Patent ID: 8382923

Claim:
An apparatus for producing gypsum boards, comprising: a forming device forming a layered formation into a plate-like configuration by a forming pressure, the layered formation being constituted by an upper sheet of paper, a lower sheet of paper and a slurry continuously interposed between the sheets, and the forming device including: a forming gate defined by upper and lower plates which extend in a crossing direction with respect to a conveyance direction of the upper and lower sheets and which are in surface-to-surface contact with the layered formation under the forming pressure, so that the layered formation is passed through said gate to impose the forming pressure on the layered formation by the upper and lower plates, in order to stabilize a configuration and a thickness of the layered formation, the upper plate being divided into a fixed substrate plate and a movable plate separated from the fixed substrate plate, the fixed substrate plate being a metal plate with high rigidity, the movable plate being a metal plate with relatively low rigidity, and the movable plate being located below the fixed substrate plate substantially in parallel with the fixed substrate plate so as to be in surface-to-surface contact with the upper sheet of the layered formation; a plurality of actuators for up-and-down motion, are carried on and supported by the fixed substrate plate wherein each of the actuators locally applies an upward or downward load to said movable plate for a local deformation thereof owing to a deflection of the movable plate, so that the forming pressure acts on the layered formation by the locally deflected movable plate in surface-to-surface contact with the upper sheet of paper means for supporting a reaction force of each of the actuators by the fixed substrate plate.