Stirrer for liquids, or propeller for ships - esp. stirrer with hollow shaft used to inject air into liq. manure

摘要

Stirrer or propeller includes a hollow shaft which can be rotated, and carries stirrer- or propeller blades. In the hub of the shaft, and between adjacent blades is a hole covered by a curved baffle (30) to form a chamber with a cross-section which increases in a direction opposite to the direction of rotation of the shaft. Air is fed through the hollow shaft and travels into the liq. via the holes covered by the baffles. One edge of the baffle is pref. joined to a blade; and the curvature of the baffle pref. corresponds with that of an Archimedean spiral. Used e.g. in the stirring and treatment of manure, where air is fed into the manure to provide oxygen. In the case of a ship's propeller, aerial oxygen is continuously fed into the water.