| Patent application number | Description | Published |
|---|
| 20080269011 | System for controlling a machine with a continuously variable transmission - 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. | 10-30-2008 |
| 20080294318 | FEEDBACK ADJUSTMENT FOR OPEN-LOOP TORQUE CONTROL MAP - A variator torque control system and method utilize a hydraulic actuator to control the variator output via a torque control map, wherein the values of the torque control map are evaluated and modified during use of the map to improve map accuracy. In an example, errors in the map are evaluated to determine whether a system fault has occurred. | 11-27-2008 |
| 20080300103 | OPEN-LOOP TORQUE CONTROL WITH CLOSED-LOOP FEEDBACK - 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. | 12-04-2008 |
| 20090005914 | FEEDBACK ACCELERATION REDUCTION FOR FLUID SUPPLY VALVES - A system and method for controlling a variator operate to detect variator torques and/or internal pressures and generates a preliminary corrective command. The preliminary corrective command is transformed via a dynamic transform to account for system characteristics during transient operating conditions such as machine acceleration, such that the acceleration of the system during transient periods is not torque-limited by static torque-control map values. In an embodiment, the acceleration may be positive or negative, and in a further embodiment, braking is automatically applied in the case of negative requested power or desired machine retarding. | 01-01-2009 |
| 20090005941 | ANTI-HUNT SYSTEM AND METHOD FOR PARALLEL PATH VARIABLE TRANSMISSION - A system and method for largely controlling transmission gear ratio oscillation is disclosed. When shifts are executed substantially at synchronous points rendering hysteretic anti-hunting schemes impractical, the disclosed techniques in any combination thereof may allow for oscillation control via an overridable lock-out timer. For oscillation control during incline navigation and other similar loading scenarios, the transmission may be selectively locked if certain operational criteria are met. | 01-01-2009 |
| 20090156360 | PART-THROTTLE PERFORMANCE OPTIMIZATION - 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. | 06-18-2009 |
| 20090199814 | POWER-BASED UNDERSPEED CONTROL - A method of adjusting the operation of an engine-driven machine to avoid engine under-speeding entails converting a received speed or torque command into a power command. When an engine under-speed condition is sensed, the system performs underspeed correction in the power domain before converting the underspeed processed power command back into the units of the original domain. The converted underspeed processed power command is issued to the transmission or other component to alleviate the engine under-speeding condition. | 08-13-2009 |
| 20090298635 | Electric motor actuation of a hydrostatic pump - 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. | 12-03-2009 |
| 20100095665 | Hydrostatic pump and motor with improved torque reversal characteristics - 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. | 04-22-2010 |
