Other

Synektron Corporation

Micropump, Inc.

C. R. Bard, Inc.

Mitsumi Electric Company Ltd.

Allen Fruit Co., Inc.

Joseph J Stupak, Jr

Kevin D O'Hara

Christophe J Sevrain

Kurt T Liebezeit

Glade Harold Howell

Eddie K Burnside

Robert N Golden

Bret Hamatake

Jon B Newman

Chad A Hadley

Robert M Pailthorp

Gulzar Ahmed

Erik Moe

James F Bausch

Randi Cleverly

Richard T Symer

Jack L Hoffman

Gregory L Branch

Randall B Elliott

Sarah L Creasy

Michael S Guthrie

Keith W Mayberry

Gregory H Chao

Todd R Hoffman

Rian M Callahan

Michael Stupak

Sarah L Montgomery

A method of attaching a magnetic element to a needle assembly. The needle assembly can include a cannula extending along a longitudinal axis. The method can include placing the magnetic element in a magnetic field such that a magnetic axis of the magnetic element substantially aligns with the magnetic field. The method can further include securing the magnetic element to a portion of the needle assembly while the magnetic element is substantially aligned with the magnetic field such that the magnetic axis of the magnetic element is secured in a desired predetermined orientation.

Needle assembly including an aligned magnetic element

A method and system for driving a magnetizing fixture. A driving circuit produces in the conductor of a magnetizing fixture a first current whose magnitude increases substantially linearly with time, then produces a substantially constant current in the same direction, then produces a current in the same direction whose magnitude decreases substantially linearly with time, thereby forming a substantially trapezoidal magnetization current waveform having symmetrical sides. The circuit comprises a first energy storage device for supplying electrical energy to the magnetizing fixture, a second energy storage device for receiving electrical energy from the magnetizing fixture, and a commutator interconnecting the first energy storage device, the second energy storage device and the magnetizing fixture for stopping the flow of electrical energy into the magnetizing fixture from the first energy storage device and starting the flow of energy from the magnetizing fixture into the second energy storage device.

Method and system for driving a magnetizing fixture

A magnetic flux measuring device includes a coil of conductive material for sensing magnetic flux and producing a voltage in the presence of a changing magnetic field. An analog to digital converter is coupled to an output of the sensing coil for sampling the voltage produced by the magnetic flux sensing coil and for converting that voltage to digital data. A digital integrating device determines the total magnetic flux sensed by the coil over an event time interval by integrating the digital data over that same time interval.

Total magnetic flux measuring device

A coil for magnetizing an article. The coil includes a cooling coil component and an electric coil component. An elongate electric coil component is placed with its center along a bobbin, wherein one end is wound in one direction around the bobbin and the other end in the other direction. The cooling coil component includes a disk-like member in which a passage is formed for carrying a fluid coolant. The disk-like member is 'C' shaped to substantially prevent the flow of eddy currents. Electric coil components disposed at the ends of the coil are provided with a greater number of windings to make the magnetic field in the coil more uniform.

Coil and method for magnetizing an article

A magnetizing device for generating a high current magnetizing pulse includes a plurality of charge storage devices and a source of current connected by selector switches for charging selected ones of the charge storage devices to a predetermined voltage level. When the selected charge storage devices are charged the selector switches are opened and the selected charge storage devices are discharged through diode circuits coupled to a common SCR. In this way the current pulse does not flow through the selector switches. A peak current meter using a current transformer provides a display of the peak current of the magnetizing pulse.

Magnetizing device having variable charge storage network and voltage

An elongate vibratory conveyor for moving products is reciprocated by driving a motor with a cyclical nonuniform motion by supplying power nonuniformly to the motor. The conveyor is reciprocated in opposite lengthwise directions, without any substantial movement of the conveyor normal to the lengthwise direction. Motor control circuitry variably drives the motor automatically in response to feedback from a sensor which senses a motion related to the conveyor motion. The feedback signal is compared to a selected one of a set of predetermined different motion patterns, and the motor is driven by supplying power nonuniformly thereto in accordance with the selected motion pattern. The conveyor system readily enables instantaneous reversibility of the product flow at the same average velocity, and instantaneous variable control for modifying the motion of the conveyor to obtain either different desired average product velocities or the same average product velocity at different conveyor inclinations or reciprocating frequencies, all irrespective of changes in conveyor loading or resistance to slip of the products conveyed. Separate motors driving either the same conveyor or separate conveyors are driven with cyclical nonuniform motions in synchronization by synchronizing their respective power supplies.

Variably-controlled vibratory conveyor

A small form factor disk drive having an extremely thin, high-energy product annular magnet within the spindle motor. The magnet includes twelve alternating poles disposed about the periphery and canted from the top edge to the bottom at a slight skew angle. The high-energy product magnet generates a high starting torque which obviates the use of low viscosity lithium bearing greases. A stator disposed concentrically within the magnet has three continuous coils, each coil wound around three spokes of the stator at 120 degree intervals, for a total of nine stator slots. The rotating spindle, bearings and stationary base are constructed of materials having similar coefficients of thermal expansion to reduce stresses on the bearings during periods of temperature elevation. An annular aluminum disk support sole bonds to a ledge on the spindle hub to facilitate machining and provide material compatibility. The disk drive includes various features for reducing the amount of contamination on the disk surface. A double groove bonding configuration eliminates adhesive runout and ensures a consistent bond strength.

Disk drive spindle motor

A pump assembly includes a pump head that is coupled to a permanent magnet rotor. The rotor is enclosed in a cavity defined by a fluid-tight cup that has an open first end and a closed second end. This cavity is in fluid connection with the pump head through its open first end. Outside the cup enclosure are disposed a plurality of electrical stator windings. A housing encloses all of the foregoing elements, and may also enclose a circuit board that includes circuitry for driving the stator windings. The pump assembly thereby provided is compact, efficient, and reliable.

Integral electronically commutated drive system

Pump assembly with integral electronically commutated drive system

A tachometer or accelerometer features a nonmagnetic, electrically-conductive, moving member whose velocity or rate of change of velocity is to be measured. A magnetic field is generated in a direction generally perpendicular to the direction of motion, creating eddy currents in the moving member which, in turn, create an eddy current magnetic field. The flux density of the eddy current field is measured by a Hall effect sensor to produce a signal representative of velocity or, alternatively, the rate of change of flux density of the eddy current field is measured by a coil producing a signal representative of the rate of change of velocity. A separate magnetic circuit for the Hall effect sensor or coil sensor, as the case may be, is provided so as to maximize the strength of the eddy current field by concentrating the sensed eddy current flux and thereby maximizing the device's sensitivity and accuracy while minimizing its susceptibility to error through interference.

Magnetic tachometer or accelerometer having highly permeable eddy

A controlled force variable reluctance actuator. A variable reluctance actuator having a moving element operated by a solenoid is provided in which the current in the solenoid is controlled by a signal representative of the flux density in the magnetic circuit of the actuator. The signal is produced by a Hall effect device placed in the magnetic circuit. Preferably, the Hall effect device controls the current in the solenoid by controlling its duty cycle; however, continuous control of the current may also be employed. Alternative embodiments are provided for a constant force actuator, an actuator whose force-displacement characteristic is altered, and an actuator in which the force may be selectively controlled. An embodiment is also provided for selectively controlling the position of the moving element based upon measured electric and magnetic parameters of the actuator.

Method for sensing and controlling the position of a variable reluctance

Variable reluctance actuator having position sensing and control

A variable reluctance actuator, of either the linear or rotary type, having a moving element operated by a solenoid, is controlled by a Hall effect sensor signal representative of flux density in the magnetic circuit of the actuator. The actuator may be operated in either a constant-force control mode, or a position-sensing or control mode. Substantially constant force, independent of position of the actuator's movable element, is obtained by varying, rather than stabilizing, the sensed magnetic field during movement. Position sensing, independent of actuator force, is obtained by variably controlling the magnitude of the excitation current of the Hall effect sensor in response to the magnitude of the coil current and Hall sensor output.

Variable reluctance actuators having improved constant force control and

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Portland, OR, United States of America

Joseph J Stupak, Jr