| 摘要 |
PROBLEM TO BE SOLVED: To provide an improved control system for a viscous fluid coupling dealing successfully with an idle condition at stop time. SOLUTION: When a vehicle engine is operated at a low speed, when a rotational speed of a fan exceeds a predetermined speed limit value, an input signal 29 relating to a coupling, for moving a value member to a closed position, is corrected. In this way, generation of an overfill condition is reduced, undesirable fan noise is decreased when the engine is again accelerated. Engine speed is detected, when the detected speed can be operated in an excessive slip heat region, a required fan speed is compared with a lower limit in the heat slip region. When the required fan speed exceeds the limit value, the input signal 29 relating to the coupling is corrected in accordance with a control input like an engine temperature, for operating the coupling in a safe upper or lower part of the slip heat region. |
