A milling machine includes a rotor drive transmission having a plurality of gears disposed between a prime mover and a cutting rotor. The rotor drive transmission is associated with a rotor transmission hydraulic circuit including a hydraulic gearshift actuator to engage the plurality of gears in one or more gear ratios and a gearshift directional control valve to direct hydraulic fluid to and from the hydraulic gearshift actuator. In occurrence of a fault condition, the rotor transmission hydraulic circuit includes a gearshift trapping valve to maintain hydraulic pressure in the hydraulic gear actuator and the engaged gear ratio of the rotor drive transmission.

The present invention addresses the problem of obtaining an electronic control device for a vehicular automatic transmission that suppresses sudden acceleration, sudden deceleration, and gear shift shock that occur when the transmission moves into a fail-safe mode due to the electronic control device stopping during a main CPU abnormality. An electronic control device 100 for a vehicular automatic transmission has: a main CPU 3 that performs gear shift control for the vehicular automatic transmission; and a sub-CPU 4 that detects abnormalities in the main CPU 3. When the sub-CPU 4 detects an abnormality in the main CPU 3 while the vehicle is traveling, the sub-CPU 4 stops the gear shift control executed by the main CPU 3. Next, when the control status of the vehicular automatic transmission is in a state of maintaining the gear position, the sub-PCU 4 continues the maintaining of the gear position; when the control status is in a state of changing the gear position, the sub-PCU 4 continues a gear shift operation for the gear position, and, instead of the main CPU 3, performs alternative control for maintaining the gear position after the gear position is changed. Subsequently, as a result of a stop in the traveling of the vehicle, the sub-PCU 4 finishes the alternative control and abnormally stops the electronic control of the automatic transmission.

A vehicular driving control system and a method for operating the same are provided, may include an information provider to provide information on a front road of a vehicle, a transmission controller to control gear shifting by predicting a condition on the front road based on the information on the front road, and a diagnosing device to diagnose a failure status by verifying matching with the information on the front road, and to restrict a predictive gear-shifting controlling operation of the transmission controller, according to a result of the diagnosing.

A hydraulic system for a vehicle transmission with at least two friction elements, the system comprising a first hydraulic circuit comprising a pump for supplying hydraulic fluid to the first hydraulic circuit. A flow restriction may be provided in the first hydraulic circuit between an output of the pump and a sump for providing leakage of hydraulic fluid into the sump. Further, a second hydraulic circuit comprising a second pump may be arranged, wherein the hydraulic pressure in the first circuit is higher compared to the second circuit. A flow control element operated using hydraulic pressure from the first circuit may be arranged for controlling flow/pressure in the second circuit. Further, the hydraulic system may be arranged for generating a line pressure, wherein an actuator for engaging a park lock system may be connected to the first hydraulic circuit for enabling direct actuation by means of the line pressure.

A working vehicle includes: a vehicle body; a linkage device configured to link a working device to the vehicle body; a prime mover provided on the vehicle body; a traveling device configured to cause the vehicle body to travel; a transmission device configured to transmit power from the prime mover to the traveling device and perform a speed change process to change a speed of the vehicle body; an increase-in-speed detection device configured to detect an increase in speed of the vehicle body; and a speed change restraint unit configured such that, during the speed change process performed by the transmission device, when the increase in speed detected by the increase-in-speed detection device has become equal to or greater than a threshold, the speed change restraint unit stops the speed change process performed by the transmission device.

A hydraulic pressure control device of a vehicle driving device, the hydraulic pressure control device includes a range switcher having a first signal solenoid valve capable of supplying a first signal pressure and a spool switchable between a first position reached via the first signal pressure and a second position reached via a biasing force of a biasing member.

A shift by wire control for a multi-speed vehicle transmission is provided. The control includes a shift by wire shift valve in fluid communication with other shift valves and clutch trim valves to provide double blocking features in the neutral range and a reverse range. The shift by wire valve is configured with multiple differential areas to provide failure modes for all forward ranges.

A control device provided in a gear shifting device includes an electronic control unit. The electronic control unit determines whether an abnormality of the gear shifting device has occurred, performs a fail-safe process of switching the frictional engagement element corresponding to an abnormality to a disengaged state and fixing the gear shift ratio of the gear shifting device when it is determined that an abnormality has occurred, determines whether the abnormality has been relieved based on a behavior of an input signal at the time of operating a drive device of the frictional engagement element corresponding to an abnormality on condition that the frictional engagement element is maintained in the disengaged state after it is determined that the abnormality has occurred, and releases the fail-safe process when it is determined that the abnormality has been relieved.

A control device provided in a gear shifting device includes an electronic control unit. The electronic control unit determines whether an abnormality of the gear shifting device has occurred, performs a fail-safe process of switching the frictional engagement element corresponding to an abnormality to a disengaged state and fixing the gear shift ratio of the gear shifting device when it is determined that an abnormality has occurred, determines whether the abnormality has been relieved based on a behavior of an input signal at the time of operating a drive device of the frictional engagement element corresponding to an abnormality on condition that the frictional engagement element is maintained in the disengaged state after it is determined that the abnormality has occurred, and releases the fail-safe process when it is determined that the abnormality has been relieved.

Non-inverted park lock systems and methods include an engine controller configured to control an engine of a vehicle in communication with a separate transmission controller via a controller area network (CAN), wherein the transmission controller is configured to control a transmission of the vehicle; and a conductor connecting the engine controller to a park lock solenoid disposed in the transmission and configured to move a park pawl to engage/disengage park. The engine controller keeps the park pawl disengaged from park during a power loss malfunction at the transmission controller and the transmission controller keeps the park pawl disengaged from park during a power loss malfunction at the engine controller by maintaining hydraulic pressure in the transmission at a threshold level until park is requested via the shifter.