Fan blade on a fan

摘要

The invention relates to a fan blade on a fan, which is used especially for ventilation in tunnelling and underground. Instead of a narrow gap between the blades and the fan housing enclosing the fan blades, the blades are provided at their ends with end plates and a greater clearance is maintained between the end plates and the fan housing. In this way the risk of any contact between the fan blade and the fan housing and hence the danger of sparking is greatly reduced without losses in delivery capacity, owing to a pressure equalisation on each blade. The end plates in fact prevent this pressure equalisation to approximately the same extent as a narrow gap previously provided between each blade and the fan housing.