| 摘要 |
In a continuous-feed thermomolding machine a foil is advanced in a transport direction at a constant travel speed through a heat station where it is exposed to a heat source such that each piece of the foil is exposed for a predetermined residence time. When the machine is stopped, a shield is positioned in the station between the foil and the source so that substantially no heat is imparted to the foil from the source. The machine is started by accelerating the foil to the travel speed while simultaneously and synchronously accelerating the shield opposite to the travel direction such that, as the shield fully retracts from the station, the foil reaches the travel speed and, before the shield has fully retracted from the station, every piece of the foil in the station exposed by the retracting shield is exposed to the source for the residence time.
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