| 摘要 |
<p>The monitoring arrangement is used with a spark ignition system (10, 13) in which the spark discharge current oscillates at a known frequency, and includes a sonic sensor (30) accoustically coupled to the spark igniter (13), a detector circuit (33, 35, 37, 38) responsive only to signals from the sensor (30) which have a frequency substantially equal to that of the spark discharge current, and an indicating device (43) responsive to an output signal from the detector circuit (33, 35, 37, 38). </p> |
