RESIDUAL ROLL PAPER DETECTION SYSTEM

摘要

PURPOSE:To realize a system having simple structure and no restriction for installing the display portion by providing means for displaying the potential variation due to variation of resistance of resistor variable with correspondence to the rotary variation of tongue chip slidable against the surface of paper roll. CONSTITUTION:The system is adjusted by adjusting a variable resistor 13 such that the reading of ammeter 14 will be zero upon mounting of a yet-used paper roll 1 then adjusting a semi-fixed resistor 15 such that the pointer of ammeter 14 will swing fully when the residual amount of paper roll 1 reaches to the limit. Thereafter, a sliding tongue chip 2 will rotate around a shaft 5 as the paper roll 1 reduces to rotate the variable resistor 13 accordingly thus to vary the resistance. Current corresponding with said variation will flow through the ammeter 14 which will inform the residual amount of paper roll 1. Consequently, the residual amount of paper roll 1 can be detected continuously while the ammeter 14 can be installed at random position without structural restriction resulting in facilitation of design.