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 through hole 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. The sheet material information part extends from a portion corresponding to the through hole at an end of the sheet material wound around the core member to a portion adjacent to the through hole on an inner surface of the core member. 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around a tubular core member;   a holding unit configured to hold the roll body so as to allow the sheet material to be withdrawn;   a sheet material information part provided in the roll body and indicating information on the sheet material;   a reader configured to optically read the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   a through hole is formed in the core member to pass therethrough in an inward-outward direction,   the sheet material information part is formed to extend from a portion corresponding to the through hole at an end of the sheet material wound around the core member to a portion adjacent to the through hole on an inner surface of the core member, 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; and   a sheet material wound around the core member, wherein   a through hole is formed in the core member to pass therethrough in an inward-outward direction, and   a sheet material information part indicating information on the sheet material is formed to extend from a portion corresponding to the through hole at an end of the sheet material wound around the core member to a portion adjacent to the through hole on an inner surface of the core member.   
     
     
         3 . The roll body according to  claim 2 , wherein
 the through hole has a smaller area than the sheet material information part.   
     
     
         4 . A method for producing a roll body by winding a sheet material around a tubular core member,
 a through hole being formed in the core member to pass therethrough in an inward-outward direction, the method comprising:   a step of winding the sheet material around the core member; and   a step of forming a sheet material information part indicating information on the sheet material to extend from a portion corresponding to the through hole at an end of the sheet material wound around the core member to a portion adjacent to the through hole on an inner surface of the core member.