| 摘要 |
<p>PURPOSE:To control air-fuel ratio accurately by cleaning and flowing back an exhaust to inactive cylinder at the time of partial cylinder operation in the manner that a supply of fresh air and fuel is interrupted therefor to a cylinder partly out of operation at the engine being light-loaded. CONSTITUTION:An interrupting valve 18 is opened by output of a control circuit 23 when an engine is medium- or high-loaded, a reflux valve 19 is closed, and a fresh air and fuel are supplied to all cylinders #1-#6. All the cylinders are thus put in operation, and for control of air-fuel ratio in this case, a fuel injection rate is controlled by the control circuit 23 according to output of an oxygen density sensor 21. On the other hand, when the engine operation is shifted to light-loaded condition, the interrupting valve 18 is closed, the reflux valve 19 is opened, a new air supply to the cylinders #4-#6 inactive accordingly is interrupted, exhaust is allowed to flow back to the inactive cylinders through an emission control device 22 and a cooling device 26, and a fuel supply to the inactive cylinders is interrupted at the same time.</p> |
