Copyright © Philip M. Parker, INSEAD. Terms of Use.
| Year | Description |
| 1993 | Invention patented by Masao Yonekawa on May 2nd, 1993. Abstract: A bypass air flow rate control apparatus has an idle speed control valve for continuously adjusting an air flow rate and an on-off control valve for allowing and shutting off an air flow passing therethrough. When an atmospheric pressure sensor detects that the atmospheric pressure is lower than a predetermined value, in other words, the density of intake air is lower than a predetermined value, the on-off control valve and the idle speed control valve are switched over. The air flows through the on-off control valve by an amount corresponding to the air flow rate reduced in the idle speed control valve. The valve switching over operation is performed when one of the following three conditions is satisfied: the engine is generating no torque, in other words, the engine is in a fuel cut operation; a load larger than a predetermined load value is applied; and the engine is accelerated at a rate equal to or greater than a predetermined value. In the latter two conditions, a large torque is generated by the engine. As a result, a torque variation due to the air flow rate variation upon the valve switch over is restrained, so that the vehicle shock which gives a driver a feeling of uneasiness can be relieved and the drivability can be improved. |
| Source: selected by the editor from original sources. | |
Copyright © Philip M. Parker, INSEAD. Terms of Use.
