Patent ID: 8758670
Filing Date: 2014-06-24
Classification: B29C,B29K

Abstract:
1. A method for blow molding containers, comprising the steps of: subjecting a preform made of a thermoplastic material to thermal conditioning along a conveyance path in a heating line; molding the preform into a container in a blow mold by the action of blowing pressure; measuring a wall thickness, after the container has been blow molded, at at least one height level of the container; supplying a control system with a preassigned value for the wall thickness as a setpoint value and with the measured wall thickness as an actual value; and presetting, using the control system, a value of at least one parameter that affects the blowing process as a function of a difference between the setpoint value and the actual value, wherein the value of at least one parameter that affects a supply of blowing gas is preset as a correcting variable by the control system and the presetting of the value of the parameter is based on a blowing process simulation model implemented in the control system, further including, in addition to the parameters affecting the supply of blowing gas, controlling heating temperature, carrying out the control as a cascade control, and controlling the temperature in an outer closed-loop and controlling the blowing gas parameter in an inner closed-loop.