Abstract: In order to provide a driving device that is capable of eliminating sticking of a movable member due to nonuse, the driving device includes a drive shaft that reciprocates in axial directions with expansion and contraction of an electromechanical transducer element, a movable member that frictionally engages with the drive shaft, and a drive circuit that inputs drive voltage into the electromechanical transducer element, the drive circuit outputting drive operation pattern voltage having a frequency (fd1?) lower than a resonance frequency (fr) of the electromechanical transducer element and lower than a frequency (fd1) that maximizes moving velocity of the movable member and sticking elimination pattern voltage having a frequency lower than the frequency (fd1?) of the drive operation pattern voltage and in vicinity of a frequency (fd2) that maximizes thrust acting on the movable member.

Abstract: An electric vehicle is described herein which includes a microprocessor based interface module which is used to control electric motors coupled to drive wheels. The interface module is configured to include a backup communications link to allow an operator to control the vehicle in situations where control information is unavailable over a primary communications network.

Abstract: The present invention pertains to vibration devices that do not require a rotating mass. In accordance with aspects of the invention, a coil causes a plunger to move linearly. A spring device is coupled to one end of the plunger. Activation of the coil causes the plunger to move in a first direction relative to a body and coil deactivation enables the spring device to move the plunger in an opposite direction relative to the body. Activating the coil at a predetermined frequency causes vibration of the plunger. Vibratory forces are transferred via the spring device and coil onto the body at predetermined locations. Opposing spring devices may be affixed to either end of the plunger. Spring devices may be linear or non-linear. Such spring devices may be used in conjunction with magnetic spring devices. A controller and a driver circuit may be used to control system operation.

Abstract: A mechanical device capable of switching between two states is described. The device may include a micromechanical resonator with two distinct states in the hysteretic nonlinear regime. The devices can be used as a low-power, high-speed mechanical switch integrated on-chip with silicon circuitry.

Abstract: The invention relates to an apparatus and to a method for controlling or regulating the deflection of micromechanically manufactured deflectable elements which, driven electrostatically, are deflected in an oscillating manner. It is the object of the invention to provide a possibility with which a much larger deflection range can be utilized and in so doing the required voltage potential difference for the electrostatic drive of a deflection can be kept small and the occurrence of the pull-in effect can be avoided. In accordance with the invention, a deflectable element is present which is held at a frame element by at least one spring element and which can be deflected using an electrostatic drive. The deflection can be achieved by means of at least one counter-electrode and the deflectable element usable as an electrode.

Abstract: There is provided a method of driving an ultrasonic motor configured so that two alternating voltages having a predetermined difference between respective phases and having predetermined drive frequencies are applied to a laminated piezoelectric body that has driving parts abutting a member to be driven, whereby simultaneous excitation of vertical and bending vibrations and hence excitation of an elliptical vibration occur in the piezoelectric body, and the driving parts receiving drive force from the elliptical vibration drive the driven member. The method includes performing wear particle removal drive at a fixed frequency during regular reciprocal drive so as to intermittently interrupt the regular drive, the regular drive being such that the driving parts repeatedly reciprocally drive the driven member within a predetermined range, and the wear particle removal drive being such that the driving parts reciprocally drive the driven member within a removal drive range wider than the predetermined range.

Abstract: An oscillation device capable of generating a drive signal waveform with a sufficiently small number of harmonic components is provided. The oscillation device includes an oscillation system, a supporting unit configured to support the oscillation system, a drive unit configured to drive the oscillation system, and a drive control unit configured to control the drive unit by supplying a drive signal. The oscillation system includes a torsion spring and an oscillator. The drive control unit includes a drive-signal generating circuit configured to generate the drive signal using an address generator configured to generate an address to which a predetermined variable is added at a frequency higher than a frequency of the drive signal and using a trigonometric-function table indexed by an output of the address generator. The frequency of the drive signal is adjusted by adjusting the predetermined variable.

Abstract: A linear actuator includes permanent magnet annuli arranged about an armature core for axial movement in a tubular stator upon energization of coils arranged in concentric association with the armature. The stator has portions extending radially inwards of the coils and towards one another beneath each coil, which define a spacing between the coil and the armature. The annuli have a substantially radially magnetized structure and the coils are configured for single phase power input. In one embodiment (FIG. 6), two pairs of spaced annuli are arranged on the core, wherein the axial length of the outermost annuli is half the axial length of the inner annuli.

Abstract: An actuator (20) comprises a rotor (22); an electromagnetic circuit (24) configured to produce bidirectional torque on the rotor; and, a rotation limitation assembly (26). The rotor (22) comprises a rotor shaft and plural magnets (80) affixed to the rotor shaft. In an example embodiment the rotation limitation assembly (26) comprises at least one stationary clockwise boundary (40) configured to limit clockwise rotation of the rotor (22); at least one stationary counterclockwise boundary (42) configured to limit counterclockwise rotation of the rotor (22); and a rotor stop arm (50) connected to the rotor and configured to selectively abut the clockwise boundary (40) and the counterclockwise boundary (44) and thereby limit the rotation of the rotor to a predetermined angle about an axis of the rotor shaft.

Abstract: A method for position and/or speed control of a linear drive utilizing a converter having a control unit and being coupled to a motor of the linear drive. The method includes determining, in a sensor-free manner, a motor position, generating a motor position signal, generating an acceleration signal utilizing an MEMS accelerometer provided in the control unit and arranged on a moving part of the linear drive, mathematically converting the motor position signal and the acceleration signal to a speed signal, and utilizing the speed signal to control the linear drive.

Abstract: A driving controlling apparatus for a linear compressor, comprises: a storing unit for storing a reference phase difference to judge an overload state; and a controlling unit for judging an overload state based on a comparison result between the reference phase difference and a phase difference between a current and a stroke, and controlling a voltage or a current applied to a linear motor based on the judgement result.

Abstract: The present invention provides a method for controllably moving a plurality of antennae in a wireless communications system. The method comprises activating a first and second actuator associated with a first and second one of the plurality of antennae to move the first and second antennae to a desired position. The power delivered to the first and second actuators is measured, and at least one parameter of at least one of the first and second actuators is reduced in response to the measured power being greater than a setpoint.

Abstract: A method for driving an ultrasonic motor having an actuator section includes: a step of starting the ultrasonic motor by applying an AC voltage with a first frequency to the actuator section; a voltage detection step of detecting a voltage generated at the actuator section while lowering a driving frequency from the first frequency to a second frequency at which the ultrasonic motor stops; a starting step of starting the ultrasonic motor with a third frequency; and a driving step of changing the driving frequency from the third frequency to a lower frequency such that the driving frequency has a value within an operation frequency range, wherein the operation frequency range is within a range on a higher frequency side than the driving frequency at which a maximum voltage is detected in the voltage detection step.

Abstract: The present invention discloses an apparatus and method for controlling a linear compressor which can actively handle load and efficiently perform an operation, by synchronizing an operation frequency with a natural frequency of a movable member varied by the load.

Abstract: To provide a shape memory alloy actuator using a shape memory alloy that mechanically restrains a moving body in position to prevent oscillation, the actuator has a moving body pushing member adapted to be capable of abutting to the moving body, a bias spring for the moving body pushing member that exerts an external force on the moving body pushing member in the direction opposite to the direction of change in the shape of a shape memory wire caused by heating, a bias spring for the moving body that exerts an external force on the moving body in the direction same as the direction of change, a first stopper that restricts the movement of the moving body to a predetermined position upon cooling. One end of the shape memory wire is fixed, the other end is mechanically linked with the moving body pushing member.

Abstract: A sensorless method and apparatus for detecting piston collisions in a free piston linear compressor motor. The waveform of the back EMF induced in the motor stator windings is analysed for slope discontinuities and other aberrations in a time window centred on the back EMF zero-crossings. Waveform slope artefacts are indicative of piston collisions and cause the motor power to be decremented in response.

Abstract: An actuator driving apparatus comprises the following. A start signal generator generates a start signal having a frequency substantially equal to the resonance frequency of the movable portion of an actuator. A rock detector detects rock of the movable portion. A drive timing signal generator generates a drive timing signal based on the output of the rock detector. A switch is connected to the start signal generator and drive timing signal generator for selectively transmitting their outputs to a section arranged in a subsequent stage. A drive signal generator generates a drive signal based on the output of the switch, and supplies it to the actuator. A superposition preventing section prevents a frequency component of a frequency substantially equal to the resonance frequency from being superposed upon the output of the rock detector. The apparatus performs driving according to the rocking state of the movable portion, by switching the switch.

Abstract: A flat surface tilting device including a selectably positionable flat surface element assembly defining a flat surface element having a flat surface and a pivot location portion, the pivot location portion being generally centered with respect to the flat surface, a pivot support element pivotably engaging the pivot location portion, an electromagnet, fixed with respect to the pivot support element and arranged for application of magnetic force in a direction generally perpendicular to the flat surface thereby to pivot the flat surface element about the pivot support element, a sensor for sensing the position of the flat surface element and feedback circuitry operative in response to an output of the sensor to govern operation of the electromagnet.

Abstract: A servo driving method of the present invention to drive a stepping motor driven by a predetermined driving pulse, by a servo control method, is comprising a setting step of setting a driving mode of the stepping motor switchable at least between a first driving mode, in which the stepping motor is driven with a relatively large current, and a second driving mode, in which the stepping motor is driven with a relatively small current, and a switching step of switching the driving mode between the first driving mode and the second driving mode when a predetermined mode switching information is given. Thereby, it becomes possible to reduce the power consumption by supplying power efficiently to the stepping motor.

Abstract: A movable body apparatus includes a vibratory system, a driving portion for driving the vibratory system, a detecting portion for detecting a resonance frequency of the vibratory system, a drive controlling portion, and a storing portion. The vibratory system has a resonance frequency, and includes at least a movable body capable of being reciprocally, rotatably oscillated. The drive controlling portion regulates a driving frequency of a drive signal applied to the driving portion, based on the resonance frequency of the vibratory system. The storing portion stores the frequency detected by the detecting portion at a first predetermined time. The drive controlling portion regulates the driving frequency with reference to the stored frequency, at a second predetermined time after the storing portion stores the frequency, and executes a drive control of the vibratory system.

Abstract: The invention relates to an apparatus and to a method for controlling or regulating the deflection of micromechanically manufactured deflectable elements which, driven electrostatically, are deflected in an oscillating manner. It is the object of the invention to provide a possibility with which a much larger deflection range can be utilized and in so doing the required voltage potential difference for the electrostatic drive of a deflection can be kept small and the occurrence of the pull-in effect can be avoided. In accordance with the invention, a deflectable element is present which is held at a frame element by at least one spring element and which can be deflected using an electrostatic drive. The deflection can be achieved by means of at least one counter-electrode and the deflectable element usable as an electrode.

Abstract: The invention provides for a power steering assembly and method of actuation for assisting a driver in moving the steerable wheels of a vehicle. The power steering assembly includes a housing that defines a chamber. A steering rod is disposed in the chamber and is longitudinally moveable within the chamber. A shoulder is fixed to the steering rod and has opposing sides. A shaft is supported by the housing and engages the steering rod translating the rotational movement of the shaft into a longitudinal movement of the steering rod. A first actuator and second actuator are disposed in the chamber on opposing sides of the shoulder. The first and second actuators each have an excitable material that is controlled in a series of actuations to advance the actuators in a linear movement for pushing against the shoulder to move the steering rod longitudinally within the chamber.

Abstract: An apparatus and method for controlling an operation of a reciprocating compressor are disclosed in which a frequency is variably controlled to uniformly maintain a phase difference between current and stroke, a load is determined with a size of frequency at a point of time when the phase difference between the current and the stroke is uniformly maintained, and capacity is varied according to the determined load, to thus improve an operation efficiency. The apparatus for controlling an operation of a reciprocating compressor includes: a control unit for detecting a phase difference between current and stroke and outputting a frequency variable signal or a frequency detect signal based on the detected phase difference; a load detecting unit for detecting a current operation load according to the frequency detect signal; and a stroke reference value determining unit for determining a stroke reference value corresponding to the detected load.

Abstract: A method of controlling an electric motor includes providing an electric motor having a plurality of magnetically driven oscillatory elements having differing oscillatory characteristics, and an electromagnet having a coil arranged to drive all of the oscillatory elements. The method includes supplying an electric signal to the electromagnet, which creates a magnetic field that drives the oscillatory elements. The method also includes varying a frequency of the electric signal for individual control of oscillatory movements of the oscillatory elements.

Abstract: The invention applies to a vibrator comprising two pairs (A, B) of unbalanced rotors (10 to 13) driven in synchronous rotation by a first motor, and a second motor arranged to drive a phase shifter mechanism so as to adjust a phase difference between the first pair of rotors and the second pair of rotors; the system comprises: a sensor (C1) for sensing rotation of a rotor of the first pair of rotors; a sensor (C2) for sensing rotation of a rotor of the second pair of rotors, or for sensing the position of the phase shifter mechanism; means for controlling the rotation of the first motor as a function of the phase and the frequency of a force setpoint signal and as a function of the signals delivered by the sensors; and means for controlling the rotation of the second motor as a function of the phase, the frequency, and the amplitude of the force setpoint signal and as a function of the signals delivered by the sensors.

Abstract: An apparatus and method are disclosed to control an operation of a reciprocating compressor capable of precisely controlling an operation (stroke) of a reciprocating compressor regardless of a parameter of an internal motor of the reciprocating compressor and a mechanical error of the reciprocating compressor. The apparatus for controlling an operation of a reciprocating compressor which determines a stroke estimate value corresponding to a point when a discharge valve of the reciprocating compressor is opened as a stroke reference value, and controls a voltage applied to the reciprocating compressor according to the determined stroke reference value.

Abstract: An apparatus and method for controlling operations of a reciprocating compressor are disclosed. The apparatus includes a compressor control factor detecting unit for detecting a compressor control factor to detect a stroke value corresponding to a point where TDC (Top Dead Center)?0 on the basis of a stroke estimate value of a reciprocating compressor and values of a current and a voltage applied to a motor of the reciprocating compressor; a stroke reference value determining unit for determining a stroke reference value on the basis of the detected compressor control factor; and a controller for varying a voltage applied to the reciprocating compressor according to the determined stroke reference value.

Abstract: An oscillator device includes an oscillation system 115 having a plurality of oscillators and a plurality of torsion springs, a supporting member for supporting the oscillation system 115, driving members 114 and 1152, a signal output device 121 and 122, and a drive control unit 101-113, 123 and 124, wherein the driving member drives the oscillation system 115 so that the oscillator provides oscillation presented by an equation including the sum of a plurality of periodic functions, wherein the signal output device produces a signal corresponding to the displacement of the oscillator, and wherein the drive control unit controls the driving member based on an output signal of the signal output device and by use of a driving signal which is expressed by an equation including the sum of a plurality of periodic functions, the drive control unit including a driving signal generation circuit 109 for generating a driving signal using a trigonometric function table 110.

Abstract: A device for generating a motive force includes a tubular housing, a driving member, and a magnetic unit. The driving member is movably disposed in the tubular housing and includes a magnet. The magnetic unit includes first and second magnets, each of which covers a respective one of first and second open ends of the tubular housing. The construction as such permits alternate reversal of a polarity of a magnetic field of the magnet of the driving member to cause reciprocating movement of the driving member in the tubular housing.

Abstract: The present invention is a method for modifying a current gas or diesel engine, or building a new one, which utilizes a magnetic field produced by solenoids in the cylinders or cylinder cover to exert force on a modified piston to turn a crankshaft. The present invention removes the need for fuel and eliminates emissions. The present invention utilizes the alternator in normal operation to provide the current through the solenoids to produce magnetic fields. Vehicle speed is controlled by changing the amount of current going through the solenoid. This process changes the magnitude of the originating and induced magnetic fields of the solenoid and piston. The operation of the vehicle remains similar to traditional operation, except the greatly beneficial aspects of not needing fuel or producing emissions.

Abstract: A method for providing an operable filter system for filtering particles out of a beam of radiation in lithography is disclosed. The method includes providing a slack foil or wire for intercepting the particles, mounting at least a first point or side of the foil or wire to a first position of a mounting assembly, and substantially stretching the slack foil or wire at least within the beam of radiation, substantially parallel to a direction in which the radiation propagates.

Abstract: Disclosed herein is a power device. The power device has a power source; timing circuitry powered by the power source for producing a current pulse output having a pulse width; a switch for triggering the current pulse output produced by the timing circuitry; an armature motor powered by the power source and in electrical communication with the timing circuitry for receiving the current pulse therefrom, the armature motor comprising: an electro-magnetic core; a first winding for carrying electric current to energize a magnetic field associated with the electro-magnetic core; a second winding for carrying current to reset the magnetic field associated with the electro-magnetic core, the first and second windings wound about the electro-magnetic core; and a swinging armature for providing movement in response to the energizing of the magnetic field about electro-magnetic core. The first winding and the second winding are bifilar wound together about the electro-magnetic core.

Abstract: Disclosed are an apparatus for controlling a driving of a reciprocating compressor capable of enhancing an efficiency by differently controlling a frequency and a stroke voltage according to a load size and capable of reducing consumption power, and a method thereof. The apparatus comprises a controlling unit for judging a load size by comparing a phase difference between a detected current and a stroke with a reference phase difference, and outputting a frequency control signal and a stroke control signal according to the judged load size.

Abstract: A system for controlling a linear compressor, generates freezing force as a piston reciprocates according to rotation of a motor which receives alternating current power through a triac. The system includes a controller which moves up or delays a trigger signal corresponding to an absorption cycle or a compression cycle, such that the center point of the piston reaches a resonant point when a current and a phase difference of the motor deviate from predetermined ranges.

Abstract: An apparatus and method for controlling an operation of a reciprocating compressor are disclosed. The apparatus for controlling an operation of a reciprocating compressor includes: a current phase delay value generating unit that calculates a current phase delay value by using a current stroke and a detected current and outputting the calculated current phase delay value; and a reference current generating unit that delays a reference current based on a difference between the current stroke and a stroke reference value according to the current phase delay value. A phase difference between a current and a pulse width modulation (PWM) voltage is estimated, a phase delay value for compensating the estimated phase difference is calculated, and a reference current is delayed as much as the calculated phase delay value for a certain time to thus remove a current distortion phenomenon.

Abstract: The drive method consists in setting in vibration a moving mass of a vibrating device for a portable object using a series of voltage pulses provided to the coil of the vibrating device, which is electro-magnetically coupled to the moving mass. In a phase of driving the oscillations of the moving mass after a start phase of the vibrating device, followed by a resonant frequency measurement phase, successive rectangular voltage pulses of alternating polarity are provided to the coil by a drive circuit. The width of the successive pulses is modulated in a substantially similar manner during each successive oscillation period which allows a substantially sinusoidal voltage wave (SF) of determined amplitude to be defined whose fundamental frequency is adapted to the resonant frequency of the moving mass. By modifying the oscillation period, it is thus possible to act on the amplitude of the moving mass oscillations which depends on the sinusoidal wave amplitude defined by the rectangular pulse width modulation.

Abstract: A device for adjusting the armature stroke in a reversible linear drive unit comprising an excitation coil and an armature displaceable in the magnetic field of the excitation coil according to a linear oscillating motion at a predefined armature stroke. The device comprising systems for detecting the current armature position, systems for measuring the actual excitation coil current and systems for adjusting the excitation coil current in such a way that the armature is exactly supplied with electric energy for obtaining the aptitude of oscillations of the armature stroke during each half-wave of the armature motion.

Abstract: A vibration device comprises a motor having a stator and a rotor each having one or more magnetic elements. A magnetic element on at least one of the rotor and the stator comprises an electromagnet which can be supplied with an electric current so as to interact with a magnetic element on the other of the rotor and the stator to cause rotation of the rotor with respect to the stator; and the one or more magnetic elements of the rotor, considered together, have a center of mass which is offset from the axis of rotation of the rotor. The rotor and the stator are arranged in, or together form, a cavity containing a liquid.

Abstract: In an electromagnetic driver according to the invention, electromagnetic units are arranged in the axial direction of a shaft, and a power supply change-over device is so formed that, when an attractive magnetic field arises between the coil unit and the magnetic unit of the one of the electromagnetic units, a repulsive magnetic field is generated between the coil unit and the magnet unit of the other of the electromagnetic units. As the polarity is alternately changed over by the power supply change-over device when a direct current is supplied to the exciting coils of the electromagnetic units, the coil unit or the magnetic unit reciprocates, and further the shaft reciprocates in the axial direction.

Abstract: An apparatus and a method for controlling operation of a reciprocating compressor is capable of reducing a stroke estimation error by eliminating an error that occurs due to resistance and inductance of a compressor motor by estimating a stroke with a counter electromotive force induced by a searching coil. Furthermore, by leaving errors of inductance and resistance, among all motor parameters, out of consideration in stroke estimation, a stroke estimation error can be reduced.

Abstract: A frequency control circuit including a control circuit for setting a set value, an adding circuit for adding the set value per unit time and effecting counting based on the adding result, and a signal output circuit for outputting an alternating signal of a cycle corresponding to the time necessary for the count result by the adding circuit to reach a target value. The control circuit sets the set value as a value which does not correspond to a submultiple of the target value, and the adding circuit starts the counting of a next cycle when the count result reaches the target value. The control circuit further sets an initial value of the counting of the next cycle in accordance with a value of a portion of the adding results, exceeding the target value when the count result reaches the target value.

Abstract: A driving unit of the present invention comprises a moving element, an elastic body configured to support the moving element, a permanent magnet fixed on said moving element, an electromagnet disposed to be opposed to said permanent magnet, and a controller. The moving element and the elastic body constitute a resonance system. The electromagnet includes a magnetic material and a coil wounded around the magnetic material. The controller magnetizes the magnetic material by feeding a current through the coil and gives a vibration force to the moving element by magnetic force acting between the magnetic material and the permanent magnet. The feature of the present invention resides in that the controller determines a current waveform necessary for an intended motion of the moving element, and applies a voltage to the coil intermittently so that a current in the form of the current waveform flows through said coil.

Abstract: Disclosed herein is a power device. The power device has a power source; timing circuitry powered by the power source for producing a current pulse output having a pulse width; a switch for triggering the current pulse output produced by the timing circuitry; an armature motor powered by the power source and in electrical communication with the timing circuitry for receiving the current pulse therefrom, the armature motor comprising: an electro-magnetic core; a first winding for carrying electric current to energize a magnetic field associated with the electro-magnetic core; a second winding for carrying current to reset the magnetic field associated with the electro-magnetic core, the first and second windings wound about the electro-magnetic core; and a swinging armature for providing movement in response to the energizing of the magnetic field about electromagnetic core. The first winding and the second winding are bifilar wound together about the electro-magnetic core.

Abstract: The present invention discloses an apparatus for controlling an operation of a reciprocating compressor and a method therefor which can reduce errors in an operation of a stroke estimated value of the reciprocating compressor, by previously preventing over-saturation of a magnetic flux density generated in a coil of a motor. The apparatus for controlling the operation of the reciprocating compressor includes a magnetic flux saturation constant operation unit for operating a magnetic flux saturation constant of a motor of the reciprocating compressor on the basis of a stroke estimated value of the reciprocating compressor, a stroke reference value generation unit for generating an increased or decreased stroke reference value by increasing or decreasing a predetermined stroke reference value on the basis of the magnetic flux saturation constant, and a control unit for controlling a voltage applied to the motor of the reciprocating compressor on the basis of the generated stroke reference value.

Abstract: An actuator driving apparatus comprises the following. A start signal generator generates a start signal having a frequency substantially equal to the resonance frequency of the movable portion of an actuator. A rock detector detects rock of the movable portion. A drive timing signal generator generates a drive timing signal based on the output of the rock detector. A switch is connected to the start signal generator and drive timing signal generator for selectively transmitting their outputs to a section arranged in a subsequent stage. A drive signal generator generates a drive signal based on the output of the switch, and supplies it to the actuator. A superposition preventing section prevents a frequency component of a frequency substantially equal to the resonance frequency from being superposed upon the output of the rock detector. The apparatus performs driving according to the rocking state of the movable portion, by switching the switch.

Abstract: A circuit configuration for driving an electric motor, in particular of a washing machine, includes power switches connected to connection terminals of the electric motor and to a voltage intermediate circuit. A driver circuit is connected to the voltage intermediate circuit and to the power switches. A control unit, in particular a micro controller, is connected to the driver circuit. The control unit generates control signals for controlling at least one rotation speed of the electric motor. The driver circuit generates short-circuit control signals for driving the power switches, which bring about a short circuit of the connection terminals connected to the power switches, independently of the control signals from the control unit. The driver circuit generates the short-circuit control signals as a function of a detection of an overvoltage of the voltage intermediate circuit over a desired voltage range. A method for controlling an electric motor is also provided.

Abstract: A linear vibration motor comprises: a stator provided with one of a permanent magnet and an electromagnet including a winding; a vibrator provided with the other of the permanent magnet and the electromagnet and supported to be able to vibrate; a movement detection unit for detecting movement of the vibrator; a control output unit for supplying electric power to the winding of the electromagnet based on an output of the movement detection unit so as to generate vibration of the vibrator; a rechargeable battery for supplying electric power to the control output unit; and a power supply unit for supplying electric power to the control output unit and to the rechargeable battery, wherein the power supply unit supplies electric power in an intermittent mode with synchronized timing such that the timing of the intermittent power supply is synchronized with the timing of the power supply to the winding.

Abstract: A motor driving apparatus for driving a linear vibration motor having a spring member that supports a mover so as to form a spring vibration system including the mover. The motor driving apparatus employs an accurate spring constant of the spring member corresponding to an individual linear vibration motor at a position calculation for obtaining the position of the mover during the operation, thereby increasing the accuracy of the position calculation. The motor driving apparatus includes a mover force vibration unit for making the mover of the linear vibration motor freely vibrate, a relative position detection unit for detecting a timing when the freely vibrating mover passes through a fixed point (relative position), and a natural frequency detection unit for detecting a natural frequency of the mover based on output information from the relative position detection unit, thereby calculating the spring constant based on the detected natural frequency.

Abstract: The position and speed and, in some embodiments, direction of rotation of a motor for turning the rod of an object such as a window covering is determined by placing a braking magnet next to the motor and a piezoelectric element between the braking magnet and motor. As the motor rotates, the piezoelectric element generates a signal that can be used to determine the speed of rotation and also the position of the motor (and, hence, the position of the object being moved). The magnet brakes the motor from turning under the weight of the object when the motor is deenergized.

Abstract: A driving apparatus of a linear motor which reciprocally drives a movable element supported by an elastic member, includes an inverter that converts a direct current power into an alternating-current power with a specified frequency to drive the linear motor, a current detector that detects the output current of the inverter, a voltage detector that detects the output voltage of the inverter, an amplitude detector that detects an amplitude of the movable element of the linear motor, an amplitude controller adjusts the output current or output voltage in a first control cycle so that the amplitude of the movable element is a desired constant value, and a resonant controller that adjusts the output frequency of the inverter in a second control cycle which is larger than the first control cycle so that the output current of the inverter is substantially minimum on condition that the amplitude is substantially constant.