Controlling method of extrusion amount

Abstract

Abstract PURPOSE:To permit the uniform extrusion of molten resin even when conditions other than extrusion amount are changed by a method in which the extrusion amount is calculated from the pressures of resin right before the inlet of die and at the outlet of a screw, and the revolving number of the screw is controlled in such a way as to make the extrusion amount coincide with a target value. CONSTITUTION:The internal pressure of a screw 8 is detected by a resin pressure detector 9 provided right before the inlet of the screw 2 and a resin pressure detector 12 attached to a cylinder 7 at the tip of the screw 8, and the viscosity of molten resin is calculated. The extrusion amounts are calculated from the calculated value and the measured values by the detector 9, and the revolving number of the screw 8 is controlled such that the extrusion amount agrees with a target extrusion amount. In calculating viscosity, the viscosity obtained by other testers for physical properties is stored in advance, and the viscosity is then compared with the viscosity obtained from the resin pressure at the tip of the screw to estimate the viscosity to be used when the extrusion amount from die is calculated.

Inventors

• 👤 Yukio Tamura
• 👤 幸夫 田村
• 👤 Yasuhiro Okumoto
• 👤 奥本　康寛
• 👤 Iwao Miyake
• 👤 三宅　岩夫

Bibliographic Details