| 摘要 |
PURPOSE:To stop feeding of sheet material upon detection of sheet having different thickness by providing means for detecting the thickness of sheet material in the carrying path of sheet material. CONSTITUTION:Upon rotation of double feed detection roller 10 in the direction (c), the sheet material in upper layer is held between a pair of double feed detection rollers 9, 10 and carried further in the direction (b) to move said roller 10 upward by the distance corresponding with the thickness of sheet material. Consequently, Piezo elements 11-13 are pushed with such pressure as corresponding with the motion to produce corresponding voltage which is fed through an amplifier to a microcomputer. An input corresponding with the thickness of single sheet has been stored in the microcomputer to be compared with the input fed from Piezo electric element and if the latter is higher than the stored level, an output is produced to stop the sheet material feed roller 2 through control means and to provide a double feed display. |
