| 摘要 |
PURPOSE:To take an automatic diagnosis of an engine speedily and securely at distance without contact, by receiving radio electric or soundwave signals from an engine and measuring periods of the signals. CONSTITUTION:An electric noise generated during engine operation is received by an antenna 1 and its signal is detected and amplified by a detecting and amplifying circuit 2, whose output is shaped into a desired waveform by a waveform shaping circuit 3. The shaped waveform is supplied to a period measuring part 4, where counters A and B measure the period of each signal pulse with a clock signal from a timing controller circuit 10. Each period difference of each signal pulse is then calculated by a period calculating part 5 and compared by each reference value 7 by a comparing and deciding part 6 to decide whether it corresponds to a permissible difference or not. Its output signal is sent to a recording, updating, and displaying part 8 for the decision result to display whether the engine is normal or not by flashing a lamp 9. |
