Sheet Material End Detection Mechanism, Roll Body, and Method for Producing Roll Body

Abstract

Provided is a sheet material end detection mechanism including: a sheet material information part indicating information on a sheet material wound around a core member in which a light passing part is formed; a reader configured to optically read the sheet material information part; and a detection unit configured to detect that the sheet material is used up. A forming part is attached to an outer surface of the core member and an inner surface of the sheet material. The sheet material information part is formed in a portion of the forming part corresponding to the light passing part. The detection unit detects that the sheet material is present when a read signal of the sheet material information part read by the reader is received and that the sheet material is used up when the read signal disappears.

1 . A sheet material end detection mechanism comprising:
 a roll body constituted by winding a sheet material around a tubular core member;   a holding unit configured to hold the roll body so as to allow the sheet material to be withdrawn;   a sheet material information part provided in the roll body and indicating information on the sheet material;   a reader configured to optically read the sheet material information part of the roll body held by the holding unit; and   a detection unit configured to detect that the sheet material is used up based on results of the reading by the reader, wherein   the core member has a light passing part through which light passes so as to enable the optical reading by the reader from inside to outside,   the roll body has a forming part located between an outer surface of the core member and an inner surface of the sheet material and used for forming the sheet material information part,   the sheet material information part is formed in a portion of the forming part corresponding to the light passing part,   the forming part is attached to the core member and the sheet material,   adhesive force between the sheet material and the forming part is larger than adhesive force between the core member and the forming part, and   the detection unit is configured to detect that the sheet material is present when a read signal of the sheet material information part read by the reader is received and that the sheet material is used up when the read signal disappears, during the withdrawing action to withdraw the sheet material from the roll body held by the holding unit.   
     
     
         2 . A roll body comprising:
 a tubular core member;   a sheet material wound around the core member; and   a forming part located between an outer surface of the core member and an inner surface of the sheet material and used for forming a sheet material information part indicating information on the sheet material, wherein   the core member has a light passing part through which light passes so as to enable optical reading from inside to outside,   the sheet material information part is formed in a portion of the forming part corresponding to the light passing part,   the forming part is attached to the core member and the sheet material, and   adhesive force between the sheet material and the forming part is larger than adhesive force between the core member and the forming part.   
     
     
         3 . A method for producing a roll body by winding a sheet material around a tubular core member,
 the core member having a light passing part through which light passes so as to enable optical reading from inside to outside, the method comprising:   a step of forming a sheet material information part indicating information on the sheet material, on a forming part used for forming the sheet material information part;   a step of attaching the forming part onto an outer surface of the core member so that the sheet material information part corresponds to the light passing part;   a step of attaching the forming part to a winding start portion of the sheet material with adhesive force larger than adhesive force between the core member and the forming part; and   a step of winding the sheet material around the core member.