| 摘要 |
In a gearbox with hydraulically-operated multiple-disc clutches (11,12,13,14), particularly for vehicles, the hydraulic circuit for operating the clutches includes an auxiliary valve (29) for regulating the clutch operating pressure, which is arranged to prevent the pressure downstream thereof exceeding the minimum necessary for engaging the clutches as long as the pressure upstream thereof does not reach a predetermined value greater than the minimum value. The auxiliary valve (29) is also arranged to allow an increase in the downstream pressure which is gradual before the minimum value is reached and rapid when this minimum value is exceeded. |
