Oscillating settling tank raking device - with adjustable weights on shields pivoted to endless chains with ascending discharge

摘要

A raking device for rectangular setting tanks in sewage engineering consists of endless chains which are guided by deflection sprockets and carries raking flights. The flights are pivoted to the chains so that they can oscillate. In the horizontal part of the tank guides of horizontal rails are provided for the chain. The solids which settle at the bottom of the trough in the settling channel are moved by raking shields which can oscillate on pivots of endless chains. Adjustable weights can be added to the side arms of the shields. In the horizontal section, the chains are rigidly guided in rails. This saves the construction of a travelling bridge and the design of a tank strong enough that its rim can stand the weight of the bridge. The flights can deflect during starting (thus reducing the motor starting torque) and when encountering any obstacle.