Abstract: A drive method for a brushless motor and a drive control apparatus therefor, in which control parameters are calculated by revolution number control means or motor current control means in accordance with the deviation between a target value and an actual value, a manipulated variable is computed by conduction phase control means on the basis of the calculated control parameters, an advance angle magnitude is computed from the relationship between a manipulated variable and an advance angle magnitude as designed and created beforehand, on the basis of the computed manipulated variable, and the value of a conduction phase angle of a drive circuit as designed on the basis of a rotation position signal or a motor current signal is corrected using the information of the computed advance angle magnitude.

Abstract: A power closure system with anti-pinch having a closure, a motor operatively connected to the closure, a sensor operatively producing signals indicative of motor speed, an anti-pinch activator coupled to the sensor and the motor, the anti-pinch activator including a predetermined trigger value; a measured value; a stored value; a comparator for comparing the measured value with the stored value and initiating a pinch response when the difference between the measured value and the stored value is greater than the trigger value; and a predetermined modifying calculation for changing the stored value when the measured value indicates a motor speed less than the motor speed indicated by the stored value.

Abstract: A motor power supply including a DC supply part having a pair of supply terminals; an inverter having a pair of connection terminals respectively connected to the supply terminals thereof to receive DC power therefrom and to supply AC power to a motor, a breaking resistor and a control switching element disposed in parallel in an additional line connecting the pair of connection terminals to each other, a control switching element disposed with the breaking resistor in the additional line, a breaking switch disposed to one of the connection terminals and switched to either a normal position or a breaking position connecting the one connection terminal to a corresponding supply part or to the additional line, a speed detector detecting a motor speed and a control part controlling the breaking switch to switch to the breaking position and controlling the control switching element so that an on-off interval of the control switching element is controllable depending on the detected speed.

Abstract: A motor control apparatus supplying braking power to brake a motor comprises a braking power providing unit to receive input power having an input power voltage lower than a braking power voltage and to boost the input power voltage up to the braking power voltage to brake the motor; a switching unit closing to allow the braking power providing unit to store the input power and opening to allow the braking power providing unit to output the braking power by boosting the input power voltage and a stored power voltage up to the braking power voltage; and a controller to control the switching unit to close and to open. With this configuration, a motor control apparatus is provided, in which an additional braking power supply supplying braking power to brake a motor is not needed, thereby decreasing a production cost and a size of a product.

Abstract: A method for greatly reducing magnetic sound of an alternating current rotating machine compared with the past comprising superimposing an n?1-th order frequency in inverse turn on a multi-phase alternating current with reference to a basic frequency component of the multi-phase alternating current supplied to an armature of the alternating current rotating machine of multiple phases so as to reduce the n-th order harmonic components of the basic frequency component among radial direction magnetic vibrating forces generated in the radial direction in a core of the alternating current rotating machine.

Abstract: Disclosed are systems and methods for operating a barrier. In one embodiment, a door operator can be opened or closed by triggering either an internal device (e.g., wall button) or an external device. In one embodiment, if an obstacle is detected when the door is opening or closing, the door will either stop or swing in the reverse direction. In yet a further embodiment, the door operator is implemented using an alternating current (AC) synchronous motor.

Abstract: A method and apparatus for compensating for the asymmetrical phases of a spindle motor in a disc drive are provided. With the apparatus and method, compensation values are learned by sampling speed data during a period of operation of the disc drive where the speed is stable and only one control operation is performed per revolution of the disc. The sampled speed data is used to generate the compensation values for each of the phases of the spindle motor. The compensation values are stored in a compensation mechanism which is used by the spindle motor speed controller to provide compensation for the asymmetrical phases of the spindle motor. During Normal operation, the actual speed output of the spindle motor is measured and is subtracted from a reference speed to generate a difference speed value. Based on the corresponding electrical phase, the correct compensation value is fetched and is subtracted from the difference speed value to obtain a compensated difference speed value.

Abstract: In a holding arrangement (101) for a medical-optical instrument (103), an electric motor is provided in a rotational joint (111, 119) to compensate a load torque occurring in this rotational joint. This electric motor is supplied with current in correspondence to a detected position of the rotational joint (111, 119). A current control curve required for this purpose is stored in a memory. This current control curve can be determined in that the rotational joints are deflected with the electric motor into predetermined positions and the current demand needed therefor is detected. The holding arrangement (101) has a unit for actively damping vibration including a vibration damping control loop. This vibration damping control loop outputs a superposition motor current to the electric motor as an actuating quantity in order to move the rotational joint (111, 119) with the electric motor so that a detected vibration of the holding arrangement (101) is countered.

Abstract: A diagnostic system is disclosed for analyzing a limited rotation motor system. The diagnostic system includes a first transform unit, a second transform unit, a closed loop frequency response unit, and a diagnostic system. The first transform unit is for receiving a first digital signal that is representative of a motor control signal, and is for providing a motor control frequency domain signal that is representative of a frequency domain representation of the motor control signal. The second transform unit is for receiving a second digital signal that is representative of a position detection signal, and is for providing a position detection frequency domain signal that is representative of a frequency domain representation of the position detection signal. The closed loop frequency response unit is for identifying a representation of the frequency response of the limited rotation motor responsive to the position detection frequency domain signal and the motor control frequency domain signals.

Abstract: An automaton configured to perform a task comprises a communication interface to communicate positional information with one or more anchor points provided within a given environment. The positional information enables generation of mapping information of the given environment. A motor provides the automation with mobility. A memory stores the mapping information. A controller controls the motor to enable the automaton to perform the task in the given environment using a first task route that has been generated using the mapping information.

Abstract: Latch control methods and systems are disclosed, including a latch that receives power from a motor associated with a latch. A sensor can be provided for monitoring the current consumption of the motor. A microcontroller can control the latch and/or the motor, based on the current consumption data received from the sensor concerning the current consumption of the motor. Monitoring of the current waveform of the motor therefore provides speed and direction feedback data for control of the latch. Additionally, a microprocessor can process instructions for controlling the interaction of the motor, the latch, the sensor and/or the microcontroller. Such a current monitoring control system is made possible by variation in current consumption of the motor during rotation as a result of commutation, which can be interrogated by measuring the voltage drop across the motor or a shunt resistor, or through the use of other current sensors, such as, for example, a Hall-effect type current sensor.

Abstract: A stepper motor driving apparatus, includes a stepper motor; a driven member interlocked with a rotation of a rotor of the stepper motor, a stopper stopping the driven member in a zero position, a controller controlling the excitation state of an excitation coil of the stepper motor, an induced voltage waveform detector detecting an induced voltage waveform generated on the basis of change of magnetic flux in accordance with the rotation of the rotor, and a zero position detector detecting whether the driven member is stopped in the zero position. The zero position detector includes a comparator which compares a time T2 in which each induced voltage waveform exceeds a predetermined threshold value with a predetermined contact determining reference time Tref, and a determinant which determines whether the driven member is stopped in the zero position by the stopper based on a result of the comparison by the comparator.

Abstract: The present invention provides an electro-mechanical energy exchange system with a variable speed synchronous reluctance motor-generator having an all-metal rotor. A bi-directional AC-to-DC electric power converter interconnects the motor-generator with a DC bus. First and second hybrid controllers provide current regulation for the motor-generator and voltage regulation for the DC bus. Use of both feedback and feedforward control elements provides a controller particularly suited for operating high speed devices.

Abstract: In the control of a synchronous motor having a permanent magnet, an alternating current power supply voltage that is input to a power amplifier or a direct current link voltage of which input voltage is rectified is measured. A reactive current (a d-axis current) or a current control phase advance is changed, according to this power supply voltage. With this arrangement, reactive current control or current phase control can be carried out directly according to a change in the input power supply voltage. A motor control device includes a voltage measuring unit that measures a voltage supplied to a driving amplifier, and a current control unit that controls a current passed to a synchronous motor based on the measured voltage. The voltage measuring unit measures a voltage supplied to the amplifier. The current control unit controls a current that is passed to the synchronous motor, according to the measured voltage.

Abstract: A card type device serving as a supplementary power supply device, and a host using the same. The card type device may include a battery provided in a frame to serve as a supplementary power supply to the host, a connector to connect to the host for an interfacing of power and data to and/or from the host, a battery charging/discharging circuit to charge the battery with an input power supplied via the connector, and to output the power of the battery via the connector. A power input/output controller provides the host with information of attributes of the battery during a connection to the host, with the power input/output controller to control the battery charging/discharging circuit so that the power of the battery is supplied to the host when a request for power supply is transmitted from the host. The power input/output controller controls the battery charging/discharging circuit so that the battery is charged with the input power when the battery is completely discharged.

Abstract: An AC plug of a battery charger is arranged so as to be enclosed into a casing of the battery charger or projected therefrom when it is laterally rotated. The AC plug has two conductive blades and an edge surface for projecting them at an almost right angle. A first surface and a first rotary shaft are provided for a first side surface. A second surface and a second rotary shaft are provided for a second side surface opposite to the first side surface. A first contact portion electrically connected to one conductive blade is projected from the first rotary shaft. A second contact portion electrically connected to the other conductive blade is projected from the second rotary shaft. Conductive spring terminals which are elastically come into contact with the front edges of the first and second contact portions are provided for a board in the casing. By reducing a rotational radius of each contact portion, a small battery charger is provided.

Abstract: In accordance with the teachings described herein, systems and methods are provided for charging a rechargeable power source in a mobile device through a USB port. A power converter may be used to receive an input voltage from an external power source and generate a charger output having a regulated voltage. A signal generator may be used to generate a charger configuration signal having pre-selected waveform characteristics that are selected to identify operating characteristics of the charging apparatus. A USB connector may be used for coupling the charger output and charger configuration signal to the USB port on the mobile device. The USB connector may include a voltage bus (Vbus) contact coupled to the charger output, a positive data (D+) contact coupled to the charger configuration signal, and a negative data (D?) contact coupled to the charger configuration signal.

Abstract: A rapid charging circuit for charging a power module is disclosed. The power module includes one or more ultracapacitors. The power module is charged using an energy source connected to the power module. The charging circuit includes a control circuit adapted to maintain a constant power level at the power module during charging as the voltage level across the power module increases. The control circuit includes a pulse-width modulator and an inductor connected in series with the power module. The pulse-width modulator can control a charge level of the inductor. The charge level may correspond to a current level which is in accordance with a desired power level at the power module and an instantaneous voltage level across the power module. The inductor may be adapted to limit a current level through the power module to a predetermined peak level.

Abstract: A generator system has two modes of operation, such as 120 VAC and 240/120 VAC. The generator system has a permanent magnet generator with two independent sets of windings that each generate a three phase AC voltage. One three phase AC voltage is coupled to a first cycloconverter and the second three phase AC voltage is coupled to a second cycloconverter. Live outputs of each cycloconverter are coupled to each other through a switch, such as a relay, and netural outputs of each cycloconverter are coupled to ground. A controller controls the cycloconverters to provide the modes of operation. In the 120 VAC mode, the switch across the live outputs of the first and second cycloconverters is closed, shorting the live outputs of the first and second cycloconverters together so that the live outputs are in parallel and the controller operates the first and second cycloconverters so their output voltages are in phase with each other.

Abstract: A variable frequency power system with a power source having a rotating output and a speed control to regulate rotational speed of the rotating output. A generator coupled to and driven by the rotating output of the power source, whereby the speed control of the power source directly controls output power frequency of the generator due to control of rotational frequency of the rotating output. A voltage regulator connected between the generator and the motor regulates output voltage from the generator to the electrical motor load. A system controller controls output power frequency of the generator. The system controller interfaces with the speed control of the power source and configured to monitor generator output and operational conditions of the electrical motor load. The system controller adjusts the speed control based on generator output and operational conditions of the electrical motor load.

Abstract: An apparatus for controlling an on-vehicle generator is provided. The apparatus comprises a switching element, current detecting unit, setting unit and driving unit. The switching unit turns on/off an exciting current to an exciting winding of the generator, the switching element being driven responsively to a driving signal having an adjustable duty ratio. The setting unit sets the duty ratio based on (i) a difference between an output voltage of the generator and a target voltage value and (ii) a condition in which an electric load is disconnected from the generator, wherein the duty ratio is allowed to lower than a minimum value of the duty ratio depending on a generated state of the generator. The minimum value allows the exciting current to flow at a lower limit detectable by the current detecting unit, The driving unit drives the switching element based on the driving signal.

Abstract: A compensation circuit in a monolithic switching regulator controller being incorporated in a closed loop feedback system of a switching regulator includes an amplifier configured in a unity gain feedback configuration with a first resistor and including a non-inverting input terminal receiving the feedback voltage and an inverting input terminal coupled to a first terminal of the switching regulator controller. The compensation circuit further includes a first capacitor and a third resistor connected in series between an input terminal and an output terminal of an error amplifier of the switching regulator controller. The first capacitor and the third resistor introduce a first zero in the closed loop feedback system. When a second capacitor is coupled to the first terminal of the switching regulator controller, a second zero is introduced in the closed loop feedback system. The second capacitor is an off-chip capacitor formed external to the monolithic switching regulator controller.

Abstract: A dual output voltage regulator circuit is disclosed. The output voltage regulator has a first FET and a second FET. A current source responsive to the regulated output voltage provides a current drive to the gate of the first FET in a first mode of operation and to the gate of the second FET in a second mode of operation. Further, the circuit employs switches for switchably selecting between the first mode of operation and the second mode of operation.

Abstract: A fully differential class D amplifier includes a pulse width modulator and a power stage. The pulse width modulator is arranged to employ a differential output signal provided from the power stage as a feedback signal. The pulse width modulator includes a transimpedance amplifier that is arranged to generate a triangle wave from the input signal and the feedback signal. The transimpedance amplifier is arranged to generate the triangle wave such that the triangle wave that has approximately a 50% duty cycle when no input signal is applied. Additionally, the input signal adjusts the frequency of the triangle wave such that the triangle wave is a spread spectrum signal. The triangle wave is compared to a threshold signal to provide a pulse width modulated signal.

Abstract: A system and method control an output voltage across a load using current mode control to control current through an output filter connected to the load. The output voltage across the load is compared with a reference voltage to generate a reference current signal indicative of a desired average current through the load. A control signal is generated to indicate when an output current is greater than the desired output current. The output filter is alternately coupled to a first supply rail and to a second supply rail in response to the control signal to generate an average current through the load.

Abstract: A DC to DC converter including a zigzag transformer. The transformer operates at high frequency with integrated magnetics and does not provide isolation. The multiphase converter has gate inputs with PWM signals appropriately phase-shifted depending on the number of phases to make balanced phase voltages across the transformer windings. The switching frequency of the converter is relatively low but fast transient response can be achieved by adding an integrated zigzag transformer.

Abstract: A hard saturation mode of operation can be avoided in an LDO regulator by providing an additional feedback control loop. The additional control loop cooperates with the LDO regulator's amplifier stage and output stage to maintain at least a minimum desired voltage drop across the output stage from the power supply to the load.

Abstract: The invention relates to a control device for operating a load circuit provided with an inductive load, comprising a control stage producing a pulse-width modulated control signal with measuring disconnection intervals provided in between said control signal, a power stage feeding the load circuit and comprising an electronic switch controlled by the pulse-width modulated control signal and a freewheeling element which is connected in parallel to said load circuit. In order to improve upon said device so that it is possible to determine in a simple manner the amount of current flowing into the load circuit, a current detection unit for determining the amount of current flowing into the load circuit prior to the measuring disconnection interval detects the duration of freewheeling time and calculates the value of said current therefrom.

Abstract: A DC-to-DC voltage converter having an active charge/discharge circuit enabling the definition of any output voltage within its operating range has been achieved. A comparator compares the output voltage of a voltage converter with a defined reference voltage. This reference voltage can be easily modified within its operating range. In case the output voltage of the voltage converter is higher than said reference voltage a “reservoir” capacitor at the output of said voltage is discharged via an active charge/discharge circuit until the output voltage equals said reference voltage. Said active charge/discharge circuit is activated via a latch by said comparator. The invention is applicable for any type of DC-to-DC converters, such as e.g. charge pumps, buck converters and boost converters.

Abstract: A semiconductor integrated circuit for controlling power supply which has a function of preventing a reverse current flowing in a coil under a light load condition and ensures good response of output voltage to load variation. In a synchronous rectification switching regulator having a reverse current detection circuit which can detect a reverse current flowing in an inductor (coil) and a reverse current prevention function, when a prescribed time has elapsed after detection of a reverse current based on a detection signal from the reverse current detection circuit or after the number of times of reverse current detection has reached a prescribed value, the reverse current prevention function is activated to turn Off a synchronous rectification switching device.

Abstract: The object of the invention is to compensate an effect of a voltage drop emerging in output voltage by the equivalent series resistance of a power output filter in a power-supply device. To achieve the object, a power-supply device wherein the power output filter that passes output power and first and second filters provided separately from the power output filter are provided, the first filter provided separately and one input terminal of an error amplifier are connected, new reference voltage acquired by adding differential voltage between the output of the second filter provided separately and the output of the power output filter to reference voltage is input to the other input terminal of the error amplifier and an output signal is fed back to the error amplifier is provided. According to the power-supply device, a voltage drop by equivalent series resistance emerging the output voltage of the power-supply device can be compensated.

Abstract: A bandgap reference includes a current source providing a current that is proportional to the sum of a first voltage having a positive-to-absolute-temperature (PTAT) temperature dependency and a second voltage having a complementary-to-absolute-temperature (CTAT) dependency. The bandgap reference further includes a variable resistor comprising a fixed resistor that may be selectively combined with one or more of a plurality of selectable resistors, wherein the first voltage is inversely proportional to the resistance of the variable resistor.

Abstract: Method and system for periodically measuring the junction temperature of a semiconductor device. The junction is excited by at least two sequential predetermined currents of different magnitudes. The voltage response of the junction to the at least two currents is measured and the temperature of the junction is calculated, while substantially canceling ohmic effects, by using the voltage response and a correction factor. Whenever desired, the junction is excited by a set of at least four sequential different currents having known ratios. The voltage response to the set is measured and the correction factor is calculated by using each voltage response to the set.

Abstract: A device for compensating for heat generation in a modular IC test handler is provided which includes at least one supporting member positioned adjacent to a press unit of the handler, and having a cooling fluid flow passage formed therein for flow of cooling fluid, and a plurality of cooling fluid spraying units for spraying the cooling fluid supplied through the cooling fluid flow passage toward faces of modular ICs in an oblique direction from a position between adjacent push bars of the press unit, thereby spraying cooling fluid directly onto ICs attached to a surface of modular ICs during testing and enhancing an efficiency of heat compensation.

Abstract: The invention provides tester load board shields (10, 40) for attachment to tester load boards. The shields (10, 40) of the invention protect from physical damage and electromagnetic interference. A preferred embodiment of a tester load board shield (10) of the invention is disclosed in which a disc (12) and outer rim (14) of conductive metal such as aluminum or aluminum alloy are configured to accept a tester load board. The tester load board shield (10) has holes (18) to align with a selected tester load board for attachment of the shield (10) thereto. Stanchions (22) are provided to facilitate attachment of the Loadboard with shield (10) to automatic test equipment known in the arts while a tester load board, also familiar in the arts, is fastened to the shield (10). Another embodiment of a tester load board shield (40) is disclosed in the shape of annulus (42) configured to contain a tester load board within an outer rim (44), planar surface (46), and inner rim (50).

Abstract: A device (16) for sensing the axial position, in relation to the other component, of one of two components mobile relative to each other, in particular a piston (12) in relation to a cylinder housing (14), which device has a magnetic signal element (18) arranged on the one component and a magnetic-flux-sensitive sensor (20, 20?) arranged on the other component, of which the axial relative position of the signal element to the sensor can be detected. One flux guide element (22, 22?) is allocated to the sensor stationary in relation to the sensor, which extends on the other component at least over the area to be detected of the axial relative positions of the signal element to the sensor and comprises a plate section of a magnetizable material, wherein the sensor is arranged at one longitudinal end of the flux guide element outside the area to be detected of axial relative positions.

Abstract: A device for angle measurement, having at least one transducer wheel and at least one sensor, including at least one sensor element and cooperating with the transducer wheel, in which by means of the cooperation of the transducer wheel and the sensor, a pair, which can be associated with an angle to be measured, comprising one sine-wave signal and one cosine-wave signal can be obtained, in which at least two sensors are provided, whose sine-wave signals and cosine-wave signals, for obtaining an averaged sine-wave signal and averaged cosine-wave signal, and/or after the formation of an arc tangent signal from the respective averaged or unaveraged sine-wave signals or cosine-wave signals, can be put computationally into relation with one another by means of an evaluation device in order to obtain an averaged arc tangent signal.

Abstract: In a method for the detection of local displacements and rotations, a sum signal and additionally a difference signal are formed from two separately generated signals of two transducer elements (W1, W2), which are spaced from each other, and subsequently the formed sum signal and the formed difference signal are OR-operated. A device for doubling the local frequency of moving incremental scales comprises an encoder (1a, 1b, 1c), a magnetically sensitive transducer (9, 13), and a signal conditioning stage (6a, 6b) electrically connected thereto. The transducer comprises at least two sensorially active functional groups synchronously using sensorially active groups or sub-groups (W1, W2) which are locally offset in relation to each other by a local phase ? in order to scan the moving scale, and the functional groups comprise means enabling at least two independent partial signals S1=V*sin(?t) and S2=?V*sin(?t)+?) to be produced.

Abstract: In a rotation detecting device attached to an end face of a hub bearing for an automobile, a sensor body (a resin molded member) having a holder member and a connector member is integrally formed in a single resin molding process. The rotation detecting device shortens the distance between a detection surface of a molded IC and a rotor. The holder member is defined by a recess with a bottom portion and two sidewalls. The molded IC has a detection surface, a back surface opposite to the detection surface, and side surfaces. The molded IC is fixed on the holder member and exposes the detection surface. The back surface of the molded IC is opposed to the bottom portion of the holder member. The side surfaces correspond to portions to be press-fitted, and the sidewalls of the holder member correspond to portions to press-fit.

Abstract: A rotation detector designed to prevent line disconnection from being caused by an abrupt thermal change, comprising cores (10, 30) arranged inside a cylindrical housing (1), pins (15a, 15b; 35a, 35b, 35c, 35d) attached to the cores (10, 30) and connected to coils (13, 23) of the cores (10, 30), protruding from a notch (1a) of the housing (1), and a connection base (50) electrically connected to the outside via a lead wire (59) and fixed to the pins (15a, 15b; 35a, 35b, 35c, 35d).

Abstract: A position-of-magnetic-pole detecting device includes first and second units for inferring a position of a magnetic pole. The first unit applies a current command while changing an excitation phase, infers a domain, where the position of a magnetic pole lies and which has the width thereof determined with a range of electrical angles, from the direction of rotation in which a motor rotates, and the excitation phase, and reduces the domain so as to infer the position of a magnetic pole. The second unit infers the position of a magnetic pole from a fed-back current returned responsively to a voltage command applied with the excitation phase sequentially changed. Thereafter, a voltage high enough to cause magnetic saturation is applied in order to determine the orientation of a magnetic pole, whereby the position of a magnetic pole is inferred. Although the first unit is selected, if the motor does not move due to friction or the like, the second unit is used to infer the position of a magnetic pole.

Abstract: A passive blade detection sensor exploits the electrically conductive trait of typical turbo machinery components such as fan, compressor and turbine blades. A permanent magnet is placed strategically adjacent to a wire coil to generate a single pulse/antipulse signal when a blade passes in front of the sensor. The electrically conductive blade allows eddy currents to flow briefly as it passes through the magnetic field, the local reluctance is momentarily increased, and the magnetic field is momentarily changed. The coil is sensitive only to the portion of change through its cross section, so that a simple voltage pulse, useful for precise timing of blade passage, is produced. The present disclosure also describes an open-loop and closed-loop active cooling system. The cooling system includes a casing, having internal sensing components and an inlet, coupled to one end of the casing.

Abstract: A ball and socket joint (1) is provided with a pivoting angle sensor (9) for detecting the relative angular position of the joint housing (4) and the ball pivot (3). The pivoting angle ? of the joint ball (2) is detected by a measuring means comprising a magnet (8) and a magnetic field sensor (9). The position and the size of the magnet (8) as well as the position and the size of the recess of the joint ball (2) are selected for each type of ball and socket joint from one series such that when the particular nominal pivoting angle ?m of the ball and socket joint (1) is reached, the angle ? of the magnetic field lines (12) passing through the magnetic field sensor (9) approximately equals a constant ?m, which applies to the entire series.

Abstract: A magnetic material detecting device which detects a magnetic material by applying a magnetic field to the magnetic material and detecting a magnetic field generated from the magnetic material by the applied magnetic field, and which includes a magnetizing coil which emits a magnetic field that excites the magnetic material, and a dummy coil which generates a magnetic field that excites the magnetic material by electromagnetic induction caused by the magnetic field emitted from the magnetizing coil, in which the dummy coil is disposed at a position where the electromagnetic induction is generated.

Abstract: A thin film magnetic sensor comprises a pair of thin film yokes each formed of a soft magnetic material, the thin film yokes being arranged to face each other with a gap interposed therebetween; a GMR film electrically connected to the pair of the thin film yokes and having an electrical resistivity higher than that of the soft magnetic material; and an insulating substrate supporting the thin film yokes and the GMR film and formed of an insulating nonmagnetic material. A gap column of a multilayer structure including a layer formed of an insulating nonmagnetic material and a layer of the GMR film is arranged within the gap, and the thickness of the GMR film is uniform over the gap length.

Abstract: A system and method for probing a specimen to determine one or more components by utilizing a first signal to excite the specimen at a nuclear quadrupole resonant frequency and observing changes in a specimen property. One exemplary property may be dielectric constant. Another exemplary property may be magnetic permeability. In one embodiment, the first signal is unmodulated and a second signal is observed for the presence of modulation at the frequency of the first signal. Alternatively, the first signal may be modulated and the second signal may be observed for the presence of the modulation. A system is disclosed wherein the specimen is excited using the first frequency and a radar at the second frequency is used to observe changes in radar reflectivity of the specimen due to the excitation.

Abstract: In diffusion weighted imaging, motion monitoring navigation echoes are measured at every measurement of data after applying an RF excitation pulse, and one of them is set as a reference navigation echo. The reference navigation echo and other navigation echoes are one-dimensionally Fourier-transformed, a linear phase gradient thereof is calculated from those data, a linear phase gradient of the reference navigation echo is compared with those of other navigation echoes, and it is judged whether a difference therebetween is within an acceptable value or not. An echo signal corresponding to a navigation echo having the above difference being larger than the acceptable value is judged that correction based on the navigated motion correction is not applicable therein, and the image is produced by using an echo signal measured along with a navigation echo having the difference being the acceptable value or less.

Abstract: An MRI method comprising preparing at least two pulse sequence databases (PSDs) assumed to have the same echo time (TE) and different repetition times (TR), driving a magnet system of an MRI apparatus in accordance with the two PSDs and collecting MR signals at that time, generating an MR image from MR signals collected in accordance with the PSDs, and weighting a tissue having a specific T1 value with reference to an image corresponding to a found difference between two MR images.

Abstract: An actively shielded superconducting magnet coil system (1) for generating a magnetic field in a working volume (6), which is rotationally symmetric about a z-axis, comprising a radially inner main field winding (5) and a radially outer shielding winding (7), and an electrically highly conductive shielding cylinder (radially inner shielding cylinder) (8a/8b) which is disposed radially inside the main field winding (5) or between main field winding (5) and the shielding winding (7) is characterized in that at least one further electrically highly conductive shielding cylinder (9) is disposed radially outside the shielding winding (7). The inventive magnet coil system prevents generation of a fringe field flash in the outer region of the magnet coil system in case of a quench.

Abstract: An improved axial gas bearing for a gas-driven NMR MAS sample rotor is disclosed that utilizes inward flow with a low rotational component over a rotor conical end. A conical flow region is formed between the rotor conical end and a conical stator bearing surface such that the included angle defining the stator surface is not less than the included angle defining the rotor conical end. Gas is injected radially inward with a significant axial rearward component from a number of small holes at high velocity from the periphery into the conical flow region. Compared to the radial velocity components, the tangential flow components of the injected gas are small and preferably opposed to the direction of the rotor rotation.