INJECTION DEVICE AND RESIN INJECTION METHOD

摘要

As an injection screw (2) applies pressure, a pressure maintenance plunger (22) is moved backward by the pressure of a resin to flow the resin into a pressure maintenance path (9) and pressurize the resin in a resin path (6) (primary pressure maintenance). A shutoff plunger (12) is closed to pressurize the resin in the resin path (6) and the pressure maintenance path (9) by the pressure maintenance plunger (22) (secondary pressure maintenance). Further, the shutoff plunger (12) is opened to move the pressure maintenance plunger (22) forward until the tip thereof projects into the resin path (6) and to discharge all the resin in the pressure maintenance path (9) to the resin path (6), so as to maintain the resin with respect to the pressure maintenance path (9) on the injection screw (2) side than the shutoff plunger (12).