Abstract: Three-phase/d-q converters convert an output voltage V outputted from a power converter and a coil current flowing through a propulsion coil to a voltage and a current in a dq rotary coordinate system, respectively. A speed electromotive force observer estimates speed electromotive force based on these voltage and current, and a vehicle angular speed &ohgr;, and a speed electromotive force phase generator calculates a speed electromotive force phase &thgr;e based on the estimated speed electromotive force Zd, Zq. A phase synchronization controller constituted as a secondary PI control system stabilizes the speed electromotive force phase &thgr;e and outputs it as a phase reference &thgr;*. Accordingly, it is possible in a system of an LSM vehicle to obtain the stable phase reference &thgr;* with a minimum deviation even when the vehicle is running at low speed.

Abstract: To prevent adverse effect, on machining accuracy, of cogging thrust of linear motors when used in a combined linear motor driving a machine tool. Three linear motor movers are fixedly attached to a moving table of a machine tool, while three linear motor stators are fixedly attached to a base. The three linear motors are driven in parallel to thereby drive the moving table. The respective linear motor stators are fixed to the base so as to have fixed phases relative to the base, stepwisely displaced by an electrical angle 60° whereby cogging thrust is leveled in the entire combined linear motor.

Abstract: A sheet transport system for a rotary printing press, including a sheet transport device having a sheet holder, and a first and a second propulsive drive element for propulsively driving the sheet transport device guidingly in a first and a second guide rail, respectively, the second guide rail extending substantially parallel to the first guide rail, the first and the second propulsive drive elements forming rotors of an electric linear drive, the first and the second guide rails having a plurality of drive stations disposed thereon and forming a stator of the linear drive, and a control device assigned to the drive stations for controlling and regulating movement of the first and the second propulsive drive elements, each of the first and second propulsive drive elements being a structure formed of magnetizable material, at least part of which is movable relative to another part thereof, and the drive stations being spaced from one another, at least in some sections of the sheet transport device, a distance

Abstract: A circuit arrangement (3) of modular design, in particular for propulsion of a railroad vehicle, having at least two series-connected, power-electronic modules (M1, M2, . . . Mn), which each have a DC isolation point. A first (M1) of these modules is connected to high voltage and a second (M1) is connected to frame or ground potential. The first module (M1) has a first power-electronics assembly (4) which is at high voltage and is connected to a power-electronics assembly (4) (which is at a lower potential) of the second or of a third module (M2). The power-electronics assemblies (4) of each module are arranged in one of several equivalent and dielectric material housings (10), each of which is normally designed in a cuboid shape. The housings (10) are arranged parallel and at a short distance away from one another with regard to their height on a plate (9) which is at frame or ground potential.

Abstract: A digital image printer that performs certain digital image processing functions using parallel integrated circuitry and other functions using serial integrated circuitry in an effort to minimize integrated circuit real estate. The serial integrated circuitry is allocated to certain functions within digital image printing system that perform various mechanical operations. The inherent mechanical time constant of these mechanical operations, when compared to electrical digital image processing operations performed using modern integrated circuitry, is relatively long. In other words, the mechanical operations are performed in a relatively longer time than is made possible using modern integrated circuitry and processors employed within digital image printing systems. The present invention dedicates certain of the functions used to perform digital image processing to be performed using slower, serial integrated circuitry.

Abstract: A system is disclosed for correcting for rotational errors in a linear motor system. A shunt resistor is coupled in parallel with a winding of a phase of a motor of the linear motor system to correct for rotational errors caused by differences in the magnetic characteristics of the motors comprising the linear motor system. Yaw error values for the motors are sequentially measured to determine the value of the shunt resistor, and its location on a winding of a phase motor of the linear motor system.

Abstract: In a linear-motor-driven transport installation, in particular a linear-motor-driven simultaneous stretching installation, the tenter-clip carriage return section (10) is divided into at least three zones, namely a first speed-changing zone (17), a following transporting zone (19) and a subsequent braking zone (21). The length of the speed-changing zone (17) and the braking zone (21) is together less than 40% of the overall length of the return section (10). Only in the speed-changing zone (17) and/or braking zone (21) are more powerful drive devices provided than in the other part of the return section (10), in order to subject the carriages there to a more intense change in speed.

Abstract: An improved control device for linear-motor-driven equipment, in particular for the drive of tenters of a film stretching plant, has a central control device (1) and a multiplicity of converters (11) that are activated thereby, at least indirectly. An improvement is achieved by a phase profile, which describes a relationship between the phase angle, the current amplitude and a clock pulse, for activating the stator winding (7) in a relevant zone (5), being able to be predefined for the converters (11), and by the corresponding phase-profile data for the activation of the stator winding (7) being able to be calculated and/or generated in the converters (11). In addition, a synchronization device, via which the time signals in the converters can be synchronized with one another during operation, is provided.

Abstract: A dual guide beam stage mechanism for accurate X-Y positioning for use e.g. in semiconductor processing equipment provides accurate planar motion and yaw control. Over-constraint between components in their relative motion is minimized by utilizing flexibly mounted air bearings at the connection between at least one of the moveable guide beams and its corresponding stationary guide, and between at least one of the guide beams and the adjacent stage itself. Thus stage yaw motion is provided by allowing yaw motion of one of the guide beams. Preloading provides enough constraint through the air bearings without over-constraining the moving components, thereby improving accuracy and also reducing the need for close manufacturing tolerances.

Abstract: A guideless stage for aligning a wafer in a microlithography system is disclosed, and a reaction frame is disclosed which isolates both external vibrations as well as vibrations caused by reaction forces from an object stage. In the guideless stage an object stage is disclosed for movement in at least two directions and two separate and independently movable followers move and follow the object stage and cooperating linear force actuators are mounted on the object stage and the followers for positioning the object stage in the first and second directions. The reaction frame is mounted on a base structure independent of the base for the object stage so that the object stage is supported in space independent of the reaction frame. At least one follower is disclosed having a pair of arms which are respectively movable in a pair of parallel planes with the center of gravity of the object stage therebetween.

Abstract: A guideless stage for aligning a wafer in a microlithography system is disclosed, and a reaction frame is disclosed which isolates both external vibrations as well as vibrations caused by reaction forces from an object stage. In the guideless stage an object stage is disclosed for movement in at least two directions and two separate and independently movable followers move and follow the object stage and cooperating linear force actuators are mounted on the object stage and the followers for positioning the object stage in the first and second directions. The reaction frame is mounted on a base structure independent of the base for the object stage so that the object stage is supported in space independent of the reaction frame. At least one follower is disclosed having a pair of arms which are respectively movable in a pair of parallel planes with the center of gravity of the object stage therebetween.

Abstract: The electrically operated dispensing appliance comprises two electric motors (1, 26), one of the electric motors (1) acting upon the driving screw (70) through a first gear drive (2) having a greater reduction ratio in order to rotate the driving screw in the advancing direction, and the other one of the electric motors (26) acting upon the driving screw (70) through a second gear drive (27) having a smaller reduction ratio in the other direction in order to retract the driving screw for relieving a dispensing cartridge and in order to turn the driving screw back when the thrust rod(s) (15) are retracted in order to exchange the storage cylinders.

Abstract: The invention relates to an electromotive actuator with a housing for a central door locking system of a motor vehicle having a first slide adjustable by a first electric motor between two end positions. The first slide can be connected with a door lock of the motor vehicle independently of the end position and is preferably decoupled from the electric motor in the end positions, so that the first slide is manually adjustable between its end positions. Such an electromotive actuator is provided with a theft protection capability in the sense that, after a windshield of a motor vehicle is smashed in, an unlocking of the door by the inside locking handle is no more possible because the parts of the actuator are not actuated by operating the inside locking handle. Finally, an unlocking operation initiated from the outside is possible when the theft protection is put into operation.

Abstract: A polar motion bond head for bonding semiconductor devices includes voice coil motors for providing positioning motion to the bond head, and a vision system that has an optical path that allows the camera to see all polar positions with the image staying on the camera centerline.

Abstract: A positioning device includes a table (5, 69), which is displaceable in two coordinate directions (X, Y) by means of Lorentz forces of electric linear motors over a base (3) and is guided over the base (3) by means of a static gas bearing, which has an air gap thickness independent of the coil systems and magnet systems (15-21, 37-43) in the motors. The positioning device is particularly suitable for the manufacture of masks with patterns for integrated circuits.

Abstract: An apparatus for multi-axis rotational motion includes a spherical structure (102) and a housing (104), the housing (104) at least partially enclosing the spherical structure (102) and movably coupled thereto. Magnetically compliant poles (106, 107, 108, 109) are mechanically coupled to one of the spherical structure (102) and the housing (104), and a magnetic drive mechanism (114) is mechanicanically coupled to the other one of the spherical structure (102) and the housing (104) for magnetically imparting up to substantially 360 degrees of rotational motion between the spherical structure (102) and the housing (104) in multiple axes by magnetically interacting with the magnetically compliant poles (106, 107, 108, 109). Optionally, at least one of the spherical structure (102) and the housing (104) couples the rotational motion to another object (1906) mechanically coupled thereto via surface coupling.

Abstract: In order to obtain a manipulator using a plane pulse motor showing advantageous features such that even in a case where a moment of force is applied to the manipulator in a falling direction, the moment can be sustained by magnetic attraction caused by the pulse motor, the weight of the manipulator is reduced, the degree of freedom of the movement can be increased, and a rotating mechanism for a tool itself is eliminated; a plurality of movable members are provided on a stator of the plane pulse motor, a rotatable shaft is provided on each movable member so as to extend vertically, the rotatable shafts are connected with each other through a connecting member, a required tool is secured to the connecting member, and the movements of the movable members are made controllable in a manner correlated with each other. The manipulator using the plane pulse motor of the aforementioned construction is most adapted to be used in combination with an industrial robot and the like.

Abstract: A transporting system includes plural primary dispersedly arranged linear induction motors and plural continuously movable bodies connected by a secondary conductor in an endless path. At least one of the linear induction motors is directly controlled by an inverter control device, and the remaining linear induction motors are switchably connected to a power source. A running speed of the moveable bodies is detected, and the difference between the detected running speed and a desired running speed is used to control the inverter control device and the switching of the remaining induction motors to the power source. A voltage controller can be used in place of the inverter control device.

Abstract: A power supply system for a linear motor type transportation system includes a series of driving coils disposed along a railroad track for producing a moving magnetic field to drive a train, a plurality of feeding blocks disposed along the railroad track for supplying electric power to the series of driving coils, a plurality of power converters each connected to the corresponding feeding blocks to supply electric power to each corresponding feeding section composed of the feeding blocks, and a plurality of block switches connected between neighboring two feeding blocks of the feeding blocks.

Abstract: The invention concerns a phase locked loop speed control circuit for controlling the speeds of two or more objects. It includes pulse generators for generating reference pulses, first counters for counting each of these reference pulses, encoders for detecting relative travelling distances of the objects, second counters for counting encoder pulses from the encoders, first subtracters for subtracting the outputs of the second counters from those of the first counters, second subtractors for subtracting the encoder pulses from the reference pulses, corrector sections for correcting the differences output by the first and the second subtractors, and adjusting sections for adjusting the movements of the objects based on the corrected differences.

Abstract: A linear guide apparatus comprises a fixed body; a movable body movable on the fixed body in a predetermined direction; a retainer disposed between the fixed and movable bodies, for rotatably supporting rolling bodies brought into contact with the fixed and movable bodies; a first rack provided on the fixed body in the predetermined direction; a second rack provided on the movable body in the predetermined direction; a third rack provided on the retainer in the predetermined direction; a first pinion in mesh with the first and third racks, respectively; and a second pinion in mesh with the second rack. The first and second pinions are coupled integrally and coaxially with respect to each other and disposed rotatably and slidably in the predetermined direction. Further, a pitch diameter of the second pinion is three times larger than that of the first pinion.

Abstract: Methods for rapidly determining the discrete control information to independently propel a plurality of carriages with a synchronous linear motor divided into zones for control are useful for a steady state or a transition operation for a linear motor control system.

Abstract: The invention relates to a linear motor feeder system in which a linear motor is supplied with driving power from equipment on the ground. Divided armature coils are serially connected two by two to form sets of the armature coils, the junction between the two armature coils in each set is connected to one feeder and both ends of the set of armature coils are connected to two feeders via respective switches, and short-circuiting switches are connected between mutually adjacent ones of the feeders. By turning these switches ON and OFF in accordance with the position of a vehicle, the linear motor is driven by a single frequency converter connected across feeders which are in turn connected across both ends of the divided armature coils.

Abstract: The assembly (10) is a self-propelled conveyor system including a vehicle (12) having wheels (18) and a motor (16) for moving the vehicle (12) along a track (20). The vehicle (12) includes a speed sensor (24) for sensing actual speed of the vehicle (12) and a location sensor (26) for sensing the absolute position of the vehicle (12) along the track (20). A control (22) receives the actual speed and absolute location signals and drives the vehicle (12) at a speed associated with the absolute position, this value being obtained from a memory (32). The control (22) drives the motor (16) at the selected speed with a feedback signal of actual speed wherein the control (22) may adjust the drive signal when actual speed differs from selected speed.

Abstract: A system useful for controlling multiple secondaries of a linear disposed motor along an elongated path, with the system having a linear synchronous motor with its elongated primary disposed along the elongated path and at least one secondary responsive to the primary with means disposed thereon for attachment to a body to be propelled along the path, a plurality of linear synchronous motor drivers for providing inputs to designated coil windings of the primary for developing a traveling electromagnetic wave along the primary, a driver controller means connected to each motor driver which has plurality of memory sections for storing therein characteristics of waveforms for use in the system of the invention, a central controller for controlling the output of the plurality of driver controller means and a system computer for down loading instructions for the various waveform patterns to the memories of the driver controller means and for overall supervisory control of the system of the invention.

Abstract: A positioning table includes a pair of parallel rails defining an axis of motion. A movable assembly including a first linear motor assembly disposed for motion along one of the rails. An outboard linear motor assembly on the other rail is rigidly bridged to the first linear motor assembly for concerted motion therewith. The first linear motor assembly includes a plurality of permanent magnets defining a plane at a predetermined angle to the horizontal and an armature defining a plane at the same angle closely spaced from the permanent magnets. The permanent magnets may be disposed on the movable element of the linear motor assembly or on the first rail. The armature is disposed on the other of the movable element and the first rail. First and second bearings on the movable element of the linear motor assembly, which may be air bearings support loads in the vertical and horizontal directions.

Abstract: An electromagnetic launcher includes a plurality of electrical stages which are energized sequentially in synchrony with the passage of a projectile. Each stage of the launcher includes two or more coils which are arranged coaxially on either closed-loop or straight lines to form gaps between their ends. The projectile has an electrically conductive gap-portion that passes through all the gaps of all the stages in a direction transverse to the axes of the coils. The coils receive an electric current, store magnetic energy, and convert a significant portion of the stored magnetic energy into kinetic energy of the projectile by magnetic reconnection as the gap portion of the projectile moves through the gap. The magnetic polarity of the opposing coils is in the same direction, e.g. N-S-N-S.

Abstract: A bi-directional drive motor of the type having a force coil suspended in a magnetic field of a magnetic core assembly is provided. The force coil is made larger than the center pole piece which it surrounds so that the force coil is movable transverse to the length of the center pole piece as well as along its length to provide both X and Y directional movement. When two force coils are connected together on orthogonal axes and mounted in a common magnetic core assembly, X and Y directional movement is provided in a single drive motor system. When two drive motor systems are coupled to the same side of a top stage of a load platform, rotational or theta positioning is provided in addition to X and Y positional movement.

Abstract: A linear motor-driven table apparatus capable of operating both in fine-feed mode and large-feed mode has a base, an intermediate carriage received in a longitudinal recess in the base and supported movably by linear bearings fitting on both opposing walls of the recess, and a table body received in a longitudinal recess in the intermediate carriage and movably supported through linear bearings fitting on both opposing walls of the recess. The movement of the intermediate carriage with respect to the base is effected by a first linear motor acting therebetween, while the movement of the table body with respect to the intermediate carriage is effected by a second linear motor acting therebetween. The amount of feed is controlled by controlling the supply of pulses to these linear motors.

Abstract: A dual motor linear actuator is disclosed for use in a magnetic disc drive device. It includes a carriage reciprocatably guided between a pair of guide rails, with the accessing transducers being mounted to its inner end. Separate rectangular drive coils are affixed in symmetrical outboard relationship at the sides of the body of the carriage. The actuator assembly further includes two pairs of slab shaped magnets mounted to E-shaped magnet support structures that are integrally formed with the base of the disc drive device. The magnets are mounted to form two air gaps that are symmetrically disposed relative to a center plane and so that they respectively cooperate with the drive coils to apply motive forces on the carriage generally along two lines that are equidistantly spaced from the aforesaid plane of symmetry. The outer ends of pole pieces of the two magnet support structures are rigidly interconnected by a single plate that acts as an end pole piece for both magnet support structures.

Abstract: A magnet controller for a magnetically suspended vehicle of the linear stator type for travelling along a rail track (1) forming a linear stator having teeth of uniform determined width, responds to a rectified control signal. The control parameters for the magnet controller (21) are adjusted in response to speed to assure a stable control during standstill and at low speeds and to achieve a good response or follower characteristic of the control system at high speeds. A speed representing signal (U.sub.v) is generated in a conductor loop, preferably a double loop (9), inserted into a groove (10) of the poles (5) of the levitation magnets (2). The signal (U.sub.v) generated in the conductor loop is rectified at (31), and if desired passed through a low-pass filter (32) to provide the control input signal for the controller (21) by a very simple circuit. Utilizing just the amplitude of the speed signal (U.sub.

Abstract: A transport control system with linear motor drive applicable for cash transport in a bank. The system uses a main controller, a rail-path, a carrier adapted to be driven along the rail-path by linear motor drive, and a plurality of stator portions coupled to the rail-path to produce a driving force in association with the carrier. Each of the stator portions includes a stator controller for controlling the driving of the carrier. The stator controller controls the driving of the carrier passing the stator portion to which the stator controller belongs to cause the carrier to reach a destination stator portion.

Abstract: Disclosed is a power supply apparatus for a linear motor transportation system having a number of discrete linear motor units serially arranged along a track to generate a moving magnetic field for driving vehicle.

Abstract: A conveying apparatus of the type including a plurality of driving means disposed in the spaced relation along a track so as to allow a carriage to move on the track under the influence of inertia with the aid of propulsive force or reverse propulsive force which is generated by the plural driving means. The track has at least a curve and another driving means is disposed at the position upstream of the curve as seen in the direction of transportation of the carriage. To assure that the carriage moves along the curve at a proper moving speed a desired speed is so determined that centrifugal force exerted on the carriage is maintained at a level equal to or lower than a predetermined value. Speed controlling is effected in such a manner that the carriage is decelerated or accelerated from the moving speed detected at the time before it enters the curve to the desired speed by means of the last-mentioned driving means.

Abstract: A robotic system includes two joints moving a common load-bearing member along a path for positioning a load. Each joint includes a linear electric motor and a feedback loop, the latter driving the motor accurately in response to a commanded position signal, and a true position signal provided by sensor apparatus disposed alongside a track of each linear motor. Cross-coupling circuitry connects with the sensor apparatus of each joint to produce signals representing differences in positional error and in speed of the joints. The signals are injected into the feedback loops of the joints to effect a shift of power between the joints to synchronize their travel. Window comparator circuitry is employed for introduction of variable gains to the feedback loops for values of positional error and velocity which are greater than reference values in a window.

Abstract: A surface pulse motor having a stator and a mover is provided such that the stator is made of a magnetic material of a planar configuration with a number of projections formed on a surface thereof at positions corresponding to the intersecting points of a first lattice. The mover is made of electromagnets of predetermined phases, each electromagnet having a number of projections formed on a surface thereof opposing the surface of the stator at a pitch equal to that of the first lattice. When a second lattice which is rotated relative to the first lattice by a predetermined angle is assumed, the electromagnets other than the first phase are displaced from that of the first phase by a distance corresponding to a fraction of the pitch of the first lattice in directions of the coordinate axes of the second lattice, respectively.

Abstract: A system useful for controlling multiple secondaries of a linear disposed motor along an elongated path, with the system having a linear synchronous motor with its elongated primary disposed along the elongated path and at least one secondary responsive to the primary with means disposed thereon for attachment to a body to be propelled along the path, a plurality of linear synchronous motor drivers for providing inputs to designated coil windings of the primary for developing a traveling electromagnetic wave along the primary, a driver controller means connected to each motor driver which has plurality of memory sections for storing therein characteristics of waveforms for use in the system of the invention, a central controller for controlling the output of the plurality of driver controller means and a system computer for down loading instructions for the various waveform patterns to the memories of the driver controller means and for overall supervisory control of the system of the invention.

Abstract: A first table is provided on a fixed base so that the first table can be moved in one of two directions which cross each other at right angles. A second table is provided on the first table so that the second table can be moved in the other direction. Linear motors for applying the driving force to the first and second tables to directly drive these tables are provided between the fixed base and first table and between the first and second tables.

Abstract: A plurality of spaced drive means are disposed along a conveyance path for running a carriage along the conveyance path by a forward or reverse propelling force created by the drive means. A main power source and an auxiliary power source are provided for switching a power source from the main power source to the auxiliary power source when the former becomes faulty for running and stopping the carriage at a selected one of the drive means for the purposes of preventing the carriage from stopping at an intermediate point between adjacent drive means.

Abstract: A two axis linear motor for carrying the objective lens for optical focusing and optical tracking in an optical recording system has a stationary structure for providing a magnetic field and a moving armature structure. The stationary structure may have two permanent magnets and several pole pieces to properly shape the field with respect to the armature. In one embodiment, a central elongated pole piece and two parallel adjacent elongated pole pieces which are associated with two permanent magnets to form flux gaps with the central pole piece. Flux returns to the magnets through a lower pole piece to which the central pole piece is attached. The central and lower pole pieces have an aperture through which the laser beam may pass on its way to and from the objective lens.

Abstract: This invention is directed to electromagnetic alignment apparatus, which is particularly adapted, among other possible uses, for use in aligning the wafers in a microlithography system, said apparatus comprising in combination a first magnetic circuit having a plurality of elements including a first magnet; a second magnetic circuit having a plurality of elements including a second magnet; the second magnetic circuit being disposed in spaced relationship with respect to the first magnetic circuit; a movable structural component adapted for mounting an object thereon; one element of each magnetic circuit being fixedly attached to the movable structural component; first and second current carrying coil assemblies mounted in the first magnetic circuit; the second coil assembly being disposed at an angle with respect to the first coil assembly; third and fourth current carrying coil assemblies mounted in the second magnetic circuit; the fourth coil assembly being disposed at an angle with respect to the third coi

Abstract: A two-axis positioning system comprising three linear motors, two of which are spaced at a predetermined interval and disposed movably in the direction of a first axis and another one of which is supported by two motors and made movable in the direction of a second axis, the three motors having position control loops independent of or related with each other corresponding to input movement command signals in the directions of the first and second axes.

Abstract: This invention is directed to electromagnetic alignment apparatus, which is particularly adapted, among many other possible uses, for use in aligning the wafers in a microlithography system, said apparatus comprising in combination three or more spaced magnets, three or more coil assemblies mounted to pass through the magnetic fields of the magnets respectively, means for controlling the flow of current through the coil assemblies respectively, said coil assemblies being joined together to form a structure movable with respect to the magnets and adapted to carry an object thereon, the coil assemblies being wound with respect to each other so that by controlling the supply of current to the coils the structure can be moved selectively in three degrees of freedom.

Abstract: This invention is directed to electro-magnetic alignment apparatus, which is particularly adapted, among many other possible uses, for use in aligning the wafers in a microlithography system, said apparatus including in combination at least three magnet assemblies which are mounted in space relationship one with respect to the others, at least three coil assemblies mounted to pass through the high flux region of the magnet assemblies respectively, the width of the coil assemblies being substantially less than the width of the high flux regions respectively, a controller for controlling the flow of current through the coil assemblies respectively, a structural assembly for connecting the coil assemblies which is movable with respect to the magnet assemblies, the coil assemblies being wound with respect to each other so that by controlling the supply of current to the coils the structure assembly can be moved selectively in three degrees of freedom.

Abstract: Movable (a head) and stationary (a stator) members are disposed in contiguous relationship. First magnetizable and non-magnetizable zones are alternately disposed on the stator in a particular direction. Second magnetizable and non-magnetizable zones are alternately disposed on the head in the particular direction. The zones on the head and the stator face each other and have substantially equal spacings. First means are associated with the head for producing magnetic fluxes in the magnetizable zones in the head and stator in a particular pattern to obtain incremental relative movements between the head and the stator on a vectorial basis in the particular direction. Second means are associated with the head for compensating for hysteresis effects in the magnetizable zones in the head and stator. The second means may produce magnetic flux of alternating polarity and decaying amplitude near the end of each incremental movement of the head relative to the stator.

Abstract: An electric drive includes two d.c. electric motors electrically connected therebetween, each of them comprising a stationary former of magnetic field, a movable portion 1,2, an excitation winding 3,4, and an armature winding 5. A commutating device 25 is connected to the armature winding 5. The former of magnetic field is a ferromagnetic strip 22 or 23 provided with pole-forming projections disposed in two rows in the chessboard order. The armature winding 5 is common for both the motors, its sections being uniformly distributed among the motors, and the ends of the sections are led out at the side of one of the motors and connected to the commutating device 25 for forced commutation of the sections in a function of a relative location of the ferromagnetic modules of the movable portions and pole-forming projections.

Abstract: A dual motor linear actuator is disclosed for use in a magnetic disc drive device. It includes a carriage reciprocatably guided between a pair of guide rails, with the accessing transducers being mounted to its inner end. Separate rectangular drive coils are affixed in symmetrical outboard relationship at the sides of the body of the carriage. The actuator assembly further includes two pairs of slab shaped magnets mounted to E-shaped magnet support structures that are integrally formed with the base of the disc drive device. The magnets are mounted to form two air gaps that are symmetrically disposed relative to a center plane and so that they respectively cooperate with the drive coils to apply motive forces on the carriage generally along two lines that are equidistantly spaced from the aforesaid plane of symmetry. The outer ends of pole pieces of the two magnet support structures are rigidly interconnected by a single plate that acts as an end pole piece for both magnet support structures.

Abstract: An arrangement for distributing electrical power to one or more portions of a linear motor stator, the stator being of the type which is disposed along a track for propelling a track-bound vehicle. Current is supplied to the stator from a line conductor which is supplied at both ends by respective power supplies. In a further embodiment which is useful for distributing electrical power to long stators, double-throw switching elements are connected to the power supplies for permitting the power supply to provide current to a selectable one of two adjoining line conductors.

Abstract: An electromagnetically actuated, linear reciprocating self-timed motor employs plural reciprocating electromagnet pistons which oscillate between opposed fixed electromagnets having primary and secondary coils. The fixed electromagnets are alternately energized to effect large repulsion forces between the fixed electromagnets and the reciprocating electromagnet pistons. Secondary coils carried by the fixed electromagnets cause electrical energy induced therein during reciprocation of the pistons to be fed back to the d.c. source supplying energy to the primary coils of the fixed electromagnets. A crankshaft driven rotor bearing permanent magnets develop signals within stationary pick-up coils for controlling switches for timed energization of the primary coils of the fixed electromagnets.

Abstract: A dual motor linear actuator is disclosed for use in a magnetic disc drive device. It includes a carriage reciprocatably guided between a pair of guide rails, with the accessing transducers being mounted to its inner end. Separate rectangular drive coils are affixed in symmetrical outboard relationship at the sides of the body of the carriage. The actuator assembly further includes two pairs of slab shaped magnets mounted to E-shaped magnet support structures that are integrally formed with the base of the disc drive device. The magnets are mounted to form two air gaps that are symmetrically disposed relative to a center plane and so that they respectively cooperate with the drive coils to apply motive forces on the carriage generally along two lines that are equidistantly spaced from the aforesaid plane of symmetry. The outer ends of pole pieces of the two magnet support structures are rigidly interconnected by a single plate that acts as an end pole piece for both magnet support structures.