| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a more universal alternative flow rate control method of compressed air for a preliminary blow in acknowledgment of the execution of the switch control, via a timer, etc. of flow rates in the prior art by using, within lines for supplying compressed air for a preliminary blow, proportional-flow-rate valves capable of freely selecting flow rate control patterns.SOLUTION: A preliminary blow is executed by using lines 20 through 23 for supplying compressed air for a preliminary blow and electromagnetic valves 44 and 45 and by switching ON/OFF the electromagnetic valves 44 and 45 in relation to each of points provided by equally dividing one molding cycle into a desired number so as to vary volumes of air supplied from the compressed air supply lines 20 through 23. It accordingly becomes possible to execute a preliminary blow by using universal electromagnetic valves and to provide a hollow-molding method capable of meeting the market need for a universal flow rate control method. Since the flow rate switch points are set in terms of equally divided points of one molding cycle, the handling is equivalent to that of a general parison thickness adjustment by a parison controller, and the time for ascertaining molding conditions can be abbreviated since settings become easy-to-understand and simple.</p> |
