The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 30, 1987
Filed:
Sep. 11, 1985
Heizaburo Furukawa, Hiroshima, JP;
Kanji Wake, Hiroshima, JP;
Yoshio Shimozato, Hiroshima, JP;
Kenichi Yanagi, Hiroshima, JP;
Mitsuo Katoh, Hiroshima, JP;
Tetsuyoshi Wada, Hiroshima, JP;
Norio Tsukiji, Sakai, JP;
Takuya Aiko, Sakai, JP;
Toshiharu Kittaka, Sakai, JP;
Yasuji Nakanishi, Sakai, JP;
Mitsubishi Jukogyo Kabushiki Kaisha, , US;
Nisshin Steel Co., Ltd., , US;
Abstract
For vacuum deposition plating steel strip, a vacuum deposition plating apparatus is used including an inlet-side vacuum sealing device provided in front of a vacuum deposition plating chamber, with an inlet-side inactive gas replacement chamber provided between the inlet-side vacuum sealing device and an annealing furnace. An outlet-side vacuum sealing device is provided at the rear of the vacuum deposition plating chamber, with an outlet-side inactive gas replacement chamber provided between the outlet-side vacuum sealing device and the atmosphere. An inactive gas circulating/purifying device circulates an inactive gas from vacuum chambers of both the vacuum sealing devices to atmospheric pressure chambers of both the vacuum sealing devices and removes water, oil and oxygen from the inactive gas. Oxygen and hydrogen in the inactive gas are regulated to provide 60 ppm or less of oxygen and 0.2 to 2.0% of hydrogen, and also to regulate the dew point of the inactive gas to -50.degree. C. or less. Further, a pressure P.sub.1 in the annealing furnace, a pressure P.sub.2 in the inlet-side inactive gas replacement chamber, and a pressure P.sub.3 in the outlet-side inactive gas replacement chamber are maintained at atmospheric pressure or more. A value of P.sub.1 -P.sub.2 can be kept at 0 mmAq or more, and the concentration of hydrogen in the inlet-side inactive gas replacement chamber is held to 2.0.degree. or less.