Patent ID: 7312408

Claim:
A powdery- or granular-material weighing apparatus for weighing a powdery or granular material within a predetermined allowable range of a target weight, the powdery- or granular-material weighing apparatus comprising: a plurality of scale units each for weighing a powdery or granular material, the plurality of scale units constituting a combination weigher which discharges the weighed material from the scale units which constitute a combination that attains, among totals for arbitrary combinations of a predetermined number of weighed values in the scale units, a total that is within the predetermined allowable range of the target weight; and a weighing hopper for weighing the material to be weighed; wherein each of the scale units is provided with a powdery- or granular-material supplying means for supplying the powdery or granular material to the scale units at a constant flow rate; wherein the powdery- or granular-material supplying means is selected from the group consisting of a belt feeder, a disk feeder, a screw feeder, a rotary feeder, an auger, a pinch valve, a wing feeder, a slat valve and a roll feeder; and weighing hopper comprises a cylindrical portion and a pinch valve for opening/closing a lower portion of the cylindrical portion.