Abstract: A pneumatic and magnetic bearing type motor provides a hollow rotary member fitted rotatably on a stationary shaft, radial pneumatic bearings having dynamic pressure generating grooves formed on one of the stationary shaft and hollow rotary member, supporting the hollow rotary member in a radial direction with the aid of dynamic pressures generated, and a thrust magnetic bearing supporting the hollow rotary member in a thrust direction thereof. In the motor, the position where the hollow rotary member is supported by the thrust magnetic bearing is substantially coincident with the equilibrium point where moments of the pressures are equal, whereby the motor is substantially free from vibration during operation, and the bearings are substantially prevented from being damaged when the motor is started or stopped.

Abstract: An electric synchronous motor having a stator (10) with electric windings (14) and a rotor (16) which comprises a spindle (20) and a magnetic core (22), wherein the core (22) is formed by a number of annular magnetic discs (21) piled on the spindle (20) and having a length-to-diameter ratio exceeding 3. The discs (21) are insulated electrically from each other by layers of an inorganic material (17), such as an aluminum foil layer which is oxidized on both sides, and are axially clamped between shoulders (23, 24) on the spindle (20) to a high prestress level for obtaining a high bending strength, i.e. a higher coefficient of elasticity, of the rotor (16) as a whole.

Abstract: An electrostatic actuator according to the present invention includes a first member having a plurality of striped electrodes insulated from one another and arranged in a prescribed direction with a prescribed spacing between them, a second member having a plurality of striped electrodes insulated from one another and arranged in a prescribed direction with a prescribed spacing between them, and continuous-waveform polyphase AC power supplies applied to the electrodes of the first member and the electrodes of the second member, one or both of the first member and second member being moved by an electrostatic coulomb force between the first member and the second member.

Abstract: A brush device includes elliptic compression coil springs, an electrical conductive member, rotary shaft, and brushes pushed against an electrical conductive member on the rotary shaft with the elliptic compression coil springs. And the outer end parts of each of the elliptic compression coil springs are bent inwardly of the ellipse formed by the elliptic compression coil spring.

Abstract: A miniature motor in which stators are mounted in an interior of a casing, and a preassembled commutator is provided on a rotor rotatably disposed to face the stators. The commutator has a sleeve body having a cylindrical portion provided with a flanged portion and a plurality of recesses, directed outwardly, in a side wall of the flanged portion, with the sleeve body being made of insulating material and mounted on a rotary shaft of the rotor. The commutator also has a plurality of conductive commutator pieces each having a body portion formed in an arcuate shape and mounted on an outer circumferential surface of the cylindrical portion, a terminal portion and at least one retainer portion, with each of the terminal portion and the retainer portion being received in the recesses.

Abstract: A soft switching circuit gradually connects an audio signal to zero reference level to mute the audio signal, or connect a filter to enable the filter. A MOSFET is connected between the audio signal and the zero reference level. A resistor-capacitor circuit is connected to the gate of the MOSFET and receives the MUTE or FILTER* signal from the computer system. When the MUTE or FILTER* signal changes condition, the RC circuit provides a signal to the MOSFET gate that changes relatively gradually. Consequently, the drain-to-source resistance of the MOSFET also changes from short circuit to open circuit or vice versa relatively gradually.

Abstract: A squirrel-cage rotor (10) includes a laminated core (14) fixed to a rotor shaft (12), a plurality of secondary conductors (18) arranged respectively in a plurality of through holes (16) formed through the laminated core (14), a pair of end rings (20) connected to the secondary conductors (18) at axial ends of the laminated core (14), and a pair of reinforcing members (22, 23) respectively covering the end rings (20). The secondary conductors (18) and the end rings (20) are integrally formed through a casting process, and are connected with the laminated core (14) and the reinforcing members (22, 23).

Abstract: Horizontal-axis electrical machine having a stator laminate core (1) which is arranged in a housing (2, 3) which is split horizontally, which stator laminate core (1) is clamped by means of fastening wedges (35), which are distributed over its circumference, in supporting rings (32), which are arranged orthogonally to the machine longitudinal axis and are spaced apart from one another. The supporting rings are connected on their external circumference, via fastening parts (39, 40), to the housing lower part (2) of the machine. The supporting rings (32) have azimuthal fastening plates which run symmetrically with respect to the vertical plane of symmetry of the machine.In order to decouple the stator laminate core (1) from the housing lower part (2), the fastening plates (40) are fastened to the said supporting rings such that they are sprung horizontally in the radial direction, the fastening plate (40) itself being constructed as a leaf spring, or acting as such.

Abstract: The brushless DC motor comprises at least one multi-pole composite magnet which functions as a rotor, at least one stator member which determines the angular position of this rotor, means for positioning the rotor(s) and the stator member(s) on a common axis, a sensing device for determining the position of the composite magnet relative to the stator member(s), and means for determining the magnetic configuration on the stator member. The composite magnet comprises two sections, each section having a plurality of projections and apertures. The projections and apertures on a first section mate with the apertures and projections, respectively, on the second section. The first and second sections are magnetized in opposite axial directions. In one embodiment, each stator member has a plurality of pole pieces which are positioned in operative relation to the composite magnet. Two windings are formed on each stator member.

Abstract: A switching regulator having a series resonance push-pull converter (GW) and two clocked boost regulators (AR1, AR2) connected in series with the converter, wherein: the converter comprises a transformer (Tr) having two primary windings (w1, w2) which are galvanically isolated from one another, and two push-pull switches (S1, S2) each connected in series with a respective one of the primary windings; each of the boost regulators comprises a series inductance (L1, L2) and an output capacitor (C1, C2); and the boost regulators are connected to the converter to form two push-pull branches, each of the push-pull branches being composed of the series inductance of one of the boost regulators connected in series with a respective one of the primary windings and a respective one of the push-pull switches, and the output capacitor of each of the boost regulators constituting a resonance capacitor of the converter.

Abstract: When mounting the winding ends of a stator winding in a dynamo, at least an outer ring of synthetic resin saturated cord ring is wound in multiple windings on the winding ends in its plastically deformable state. The synthetic resin does not harden until after the cord ring is affixed. The outer ring is adapted to be installed in the cramped winding head space and is especially suitable for retrofitting purposes.

Abstract: A parallel operation controller for power converters which performs parallel operation control of a plurality of power converters having input terminals connected to a DC voltage source and output terminals connected to each other through reactors. The parallel operation controller includes: three-arm modulation control signal generating devices for generating three-arm modulation control signals each serving as a voltage command value for each phase of corresponding power converters; a voltage fixing period determining circuit which selects, on the basis of a three-arm modulation control signal from one of the three-arm modulation control signal generating devices, a phase fixing the voltage level thereof to a predetermined DC voltage level, and determines a period in which the voltage level is fixed. This parallel operation controller reduces the amount of circulating currents which flow between phases of unit inverters.

Abstract: One PWM control circuit is located in the primary side of a power converter and is isolated from the secondary side, and another PWM control circuit is located in the secondary side of the converter and is isolated from the primary side. The first PWM control circuit is powered by a direct tap to the input line of the converter and, during start-up, supplies a low power square wave coupled directly to switching transistors of an inverter of the power converter. After start-up, the second PWM control circuit is powered by a direct tap to the secondary side and supplies a regulating square wave output to the switching transistors through an isolation component such as a coil. After start-up, the primary PWM control circuit is disabled so that, under normal operating conditions, the power supply is regulated only by the second PWM control circuit.

Abstract: A phase adaptable AC/DC converter having three input terminals capable of connection to either a single phase or dual phase electrical power service. A feedback circuit in a control portion of the converter sums a first voltage and a second voltage which are proportional to first and second output voltages, respectively, to control a first bidirectional switch in a voltage boost circuit. The feedback circuit also sums the first and second voltage with a difference between the first and second output voltages to control a second bidirectional switch in the voltage boost circuit.

Abstract: An electrical machine having a stator formed from a pair of cup-shaped permanent magnets symmetrically disposed on opposite sides of a conductive, disk-shaped rotor. The magnets are polarized such that a portion of their external magnetic flux passes in one direction through a short peripheral gap formed by the magnets in which the periphery of the rotor is disposed. The remainder of the external magnetic flux substantially passes in the opposite direction through a cavity defined by the inner volume of the cup-shaped magnets. The inner portion of the disk-shaped rotor is disposed in this cavity. One embodiment of the invention implements the cup-shaped magnets with modified "magic spheres" mounted on either side of the conductive disk-shaped rotor. Other embodiments use a magnetic plate on one side of the disk-shaped rotor to act as a magnetic mirror for a cup-shaped magnet mounted on the other side of the rotor.

Abstract: A single speed, two pole permanent magnet motor has compact brush card assembly mounted within the volume form by a plurality of ring shaped laminations forming the armature to allow the height of the motor to much less than a standard motor. In addition, there is shown a two speed, four pole permanent magnet motor having a height much less than a standard two speed motor. In each motor there are electrically connected to the supply lines a choke means and across each supply line is a capacitor for suppressing radio frequency interference.

Abstract: A switched reluctance motor includes a stator having a central bore for rotation of a rotor therein. The stator has four equally spaced teeth extending radially inwardly from the yoke of the stator to define the central bore. A rotor assembly for rotation in the central bore of the stator is included. The rotor assembly has three teeth extending radially outwardly from the central axis of the motor to terminate in close proximity to the stator teeth. Stator windings associated with the stator teeth generate a magnetic field in the central bore to cause rotation of the rotor assembly.

Abstract: Conformable distance blocks assemblies (24, 26) are provided for spacing adjacent end windings (20, 22) in a dynamoelectric machine. Each block assembly includes a pair of relatively hard blocks (28, 38) straddling a deformable spacer (32). The blocks and spacer are wrapped with an electrically insulating tape (34, 48) having an adhesive along an interior face for maintaining the blocks and spacer in assembled condition with a tab (36, 50) on the end of the tape. Generally rectilinear blocks (28) are employed for axial distance block assemblies, while the circumferential block assembly is comprised of tapered blocks (38) forming a wedge assembly. In installation, the assemblies are disposed between adjacent end windings, resiliently deforming the spacer, the tab being adhesively secured to the outermost lamination of the end windings. The spacer is also impregnated with a resin such that, upon curing, a rigid distance block assembly is provided to maintain adjacent end windings spaced from one another.

Abstract: In a dynamoelectric generator, a low-resistance electrical contact is provided by using a spring below the rotor slot wedges to bias the wedges against the overlapping retaining rings. This biased contact between the wedges and retaining rings forms a conductive current path for high-frequency eddy currents induced on the surface of the rotor and retaining rings at all operating speeds and at rotor standstill. In addition, the spring reduces gauling between the rotor key slots, wedges and retaining ring.

Abstract: An improved electric motor casing is disclosed. The end casing includes a circular end plate and perpendicular peripheral side wall with a plurality of rectangular, internally projecting lands formed in the side wall. Each land defines a linear ledge with the plurality of linear ledges disposed in the same plane to receive and support the electric motor stator. The casing is formed by drawing a flat metal blank into the end plate and perpendicular side wall, with the plurality of rectangular lands drawn substantially simultaneously with formation of the end plate and perpendicular side wall.