To provide a sheet former capable of suitably regulating the thickness of a sheet forming body in a width direction in response to factors changing with time. A sheet former includes at least one vessel which stores slurry as a raw material, a wire cylinder immersed in the slurry inside the vessel and making sheets from solid components in the slurry while being rotated, and a sheet-forming amount regulator which regulates an amount of the solid components for making sheets by the wire cylinder in a width direction in accordance with a thickness of a sheet forming body in the approximately width direction formed for making sheets by the wire cylinder.

A sheet manufacturing apparatus includes a rotatable drum unit that includes an opening section having a plurality of openings on a surface thereof and a cylindrical section having no opening; a material supply unit that is provided to supply a material containing fibers to the drum unit by airflow; and a forming unit that forms a sheet by using the material passing through the openings, in which at least one of the drum unit and the material supply unit has a diffusion section in which airflow is diffused further on a downstream side than on an upstream side in a supply direction of the airflow.

A sheet manufacturing apparatus includes a rotatable drum unit that includes an opening section having a plurality of openings on a surface thereof and a cylindrical section having no opening; a material supply unit that is provided to supply a material containing fibers to the drum unit by airflow; and a forming unit that forms a sheet by using the material passing through the openings, in which at least one of the drum unit and the material supply unit has a diffusion section in which airflow is diffused further on a downstream side than on an upstream side in a supply direction of the airflow.

To provide a sheet former capable of suitably regulating the thickness of a sheet forming body in a width direction in response to factors changing with time. A sheet former includes at least one vessel which stores slurry as a raw material, a wire cylinder immersed in the slurry inside the vessel and making sheets from solid components in the slurry while being rotated, and a sheet-forming amount regulator which regulates an amount of the solid components for making sheets by the wire cylinder in a width direction in accordance with a thickness of a sheet forming body in the approximately width direction formed for making sheets by the wire cylinder.