Dynamic classifier with hollow shaft drive motor

摘要

A dynamic classifier for a coal pulverizer has an improved drive mechanism which is mounted on top of a pulverizer and concentric with the classifier axis of rotation and is directly controllable. The drive mechanism is a variable-speed DC or AC electric motor having a hollow motor shaft. The motor can produce classifier rotor rotational speeds of between 50 and 200 rpm. The classifier rotor is supported from the hollow motor shaft. A coal feed pipe passes through the hollow motor shaft and classifier rotor shaft into the pulverizer.