside periphery having a second radius farthest from an axis of rotation of the first shaft; an exciter (20) having a rotor (32) mounted on the first shaft, electrically coupled to a field winding of the generator, for supplying electrical power to the field winding of the alternating current generator; a permanent magnet generator (18), having a rotor (24) mounted on the second shaft, electrically coupled to the exciter, for suppl

Abstract: The invention relates to an electric motor comprising a rotor (1), a stator (2) and at least two pole pairs. One particularly preferred application of the electric motor according to the invention is small-size accurate servomotors of high capacity. At present the feed back information required by servomotors is generally obtained from at least partially separate transduced means attached to the servomotor, such as an optical or magnetic coder, a tachogenerator or resolver. A drawback of these known solutions is mainly that the volume and weight of the motors is high. This problem is eliminated in the motor according to the invention by providing it with an integral resolver so that primary windings (4a, 4b) of the resolver is arranged in the rotor (1) of the motor, and that secondary windings (11a, 11b) of the resolver are wound round the stator (2) of the motor in such a manner that the winding wire goes alternately inside and outside the stator.

Abstract: A brushless motor of the invention has a plurality of stator members in which arc-shaped magnetic pole portions are arranged around a periphery of a magnet rotor. One of the stator members is constructed such that a plurality of magnetic pole portions are continuously formed. For the number of parts, the number of stator members is smaller than the number of magnetic pole portions.

Abstract: A variable speed controllable induction motor comprises a single rotor formed in one-piece having different sets of rotor conductive members effective respectively at different speed ranges, that is, at least a set of first conductive members specifically effective for a lower speed range and a set of second conductive members specifically effective for a higher speed ranges; a plurality of stators disposed side by side surrounding and facing respective portions of said rotor; and a phase shifting apparatus for producing phase differences on the respective portions of the rotor conductive members. The motor can achieve an overall wide range speed control due to the combined effects of the characteristics obtained respectively from the different set of the rotor conductive members.

Abstract: A motor is equipped with a magnetic structure, stator assemblies having a non-magnetic molding member for being incorporated in the magnetic structure and coils for being wound on the outer periphery of each stator assembly.The magnetic structure is provided with magnetic pole plate bodies, a recess provided in each magnetic pole plate body, bridge members incorporated in the magnetic pole plate body in such a manner as to surround the recess and a plurality of terminal elements whose base ends are coupled to the bridge members and whose free ends are extended toward the recess. The recess, together with the free ends of the terminal elements, is filled with the non-magnetic molding member. On the other hand, the bridge members are not embedded with the non-magnetic molding member but are subsequently cut and removed, so that the base ends of the terminal elements are arranged in such a manner as to project from the surface of the non-magnetic molding member.

Abstract: An assembly comprising an electric motor that is coupled to an operating machine by a belt in which the electric motor is fastened so that its shaft is parallel to the shaft of the operating machine. The motor is supported by a base plate that is mounted on a cantilever so as to be able to tilt horizontally when being adjusted with at least one adjusting bolt to aid in tightening the belt that connects the operating machine and the electric motor. A one piece intermediate part that has two side pieces that enclose an angle is fastened to the cantilever at the free ends of the side pieces. The base plate is fastened to the intermediate piece in the region where the side pieces join. One side piece extends in the direction of the base plate. The longitudinal extension of the other side piece between the joining region and the cantilever is dimensioned so that the strength and yield point of the material allows the required tilting motion of the base plate to occur.

Abstract: Generator rotor for a turbo-generator in which the rotor winding is fed via two feeding conductors, which are each arranged in a bored channel in the rotor body. The two channels diverge in relation to one another and each channel is bored in part in an axial shaft portion of the rotor body and in part in the slotted rotor portion of the rotor body.

Abstract: A motor with an auto output adjusting device. This motor has a plurality of stator independent coils to drive the rotor separately and a torque sensor sensing how large the load of the machine the motor drives is and commanding an electric circuit for adjusting the number of said stator independent coils to get electricity according to the load sensed by said torque sensor. Then this motor can economize the electric power by cutting down the current used in driving the machine when the machine is working idle or below its maximum load.

Abstract: A brushless electrical machine has a stator assembly with spaced coils and a rotor assembly with spaced permanent magnets and with axial air gaps between the assemblies. The magnets define rotatable flux-producing modules and the coils are in positions adjacent to the paths of travel of the magnets. The machine can be operated as a low speed, high torque motor or as a low speed, high power output generator with output characteristics proportional to the number of axially interleaved stator and rotor assemblies.

Abstract: An assembly is provided formed by an electromagnetic vehicle retarder and its electric supply means, where the retarder has a rotor (2) mounted on the output shaft of the gearbox of the vehicle and a stator (13) cantilevered on the casing of this gearbox. The armature (5) of the retarder forms part of the stator and is cooled by water and its inductor (4), which forms part of the rotor, is fed electrically by an alternator whose rotor (13) and stator (14) are secured respectively to the rotor (2) and the stator (3) of the retarder.

Abstract: A generator device has a reluctance generator. The reluctance generator comprises stator coils and an I-shaped rotor. The stator coils includes a winding phase for being supplied with a 90.degree.-leading armature current to generate a no-load induced electromotive force. The I-shaped rotor has an extremely small magnetic reluctance in a first direction normal to a rotational axis thereof and a large magnetic reluctance in a second direction normal to the first direction.

Abstract: The present invention includes an electromagnetic motor having an asymmetric field stator. An aluminum rotor 6 includes a gorup 26 of permanent magnets that occupy a 153.degree. segment of the rotor 6 and are counterbalanced mechanically by brass counterweights 28 on the other side of the rotor 6. An aluminum stator housing 42 includes a large segment 48 of permanent magnets 54 separated by an electromagnet segment 50 from a small segment 52 of permanent magnets 54. The large segment 48 subtends an angle of 122.degree., the small segment 52 an angle of 22.degree.50' and the electromagnets 43.degree.. The permanent magnets 54 and electromagnets 56 and 58 of the staotr 42 produce a magnetic field that can have its center shifted from a first position or equator C by 32.degree.25' to a second position or second equator C'. As the rotor 6 spins the shifting of the center of the magnet field created by the stator 42 imparts momentum to the rotor 6 as it tries to align with the stator magnetic field.

Abstract: A multi-phase stepper motor having an annular permanent magnetic rotor and a plurality of matingly engageable stator phase assemblies around the rotor. Each of the phase assemblies comprises a pair of annular pole pieces including interleaved salient stator poles. The stator pole pieces in each pair are mated together in an opposed relationship to form an annular space between them to receive an energizing winding, and the winding for each pair is of a different phase. Depending upon the number of phase assemblies, the machine can operate in more than two phases. The diameter of the rotor is between about 55 percent and about 75 percent of the motor diameter, and approximately 40 percent more torque is produced than with equivalent sized conventional motors.