The gas in polymer melt during injection molding includes various chemical substances that leave deposits on the vent, which leads to a clogged vent. The predictive maintenance of the vent is necessary to prevent the sudden generation of defects and the unexpected downtime of the process due to vent clogging. Hence, it is necessary to monitor the state of the vent. In this study, we propose cavity-gas-pressure (CGP) and cavity-gas-temperature (CGT) sensors as monitoring sensors and evaluate the feasibility of the sensors for monitoring vent clogging. The CGP and the CGT sensors measure the pressure and the temperature changes of the cavity gas respectively when the gas is compressed at the end of the filling. To examine the monitoring capability of the sensors, three sets of tests were conducted: a sensitivity test, an influence test of processing conditions, and a reliability test in a long-cycle run. The sensors were installed in a spiral mold with an interchangeable vent block of various depths in the experiments. Although the CGP and the CGT sensors exhibited sufficient sensitivity to detect vent depth differences, the CGP sensor showed higher sensitivity. In the influence test, processing conditions, such as the injection speed, metering value, melt temperature, and cooling time were examined with respect to PE and TE. In the reliability test in a long-cycle run, only the CGP sensor was tested. The CGP sensor produced a reliable result over 550 cycles, which proved that the sensor is a feasible sensor for monitoring vent clogging.

注塑过程中聚合物熔体中的气体包括各种化学物质，这些化学物质会在排气孔上留下沉积物，从而导致排气孔堵塞。必须对排气孔进行预测性维护，以防止由于排气孔堵塞而突然产生缺陷和意外停机。因此，有必要监视通风口的状态。在这项研究中，我们提出了腔体气体压力（CGP）和腔体气体温度（CGT）传感器作为监测传感器，并评估了用于监测通风口堵塞的传感器的可行性。当气体在填充结束时被压缩时，CGP和CGT传感器分别测量腔体气体的压力和温度变化。为了检查传感器的监视能力，进行了三组测试：灵敏度测试，加工条件的影响测试，以及长周期运行中的可靠性测试。在实验中，将传感器安装在具有不同深度的可互换排气模块的螺旋模具中。尽管CGP和CGT传感器显示出足够的灵敏度以检测排气孔深度差异，但CGP传感器显示出更高的灵敏度。在影响试验中，检查了相对于PE和TE的注射速度，计量值，熔融温度和冷却时间等加工条件。在长时间运行的可靠性测试中，仅测试了CGP传感器。CGP传感器在550个周期内产生了可靠的结果，这证明该传感器是监测通风口堵塞的可行传感器。在实验中，将传感器安装在具有不同深度的可互换排气孔的螺旋模具中。尽管CGP和CGT传感器显示出足够的灵敏度以检测排气孔深度差异，但CGP传感器显示出更高的灵敏度。在影响试验中，检查了相对于PE和TE的注射速度，计量值，熔融温度和冷却时间等加工条件。在长时间运行的可靠性测试中，仅测试了CGP传感器。CGP传感器在550个周期内产生了可靠的结果，这证明该传感器是监测通风口堵塞的可行传感器。在实验中，将传感器安装在具有不同深度的可互换排气模块的螺旋模具中。尽管CGP和CGT传感器显示出足够的灵敏度以检测排气孔深度差异，但CGP传感器显示出更高的灵敏度。在影响试验中，检查了相对于PE和TE的注射速度，计量值，熔融温度和冷却时间等加工条件。在长时间运行的可靠性测试中，仅测试了CGP传感器。CGP传感器在550个周期内产生了可靠的结果，这证明该传感器是监测通风口堵塞的可行传感器。在影响试验中，检查了相对于PE和TE的注射速度，计量值，熔融温度和冷却时间等加工条件。在长时间运行的可靠性测试中，仅测试了CGP传感器。CGP传感器在550个周期内产生了可靠的结果，这证明该传感器是监测通风口堵塞的可行传感器。在影响试验中，检查了相对于PE和TE的注射速度，计量值，熔融温度和冷却时间等加工条件。在长时间运行的可靠性测试中，仅测试了CGP传感器。CGP传感器在550个周期内产生了可靠的结果，这证明该传感器是监测通风口堵塞的可行传感器。