Patent ID: 9527315
Filing Date: 2016-12-27
CPC Classification: B41J,B65H,G01B

Claim Text:
1. A detector apparatus, comprising: a support unit having a support surface for supporting an outer circumferential surface of a roll; a mechanical switch disposed on the support unit to come in physical contact with the outer circumferential surface of the roll to detect a change in an outer diameter or weight of the roll in response to the physical contact; a photo sensor disposed on a side plate perpendicular to the support surface of the support unit to detect a change in a relative position of an inner circumferential surface of the roll relative to the support surface by detecting whether or not a side face of the roll is present at a spatial position detectable by the photo sensor; and a detector configured to detect a near end of the roll in response to both an output of the mechanical switch and an output of the photo sensor.