| 摘要 |
PROBLEM TO BE SOLVED: To provide a number-of-cards detecting device capable of correctly counting the number of magnetic cards in their laminated state even when magnetic cards of which end faces are not uniform or reduced at their light reflection factors are laminated, magnetic cards are laminated in the upside- clown states or the directions or positions of magnetic bands are respectively different. SOLUTION: The one end part of plural magnetic cards having a magnetic recording layer on the whole surface of one face and laminated so that each magnetic recording layer is adjacently laminated to another non-magnetic recording layer is scanned by a magnetic detection part in the laminated direction. A comparator 107 compares the value of a detection signal Sdt with the value of a threshold signal Srf , a counter 108 counts the compared result of the comparator 107 and supplies an AC exciting signal of prescribed frequency to a magnetic detection part, a rectifier circuit 105 rectifies the detection signal Sdt , and a BPF 106 extracts and smooths a prescribed frequency component in an output from the circuit 105 and sets up a value capable of removing a DC component in the output signal of the BPF 106 as the threshold signal Srf . |
