Improved Apparatus for Separating Chaff, Grain or other Materials of Different Specific Gravities.

摘要

28,087. House, H. Dec. 2. Disk-supported-blade fans; paddle centrifugal fans; impeller blades; regulating or controlling. -Apparatus for separating chaff, grain, &c. by means of an air current passing up through a shoot 3, Fig. 3, into which the material is fed from a hopper 4, is provided with means for maintaining a steady blast of air from the fan or blower irrespective of variations in the speed of the fan shaft. The fan blades 21 are mounted on loose arms or supports on the shaft 12, and driven by means of adjustable springs attached to the shaft and the blades. The inlet ports 18 at the ends of the drum casing may be opened or closed by means of louvers 19, Fig. 5. The outer louver of each set is carried by a sleeve 19a fixed to the shaft 12, and is adapted to slide across the inner one until a pin 23a on the inner louver engages with the end of a slot 23 in the outer louver. The inner louver of each set is attached to the fan arm or runner 20, and is slotted at its upper end to receive a pin on the next inner louver. Louvers 25, Fig. 8, may be hinged or otherwise mounted radially round each end opening of the fan casing; the louvers are held in a normal open position by means of springs 27, and are closed by the extra inrush of air when the speed of the fan increases. The louvers may be mounted at the larger end of a bell mouth fixed over the end opening of the casing. The fan blades 21, Fig. 3, may be pivotally mounted between the arms 28 on gudgeons placed off the centre lines of the blades, and carry projecting arms 29 with adjustable weights 30, which, when the fan is running above the normal speed, act against springs to tilt or feather the blades. Or the blades may be connected by cords which pass over pulleys on the fan arms to weights which, under the action of centrifugal force, slide on the fan arms and move the blades nearer to or farther from the fan shaft.