{
  "$type": "site.standard.document",
  "description": "It is possible to prevent the stability of an engine from deteriorating even when degrees of changes over time of injection characteristics are different in each fuel injection valve. An inter-cylinder air-fuel ratio variation detection unit 1100 calculates an air-fuel ratio variation index…",
  "path": "/patents/955279",
  "publishedAt": "2015-11-25T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "F02D41/0085",
    "HITACHI AUTOMOTIVE SYSTEMS LTD [JP]"
  ],
  "textContent": "It is possible to prevent the stability of an engine from deteriorating even when degrees of changes over time of injection characteristics are different in each fuel injection valve. An inter-cylinder air-fuel ratio variation detection unit 1100 calculates an air-fuel ratio variation index (Ind_imb) which indicates a degree of variation in an air-fuel ratio between cylinders from an exhaust air-fuel ratio, engine rotation speed, or the like. Unlike in a case where the air-fuel ratio variation index (Ind_imb) is lower than a set value, when the air-fuel ratio variation index (Ind_imb) is higher than the set value, a fuel injection pulse width limitation unit 2100 sets a (allowable) minimum value (Min_TI) of a fuel injection pulse width so as to be greater. In addition, a fuel injection pulse width calculation unit 3100 calculates fuel injection pulse widths (TI_1, TI_2, TI_3, and TI_4) of cylinders so as not to be lower than the minimum value (Min_TI).",
  "title": "CONTROL DEVICE AND CONTROL METHOD OF ENGINE"
}