A vehicle includes an engine and a transmission having an input shaft operably coupled to the engine, an output shaft operably coupled to wheels of the vehicle, a primary pump, and a secondary pump. The primary and secondary pumps are each configured to supply pressurized fluid to a valve body of the transmission. A controller is programmed to, in response to a loss of pressure of the primary pump and a speed of the output shaft exceeding a first threshold, shift the transmission to a neutral state, energize the secondary pump once the transmission is in the neutral state, and command the engine to idle speed.

Some embodiments are directed toward a transmission having a torque input and output, drive members selectively engageable for sequentially changing gear ratio between the torque input and output, the transmission also having a shaft with a shifting feature. The transmission includes a drum having a track around its outer perimeter and arranged such that torque can be transferred by rotating the shaft, the drum capable of being moved along the length of the shaft, a biasing mechanism for urging the drum towards a rest position along the length of the shaft, and a drive member selector member provided in operative relation to the track, wherein by rotating the shaft the drive member selector member can be selectively urged into contact with a first drive member for drivingly engaging therewith in a first torque connection or into contact with a second drive member for drivingly engaging in a second torque connection.

Some embodiments are directed toward a transmission having a torque input and output, drive members selectively engageable for sequentially changing gear ratio between the torque input and output, the transmission also having a shaft with a shifting feature. The transmission includes a drum having a track around its outer perimeter and arranged such that torque can be transferred by rotating the shaft, the drum capable of being moved along the length of the shaft, a biasing mechanism for urging the drum towards a rest position along the length of the shaft, and a drive member selector member provided in operative relation to the track, wherein by rotating the shaft the drive member selector member can be selectively urged into contact with a first drive member for drivingly engaging therewith in a first torque connection or into contact with a second drive member for drivingly engaging in a second torque connection.

A method of operating a motor vehicle drive-train having a drive aggregate, a group transmission and a drive output. The aggregate can couple an input shaft of the transmission which includes main, splitter and range groups. To carry out a shift, a target gear and target rotational speed of the aggregate are calculated for the shift to be carried out. After the initiation of the shift a load reduction is first carried out, then a group of the transmission is disengaged in order to shift the transmission to neutral, after which a group of the transmission is synchronized and to shift out of neutral, the synchronized group is engaged, and then the load is again built up. Initiation of the shift, after calculating the target gear and the target rotational speed, occurs at a point in time when complete performance of a shift is not yet possible.

A method of operating a motor vehicle drive-train having a drive aggregate, a group transmission and a drive output. The aggregate can couple an input shaft of the transmission which includes main, splitter and range groups. To carry out a shift, a target gear and target rotational speed of the aggregate are calculated for the shift to be carried out. After the initiation of the shift a load reduction is first carried out, then a group of the transmission is disengaged in order to shift the transmission to neutral, after which a group of the transmission is synchronized and to shift out of neutral, the synchronized group is engaged, and then the load is again built up. Initiation of the shift, after calculating the target gear and the target rotational speed, occurs at a point in time when complete performance of a shift is not yet possible.

A working vehicle of this invention includes a main speed change structure that includes a continuously variable speed change structure such as an HMT structure and a multi-speed speed change structure capable of switching between a first power transmission state with a first gear ratio and a second power transmission state with a second gear ratio providing a higher speed than the first gear ratio. A control device causes the continuously variable speed change structure to be accelerated to a forward travel side in accordance with an accelerating operation of a speed change operation member in a forward travel direction, and causes the multi-speed speed change structure to be changed from a first power transmission state to a second power transmission state when the rotational speed of the speed change output shaft reaches a switching speed set to exceed a work speed range.

A working vehicle comprises: 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 method of controlling a drive device of a construction machine with a split transmission, which is at least coupled, at an input side, to a drive force source and, on the output side, with a drive range change transmission so as to set at least two shiftable drive ranges. The method includes a detection step (S1) for detecting drive dynamic requests for operation of the construction machine and a determination step (S2) for determining whether a drive dynamic request with an increased drive dynamic is present. If a drive dynamic request with increased drive dynamics is determined, then a shifting step (S4) is executed for shifting the drive range change transmission from a second, of the at least two drive ranges, to a first of the at least two drive ranges, to achieve increased driving dynamics of the construction machine.

A method of controlling a drive device of a construction machine with a split transmission, which is at least coupled, at an input side, to a drive force source and, on the output side, with a drive range change transmission so as to set at least two shiftable drive ranges. The method includes a detection step (S1) for detecting drive dynamic requests for operation of the construction machine and a determination step (S2) for determining whether a drive dynamic request with an increased drive dynamic is present. If a drive dynamic request with increased drive dynamics is determined, then a shifting step (S4) is executed for shifting the drive range change transmission from a second, of the at least two drive ranges, to a first of the at least two drive ranges, to achieve increased driving dynamics of the construction machine.

A transmission is subject to thermal management to prevent damage or failure due to overheating. Sensors can be employed to capture characteristics of a transmission, such as fluid temperature or pressure. Further, a predictive model can be invoked to predict characteristics based on current and future conditions. Characteristics can be compared with a threshold for intervention. A thermal mitigation strategy can be generated and initiated when characteristics satisfy the threshold. The thermal mitigation strategy can specify various actions to dissipate heat, including altering shift control logic and triggering mechanical devices that can increase airflow, reduce air temperature, or both surrounding the transmission.