| 摘要 |
PURPOSE:To remove irregularity of quality of a molded article by a method wherein when resin pressure in a mold has reached any set value, operation is changed from the resin injecting and filling process to the pressure retaining and resin filling process and the resin pressure in the pressure retaining and resin filling process is controlled so that it shows any set secular pattern. CONSTITUTION:The pressure in B-part of an injecting cylinder 5 is controlled by the accumulator 11 and the servo valve 12 so that the resin pressure in C-part of the mold 1 varies according to the set pattern P(t) during the pressure retaining and resin filling process. The pressure pattern in the pressure retaining and resin filling process is determined by the signal P0(t) sent from the pressure setter 8, this signal P0(t) is sent to the comparator 17, the pressure P(t) in C-part of the mold 1 is sent to the comparator 17 through the pressure sensor 13, these pressures are compared and as a result the electrical signal drives the servo valve 12 through the amplitude 7. |
