CONTACT POSITION DETECTOR

PURPOSE:To discriminate a plurality of contact points by two output lines, by providing a common resistor on one end of a contact point of many contact detectors, and providing resistors having different value on the other ends thereof. CONSTITUTION:One side of two metal plate of each of the contact detectors 11-13 is connected to one line and grounded through a load resistor RF. Meanwhile the other sides are combined to one line through contact identifying resistors R1-R3 having the different resistance values. A voltage V is applied to this line. When an expression Z(R1-R3) shows impedance comprising the contact identifying resistances R1-R3 and an expression Z(R1)not equal to Z(R2)not equal to ...not equal to Z(R2, R3) not equal to Z(R1-R3) is held, an output Vout can take the different values for the contact states of all the contact detectors. Namely, the number of the contact detectors that are contacted and which contact detectors are contacted can be independently detected.