Sheet manufacturing apparatus, control method thereof, and sheet manufacturing method

A control method of a sheet manufacturing apparatus including

• a fibrillating unit that includes a rotor and fibrillates a raw material including fibers in a gas,
• an additive supply unit that includes a feeder and supplies an additive,
• a mixing unit including a blower with a rotating unit disposed downstream relative to the additive supply unit in a transport direction of a fibrillated matter fibrillated by the fibrillating unit, the rotating unit mixing the fibrillated matter and the additive supplied by the additive supply unit,
• a depositing unit that is disposed downstream relative to the rotating unit in the transport direction of the fibrillated matter and deposits a mixture mixed by the mixing unit,
• a web forming unit including a mesh belt that transports a deposited material deposited by the depositing unit and including a suction mechanism that sucks the deposited material to the mesh belt, the suction mechanism having a first air flow generation unit that generates an air flow in a direction crossing a deposition surface where the deposited material is deposited, and
• a controller,
• the control method comprising:
• controlling a rotation velocity of the rotating unit of the blower of the mixing unit, and further controlling at least one of a supply amount per unit time from the additive supply unit and a suction force of the suction mechanism, at the controller, to change granularity of a surface of the sheet, wherein
• a flow velocity of the air flow generated by the first air flow generation unit is changed by the controller.

A sheet manufacturing method comprising:

• a fibrillating step of fibrillating a raw material including fibers in a gas and obtaining a fibrillated matter;
• an additive supplying step of supplying an additive to the fibrillated matter at an additive supply unit includes a feeder;
• a mixing step of mixing the fibrillated matter and the additive by using a rotating unit of a blower of a mixing unit and obtaining a mixture, the rotating unit being disposed downstream relative to the additive supply unit in a transport direction of the fibrillated matter;
• a depositing step of obtaining a deposited material by depositing the mixture at a depositing unit disposed downstream relative to the rotating unit of the blower of the mixing unit in the transport direction of the fibrillated matter while sucking the mixture to a mesh belt by generating an air flow in a direction crossing a deposition surface where the deposited material is deposited;
• and
• controlling a rotation velocity of the rotating unit of the blower of the mixing unit, and further controlling at least one a supply amount per unit time from the additive supply unit and suction force to the mesh belt, to change a granularity of a surface of the sheet, wherein
• the suction force to the mesh belt is controlled by changing a flow velocity of the air flow generated in the direction crossing the deposition surface.