| 摘要 |
PURPOSE:To respond to the change of back pressure by cutting the part of the fixed screw of a screw shaft in the periphery of the screw shaft and connecting the formed interval parts by the spring screw wound around the screw shaft. CONSTITUTION:The interval parts of a fixed screw 2 are connected by a spring like flight 3. The spring like flight 3 is wound around a screw shaft 1 to be made slidable with respect to shaft 1 and both end surfaces thereof are welded (w) to the fixed screw 2. An extruded synthetic resin receives back pressure from a breaker and the spring like flight 3 is slid in the direction shown by an arrow (x) by the back pressure to limit the extrusion amt. from the breaker and the resin is smoothly extruded. When back pressure is too small, the resin pushes the spring like flight 3 in the direction shown by an arrow Y to act so as to increase the extrusion amt. of the resin. |
