| 摘要 |
PURPOSE:To improve the kneading effect of a thermoplastic material in an extruder, by using a screw and a cylinder of polygonal cross sections cut perpendicular to the screw shaft in the kneading zone wherein at least one of the screw and cylinder has a cross section formed from two or more concentric polygons with proper different phases. CONSTITUTION:The cross scetional shape of the screw 2 and the cylinder 1 constituting the kneading zone of an extruder are made a regular hexagon and a pseudo- regular dodecagon formed from the two concentric regular hexagons 6 and 7 of the same shape shifted 30 degrees, respectively. The angle alpha made by the neighboring sides of the pseudo-regular dodecagon is 60 degrees the same as in the case of the regular hexagon, therefore, it provides substantially the same deforming effect on the material to be kneaded as in the case of the regular hexagonal cross section. Furthermore, the frequency of deformation is twice that of the regular hexagonal cross section, thus irroving the kneading effect. |
