Toyota Jidosha Kabushiki Kaisha

Aisin Seiki Kabushiki Kaisha

Advics Co., Ltd.

Shinichi Tagawa

Shuuichi Buma

Kunihito Sato

Toshio Aburaya

Takashi Yonekawa

Masaki Kawanishi

Toshiaki Hamada

Kouichi Kokubo

Kaoru Ohashi

Hiroyuki Ikemoto

Masaki Banno

Hiroshi Matsuoka

Toshio Onuma

Shoji Inagaki

Nobuyasu Suzumura

Hiroshi Nakashima

Hideo Inoue

Yasuo Uehara

Toshio Oonuma

Kazuki Sugimori

Takeru Tsuji

An inverter apparatus includes: an inverter including three high-voltage side switching elements and three low-voltage side switching elements respectively provided in three phases one by one, and driving a three-phase brushless motor; an opening and closing control unit performing controlling so as to cause an electrical angle of the motor to pass through an angle corresponding to a first combination, to rotate twice by 120&#xb0; each time to one side in a rotary direction, and to rotate once by 120&#xb0; to the other side in the rotary direction thereafter, by sequentially closing four combinations each of which is formed with one among the high-voltage side switching elements and one among the low-voltage side switching elements; and a detection unit detecting a conduction state of a circuit including the closed high-voltage side and low-voltage side switching elements, wherein all the high-voltage side and low-voltage side switching elements are closed at least once in the four combinations.

Inverter apparatus

A road surface friction coefficient &#x3bc; is calculated based on a detected lateral acceleration and a front-rear acceleration, and a roll angle is calculated using a roll rate. Further, a maximum engine torque value that can be applied to a drive wheel without causing slipping thereof is calculated based on the road surface friction coefficient &#x3bc; and a gear ratio. A torque transmission rate that indicates a reduction rate for engine output is set so as to reduce in accordance with a roll angle, and a target engine torque value is calculated by correcting the maximum engine torque value using the torque transmission rate. Accordingly, adjustment is executed such that the engine output is made smaller as the roll angle increases. Thus, abrupt changes in vehicle behavior are not caused by sudden starting of control, and it is possible to inhibit drive feeling from deteriorating.

Anti-rollover device for vehicle

In a case where one of a left and right pair of drive wheels is a non-controlled wheel to which braking force of a vehicle behavior control is not applied, and the other of the drive wheels is a controlled wheel to which braking force is applied, a detected vehicle wheel speed for the non-controlled wheel is corrected to a smaller value in accordance with increase in the roll angle, and increase in the braking force of the controlled wheel when a roll angle of a vehicle body is larger than a threshold value. In a vehicle behavior control, when lateral G acts upon the vehicle during turning, braking force is applied to the controlled wheel that is at the outside of the turn. This braking force application causes driving force of the controlled wheel to be partially transferred to the non-corrected wheel that is at the inside of the turn, whereby the vehicle wheel speed of the non-corrected wheel is increased. Accordingly, in the present invention, correction calculation is performed.

Vehicle wheel speed estimation device, vehicle body speed estimation device and vehicle behavior control apparatus

A system for controlling a steering angle of a vehicle, such as a steering angle of a rear steering wheel, the system having a yaw rate sensor for detecting a yaw rate of the vehicle, an actuator electrically controlled to change the steering angle of the vehicle, and a controller for controlling the actuator to control the steering angle on the basis of an input which includes at least a component derived from the detected yaw rate. The controller includes a detector for detecting an abnormality of a value of the yaw rate detected by the yaw rate sensor, and a limiter for limiting an amount of change in the steering angle to within a predetermined tolerable range when the abnormality is detected.

Vehicle steering control system wherein steering angle change is limited

In order to prevent an inverse rolling or an unnatural rolling of a vehicle body during a turning of the vehicle on a low friction road, in an active suspension having an actuator adapted to increase or decrease vehicle height at the corresponding portion so that the rolling of the vehicle body is suppressed by a control of the actuator carried out in response to a control amount based upon an actual transverse acceleration of the vehicle body and a control amount based upon an estimated transverse acceleration deduced from a steering angle and vehicle speed, the control amount based upon the estimated transverse acceleration is reduced relative to the control amount based upon the actual transverse acceleration when a discrepancy between the estimated transverse acceleration and the actual transverse acceleration increases beyond a predetermined limit of relationship.

Active suspension with roll control by reducibly modified estimated

A fluid pressure type active suspension in a vehicle such as an automobile having a four wheel steering means, including a fluid pressure type actuator provided between the vehicle body and each wheel, working fluid supply and exhaust means for supplying and exhausting a working fluid to and from each actuator, vehicle height detection means for detecting vehicle height of a portion of the vehicle body corresponding to each wheel relative to the wheel, and a control means for controlling the working fluid supply and exhaust means according to control parameters including a vehicle height detected by the vehicle height detection means, wherein the control means is adapted to modify the control of the working fluid supply and exhaust means in accordance with whether a front to rear wheel steering angle ratio of the four wheel steering means is in a same phase region or an opposite phase region so that the vehicle height is controlled to be higher or lower or the rolling control is suppressed less or more according to whether the front to rear wheel steering angle ratio is in the opposite phase region or in the same phase region, respectively.

Fluid pressure type active suspension having variable performance

A suspension pressure control system applies a pressure which is proportional to a current level supplied to a solenoid of a pressure control valve to a shock absorber associated with a suspension from the valve through a cut valve, which cuts off a fluid path from the pressure control valve to the shock absorber when a line pressure is below a predetermined value and communicates the fluid path when the line pressure exceeds the predetermined value. An electronic controller controls the current level to maintain an attitude of a vehicle substantially constant in spite of any change of longitudinal and lateral acceleration, which are detected by acceleration sensors. In order to prevent an abrupt or abnormal change of the pressure of the shock absorber at an initiation of the pressure control of the controller when the vehicle is parking on a slope, the controller initiates the pressure control before the cut valve communicates the fluid path.

Pressure control system for suspension

A suspension pressure control system applies a pressure which is proportional to a current level supplied to a solenoid of a pressure control valve to a shock absorber associated with a suspension from the valve. When a pressure in a high pressure line which feeds a high pressure to the pressure control valve falls (rises), the pressure applied to the suspension is decreased (increased). Accordingly, the pressure in the high pressure line is detected by a sensor, and if it is low (high), the current level of the pressure control valve is corrected to a high value (low value). In order to prevent an abnormal pressure rise in the suspension which may be caused by an excessive pressure rise in the high pressure line during an idling operation of an engine, a correction which responds to the pressure of the high pressure line is chosen large when a vehicle speed is equal to zero or very low. In order to prevent an abnormality from occurring in the correction of the pressure which is attributable to an errorneous detected value during a failure of operation of sensor, such detected value is determined to be faulty, and in the event a fault occurred, the correction is modified to a given volume (0) which is allocated to a standard pressure in the high pressure line.

In a hydraulic suspension system, a plurality of actuators having working fluid chambers are provided. Each actuator is adapted to increase and decrease vehicle height as the results of the supply and the discharge of working fluid to and from its working fluid chamber, respectively. Working fluid supply passages supply working fluid at supply pressure to the working fluid chambers and working fluid discharge passages discharge working fluid from the working fluid chambers. Cut-off valves and pressure control devices are provided in the supply passages and the discharge passages. Each cut-off valve is adapted to remain in its closed position whenever the supply pressure is not more than a predetermined value. Each pressure control device is adapted to control the supply of the working fluid to and the discharge from the associated working fluid chamber to adjust the pressure within the chamber. The system further comprises devices for detecting the pressures within the working fluid chambers and a device for determining the supply pressure. The pressure control devices are controlled so that their controlling pressures may substantially be equal to the pressures within the associated working fluid chambers determined by the pressure determining devices at least until the cut-off valves are opened.

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Toyota, Japan

Shinichi Tagawa