Patent classifications
F16H59/22
Vehicle control device and vehicle control method
The present invention relates to a control device and a control method for a vehicle in which a lockup clutch is disengaged when a rotation speed of an engine falls below a disengagement rotation speed. The device/method changes a speed ratio of a variator on the basis of a shifting map in which a primary pulley rotation speed on a coast line is set higher than a primary pulley rotation speed on a drive line and sets a target input rotation speed of the variator to a predetermined target input rotation speed higher than the primary pulley rotation speed on the drive line when an operation of an accelerator pedal is performed such that an accelerator pedal opening falls to a first predetermined opening or less. As a result, the present invention can suppress drop of fuel efficiency of the engine caused by disengagement of the lockup clutch which is a friction engagement element.
CONTROL DEVICE FOR AUTOMATIC TRANSMISSION AND CONTROL METHOD FOR AUTOMATIC TRANSMISSION
A control device that controls an automatic transmission is provided, in which device the automatic transmission includes a variator disposed in a power transmission path between a driving source and a driving wheel of a vehicle, and a friction engaging element disposed between the variator and the driving wheel, in a manner capable of transmitting a power disconnectably via the power transmission path. The control device increases a speed ratio of the variator toward a predetermined target speed ratio with disengaging the friction engaging element during a vehicle stop of the vehicle, and executes a learning regarding a hydraulic control of the friction engaging element when the friction engaging element is disengaged during the vehicle stop. The control device decreases the target speed ratio at a time of learning when the learning is executed during the vehicle stop, compared to a time of vehicle stop other than the time of learning.
METHOD FOR CONTROLLING AN AUTOMATIC GEARBOX FOR A MOTOR VEHICLE
A method for controlling an automatic gearbox for a motor vehicle having at least two different drive train states. The method includes: determining minimum deceleration force requirement that needs to be achieved by the drive train state depending on speed of the vehicle, longitudinal acceleration, and resistive forces experienced by the vehicle, then taking a decision to authorize or prohibit the drive train state for which the minimum deceleration force requirement has been calculated depending on the deceleration force setpoint, the current drive chain state, and the minimum force achievable by the drive train state in question.
ELECTRIC-VEHICLE CONTROL DEVICE AND CONTROL METHOD
In a specific state where an electric vehicle is in a stop state and a creep torque is generate in an electric motor (2), when a shift range is switched from a traveling range to a non-traveling range, a motor control section (10B) performs a torque decrease control to stepwisely decrease the creep torque of the electric motor (2), and an automatic transmission control device (30) performs a disengagement control to gradually disengage the frictional engagement element of the automatic transmission (3).
CONTROL DEVICE AND CONTROL METHOD FOR CONTINUOUSLY VARIABLE TRANSMISSION MECHANISM FOR VEHICLE
A control device for a continuously variable transmission mechanism of a vehicle includes: a stepwise variable transmission mechanism which is disposed in series with the continuously variable transmission mechanism, and which has at least two or more forward gear stages; and a controller configured to increase the belt capacities to be greater than the belt capacity set when an accelerator opening degree is zero, at least in a time period from a timing when the accelerator opening degree becomes zero, to a timing when a braking force is generated by a depression of a brake pedal, the controller being configured to set an increase amount with respect to the belt capacity set when the accelerator opening degree is zero, to a smaller value as a transmission gear ratio of the stepwise variable transmission mechanism is higher.
Continuously variable transmission (CVT) ratio control
A vehicle includes an engine with an associated engine-speed sensor, and wheels each having a respective wheel-speed sensor. The vehicle also includes a continuously variable transmission (CVT) coupled to the engine and configured to operate at variable input-to-output ratios. At least one controller is programmed to reduce the operating ratio of the CVT in response to the engine-speed sensor indicating the engine is operating at idle speed and the wheel-speed sensor indicating the velocity is approximately zero. This provides less noise, vibration and harshness in the vehicle due to the reduced ratio that is possible during conditions in which a vehicle launch in that reduced ratio may not be acceptable.
VEHICLE CONTROL DEVICE AND VEHICLE CONTROL METHOD
The present invention relates to a control device and a control method for a vehicle in which a lockup clutch is disengaged when a rotation speed of an engine falls below a disengagement rotation speed. The device/method changes a speed ratio of a variator on the basis of a shifting map in which a primary pulley rotation speed on a coast line is set higher than a primary pulley rotation speed on a drive line and sets a target input rotation speed of the variator to a predetermined target input rotation speed higher than the primary pulley rotation speed on the drive line when an operation of an accelerator pedal is performed such that an accelerator pedal opening falls to a first predetermined opening or less. As a result, the present invention can suppress drop of fuel efficiency of the engine caused by disengagement of the lockup clutch which is a friction engagement element.
Transmission control device for automatic transmission
A transmission controller includes: a corner detector that detects a corner; a predictor to predict a rolling amount based upon road data when the corner is detected and an accelerator opening degree is fully closed; a device to determine a first necessary engine braking amount in accordance with the rolling amount; a device to determine a first required speed change stage corresponding to the first necessary engine braking amount; a calculator to calculate a second necessary engine braking amount when the corner is detected and the accelerator opening degree is fully closed based upon a minimum required inter-vehicle distance with the vehicle ahead; a device to determine a second required speed change stage corresponding to the second engine braking amount; and a transmission controller to select, as a target speed change stage, either smaller one of the first or second required speed change stage, and then perform downshift control.
Transmission control device for automatic transmission
A transmission controller includes: a corner detector that detects a corner; a predictor to predict a rolling amount based upon road data when the corner is detected and an accelerator opening degree is fully closed; a device to determine a first necessary engine braking amount in accordance with the rolling amount; a device to determine a first required speed change stage corresponding to the first necessary engine braking amount; a calculator to calculate a second necessary engine braking amount when the corner is detected and the accelerator opening degree is fully closed based upon a minimum required inter-vehicle distance with the vehicle ahead; a device to determine a second required speed change stage corresponding to the second engine braking amount; and a transmission controller to select, as a target speed change stage, either smaller one of the first or second required speed change stage, and then perform downshift control.
VEHICLE CONTROL DEVICE AND METHOD FOR CONTROLLING THE SAME
A vehicle control device for controlling a vehicle including an oil pump driven by a transmission of a rotation of the motor-generator; and a hydraulic pressure supply unit for supplying a hydraulic pressure to the continuously variable transmission. The hydraulic pressure is generated by regulating a pressure of an oil discharged from the oil pump. When a regenerative braking is performed by the motor-generator based on a deceleration request from a driver, the hydraulic pressure supply unit supplies a hydraulic pressure based on a first hydraulic pressure and a second hydraulic pressure to the continuously variable transmission. The first hydraulic pressure is a hydraulic pressure to transmit an input torque input to the continuously variable transmission during the regenerative braking. The second hydraulic pressure is a hydraulic pressure to shift the continuously variable transmission during the regenerative braking. During the regenerative braking, the first hydraulic pressure is set to equal to or less than a hydraulic pressure found by subtracting the second hydraulic pressure from a hydraulic pressure suppliable to the continuously variable transmission.