Abstract: A slot insulating magnetic wedge inserted into the vicinity of the center of an opening portion of a stator slot, the slot insulating magnetic wedge being contacted with an inner surface of the stator slot of a motor. The slot insulating magnetic wedge comprises a non-magnetic insulating thin leaf shaped material and a magnetic material layer laminated on at least one surface of the non-magnetic insulating thin leaf shaped material, the electric resistance of the magnetic material layer being in the range from 10 .mu..OMEGA..cm to 200 .mu..OMEGA..cm. The magnetic material layer comprises an amorphous magnetic alloy thin film, a Fe-based magnetic alloy thin ribbon having ultra fine crystalline particles, a crystalline magnetic alloy thin ribbon, a crystalline or amorphous magnetic alloy thin film produced by thin film forming technologies, or the like. The magnetic material layer with the electric resistance in the range from 10 .mu..OMEGA..cm to 200 .mu..OMEGA..

Abstract: The submersible propulsor unit of the invention comprises a cylindrical shroud having a water inlet and a water outlet, a propeller having a hub rotatably mounted within the shroud on a shaft, and an electric motor for driving the propeller that includes a rotor mounted around the periphery of the propeller, and a stator circumscribing the shroud, and a bearing assembly that includes means for circulating ambient water around the bearing surfaces to both lubricate and cool them. A stationary cover is detachably secured over the bearing assembly on the water inlet end of the shaft to provide easy access to the bearings in the bearing assembly The vane members that concentrically mount the shaft within the interior of the shroud are, in one embodiment, all connected on the downstream side of the propeller to reduce the cavitation and resulting noise when the propeller rotates. The magnetization of the rotor is provided by a plurality of permanent magnets for both improved efficiency, and lower noise.

Abstract: A diametral runout reducer adapted to drive a rotor for exciting a stator of a speed sensor located in a differential carrier. The rotor is driven by a diametral runout reducer. The runout reducer includes an annular axially extending member having a first end which engages a vehicle axle shaft driven by the differential case and a second end which drives the rotor. Intermediate the first and second end of the runout reducer is a radial protrusion disposed proximate the second end defining a peripheral surface which extends equidistantly from a central point. The rotatable axially extending flange defines a bore whose central axis is maintained coincident with a preferred axis of rotation by means of bearings supporting the differential case. The bore has a dimensional interrelationship with a radial protrusion which facilitates sliding, thereby maintaining the central point of the annular axially extending flange coincident with the preferred central axis.

Abstract: A DC brushless motor for use in various kinds of electric appliances comprises a rotor portion, and this rotor portion includes a rotating shaft and a cylindrical permanent magnet which is rotated with the shaft. A stator portion is provided opposite to the rotor portion, and includes an armature which is located at the inner side of the cylindrical permanent magnet so as to be opposite to and coaxial with the magnet. The armature is provided with a plurality of coils on its peripheries, and has an annular shape as a whole. A circuit board is disposed to be substantially perpendicular to the axis line of the rotating shaft, and the armature is supported above the circuit board. The rotating shaft terminates substantially at the middle of the height of the motor, thus leaving a space between the rotating shaft and the circuit board.

Abstract: The dynamoelectric machine has endwindings including a plurality of superposed conductor bars 22 and adjacent end turns 20. Rabbets 32 are formed along the undersides of the adjoining conductor bars and end turns to receive portions 34 of gussets 30, remaining portions 35 of the gussets projecting to one side of the joint. The conductor bars and end turns have grooves 38, 36 forming cooling passages with ports 42, 40 opening to one side of the joint short of the joint. The gusset 30 has a barrier 44 spaced from the joint and forms with the ports a cooling channel 46 between the ports for transporting cooling gas between the cooling gas channels of the conductor bars and end turns.

Abstract: A roller thrust bearing structure rotatably supports a spindle shaft on a frame and includes a circular table which is fixed to the spindle shaft as a flange. A radial bearing is fixed on the frame for rotatably supporting the spindle shaft in a radial direction of the spindle shaft. A support member is located between the table and the frame for rotatably supporting the table on the frame so as to support the spindle shaft in a thrust direction of the spindle shaft. The thrust direction is perpendicular to the radial direction of the spindle shaft. The roller thrust bearing structure for a spindle shaft is used in a thin disc drive.

Abstract: A control apparatus of a magnetic bearing controls electromagnets so that both a displacement deviation of a center of gravity of a rotary shaft and an angle of twist around the center of gravity of the rotary shaft become 0, thereby supporting the rotary shaft in space by the magnetic force of the electromagnets. The apparatus includes .theta..sub.X and .theta..sub.Y control devices for controlling angles .theta..sub.X and .theta..sub.Y of twist of the two degrees of freedom of a rotational motion orthogonal to each other around the center of gravity and perpendicular to an axial direction of the rotary shaft, a cross feedback being produced so that both a feedback signal of the rotary angle .theta..sub.X and a feedback signal of the rotary angle .theta..sub.Y are respectively fed back as cross feedback signals to the .theta..sub.Y and .theta..sub.X control devices. A rotational speed detecting device for detecting a rotational number of the rotary shaft.

Abstract: A scanning motor having a bracket, a shaft member secured to the bracket, a rotor rotatably supported by the shaft member via a pair of bearings and a polygonal mirror fastened to the rotor, the polygonal mirror being disposed at a position on the outside of either of a pair of the bearings. The rotor has a rotor body and a yoke member which constitutes a balance adjusting groove in cooperation with a frequency generating magnet fastened to the yoke member. A motor having a bracket, a rotor, magnetic force generating means disposed in the bracket, magnetic flux changing means fastened to the rotor, sensing means for sensing change in the magnetic flux taken place in a magnetic circuit constituted by the magnetic force generating means and the magnetic flux changing means and a covering member for covering the magnetic force generating means.

Abstract: An industrial heat dissipating electric fan comprising a metal shaft tube to combine with a stator, the metal shaft tube having an annular groove for inner projecting ridges of a central shaft tube of a housing base to engage to combine firmly and securely related components.

Abstract: A spindle motor able to reduce leaking of magnetic flux of an index magnet to a magnetic head of a disc apparatus. In an axial gap type spindle motor having a rotor case rotatably supported by a base plate, an index magnet is provided to a face of the rotor case opposite to the base plate. A hall device is provided in an open space between a plurality of coils arranged radially on the base plate at a position opposite to the index magnet. A magnetic flux forms a closed loop by passing through the rotor case, and thus leaking of magnetic flux to the outside is reduced.

Abstract: A brush bridge assembly for an electric motor an electrically insulating carrier body having a base plate having opposite inner and outer surfaces and a generally circular perimeter; and a cylindrical side wall extending axially from the perimeter of the base plate. The brush bridge assembly further has a plurality of brush guides supported on the inner surface of the base plate; a carbon brush supported in each brush guide for a radial displacement relative to a central axis of the carrier body; a spring connected to each carbon brush for urging the carbon brush radially inwardly; supporting elements mounted on the inner surface of the base plate in a uniform distribution; heat generating electric components and fixed contact terminals held in the supporting elements.

Abstract: A magnetic disc drive motor comprises a hub for carrying magnetic discs on its outer periphery, a drive magnet rigidly fitted to the inner periphery of the hub, a stator core having a coil wound around it and juxtaposed with the drive magnet and a motor frame having a substantially cylindrical holder for rigidly holding the stator core, wherein the space between the stator core and the motor frame is filled with a resin material. A compact and simply configured magnetic disc drive motor can thus be realized, which is capable of rotating magnetic discs in a very stabilized manner.

Abstract: An actuator has teeth for providing large forces to an object to be moved without experiencing slipping or sliding on the surfaces of the actuator or object. The actuator moves in smooth walking cyclic steps, first engaging the object by meshing the actuator's teeth with the teeth of the object, while moving at the same speed as the object, moving the object, retracting from the object while moving at the same speed as the object, and then retracing to its beginning position for starting a new cycle. The controller for the actuator obtains information about the relative position of the teeth for smoothly meshing the teeth and moving the object. The controller precisely moves the actuator for proper tooth meshing by using mechanical summing of actuator layers, each receiving electrical impulses of a precise number of waves of a known wave form.

Abstract: Labyrinth disks, which are integral components of an electric motor, provided in the front and rear portions of the motor and/or the rotational speed detecting gear, which also is an integral component of the motor, of a rotational speed detector for detecting the rotational speed of the output shaft of the motor are employed for balancing the motor.The labyrinth disks and the rotational speed detecting gear are provided at the outer surfaces thereof with a plurality of internally threaded holes. An imbalance in the motor is measured after completely assembling the motor, and then a balancing screw is screwed into the internally threaded hole to an appropriate point, to thereby balance the rotary unit of the motor.

Abstract: A method of driving a piezoelectric bimorph device in which first and second piezoelectric ceramic layers are so electrically connected to each other as to expand or contract in the opposite directions, which is characterized in that when t.sub.1 is taken as the thickness of one of the first and second piezoelectric ceramic layers, Ec is taken as the coercive field strength of a piezoelectric material constituting the piezoelectric ceramic layer, and V.sub.1 is taken as the minimum value of the produce Ec.times.t.sub.1 =Vc.sub.1, and t.sub.2 is taken as the thickness of the other piezoelectric ceramic layer, Ec is taken as the coercive field strength Ec of a piezoelectric material constituting the piezoelectric ceramic layer, and V.sub.2 is taken as the minimum value of the produce Ec.times.t.sub.2 =Vc.sub.2, a voltage of not less than (V.sub.1 +V.sub.2) is applied to said piezoelectric bimorph device.

Abstract: A method and device for precisely driving a rotary object includes a motor ounted in a housing and a reduction device comprising first and second harmonic drives, which connect the motor to the object to be driven via an output shaft. The output shaft is connected to the object to be driven via an adapter cup and a bellows which is stiff in torsion but which tolerates misalignments between the drive device and the object. All elements are designed to maximize stiffness and precision and to minimize backlash while maintaining maximum concentricity between the elements.

Abstract: An AT-cut quartz crystal for a quartz crystal microbalance has a buffer layer sandwiched between an adhesion layer and an electrode layer on the front or deposition side of the crystal. The buffer layer can be a zinc layer of 6000 .ANG. sandwiched between a titanium or chromium adhesion layer of 100 to 160 .ANG. and a gold, silver, or aluminum outer electrode layer of about 2000 .ANG.. The zinc layer has a relatively low bulk modulus, and absorbs stress imposed by the deposited layer. The buffer layer prolongs useful crystal life, particularly when depositing dielectric materials. The crystal should have a modest surface roughness as keying-in structure.

Abstract: An assembly in which a rotating shaft is supported by a magnetic bearing has a backup bearing to support the shaft in the event of failure of the magnetic bearing. If the bearing portion of the backup bearing comprises a ball race, the radially outer raceway thereof is secured to an anchorage, such as a housing for the assembly. A low stiffness damper member in the form of an annular shaped body of resilient material also is included in the backup bearing, between the bearing portion thereof and the anchorage. Advantageously, when the magnetic bearing has failed, and the shaft is being brought to rest by being in contact with the backup bearing, the resilient body is in shear, and the body has a lower stiffness than otherwise would be the case. Thus, any tendency for the backup bearing, and/or the anchorage, to be damaged while the shaft is being brought to rest, is reduced, because the provision of the low stiffness damper causes the shaft to have a low natural frequency of oscillation.

Abstract: A metal-filled gaphite brush used for a miniature motor, which has a permanent magnet field and is caused to rotate through current commutation via a commutator, formed by bonding graphite powder and used for making sliding contact with the commutator for current commutation, in which the metal-filled graphite brush is formed by pressure-forming and sintering a mixture of highly purified graphite powder and metal powder; the graphite powder used for the metal-filled graphite brush being purified to reduce the ash content thereof 0.05 wt. %, and the method of making the same.

Abstract: A revolving field electric motor including an armature attached to a shaft which armature is driven to rotate about the shaft, thus causing the shaft to turn. Permanent magnets are disposed on opposite ends of the armature. In place of field magnets of conventional motors which are energized all the time, individual electromagnets are evenly spaced around the perimeter of the circle inscribed by the armature. Opposing magnets are switched on only when the armature magnets approach, and are switched off as the armature magnet is attracted to and passes by the energized magnet.