| 摘要 |
PURPOSE:To detect the ignition timing in the Diesel engine more correctly by a method wherein a differential output type pressure sensor is employed to add the correction of a revolving number to the change of pressure and detect the timing when the pressure increases suddenly as the ignition timing. CONSTITUTION:The ignition timing detecting device 3 resets a counter 35 at the leading edge of an upper dead point signal S(241) and begins the counting of a clock signal S(22) at the trailing edge of the same. A piezo-electric element is utilized in the pressure detecting device, outputting the signal S(1) representing the change of pressure per time or dp/dt. By the signal, the output S(34) of a comparating circuit 34 becomes high level and the counting of the counter 35 is stopped by the leading edge of the output S(34). In other words, the content of the counter 35 when the comparating circuit 3 has become high level becomes the ignition timing measured by a crank angle from the upper dead point of the fore cycle. According to this method, the detection of the ignition timing in the Diesel engine may be effected more correctly. |
