| 摘要 |
<p>A double detect device (10) includes first and second parallel and superposed rows of steel balls (30) retained in a block (12), the first row (32) being in contact with a steel roller (22) whose axis is parallel to the rows of balls. An actuating rod (40) is urged resiliently against an end ball of the second row (34). In operation, currency notes are fed between the roller (22) and the first row (32) of balls. The passage of a note through the device depresses the balls of the first row (32) thereby urging apart the balls of the second row (34) so as to move the rod (40). If two superposed notes pass through the device movement of the rod is sufficient to actuate a switch (52). The device can distinguish between multiple notes and a single note having a localized increase in thickness, since such single note does not move the rod (40) sufficiently to actuate the switch (52).</p> |
