| 摘要 |
PURPOSE:To obtain titled screw which is composed of two kinds of multiflights of a forward direction and a flight of a reverse direction and a single flight of the forward direction, having a specific depth of a screw groove, without impairing physical properties of raw resin provided with uniform quality and good appearance. CONSTITUTION:When a screw 10 is assembled into a specific cylinder and rotated and raw resin material is supplied, resin is rapidly melted and kneaded at the first flight part G having multiflights 11-13 which are shaped in a forward direction to convey the resin forward. Then, resin is perfectly melted, kneaded and also receives a dispersing action at the second flight part H having multiflights 11', 12' of the forward direction and the third flight part I which has multiflights 11'', 12'' of a reverse direction to convey resin backward and further homogenized and extruded at a screw part J having a single flight of the forward direction. The depth of the screw froove of the first-third multiflights is 6-12% of a screw diameter. |
