An automatic transmission that includes a speed change mechanism including a gear mechanism that can attain a plurality of shift speeds, and a plurality of friction engagement elements that are selectively engaged to attain each shift speed in the gear mechanism; a hydraulic control device that can regulate engagement pressures to be supplied to hydraulic servos of the plurality of friction engagement elements and that can supply lubricating oil that lubricates the speed change mechanism; and a control unit that sends a command about the engagement pressures to the hydraulic control device to control engagement states of the plurality of friction engagement elements.

A transmission system avoids activation of a sailing functionality in a vehicle. The transmission system is configured for automatic gear-shifting in an automatic mode and manual gear-shifting by a user in a manual mode. The transmission system includes a user input device configured for manually changing the operational mode between the automatic and manual modes. The transmission system includes a transmission control unit for determining a recommended gear in the automatic and manual modes. In the manual mode, an operating gear of the transmission system is detected by the transmission control unit. A change of the operational mode from manual to automatic by means of the user input device is detected, and if the detected operating gear in the manual mode when changing to automatic mode is lower than the recommended gear, the sailing functionality in the automatic mode is deactivated.

A transmission system avoids activation of a sailing functionality in a vehicle. The transmission system is configured for automatic gear-shifting in an automatic mode and manual gear-shifting by a user in a manual mode. The transmission system includes a user input device configured for manually changing the operational mode between the automatic and manual modes. The transmission system includes a transmission control unit for determining a recommended gear in the automatic and manual modes. In the manual mode, an operating gear of the transmission system is detected by the transmission control unit. A change of the operational mode from manual to automatic by means of the user input device is detected, and if the detected operating gear in the manual mode when changing to automatic mode is lower than the recommended gear, the sailing functionality in the automatic mode is deactivated.

A hydraulic control system for a transmission is provided with a power source, two drive wheels, a power transmission device, a hydraulic pump, a main valve, and a controller. The power transmission device is configured to be set to a plurality of speed stages. The main valve is disposed between the hydraulic pump and the power transmission device and adjusts the main pressure of hydraulic fluid supplied from the hydraulic pump to the power transmission device. The controller controls the main valve. The controller sets the main pressure to a pressure value derived by correcting a clutch holding pressure of the set speed stage based on a load applied to each of the drive wheels.

The control method for a constant speed running of a vehicle performs a vehicle speed control for downshifting the gear position of the automatic transmission when the acceleration/deceleration of the vehicle is larger than the determination value during the constant speed running control. In the control method, the automatic transmission includes a plurality of gear positions that can be downshifted during the constant speed running control, and among the plurality of gear positions, the determination value between the gear positions having a relatively large difference in the gear ratio between the gear positions is set to be larger than the determination value between the gear positions having a relatively small difference in the gear ratio between the gear positions.

The control method for a constant speed running of a vehicle performs a vehicle speed control for downshifting the gear position of the automatic transmission when the acceleration/deceleration of the vehicle is larger than the determination value during the constant speed running control. In the control method, the automatic transmission includes a plurality of gear positions that can be downshifted during the constant speed running control, and among the plurality of gear positions, the determination value between the gear positions having a relatively large difference in the gear ratio between the gear positions is set to be larger than the determination value between the gear positions having a relatively small difference in the gear ratio between the gear positions.

Disclosed are a method and device for controlling the state switching of a fluid torque converter, a vehicle and a storage medium, the method including: obtaining a target instruction when the torque converter of the vehicle is in a locked state, the target instruction triggering a change in the torque transmission direction of a transmission system of the vehicle; obtaining a state parameter, and determining whether the current vehicle is in a target operating condition according to the state parameter; and if the current vehicle is in the target operating condition, switching the fluid torque converter to an open state, and switching the torque converter back to the locked state after maintaining the open state for a preset period of time.

Disclosed are a method and device for controlling the state switching of a fluid torque converter, a vehicle and a storage medium, the method including: obtaining a target instruction when the torque converter of the vehicle is in a locked state, the target instruction triggering a change in the torque transmission direction of a transmission system of the vehicle; obtaining a state parameter, and determining whether the current vehicle is in a target operating condition according to the state parameter; and if the current vehicle is in the target operating condition, switching the fluid torque converter to an open state, and switching the torque converter back to the locked state after maintaining the open state for a preset period of time.

Various methods and systems are provided for a shift assembly for a vehicle transmission. In one example, a shift assembly for a transmission includes a first barrel cam including a first cam track; a second barrel cam arranged coaxially with the first barrel cam and including a second cam track; a first motor configured to drive the first barrel cam independent of the second barrel cam; and a second motor configured to drive the second barrel cam independent of the first barrel cam.

There is provided a shift device for a straddle-type vehicle that is configured to cause a transmission device to perform a shift change in accordance with rotation of a shift shaft. The shift device includes: a shift lever provided with an operation portion that is configured to receive a shift operation; a shift sensor provided on the shift shaft so as to be integrally rotatable with the shift shaft; and a shift rod that couples the shift lever and the shift sensor. The shift sensor is configured to detect the shift operation on the shift lever in accordance with a movement of the shift rod. The operation portion and the shift sensor are positioned at the same side in a manner of sandwiching the shift rod.