Fibrous body accumulating device and estimation method

A fibrous body accumulating device comprising:

• a drum having a porous screen, the drum introducing a material including fibers and releasing the material to outside of the drum via the porous screen;
• a housing that houses the drum;
• a detection section disposed on the housing and detecting a presence of the material in the drum;
• at least one first processor constituting an estimation section that is electrically connected to the detection section and estimates an amount of the material in the drum based on a detection frequency at which the detection section detects the material;
• and
• a data storage in which data of a calibration curve showing a relationship between the detection frequency and the amount of the material in the drum are stored, wherein
• the estimation section calculates information on the detection frequency and estimates the amount of the material in the drum with reference to the calibration curve.