Jtekt Corporation

Mazda Motor Corporation

Toyoda Koki Kabushiki Kaisha

Akira Kodama

Tomohiro Nozu

Masaki Mita

Ryohei Shigeta

Go Nagayama

Yasushi Yagi

Shotaro Niimi

Kenta Taniguchi

Akihiro Tatara

Daisuke Kofu

Hiroaki Kato

Minekazu Momiyama

Akihiro Ohno

Tsuyoshi Murakami

Tomoaki Kato

Takayuki Ohta

Akiyoshi Kakita

Yagi Yasushi

A drive force control device, which controls a drive force distribution device that distributes a drive force to right and left rear wheels at variable distribution ratios, computes a steering angle-based turning radius determined in accordance with a steering angle, computes a limit turning radius, which is a minimum value of the turning radius with which the vehicle is turnable while keeping a stable travel state, in accordance with a vehicle speed, sets the larger one of the steering angle-based turning radius and the limit turning radius as a target turning radius, computes target rotational speeds for the right and left rear wheels on the basis of the target turning radius and the vehicle speed, and adjusts the ratios of distribution of the drive force to the right and left rear wheels such that actual rotational speeds of the right and left rear wheels approximate the target rotational speeds.

Drive force control device and method of controlling vehicle

A driving-force transmitting apparatus includes first and second friction clutches, a piston that presses the first and second friction clutches, a hydraulic pump that feeds hydraulic oil to a cylinder chamber in the piston, an electric motor that drives the hydraulic pump, and a control apparatus that controls the electric motor to adjust the discharge pressure of the hydraulic pump. The control apparatus has a feedback control apparatus that controls the electric motor using a correction value based on a deviation between a target value and an actual value of the discharge pressure of the hydraulic pump, a hydraulic-oil temperature estimating apparatus that estimates a temperature of hydraulic oil, and a gain adjusting apparatus that changes a correction amount for feedback control in accordance with the estimated temperature of the hydraulic oil.

Clutch apparatus and control method for clutch apparatus

A control apparatus controls a driving force transmission device including: an electric motor; a pressing mechanism to convert the rotational force of the motor into an axial pressing force; friction clutches including friction members configured to come into frictional engagement with each other by the pressing force provided by the pressing mechanism. The driving force transmission device is configured to transmit a driving force between a pair of rotary members by the friction clutches. The apparatus includes: a target current calculating circuit to calculate a target current to be supplied to the motor; and a correction circuit to correct a voltage to be applied to the motor so as to reduce a difference between the target current and an actual current supplied to the motor. The correction circuit increases or reduces, in accordance with the actual current, the amount of correction of the voltage to be applied to the motor.

Driving force transmission device control apparatus and control method

Provided is a control device for a four-wheel drive which can maintain driving stability while restraining noise and vibration. A control device includes: a second control device that, when at least one of front wheel has slipped, engages a dog clutch after rotating a propeller shaft by a rotational force transmitted via first and second friction clutches; and a third control device that, if a predetermined condition is satisfied when the front wheels are not slipping, engages the dog clutch after rotating the propeller shaft by the rotational force transmitted via the first and second friction clutches. The time required to synchronize the dog clutch by the third control device is longer than that required to synchronize the dog clutch by the second control device.

Four-wheel drive vehicle and control device for four-wheel drive vehicle

A driving force transmission controller includes: a normal turning control unit that computes command values such that driving force transmitted to an outer wheel in a turning direction is larger than that transmitted to an inner wheel during normal turning; a counter-steering control unit that computes the command values such that the driving force transmitted to the outer wheel is larger than that transmitted to the inner wheel during counter-steering; a counter-steering return control unit that corrects the command values such that a rate of change in each of the driving forces transmitted to the right and left rear wheels is lower than a rate of change in a steered angle of front wheels when a steering velocity is equal to or higher than a prescribed value during the counter-steering; and a driving force transmission control unit that controls a driving force transmission device based on the command values.

Driving force transmission controller and vehicle control method

A driving force transmission control apparatus includes a multiple disc clutch including a plurality of outer clutch plates, and a plurality of inner clutch plates; a pressing mechanism that presses the multiple disc clutch; and a control portion that controls the pressing mechanism. The outer clutch plates and inner clutch plates are engaged with an intermediate shaft and an inner shaft respectively. The control portion makes a determination as to whether the multiple disc clutch is in a first operating condition in which the multiple disc clutch is pressed with a relative rotation speed between the intermediate and the inner shafts being equal to or higher than a predetermined value, or in a second operating condition in which the multiple disc clutch is pressed with the relative rotation speed being lower than the predetermined value, and the control portion controls the pressing mechanism based on a result of the determination.

Driving force transmission control apparatus

A driving force distribution controller comprises: a control device determining the value of torque which must be transmitted to a rear wheel; and a driving force transmission device transmitting torque corresponding to the torque value determined by the control device to the rear wheel. The control device reduces a torque value calculated based on an opening degree of an accelerator and a rotational speed difference when the rotational speed of an engine is lower than a first threshold value but higher than a second threshold value.

Driving force distribution controller and four-wheel drive vehicle

A four-wheel-drive vehicle includes a clutch that is able to allow and interrupt transmission of driving force to a propeller shaft, and a traction control unit that controls at least one of the driving force generated by an engine and braking force applied to right and left front wheels to suppress a slip of the right and left front wheels. When the drive mode is switched from a two-wheel-drive mode to a four-wheel-drive mode, if the relative rotational speed between a first rotary member and a second rotary member constituting a clutch is equal to or higher than a predetermined value, an ECU outputs a control command signal for suppressing the slip of the right and left front wheels to the traction control unit.

Control unit for four-wheel-drive vehicle

A driving force control apparatus includes: a turning radius estimating unit that estimates a turning radius of a four-wheel-drive vehicle; a target slip angle computing unit that computes a target slip angle at the time of turning of the four-wheel-drive vehicle, on the basis of the estimated turning radius; a target rotational speed computing unit that computes target rotational speeds of right and left rear wheels of the four-wheel-drive vehicle, on the basis of the estimated turning radius, the computed target slip angle, and a vehicle speed; and a driving force control unit that controls driving forces that are transmitted to the right and left rear wheels such that actual rotational speeds of the right and left rear wheels approach the computed target rotational speeds.

Driving force control apparatus and vehicle control method

A road surface frictional coefficient estimation device includes: a first straight travel determination unit configured to determine whether or not a vehicle travels straight based on a rotational speed difference between a plurality of wheels of the vehicle; a second straight travel determination unit configured to determine whether or not the vehicle travels straight based on a steering angle of the vehicle; a selection unit configured to select one of determination results of the first straight travel determination unit and the second straight travel determination unit; and a frictional coefficient estimation unit configured to estimate a frictional coefficient of a road surface on which the vehicle travels when the one of the determination results selected by the selection unit indicates that the vehicle travels straight.

Road surface frictional coefficient estimation device, driving force distribution control device and four-wheel-drive vehicle

A driving force distribution control device mounted on a vehicle including an engine, a transmission device, a clutch engaging an output shaft of the engine with an input shaft of the transmission device, and a driving force transmission system capable of transmitting output of the transmission device to main and auxiliary drive wheels, includes: a control device obtaining a torque value to be transmitted to the auxiliary drive wheels, the control device reducing the torque value for a predetermined time when the vehicle is in a stopped state or in a state where a vehicle speed of the vehicle is lower than a predetermined value, and an increasing speed of engaging force of the clutch is equal to or greater than a predetermined value; and a driving force transmitting device transmitting torque depending on the obtained torque value to the auxiliary drive wheels.

Driving force distribution control device and four-wheel-drive vehicle

Front and rear wheels Tf, Tr of a motor vehicle driven by an engineare connected through a differential control devicewhich is capable of varying the torque to transmit. When the turning radius of a predetermined one wheel or the motor vehicle is equal to or smaller than a predetermined turning radius, the transmission torque of the differential control device is decreased by a control device to prevent the tight-corner braking phenomenon from occurring. When the motor vehicle is stopped momentarily with the transmission torque being lowered, the control device maintains the transmission torque as it is, and the vehicle is then restarted with the transmission torque being lowered. Thus, when the motor vehicle which was stopped momentarily with a large steering angle is then restarted, the tight-corner braking phenomenon can be prevented from occurring from the beginning of the restarting.

Drive power transmission equipment

An electronic control unit calculates a target yaw rate in accordance with a vehicle speed and a steering angle and calculates the yaw rate difference on the basis of the target yaw rate and an actual yaw rate. The electronic control unit estimates the grip factor of a front wheel to road surface and sets a distribution ratio for distribution of a vehicle-control target value among actuators of a steering system, a brake system, and a drive system in accordance with the estimated grip factor. The electronic control unit controls the actuators of the three systems in accordance with control instruction values distributed on the basis of the vehicle-control target value and the distribution ratio.

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Chiryu, Japan

Akira Kodama