Patent ID: 7694964
Filing Date: 2010-04-13
Classification: B41J,B65H,G03G

Abstract:
1. A sheet material information detection apparatus comprising: an impact force application unit for applying an impact force to a sheet material; an impact force detection unit for detecting the impact force applied by the impact force application unit; an abnormality sensing unit for sensing abnormality of the sheet material entering a space between the impact force application unit and the impact force detection unit; and a retraction unit for allowing at least one of the impact force application unit and the impact force detection unit to retract in a direction in which the at least one of the impact force application unit and the impact force detection unit is moved away from one of the sheet material and a transport path for the sheet material in a case where the abnormality sensing unit senses the abnormality, wherein the abnormality sensing unit comprises a sheet material presser unit and a push-in sensing unit for sensing that the sheet material presser unit is pushed in by the sheet material, and the sheet material presser unit supports a displacement member that causes displacement by contact with the sheet material, wherein when a state exists where the sheet material pushes up the displacement member a distance sufficient to close an electrical contact for a first predetermined period of time, or when the sheet material pushes up the displacement member a sufficient amount to close an electrical contact a predetermined number of times in a second predetermined period of time, the abnormality sensing unit determines that the state is abnormal.