A control system for a transmission reverser having an output gear, a forward disconnect device, a first reverse disconnect device, and a second reverse disconnect device includes one or more controllers with processing and memory architecture configured to execute control logic to control the transmission reverser in a forward mode and a reverse mode. In the forward mode, the one or more controllers command the first reverse disconnect device to disengage and the forward disconnect device to engage to rotate the output gear in a forward direction. In the reverse mode, the one or more controllers command the first reverse disconnect device to engage and the second reverse disconnect device to engage to rotate the output gear in a reverse direction.

A transmission calibration tool automatically generates a detailed gearbox model based on a user input transmission topology description. During transmission calibration, the tool accepts inputs from transmission speed and torque sensors and estimates component torques for each gear element and each shift element. Following a shift or other transmission event, the calibration tool plots the component torques as a function of time, permitting the calibration engineer to better understand what is occurring during the event, and thus reducing the time required for calibration. The calibration tool also adapts several transmission component models and outputs the adapted models to provide insight into actual transmission component behavior.

A transmission controller of a toroidal continuously variable transmission includes a gain setting unit that adjusts a gain of closed-loop control for calculating a target value of a roller position in accordance with a change in a rotation speed of a disc in a first rotation speed range and a second rotation speed range higher than the first rotation speed range. The gain setting unit changes, in the first rotation speed range, the gain so that sensitivity of the closed-loop control decreases with an increase in the rotation speed, and changes, in the second rotation speed range, the gain so that a rate of decrease in the sensitivity of the closed-loop control with the increase in the rotation speed is smaller than that in the first rotation speed range.

A transmission controller of a toroidal continuously variable transmission includes a gain setting unit that adjusts a gain of closed-loop control for calculating a target value of a roller position in accordance with a change in a rotation speed of a disc in a first rotation speed range and a second rotation speed range higher than the first rotation speed range. The gain setting unit changes, in the first rotation speed range, the gain so that sensitivity of the closed-loop control decreases with an increase in the rotation speed, and changes, in the second rotation speed range, the gain so that a rate of decrease in the sensitivity of the closed-loop control with the increase in the rotation speed is smaller than that in the first rotation speed range.

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 control device for an automatic transmission includes a continuously variable transmission mechanism, a torque converter, a target transmission ratio calculation unit, a feedback control unit, and a phase compensation unit. The torque converter has a lock-up clutch. The target transmission ratio calculation unit is configured to calculate a target transmission ratio based on a travelling state. The feedback control unit is configured to perform feedback control based on an actual value indicative of a state of the continuously variable transmission mechanism. The phase compensation unit is configured to perform phase lead compensation of the feedback control based on the travelling state. The phase compensation control unit is configured to halt the phase lead compensation when an unstable travelling state of a vehicle is detected. The phase compensation control unit is further configured to release the lock-up clutch when the phase lead compensation is halted.

A control device for an automatic transmission includes a continuously variable transmission mechanism, a torque converter, a target transmission ratio calculation unit, a feedback control unit, and a phase compensation unit. The torque converter has a lock-up clutch. The target transmission ratio calculation unit is configured to calculate a target transmission ratio based on a travelling state. The feedback control unit is configured to perform feedback control based on an actual value indicative of a state of the continuously variable transmission mechanism. The phase compensation unit is configured to perform phase lead compensation of the feedback control based on the travelling state. The phase compensation control unit is configured to halt the phase lead compensation when an unstable travelling state of a vehicle is detected. The phase compensation control unit is further configured to release the lock-up clutch when the phase lead compensation is halted.

A method to control a road vehicle provided with a servo-assisted transmission during a slowing down phase; the control method generally includes, when the servo-assisted transmission is in an automatic operating mode, the steps of: calculating, assuming that a pressing of the brake pedal remains constant, an opening time interval needed to allow the road vehicle to reach an opening speed at which a clutch of the servo-assisted transmission is definitively opened; calculating a number of downshifts that can be carried out in the opening time interval based on a time needed to carry out a downshift; scheduling the downshifts to be carried out in order to get from the current gear engaged in the servo-assisted transmission to an opening gear with which the clutch of the servo-assisted transmission is definitively opened, so as to carry out no more than the number of downshifts that can be carried out in the opening time interval; and carrying out the scheduled downshifts.

A method to control a road vehicle provided with a servo-assisted transmission during a slowing down phase; the control method generally includes, when the servo-assisted transmission is in an automatic operating mode, the steps of: calculating, assuming that a pressing of the brake pedal remains constant, an opening time interval needed to allow the road vehicle to reach an opening speed at which a clutch of the servo-assisted transmission is definitively opened; calculating a number of downshifts that can be carried out in the opening time interval based on a time needed to carry out a downshift; scheduling the downshifts to be carried out in order to get from the current gear engaged in the servo-assisted transmission to an opening gear with which the clutch of the servo-assisted transmission is definitively opened, so as to carry out no more than the number of downshifts that can be carried out in the opening time interval; and carrying out the scheduled downshifts.

A gearbox with multiple planetary gear sets having the same type of center gears includes a planetary gear set, a planetary gear set structure, an input end, an output end and a locking end, and brakes (8). The gearbox adopts at least three planetary gear sets having the same type of center gears (sun gears) or three planetary gear sets having the same type of center gears (ring gears) to form a star-connected planetary gear set structure. A planet carrier (7) is used as the input end, any of the center gears (1) is used as the output end, and the remaining center gears (2, 3) are each used as a locking end. The gearbox adopts at least two brakes (8), each of the brakes (8) connected to a locking end. The brakes (8) are controlled by a gear shift control device to be in any of a braking state, a half-braking state and a non-braking state. The gearbox controls the gear by controlling the braking of the brakes (8).