Abstract: A propulsion system for an aircraft, which has a chassis, a propeller able to move in rotation about an axis of rotation, a main gear as one with the propeller, an electric generator, at least one linear electric motor having a fixed element and a slider able to move in translation, for each linear electric motor, a secondary gear meshing with the main gear and mounted to be able to move in rotation about an axis of rotation perpendicular to the axis of rotation, and a rod of which one end is articulated on the corresponding slider and of which the other end is articulated on the corresponding secondary gear at an articulation that is offset with respect to the axis of rotation of the secondary gear.

Abstract: A motor of this invention comprises a rotor having a permanent magnet, the number of which magnet poles is P, and a stator including M pcs of teeth, the teeth arranged in a circumferential direction in a manner to face the permanent magnet through a spatial gap, wherein the stator includes stator core having the number M of the teeth, and a winding wire wound about each of the tooth, wherein the number P of the magnet poles and the number M of the teeth have a relation defined by formulae (2/3)M<P<(4/3)M, and M?P, and wherein ratio (t1/Ds) of teeth tip width t1 to stator inside diameter Ds is given by a formula 0.18<(t1/Ds)<0.25.

Abstract: In one embodiment, a latching sector motor actuator includes a housing, a permanent magnet, and a pole piece. The permanent magnet rotates relative to the housing. The pole piece has a polarity and a pair of wound wire coils, is fixedly attached to the housing, and communicates with the permanent magnet to cause the permanent magnet to rotate one of clockwise and counterclockwise, depending upon the polarity of the pole piece. In another embodiment, a failsafe sector motor actuator has a pole piece with a singularly wound wire coil and further includes an auxiliary permanent magnet. The auxiliary permanent magnet is adjustably attached to the housing to extend rotation of the permanent magnet from 80° to 120°, depending upon location and magnitude of the auxiliary permanent magnet.

Abstract: An oscillating design display is described. Such a design may include virtually any personalized design a customer may desire. By generation of a magnetic field from an induction coil, such a displayed design may be made to oscillate between two endpoints in a single plane of motion. Such an induction coil may be powered by solar energy.

Abstract: A flywheel levitation apparatus and associated method are described for use in a flywheel driven power storage system having a rotor and which provides for an upward vertical movement of the rotor along an axis of rotation. The rotor includes a rotor face defining a cutaway section. A magnetic lifting force is applied to the rotor to at least in part serve in levitating the rotor. The magnetic lifting force exhibits a modified gap sensitivity that is smaller as compared to a conventional gap sensitivity that would be exhibited in an absence of the cutaway section.

Abstract: A three-stable oscillating electromagnetic actuator includes a cylindrical stator from which a plurality of first magnetic poles project toward a center direction, a mover that extends in a circumferential direction inside the stator and is reciprocatingly and rotatably supported along the circumference, and a plurality of coils that are wound around the first magnetic poles and bias the mover to cause it to stop in three positions, which are a first stable position that is on one end side of a rotation range of the mover, a second stable position that is on the other end side, and a neutral position that is an intermediate position. The three-stable oscillating electromagnetic actuator further includes a second magnetic pole made of a magnetic material that abuts against a rotation-direction end of the mover to stop the mover in the first stable position and the second stable position.

Abstract: The actuator system has a external rotor motor having: (i) an internal armature configured as a stator having a set of coils wrapped around a set of arms, and (ii) an external permanent magnet rotor having a set of poles configured to rotate less than 90 degrees around the stator. The actuator system has a drive shaft configured to be rotated by the external rotor motor. The actuator system has a drive train connecting the external permanent magnet rotor to the drive shaft, and configured to provide gear ratio to the drive shaft.

Abstract: The present invention provides a linear motor device that can reduce a variation in thrust caused by a variation in attractive force. The linear motor device includes a linear motor 1 and a control section 30 that controls the linear motor 1. The linear motor 1 includes a magnet member 2 composed of permanent magnets having respective N poles and S poles alternately arranged in an axial direction, and a coil member 3 which is located orthogonally to the axial direction with respect to the magnet member 2 and through which the magnet member 2 is movable in the axial direction relative to the coil member 3. The control section 30 controls current conducted through the coil member 3 so that a moving one of the magnet member 2 and the coil member 3 reciprocates within a use range L corresponding to a part of a pitch p between the magnetic poles N and S in the magnet member 2.

Abstract: In a linear motor (1), the detent force is reduced by the height of the iron poles (522) being selected differently in the two outer regions of the coil set, preferably by a gradual reduction of the height of the iron poles (522) towards the ends of the stator (2). In combination with a slight inclination of the magnets, the detent forces are further minimized, with negligible losses of the propulsive force. The exact dimensioning of the iron poles (522) is dependent inter alia on the dimensioning of the coils (51) and other characteristics of the linear motor (1) as a whole, and can be found and optimized by simulations. Here, an optimum is sought between as great a reduction as possible of the detent force amplitude and as high a propulsive force as possible.

Abstract: An electric drive unit for generating an oscillating movement, having a stator, a rotor, a torsion element and a tuning element. The tuning element acts upon the torsion element and serves to mechanically tune the resonant frequency of the drive unit.

Abstract: An electric motor for a small-scale electrical appliance, such as a toothbrush or shaver. The electric motor includes at least one oscillatory motor component, a magnet arrangement having at least one permanent magnet, and a coil for generating a magnetic field which, in interaction with the magnet arrangement, generates a force for excitation of an oscillatory linear motion. During the interaction between the magnet arrangement and the magnetic field produced by the coil, a torque for excitation of an oscillatory rotational motion is additionally generated.

Abstract: A driving assembly of camera shutter and diaphragm comprises a first stator, a second stator, a coil set and a rotor. The coil set is installed between the first stator and second stator. A first wing is axially extended from a round periphery of the first stator and a second wing is axially extended from a round periphery of the second stator. Each of the first stator and second wing is a round cambered sheet. In assembly the first stator and second wing are formed as a space for receiving the rotor; thus the rotor is driven to rotate by the magnetic force of the first wing and second wing so as to drive the diaphragm and shutter. Each of the first wing and second wing has a plurality of parts which are formed around the respective stator and are spaced with an equal spaced.

Abstract: A two-position rotary actuator provides a latching or holding torque which can be adjusted by altering the magnetic properties of a selected pole member. The actuator also functions as a sector motor over a selected range of angular motion and provides failsafe operation which returns the actuator to a starting position when electrical power is removed.

Abstract: A stator is adjustably attached to the frame of a crossed-flexure pivot galvanometer. The stator acts on a permanent-magnetic rotor, having radially facing poles, causing the rotor to torsionally oscillate, which causes the rotor to be displaced from an axis of rotation along a line of displacement. The resonant frequency of the galvanometer is controlled by adjusting the centering of the stator along a line between the radially facing poles of the permanent-magnetic rotor. With this adjustment, as the stator is brought closer to the magnet along the line between the radially facing poles, the frequency-lowering effect is maximized. As the stator is move away from the magnet along the line of displacement, the frequency-lowering effect is minimized.

Abstract: A switched reluctance motor is provided with a rotor position detecting apparatus for detecting a rotor position wherein the apparatus comprises a rotor position-sensing mechanism removably mounted in a ventilator hole formed in a side wall of a motor housing for enabling an easy replacement of printed circuit boards and photo-interrupters when they need to be repaired and maintained. The sensing mechanism includes a fixing member having spaced slots for receiving respective circuit boards.

Abstract: Disclosed is an AC electric motor with oscillating rotary output, a permanent magnet rotor having radially magnetized magnets, and feedback control of oscillation amplitude. Amplitude control is accomplished without a separate amplitude sensor by using an accurate model of the motor as a basis for calculation of amplitude from measurements of motor voltage and current. The motor has high efficiency, low inertia, and uses a relatively small volume of permanent magnet per unit power output.

Abstract: An oscillatory drive incorporating the invention includes a driven rotor that is mounted on a shaft and includes plural driven permanent magnets disposed thereon. A spring arrangement is coupled to the driven rotor and limits both clock-wise (CW) and counter-clockwise (CCW) rotation thereof. A first driving rotor includes first driving magnets, is mounted for rotation on the shaft and is positioned to a first side of the driven rotor. A second driving rotor includes second driving permanent magnets, is mounted for rotation on the shaft and is positioned to a second side of the driven rotor. The drive mechanism imparts a CW rotation to the first driving rotor and a CCW rotation to the second driving rotor. The first driving permanent magnets coupling to the driven permanent magnets causes a CW rotation of the driven rotor until the spring arrangement terminates the CW rotation and causes a reversal of rotation direction in the CCW direction.

Abstract: An electromagnetic motor of the finite rotational type has an improved rotor-returning mechanism for exerting a magnetic force to return its rotor to the initial angular position in a non-excited condition. The rotor-returning mechanism is comprised of a permanent magnet fixedly mounted on a stator and a permanent magnet mounted around the rotor. The permanent magnets are arranged such that, a magnetic attractive force generated between the permanent magnets functions to return the rotor to the initial angular position. The rotor-returning mechanism can be constitued by first and second ring-shaped permanent magnets mounted on the rotor. The N and S poles of the first magnet are offset in a the circumferential direction from those of the second magnet so as to generate a magnetic torque for returning the rotor to the initial angular position.

Abstract: A rotary actuator disk drive in which the rotary actuator is driven by a motor comprising a movable coil and a stationary permanent magnet structure producing a magnetic field which links the coil. The rotary actuator comprises a load beam arm stack and a voice coil arm of electrical insulating material such as a light weight plastic, all of which are axially stacked and swaged to a rotary actuator bearing hub which is rotatably mounted in the disk drive. The coil arm of electrical insulating material has a bobbin section on which the coil is directly wound. The coil arm is molded together with the coil arm mounting bushing, a latch pin of magnetic material and an actuator arm balance weight insert molded therein. The latch pin is linked by the permanent magnet field of the motor permanent magnet structure and functions with that structure to define mechanical limits of angular actuator movement and to magnetically latch the actuator in one angular limit when the disk drive is not in use.

Abstract: Disclosed herein is a swing-arm type linear d.c. brushless motor, wherein at least one coreless type armature coil such as an air-core armature coil is arranged on the inner wall of a linear motor body and a field magnet is formed by magnetizing a magnet member with a single pair of N/S poles so as to permit the generation of thrust in a predetermined direction face to face with only one active conductor of said at least one armature coil and which does not contribute to the generation of reverse thrust. The field magnet is opposite through an air-gap in the axial direction to only the active conductor portion, and is supported relatively and swingably through the air-gap. It is suitable for use in small, economical and high-speed magnetic head positioner mechanisms more useful in small-capacity magnetic disk units and the like and capable of performing position detecting, feed control, etc.

Abstract: This electrical resolver has an arcuate stator with a concave inner side concentric to a convex side of an angularly rotatable arcuate rotor limited to rotation within outer ends of the stator. The stator and rotor have arcuate magnetic cores with transverse slots in which are embedded windings made of insulated wire. Rotation of the rotor causes changes in voltages induced in the stator windings corresponding to the extent of angular position of the rotor. The stator windings include trimming coils which generate bucking voltages to reduce errors in determining angular position of the rotor. In an operating range of .+-.10.degree. from a centered position, magnitudes of rotor position can be determined with an accuracy of 5-10 arc seconds maximum, with a considerable savings in space, weight, cost, simplified installation, and increased stability over the operating temperature range.

Abstract: An electrically driven appliance such as a citrus press comprises a drivable tool; a self-starting single-phase synchronous motor including a diametrically magnetized permanent-magnet rotor forming a rotor field and positioned between two stator poles forming a stator field; and a drive mechanism arranged between the motor and the tool, for driving the latter, such mechanism including a plurality of drive elements each engaging the adjacent element or elements. A stalling device coacts with one drive element having a pair of stops, the stalling device including a member alternately engageable with such stops after a specific number of revolutions of the rotor in either direction of rotation, such engagement effecting stalling of the rotor and automatic reversal of the direction of the rotation of the rotor.

Abstract: An electric motor having an output shaft that rotatably oscillates automatically, the motor comprising a pair of reversing terminals, a reversing switching mechanism for connecting the first reversing terminal to a plus terminal connected to a source of electric power while disconnecting the second reversing terminal from the plus terminal and for connecting the second reversing terminal to the plus terminal while disconnecting the first reversing terminal from the plus terminal, a cam on the output shaft for actuating the reversing switch, and for co-operating with a pair of abutments on the switch limiting the rotation of the output shaft in one direction and in the other, and a spring bias detent for maintaining one of the reversing terminals in connection with the plus terminal until disengaged by the cam.

Abstract: This invention relates to an electrically operated actuator for quarter-turn valves, such as butterfly or ball valves.The actuator includes a single phase 2-pole dynamo-electric machine comprising a stator having three windings and a rotor having a plurality of short-circuited windings. The rotor is coupled directly with the output shaft and the windings of the stator are energised from a power supply through respective limit switches which are cam controlled by the output shaft.One of the stator windings controls the final movement of the actuator in each direction of travel and the limit switch for this winding is broken to de-energize the winding by an adjustable stop mechanism.

Abstract: A simulated clock apparatus utilizes a housing having an opening therein and a shelf disposed in the housing below the opening. A conventional wristwatch is adapted to be rested on the shelf so as to have the face of the clock exposed for external viewing through the opening. A pendulum is pivotably secured to the shelf and is displayed visibly through a second opening located below the opening. The pendulum may be continuously oscillated back and forth in conventional "Grandfather Clock" fashion by a bar passing through a solenoid coil, such that the bar is urged into oscillatory motion, when contacting an electrical switch at an end thereof such that the switch is operated into a closed position causing a current flow from the battery, housed within the housing, to exert a pulling force on a ferromagnetic portion of the center of the bar.

Abstract: A magnetically activated oscillatory motor comprises a pendulum pivotally mounted on mounting means, a pendulum magnet mounted on the pendulum with its poles aligned in the direction of pendulum movement, and first and second electromagnets mounted on the mounting means with their poles aligned to face like poles of the pendulum magnet. An electric circuit includes electric power means and electric switch means, which are associated with the first and second electromagnets to control the flow of current thereto. The electric switch means are mounted on the mounting means in a manner to be engaged by the pendulum when it is near the extremities of its swing to pass current to those electromagnets then adjacent the pendulum repelling the like polarity pole of the pendulum magnet. Thus the pendulum is driven downwardly alternately from the opposite ends of its swing to maintain pendulum oscillation. Drive means is connected to the pendulum to transmit its oscillatory motion to a driven member.

Abstract: Herein disclosed is an electromagnetic rotary motion device including permanent magnets establishing a pair of spaced concentric and coextensive circular or semicircular air gaps and a rotor unit including armatures which are movable in a circular path in and along the spaced air gaps in response to an electric control signal impressed thereon. A typical application of the rotary motion device is a diaphragm-assisted exposure control arrangement of an optical instrument, such as for example, a still camera, a cinema motion camera or a television camera, wherein the diaphragm is driven by the rotor unit for providing a degree of exposure which is optimum for the brightness of an object to be photographed or televised.

Abstract: A rotary actuator provides rotation of its rotor over predetermined angles. The rotor is a cylindrical housing in which are cylindrically curved permanently magnetized poles spaced apart at their ends and surrounding a fixed armature. The armature has magnetic arms angularly disposed with respect to each other which define fixed poles. Coils wound on the fixed poles generate magnetic fields when energized to drive the rotor. A holding coil may be provided to hold the rotor stationary when the holding coil is energized. The armature may have two, three or more fixed poles. The actuator can be operated in rotor latching or fail-safe return modes. Fixed stop members may be used to limit angular rotation of the rotor.