Disclosed are power machines, and drive systems for use thereon, as well as methods of providing automatic gear shifting. The drive system includes a controller configured to implement automatic gear shifting. Gear engagement is determined following a gear shift, and a drive pump or other drive system components is automatically controlled to rotate a gearbox gear in first and second directions until the gear is properly engaged.

When an input torque becomes greater by a predetermined value or more due to an operation of increasing an amount of accelerator depression amount or the like during a gear shift, a controller for an automatic transmission updates a target gear shift characteristic value to a target gear shift characteristic value which is set when the gear shift is started with the input torque based on the input torque at the updating time, and performs gear shift control from a degree of progress in gear shift at the updating time based on the updated target gear shift characteristic value. Since the target gear shift characteristic value can be changed with respect to an increase in the input torque during the gear shift by this control, it is possible to prevent a decrease in durability of frictional engagement elements.

An electronic control unit updates a target gear shift characteristic value to a target gear shift characteristic value which is set at a gear shift start time with a first predetermined torque based on the first predetermined torque and performs gear shift control from a degree of progress in gear shift based on the updated target gear shift characteristic value, when an input torque becomes equal to or less than the first predetermined torque due to an accelerator returning operation or the like during a gear shift (during a power-on upshift). Accordingly, it is possible to perform stable gear shift control to cope with a decrease in input torque during the gear shift and to suppress occurrence of a shock.

A method is provided for checking a configuration safety of a coupling device for a gear box sliding gear. The gear box sliding gear is rotationally connected to a drive input shaft of the gearbox and is axially movable on the drive input shaft from an intermediate neutral position to either of two opposite positions of engagement with an idler pinion. The method defining a neutral configuration of the coupling device on based on a main information relating to the position of the slider gear and its movement setting, in which position the transmission of the torque to the wheel is effectively stopped, and in that the start of synchronization of the slider gear with a pinion is only allowed when the device is in this configuration.

In a vehicle in which a continuously variable transmission, which is connected to an electric motor via a clutch, is operated using oil pressure of an oil pump driven by the motor, erroneous engagement of the clutch is quickly determined. The vehicle has the motor serving as a vehicle driving source, the oil pump connected to the motor, the continuously variable transmission, the clutch interposed between the motor and the continuously variable transmission, a clutch control means for controlling the clutch such that the clutch enters into a completely-engaged, slip-engaged, or release state, and a vehicle control means for controlling the motor such that the motor rotates at a target rotation speed. Also provided is an erroneous engagement handling control means that executes torque adjustment control to decrease an output torque of the vehicle driving source when the clutch is determined to be in an erroneously completely engaged state.

Provided is a hydraulic oil control device having a shifting control unit configured to, in a case where, when upshifting is performed, a number of revolutions of an input shaft connected to a to-be-engaged clutch is higher than a number of revolutions of the engine, or a case where, when downshifting is performed, the number of revolutions of the input shaft is lower than the number of revolutions of the engine, supply the to-be-engaged clutch with a hydraulic oil having a pressure equal to or higher than a predetermined standby pressure, and then to supply the to-be-engaged clutch with the hydraulic oil having the standby pressure, and then configured to cause the to-be-engaged clutch to be engaged by supplying the to-be-engaged clutch with the hydraulic oil having a pressure higher than the standby pressure.

A mechanical supercharging system includes a stepped transmission that connects a crankshaft of an internal combustion engine with driving wheels, a centrifugal supercharger including a rotary drive shaft connected to the crankshaft, a variable speed ratio device that changes a speed ratio of the rotary drive shaft to the crankshaft, the variable speed ratio device being provided between the crankshaft and the rotary drive shaft; and a control device configured to control the speed ratio. The control device increases the speed ratio during the upshift operation more than the speed ratio before start of the upshift operation.

Vehicle control system and method provided to change speed ratio smoothly when switching a power transmission route from a route including a geared transmission to a route including a continuously variable transmission. Vehicle control system applied to a vehicle comprising: continuously variable transmission for changing speed ratio continuously is disposed between input shaft and output shaft; geared transmission is disposed parallel to the continuously variable transmission, and is adapted to establish speed ratio that cannot be established by continuously variable transmission; and friction clutch is brought into engagement to switch torque transmission route from a route including the geared transmission to a route including the continuously variable transmission. Vehicle control system configured to start speed change operation of continuously variable transmission before the friction clutch is brought into engagement completely when switching torque transmission route from the route including the geared transmission to the route including the continuously variable transmission.

A transmission includes an input shaft and an output shaft, the input shaft selectively accepting a torque input from a prime mover, and the output shaft selectively providing torque output to a driveline. A controller determines a shaft displacement angle representing an angle value of rotational displacement difference between at least two shafts of the transmission, and performs a transmission operation responsive to the shaft displacement angle.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. A shift actuator selectively couples the input shaft to the main shaft by rotatably coupling gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. An integrated actuator housing includes a single external power access for the shift actuator. A controller interprets a shaft displacement angle, determines if the transmission is in an imminent zero or zero torque region, and performs a transmission operation in response to the transmission in the imminent zero or zero torque region.