Jtekt Corporation

Mitsubishi Jidosha Kogyo Kabushiki Kaisha

Aisin Ai Co., Ltd.

Mazda Motor Corporation

Tomoaki Kato

Go Nagayama

Kotaro Sarai

Akihiro Ohno

Akiyoshi Kakita

Ryohei Shigeta

Tetsuya Yamazaki

Hirokazu Kondo

Takeshige Miyazaki

Tsuyoshi Murakami

Tomohiro Nozu

Yoshiyuki Aoyama

Tsutomu Matsumoto

Naoki Sawada

Masaki Mita

Kazutaka Kobayashi

Ryouhei Shigeta

Toshimi Hara

Tadashi Yoshioka

Wataru Hirata

Kenta Taniguchi

Shunzo Tanaka

Masahito Uesaka

Toshihiko Yamamoto

Akira Kodama

Yasushi Yagi

Yasushi Yamada

Shotaro Niimi

Daisuke Kofu

Hiroto Kawano

Yasunari Saito

A vehicle drive device includes a control device, and the control device controls an electric motor, a first pressing mechanism and a second pressing mechanism such that a relational expression of T&#x3c;T+Tis satisfied, where T represents a torque that is input to an input rotation member, Trepresents a maximum of a torque that is able to be transmitted by a first multi-disc clutch and Trepresents a maximum of a torque that is able to be transmitted by a second multi-disc clutch.

Vehicle drive device

A driving force control apparatus for controlling a driving force to be transmitted to a wheel includes a processor. The processor is configured to set, when the wheel is idled, a control amount of the driving force to be transmitted to the wheel based on a vehicle acceleration.

Driving force control apparatus, driving apparatus, and driving force transmission apparatus

A drive force transmission apparatus is mountable on a four-wheel drive vehicle switchable between a four-wheel drive mode that transmits a drive force of an engine to front wheels and rear wheels, and a two-wheel drive mode that transmits the drive force to only the front wheels. The drive force transmission apparatus allows adjustment of the drive force to the rear wheels, and includes a multi-plate clutch, a piston for axially pressing the multi-plate clutch, an actuator for axially moving the piston, and a control unit for controlling the actuator. Upon satisfaction of a predetermined condition that indicates a high probability of the vehicle needing to be switched from the two-wheel drive mode to the four-wheel drive mode, the control unit causes the actuator to displace the piston by a predetermined amount with respect to an initial position of the piston toward the multi-plate clutch.

Drive force transmission apparatus

A control device is mounted on a four-wheel-drive vehicle, and includes a detector and a vibration suppression controller. The detector detects the occurrence of a vibrating state, in which drive wheels and auxiliary drive wheels slip alternately in a four-wheel-drive state in which a drive force is transferred to the auxiliary drive wheels, or the occurrence of a preliminary state for the vibrating state. The vibration suppression controller reduces the drive force which is transferred to the auxiliary drive wheels via a drive force transfer device when the vibrating state or the preliminary state is detected by the detector. The vibration suppression controller reduces the drive force which is transferred to the auxiliary drive wheels on condition that a thermal load of the drive force transfer device is less than a predetermined threshold.

Four-wheel-drive vehicle control device

A driving force transmission control apparatus includes: a driving force transmission device that includes an electromagnetic clutch mechanism configured to generate a frictional force between clutch plates by energization of an electromagnetic coil and transmits a driving force by actuating the electromagnetic clutch mechanism; and a control device that controls the driving force transmission device. The control device includes a storage unit storing a hysteresis value representing the difference between a current value required to transmit a predetermined torque when an energization current to the electromagnetic coil is gradually increased and a current value required to transmit the predetermined torque when the energization current is gradually reduced, a torque command value calculator that calculates a torque command value, and a current command value calculator that calculates a current command value representing a target value of a current to be supplied to the electromagnetic coil based on the torque command value and the hysteresis value.

Driving force transmission control apparatus

A control device controls a driving force transmission device that presses a main clutch using an actuator that generates a pressing force according to a supply current. The control device includes a current command value setting unit that sets a current command value based on I-T characteristic information indicating the relationship between a current supplied to the actuator and a driving force transmitted, a correction duration setting unit that sets a correction duration based on a responsiveness related value related to the responsiveness of the main clutch when an increase in the driving force to be transmitted by the main clutch becomes greater than or equal to a threshold, a correction unit that increases and corrects the current command value for the set correction duration, and the current control unit that performs current feedback control such that a current corresponding to the current command value is supplied to the actuator.

In a four-wheel-drive vehicle, a hydraulic unit has an electric motor, to which a motor current is supplied from a control device, and a pump that is actuated by rotation of a motor shaft, and a drive force transfer device has a piston that is moved by the pressure of working oil discharged from the pump, and a friction clutch that is switchable between a transfer state and a blocked state, in which transfer of a drive force to rear wheels is allowed and blocked, respectively, in accordance with movement of the piston. The control device detects the presence or absence of an abnormality of a flow passage forming member, which forms a flow passage for working oil, in accordance with at least any of a motor current and the number of revolutions of a motor shaft at the time when the motor shaft is rotated by applying a voltage to the electric motor.

Four-wheel-drive vehicle

A controller for a driving force transmitting apparatus mounted in a four-wheel-drive vehicle, includes: a driving force controller configured to calculate a command torque indicating a driving force to be transmitted to the sub-drive wheels via the driving force transmitting apparatus based on a traveling state of the four-wheel-drive vehicle and a road surface condition, and to control the driving force transmitting apparatus based on the command torque; and a road surface condition determiner configured to determine that the road surface condition is a high-&#x3bc; condition when a duration of a non-slipping state where a vehicle speed is equal to or higher than a prescribed value and a slip ratio of each of both the main drive wheels is lower than a prescribed value has become equal to or longer than a prescribed time.

Controller for driving force transmitting apparatus

A control device mounted on a four-wheel drive vehicle includes: a slip ratio calculating unit that obtains a slip ratio of main driving wheels based at least on wheel speeds; a smoothing unit that smooths the slip ratio by filtering; and a driving force control unit that controls a driving force transmission device so that a driving force that is transmitted to auxiliary driving wheels increases as the slip ratio smoothed by the smoothing unit increases. The smoothing unit uses a larger time constant for the filtering when a vehicle speed is less than a predetermined value than when the vehicle speed is equal to or higher than the predetermined value

Control device for driving force transmission device

In a control device for a limited slip differential that limits a differential operation of front and rear wheels of a four-wheel-drive vehicle having mounted thereon a vehicle behavior control device that controls a braking force, an ECU that controls a torque coupling as the limited slip differential includes: a differential limiting force calculating device that calculates target torque of the torque coupling based on a vehicle traveling state; a differential limiting force correcting device that makes a correction to reduce the target torque based on a command from the vehicle behavior control device; and a thermal load calculating device that calculates a thermal load of the torque coupling. The differential limiting force correcting device limits the correction of the target torque based on the command from the vehicle behavior control device, when the thermal load of the torque coupling is equal to or larger than a predetermined value.

Device and method for controlling limited slip differential

A driving force distribution control apparatus includes: a driving force transmission device including a clutch which can change distribution of a driving force to front wheels and rear wheels of a four-wheel drive vehicle; and a controller which controls an engagement force of the clutch in accordance with a traveling state. The controller includes a different-diameter tire detector which detects an attachment of a different-diameter tire to one of the front wheels and the rear wheels when a rotation speed ratio between the front wheels and the rear wheels continues to be equal to or larger than a reference rotation speed ratio for a predetermined time. The different-diameter tire detector performs detection of the attachment of the different-diameter tire when it is determined that the wheels are unlikely to slip based on an outside condition.

Driving force distribution control apparatus

A drive state control apparatus is applied to a vehicle which has not only a transfer including a multi-disc clutch mechanism but also a changeover mechanism interposed in an axle and which can be switched between 2WD and 4WD. When a 2WD-to-4WD changeover condition is satisfied, the multi-disc clutch is immediately switched from a 'decoupled state' to a 'coupled state.' Meanwhile, a connecting operation of the changeover mechanism is started upon establishment of a state in which left and right rear wheels have no acceleration slippage, and a state in which rotational speeds of first and second axles on opposite sides of the changeover mechanism are approximately equal to each other. In addition, in the case where the left and right rear wheels have acceleration slippage after the 2WD-to-4WD changeover condition has been satisfied, an E/G output reduction control is executed. Thus, the connecting operation can be performed smoothly.

Drive state control apparatus for 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

An on-demand-type drive state control apparatus for a vehicle is provided. In the case where acceleration slippage occurs at drive wheels (rear wheels) of a vehicle when a drive system is in a two-wheel drive state, the drive system is switched from the two-wheel drive state to a four-wheel drive state. That is, the maximum transmittable torque of a multi-disc clutch mechanism increases from '0' to a predetermined value. In the four-wheel drive state, the maximum transmittable torque decreases stepwise from the present value by a predetermined value every time the vehicle travels over a predetermined distance in a state in which none of the wheels cause acceleration slippages. That is, the clutch drive current supplied to the multi-disc clutch mechanism decreases gradually (stepwise or in a plurality of steps), and the drive torque distributed to the front wheels (rear wheels) decreases (increases) gradually.

A vehiclehas a torque coupling, which is located in a driving power transmission system for transmitting the torque of an engineto front and rear wheels. The torque couplingchanges the torque distribution by adjusting the frictional engaging force of an electromagnetic clutch. The vehiclealso has a 4WD ECU(CPU), which controls the operation of the torque couplingbased on the driving state. The 4WD ECU(CPU) estimates a transfer case oil temperature Tptu. When the transfer case oil temperature Tptu is higher than or equal to a first predetermined transfer case oil temperature KTptu, the 4WD ECUexecutes overheat prevention control. When the deviation &#x394;A between an estimated vehicle acceleration Ae, which is computed based on a predetermined vehicle weight M and a driveline torque &#x3c4;d of the engine, and the actual vehicle acceleration Av is greater than or equal to a first predetermined deviation K&#x394;A, the 4WD ECU(CPU) estimates the transfer case oil temperature Tptu to be higher. This allows the control mode of the torque couplingto be smoothly switched to the overheat prevention control.

Growing community of inventors

Kariya, Japan

Tomoaki Kato