Article conformity discriminating apparatus for an injection-molding

Abstract

An article conformity discriminating apparatus for an injection molding machine is capable of automatically discriminating the conformity of articles with accuracy without using a conforming article sample. In molding cycles for mass production of articles executed according to optimum molding conditions of a mold file read from a shared memory (105), an actual resin pressure detected by a pressure sensor (4) is periodically sampled according to an output of an address generator (118), while a reference resin pressure sampled in the same sampling period or a corresponding sampling period on a pressure transition pattern, in a conforming article molding process for determining the optimum molding conditions made before the mass production of the articles, is read from the shared memory, (105) by a processor (114), and the actual resin pressure is compared with the reference resin pressure. If the absolute value of the difference between the values falls outside an allowable range, a defective sample counter value is incremented. When a hold process ends, a conforming article signal is sent if the counter value indicating the frequency of improper actual resin pressure generation is not greater than an allowable frequency, whereas a defective article signal is sent if the counter value exceeds the allowable frequency.