Abstract: A variable transmission ratio steering apparatus for a vehicle is configured with an input shaft coupled to a steering wheel of the vehicle, a sensor for sensing a rotation angle of the input shaft, an output shaft operatively linked to steerable road wheels of the vehicle, an actuator having an electric motor which is configured to vary a transmission ratio between a rotation angle of the output shaft and the rotation angle of the input shaft, and a controller. More specifically, the controller includes a desired rotation angle calculation unit, a difference calculation unit, and a difference limitation unit, whereby a rotation angle of a rotor of the electric motor is limited. With such a configuration, a rotation speed of the rotor of the electric motor can be limited by limiting the rotation angle of the rotor, and consequently, audible operation noises arising from the electric motor can be minimized.

Abstract: An inverter circuit includes a bridge circuit constituted of a plurality of pairs of a high-side switching element and a low-side switching element, a command signal processing section, a pulse generating section for generating pulse signals to control the inverter bridge circuit according to the command signal to have a dead time to prevent short circuiting of the dc power source and a command signal compensation section. The compensation section modifies the command signal according to a current voltage level of the dc power source to control the dead zone, thereby preventing deformation of ac output power of the bridge circuit.

Abstract: A motor controller including an inverter including plural switching elements that are subjected to PWM control to generate sine waves of plural phases, a motor including a stator coil supplied with the sine waves thus generated so that rotational magnetic field is generated in the stator coil, and a rotor that is rotationally driven by the action of the rotational magnetic field generated by the stator coil, a storage unit for detecting the sine waves of the respective phases generated in the inverter and storing a correction amount for each phase that is calculated on the basis of the detection result so that the sine waves of the respective phases are coincident with one another and a correcting unit for correcting a PWM signal for carrying out the PWM control on the switching elements on the basis of the correction amount thus calculated.

Abstract: An electric steering control device is provided which is capable of enabling the driver to perform steering manipulation stably without being substantially affected by the ambient temperature and the heat generation of the control device. The control device comprises a temperature sensor for detecting the temperature of a circuit board mounting a motor drive circuit thereon and a compensation section for compensating an electric current command value based on the board temperature detected by the temperature sensor, so that en electric motor for exerting an assist force on a vehicle steering mechanism is driven by the compensated electric current command value output from a motor drive circuit. Therefore, the steering operation can be done stably without being substantially affected by the ambient temperature and the heat generation of the control device.

Abstract: In a neutral position detection error protecting apparatus, vehicle wheel velocities of right/left driven wheels are detected and a right/left wheel velocity difference is obtained. Then, when a right/left wheel velocity difference is less than a predetermined velocity a steering rotation angle is more than a predetermined value and a vehicle wheel velocity is more than a predetermined velocity in a predetermined period, it is determined that there is an abnormality in the vehicle wheel velocities.

Abstract: A drive controlling unit includes a final angle position memorizing device for memorizing a final angle position at a time of termination of the vehicle driving operation, an input complete data memorizing device capable of switching the memory content between a first memory condition and a second memory condition. The first memory condition indicates completeness of writing of the final angle position in the final angle position memorizing device. The second memory condition indicates failure in writing the final angle position therein. The input complete data memorizing device is capable of maintaining the memory content even when the vehicle is stationary.

Abstract: A target relative rotational angle ??t which is created by a steering gear ratio change unit and which is formed by a lower steering shaft relative to an upper steering shaft is calculated on the basis of a steering angle ?, and a post-correction target relative rotational angle ??ta to be created by the steering gear ratio change unit is calculated on the basis of the target relative rotational angle ??t and a vehicle speed range that has been determined on the basis of a vehicle speed V. Thus, a target relative rotational angle in one lateral direction is so corrected as to be equal to or smaller than a difference between a permissible rotational angle to be defined by a spiral cable in the other lateral direction and a maximum possible rotational angle of the lower steering shaft in the other lateral direction. An electric motor is controlled on the basis of the post-correction target relative rotational angle ??ta.

Abstract: A vehicular steering control apparatus controls the wheel steering amount of wheels based on a steering angle and an assist angle obtained by multiplying a steering speed by a gain. If the amount of power control differs between the left wheel and the right wheel, the value of gain is increased. The amount of power control includes, for example, the amount of braking control and the amount of drive control. If the assist angle is increased by increasing the gain, the magnitude of the wheel steering amount relative to the steering angle increases, so that a driver can correct the orientation of the vehicle body by performing a small amount of steering operation.

Abstract: A drive controlling means includes a final angle position memorizing means for memorizing a final angle position at a time of termination of the vehicle driving operation, an input complete data memorizing means capable of switching the memory content between a first memory condition and a second memory condition. The first memory condition indicates completeness of writing of the final angle position in the final angle position memorizing means. The second memory condition indicates failure in writing the final angle position therein. The input complete data memorizing means is capable of maintaining the memory content even when the vehicle is stationary.

Abstract: A PWM control includes a first PWM control and a second PWM control. In the first PWM control, a first power supply terminal of a first coil is kept non-switched under being connected to a first pole of a direct current power source, and a second power supply terminal of a second coil is capable of being switched under being connected to a second pole of the direct current power source. The second PWM control is performed by switching a first connected condition and a second connected condition by turns. The first connected condition is established with the first power supply terminal connected to the first pole and the second power supply terminal connected to the second pole. The second connected condition is established with the first power supply terminal being connected to the second pole and the second power supply terminal being connected to the first pole.

Abstract: A vehicle steering apparatus is provided with a transmitting ratio variable gear ratio mechanism in a steering force transmitting system, and a lock mechanism which limits relative rotation between an input shaft and an output shaft of the steering force transmitting system. In the lock mechanism is provided a lock holder which rotates together with a rotor of a motor, and in which is formed a plurality of first indented portions in a circumferential direction along the circumference and a second indented portion indented deeper than the first indented portions at one end portion of each of the first indented portions. In the lock mechanism is also provided a lock arm which is provided on a stator side of the motor and which engages with the one of the first indented portions or second indented portions.

Abstract: A vehicle steering apparatus includes a variable gear ratio mechanism which is provided in a steering force transmitting system, and a lock mechanism which restricts relative rotation of an input shaft and an output shaft of the transmitting ratio changing mechanism. The lock mechanism is engaged by inserting a lock arm in a indented portion of a lock holder of the lock mechanism. A play angle when the lock mechanism is engaged by inserting the lock arm in the indented portion is set to be smaller than a rotational angle of a motor which is required for outputting six different signals.

Abstract: A PWM control includes a first PWM control and a second PWM control. In the first PWM control, a first power supply terminal of a first coil is kept non-switched under being connected to a first pole of a direct current power source, and a second power supply terminal of a second coil is capable of being switched under being connected to a second pole of the direct current power source. The second PWM control is performed by switching a first connected condition and a second connected condition by turns. The first connected condition is established with the first power supply terminal connected to the first pole and the second power supply terminal connected to the second pole. The second connected condition is established with the first power supply terminal being connected to the second pole and the second power supply terminal being connected to the first pole.

Abstract: A angle sensor 103 identifies a angle phase of a rotatable member based on a kind of an identified pattern of the angle phase to detect an angular position of a steering shaft driven by a motor 6. A steering controller 100 identifies a rotational direction based on an identified pattern output of the angle and performs a sampling of the pattern output at a predetermined interval, identifies an order of combination order of the identified pattern of an angle phase in a first sampling and a second sampling following to the first sampling, and determines a pattern exchange number with the rotational direction from the order in the first sampling to the order in the second sampling.

Abstract: An electric steering control device is provided which is capable of enabling the driver to perform steering manipulation stably without being substantially affected by the ambient temperature and the heat generation of the control device. The control d vice comprises a temperature sensor for detecting the temperature of a circuit board mounting a motor drive circuit thereon and a compensation section for compensating an electric current command value based on the board temperature detected by the temperature sensor, so that en electric motor for exerting an assist force on a vehicle steering mechanism is driven by the compensated electric current command value output from a motor drive circuit. Therefore, the steering operation can be done stably without being substantially affected by the ambient temperature and the heat generation of the control device.

Abstract: A angle sensor 103 identifies a angle phase of a rotatable member based on a kind of an identified pattern of the angle phase to detect an angular position of a steering shaft driven by a motor 6. A steering controller 100 identifies a rotational direction based on an identified pattern output of the angle and performs a sampling of the pattern output at a predetermined interval, identifies an order of combination order of the identified pattern of an angle phase in a first sampling and a second sampling following to the first sampling, and determines a pattern exchange number with the rotational direction from the order in the first sampling to the order in the second sampling.

Abstract: A vehicle steering apparatus is provided with a transmitting ratio variable gear ratio mechanism in a steering force transmitting system, and a lock mechanism which limits relative rotation between an input shaft and an output shaft of the steering force transmitting system. In the lock mechanism is provided a lock holder which rotates together with a rotor of a motor, and in which is formed a plurality of first indented portions in a circumferential direction along the circumference and a second indented portion indented deeper than the first indented portions at one end portion of each of the first indented portions. In the lock mechanism is also provided a lock arm which is provided on a stator side of the motor and which engages with the one of the first indented portions or second indented portions.

Abstract: In a neutral position detection error protecting apparatus, vehicle wheel velocities SFR, SFL of right/left driven wheels FR, FL are detected by vehicle wheel sensors 27a, 27b and a right/left wheel velocity difference VFD is obtained from vehicle wheel velocities VFR, VFL of the driven wheels FR, FL through vehicle wheel velocity signal abnormality determining processing 30b so as to detect steering angle information &thgr;h from the steering wheel 21.

Abstract: The invention relates to a vehicle steering apparatus including a variable gear ratio mechanism which is provided in a steering force transmitting system, and a lock mechanism which restricts relative rotation of an input shaft and an output shaft of the transmitting ratio changing mechanism. The lock mechanism is engaged by inserting a lock arm in a indented portion of a lock holder of the lock mechanism. A play angle when the lock mechanism is engaged by inserting the lock arm in the indented portion is set to be smaller than a rotational angle of a motor which is required for outputting six different signals.

Abstract: A target relative rotational angle &Dgr;&thgr;t which is created by a steering gear ratio change unit and which is formed by a lower steering shaft relative to an upper steering shaft is calculated on the basis of a steering angle &thgr;, and a post-correction target relative rotational angle &Dgr;&thgr;ta to be created by the steering gear ratio change unit is calculated on the basis of the target relative rotational angle &Dgr;&thgr;t and a vehicle speed range that has been determined on the basis of a vehicle speed V. Thus, a target relative rotational angle in one lateral direction is so corrected as to be equal to or smaller than a difference between a permissible rotational angle to be defined by a spiral cable in the other lateral direction and a maximum possible rotational angle of the lower steering shaft in the other lateral direction. An electric motor is controlled on the basis of the post-correction target relative rotational angle &Dgr;&thgr;ta.