Fluid-friction clutch

摘要

A fluid-friction clutch for a cooling fan of an internal combustion engine, the clutch being fitted on the water-pump shaft which drives the impeller of a water pump for the internal combustion engine and being controlled by an expansion-type thermostat element which is located in a longitudinal bore through the water-pump shaft. Cooling water of the internal combustion engine is applied directly to the expansion-type thermostat element, this water being continuously conveyed through the longitudinal bore in the water-pump shaft by utilizing the pressure-difference created in the cooling water by the impeller of the water pump. In order to cool both the working chamber of the fluid-friction clutch and the clutch-bearing, a cooling line is arranged inside the working chamber and connected to the cooling-water circulation inside the longitudinal bore through the water-pump shaft.