An electric power generation controller for use in an aircraft is a controller of an electric power generating system configured such that: a manual transmission changes speed of rotational power of an aircraft engine; a continuously variable transmission changes the speed of the rotational power which has been changed in speed by the manual transmission; and the continuously variable transmission transmits the rotational power to an electric power generator. The electric power generation controller includes: a manual transmission control section configured to, when a predetermined shift condition is satisfied, control the manual transmission to switch a gear stage of the manual transmission; and a continuously variable transmission control section configured to, when the shift condition is satisfied, control the continuously variable transmission to such a side that fluctuation of an output rotational frequency of the manual transmission by the switching of the gear stage of the manual transmission is canceled.

A wheeled work vehicle includes: a transmission transmitting the rotational power of a traveling hydraulic motor to wheels; a traveling control valve having an interruption position that interrupts supply of hydraulic fluid from a hydraulic pump to the traveling hydraulic motor; a shift changeover valve that shifts the speed stage of the transmission by the position of the shift changeover valve being selectively switched; and a controller that controls the traveling control valve and the shift changeover valve. The controller switches the traveling control valve to the interruption position, then switches the position of the shift changeover valve such that the speed stage of the transmission is shifted to the low speed stage, and switches the traveling control valve from the interruption position to an original position side before the switching in a case where the controller shifts the transmission from the high speed stage to the low speed stage.

A transmission is subject to gear shift management that provides for shifting gears in a controlled manner in order to provide for a simplification of part and reduction in system complexity. In particular, a range synchronizer component can be replaced with a simplified range jaw clutch, without incurring a requirement for an installation of other components such as a motor generator or starter-generator.

A high performance synchronous transmission to be used aboard a motorcycle for transmitting the motion generated by an engine to a driving wheel, between a crankshaft and a hub shaft parallel therebetween and perpendicular to the median plane of the motorcycle, comprising on the crankshaft a centrifugal clutch, for the automatic engagement of the first speed above a predetermined rotation regime, and a driving pulley apt to transmit the motion through a subsequent kinematic chain, is provided with a coupling between crankshaft and driving pulley which connects them directly, by determining with its own engagement the exclusion of said centrifugal clutch, said coupling being controlled in disengagement when a control lever is in active position.

A wheeled work vehicle includes: a transmission transmitting the rotational power of a traveling hydraulic motor to wheels; a traveling control valve having an interruption position that interrupts supply of hydraulic fluid from a hydraulic pump to the traveling hydraulic motor; a shift changeover valve that shifts the speed stage of the transmission by the position of the shift changeover valve being selectively switched; and a controller that controls the traveling control valve and the shift changeover valve. The controller switches the traveling control valve to the interruption position, then switches the position of the shift changeover valve such that the speed stage of the transmission is shifted to the low speed stage, and switches the traveling control valve from the interruption position to an original position side before the switching in a case where the controller shifts the transmission from the high speed stage to the low speed stage.

A continuous variable transmission (CVT) hydraulic pressure control device includes: a pressure regulation valve regulating an operation pressure of oil supplied to a friction element of a forward-rearward device; and a switch valve to respectively switch oil discharge paths through which the oil supplied to the friction element is discharged, respectively by a pilot pressure from the pressure regulation valve and an elastic force of a return spring. In particular, the oil discharge paths switched by the switch valve have oil flow resistances different from each other.

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 work machine control system includes an operational input portion that accepts an input operation to change a position of acceptance, maintains the position of acceptance when there is no input operation accepted, and provides an operation command in accordance with change in position of acceptance, an operational force providing portion that provides a plurality of operational forces in correspondence with an amount of change of the position of acceptance, a transmission portion that changes a speed of rotation provided from a drive source to transmit resultant rotation to a drive wheel, and a controller that controls the transmission portion based on a travel speed of the drive wheel in accordance with the operation command.

A shift control apparatus for a vehicle automatic transmission to be provided in a vehicle that includes a hydraulic transmission device having a lockup clutch, an engine, an input shaft connected to the engine through the hydraulic transmission device, and drive wheels. The shift control apparatus includes a shift-down control portion configured, when a shift-down operation is executed to establish a first gear position by releasing a second engagement device, during running of the vehicle in a driven state with a second gear position being established with engagement of the second engagement device, to increase a torque of the engine so as to increase an input rotational speed as a rotational speed of the input shaft through the lockup clutch that is placed in an engaged state, and to release the lockup clutch before the input rotational speed reaches a synchronous speed of the first gear position.

An electronic control unit engages two of friction engagement elements provided in an automatic transmission in a neutral range. The electronic control unit disengages one of the two friction engagement elements engaged in the neutral range at the time of starting gear stage switching of an auxiliary transmission from a low-speed gear stage to a high-speed gear stage in the neutral range, and re-engages the friction engagement element that has been disengaged when determining that the gear stage switching has been completed.