| 摘要 |
PURPOSE:To excellently obtain information on combustion time for control to the best ignition period by providing detecting circuit which outputs a trigger signal when the pressure in a cylinder is maximized, and regarding the period from an ignition period signal to be trigger signal as the combustion time. CONSTITUTION:When combustion pressure is applied to a pressure receiving plate 5, strain is generated and the pressure receiving plate 5 made of a ferromagnetic material varies in magnetic permeability, so magnetic flux phi passing an intermediate shaft 3 varies, inducing a voltage across a coil 2. This voltage is amplified by a differential operational amplifier 21 and inputted to an integrating capacitor 32. When a cylinder pressure signal is inverted, the output of a comparator 31 is inverted, and this point of time is regarded as the peak of the pressure in a cylinder. The rise of an ignition period signal sets a flip-flop 43 and the fall of the output signal of the comparator 31 resets it. Therefore, the output width of the flip-flop 43 corresponds to combustion time and clock pulses are counted and converted into time. |
