Abstract: In a motor driver, based on driving waveforms of respective phases generated by a driving waveform generator, a power feeder feeds respective phase-coils with an alternating current consecutively changing in sine wave. Further, a phase advancing controller adjusts phases of the driving waveform, and performs phase-advancing control such that each phase of back electromotive forces induced in respective phase-coils generally coincides with a phase of the ac running through the coils. In phase-advancing controlling, a phase current is detected with a common current. The structure discussed above can reduce torque ripples, vibrations and noises, and a motor thus can be driven efficiently.

Abstract: A method for implementing control signal linearization for an electric motor is disclosed. In an exemplary embodiment, the method includes receiving a desired voltage command to be applied to the motor and determining whether the magnitude of the desired voltage command falls between a first value and a second value. If the magnitude of the desired voltage command falls between the first value and the second value, then modulating a voltage command between the first and the second value over a determined sample period, thereby resulting in the application of a modulated voltage command to the motor.

Abstract: Embodiments of the present invention are directed to gear based transmission apparatus that are configured to reduce or eliminate the backlash effects. In one embodiment, a transmission apparatus comprises a follower gear, a first drive gear set coupled with the follower gear to drive the follower gear, and a second drive gear set coupled with the follower gear to drive the follower gear. The first drive gear set includes at least one gear, and the second drive gear set includes at least one gear. A controller is coupled with the first drive gear set and the second drive gear set.

Abstract: A motor abnormality detection apparatus is capable of performing the abnormality detection of a motor (5) without supplying a special electric current thereto for abnormality detection in an ordinary control state. A motor control device (100) controls the motor (5) through vector control which is described by a two-phase rotating magnetic flux coordinate system having the direction of a field current as a d-axis direction and a direction orthogonal to the d-axis direction as a q-axis direction. A motor abnormality detection part (100h) (100h) performs an abnormality determination of the motor based on target impression voltages (Vd*, Vq*) impressed on the motor (5).

Abstract: A brushless motor apparatus includes a motor section including delta-connected three-phase coils; a switching section electrically connected to the motor section via a line; and a driving section for controlling an ON state and an OFF state of the switching section so as to drive the motor section. In the brushless motor apparatus, r1+r2<2R, where r1 is an internal resistance of the switching section in an ON state, r2 is a resistance of the line connecting the motor section and the switching section, and R is a direct current resistance of each of the three-phase coils.

Abstract: A magnitude of current that does not cause electric power generation is supplied to a field winding of a movable element, and an induced voltage generated in a armature winding of a stationary element is measured. A position of the movable element is determined from the measured induced voltage. In addition to the thus-determined position of the movable element, a position of the movable element measured on a different basis is used to measure an error regarding the position of the movable element.

Abstract: In order to provide a driving device for a motor having a capability equivalent to conventional vector control type sensorless method by simplifying the controls structure to reduce number of parts to be adjusted, and to stabilize the control system, a driving device for a synchronous motor does not include a speed controller or a current controller, and calculates a voltage impressed on a motor on coordinate axes (dc/qc axes) based on a magnetic pole axis. For calculating a voltage command, command values such as a rotation speed command and a current command are used, and Iq* corresponding to a torque current command is calculated and provided based on a detected current value.

Abstract: A direct-current power supply (40) is connected between the neutral points of two three-phase coils (24, 26) of a 2Y motor (22) constituted of the windings of the two three-phase coils (24, 26), which are connected in Y-connection and wound on a same stator, and to which three-phase alternating current power is severally supplied with a phase difference of a shifted angle between the windings from two inverter circuits (30, 32) having a positive pole bus (34) and a negative pole bus (36) for common use. A capacitor (38) is connected between the positive pole bus (34) and the negative pole bus (36). The electric potential difference between the neutral points of the three-phase coils (24, 26) is made larger or smaller than the voltage of the direct-current power supply (40) through the switching control of the inverter circuits (30, 32). Thereby, the capacitor (38) can be charged or discharged. Consequently, an inverter input voltage can be adjusted within a wide range.

Abstract: A mechanical filter and control system combination for a robot or manipulator is provided. The control system directs movement of the manipulator based on feedback of sensed contact force on the manipulator. The mechanical filter is arranged between the force sensor and the end effector of the manipulator to perform positive real compensation of the admittance response of the manipulator produced by just the force feedback control system. The mechanical filter can consist of a spring and a damper arranged in parallel.

Abstract: Provides a control unit for an electric power steering apparatus with improved steering performance by recognizing a turn and a return of a steering wheel in a steering wheel return control, and by employing information on a steering angular velocity in calculating a current. This control unit controls a motor for giving steering assist force to a steering mechanism based on a current control value calculated from a steering assist command value calculated based on the steering torque generated in the steering shaft, and a current value of the motor. A steering wheel return controller for applying a steering wheel return control signal to the steering assist command value is provided, thereby to execute the steering wheel return control only when the steering wheel returns.

Abstract: The invention concerns a motor controller for a motor with a feedback potentiometer, preferably for central air valve actuation. In the field of climate control, for example for utility vehicles and motor vehicles, the air ducts in heating, air conditioning and/or ventilation systems have valves to control the flow of air or water. These valves are adjusted either mechanically, e.g. by Bowden cables or flexible shafts, or using motors. It is proposed that a continuous rotation potentiometer be employed as a feedback potentiometer and specially designed control electronics be used to control a motor with the continuous rotation potentiometer. In the control electronics for the motor controller, an angular difference between an adjusted control potentiometer and the motor feedback potentiometer is determined in order to determine therefrom the shortest adjustment path to the chosen setpoint position for the motor when the angular difference is greater than 180 degrees.

Abstract: The invention relates to a method for regulating an electric-motor-driven adjusting device, in particular for vehicles, having a safety circuit (5) for reversing or stopping a drive motor, and to an apparatus for performing this method. To enable fast, safe detection in the event of something becoming caught or pinched, it is provided that an actual value is regulated via a closed-loop control circuit to a set-point value, the actual value or set-point value is a signal having a frequency proportional to the rpm or load on the drive motor, and the phase difference detected with a comparison member of the control circuit is utilized to activate the safety circuit.

Abstract: A machine includes an electric drive motor and at least one component carrying out a periodic motion. The machine is configured to control the drive motor in such a manner that it applies a predetermined torque to the machine.

Abstract: A motor driver includes a driving waveform generator simply constructed. Because the generator produces a waveform having rather small numbers of steps divided and voltage levels divided. Respective phase-driving signals responsive to a step-like voltage waveform produced by the generator are applied to a power feeder, so that an alternate current—shaping in a sine wave and changing sequentially—runs through respective phase-coils. Further, phase-advancing control realizes phase agreement between respective phase-currents and back electromotive force generated each of the respective phases. As a result, a motor can be driven efficiently with less torque ripples, vibrations and noises.

Abstract: A brushless DC-motor driving controller is provided which can significantly reduce torque fluctuations in the brushless DC motor. The brushless DC-motor driving controller uses a position detector, generates rotation-angle signals representing rotor-rotation angles or a part thereof in high resolution, uses the rotation-angle signals, and performs rectangular-wave driving. By using the rotation-angle signals, the brushless DC-motor driving controller compensates for electrical angles corresponding to commutation-position skews in rectangular-wave driving which are caused by armature reaction in a brushless DC-motor.

Abstract: This invention relates to a method for braking a washing machine comprising the steps of: determining whether or not a motor is braking; transmitting a PWM (Pulse Width Modulation) control signal by setting up the initial phase and the duty ratio according to the voltage flows in the system when an operation mode determined by the previous step as a braking mode; comparing a capacity and a variance of the detected voltage with a reference voltage predetermined during the previous step; and controlling a motor driver by re-establishing the control phase and the duty ratio are re-established until the motor is stopped when the comparison result of the previous step indicates that the capacity and the variance of the voltage are lower than the predetermined reference level.

Abstract: A method and apparatus for actively controlling the energization of the stator windings of a rotating electromagnetic machine to actively overcome any tendency of the rotor of the machine to prefer certain angular positions with respect to the stator over other angular positions.

Abstract: A motor rotation control device for an optical disk player including a motor outputting rotation signals, a sensor for sensing the rotational direction and rotational state of the motor in response to rotation signals of the motor, a motor control signal generator for generating a motor control signal according to the rotational direction and rotational state of the motor, and a motor rotation controller for controlling the rotation of the motor in response to the motor control signal. The motor rotation control device operates independently of a system controller, thereby reducing the load on the system controller.

Abstract: A novel low cost limited angle torque DC brushless servomotor is disclosed. The motor itself is a modified standard low cost DC brush motor which is modified by removing the brush assembly and substituting in its place an appropriately configured multiconductor flexible circuit which is coupled between a controller, the commutator and a magnetic rotor shaft angular displacement sensor. The flexible circuit has a dual function—it provides on one hand the conduit for electrical communication between the controller and the commutator and on the other hand between the sensor and the controller. Part of the circuit is supported between a bearing assembly and the commutator and flexes in consonance with the controlled limited angular rotation of the rotor without affecting performance or reliability of the motor. The rest of the circuit remains stationary during motor operation. The bearing assembly supports the sensor and is used to mount the motor in a housing for a pneumatic servovalve or the like.

Abstract: An improved motor starter assembly is provided on a frame and having an external profile which matches that or is within that of a prior motor starter is disclosed. The improved motor starter assembly provides a soft start circuit within the profile. Retrofitting of prior art motor starters is accomplished by moving the power fuses and related hardware of an existing medium voltage (2.4 Kv to 7.2 Kv) and installing the new soft start circuit on the frame of the existing motor starter. The retrofitted arrangement mounts the motor fuses horizontally and the vacuum contactors vertically in an arrangement to provide enough space within the external profile to mount the soft start circuit arrangement.

Abstract: A full-automatic washing machine includes an outer tub, a rotatable tub rotatably mounted in the outer tub, an agitator rotatably mounted in the rotatable tub, and a brushless motor for direct driving at least one of the rotatable tub and the agitator. The brushless motor including windings of a plurality of phases and a rotor. Also, the washing machine includes rotor position detecting elements to detect a rotational position of the rotor. The rotor position detecting element are less in number than the phases of the motor. An energizing signal forming element to generate a sinusoidal energizing signal for each of the phases based on the detected rotational position of the rotor. Last, a driving element to energize the windings of the phases based on the energizing signals.

Abstract: A control device controls operation of a brushless DC motor in such a way that the motor is started and accelerated up to a predetermined rotational speed by applying driving voltage formulated based on a synchronous signal under a startup-drive-mode and the driving mode is switched, after the predetermined rotational speed is established, to a self-controlled-drive-mode in which the driving voltage is formulated based on signals indicating an angular position of the rotor relative to the armature. In the transient period for switching-over from the start-up-drive to the self-controlled-drive, phase difference between the driving voltage and the rotor position signal is detected for a period covering more than one rotation of the rotor, the switching-over is carried out only when the phase difference is sufficiently small to avoid a motor stall or an excessive shock.

Abstract: A frequency detector for a PLL controller, the controller being for generating an output signal to control a motor driver electrically connected to a motor having multiple phase windings arranged as a stator and a rotor having a permanent magnet or a DC current excitation winding for rotating the rotor, the motor driver selectively establishing current paths through selected windings in response to said output signal, to provide maximum torque to the rotor based on the rotational position of the rotor relative to the windings, the frequency detector comprising a monitor for detecting a number of pulses in said output signal during a time period between a first and a second rotational position of the rotor relative to the windings and a governor for generating a frequency control signal as a function of said number of pulses, wherein the PLL controller generates said output signal at output frequencies selectively as a function of said frequency control signal, whereby the frequency detector minimizes a differ

Abstract: A motor drive control apparatus has a number of revolution setting circuit, a driving circuit for driving a motor to rotate at a predetermined number of revolution based on a number of revolution command signal output from the number of revolution setting circuit, a number of revolution detecting circuit for detecting the number of revolution of the motor, a driving voltage adjusting circuit for adjusting a level of the driving voltage of the motor to be supplied to the driving circuit, a motor control circuit including a PLL control circuit for controlling the number of revolution of the motor so that the phase difference between the phase of the number of revolution command signal and the phase of the number of revolution detection signal becomes within a predetermined range of value, and a voltage control circuit for instructing the driving voltage adjusting circuit to adjust the driving voltage of the motor to be at a level in the vicinity of the PLL controllable minimum level.

Abstract: A balanced and synchronized phased detector circuit is provided for a three phase power controller for AC induction motors. The power controller includes a thyristor or switching element for each motor phase winding between a line phase terminal of a three power line and the motor's input terminals, and decides the sequence for firing the thyristors. The phase detector includes a dividing resistor network between each phase's line terminal and the front-end operational amplifiers used in the phase detector, and an adjustable dividing resistor network between each motor terminal and the front-end operational amplifiers. The resistor networks allow a differential voltage to be set between the phase line terminal and the motor terminal for each phase, to a voltage appropriate for firing the respective thyristor. By allowing control over the front-end differential voltage, the phase detector virtually elements vibrations encountered during operation of the motor.

Abstract: A disk drive including firmware for overcoming stiction and breaking free the heads of a disk drive which may adhere to the disk surface when the disk is at rest. Upon start-up of the disk drive, if stiction at the head/disk interface occurs, the voltage to the spindle motor and/or actuator motor may be rapidly fluctuated so as to cause a pulsing of the spindle motor and/or actuator motor. Pulsing both the spindle motor and actuator motor creates forces in a plurality of radial directions to allow the head(s) to break free from the disk(s) in the direction of least resistance. Moreover, as the resonant frequency of the spindle motor varies depending on the number of heads that are stuck, the firmware pulses over a range of frequencies including the various resonant frequencies of the spindle motor corresponding to various numbers of heads stuck.

Abstract: In a brushless DC motor system, an RMS value of an input current of a voltage-fed inverter (702) is detected by a current transformer (705) and an RMS value detector circuit (706). A rotation speed of a brushless DC motor (703) is detected based on a cycle of a position signal outputted by a position sensor circuit (704). Then, in response to the RMS value of the input current and the rotation speed, the phase of the inverter output voltage relative to the phase of the motor counter-electromotive voltage is set to a phase at which the motor efficiency comes generally to a peak, and a switching command to the voltage-fed inverter (702) is generated. With this constitution, when the applied voltage waveform is controlled only by the voltage-fed inverter in response to the rotor-position detection signal, the motor attains high-efficiency operation without involving any increase in cost and yet regardless of load conditions.

Abstract: A method and A circuit for detecting an auto tracking find error in a VCR, wherein a phase control range for a capstan motor is widened as compared with the prior art so that, when a phase of the capstan motor is widely detuned, the following speed for stabilization of the phase of the capstan motor can be made fast. According to the invention, in an interval of -.pi.-.pi. of the phase of the capstan motor, first latch data is selected as a phase error signal for control of the phase of the capstan motor. In intervals of -2.pi.--.pi. and .pi.-2.pi. of the phase of the capstan motor, second latch data is multiplied by two and is then of the same polarity as that of the first latch data. The second latch data multiplied by two is added to the first latch data. In result, the added value is selected as the phase error signal. Also, a portion of the data above double the upper limit value is cut in the interval of -2.pi.--.pi.

Abstract: The present invention relates to a current supply control apparatus capable of actuating a large inductance load at a low electric power source voltage and also capable of improving a responsibility in a current supply control of the inductance load. When a detecting voltage of an absolute value circuit (10) representing a current value flowing in an exiting coil (1), provided as an inductance load, exceeds a standard voltage, transistors (3a, 3b) interposed between a DC electric power source (2a, 2b) and the exciting coil are turned off, and a magnetic energy stored in the exciting coil is utilized to charge a capacitor (5) up to a high voltage so that a current flowing after the transistors have been turned off is quickly reduced.

Abstract: A method for reducing effects of torque fluctuations on a system driven by an electric motor and producing cyclically occurring, rotational speed-dependent load-torque fluctuations includes counteracting changes in load torque by effecting oppositely directed changes in drive torque so as to maintain the load torque at an approximately constant value.

Abstract: Apparatus for activating a safety device hingedly mounted on a shool bus to swing it out to an outstretched position when the bus door is opened and to return the device to its retracted position when the bus door is closed. The system includes a control switch which is caused to close when the door is opened and to open when the door is closed. Associated with the control switch is a control circuit for connecting a DC power supply to a unidirectional DC motor operatively coupled through an eccentric drive and a link arm to the safety device whereby in the course of a single cycle of motor rotation, during one half of the cycle the device is caused to swing out to its fully outstretched position, and during the other half, the device is caused to return to its fully retracted position.

Abstract: A variable speed controlled induction motor has a rotor (8) formed in one piece and a plurality of stators (24,25), the rotor having a plurality of rotor cores (2,3) and a plurality of conductive members (5) interconnected and the stators having respective stator windings (22,23). The stator windings (22,23) are connected in series, the rotor conductive members (5) are short-circuited by connecting members (r) at an air space or a non-magnetic core portion disposed between the rotor cores (2,3), and at least one of the plurality of stators (24,25) is associated with a phase shifter (38;47;50;51) providing the voltage of a given phase to the stator windings, whereby the rotational speed can be controlled easily over a wide range with excellent torque characteristics and efficiency.

Abstract: In order to correct errors in a synchro control transmitter, the error in the transmitter is measured at equal angular increments, the magnitude and phase of the maximum error of the second harmonic determined and resistors placed across two pairs of the three transmitter outputs selected such as to establish a second harmonic load unbalance which is approximately equal in magnitude and opposite in phase to the measured error.