Abstract: A power assist wheelchair includes a wheel, an electric motor that drives the wheel, an encoder that detects rotation of the electric motor, and a control device that controls the electric motor. The control device includes a total torque value calculator that calculates a total torque value based upon only a detection signal of the encoder, an assist torque value calculator that calculates an assist torque value based upon an output current of the electric motor, a manual torque value calculator that calculates a manual torque value based upon a difference obtained by subtracting the assist torque value from the total torque value, and a target current determiner that determines a target current of the electric motor based upon the manual torque value.

Abstract: A controller for operative connection to a power assisted transport vehicle that is at least partially directed by a human operator in physical contact with the vehicle, the controller including: a contact surface with a deadman switch, a first sensor and a second sensor each responsive to manual actuation of the contact surface, each sensor having a respective first sensor output signal and a second sensor output signal, and a signal processing means adapted to process the first and second output signals, and control the mode of operation of the controller in accordance with the state of the deadman switch.

Abstract: A service apparatus for use in maintaining a turbine assembly (100) includes a carriage (132, 304) configured to move through a cavity of the turbine assembly (100), a motorized system (218, 500, 600, 700, 800) coupled to the carriage (132, 304), and a maintenance device (128, 400) coupled to the motorized system (218, 500, 600, 700, 800). The motorized system (218, 500, 600, 700, 800) is configured to move the maintenance device (128, 400) relative to the carriage (132, 304). The motorized system (218, 500, 600, 700, 800) includes a first motor (710, 720, 805) configured to move the maintenance device (128, 400) in a first direction (324) and a second motor (710, 720, 805) configured to move the maintenance device (128, 400) in a second direction (324).

Abstract: A control apparatus for a multi-phase rotating electric machine includes at least one electric power converter, a command value calculator and an input voltage determiner. The at least one electric power converter converts DC power into multi-phase AC power and supplies the multi-phase AC power to the rotating electric machine. The command value calculator calculates command values for operating the at least one electric power converter. The input voltage determiner determines whether an input voltage of the at least one electric power converter is within a normal operation range. When the input voltage is determined by the input voltage determiner to be outside the normal operation range, the control apparatus switches control to ignore voltage change or current change caused by the reverse input of an external force to the rotating electric machine from a load side or suppress control fluctuation caused by the reverse input of the external force.

Abstract: Pulley-movement detection within an alternator or integrated starter/generator (ISG) for a vehicle is provided. The alternator or ISG includes a housing, a stator fixed within the housing, a rotor configured to rotate relative to the stator about an axis, and a shaft coupled to the rotor for rotation about the axis. The alternator or ISG also includes pulley coupled to the shaft at an interface, and configured to engage with a chain or belt to transfer movement between the shaft and the chain or belt. An electrical switch located at the interface is configured to be in a first state when the pulley is axially secured to the shaft, and a second state when the pulley is axially displaced away from the shaft. This can enable signals or warnings to be output in response to the electrical switch changing states, indicating an improper connection at the interface.

Abstract: An inverter device according to an embodiment includes a plurality of switching elements and processing circuitry. The switching elements are connected to each other in parallel, and each of them includes a transistor and a free wheeling diode connected to the transistor in antiparallel. The processing circuitry is configured to monitor a current flowing through the free wheeling diode included in each switching element or a temperature of the free wheeling diode and to control, in accordance with the current or the temperature, a load on each free wheeling diode to prevent unbalance of loads between free wheeling diodes in the switching elements.

Abstract: In an electric power steering system, a motor outputs, based on an AC voltage controlled by switching elements using a power-supply voltage from a power source, assist torque for assisting a driver's turning effort of a steering member. A voltage monitor monitors the power-supply voltage, and a determiner determines whether the power-supply voltage is lower than an assistive voltage. The assistive voltage is defined as a voltage that enables the motor to output the assist torque. A temperature detector detects a temperature of each switching element. A motor control unit determines whether the temperature of each switching element is lower than a heat-resistant temperature of the corresponding switching element. The motor control unit controls a motor current when it is determined that the power-supply voltage is lower than the assistive voltage, and the temperature of at least one switching element is lower than the heat-resistant temperature.

Abstract: An electrically power assisted wheelchair includes a hand rim, a wheel that is rotated by receiving a torque applied to the hand rim, and a drive controller configured or programmed to apply auxiliary power to the wheel based on the torque applied to the hand rim. The drive controller is configured or programmed to decelerate rotation of the wheel when the wheel is rotating and no torque is applied to the hand rim in a brake mode in which a brake torque acting in a direction reverse to a rotation direction of the wheel is applied to the wheel.

Abstract: A semiconductor substrate is provided with a first cell region, the first cell region including: an n-type emitter region; a p-type first top body region; an n-type first barrier region; an n-type first pillar region; and a p-type first bottom body region, the semiconductor substrate may further comprise: an n-type drift region; a p-type collector region; an n-type cathode region, the n-type first barrier region may include a first peak position where a peak of the n-type impurity density is present within a part linked to the n-type first pillar region, and a second peak position where a peak of the n-type impurity density is present within a part in contact with the gate insulating layer, and a depth of the first peak position from a front surface of the semiconductor substrate is different from a depth of the second peak position from the front surface of the semiconductor substrate.

Abstract: An electric power steering apparatus includes a shunt resistor connected to an inverter, a controlling motor current detection circuit connected to two terminals of the shunt resistor in a positive direction, which detects phase currents of a motor and uses the detected phase current as a controlling motor current detection value of assist control, and a diagnostic motor current detection circuit that is connected to two terminals of the shunt resistor in an opposite direction and detects a failure of the controlling motor current detection circuit. Each phase current of the motor is detected by one-shunt type and the assist control is performed, and two systems of a circuit for amplifying a voltage between two terminals of the shunt resistor are provided.

Abstract: Systems and methods for monitoring partial discharge within a remotely located and inaccessible electric motor. One embodiment comprises a downhole electric motor of an electric submersible pump system positioned in a well. The motor includes a partial discharge monitoring system coupled to the motor's power terminals. The partial discharge monitoring system includes a filter subsystem, a processing subsystem, and a communication subsystem. The filter subsystem allows higher frequency signals to pass from the terminals to the processing subsystem. The processing subsystem identifies signal constituents that are associated with partial discharge, and may perform various types of processing or analysis of the signal received from the processing subsystem. The partial discharge information generated by the processing subsystem is passed to the communication subsystem, which communicates the information to remotely located surface equipment.

Abstract: An electrically driven mooring winch is provided. The mooring winch includes a winding drum, an AC motor configured to drive the winding drum, a frequency conversion unit connected to the AC motor, and a control unit configured to control the frequency conversion unit on the basis of an indicator for tension of the mooring rope. The control unit is configured to set a reference value of rotational speed of the AC motor to a predetermined value, drive the AC motor in one direction for a predetermined time interval, define a first value of a torque of the AC motor, drive the AC motor in an opposite direction for the predetermined interval, define a second value of the torque of the AC motor, and compute a torque estimate using the first and second values of the torque.

Abstract: A PCU drives a motor generator using electric power from a power storage device. The PCU includes a power conversion device, a capacitor and a control unit. When detecting a crash, the control unit drives the power conversion device and discharges charges remaining in the capacitor. Each of a plurality of reverse conducting-type semiconductor elements included in the power conversion device is integrally formed of a first semiconductor element operating as a switching element and a second semiconductor element operating as a free wheeling diode. In response to detection of the crash of a vehicle, the control unit changes a voltage applied to a gate terminal of the first semiconductor element and increases an electric power loss during a current-circulating operation by the second semiconductor element. As a result, the remaining charges stored in the capacitor in the drive apparatus is discharged as soon as possible.

Abstract: An electrically driven mooring includes a winding drum (101), an alternating current motor (103) arranged to drive the winding drum, a frequency conversion unit (104) connected to the alternating current motor, and a control unit (105) arranged to control the frequency conversion unit on the basis of an indicator for tension of the mooring rope. The control unit is arranged to compute a flux space vector for modelling a stator flux of the alternating current motor, to compute a torque estimate on the basis of the flux space vector and a space vector of stator currents, and to use the torque estimate as the indicator for the tension of the mooring rope. Hence, a need for a force sensor on the mooring rope and a need for a speed/position sensor on the motor shaft can be avoided.

Abstract: Certain exemplary embodiments comprise a method that can comprise, via a device that originates sub-harmonic vibrations, applying a vibration treatment, to a rotor of an electric motor for a predetermined time period. The rotor can be thermally sensitive. The vibration treatment can be adapted to reduce internal stresses in the rotor, thereby reducing a vibration level of the rotor.

Abstract: A system and a method for adjusting a dead-time interval between de-activating a first transistor and activating a second transistor in a motor control circuit are provided. The method includes determining a plurality of commanded torque values associated with a motor based on a received signal over time. The method further includes setting the dead-time interval value equal to a first value when one commanded torque value of the plurality of commanded torque values is within a first torque range. The method further includes decreasing the dead-time interval value as other commanded torque values of the plurality of commanded torque values increase over time within a second torque range. The second torque range is greater than the first torque range. The dead-time interval value is indicative of a desired dead-time interval.

Abstract: A steering device for a motor vehicle comprises a stationary skeleton which has an essentially arc-shaped skeleton section, and an actuation member that is movably mounted on the skeleton section and that has two contact sections essentially opposite from each other. The actuation member surrounds the skeleton section with a ring-shaped cross section and extends between the contact sections continuously along the arc-shaped skeleton section.

Abstract: A method for controlling a vehicle seat adjuster in an adjusting path having a first mechanical stop and a second mechanical stop. A user sets an adjustment position of the adjuster inside the adjusting path. A protective stop is also automatically set in the adjusting path in the vicinity of the mechanical stops or another mechanical block blocking the adjusting path. The protective stop causes the adjusting motion to be reduced or stopped upon reaching of the protective stop. This helps produce a smooth braking of the vehicle seat and reduces the mechanical strain on the mechanical stops. The protective stop may be corrected with an updated protective stop. The updated protective stop is maintained despite any user action if a condition dependent on the adjusting motion of the adjuster is fulfilled. Learning regions within the adjusting path are provided to allow the setting of updated protective stops within the learning regions.

Abstract: Several embodiments of electric power assisted manually operated devices wherein the manual input force is sensed by a sensor that does not require lost motion connections and significant movement in order to determine the force applied. Also a compact drive is disclosed that permits the application to winding drums such as fishing reels. In addition a simplified temperature compensation system for the sensor is employed. Thus, the arrangements can be easily utilized with conventional structures with minimum change.

Abstract: An electric power system having an electric motor, a speed-reduction mechanism, a power board on which components generating heat are mounted, a control board on which components generating little heat are mounted, a circuit case, and a heat sink for dissipating heat from the power board. A conductive board for wiring is insert-molded in the circuit case. The power board is brought into intimate contact with the heat sink. The circuit case is mounted to the heat sink so as to cover the power board. The control board is mounted to the circuit case. The power board, the circuit case, and the control board are stacked on top of each other in this order to constitute a controller. The motor is mounted to the heat sink by support members. The heat sink is mounted to the speed-reduction mechanism.

Abstract: A force-responsive sensor is disclosed, such as for incorporation in a safety system for detecting an obstruction in a window opening closable by a motorized slidable window pane. The sensor is mounted within a hollow volume in flexible material running alongside the top frame member of the window opening. The sensor comprises an upper flexible and resilient layer supporting a continuous longitudinally extending conductive strip. This upper layer is spaced from a similar layer supporting a continuous longitudinally extending conductive strip, the two layers being separated from each other by insulating spacers spaced at intervals along the length of the sensor. Any obstruction in the window opening is carried upwardly by the rising window glass and applies a force to the flexible material. A ridge in the lower wall of the hollow chamber responds by causing contact between the two conductive strips to produce a warning signal.

Abstract: An object detection system includes a sensor in communication with a controller which identifies contact with the sensor. In a preferred embodiment the sensor is a piezo film which generates a signal when an object applies a predetermined force to the edge of the moveable glass member. This signal is identifiable by the controller in communication with the piezo film. Another embodiment of the sensor provides a pair of substantially parallel segments of conductive material applied along the edge of the window. When an object is in contact with both segments of conductive material an electrical signal is conducted and identified by the controller. When the controller determines an object is in contact with the sensor and therefore the moveable glass member, the controller halts or reverses the movement of the moveable glass member to prevent trapping the object between the closing moveable glass member and the frame.

Abstract: An electric assist steering system (10) includes a torque sensor (16) that provides an applied torque signal (24) indicative of applied steering torque. A motor position sensor (36) provides a motor position signal (40) indicative of the relative position between the rotor and the stator of an AC permanent magnet electric assist motor (22). A first controller (26) controls energization of the electric assist motor and a second controller (54) calculates a DQ vector value in response to applied steering torque and motor position. The second controller (54) also transforms the monitored motor current and position into DQ values. The second controller (54) compares the DQ values responsive to applied steering torque with the DQ value from monitored motor current and position. The electric assist motor (22) is disabled if the comparison indicates inconsistent results.

Abstract: The controller possesses a reference torque signal setting unit which generates a reference signal which becomes high when the detected signal becomes high based on at least the signal detected from the steering torque sensor; a correction torque signal setting unit which generates a correction torque signal (DN*RT*RV), which becomes high when the detected signal becomes high based on at least the signals detected from the revolution number sensor for the electric motor and from the vehicle speed sensor; and a target torque signal calculator which subtracts the correction torque signal from the reference torque signal (DN*RT*RV) to output a target torque signal (DT+−DN*RT*RV) to the electric motor; and the controller also making the correction torque signal high when failure of the vehicle speed sensor is detected.

Abstract: To keep low the cross frequency of current feedback control and provide a good steering feeling, a first operation expression is selected when a difference &xgr; between a current instruction value computed based on a steering state of a steering wheel and a traveling state of a vehicle and a motor drive current value supplied from a battery to a motor for providing assist force to a system for transmitting power from the steering wheel to the wheels is larger than a predetermined value Th1, a second operation expression is selected when the difference &xgr; is smaller than the predetermined value Th1, and the difference &xgr; is corrected using the selected operation expression.

Abstract: An obstruction detection apparatus is provided for use in closing a power driven vent, such as a window, that is located in an opening. When the vent includes a first closing edge that moves as the vent is closed and the opening includes a second closing edge that is contacted by the first closing edge when the vent is in a fully closed position, the apparatus includes a detector configured to detect an obstruction at points all along the second closing edge without requiring contact between the obstruction and the vent and to deliver a detection signal when an obstruction is detected. A controller is connected to the detector for receiving the detection signal and delivering a corresponding alarm signal.

Abstract: A steering device for a motor vehicle is proposed, with an actuating member to introduce a steering movement and with a steering linkage to transfer the steering movement to the wheels.The steering device is characterized according to the invention in that the actuating member consists of a non-rotatable "steering wheel" (1), in the rim (2) of which a band-shaped or chain-like actuating ring (3), movable relative to the rim (2), and a measured value transmitter (4) for generating an electrical or electronic position signal for the actuating ring (3) are arranged, and that the steering linkage is actuated by an adjustment drive which is controllable by an electrical or electronic regulating device as a function of the position signal.

Abstract: An awning, in particular an awning with a supporting arm, the cloth (1) of which can be unwound from a tube or winding shaft (2) driven by an electric motor (9) and in which are provided means for measuring the drive torque which supply a variable representing the windforce acting on the awning cloth. The measuring means are associated with a logical processing unit (15) in which are recorded three torque values, namely a danger, a safety and an all-clear value, on the basis of which values the LPU allows or activates the partial or complete unwinding or winding of the cloth.

Abstract: To provide a controller of an electric power-steering system, capable of improving the steering performance by presuming a motor angular speed .omega. in a range in which the angular speed of a motor is small and moreover very accurately presuming the motor angular speed and thereby, completely showing the functions for compensating the inertia of the motor and controlling the astringency of a vehicle. Because the presumed error of a back electromotive force between a model motor and a motor to be actually mounted is proportional to a motor current, a dead zone of a motor angular speed having a width proportional to a motor current is set to the presumed value of the motor angular speed. When the motor current is small, the width of the dead zone also decreases. Therefore, it is possible to presume an angular speed .omega. even in a region where the motor angular speed is small.

Abstract: A power closure panel control apparatus is independent of closure panel configuration and capable of a diverse range of remote and direct activation. Sophisticated safety features utilize an adaptive strategy to facilitate highly sensitive obstruction detection by learning the closure system's force requirement and applying a safety margin to it. The control system allows the closure panel to operate in a totally manual mode.

Abstract: A stator 3 of a motor 1 is pivotally supported on a stationary system 5 by an elastic member 28, 11a, 42 provided along the circumferential direction of the stator 3, and a detector 11 for detecting a rotational force of the stator 3 is provided to execute the control of stopping, accelerating, decelerating or reversing the operation of the motor 1 based on a detection signal from the detector 11. When the motor load is increased, transmission of torque from the action system 3 to the reaction system 4 of the motor 1 is cut off, and consequently the stator 3 itself of the motor 1 pivots with respect to the stationary system 5 as a reaction. In this stage, the detector 11 detects the rotational force of the stator 3 to stop, accelerate, decelerate, or reverse the operation of the motor 1.

Abstract: A power-assisted wheelchair wherein the power-assist for the wheels is based upon the manual force exerted on both of the wheels. The power-assist is continued for a brief time period after manual power input is stopped. The continuing assist is provided equally to each wheel so that the wheelchair will coast in a straight direction. The wheels of the wheelchair are readily detachable with the backing plate prime mover and transmission for driving the wheel.

Abstract: A deformation detection system including an elongated element having a hollow deformable wall member that defines a radiation transmission path. A sound radiation transmission source positioned at one end of the elongated member transmits acoustical radiation into the radiation transmission path. A sound radiation detector positioned at an opposite end of the radiation transmission path is responsive to and detects the acoustical radiation transmitted from the radiation source. Deformation of the wall member at least partially interrupts the radiation transmission path such that transmitted acoustical radiation from the sound radiation source is attenuated, and the attenuated acoustical radiation is detected and assessed by the radiation detector. The detection system has particular applicability to monitor a body opening of a motor vehicle in which a closure member, such as a window, is movable towards a peripheral edge of the body to close the opening by an electrically operated drive mechanism.

Abstract: An apparatus and method that allows a user to exert a force to control a motive machine. The exerted force is transferred by a force transferring means to force sensors which detect the amount and direction in which the force is exerted. The force sensors convert the applied force into an electrical signal which is used to control the motive features of a machine.

Abstract: A method of controlling an electric power steering apparatus includes the steps of determining a steering state in accordance with a detection value and a retrieval value of a motor terminal across voltage, and limiting a motor current when a steering wheel held state is determined as the steering state determination result and a motor current value in the steering wheel held state is a predetermined value or more.

Abstract: First magnetic angular sensor outputs a sine-wave output and a cosine-wave output corresponding to positions of rotation of a rotary drum being fitted in a rotating drive shaft. Second magnetic angular sensor outputs a sine-wave output and a cosine-wave output corresponding to positions of rotation of another rotary drum being fitted on the rotating drive shaft. In case of the other output of the sine-wave output or the cosine-wave output of the first or the second magnetic angular sensor is varied while one output of the sine-wave output or the cosine-wave output in the first or the second magnetic angular sensor is not varied, the one output cosine-wave output or the sine-wave output of the first or the second magnetic angular sensor is determined to be a fault and an abnormality signal is delivered therefrom.

Abstract: In order to prevent a sudden kickback through the steering wheel which tends to occur when an electrically powered steering motor is de-energized and the vehicle tires are distorted by steering a low speeds and act as springs which cause the steering shaft to suddenly rotate in the reverse direction to that induced by the motor immediately before the de-energization, a circuit is provided which upon a manually operable switch which controls the power supply being moved to an open position, continues to supply a gradually decreasing level of power to the motor control circuit so that in the event that the driver is still applying a torque to the steering wheel, the motor produces a gradually reducing torque which allows the tire distortion to be relieved slowly and obviate any shock to the driver via the steering wheel.

Abstract: The present invention is a zoom motor control for controlling an electric motor for use in combination with an auto zoom device for a movie camera. The auto zoom device includes a rotating member driven by the electric motor and a zoom-lens tube rotating member. The zoom motor control includes a rectangular housing which an operator of the movie camera may comfortably hold in his hand and a strain gauge sensor which is mechanically coupled to the rectangular housing. The strain gauge sensor is disposed so that the operator may apply with his thumb a varying amount of pressure in either direction. The strain gauge sensor has an output signal which is proportional to the varying amount of pressure. The zoom motor control includes a control circuit for converting the output signal of the strain gauge sensor to a control signal for controlling the electric motor of the auto zoom device.

Abstract: A motor-operated brake system includes an input rod coupled to a brake pedal and displaceable with an axial thrust force commensurate with the depressing force on the brake pedal, a cylinder having at least one piston operable by the thrust force applied to the input rod for producing hydraulic pressure, the cylinder having a piston, a hydraulic pressure transmitting device for transmitting the hydraulic pressure generated by the cylinder to braking mechanisms associated respectively with wheels, a servo mechanism including an electric motor for producing rotational motion and a converting mechanism for converting the rotational motion from the electric motor to linear motion and transmitting the linear motion to the piston of the cylinder, the servo mechanism being arranged to apply an amplified force to the piston of the cylinder, a thrust detector for detecting the magnitude of the thrust force applied to the input rod, and a control device responsive to a signal from the thrust detector for generating a m

Abstract: An electronic controller for a therapeutic table with a shaft encoder for sensing the angular position of a movably mounted patient support and means for controlling the movement in accordance with a comparison between the sensed angular position and an angular limit reference. The left and right preselected tilt angles are alternately automatically selected as the reference. Fault conditions, such as a jam condition, occurs when the drive mechanism to briefly reverse to automatically correct the condition prior to power termination. In the event of excessive tilt, actuation of limit switches results in reversal and movement of the patient support to a horizontal position before power termination. The jam condition is sensed by a strain gauge for detecting the work required for movement of the patient support and comparing it to a preselected work reference. In the event of drive clutch disengagement, power to the motor is terminated.

Abstract: A vehicle power clutch system, whereby a clutch device is provided with a control lever designed to move between two operating positions, corresponding respectively to engagement and release, by virtue of an axially-mobile control member; at least a portion of the control member consisting of a screw connected, via the interposition of balls, to a nut screw integral with a hollow shaft on an electric motor, through which hollow shaft the control member itself extends; the electric motor being controlled by a threshold comparator, an input of which is connected to the electric output of a device for measuring axial tensile or compressive stress and located along the aforementioned control member.

Abstract: The present invention provides a controller for a power steering control system with a current limiter for limiting current to be fed to a power steering motor, in accordance with a power source voltage, whereby the power source is prevented from falling into an overdischarge state while a power steering function is performed. An additional feature of the present invention is an idle speed control device for increasing the engine idle speed when the current of the power steering motor reaches a predefined level.

Abstract: An electromagnetic servo unit is constituted with an outer casing (1), a first shaft (8) and a second shaft (5) both rotatably supported by the casing, an electric motor (101) built in the casing coaxially with the second shaft, the electric motor having an armature (10, 11) coaxially mounted on the second shaft, a torque detecting mechanism (8b, 22, 16, 21, 12) for detecting torque applied to either of the first and second shafts, and a control mechanism (21, 14, 15) for, receiving a detection signal from the torque detecting mechanism, controlling to start the electric motor. The torque detecting mechanism is arranged inside the casing, and the first and second shafts are mutually actuatably engaged with each other within the casing through the torque detecting mechanism. Preferably, the first and second shafts are coaxially supported by the casing, and have a relative angular displacement there between made use of for, when it is developed exceeding a predetermined angle range (.theta.

Abstract: An electric motor drive circuit (9; 209) in an electric power steering system (50) for vehicles includes a control mechanism (8, 9a) for producing a control signal (T.sub.2, T.sub.3, T.sub.4, T.sub.5) for controlling an electric motor (7) to produce auxiliary torque to be supplied to an output shaft (4), taking into consideration an output signal (S.sub.1, S.sub.2) from a steering torque detection mechanism (3) to detect steering torque (Ts) acting on an input shaft (1). The electric motor drive circuit (9; 209) is for controlling the electric motor (7) by receiving the control signal (T.sub.2, T.sub.3, T.sub.4, T.sub.5) from the control mechanism (8, 9a). The electric motor drive circuit (9; 209) comprises a bridge circuit (60) having between input terminals (61, 62) thereof an electric power (26) connected thereto and between output terminals (63, 64) thereof the electric motor (7) connected thereto.

Abstract: An electric power steering system (100) for vehicles includes a driving control circuit (50) adapted to generate a torque magnitude signal (Sa) and a torque direction signal (Sdr, Sdl), based on an output signal (VR, VL) from a torque detection mechanism (4, 9) for detecting the magnitude and the direction of steering torque acting on an input shaft (101) connected to a steering wheel (8), and to feed, to an electric motor (5) for supplying auxiliary torque to an output shaft (3) operatively interconnected with a steered ground wheel, an armature current (Io) of such a magnitude and in such a direction of conduction as desirous in accordance with both the torque magnitude signal (Sa) and the torque direction signal (Sdr, Sdl).

Abstract: An electric power steering apparatus causes a bridge circuit and a driver circuit to control normal and reverse rotation operations of a motor. The bridge circuit is constituted by transistors. The driver circuit is connected to a power source and also is connected to the bridge circuit so as to drive the bridge circuit. A diode is inserted between the power source and the bridge circuit, and the polarities of the diode are set such that a voltage at the bridge circuit is lower than that at the driver circuit.

Abstract: A motor-driven power booster suitable for use in a motor-driven power steering system. The power booster comprises a casing, input and output shafts rotatably supported on the casing, a first motor for driving the output shaft, a second motor for driving the input shaft, an angle detector operatively cooperating with the first and second shafts for generating an output signal dependent on angular positions of the input and output shafts, and an electric circuit for supplying electric power to the first motor to apply an output torque to the output shaft in response to the output signal from the angle detector and for supplying electric power to the second motor to apply a reactive torque to the input shaft in response to the electric power supplied to the first motor. Since the input and output shafts are mechanically uncoupled, desired output-torque vs. reactive-torque characteristics can easily be attained by the power booster.

Abstract: An electric motor driven power steering system is provided. The motor is prevented from operating at low torque command levels. After a first predetermined level of command torque is reached, the motor is controlled to generate torque at a predetermined rate less than the torque actually commanded by the vehicle driver. After a second predetermined level of commanded torque is reached, the motor is controlled to generate torque in accordance with the level of torque command. Thus, the phenomenon known as "hunting" and instability of the system at low torque levels are virtually eliminated. The system operates smoothly over its full range of operation and is not affected by rough road surface conditions.

Abstract: A power torque servo system (100) for roller swaging (122), including a servomotor (132) having a gear box (134) with a drive shaft (138). The motor is supported on two members (150, 152) on opposite sides of the drive shaft (138) and a third member (146) on which the motor may pivot. Strain gages (154, 156, 158, 160) are mounted on the members (150, 152) to measure servodrive reaction torque in the shaft when the shaft is rotated by the motor to function as a swage drive or in another torquing operation. There are switches (236) to set a final torque value to be obtained in the servo system and an electrical servo system for receiving the strain gage measurement signals to provide a smooth low speed approach to a final torque value (182) in the shaft (138) and to eliminate any dynamic torque overshoot in the shaft.

Abstract: An improved electric power steering system is disclosed. The system includes an electric motor as a driving device. Input system torque, motor current flow and motor temperature are detected and used to control the motor to prevent premature failure of the system due to elevated temperatures in the vehicle engine compartment.