Process and installation for the manufacture of pencils

Abstract

In the course of the process of manufacturing pencils the polymer binding material is at first melted in a lead extruder (19) in order to manufacture the lead. To the melted polymer material is then added via a loading extruder (2) a mixture of additives in powder form such as colors, gliding and adhesive substances. After intensive mixing of the components in the lead extruder (1) a lead profile (13) is extruded which is cooled in a first cooling range (3) to the point where, upon entering the coating nozzle (6), it is not fully plastic anymore but also not completely cold. Through the coating extruder (4) and (5) the appropriate materials are introduced for the formation of the pencil coating. In the course of the subsequent second cooling range (8) the pencil profile is cooled down completely and after passing the withdrawal station (11) it is cut in a sawing station (12).

Dependencies are inferred from the claim text.