Abstract:
The vehicle comprises a continuously variable transmission and traction control system (TCS) which controls a driving force. When the TCS is not operating, a controller computes a final target ratio based on a sensor detected vehicle speed. When the TCS is operating, the final target ratio is computed based on an estimated vehicle speed, and the final target ratio is limited by a speed ratio upper limiting value computed based on the sensor detected vehicle speed. The controller controls a speed change actuator so that a real speed ratio approaches the final target ratio.
Abstract:
A control apparatus for a synchromesh type automatic transmission system of a motor vehicle capable of suppressing speed-stage downshift operation which may occur successively upon application of sudden braking as well as occurrence of a gear squeaking phenomenon and shock due to speed change brought about by the downshift operation. The control apparatus includes a shift/select actuator of a multi-stage speed change gear unit (3), a brake switch an accelerator pedal position sensor, an output rotation speed sensor, and a speed stage control means for controlling the shift/select actuator on the basis of detection signals outputted from the sensors. When it is decided that the brake switch is in a closed state and that the deceleration determined arithmetically on the basis of the vehicle speed is not greater than a predetermined value the multi-stage speed change gear unit is shifted to a neutral position and thereafter the decision as to the speed change is suspended.
Abstract:
When a slip control system starts operating, a vehicle speed VSP used for speed change control is simultaneously changed over from a sensor detected vehicle speed VSPSEN to an estimated vehicle speed VSPFL. On the other hand, when the slip control system has stopped, it is first determined whether a speed ratio variation amount, due to the change-over of the vehicle speed used for speed change control from the estimated vehicle speed VSPFL to the sensor detected vehicle speed VSPSEN, is less than a permissible amount. When it is determined that the speed ratio variation amount is smaller than the permissible amount, the vehicle speed used for speed change control is changed over from the estimated vehicle speed VSPFL to the sensor detected vehicle speed VSPSEN. By performing this change-over, a sharp variation of the vehicle speed used for speed change control is suppressed, and a sharp variation of the speed ratio leading to shocks or slipping is suppressed.
Abstract:
A lock-up torque converter is equipped with a lock-up clutch. The lockup clutch may engage even when the vehicle is coasting (lock-up coasting). When an accelerator pedal is depressed in a stepwise manner during lock-up coasting, the lock-up clutch is temporarily disengaged. By setting the threshold value used for determination so that it is easier to determine that the accelerator pedal was depressed in a stepwise manner the lower the vehicle speed, the dual objectives of vibration suppression of the drive system and improvement of fuel cost-performance are realized.
Abstract:
A vehicle transmission control system in which a central control unit issues signals to an associated main drive clutch actuator and to ratio actuating means to effect changes in the operative ratio of an associated transmission in accordance with a predetermined shift point map. When the shift point map indicates that a ratio shift is appropriate, the system tests for fluctuations in the position of the an associated engine accelerator pedal and only actions the shift if the degree of fluctuation of the accelerator pedal position is judged acceptable. The acceptable level of accelerator pedal fluctuation preferably varies with engine speed.
Abstract:
A method for control of a preferably electro-hydraulically activated automatic transmission of a motor vehicle equipped with an internal combustion engine provides for prevention of upshifting, i.e. reduction in translation in and before a curve. The upshift prevention is initiated if pressure is removed quickly from the gas pedal in idle operation. The upshift prevention is cancelled if the vehicle does not drive through a curve after elapse of a certain time period after traction operation is recognized. If idle operation is again recognized during elapse of the time period, the upshift prevention is maintained for another time period. After termination of the upshift prevention, step by step adjustment of the gear level to the value determined by the shifting characteristic field takes place.
Abstract:
A vehicle includes a powertrain and a controller. The powertrain includes a transmission mechanically coupled to an electric machine and configured to transfer torque between a wheel and the electric machine. The transmission has a gearbox configured to establish gear ratios through a shift. The controller is programmed to, in response to an indication of an expected regenerative braking event having a timing falling within a shift window of the transmission, prevent a clutch of the transmission from disengaging until first occurrence of application of an accelerator pedal or removal of the indication to inhibit the shift prompted by a shift schedule of the gearbox.
Abstract:
Systems and methods for operating a transmission of a hybrid powertrain that includes a motor/generator are described. The systems and methods may permit or inhibit transmission shifting in response to objects or conditions in a vehicles travel path. Transmission shifting is not permitted when conditions indicate the possibility of excessive transmission shifting.
Abstract:
Systems and methods for managing shift changes of a multi-speed automatic transmission of a vehicle are provided. The multi-speed automatic transmission being capable of establishing a plurality of forward speed ratios. The vehicle may include a transmission shift selector having at least one operator selectable shift request input to request a shift change of the multi-speed automatic transmission. A control circuit operatively coupled to the multi-speed automatic transmission is provided which shifts the multi-speed automatic transmission from a first forward speed ratio to a second forward speed ratio in response to shift criteria. The shift criteria may be based on a plurality of operational characteristics related to the vehicle.
Abstract:
A road information acquisition unit (12a) acquires information about the road in a prescribed segment in front, a vehicle information acquisition unit (12b) acquires information about the vehicle (1), a velocity prediction unit (12c) predicts, on the basis of the road information and the information about the vehicle (1), the changes in the vehicle velocity that would be brought about in the prescribed segment in the case of travelling the prescribed segment in a first gear, and a shift control unit (12d) which maintains the first gear if the condition is satisfied that the predicted vehicle velocity exhibits a minimum value other than at the ends of the prescribed segment and the minimum value is greater than the delay speed, which is set to a value less than a predetermined velocity set as the velocity that would result from downshifting.