| 摘要 |
<p>PURPOSE:To obtain a stable and highly efficient filter regenerating device for internal-combustion engine by providing pressure sensors before and behind a DPF and judging the regenerating time from the ratio between the sizes of the AC components, and from the pressure signals, of the outputs of both sensors. CONSTITUTION:Pressures before and behind a DPF 5 are transduced into electric signals by means of pressure 22, 22', through pressure measuring tubes 21, 21' provided on an exhaust pipe 3. These pressure signals are amplified by amplifiers 23, 23' and are separated into DC components and AC components by means of high-pass filter circuits 24, 24' and low-pass filter circuits 25, 25' respectively. The DC components are operated through a subtraction circuit 27 to produce a difference between the DC components, i.e., a pressure loss, which is outputted to a processing circuit 28. As for the AC components, the ratio between the sizes of the AC signals is operated through a division circuit 26 and the result is outputted to the processing circuit 28. The processing circuit 28 outputs a signal to make a control circuit 7 carry out the regeneration of the DPF based on said two signals.</p> |
