▎ 摘　　要

NOVELTY - The preparation chamber (1) has a main chamber and an auxiliary chamber. The outlet end of the main chamber, communicates with the inlet end of the auxiliary chamber. A part of the bottom surface of the preparation chamber, is recessed downward to form a liquid airtight tank (4). The outlet end of the main chamber and the inlet end of the auxiliary chamber, are both located below the liquid level of the liquid airtight tank. The outlet end of the auxiliary chamber, is provided with an elastic airtight component (8). USE - Preparation chamber e.g. closed chamber of scale preparation device of CVD deposited graphene (claimed). ADVANTAGE - The secondary sealing effect of the elastic airtight component, prevents the failure of the first seal caused by the changes in the level of the deionized water and the etching liquid when the preparation chamber is evacuated. DESCRIPTION OF DRAWING(S) - The drawing shows the schematic diagram of the internal structure of a large-scale preparation equipment for CVD-deposited graphene. Preparation chamber (1) Liquid airtight tank (4) Conveyor belt assembly (5) Thermal insulation material (6) Elastic airtight component (8)