| 摘要 |
PURPOSE:To improve the yield of the metal to be deposited by evaporation and the working efficiency of an installation with a device for plating continuously a metal by vacuum deposition onto a steel hoop by suppressing the reevaporation of the metal subjected to the vacuum deposition. CONSTITUTION:A steel hoop 1 is conducted via a vacuum sealing device 31, etc. to a vacuum vessel 2 in which a low pressure is maintained. The evaporating metal, for example, Zn vapor 5, from an evaporation vessel 4 is plated by vapor deposition on said hoop in the stage when the hoop is guided by a roll 3. The hoop is again conducted via a high pressure sealing device 6, etc. to the high pressure side. The vapor 5 everges off the roll 3. Inner ducts 12 heated by heaters are provided to the arc-shaped covers 10, 11 provided in the inlet of the roll 3 and are connected to the sealing bar 13 of the device 6. The Zn 8 evaporating again from the hoop 1 is thus suspended in the ducts 12 without vapor deposition. The reevaporation is eliminated when the partial pressure of the Zn vapor attains the satd. vapor pressure P1 at the reevaporation temp. of the solid Zn in the hoop 1. The reevaporation is kept suppressed even if a large amt. of the plated hoop 1 passes through the inside of the ducts 12 after the attainment of the pressure P1 and therefore the yield of Zn is improved and the working efficiency of the installation is improved as well. |
