| 摘要 |
1,229,973. Feeding sheets. R.C.A. CORPORATION. 8 July, 1968 [25 July, 1967], No. 32445/68. Heading B8R. Detecting double-feed.-The passage time of a document past a given point in a feed path is sensed and compared with the passage time of a document of proper length. Sheets 2 are separated from a stack in magazine 1 by friction belt 5, ejected through a throat 8 and conveyed between guides 9, 10, 11 and 12, past a reading station and into hopper 3. The leading and trailing edges of each sheet are detected by a sensing means comprising lamp 14 and photocell 15 and the time of passage of each sheet past point 13 is compared in circuit 16 with the passage time of a sheet of proper length. The passage time of a proper sheet is set up in circuit 16 by movement of guide 20 against the trailing edges of sheets 2 in magazine 1. A sheet of more than proper length indicates a double feed and alarm 21 is sounded. Circuit 16 (Fig. 2, not shown) comprises a threshold detector and when the output signal from cell 15 (integrated with a fixed voltage) exceeds a set value in the detector (as determined by the position of guide 20), the alarm is sounded. |
