| 摘要 |
<p>PURPOSE:To correct the scattering of the mass flow rate of burner air due to the atmospheric pressure change and consequently enable to completely burn regardless of the difference of the operating altitude of a diesel engine by a method wherein the amount of lift of an air control valve (ACV) is changed by changing the negative pressure at the venturi in response to the change of the atmospheric pressure. CONSTITUTION:An electrically operated air pump 21 sucks the atmospheric air through an air cleaner 19 and sends the air to ACV24. At this time, because an orifice 27 is annexed to the opening 28 of a communicating passage 25, the faster and larger the air flows, the higher the negative pressure at a venturi becomes, resulting in raising or closing the valve in ACV24 and consequently decreasing the flow rate of the air passing through ACV24. If the operating altitude of a diesel engine becomes higher and consequently the atmospheric pressure becomes lower, the pressure in the atmospheric air chamber of a boost control valve (BCV) 26 lowers and acts to close BCV26, resulting in throttling a passage of the air sucked through the orifice 27 in the venturi 20. Accordingly, the atmospheric air leaks to ACV24 side of a piping 25 so as to make the degree of vacuum of the negative pressure at ACV24, resulting in opening ACV24 and consequently increasing the volumetric flow rate of the air passing through ACV24. In such a manner as mentioned above, the change of mass flow rate of the burner air due to the change of the atmospheric pressure is corrected.</p> |
