Honda Giken Kogyo Kabushiki Kaisha

Shinji Okuma

Masakatsu Hori

Akihiro Iwazaki

Tatsuhiro Tomari

Takashi Kuribayashi

Kazuhiro Wada

Hiromi Inagaki

Tomoyuki Shinmura

Kiyoshi Wakamatsu

Ryuji Asada

In a vehicle in which a torque generated in an engine is transmitted to driven wheels through a torque converter and an automatic transmission, when a speed ratio e in the torque converter is equal to or larger than a predetermined value (e.g., 0.85), and the accuracy of estimating a capacity &tgr; of the torque converter is low, an estimated engine torque Ti is multiplied by a torque ratio k of the torque converter to estimate a drive torque Td. When the speed ratio e in the torque converter is smaller than the predetermined value, and a response lag is produced in the transmission of the engine torque, a drive torque Td is estimated from an engine rotational sped Ne and the speed ratio e in the torque converter. During shifting of the automatic transmission, a drive torque Td is estimated from a wheel speed V. Thus, a correct drive torque can be estimated.

Process for estimating drive torque in vehicle

A driving force distribution device which controls the engagement forces of electromagnetic clutches and which govern the torque distribution between the driving wheels of a vehicle by calculating a target magnetic flux density and converting the same into a target excitation current. Since the relationship between the target magnetic flux density and the target excitation current changes according to a decrease in the air gaps accompanying wear of the frictional engagement members of the electromagnetic clutches, a relationship between the magnetic flux density and the excitation current is determined by applying current to the electromagnetic clutches when torque distribution control is not being carried out such as when the system is started, and the target excitation current is calculated from the target magnetic flux density based on the determined relationship. Since there is no need to detect dynamic changes in the magnetic flux density, inexpensive devices can be used as magnetic flux density detecting means so contributing to a reduction in the cost.

Driving force distribution device for vehicle

An electric power steering system for a vehicle that consists of a motor control signal calculation device for calculating a motor control signal for driving a motor to generate a steering assist torque, which is based on at least a steering torque detected by a steering torque sensor, a motor control signal correction calculation device for calculating a corrected motor control signal from an amount of motor control signal correction calculated by an external control device and the motor control signal, a driving device for driving a motor based on the corrected motor control signal calculated by the motor control signal correction calculation device; and a motor control signal correction amount reducing device for reducing the amount of motor control signal correction according to vehicle speed.

Electric power steering system

A co-operative control system for a vehicle including a force distribution device for distributing the driving force or braking force between the right and left wheels or between the front and rear wheels, includes a first control means for controlling the operation of the force distribution device, an electric power steering device, having a motor for applying a steering assist torque to a vehicle steering system, and a second control means for calculating a motor control signal for driving the motor. The motor control signal is based on at least the steering torque detected by a steering torque detecting means. The first control means calculates a correction signal for correcting said motor control signal based on the distributed force generated by the force distribution device, the second control means drives the motor based on the corrected motor control signal obtained by correcting the motor control signal with the correction signal and the first control means stops the operation of the force distribution device when the electric power steering device or the second control means malfunctions.

Co-operative control system for a vehicle

A co-operative control system for a vehicle having a force distribution device for distributing at least one of a driving force and a braking force between spaced apart wheels, the co-operative system having: a first control mechanism for controlling the operation of the force distribution device, an electric power steering device having a motor for applying a steering assist torque to a steering system of the vehicle, and a second control mechanism for calculating a motor control signal for driving the motor based on at least a steering torque detected by a steering torque sensor, and for inhibiting drive of the motor based on at least an actual motor detected by a current sensor and the steering torque. The first control mechanism calculates a correction signal for correcting the motor control signal based on the amount of control of the force distribution device and an offset current for correcting the actual motor current signal; and the second control mechanism drives the motor based on a corrected motor control signal obtained by correcting the motor control signal with the correction signal and inhibits the drive of the motor based on a value obtained by correcting the actual motor current signal with the offset current and the steering torque signal, the offset current being set smaller than the correction signal.

Growing community of inventors

Wako, Japan

Shinji Okuma