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 controls the shift actuator with actuating and opposing pulses, and 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.

A traveling work vehicle includes a gear-shifting control unit that outputs a gear-shifting control command to a main gear-shifting apparatus for shifting gears without cutting off power transmission, a sub gear-shifting apparatus for shifting gears by cutting off power transmission, and a first operation unit and a second operation unit that provide gear-shifting, upshifting or downshifting, operation commands to the gear-shifting control unit. The gear-shifting control unit has a first travel control section that generates a gear-shifting control command for shifting gears in the main gear-shifting apparatus in response to the gear-shifting operation command from the first operation unit in a work traveling mode, and a second travel control section that generates a gear-shifting control command for shifting gears in the sub gear-shifting apparatus in response to the gear-shifting operation command from the second operation unit in the work traveling mode.

A traveling work vehicle includes a gear-shifting control unit that outputs a gear-shifting control command to a main gear-shifting apparatus for shifting gears without cutting off power transmission, a sub gear-shifting apparatus for shifting gears by cutting off power transmission, and a first operation unit and a second operation unit that provide gear-shifting, upshifting or downshifting, operation commands to the gear-shifting control unit. The gear-shifting control unit has a first travel control section that generates a gear-shifting control command for shifting gears in the main gear-shifting apparatus in response to the gear-shifting operation command from the first operation unit in a work traveling mode, and a second travel control section that generates a gear-shifting control command for shifting gears in the sub gear-shifting apparatus in response to the gear-shifting operation command from the second operation unit in the work traveling mode.

A method to control a road vehicle for the execution of a multiple downshift in a drivetrain provided with a servo-assisted transmission; the control method comprises the steps of: detecting a condition of slowing down of the road vehicle and, simultaneously, detecting a driver's request for a multiple downshift; carrying out, in succession, a plurality of downshifts while the road vehicle is slowing down and in an autonomous manner regardless of further interventions of the driver; determining a duration of a shift time interval; and carrying out each downshift following a first downshift when said shift time interval has exactly elapsed since the previous downshift.

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. A controller controls the shift actuator utilizing an actuating pulse and an opposing pulse.

A transmission in which multiple shift forks are moved by a shared lead groove of a shift drum has an improved degree of freedom of design of an internal combustion engine as well as an improved degree of freedom of layout of shift forks. The transmission includes multiple shift forks having engaging protrusions that engage with a shared lead groove. At least one shift fork among the multiple shift forks has an opening angle α around a drum rotation center line of a shift drum between a boss center line as a cylindrical center line of a cylindrical boss that is axially supported by a fork shaft of the shift fork, and a fork action part of the engaging protrusion on which the shared lead groove acts in accordance with rotation of the shift drum.

A transmission in which multiple shift forks are moved by a shared lead groove of a shift drum has an improved degree of freedom of design of an internal combustion engine as well as an improved degree of freedom of layout of shift forks. The transmission includes multiple shift forks having engaging protrusions that engage with a shared lead groove. At least one shift fork among the multiple shift forks has an opening angle α around a drum rotation center line of a shift drum between a boss center line as a cylindrical center line of a cylindrical boss that is axially supported by a fork shaft of the shift fork, and a fork action part of the engaging protrusion on which the shared lead groove acts in accordance with rotation of the shift drum.

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. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. A shift control circuit operates a shift actuator using a first opposing pulse command and a first actuating pulse command, and releases pressure with shift actuating and opposing volumes of the shift actuator upon determining a shift completion event.

Disclosed is a method for operating a multi-speed vehicle transmission having a plurality of shift elements (A, B, C, D, E) for engaging the gears of the vehicle transmission. The method includes decoupling between an input (AN) and an output (AB) of the vehicle transmission in a neutral gear, and coupling the input (AN) and the output (AB) of the vehicle transmission in a drive gear for propelling the vehicle by closing at least one shift element (B). At least one transmission state is determined when the neutral gear is engaged, where a shift element (D) for a reverse gear of the vehicle transmission is closed at least partially if the transmission is in a state with increased drag losses when the neutral gear is engaged.

Disclosed is a method for operating a multi-speed vehicle transmission having a plurality of shift elements (A, B, C, D, E) for engaging the gears of the vehicle transmission. The method includes decoupling between an input (AN) and an output (AB) of the vehicle transmission in a neutral gear, and coupling the input (AN) and the output (AB) of the vehicle transmission in a drive gear for propelling the vehicle by closing at least one shift element (B). At least one transmission state is determined when the neutral gear is engaged, where a shift element (D) for a reverse gear of the vehicle transmission is closed at least partially if the transmission is in a state with increased drag losses when the neutral gear is engaged.