The key sensing element is the spiral bimetal temperature sensor on the front cover, which senses the heat and deforms the control valve plate, thus controlling the silicone oil to enter the working chamber and adding the drive shaft and fan.
When the engine load increases and the coolant temperature rises, the high-temperature airflow blows on the bimetal temperature sensor, which causes the bimetal to be deformed by heating and drives the valve plate driving pin and the control valve plate to deflect at an angle. When the air temperature exceeds a certain temperature, the oil inlet hole is opened, and the silicone oil in the oil storage cavity enters the working chamber through this hole. The torque on the driving disk is transmitted to the clutch housing through the shear stress of silicone oil, which drives the fan to rotate at high speed.
Extended data:
Common faults of silicone oil fan clutch:
1. The spiral bimetal temperature sensor is broken, which causes the fan not to turn.
2. The fatigue failure of the spiral bimetallic temperature sensor leads to the high temperature sensing state, which leads to the failure of the fan to work in time and affects the engine performance.
3. The oil storage cavity and working cavity are not tightly sealed, and the loss of silicone oil affects the torque transmission.
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