Infrared-light length measurement device used for currency counting machine

The utility model relates to the field of fittings of currency counting machines and particularly relates to an infrared-light length measurement device used for a currency counting machine. In the infrared-light length measurement device used for the currency counting machine, fence glue, sensing chips and pins are directly arranged on a circuit board. Elements of an induction part form an integrated structure. After the elements on the induction part are damaged, the whole induction part can be replaced directly so that a new induction part can work normally. Technical personnel can maintain damaged elements after the induction part which has the damaged elements is disassembled so that the maintenance speed of the induction part is improved and the induction part is simple in structure. Moreover, through arrangement of the fence glue and a silicon sheet, interferences from visible light on the sensing chips can be prevented effectively so that the anti-interference capability of the induction part during w