{
  "$type": "site.standard.document",
  "description": "An air-fuel ratio imbalance among cylinders determining apparatus according to the present invention comprises an air-fuel ratio sensor having a protective cover and an air-fuel ratio detection element accommodated in the protective cover, and imbalance determining means. The imbalance determining…",
  "path": "/patents/1002566",
  "publishedAt": "2012-05-09T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "F02D41/0085",
    "TOYOTA MOTOR CO LTD [JP]"
  ],
  "textContent": "An air-fuel ratio imbalance among cylinders determining apparatus according to the present invention comprises an air-fuel ratio sensor having a protective cover and an air-fuel ratio detection element accommodated in the protective cover, and imbalance determining means. The imbalance determining means obtains a detected air-fuel ratio abyfs based on an output Vabyfs of the air-fuel ratio sensor every elapse of a constant sampling time ts, and obtains, as an indicating amount of air-fuel ratio change rate, a difference (detected air-fuel ratio change rate AF) between a present detected air-fuel ratio abyfs which is newly detected and a previous air-fuel ratio abyfsold which was detected the sampling time ts ago, an average of the detected air-fuel ratio change rate AF, and the like. The imbalance determining means determines that the air-fuel ratio imbalance among cylinders state is occurring, when a magnitude of the indicating amount of air-fuel ratio change rate is larger than an imbalance determination threshold.",
  "title": "DEVICE FOR DECIDING AN IMBALANCE OF AIR/FUEL RATIOS BETWEEN CYLINDERS OF AN INTERNAL COMBUSTION ENGINE"
}