| 摘要 |
PURPOSE:To contribute to miniaturization of a sector scanning ultrasonic flaw detector with a simple excitation structure by applying an output signal of a decoder sequentially to a set of two vibrators while an output signal corresponding to the largest dicimal number among outputs of the decoder is applied to one vibrator positioned at the center of vibrators arranged parallel or two vibrators in the center thereof to generate an ultrasonic wave with the excitation of the vibrators. CONSTITUTION:Each time a clock pulse 7 is inputted to a counter 6, the counter 6 advances and pulse outputs are produced sequentially at output terminals D1- D9 of a decoder 8. The pulse output comes in regular order. Therefore, the terminals D1-D9 are connected to the vibrators as follows: D1 to A1 and A17, D2 to A2 and A16, D3 to A3 and A15.... So, first the vibrators A1 and A17 are excited and then A2 and A16, A3 and A15... are done. Finally, the terminal D9 excites the vibrator 9 positioned at the center of those A1-A17. In short, ultrasonic waves are generated simultaneously from the vibrators A1 and A17. Then, they are generated from A2 and A16 and A3 and A15 and finally, from A9. |
