| 摘要 |
In a control device (6) for an automatic motor vehicle gearbox with electro-hydraulically actuated gear-engaging elements (18), the gear-shift comfort during an upshift in tractive mode is improved by control of the hydraulic pressure. In a first phase of the shift, the fill phase, the hydraulic pressure is quickly brought to a desired variable using a large duty factor (duty cycle) of a PWM signal applied to a valve. In a second phase of the shift, in which the gearbox input torque passes from the gear shift element of the old gear to that of the new gear, the hydraulic pressure is also controlled by a large duty factor. And in a third phase of the shifting operation, the inertial phase, in which the decrease in the engine speed occurs, the hydraulic pressure is first quickly controlled to a desired variable and is then regulated. |
