Abstract: An anti-cogging apparatus includes a first support member, a second support member, a first set of magnets, and a second set of magnets. The first support member is configured to be connected to and rotate with a rotatable shaft. The second support member does not rotate and is configured not to move with the first support member. The first set of magnets is mounted on the first support member in an alternating polarity or a non-alternating polarity configuration. The second set of magnets is mounted on the second support member in an alternating polarity configuration or a non-alternating polarity configuration. The first set of magnets magnetically interacts with the second set of magnets to provide an anti-cogging torque on the rotatable shaft.

Abstract: A brushless motor is provided including: a rotor housing including a circular-cylinder-shaped bearing housing portion and an outer cylinder portion; a rotor magnet provided at an inner peripheral face of the outer cylinder portion; a bearing housed in the bearing housing portion and assembled to a motor shaft; a stator core including a ring-shaped core main body provided in the radial direction between the bearing housing portion and the rotor magnet and a ring-shaped wall portion formed in a ring-shape along an inner peripheral portion of the core main body, extending from the core main body inner peripheral portion towards the radial direction inside, and facing one opening of the bearing housing portion; and a center piece including a main body portion facing one opening of the outer cylinder portion, and a close contact portion closely contacting in the stator core axial direction with the ring-shaped wall portion.

Abstract: The invention relates to a method for absorbing the displacement, under the influence of an external force, of at least one plunger (10,20) in a linear electrodynamic motor comprising a least an induction coil (11, 21) magnetically coupled with the plunger. Said method comprises the steps of: detecting in said induction coil a current induced (I?ind) amplified relative to the induced current. The invention can be applied to cryogenic machines on board space ships.

Abstract: The invention relates to the construction and a mode of operation of statorless electronically switched DC motors that have two freely turning rotors. The invention also relates to embodiments of the invention regarding the bearings, the circuit design and the mode of operation of machines such as fans and blowers.

Abstract: A portable motor powered device capable of operating on a cordless battery pack as well as a corded power pack, yet enabling to reduce the size and weight of the corded power pack to be truly compatible with the corded battery pack in size and weight. The device has a housing accommodating therein a DC motor as a power source. The cordless battery pack is detachably connected to the housing and has a battery which supplies a low DC voltage for operating the DC motor. The corded power pack is detachably connected to the housing and supplies a high DC voltage for operating the DC motor. The corded power pack includes a power cord adapted to be connected to receive an AC source voltage and a converter for converting the AC source voltage into the high DC voltage. The DC motor has a rotor provided with first and second windings which are selectively connected to receive low and high DC voltages respectively from the cordless battery pack and the corded power pack.

Abstract: An ultrasonic transducer is formed by a plurality of cMUT cells, each has a charged diaphragm plate capacitively opposing an oppositely charged base plate. The diaphragm plate is distended toward the base plate by a bias charge. The base plate includes a central portion elevated toward the center of the diaphragm plate to cause the charge of the cell to be of maximum density at the moving center of the diaphragm plate.

Abstract: A two-speed permanent magnet D.C. electric motor has a housing, permanent magnets carried by the housing, and an armature assembly installed in the housing. The armature assembly has a shaft rotatably mounted in the housing, first coil windings, a first commutator connected to the first coil windings, second coil windings and second commutator connected to the second coil windings. A first set of brushes is carried by the housing and engages the first commutator for applying a D.C. voltage to the first coil windings to cause rotation of the armature assembly at a first speed. A second set of brushes is carried by the housing and engages the second commutator for applying the same D.C. voltage to at least the second coil windings to cause rotation of the armature assembly at a second speed.

Abstract: A 1-phase energized disk-type brushless motor or fan motor comprises a single position detecting element located at a position on a printed circuit board corresponding to one of magnetically active conductor portions of one of stator coils of the stator armature. The magnetically active conductor portions include a width substantially equal to the width of each pole of the magnet rotor. A cogging generating magnetic member or plate having a width substantially equal to the pole width is located on the printed circuit board such that it is spaced by about three fourths of the pole width from one of the conductor portions of one of the stator coils so that the magnet rotor may stop with one pole thereof just opposed to the magnetic member, thereby assuring self-starting of the motor and uniform turning torque over the entire rotation of the motor.

Abstract: A rotational speed signal sensor for a motor having a rotating permanent magnet as a rotor. One cylindrical surface of a hollow cylindrical rotating magnet has a series of magnetic poles which coact with the stator windings so as to produce the torque while the other cylindrical surface of the rotating magnet has a series of magnetic poles which coact with a sensor coil so as to derive the rotational speed signal.

Abstract: In an induction and universal motor combined in a common lamination stack and supplied from a single phase line in line with a single armature winding system common to universal commutator motor as well as to induction motor operation, there are connected to the same segments of the commutator a crossed lap winding and an uncrossed lap winding, the coil span of which corresponds approximately to one pole pitch of the low pole and, in particular, two pole commutator stator winding and to an uneven integral multiple of the high pole induction motor stator winding, to provide a motor particularly suited for driving automatic washing machines.

Abstract: An improvement in DC rotary machine is disclosed. The stationary field yoke of the DC rotary machine has a cylindrical field member and a cylindrical bearing member of a smaller diameter than that of the field member. These members are made of oil-containing sintered alloy as a unitary member. The inner cylindrical surface of the bearing part of the stationary field yoke supports a rotary shaft rotatably therein. A motor coil assembly in a shape of cup is fixedly mounted on the rotary shaft. A generator coil assembly is also formed in a shape of cup which has a central opening in the botton wall of the cup. The diameter of the central opening is approximately equal to the outer diameter of the bearing part of the stationary field yoke.

Abstract: The present invention relates to a dynamo-electric machine which includes a plurality of permanent magnets arranged sequentially with like poles adjacent and spaced from each other by a plurality of spacers of magnetically soft material. Motive coils are located generally adjacent to the permanent magnets so that when energized one pole of the induced magnetic field will provide attractive forces toward one of the permanent magnets while the opposite pole of the induced magnetic field will produce repulsion forces from the like pole of the adjacent permanent magnet. A commutator device is provided for properly energizing selected ones of the motive coils in proper polarity. A plurality of generator coils are located adjacent to the permanent magnets for cutting the magnetic lines of flux emanating therefrom so as to generate an induced voltage at an output thereof responsive to the relative motion between the generator coils and the permanent magnets.

Abstract: A direct-current motor-generator comprises at least one stationary magnetic circuit including a permanent magnet and forming an air gap of substantially cylindrical shape, and a generally cup shaped rotor bearing a motor winding and a generator winding. The arrangement of the at least one magnetic circuit and the windings is such that the magnetic flux passing through the one of the said windings is separated in space from the flux passing through the other of the said windings.

Abstract: A completely sealed magnetically driven pump having a piston armature driven by electrical windings. Unique electrical driving circuits are provided for the pump embodying feedback windings magnetically coupled with the driving windings of the pump for controlling the reciprocation. The drive circuits are such as to facilitate driving rates, embodying particularly solid state bistable flip-flop components adaptable to be embodied in or associated with computers or other low power logic devices.