{
  "$type": "site.standard.document",
  "description": "Provided is an exhaust purification system for an internal combustion engine. The exhaust purification system comprising: a NOpurifying catalyst arranged in an exhaust passage of the internal combustion engine, wherein the NOpurifying catalyst comprises a base metal supported on a catalyst support…",
  "path": "/patents/974684",
  "publishedAt": "2014-05-21T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "F01N11/007",
    "TOYOTA MOTOR CO LTD [JP]"
  ],
  "textContent": "Provided is an exhaust purification system for an internal combustion engine. The exhaust purification system comprising: a NOpurifying catalyst arranged in an exhaust passage of the internal combustion engine, wherein the NOpurifying catalyst comprises a base metal supported on a catalyst support; an oxygen sensor arranged at the downstream side of the NOpurifying catalyst in the exhaust passage; and an air-fuel ratio control means for controlling the air-fuel ratio of exhaust gas flowing into the NOpurifying catalyst; wherein when the NOpurifying catalyst suffers from predetermined oxygen poisoning, the air-fuel ratio control means controls the air-fuel ratio of the exhaust gas, which flows into the NOpurifying catalyst, to a first air-fuel ratio wherein the first air-fuel ratio is richer than a theoretical air-fuel ratio, and then the air-fuel ratio control means switches the air-fuel ratio of the exhaust gas, which flows into the NOpurifying catalyst, to a second air-fuel ratio on the basis of an output value from the oxygen sensor wherein the second air-fuel ratio is leaner than the first air-fuel ratio.",
  "title": "EXHAUST GAS PURIFICATION DEVICE FOR INTERNAL COMBUSTION ENGINE"
}