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:
Jan. 05, 2021
Filed:
Mar. 21, 2017
Dowa Thermotech Co., Ltd., Tokyo, JP;
Kazuya Sasaki, Aichi, JP;
Takahiro Fujita, Shizuoka, JP;
DOWA THERMOTECH CO., LTD., Tokyo, JP;
Abstract
In a door structure of a heat treatment furnace performing a heat treatment of a workpiece, there are provided: a first opening member and a second opening member in which workpiece passing ports where the transferred workpiece passes are formed; and a sheet shutter, the sheet shutter is provided with a winding portion and a shutter portion, the shutter portion is disposed between the first opening member and the second opening member, the shutter portion is provided with a first sheet portion which covers the workpiece passing port of the first opening member and a second sheet portion which covers the workpiece passing port of the second opening member at a time that the shutter portion is closed, and it is configured that a gas storage portion is formed between the first opening member and the second opening member at the time that the shutter portion is closed.