Abstract: A booster circuit for a pre-drive circuit of a brushless direct current single-phase motor. When a series pair of power FETs of the drive circuit turn on, one boost control switching element of the pre-drive circuit turns on, another series pair of power FETs of the drive circuit turn off, and the other boost control switching element of the pre-drive circuit turns off. The booster circuit provides a continuous stable output voltage to the motor.

Abstract: The invention relates to a failure detection system for an electric power steering system. The system detects ON failure of one of first to fourth switching elements of an H-bridge circuit of the electric power steering system. The system detects ON failure by measuring the value of the current and the fluctuation in the value of the current. Therefore, the system can detect ON failures even when the value of the current is within normal ranges.

Abstract: An electrical drive apparatus, in particular, a motor-driven motor vehicle window winder or motor vehicle belt roller, which can be operated via a full bridge circuit with at least four switching elements with a different load depending on the rotation direction, wherein the switching elements are individually designed on the basis of their different maximum loads, in the sense of an asymmetric full bridge.

Abstract: An electric machine having a stator assembly that includes a stator core and a coil supported by the stator core and a rotor assembly that includes a shaft and a rotor supported by the shaft that is in magnetic interaction with the stator core. The electric machine may include a single sensor configured to detect magnetic polarities of the rotor as the rotor rotates relative to the sensor and to generate a signal representing the detected magnetic polarities of the rotor. The signal and an inverted version of the signal are utilized to control current through the coil. The current may be controlled indirectly by controlling the application of voltage to the coil. The sensor may be encapsulated on a circuit board to positively position the sensor relative to the circuit board. The circuit board may be mounted to a bearing housing of the electric machine. The sensor may be received in a pocket of a bearing housing of the electric machine so the sensor is positively positioned relative to the rotor.

Abstract: An elect power steering apparatus includes a motor drive circuit for PWM-driving an electric motor to generate a steering assist torque corresponding to a steering torque. The motor drive circuit includes a bridge circuit formed by a plurality of FETs, and a predrive circuit for driving FETs at a positive potential. Series connected first and second voltage step-up circuits for stepping up a line voltage at two stages are provided in front of the predrive circuit so that the FETs are driven by the predrive circuit with an output voltage from the second voltage step-up circuit supplied to the predrive circuit.

Abstract: A drill/driver (e.g. an electric drill) with a screwdriver bit attachment, and a method of controlling the drill/driver, are described. This method of control will greatly reduce the occurrence of stripped screw heads on most types of screws. By periodically stopping insertion of a screw and reversing direction of the screwdriver bit, the screwdriver bit will be reinserted fully back into the screw head. By ensuring the screwdriver bit is always fully inserted in the screw head, the stripping of a screw head will be prevented. This can be easily implemented on most types of powered screwdrivers including the most common device used for screw insertion on a construction job site, the cordless drill/driver.

Abstract: A control system controls a DC motor which operates a shifting mechanism. The control system includes switch circuit with a plurality of switches which connect terminals of the motor to a power supply. In order to limit the speed and torque, the control system operates the DC motor via pulse-width modulation so that the DC motor is alternately operated in a supply mode and in a short-circuit mode. The alternating supply and short-circuit modes result in operating states in which the motor is alternately driven and decelerated. Consequently, the speed and torque of the DC motor can be limited by the pulse-width modulation of control signals.

Abstract: A rotary brushless electric motor is formed within a cylindrical rotor housing structure that surrounds an annular stator ring. The stator is formed of a plurality of individual power modules and corresponding core segments, each module including electrical control and drive elements supplied by a power source incorporated within the stator. Such parallel architecture provides relatively independently controlled functionality for each module. Each module and stator core segment can be individually installed and removed without disturbing the other units. Should a particular module or stator core segment fail, it can be easily removed for repair or replacement and reinstallation.

Abstract: A motor controller for an electric motor having a plurality of motor terminals is connected to a power supply and comprises a commutation control, a current sensor, a peak target circuit, a pulse width control and a reverse current control. The commutation control is connected to the motor terminals for causing current pulses to flow through selected terminals during each commutation state. The current sensor provides a sense signal representative of the current pulses, and the peak current target circuit provides a target signal. The pulse width control controls pulse width of the current pulses as a function of the sense signal and the target signal. The reverse current control prevents reverse current from flowing into the power supply during change of commutation state.

Abstract: A pre-drive circuit for a brushless DC single-phase motor permits a cost reduction and an easy adjustment for the control input voltage of a switching device adjacent to a power source in a wider range, especially in increasing the control input voltage. In a drive circuit having four switching devices making up an H-bridge circuit with a motor coil being sandwiched therebetween, a control voltage exceeding a power supply voltage is required to turn ON the switching devices adjacent to the power source. The pre-drive circuit changes the duty ratio of the control voltage controlling motor speed. A circuit unit for generating pulse signals for controlling the switching devices uses an inexpensive logic circuit.

Abstract: A method of limiting current in a DC motor acts on a full bridge circuit (137) through which the stator winding arrangement (102) of that motor is supplied with current. Upon response of the current limiter, energy supply to the stator winding arrangement (102) from the DC power network is interrupted. The stator winding arrangement is then operated substantially in short circuit via semiconductor switches of the full bridge circuit, and the decaying current flowing in that context serves substantially to continue driving the motor. When that current has reached a lower value, energy supply from the DC power network to the motor is once again activated. The effective value of the current flowing to the motor is preferably reduced when the current limiter responds. The time period during which that current flows, in the form of current blocks, is then increased in compensatory fashion.

Abstract: An electric power steering removes external wiring connecting between an electric motor and a control unit, whereby the influence of radiation noise caused by a PWM operation can be reduced. In addition, the heat radiation and assemblability of the electric motor and the control unit can be improved, while achieving high power output. A housing 64 with a metal substrate 61 fixedly secured thereto is arranged at a side opposite to an electric motor 30. The cooling fins are formed on an outer side of a housing 64 and on an outer side and an inner side of a cover 65. A metal substrate 61, a large current substrate 62 and a control substrate 63 are arranged inside of the housing 64 and the cover 65 in a laminated structure.

Abstract: In an electric motor-driven power steering apparatus which comprises a bridge circuit for connecting a power source between input terminals and also connecting an electric motor between output terminals and energizes the electric motor by this bridge circuit and operates electric motor power to a steering system, the bridge circuit includes a predetermined number of arms constructed by connecting circuits for connecting switching elements in parallel with diodes in series so that the diodes mutually become reverse polarity.

Abstract: An electronic triggering device for a two-motor wiper system with two electric motors is proposed, in which the triggering device includes a parallel circuit of three half bridges; one of the three half bridges intended for triggering both electric motors in common. A method for triggering such a triggering device is also proposed.

Abstract: A motor control circuit includes a forward rotation control circuit, a reverse rotation control circuit, and a brake control circuit. The forward rotation control circuit allows a first current source to supply a first current signal to a motor drive circuit for operating a motor in a forward rotation mode. The reverse rotation control circuit allows a third current source to supply a third current signal to the motor drive circuit for operating the motor in a reverse rotation mode. The brake control circuit allows a second current source and a fourth current source to respectively supply a second current signal and a fourth current signal to the motor drive circuit for operating the motor in a brake mode. The motor control circuit reduces power dissipation in the brake mode since the second and fourth current signals may be smaller than the first and third current signals.

Abstract: A moving body drive control device characterized by mutually balancing a magnitude of driving force TK and a magnitude of braking force TB, both of the forces being generated by a motor, to approximate a moving speed of a moving body 100 to a target speed highly precisely without being affected by a disturbance and the like in a state where the drive control device always applies at least any force of the driving force TK and the braking force TB to the moving body 100 to always apply a driving load thereto.

Abstract: An electric power steering apparatus includes a steering torque detector, a brushless motor PWM-driven with a three-phase alternating motor current, a target current setting section for setting a d-axis target current value and a q-axis target current value, motor current detectors for detecting motor current values supplied to the brushless motor, a three-phase AC/d-q coordinate transformation circuit, a first deviation calculation circuit for calculating a deviation of a current value of a q-axis detection signal from the q-axis target current value, a second deviation calculation circuit for calculating a deviation of a direct current value a d-axis detection current signal from the d-axis target current, a motor control section for controlling driving of the brushless motor through a vector control process on the basis of deviation signals outputted from the first and second deviation calculation circuits, and an attenuation device provided in a feedback transmission path of the q-axis detection current s

Abstract: A method of operation for a motor-driven worm gear actuator coupled to a load device energizes the motor in a series of pulses during an initial period of motor operation when reversal of the motor is commanded. The pulsed energization produces a slow initial axial movement of the motor armature without moving the load device, minimizing the contact force between the armature shaft and a mechanical end stop of the motor. Rotation of the motor is determined by identifying and counting motor current pulses due to commutation, and the pulse count is adjusted at each reversal of motor rotation to compensate for motor current pulses due to the pulsed energization.

Abstract: In the prior art electric power steering controller, if it is restarted immediately after being turned off, melting and welding of a contact of a relay are detected while a smoothing capacitor is not yet fully discharged. This may lead to a misdetection. A novel electric power steering controller has a relay contact voltage detection circuit and a discharging circuit. The relay contact voltage detection circuit is located between the battery of a vehicle and an electric motor to give an assisting torque to a steering wheel and acts to detect the voltage at the contact of a relay on the side of the electric motor, the relay controlling the output from the battery. Then, melting and welding of the relay contact are detected, based on the voltage at the relay contact detected by the relay contact voltage detection circuit.

Abstract: A half-bridge gate driver circuit including two separate floating high-side driver circuits for operating a switch circuit having a high-side switch and a low-side switch. Each of the driver circuits include input control logic which is referenced to a supply signal with a potential that becomes negative relative to the negative common terminal of the switches, thereby enhancing the operation of the switch circuit. The circuit may further include signal translation stages for translating control signals to the control logic of the driver circuits. The signal translation stages include a plurality of cascoded parasitic transistors which provide a neutralizing capacitance to minimize noise.

Abstract: A drive circuit 12 is mounted on a metal substrate 50, a control circuit 13 is mounted on an insulating substrate 70, and a large current circuit component such as an electrolytic condenser 18 is mounted on a baseboard 30 integrated with a metallic circuit conductor constituent member 31 by insert molding, in which the metal substrate 50 and the insulating substrate 70 are laminated on the baseboard 30.

Abstract: A driving circuit for a voice coil motor (VCM) includes a full bridge output stage for driving the motor in a pulse width modulated (PWM) mode. A multiplexer having two inputs is coupled to respective output nodes of the full bridge output stage, with one of the output nodes providing a back electromotive force induced in the motor upon setting in a high impedance state the full bridge output stage and conducting at least one transistor connected to ground in the full bridge output stage after current through the motor has decayed to zero. A controller compares a voltage representing a desired speed of the motor with the back electromotive force, and generates a correction signal based upon the comparison.

Abstract: In an electric power assisted steering system a power stage (2) is provided comprising at least a first conducting means (4), and a control stage (1) is provided comprising a second separate conducting means (5) adapted to carry one or more electrical components of a control circuit. Each conducting means comprising one or more conductive tracks or links (10) for carrying current to and/or from components of the electric power assisted steering system.

Abstract: A micro-motor position controller utilizes a ratiometric position sensor that operates independent of any reference voltage sources. A first capacitor and a second capacitor in a micro-motor are connected in series and form one section of a capacitive bridge. The other section of the bridge is ground. A first sinusoidal voltage is created at the top of the capacitive bridge and a second sinusoidal voltage that is 180 degrees out of phase from the first sinusoidal voltage is created at the bottom of the bridge. The motor is moved and the capacitance values of the first and second capacitors are changed until, ultimately, there is no voltage present on the armature of the motor. The voltage level present at the armature is measured relative to AC ground, and is used as an error signal to control the position of the motor.

Abstract: Method of controlling a motorized door by offloading the burden to a separate motion control processor. The method includes generating, in a central processor for the door, one or more signals indicative of a predetermined door speed profile for a stroke of the door. The predetermined door speed profile provides an ideal velocity versus an elapsed time since a beginning of the stroke. The signals are communicated to a motion control processor and the motion control processor also receives door position signals from a position encoder. The motion control processor generates signals indicative of the velocity of the door based on the door position signals and it generates error signals based on discrepancies between the velocity of the door and the ideal velocity. It generates motor control signals based on the error signals and the motor control signals are communicated to the motor of the door.

Abstract: An actuator position control system for brush-type DC motors. The system includes a sensing inductor, amplifier, central control unit (microprocessor), and motor driver. The system utilizes the differential signal di/dt to indicate the falling edges of commutation spikes in the motor current profile. An inductor is selected as the signal sensor, because voltage drops across the inductor are directly proportional to di/dt. The voltage drop, L(di/dt), across the inductive sensor is input to the amplifier, amplified, and then sent to the microprocessor. The microprocessor reads the output pulses from the amplifier and compares the pulse count to an input command signal. The microprocessor then sends shaft position control information to the motor driver.

Abstract: When an electromagnetic relay connects a movable contact to a normally open contact N/O, direct current flows through direct current motor and thereby the direct current motor is driven. When the electromagnetic relay connects the movable contact to a normally closed contact N/C, the rotation of the direct current motor is braked. A plurality of normally open contacts N/O are connected in series in the passage of direct current obtained when the electromagnetic relay connects the movable contact to the normally open contact N/O.

Abstract: In order to brake a brushless motor in a forward rotation to give a reverse rotation force, source-side and sink-side transistors for supplying driving circuits *a, *b, *c, *d, *e, *f are periodically switched on and switched off based on the oscillation frequency of an oscillator (13) when a both end voltage of a current detection resistance (10) is higher than a reference voltage Vref. Moreover, the transistors are kept in an ON state all the time when the both end voltage of the current detection resistance (1) has lowered below the reference voltage Vref. With this arrangement, damage to a source-side transistor due to a large current flowing thereinto when the motor rotating in a reverse direction can be prevented.

Abstract: One terminal 3a of the DC motor 3 is connected to the power supply terminal 301, and the other terminal 3b of the DC motor 3 is connected to the ground terminal 302 through the FET 1. The FET 2 is connected between the terminal 3a and terminal 3b of the DC motor 3. A reversal input terminal of the comparator 6 is connected to the terminal 3a of the DC motor 3, and a non-reversal input terminal of the comparator 6 is connected to the terminal 3b of the DC motor 3. The output terminal of the comparator 6 is connected to the gate of the FET 2 through the switch SW1. The CPU 200 supplies a control signal FV which is changed at a predetermined period T according to the speed signal supplied from the receiver 100, to the gate of the FET 2 through the driver 7. When the counter electromotive force is generated in the DC motor 3, the comparator 6 supplies a high level control signal RD to the gate of the FET 2 through the switch SW1.

Abstract: In order to make an electric motor smooth in drive with improving the electric consumption efficiency, the over heat of a motor driver and vibrations thereat are restricted which result from chopping energization of the electric motor.

Abstract: The present invention is an electronic lock having a shorting or shunt circuit designed to allow an authorized operator to open the electronic lock and which will prevent an unauthorized operator from opening the lock when authorized combination has not been entered.

Abstract: A retractor device for the LCD unit of an on-board entertainment unit is disclosed. The retractor device uses capacitors as storage device to provide electrical energy to drive the retractor motor in the reverse direction in the event of power outage. Under normal operating conditions, the deployment and retraction of the LCD is performed by the motor, with its polarity switched by a relay. At the same time, a storage capacitor is charged up. In the event of power outage while the LCD is in a deployed mode, the energy stored by the capacitor is discharged to drive the motor's retraction mechanism. Blocking diodes may be used on the discharge path to ensure that the discharge path goes toward the motor.

Abstract: A circuit (40) and method for applying drive voltages to a voice coil motor (VCM) (22) of a mass data storage device (10) has two driver sets, each having a high side driver (HSD) (42,46) and a low side driver (LSD) (44,48) connected to the VCM (22). Each driver set has two SENSEFETs (50,52), each having a power FET and a sense FET. A circuit (106,104) is provided for sensing a sense current in the sense FET of the LSD, and a circuit (60,76,74) is provided for increasing the bias on the gates of the SENSEFET (52) in the LSD when the sense current falls below a predetermined level (VREF). Also, a circuit (113,114,110) is provided for driving a predetermined current in the SENSEFET of the HSD when the sense current falls below the predetermined level. Thus, a current at the predetermined level always flows in the SENSEFETs (50,52).

Abstract: An automatic door control system which uses microcontrollers to control four drive transistors and a drive motor connected in an H-bridge circuit. The microcontrollers use pulse width modulation to control the speed of the drive motor.

Abstract: A sunroof controlling device for controlling a sunroof lid in sliding and tilting directions without using a mechanical position switch, which comprises and actuator having an electric motor and an output shaft to be connected with the sunroof lid, a switch for generating a command signal, and a control unit including an armature shaft rotation signal generating means, an output shaft rotation signal generating means, and a counting means for counting the signals generated from the armature shaft rotation signal generating means and the output shaft rotation signal generating means, and the control unit starts current supply to the electric motor of the actuator in response to the command signal and interrupts the current supply according to the count value of the counting means.

Abstract: A motor drive circuit is comprised of an H-bridge circuit which is formed of a flywheel diode and a switching device and connected to a motor coil; a current detecting circuit which is connected to the H-bridge circuit, has a plurality of shunt resistors, and computes a motor coil current value on the basis of voltage drops in the shunt resistors; a memory for storing an energizing direction of the motor coil and command value data regarding an energizing current waveform; a control circuit issues energizing current amount of the motor coil so that an error between command value data stored in the memory and a detected current signal detected by the current detecting circuit always stays zero; and a switching device driving logic circuit switches both source and sink of the H-bridge circuit when the motor coil is excited.

Abstract: A permanent magnetically excited electrical rotary drive for a blood pump is proposed, comprising a permanent magnetic rotor and a stator, said stator comprising a drive winding having at least two loops for the production of a magnetic drive field which produces a torque on the rotor, with each loop belonging to a different electrical phase, furthermore comprising a setting device which supplies each loop in each case with a phase current or in each case with a phase voltage as a setting parameter, with the setting device comprising a separate power amplifier for each loop so that the setting parameter for each loop can be regulated independently of the setting parameter for the other loops.

Abstract: A DSP of a servo control circuit obtains a movement value of a servomotor for each axis for each position-speed feedback processing cycle in accordance with a move command value for each axis delivered from a main processor with every distribution cycle, and also obtains a position correction value in accordance with pressure information detected by a sensor. The DSP of the servo control circuit carries out position-speed feedback processing with the use of a move command value which is obtained by correcting the movement value with the obtained position correction value, and drives the servomotor.

Abstract: An improved motor commutation pulse detection circuit for comparing a filtered motor current signal to a threshold value, where the circuit is responsive to the actual or expected amplitude of the commutation pulses for adjusting the motor current signal or the threshold value so that the compared threshold value is substantially equal in amplitude to minimum amplitude commutation pulses in the compared motor current signal. In one circuit, the threshold value is varied in accordance with the average current flowing through the motor at the time of the commutation event. In another circuit, the threshold is effectively switched between a high value and a low value depending on the mode of operation of the motor. A motor run detection threshold is activated during motor running periods, while a motor brake detection threshold is activated during motor braking.

Abstract: The present invention relates to an electronic circuit that interrupts the application of electrical power to a motor after a predetermined period of time. The electronic circuit is disposed between a motor which drives a device from an initial position to a final position and a switch movable from a first position to a second position. A battery which supplies the electrical power for the motor is engaged with the switch. The control circuit includes at least two energy storage devices. Depending on the position of the switch, one of the energy storage devices will be fully charged by the battery source. Altering the position of the switch will cause the fully charged energy storage device to begin its discharge and the alternate energy storage device will be “instantly” charged. During the time that both energy storage devices have a significant charge on them, a control signal is generated.

Abstract: A power window regulator is disclosed comprising a regulator computer having a processor and a memory connected to a switch and/or main automotive computer and to a plurality of window processors connected to a window sensor and a window drive unit.

Abstract: A multi-channel motor winding configuration providing low harmonic distortion and a PWM inverting controller for this type of winding configuration are disclosed. The motor winding configuration includes a plurality of individually insulated conductors wound in a group through the stator slots of a synchronous or induction type alternating current (AC) motor. Depending on the winding configuration, the group of conductors may constitute a portion of or the entire current carried by one phase of a single or polyphase motor. The PWM controller for this type of winding configuration connects each conductor in the group to its own dedicated set of power switching devices in an H-bridge configuration. The H-bridge configuration is powered by a direct current (DC) or rectified AC source.

Abstract: An actuator circuit includes an H-bridge having sense and power FETs to drive a voice coil motor. A differential amplifier configuration is connected to the H-bridge. A bias circuit connected to the H-bridge and to current sources controls bias current through the one sense FET and one power FET and through the other sense FET and other power FET. A common mode feedback is circuit connected to the voice coil motor to provide common mode feedback to the differential amplifier configuration. The FETs, which may be unmatched, are operated to achieve class AB operation.

Abstract: A power-driven disc storage case comprising an outer casing, a chassis, a rolling top, a plurality of disc brackets, two button switches, a micro high-speed D.C. motor, a transmission with safety protect mechanism, a main switch, and two lamps. Two discs are vertically provided on each of the disc brackets. A rolling top is opened and then the lamps installed inside are turned on so as to illuminate the disc at the front opening. The user can select a disc, press down the button switches (left or right) if it is not the target disc to be chosen by the user. The motor then drives the chain of the brackets to move the discs either left or right. The user does not release the push-button switch until a disc needed has moved to the front opening and takes out the disc.

Abstract: A contactorless multi-motor controller is described which comprises a contactorless pump motor starter and a contactorless, reversible traction motor controller. The two controllers are mutually interactive. When the pump motor has ramped up to full voltage, a function block on-board said pump motor control circuit detects this condition and enables the tramming operation of the traction motor.

Abstract: A travel-limit circuit having a DC motor for a lens by which the endurance of the motor can be improved while at the same reducing the rebound due to the inertia of the moving body at a travel extremity. The travel-limit circuit has a lens motor that drives, e.g., zoom lens groups. Limits which detect whether the lens group has reached their travel extremities at which mechanical stoppers are provided. The motor driving circuit, which drives the lens motor and the limit switches, activates a short break by short circuiting the pair of input terminals on the lens motor via diodes while cutting current flow from the motor driving circuit for the lens motor upon detection that the lens groups have reached their travel limit.

Abstract: A sensorless motor driver receives the back electromotive forces appearing in the individual coils provided one for each phase in a brushless motor and the voltage at the node common to all of those coils, and produces square-wave signals including noise. These signals are then subjected to masking by a masking circuit in accordance with a noise masking signal produced by a masking signal producing circuit. In accordance with the thus masked signals, a driving current is supplied to the brushless motor. The driving current varies according to the load on the motor. The masking signal producing circuit monitors the driving current supplied to the motor, and outputs the masking signal in such a way that the length of the masking periods varies according to the driving current.

Abstract: A method and circuit for controlling a motor and reducing and/or eliminating mid-velocity instability in the motor are provided. The method includes the step of receiving a decay time indicative signal that is indicative of the current decay time in a phase coil of the motor after current commutation. The decay time indicative signal assumes a first polarity proportional to the current decay time in the phase coil. The method further includes the step of calculating a delay time corresponding to the amount of time the decay time indicative signal has the first polarity. Finally, the method includes the step of controlling the direction of current in the phase coil or another phase coil of the motor responsive to the delay time and a current direction signal generated by a translator. The inventive method and circuit enable reduction and/or elimination of mid-velocity instability even when the motor is operated in a microstepping mode.

Abstract: An electric power steering circuit assembly comprises a heat sink, a power circuit board secured in close contact with the heat sink, mounted with large-current parts, and having connecting members erected thereon, a housing mounted with large parts and secured to the heat sink so as to cover the power circuit board, a control circuit board mounted with control components and secured to the housing so as to overlap the power circuit board in the vertical direction, and guides disposed on the housing for receiving the connecting members to position the housing relative to the power circuit board.

Abstract: Circuitry (100, 100') for determining actuator position includes four MOS transistors (T1-T4) connected to each side of a bi-directional motor (10). The current flowing through the motor (10) at any given time is proportional to voltages developed across the internal impedances of the transistors (T1-T4). The resulting motor voltages are amplified and high-pass filtered to remove any DC offsets due to the signal amplification. The conditioned motor voltages are then compared to one or more threshold voltages and passed through a one shot circuit (120) to provide detectable pulses for each motor commutation event. Circuitry (106,107) is provided for counting pulses provided by the one shot circuit (120) and, based on a desired motor position, for providing a number of digital control signals to a digital control circuit (104).