Patent ID: 8157129

Claim:
A volumetric feeder used for a powdery or granular material combination weigher provided with a plurality of raw-material-supplying hoppers and a corresponding plurality of scale units having respective weighing hoppers, the volumetric feeder comprising: a movable volumetric measure including a plurality of measure portions each having a predetermined constant volume and configured to move between a charging position adjacent a charging aperture of a raw-material-supplying hopper, at which a predetermined volume of powdery or granular material is charged, and a discharging position adjacent a charging aperture of a corresponding weighing hopper, at which the powdery or granular material is discharged to the corresponding weighing hopper; a selecting means for each measure portion, each of the plurality of selecting means being independently driven to selectively supply the powdery or granular material from one or more of the associated measure portions only to corresponding weighing hoppers that are associated with a subset of scale units selected from the plurality of scale units, the corresponding weighing hoppers associated with the subset of scale units having been used for a combination and emptied while powdery or granular material remains undischarged in other of the weighing hoppers; and wherein each measure portion is bounded by a selectively openable top side, a selectively openable bottom side, and an outer perimeter wall completely surrounding the predetermined volume, and wherein in the charging position the measure portion is configured to receive the predetermined volume of powdery or granular material through an opening in the top side of the measure portion while an opening in the bottom side of the measure portion is closed, and wherein in the discharging position the measure portion is configured to discharge the predetermined volume of powdery or granular material through the opening in the bottom side of the measure portion, while the opening in the top side of the measure portion is closed.