In a viscous clutch, the power transmission is performed thanks to the viscous fluid located inside the clutch frame.

In new Euro 6 vehicles, the requirements regarding consumption and emissions have become increasingly strict. In relation to the cooling system, it is utterly important to reduce the time of clutch disengagement to deactivate the fan in those conditions in which it is not necessary to cool the engine.

The viscous clutch is the mechanism in charge of the power transmission between the vehicle engine and the fan of the cooling system. In most modern clutch designs, which are electronically controlled, apart from transmitting the movement to the fan, the clutch is also capable of controlling its speed at any time.

The fan is a fundamental element in the cooling system of a vehicle.

In some references of viscous clutch shafts, it is essential to machine threaded holes to ensure the correct assembling of the clutch to the vehicle.

The viscous clutch is a fundamental element of the cooling system in commercial vehicles. This component often undergoes great workloads to face the demanding cooling requirements of this type of vehicles.

As we have demonstrated in previous posts, the shaft of an electromagnetic viscous clutch is responsible for withstanding the control coil and the clutch frame where the fan is assembled, as well as connecting both the clutch and the vehicle. That is why the manufacturing tolerances of this component are very low.

The activation of this clutch is performed by a bimetal, in other words, by two assembled alloys with different expansion coefficients.

In viscous clutches with electromagnetic activation, it is very frequent for the ECU to receive a signal from the clutch indicating the fan rotational speed. This process is carried out thanks to the shared work of the hall effect sensor, located in the inner part of the control coil, and the magnetic ring.

Currently, it is necessary for new commercial vehicles to meet the Euro VI standards, which deal with restrictions regarding fuel consumption. For this reason, all vehicle components that affect fuel consumption directly must achieve a performance as optimal as possible. These components include the fan clutch of the cooling system..