| 摘要 |
PURPOSE:To increase or decrease static pressure caused between a nozzle unit and a band, by using a damper to control the ejected quantity of gas from one of the gas outlet ports of the nozzle unit depending on the band. CONSTITUTION:When the thickness of a metal band 1 is large, a damper 6 is opened so that the metal band is floatingly supported by the static pressure of gas ejected from both gas outlet ports 3a, 3b. When the thickness of the metal band 1 is small, the damper 6 is displaced to reduce the inflow of the gas into a chamber 4b so that some of the gas ejected from the outlet port 3a flows as shown by a streamline (a) but the rest of the gas has its flow changed by a small quantity of ejected gas from the other outlet port 3b and makes a streamline (b) coming at a large incident angle into contact with the metal band 1. |
