The Mechanical Handling and Storing of Material

CHAPTER XVIII 'automatic feeding devices C. Kemble Baldwin, of Chicago, III., read an interesting paper on “ Automatic Feeders for Handling Material in Bulk,”1 of which the following is an extract. The illustrations of the devices are not intended to show the construction, but to illustrate the principles Fig. 270. Undercut-Gate Feeder. involved, so that they may be compared. The automatic feeder not only saves the expense of an attendant to adjust gates, but ensures a constant and regular feed, irrespective of the size of the material. Fig. 270 shows the under- cut-gate feeder, with a body either of cast iron or steel plate, pivoted near the top of the undercut gate, which is swung back and forth by a connecting rod from crank or eccentric. This type of feeder is best adapted to fine-sized, free-flowing material. As the feed is intermittent, the feeder is generally used in con- nection with chain or bucket conveyors, the strokes being timed to feed material between the flights, or into the buckets. The capacity may be changed by changing the length or the number of strokes. As the length of stroke is more easily changed, it is preferable to use a crank rather than an eccentric, as in practice the quick return of the eccentric has not been found of suffi- cient value to offset the great advantages of a crank with an adjustable throw. The lifting-gate feeder, shown in Fig. 271, also gives an intermittent feed, and is therefore principally used with a chain or bucket conveyor or elevator. The shoot is hinged, so that when down the material will flow out of the hopper, but when raised above the angle of flow of the material the discharge is stopped. The moving of the shoot may be accomplished by a connecting rod receiving motion from either crank or eccentric. This feeder will handle material regardless of size, but it must be free-flowing material, so that it will move by gravity when.the shoot is lowered to the angle of flow. The capacity may be adjusted by varying the number of strokes; also, in a measure, by increasing the length of the stroke, 1 Read before the American Society of Mechanical Engineers at the Washington Meeting, May 1909. 202