DEVICE FOR FEEDING GRANULAR AND POWDERED MATERIALS IN DOSES, SYSTEM CONTAINING THE DEVICE FOR FEEDING GRANULAR AND POWDERED MATERIALA USED IN MIXING CARBON BLACK, AND A METHOD FOR CONTINUOUS MIXING WITH THE USE OF THE FEEDING DEVICE

摘要

Metering device for introducing controlled volumes of a powdered or granular material into a process such as extrusion compounding (90) comprises a horizontal turntable (21) onto which material is dropped at approximately the required input rate. The turntable is confined by a chamber (2) which can accommodate surges of excess material. The turntable has a thick rim (23) on its upper border with at least one opening (24) and which passes between the wall (3) of a surrounding block (30) and a marking piece (4) that covers part of the path of the rim and opposite which is a discharge outlet (5) into a chamber (6) in the equipment receiving the material. The material is positively transferred from (2) into (24) and from (24) into (6) by centrifugal effects, and the material transfer rate thereby a direct function of the volume of material contd. in (24) between (3) and (4), the number of openings (24) in the rim and the rate of rotation of (21). The material inlet chamber (2) and passage (6) pref. expand, to inhibit bridging. The turntable face features radial ribs (23) to promote radial flow into the opening(s) (24). One end(s) of each circumferential rim wall has a slight superficial groove (221) to induce an anticlogging effect alongside the wall of the entry chamber (31). Transfer from (6) to (90) may be ram assisted.