Patent ID: 9545748
Date: 2017-01-17
CPC Classifications: B29C,B29K,B29L

Claim:
1. Method for stretch blow-molding containers, comprising the steps of: thermally conditioning a preform of a thermoplastic material along a transport path in the area of a heating section; placing the preform in a blow mold; applying a blowing pressure to the preform so that the preform, via an intermediate stage called a container bladder, subsequently develops into the container in the blow mold; monitoring development of the container bladder in the blow mold during deformation of the preform in the blow mold by measuring and evaluating, using a control device, at least two parameters during development of the container bladder, which at least two parameters characterize the temporal development of the container bladder, the measuring including making chronological measurements while the container bladder is being blow molded during the intermediate stage, the at least two parameters being selected from the group consisting of: contact of the container bladder with the blow mold measured using contact-sensitive sensors, contact of the container bladder with the blow mold measured by electric field measurement or optical sensors, pressure sequence, gas volume supplied to the container bladder, stretching speed, stretching force, and temperature in a material of the preform to be formed; adapting the measured parameter to a corresponding desired value by changing at least one adjusting variable that influences the deformation process in dependence on the evaluation of the development of the container bladder in the blow mold within a closed control circuit; and controlling development of the container bladder within the blow mold during formation of the container.