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.

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 relates to a method for resolving a tooth-on-tooth position of a positive-locking shifting element of an automated manual transmission, in which gear steps of the automated manual transmission are changed by means of a pressure-medium-actuated shift actuator. If, during a change of a gear step of the automated manual transmission, a tooth-on-tooth position occurs at the interlocking shifting element, then the control of the pressure-medium-actuated shift actuator is varied in such manner as to resolve the tooth-on-tooth position. A control unit for carrying out the method is also disclosed.

The present invention relates to a method for resolving a tooth-on-tooth position of a positive-locking shifting element of an automated manual transmission, in which gear steps of the automated manual transmission are changed by means of a pressure-medium-actuated shift actuator. If, during a change of a gear step of the automated manual transmission, a tooth-on-tooth position occurs at the interlocking shifting element, then the control of the pressure-medium-actuated shift actuator is varied in such manner as to resolve the tooth-on-tooth position. A control unit for carrying out the method is also disclosed.

A transmission includes a gearing arrangement configured to shift speed ratios by disengaging an off-going shift element and engaging an oncoming shift element and an electrohydraulic valve having an actuatable valve element configured to control an engagement state of the oncoming shift element. A controller is programmed to, during a shift of the transmission, in response to the off-going shift element disengaging and an expected ratio change not initiating, monotonically increase current to the valve to a maximum value to overcome frictional resistance on the valve element, and programmed to, in response to expiration of a timer and the ratio change still not initiating, send a repeating pattern of high and low current signals according to a duty cycle to overcome frictional resistance of the valve element.

A transmission includes a gearing arrangement configured to shift speed ratios by disengaging an off-going shift element and engaging an oncoming shift element and an electrohydraulic valve having an actuatable valve element configured to control an engagement state of the oncoming shift element. A controller is programmed to, during a shift of the transmission, in response to the off-going shift element disengaging and an expected ratio change not initiating, monotonically increase current to the valve to a maximum value to overcome frictional resistance on the valve element, and programmed to, in response to expiration of a timer and the ratio change still not initiating, send a repeating pattern of high and low current signals according to a duty cycle to overcome frictional resistance of the valve element.

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.

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 is operationally coupled to the shift actuator and a linear clutch actuator. The linear clutch actuator is a self-adjusting actuator, and the transmission includes a self-adjusting clutch.

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 is operationally coupled to the shift actuator and a linear clutch actuator. The linear clutch actuator is a self-adjusting actuator, and the transmission includes a self-adjusting clutch.

A fluid assembly in a hydraulic circuit, comprising one or more reservoirs configured to store fluid. The fluid assembly also includes a pump configured to transport the fluid in the hydraulic circuit and actuate a load from a transmission of a motor vehicle, a pressure accumulator configured to collect pressure built up by the pump and actuate the load, and a valve system configured to allow fluid communication of the load with the pump.