Abstract: There is provided an electric motor controller for a steering device that can give an appropriate steering force to a steering wheel according to running conditions. An electric power steering controller of the present invention is provided with a steering shaft reaction force torque sensor for detecting a reaction force torque of a steering system, a superimposed reaction force torque calculating unit for multiplying a steering angle detected by the steering angle sensor by a gain-to calculate a superimposed reaction force torque in the return direction of a steering wheel and a control unit for controlling the gain such that the superimposed reaction force torque is reduced when a reaction force torque of the steering system is large and the superimposed reaction force torque is increased when a reaction force torque of the steering system is small.

Abstract: The present invention is an electric power steering apparatus which includes a multi-phase motor that assists steering effort of a driver, a motor drive circuit provided with at least an upper switching element that connects or disconnects the winding of each phase of the multi-phase motor and a power supply, and a lower switching element that connects or disconnects the winding of each phase of the multi-phase motor and grounding, a logic circuit that determines ON/OFF of the upper switching element and the lower switching element, and first and second microcontrollers that control the motor drive circuit via this logic circuit, in which the logic circuit determines ON/OFF of the upper switching element and the lower switching element so that the power to the winding of the each phase of the multi-phase motor is stopped according to the instruction of either the first microcontroller or the second microcontroller.

Abstract: In an abnormality detecting device for a position detecting device which generates an amplitude-modulated or phase-modulated signal from a position sensor according to the rotational position of the rotor of a motor when a reference signal having a predetermined periodic waveform is supplied, there are provided a bias current applying unit made of a passage including a resistance of applying DC bias current to an output winding of the position sensor, positional abnormality detecting units for detecting a biased DC signal of an amplitude-modulated or phase-modulated signal applied to the output winding apart from a position detector circuit for detecting the rotational position of the rotor, and an abnormality detection judgment processing part for judging abnormality of the position detecting device from a DC signal detected by the positional abnormality detecting units.

Abstract: An abnormality detection apparatus for a position detection device is provided which is capable of performing abnormality detection accurately and inexpensively. The position detection device has a primary winding and a secondary winding, and at least one excitation signal each having a predetermined periodic waveform is supplied to the primary winding to thereby generate at least one output signal each in the form of a phase modulated signal corresponding to a rotational position of a rotating member from the secondary winding directly or after having been subjected to phase shifting and appropriate arithmetic operations. The apparatus is provided with an abnormality detection section for determining an abnormality of the position detection device when the phase modulated signal has a peak value which is outside a predetermined range.

Abstract: A position detecting apparatus includes: a position sensor 10 that inputs an excitation signal having a given period waveform and outputs a first amplitude modified signal induced in accordance with a detected position from a first output winding and outputs a second amplitude modified signal induced in accordance with a detected position from a second output winding; a first phase shifting circuit 23 for electrically shifting a phase of the first amplitude modified signal by a given angle; a second phase shifting circuit 24 for electrically shifting a phase of the second amplitude modified signal by a given angle; converting means 15,16 for converting the signal outputted from the first phase shifting circuit 23 and the signal outputted from the second phase shifting circuit 24 into a phase modulated signal; and calculating means 17-22 for obtaining a detected position on the basis of the phase of the phase modulated signal outputted from the converting means 15,16.

Abstract: To provide an electric power steering apparatus capable of constructing a microcomputer redundant system that controls the motor with an extremely small amount of calculation and improving the reliability of the apparatus.

Abstract: A position detecting apparatus includes: a position sensor 10 that inputs an excitation signal having a given period waveform and outputs a first amplitude modified signal induced in accordance with a detected position from a first output winding and outputs a second amplitude modified signal induced in accordance with a detected position from a second output winding; a first phase shifting circuit 23 for electrically shifting a phase of the first amplitude modified signal by a given angle; a second phase shifting circuit 24 for electrically shifting a phase of the second amplitude modified signal by a given angle; converting means 15, 16 for converting the signal outputted from the first phase shifting circuit 23 and the signal outputted from the second phase shifting circuit 24 into a phase modulated signal; and calculating means 17-22 for obtaining a detected position on the basis of the phase of the phase modulated signal outputted from the converting means 15,16.

Abstract: An abnormality detection apparatus for a position detection device is provided which is capable of performing abnormality detection accurately and inexpensively. The position detection device has a primary winding and a secondary winding, and at least one excitation signal each having a predetermined periodic waveform is supplied to the primary winding to thereby generate at least one output signal each in the form of a phase modulated signal corresponding to a rotational position of a rotating member from the secondary winding directly or after having been subjected to phase shifting and appropriate arithmetic operations. The apparatus is provided with an abnormality detection section for determining an abnormality of the position detection device when the phase modulated signal has a peak value which is outside a predetermined range.

Abstract: To realize reliable detection of abnormality of a position detecting device regardless of a rotational position of a rotor, and attain simplification of a circuit structure and reduction of cost.

Abstract: There is provided an electric motor controller for a steering device that can give an appropriate steering force to a steering wheel according to running conditions. An electric power steering controller of the present invention is provided with a steering shaft reaction force torque sensor for detecting a reaction force torque of a steering system, a superimposed reaction force torque calculating unit for multiplying a steering angle detected by the steering angle sensor by a gain to calculate a superimposed reaction force torque in the return direction of a steering wheel and a control unit for controlling the gain such that the superimposed reaction force torque is reduced when a reaction force torque of the steering system is large and the superimposed reaction force torque is increased when a reaction force torque of the steering system is small.

Abstract: An antiskid brake controller, which can secure safety by avoiding a cascade caused when a braking pressure is reduced in a four-wheel-drive vehicle, includes wheel speed sensors braking force adjuster for adjusting a braking pressure and an ECU for calculating the control amount of a breaking force adjuster so as to prevent the locking tendency of each of the wheels based on a wheel speed Vw. The ECU includes means for the wheel deceleration calculator Gw corresponding to the locking tendency of each of the wheels, a basic vehicle calculator speed, a slip amount calculator SL based on the wheel speed Vw and the basic vehicle speed, cascade determination device for determining the occurrence of the cascade state when an unstable state occurs such that the slip amounts of three wheels are larger than a predetermined value and control amount corrector for changing the control amount of the braking pressure in an increasing pressure reduction amount when the occurrence of the cascade is determined.

Abstract: An anti-lock brake control system capable of performing optimal control of braking hydraulic pressure in a motor vehicle having four wheels while preventing brake application from being released by setting an optimal pseudo vehicle speed by effectively making use of the wheel speeds of four wheels in arithmetic determination of a pseudo vehicle speed on a wheel basis. The anti-lock brake control system includes wheel speed detector (101a to 101d) for detecting rotation speeds of four wheels, respectively, reference wheel speed arithmetic calculators (102a to 102d) for setting limits on the wheel speed of the wheels in consideration of positional relations of the wheels relative to one wheel of concern to thereby determine a reference wheel speed, and pseudo vehicle speed arithmetic calculators (103a to 103d) for arithmetically determining the pseudo vehicle speed on the basis of the reference wheel speed.

Abstract: An anti-lock brake control system for a motor in which influence of vibration of wheel driving shafts occurring upon braking in the state where the wheels (1a, 1b) are operatively connected to a prime mover such as an internal combustion engine is suppressed to thereby enhance the braking performance of the system. Rotation speed (Vw) of each of the driving wheels (1a to 1d) of the motor vehicle is detected for determining wheel acceleration (Gw). A torsion torque (Tt) applied to a wheel drive shaft is detected. The wheel acceleration (Gw) is corrected with the torsion torque (Tt) for determining a corrected acceleration (Gc). The brake application pressure is controlled in dependence on combinations of two variables, i.e., the corrected acceleration (Gc) and the wheel acceleration (Gw).

Abstract: An anti-lock brake control system for motor vehicle which can determine vibrations of wheel speed brought about by rough-road condition and judder phenomenon by detecting a torque applied to a driving shaft of the motor vehicle in association with driving wheels without need for estimating a coefficient of friction of a road surface, to thereby improve and enhance the performance of the anti-lock brake control for the motor vehicle. Whether vibration of the driving wheel is brought about by a judder phenomenon or by a rough-road condition is decided on the basis of predetermined relations between the vibration state of the driving wheel and that of the torsion torque applied to the driving shaft.

Abstract: An apparatus for preventing a brake force from increasing in excess upon starting of an anti-lock brake control for enhancing initial brake performance of an anti-lock brake control system. Rotation speed of each of wheels is detected, and wheel acceleration is determined. Further, a corrected acceleration is determined by correcting the wheel acceleration with a torsion torque detected from a driving shaft. In dependence on the statuses of the wheel acceleration and the corrected acceleration, a rate at which the brake force is increased is modified. Enhanced brake performance in the initial control phase can be ensured when the motor vehicle is running on a road exhibiting high friction coefficient while stability of the motor vehicle running on a road of low friction can be realized. Besides, even when difference frictions act on left and right wheels, the motor vehicle is protected against yawing moment.

Abstract: A low-cost torque detection apparatus is obtained using wheel revolution sensors which are generally provided in a conventional ABS and an engine revolution sensor which is generally provided in a conventional engine fuel jet controller. The apparatus can be used, for example, in a vehicle having a drive source, such as an engine or a motor, for driving wheels which is coupled to the right and left wheels by respective shafts having torsional stiffness for transmitting a drive torque through a differential gear. The apparatus includes a drive source revolution angle detection device for the drive source and wheel revolution angle detection means for the right and left wheels, and calculates torques of shafts such as drive shafts for coupling the differential gear to the wheels using a torque calculator.

Abstract: A anti-skid control system detects a torsion torque applied to each of the wheels of a vehicle, and controls a braking force on the basis of a corrected acceleration as a wheel acceleration is corrected by the detected torsion torque. The corrected acceleration Gc can approximately be expressed by Gc=(Kr/Iw)(.mu..multidot.W.multidot.r-Tb), where Iw, inertia moment of the wheel .omega., angular velocity of the wheel (the turning direction of the wheel when it advances is positive); Tt, torsion torque; .mu., friction coefficient of the road surface; W, load on the wheel; r, radius of the wheel; Tb, brake torque; Kr, constant.