Abstract: A cooling device for an electric motor includes a plurality of inwardly projected stator poles arranged in a circumferential direction such that an axially extending space is defined between two adjacent stator poles. Coils are wound on the respective stator poles and coolers are disposed in the respective spaces such that each of the coolers is in thermal contact with its neighboring coils.

Abstract: An improved micromachined structure used for beam scanners, gyroscopes, etc. includes a reference member from which project a first pair of axially aligned torsion bars. A first dynamic member, coupled to and supported from the reference member by the torsion bars, oscillates in one-dimension about the torsion bar's axis. A second dynamic member may be supported from the first dynamic member by a second pair of axially aligned torsion bars for two-dimensional oscillation. The dynamic members respectively exhibit a plurality of vibrational modes each having a frequency and a Q. The improvement includes means for altering a characteristic of the dynamic member's frequency and Q. Coupling between dynamic members permits altering the second dynamic member's frequency and Q by techniques applied to the first dynamic member. Some techniques disclosed also increase oscillation amplitude or reduce driving voltage, and also increase mechanical ruggedness of the structure.

Abstract: A microengine uses two synchronized linear actuators as a power source and converts oscillatory motion from the actuators into constant rotational motion via direct linkage connection to an output gear or wheel. The microengine provides output in the form of a continuously rotating output gear that is capable of delivering drive torque at a constant rotation to a micromechanism. The output gear can have gear teeth on its outer perimeter for directly contacting a micromechanism requiring mechanical power. The gear is retained by a retaining means which allows said gear to rotate freely. The microengine is microfabricated of polysilicon on one wafer using surface micromachining batch fabrication.

Abstract: A torque motor includes an annular, cylindrically symmetric support base, and a plurality of electromagnet coils affixed to the support base at regular intervals around a cylindrical circumference of the support base. There is additionally an annular, generally cylindrical, rotationally movable rotor ring overlying the support base and having an inner surface, and a plurality of permanent magnets affixed to the inner surface of the rotor ring at regular intervals around a cylindrical circumference of the rotor ring. The number of permanent magnets is even and equal to the number of electromagnet coils, and the permanent magnets are arranged in alternating polarities around the circumference of the rotor ring. In a preferred form, there are six of each type of magnet, spaced equidistantly around the circumference of the respective rings.

Abstract: The invention concerns feed-forward, linear, radio-frequency amplifiers, which contain components which can be grouped into two categories: active and passive. Under the invention, all active components are constructed as two-port devices, which are easily tested, using standard equipment, in order to locate malfunctions. The active components plug into a network of the passive components, comprising striplines, waveguides, coaxial cables, and the like.

Abstract: An electrical machine with a stator and a rotor rotatable about an axis of rotation and having no bearing elements rotatably mounting the rotor relative to the stator or for defining the axis of rotation of the rotor is provided with means for releasably securing the rotor in position relative to the stator. The rotor can be secured relative to the stator in the axial and radial directions. Rotation of the rotor relative to the stator can also be prevented.

Abstract: A permanent magnet motor rotor arrangement including a rotor core having radial and angular positioning surfaces provides for inexpensive and precise positional control of rotor components.

Abstract: A CMOS buffer amplifier can accept input signals and produce output signals that are within one half of the enhancement threshold voltage of the power supply voltages. These characteristics make this buffer amplifier ideal for use with low voltage CMOS circuitry with sub-micron geometries. The buffer amplifier contains two differential amplifiers, the output of both being combined and coupled to an output node. Each differential amplifier has matched input transducing devices on each of its inputs. One of these couples the input of the buffer amplifier to one of the inputs of the differential amplifier, while the other one couples the output of the buffer amplifier as feedback to the other side of the same differential amplifier. The pair of input transducing devices providing input to one differential amplifier are matched and suitable for operation in a higher voltage range than are the matched pair providing input to the other differential amplifier.

Abstract: The coil (1) of the motor includes a coil body carrying two flanges (7, 8). Made in one piece with one of the flanges (8), a plate (10) covers a lug (4) of the core. This plate (10) acts as anchoring point for the output wires (11, 12) of a wire winding (9) by embedding of the end zones (13, 14) of each of said wires in the plate. Prior to reaching the end zones (13, 14), the wires (11, 12) follow a channel (15) made in the plate, a hole (16, 17) arranged perpendicular to the wires and ending in this channel, being made both in the plate and in the lug.

Abstract: An external power head is energized by a motor causing movement of an element that produces a varying magnetic field, thereby inducing power in an implanted receiver coil within a patient's body. The external power head includes either one or more moving permanent magnets, or one or more moving elements that vary the magnetic flux coupled to the implanted receiver coil. As a result of the varying magnetic field experienced by the implanted receiver coil, an electric current flows from the implanted receiver coil to energize an implanted medical device.

Abstract: A movable member of the present driving device comprises a magnetized part, or more than one magnetized parts having all the same direction of magnetization, which is perpendicular to the direction of movement. Each magnetized part is moving in at least two air-gaps of a closed magnetic circuit coupled with en energizing coil. The material of the magnetized parts has a linear demagnetization characteristic up to temperatures at least equal to 100.degree. C. and at least up to a negative value of the flux density equal, in absolute value, to 0.5 times the remanence of the magnetic material. The driving device is dimensioned so that the mean operating point of each magnetized part lies at a flux density value smaller than 0.5 times the value of the remanence of the magnetic material used. The volume of magnetic material can be substantially reduced for a given force or torque to be delivered.

Abstract: An amplifier circuit with improved turn-on and turn-off transient operation includes a differential amplifier and a selectively variable reference generator for controlling the amplifier output during circuit turn-on. The amplifier has differential inputs which are driven by a reference voltage from the reference generator and a single-ended input signal. During circuit turn-on, the selectively variable reference voltage, generated by charging the bypass capacitor with a constant current source, charges in a linear manner from ground potential toward its final value of, typically, half of the power supply voltage. During circuit turn-off, the bypass capacitor is discharged with a constant current source in a linear manner toward ground potential. This allows improved turn-on and turn-off transient operation to be realized, e.g.

Abstract: An stable inverted amplifying circuit includes an odd number of CMOS inverters and a feedback capacitance. Balancing resistances decrease the inverter open gain and limit the gain of the entire circuit. Serial capacitances act to prevent low-frequency oscillation. Oscillation-preventing circuits are also provided to reduce high-frequency oscillation. Sleep, refresh, and sleep-refresh switches are used to cancel residual loads and reduce power consumption.

Abstract: This invention provides a novel switched reluctance machine and a method of its control. The machine rotor has rotor poles that are wider than the stator pole, which allows two phases to be energized simultaneously, reducing torque ripple and noise.

Abstract: A bipolar OTA having a wide input voltage range is provided without increasing the circuit scale and current consumption. This OTA includes a first differential pair of emitter-coupled first and second bipolar transistors, a second differential pair of emitter-coupled third and fourth bipolar transistors, a common current source or sink connected to the coupled emitters of the first to fourth transistors. The first to fourth transistors are driven by a common tail current produced by the common current source or sink. A first input voltage as an input signal to be amplified is differentially applied across the bases of the first and second transistors. A second input voltage, which is produced by attenuating the first input voltage, is differentially applied across the bases of the third and fourth transistors. First and second dc offset voltages are applied to the bases of the third and fourth transistors, respectively.

Abstract: A micromachined stepper motor having a toothed slider connected at either end to spring flexures. At least one of the spring flexures is positioned between a load, such as a high pass optical filter, and the slider. The slider is positioned within three stators that are sequentially energized such that they move the slider along its longitudinal axis. The springs and guide posts hold the slider in place and establish a rest position when no driving force is applied.

Abstract: A cascode single-ended to differential converter has particular applications for use in communication, e.g. RF circuits. The converter provides higher gain, reduced noise figure and improved output level and linearity over the prior art differential pair converter. The present converter is a transconductor, converting an input voltage to a differential current output signal, i.e., two output signals of different currents, with the difference being linear to the level of voltage. The cascode amplifier output signal is used to produce a signal equal in the amplitude but 180 degrees out of phase with the signal produced by the cascode amplifier.

Abstract: A magnetic bearing for active centering about at least one centering axis of a second body mobile relative to a first body has a first portion including two parallel ferromagnetic plates, a first core carrying a first coil and permanently magnetized means magnetized perpendicularly to the ferromagnetic plates, said first mounted between said ferromagnetic plates. The bearing has a second portion separated from the ferromagnetic plates of the first portion by a pair of airgaps of variable thickness parallel to the centering axis. The permanently magnetized means are offset relative to the core in a direction substantially parallel to the pair of airgaps and the ferromagnetic plates are provided with notches facing the permanently magnetized means and oriented transversely to the pair of airgaps.

Abstract: Electromagnetic shielding apparatus is provided for a motor having a rotor and a stator wherein the shielding apparatus is characterized by the absence of an electromagnetic shield in the stator of the motor.

Abstract: An improved chopper stabilized operational amplifier is disclosed, along with an improved method of timing the switchings of chopper switches in such an amplifier. The disclosure includes an integrated circuit and method for generating a true random voltage signal having a truly random RMS voltage value within a selected range. The true random voltage signal is obtained by amplifying and bandpass filtering random white noise voltages generated by a component of the circuit. The white noise voltages include shot noise voltages generated by bipolar transistors in an input amplifier stage. The random signal generator circuit and method is employed with an oscillator to form a random clock signal generator on the integrated circuit chip. The amount of time between each clocking pulse output by the random clock signal generator truly randomly varies within a selected range of time, and repeats only by random chance.