A system, apparatus and method are provided for limiting operating speed at high temperatures of a self-propelled, agricultural product applicator having a hydraulic drive system including a pump supplying pressurized hydraulic fluid to a variable-displacement hydraulic motor operatively connected for propelling the applicator. A temperature sensor detects a temperature of the pressurized hydraulic fluid in the hydraulic system. A propel controller is operatively connected between the temperature sensor and the propulsion motor and configured for limiting displacement of the propulsion motor according to one or more predetermined de-rated conditions resulting in reduced motor speed, in accordance with a predetermined schedule, when predetermined motor de-rating activation temperature limits of the hydraulic fluid are detected by the temperature sensor. The controller is further configured for providing a de-rated condition warning signal prior to limiting displacement of the propulsion motor.

An automatic transmission where the control portion controls the adjustment solenoid valve so that the circulation hydraulic pressure equals to a second circulation hydraulic pressure higher than the first circulation hydraulic pressure when the rotational speed difference between the output rotational speed of the fluid transmission device and the rotational speed of the driving source is more than the predetermined rotational speed.

Under an abnormal determination, when a transmission gear stage is switched, a torque limit value is changed from a value before switching of the transmission gear stage to a value after switching thereof in a period in which this transmission gear stage is switched.

When an engagement-side clutch taking charge of rotation control in a downshift is the same as a rotation control clutch in the previous gear shift or a clutch of which the engagement has been switched in the previous gear shift, there is a likelihood that clutch hydraulic controllability will decrease and the clutch hydraulic controllability is secured by delaying start of the gear shift. It is possible to execute a gear shift which is a downshift without unnecessary waiting by setting a delay time by which the start of the gear shift is delayed depending on an accelerator depression amount such that the delay time is shorter when the accelerator depression amount is small than when the accelerator depression amount is large.

A method for operating an automatic transmission with resistance change in a control system of the automatic transmission includes detecting an electrical resistance increase in a control loop for a shift element actuator of the automatic transmission, adjusting an electrical current to the shift element actuator in response to the electrical resistance increase, and shifting the automatic transmission to a gear in which the shift element is in the open operating state. A related control device for an automatic transmission is also provided.

A variable-speed speed-up mechanism includes: an electric device which is configured to generate a rotational driving force and a planetary gear transmission device which is configured to change the speed of the rotational driving force transmitted from the electric device to a constant-speed input shaft and a variable-speed input shaft and transmit the rotational driving force to a target to be driven via an output shaft. The electric device includes a constant-speed electric motor including a constant-speed rotor which is configured to rotate the constant-speed input shaft of the planetary gear transmission device and a variable-speed electric motor including a variable-speed rotor which is configured to rotate the variable-speed input shaft of the planetary gear transmission device.

A method for operating an automatic transmission with resistance change in a control system of the automatic transmission includes detecting an electrical resistance increase in a control loop for a shift element actuator of the automatic transmission, adjusting an electrical current to the shift element actuator in response to the electrical resistance increase, and shifting the automatic transmission to a gear in which the shift element is in the open operating state. A related control device for an automatic transmission is also provided.

An actuation system comprises a plurality of actuators, a common power drive unit for driving the actuators and a transmission line transmitting drive from the common drive unit to the plurality of actuators. A clutch is arranged in the transmission line between the power drive unit and the plurality of actuators for selectively disconnecting the power drive unit from the plurality of actuators. At least one sensor is provided for sensing an abnormal load condition in the actuation system. The at least one sensor is operatively coupled to a clutch control which is configured such that when the at least one sensor senses an abnormal load condition, the clutch control is operative to disengage the clutch so as to disconnect the power drive unit from the plurality of actuators. A brake is operative to brake the actuators upon disengagement of the clutch.

Control systems and methods for a vehicle transmission initiate a shift operation of the transmission and, during the transmission shift operation, determine an acceleration of a torque generating system output shaft based on its measured rotational speed and determine an acceleration of the transmission output shaft based on its measured rotational speed, identify an error source using a transmission model that maps differences between the determined and target accelerations back to torque generating system error and/or transmission clutch torque error and, based on the identified error source, adjust the actuation of at least some of the plurality of clutches to compensate for the torque generating system error and/or transmission clutch torque error to mitigate or eliminate noise/vibration/harshness (NVH) caused by the transmission shift operation.

An actuation system comprises a plurality of actuators, a common power drive unit for driving the actuators and a transmission line transmitting drive from the common drive unit to the plurality of actuators. A clutch is arranged in the transmission line between the power drive unit and the plurality of actuators for selectively disconnecting the power drive unit from the plurality of actuators. At least one sensor is provided for sensing an abnormal load condition in the actuation system. The at least one sensor is operatively coupled to a clutch control which is configured such that when the at least one sensor senses an abnormal load condition, the clutch control is operative to disengage the clutch so as to disconnect the power drive unit from the plurality of actuators. A brake is operative to brake the actuators upon disengagement of the clutch.