Patent classifications
F16H2061/6615
Shift control device
A shift control device has stepless and stepped shift modes in which a transmission gear ratio of a continuously variable transmission is controlled in stepless and stepwise fashions, respectively, and includes a mode setting unit that switches the shift mode to the stepped shift mode if an engine rotation speed in the stepless shift mode exceeds a switch threshold, a correction-value setting unit that sets a correction value based on the engine rotation speed if the shift mode is to be switched to the stepped shift mode, a shift-threshold setting unit that sets a shift threshold by adding the correction value to the switch threshold if the shift mode is to be switched to the stepped shift mode, and an upshift controller that switches the transmission gear ratio toward a higher side when the engine rotation speed in the stepped shift mode reaches the shift threshold.
Vehicle control device
A vehicle control device is provided which is capable of properly satisfying an acceleration request from a driver even when the driver performs a step-on operation of an accelerator pedal in the implementation of an ACC mode. The vehicle control device is capable of: a front car follow-up travel mode, in which a driving force and a transmission ratio are controlled based on a first accelerator position (AP1) for an inter-vehicle distance to a preceding vehicle to be a target inter-vehicle distance; and an override mode, in which the driving force and the transmission ratio are controlled based on a second accelerator position (AP2) determined by an operation of an accelerator operator performed by a driver. Compared with a second transmission characteristic selected in the override mode, in a first transmission characteristic selected in the front car follow-up travel mode, a threshold of the accelerator position at which at least downshift of a transmission (TM) occurs is set to a higher value or an amount of change of the transmission ratio along with the downshift of the transmission (TM) is set to a lower value.
DEVICE AND METHOD FOR CONTROLLING CONTINUOUSLY VARIABLE TRANSMISSION
A continuously variable transmission (2) has a torque convertor (3) having a lock-up clutch (30) and a continuously variable transmission mechanism (5). A control unit (10) has a shift control unit (10C) configured to be able to perform a pseudo stepwise up-shift control that varies a transmission ratio of the continuously variable transmission mechanism (5) stepwise, a lock-up control unit (10A) configured to control an engagement state of the lock-up clutch (30), and a torque control command unit (10D) configured to perform a torque-down control of a driving source (1). When the engagement control of the lock-up clutch (30) and the pseudo stepwise up-shift control are performed at the same time, the torque control command unit (10D) configured to perform the torque-down control with a greater torque reduction mount.
SIMULATED REV-MATCHING IN A VEHICLE HAVING A TWO MOTOR HYBRID SYSTEM TRANSMISSION
Systems and methods are provided for simulating rev-matching in hybrid electric vehicles (HEVs), e.g., HEVs having a two motor hybrid system transmission. In particular, increased engine response is provided while downshifting during acceleration. The two-motor hybrid system transmission may include an electronic control unit that controls the speed of the engine to simulate gears, and increases the speed of the engine responsive to a driver using the gear selector to shift from one of the simulated gears to a lower one of the simulated gears, thereby providing the desired rev-matching experience.
Shift control device
A shift control device includes: a stepless shift controller executing a stepless shift mode and controlling a transmission gear ratio of a continuously variable transmission in a stepless fashion; a stepped shift controller executing a stepped shift mode and controlling the continuously variable transmission using fixed transmission gear ratios; a mode setting unit switching the shift mode to the stepped shift mode when a vehicle is to be accelerated; and a transmission-gear-ratio setting unit setting an initial transmission gear ratio in the stepped shift mode when the shift mode is to be switched to the stepped shift mode. The transmission-gear-ratio setting unit estimates a variation in an engine rotation speed when the shift mode is to be switched to the stepped shift mode, and sets a fixed transmission gear ratio, at which the variation is greater than or equal to a lower limit value, as the initial transmission gear ratio.
Gear shift control device and gear shift control method for continuously variable transmission
A gear shift control device for a continuously variable transmission of a vehicle is configured to steplessly and continuously change and output a rotation speed of an engine. The gear shift control device includes a gear shift control unit and a torque control command unit. The gear shift control unit is configured to implement a pseudo-stepped upshift control to change a gear shift ratio in steps when upshifting the continuously variable transmission. The torque control command unit is configured to output a torque reduction command so as to reduce an engine torque in conjunction with the pseudo-stepped upshift control so that reduction of the engine torque starts before a point in time when an actual gear shift ratio starts changing in response to an upshift command.
Transmission control device
A transmission control device controls a CVT installed in a vehicle. The device has, as modes for the CVT, a CVT mode M1 for changing a transmission gear ratio steplessly based on the operating state of the vehicle, and a stepped transmission mode M2 for changing the transmission gear ratio stepwise based on the operating state of the vehicle. The device includes a transmission mode switching control unit (controller) 12 for controlling switching between the CVT mode M1 and the stepped transmission mode M2 based on an actual accelerator opening. The transmission mode switching control unit (controller) 12 performs switching from the CVT mode M1 to the stepped transmission mode M2, if the actual accelerator opening reaches or exceeds a first threshold value T1 set in a plurality of stages so as to increase stepwise in accordance with an increase in a vehicle speed.
Control device for continuously variable transmission and control method for continuously variable transmission
A continuously variable transmission is mounted in a vehicle, and includes a primary pulley, a secondary pulley, and a belt, wherein the belt is wound around the primary pulley and the secondary pulley. A control device performs a low speed position return control by a feedback control employing a control input integral component. The low speed position return control is to control a transmission ratio to a final target transmission ratio for lower speed position while the vehicle is decelerating. The control device performs a limiting control in response to a condition that the transmission ratio has reached the final target transmission ratio during the low speed position return control. The limiting control is to limit the control input integral component based on thrust balance between the primary pulley and the secondary pulley so as to maintain the transmission ratio at the final target transmission ratio.
TRANSMISSION CONTROL DEVICE
A transmission control device controls a CVT installed in a vehicle. The device has, as modes for the CVT, a CVT mode M1 for changing a transmission gear ratio steplessly based on the operating state of the vehicle, and a stepped transmission mode M2 for changing the transmission gear ratio stepwise based on the operating state of the vehicle. The device includes a transmission mode switching control unit (controller) 12 for controlling switching between the CVT mode M1 and the stepped transmission mode M2 based on an actual accelerator opening. The transmission mode switching control unit (controller) 12 performs switching from the CVT mode M1 to the stepped transmission mode M2, if the actual accelerator opening reaches or exceeds a first threshold value T1 set in a plurality of stages so as to increase stepwise in accordance with an increase in a vehicle speed.
SHIFT CONTROL DEVICE
A shift control device has stepless and stepped shift modes in which a transmission gear ratio of a continuously variable transmission is controlled in stepless and stepwise fashions, respectively, and includes a shift controller that switches the shift mode to the stepless shift mode by executing shift control of the transmission if an accelerator-pedal operated amount falls below a switch threshold during the stepped shift mode, a minimum value detector that detects an operated-amount minimum value in a shift process of switching the shift mode to the stepless shift mode, and an upper-limit-value setting unit that sets an upper limit value for engine rotational acceleration based on a difference between the operated amount and the minimum value in the shift process. In the shift process, the shift controller limits the rotational acceleration to the upper limit value or lower by limiting a shift rate when the transmission is downshifted.