| 摘要 |
PURPOSE:To decide whether a sealed can is defective or not by measuring distances between distance detectors and a body to be inspected and calculating the size of the objective body. CONSTITUTION:Distance detection signals corresponding to intervals from the body 1 to be inspected which is passed between the distance detectors 2 and 3 facing each other at a specific distance C are supplied to detection signal selecting circuits 6 and 7 through amplifier circuits 4 and 5. A photoelectric converting element 12 detects relative position relations between the objective body 1 and detectors 2 and 3 and puts a pulse generator 13 in operation when the objective body 1 reaches an optimum position, thereby generating a desired timing pulse. This pulse is inputted to selecting circuits 6 and 7 to segment necessary parts of the detection signals from the detectors 2 and 3 and input the results to A/D converters 8 and 9. Then digital distance detection signals are inputted to an arithmetic circuit 10, which calculates the size value S of the objective body 1 from S=C-(A+B). Then, the size value S is inputted to a quality decision device 11 and compared with a reference signal from a reference signal generating device 14 to decide whether the objective body 1 is normal or not. |
