| 摘要 |
PURPOSE:To exactly detect the small fold of printing paper or a small piece at the end of the printing paper by detecting the presence of printing paper during the period when it passes by a detector provided at the side end of the forward end of a printing paper whose position is set up. CONSTITUTION:A detector 20 is provided in the face of a printing paper 2 at the side end of the passing direction of the paper 2 whose forward and side regular positions are present, a fan-shaped detector 28 turning one time when a swing goes and returns one time is fixed to a rotary shaft 29 turning with the driving mechanism of the swing, and a fan-shaped detector 30 is rotatably provided to the rotary shaft 29 in such a way that it can optionally overlap on the detector 28. And, a timing sensor 32 is provided to the circular peripheral side of the detectors 28 and 30. And, the relative positions between the detectors 28 and 30 and the timing sensor 32 are set up in such a way that during the period when the forward end of the paper 2 passed through the position of the sensor 20 and then its backward end passes there, a detection timing signal is sent forth synchronously. |
