摘要:
A system for controlling a machine with a continuously variable transmission includes a first control device configured to produce a first signal based on a first operator input and a second control device configured to produce a second signal based on a second operator input. The system also includes a control system configured to receive the first and second signals from the first and second control devices and generate a raw torque value based on the first and second signals. The control system is also configured to determine an output torque value based on the raw torque value and transmit the output torque value to the transmission to control the transmission.
摘要:
A system and method for variator control employs positively directed electronic make-up and flushing relief valves for more precise torque control of a hydraulic variator, especially during torque reversal, as well as improved cold weather operation. This can improve machine response during periods of severe torque change. The ability to more tightly control variator torque allows more precise torque management algorithms for power control and engine matching purposes. Moreover, the ability to positively control venting of the hydraulic circuit for purposes of fluid cooling allows for more consistent machine response regardless of ambient temperature.
摘要:
A system for controlling a machine with a continuously variable transmission includes a first control device configured to produce a first signal based on a first operator input and a second control device configured to produce a second signal based on a second operator input. The system also includes a control system configured to receive the first and second signals from the first and second control devices and generate a raw torque value based on the first and second signals. The control system is also configured to determine an output torque value based on the raw torque value and transmit the output torque value to the transmission to control the transmission.
摘要:
A method of dissipating power in a propelled machine having a hydromechanical transmission includes converting undesired power to retarding power, and driving an engine with at least a portion of the retarding power prior to substantially dissipating power with any other power-dissipating device.
摘要:
An apparatus for controlling a continuously variable transmission includes an input shaft driven by an engine, an output shaft, an operator input for generating speed commands and a controller operable to receive the speed commands and generate transmission ratio commands which control a ratio of a speed of the output shaft to a speed of the input shaft. Torque of the output shaft is limited in a torque limited region near zero speed of the output shaft and the transmission ratio command is modified in the torque limited region.
摘要:
A hydraulic motor system for improved frequency response includes a hydraulic variator having a pump and a motor, wherein the pump includes a variable angle swash plate, and the system further includes an electric actuator for controlling an angle or torque of the swash plate, thereby controlling the motor output characteristics. The electric actuator for controlling the variable angle swash plate may comprise a linear electric motor, ball screw drive or a rotary electric motor. In an example, the rotary electric motor tilts the swash plate by applying a torque to the swash plate at a point away from its tilt axis. In a further example, the rotary electric motor tilts the swash plate via a worm drive or ball screw drive.
摘要:
A system and method for optimizing machine performance using speed shaping in a machine having an engine and a drivetrain implementing engine underspeed module receives a throttle command requesting an increase in engine speed and transmits the throttle command to the engine. If the requested increase exceeds a predetermined function, the predetermined function is forwarded to the engine underspeed module as a speed standard. The engine underspeed module determines whether the actual engine speed attained by the engine is less than the speed standard by more than a predetermined gap value and, if so, reduces the power required by the drivetrain to avoid lugging of the engine.
摘要:
A variator torque control system adjusts a variator output so that the actual output torque of the variator closely matches an expected output torque. In an example, pressure values of an existing torque control map are supplemented in real time with calculated pressure supplement values based on the current operation of the variator. The pressure supplement value for each mapped pressure value may be derived based on a prior application of the same or another map value.
摘要:
A drivetrain for use in a mobile vehicle is disclosed. The drivetrain may have a combustion engine with a mechanical output, a ground engaging traction device, and a primary transmission unit. The primary transmission unit may be connected to transmit power from the mechanical output to the ground engaging traction device. The drive train may also have a hydraulic power assist unit operatively connected to the mechanical power output to selectively drive the combustion engine.
摘要:
A transmission assembly is disclosed. The transmission assembly includes a continuously variable transmission driven by an input shaft at an input speed, a mechanical transmission coupled to the continuously variable transmission for selecting a first gear range and a second gear range, an output shaft driven by the mechanical transmission at an output speed, and controller operable to receive a speed command and generate a transmission ratio is command which control a ratio of the output speed to the input speed, and generate a shift command which causes the mechanical transmission to shift from the first gear range to the second gear range. An upper transmission ratio limit defined by an engine lug limit. A lower transmission ratio limit is defined by an engine overspeed limit. The controller causes the transmission to execute a shift from the first gear range to the second gear range which causes an instantaneous change in output speed. The engine lug limit or the engine overspeed limit are adjusted to inhibit a subsequent shift from the second gear range to the first gear range. A method for controlling a transmission assembly is also disclosed.