Abstract: A large number of teeth are formed on the outer circumference of a rotor. A stator is disposed around the rotor. The stator has multiple magnetic poles whose number is n times the number of phases. Each pole has formed on its surface a plurality of teeth at a pitch equal to the rotor tooth pitch. The teeth mounted on the adjacent magnetic poles are selected to deviate in pitch one-half or thereabout from the rotor teeth and the adjacent poles are to be opposite phases from each other.

Abstract: A temperature constant Gm current reference circuit which is also independent of voltage across the circuit which includes a circuit for applying a substantially identical voltage to a semiconductor diode as well as to a branch circuit comprising a polysilicon resistor of predetermined doping level in series with plural unidirectional current carrying devices connected in parallel, preferably in the form of a multi-electrode transistor. From eight to twelve such unidirectional current carrying devices are required in the preferred embodiment.

Abstract: In a preferred embodiment, a reversible DC power supply having an audible alarm, especially for use with electrochemical metallizing equipment. The audible alarm is electrically connected directly to the controls of the power supply so that when the power supply is placed in its "reverse" mode, the audible alarm will continuously sound, thus alerting the operator that the power supply is in that mode. In other embodiments, reversible electric tools, such as drills, may be provided with an audible alarm to indicate when they are in their reverse states.

Abstract: An improved stepping motor rotor assembly comprises a rotor having a shaft and a driving member such as a gear pinion, a centering washer disposed on the shaft and a recess with a short finished cylindrical wall coaxial with the shaft and annular abutment surface at the bottom of the recess, a rare earth permanent magnet having a rough center hole preferably drilled by laser beam defining an annular clearance with the shaft and having a finished outer cylindrical wall extending into the recess with a loose fit to center the magnet with respect to the rotor axis, and a holding washer forming an interference fit with the shaft and pressing the magnet axially against the abutment surface on the centering washer. The centering washer may be restrained in axial position by a light interference fit with the shaft or it may be held by contacting the driving member.

Abstract: Described is a novel power supply for generating a constant d.c. voltage from a variable a.c. voltage supply line. The power supply includes a plurality of switch circuits which monitor voltage levels on respective secondary windings of a power transformer and as voltage levels change, one of the plurality of switch circuits is selected to charge a capacitor which provides a range of d.c. voltages which are processed to provide the constant d.c. voltage.

Abstract: A cylindrical permanent magnet of from 4-48 poles containing, as major components, R (R is at least one rare earth element selected from Nd, Pr, Dy, Ho and Tb and may further contain at least one rare earth element selected from La, Ce, Sm, Gd, Er, Eu, Tm, Yb and Y), B and Fe, and having multipolar anisotropy at the surface without suffering from cracking. The ratios of inner and outer magnet diameters are established as functions of the number of poles. Bushings of ferromagnetic materials allow for reduced permanent magnet thicknesses.

Abstract: A high voltage DC power supply having a first series resistor at the output for limiting current in the event of a short-circuited output, a second series resistor for sensing the magnitude of output current, and a voltage divider circuit for providing a source of feedback voltage for use in voltage regulation is disclosed. The voltage divider circuit is coupled to the second series resistor so as to compensate the feedback voltage for a voltage drop across the first series resistor. The power supply also includes a pulse-width modulated control circuit, having dual clock signals, which is responsive to both the feedback voltage and a command voltage, and also includes voltage and current measuring circuits responsive to the feedback voltage and the voltage developed across the second series resistor respectively.

Abstract: A reluctance electric machine which comprises a stator with electric windings, a rotor including ferromagnetic material members, inserted into the stator and separted therefrom by an air gap, and members of non-ferromagnetic material inserted in the rotor in such a way that the cross section of the ferromagnetic material members of the rotor, at least near the air gap, is decreased by the insertion of the members of non-ferromagnetic material in such a way that the ratio between the ferromagnetic material cross section and the whole cross section available does not exceed 0.6, and the ratio between at least one linear dimension of the non-ferromagnetic material members, lying in a plane tangent to the air gap, and the thickness of the machine air gap, does not exceed 5. The electric machine is fed by an electronic circuit for vectorial control (in amplitude and phase) of the current feeding the electric windings of the stator.

Abstract: A voice coil-type linear motor comprising an cylindrical outer yoke made of a ferromagnetic material; a cylindrical center yoke made of a ferromagnetic material and magnetically coupled with the outer yoke; an integral, cylindrical magnet consisting essentially of an R-B-Fe alloy wherein R is at least one of rare earth metals such as Nd, Pr and Dy and having magnetic anisotropy in a radial direction, the cylindrical magnet being fixed to an inner surface of the outer yoke; a protective member made of a nonmagnetic and conductive material and fixed to a surface of the cylindrical magnet; and a movable coil means arranged in a magnetic gap between the center yoke and the cylindrical magnet.

Abstract: A stator of a rotary electric machine is supported in a housing structure and is secured therein against relative rotation or axial movement by angularly spaced fasteners. A circumferential passage in the stator communicates with a supply passage for liquid coolant. The temperature coefficients of expansion of the materials of the housing and the stator differ so that below a predetermined temperature those parts are an interference fit, and above that temperature channels are created between the fasteners, through which channels coolant can flow axially from the passage.

Abstract: A brushless servo motor for connection to a rotatable load without the need for initial adjustment and calibration of the external position servo loop. A plurality of keyways, keys, pins and projections ensure alignment of motor and position sensor rotors, motor and position sensor stators, motor and load shafts, and motor and load housings to eliminate the need for extensive adjustments. This also facilitates motor replacement without the need for readjustments.

Abstract: A filter for a switching power supply. The filter includes a common mode inductor with coil configurations allowing differential mode current from a dc source to pass through but attenuating common mode noise from the power supply so that the noise does not reach the dc source. The invention also includes the use of feed through capacitors at the switching power supply input terminals to provide further high-frequency noise attenuation.

Abstract: A reversible permanent split capacitor (PSC) motor and method of designing such a motor employs a parallelogram lamination silhouette and distributes the winding in the core of the motor stator assembly so that maximum flux density in the core is approximately equal in each direction of motor rotation. The motor is designed to achieve high repetition reversal rates. The reversal rate and the equal performance attained in each direction, makes the design particularly suitable for washing machine applications.

Abstract: A self-oscillating inverter uses saturable transformer means in its positive feedback circuit. The saturation flux density of the magnetic material used in this saturable transformer means determines the frequency of inverter oscillation. A permanent magnet is rotatably mounted proximate to the saturable transformer means and is used for adjustably affecting the saturation flux density of the magnetic material, thereby correspondingly to adjust the frequency of oscillation: the stronger the magnetic flux provided to the magnetic material from the permanent magnet, the smaller the saturation flux density and the higher the frequency of oscillation.

Abstract: Circuitry is provided to eliminate high frequency noise spikes in the output of a pulse width modulator and inverters employing pulse width modulators. This circuitry provides a precision noise spike elimination circuit based on a discovery that the switching of a MOSFET has two distinct regions: one in which only the drain current changes, and the other in which only the drain to source voltage changes. The precision noise spike elimination circuit includes a pair of back-to-back Zener diodes connected in parallel with the first current generator and direct feedback of the rate of change of voltage across the catch diode, thereby eliminating the effect of non-linear capacitance of the MOSFET in the feedback path. The back-to-back Zener diodes provide very precise control of the rate of change of the MOSFET current and catch-diode voltage. The more linear switching of the MOSFET due to the improved feedback results in a reduction in losses in the MOSFET for the same degree of noise reduction.

Abstract: A motor mounting means for a centrifugal coolant pump having its own cooling fans has a housing provided with a supporting surface therein for supporting a motor and flanges extending from one interior wall which index a motor and restrain the motor against rotational movement. A cap is secured to the housing by bolts extending through lugs located on the outside of the housing and into posts in the cap so that the size of the cooling fan is maximized. Index vanes within the cap position the cap and abut against a topside of the motor to secure the motor against the supporting surface.

Abstract: An electronic large current switch for a single power circuit has a DC-to-DC converter for low voltage transformation, the operation of which is controlled by a control switch or a periodic switching circuit and a switching transistor supplied with the low voltage output of the DC-to-DC converter as its base bias voltage and which controls the power supply to an electrical load circuit so as to be capable of minimzing the power loss of the switching transistor and making the product small and integrated.

Abstract: The invention comprises a universal stepping motor/gear train module for a wrist instrument having a frame plate, a bridge plate attached thereto and spaced therefrom, a stepping motor comprising rotor and stator disposed between said plates, a reduction gear train having gear members coupled to be driven by the rotor and having coaxial output members adapted to receive analog hands, an input/output circuit board disposed in said frame plate and having a pair of power supply terminals thereon, said frame plate defining a recess large enough to receive at least a portion of a button energy cell, and first and second spring contact connectors having ends adapted to contact the terminals of the energy cell and extending between the recess and the power supply terminals on the input/output circuit board, whereby power may either be supplied to said board directly from said power supply terminals or from said energy cell.

Abstract: A single stage power conditioner which produces an isolated DC output while drawing resistive input current from the utility has been described. A high frequency switch-mode technique was used which operates in continuous conduction mode to reduce electro-magnetic interference (EMI) generation and ripple losses.

Abstract: In the voltage controlled current source disclosed herein, temperature compensation is provided by offsetting base emitter voltage drops in a pair of bipolar transistors of complementary conductivity types. The control voltage is applied through a resistor to the emitter of a first transistor connected in common base mode. The base voltage of the first transistor is obtained from the emitter of a transistor of complementary conductivity type, the base of which is connected to a stable voltage source. The collector current of the first transistor is then applied to a current mirror to obtain an output current which is highly proportional to the control voltage.