| 摘要 |
An electronic control system for a transmission in a work vehicle such as an agricultural tractor is disclosed herein. The system includes sensors for detecting the output speed of the vehicle engine, the output speed of the transmission and the vehicle ground speed. Command devices are available to the vehicle operator for generating command signals, such as for commanding the direction of movement, as well as forward and reverse gear ratios. A controller receives signals from the sensors and command devices, and controls engagement and disengagement of combinations of fluid clutches in the transmission to obtain desired gear ratios between the transmission input and output shafts. The command devices include an input device for generating transmission command signals, and the controller responds by selectively engaging the clutches to shift the transmission at a predetermined shift rate. The controller determines a commanded gear ratio based at least in part on the transmission command signals. When the commanded gear ratio differs from the current gear ratio by more than a predetermined number of gear ratios, the controller accesses a table stored in a memory circuit to determine a skip shift value associated with the current gear ratio and selectively engages the clutches to skip shift from the current gear ratio to the commanded gear ratio by a number of gear ratios determined by the accessed skip shift value.
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